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Sample records for ct initial experience

  1. Initial experience with AcQsim CT simulator

    International Nuclear Information System (INIS)

    Michalski, Jeff M.; Gerber, Russell; Bosch, Walter R.; Harms, William; Matthews, John W.; Purdy, James A.; Perez, Carlos A.

    1995-01-01

    Purpose: We recently replaced our university developed CT simulator prototype with a commercial grade spiral CT simulator (Picker AcQsim) that is networked with three independent virtual simulation workstations and our 3D radiation therapy planning (3D-RTP) system multiple workstations. This presentation will report our initial experience with this CT simulation device and define criteria for optimum clinical use as well as describe some potential drawbacks of the current system. Methods and Materials: Over a 10 month period, 210 patients underwent CT simulation using the AcQsim. An additional 127 patients had a volumetric CT scan done on the device with their CT data and target and normal tissue contours ultimately transferred to our 3D-RTP system. We currently perform the initial patient localization and immobilization in the CT simulation suite by using CT topograms and a fiducial laser marking system. Immobilization devices, required for all patients undergoing CT simulation, are constructed and registered to a device that defines the treatment table coordinates. Orthogonal anterior and lateral CT topograms document patient alignment and the position of a reference coordinate center. The volumetric CT scan with appropriate CT contrast materials administered is obtained while the patient is in the immobilization device. On average, more than 100 CT slices are obtained per study. Contours defining tumor, target, and normal tissues are drawn on a slice by slice basis. Isocenter definition can be automatically defined within the target volume and marked on the patient and immobilization device before leaving the initial CT simulation session. Virtual simulation is then performed on the patient data set with the assistance of predefined target volumes and normal tissue contours displayed on rapidly computed digital reconstructed radiographs (DRRs) in a manner similar to a conventional fluoroscopic radiotherapy simulator. Lastly, a verification simulation is

  2. Cardiac 82rubidium PET/CT: initial European experience

    International Nuclear Information System (INIS)

    Groves, Ashley M.; Dickson, John C.; Kayani, Irfan; Endozo, Raymondo; Blanchard, Patty; Shastry, Manu; Prvulovich, Elizabeth; Waddington, Wendy A.; Ben-Haim, Simona; Bomanji, Jamshed B.; Ell, Peter J.; Speechly-Dick, Marie-Elsya; McEwan, Jean R.

    2007-01-01

    Myocardial perfusion with PET/CT has advantages over conventional SPECT. We describe our initial European experience using 82 Rubidium-PET/CT, as part of a clinical myocardial perfusion service. We studied the first 100 patients (64 male; 36 female, mean age = 60: SD +/-12.5y, mean body mass index = 30: SD +/-6.9kg/m 2 ) who underwent 82 Rubidium cardiac PET/CT in our institution. Thirty patients had recently undergone coronary angiography. Patients underwent imaging during adenosine infusion and at rest. Images were acquired over 5 minutes using a GE-PET/CT instrument. Image quality was described as good, adequate or inadequate. Images were reported patient-by-patient by a minimum of five nuclear medicine physicians. A segment-by-segment analysis (17-segment model) was also performed. Image quality was good in 77%, adequate 23% and inadequate 0%. There was no statistical difference in image quality between obese and non-obese patients (Fisher's exact test, p = 0.2864). 59% had normal perfusion studies, 29% had inducible ischaemia, 12% had myocardial infarction (11% with super added ischaemia). There was reduced 82 Rubidium uptake in 132/1700 segments during stress. There was reduced 82 Rubidium uptake at rest in 42/1700 segments. The 82 Rubidium PET/CT findings were consistent with the angiographic findings in 28/30 cases. We show that, even from initial use of 82 Rubidium, it is possible to perform myocardial perfusion studies quickly with good image quality, even in the obese. The PET findings correlated well in the third of the cases where angiography was available. As such, 82 Rubidium cardiac PET/CT is likely to be an exciting addition to the European nuclear physician/ cardiologist's radionuclide imaging arsenal. (orig.)

  3. CT guided percutaneous needle biopsy of the chest: initial experience

    African Journals Online (AJOL)

    The objective of this article is to report our first experience of CT guided percutaneous thoracic biopsy and to demonstrate the accuracy and safety of this procedure. This was a retrospective study of 28 CT-Guided Percutaneous Needle Biopsies of the Chest performed on 24 patients between November 2014 and April 2015.

  4. Multi-detector CT knee arthrography - initial experience

    International Nuclear Information System (INIS)

    Thomson, J.M.Z.; Fallon, M.; Breidahl, W.H.

    2002-01-01

    Full text: Traditional plain film arthrography can achieve reasonable accuracy and is an accepted method of investigation of patients with knee pain and possible meniscal tear. Multi-detector CT can potentially provide a more detailed and accurate examination due to its high-resolution crosssectional and multi-planar capabilities. The aim of this study was to assess the accuracy of our technique. All patients who underwent a multi-detector CT knee arthrogram in an initial 8 month period were identified. Initially the referring clinician was contacted. If the patient was referred to an orthopaedic surgeon the outcome of orthopaedic review was recorded using clinical, arthroscopic and / or MRI follow-up of the patient population. One hundred and twelve patients had a Multi-detector CT knee arthrogram performed within and 8 month period. Follow-up information was received in 69.7% of patients. Of these 68.9% had orthopaedic assessment - of which 69.2% underwent a knee arthroscopy.There was total agreement of findings in 67%, agreement of meniscal findings in 67% and chondral findings in 100%. Overall, orthopaedic opinion agreed with CT findings in 76.9%. At this stage, all meniscal tears not described in the initial CT arthrogram report have in retrospect been visible. Multi-detector CT knee arthrography is an accurate and elegant technique for investigation of knee pain, providing information in a format familiar to those reporting knee MRI. There is an initial learning curve. The technique is particularly useful in chondral assessment. It is accurate for meniscal pathology, although caution and recognition of potential pitfalls is required. Copyright (2002) Blackwell Science Pty Ltd

  5. CT-guided conformal cryoablation for peripheral NSCLC: Initial experience

    International Nuclear Information System (INIS)

    Zhang, Xiao; Tian, Jinlin; Zhao, Lei; Wu, Bin; Kacher, Daniel S.; Ma, Xuyang; Liu, Shurong; Ren, Chao; Xiao, Yue-Yong

    2012-01-01

    Purpose: To study the feasibility of CT-guided and monitored percutaneous conformal cryoablation of Non-Small Cell Lung Cancer for patients who are not suitable for surgical resection. Materials and method: CT-guided percutaneous conformal cryoablation was performed on 46 patients with peripheral Non-Small Cell Lung Cancer. Patients with tumor sizes less than 3 cm in diameter were treated with double-needle clamping cryoablation, while the patients with 3–5 cm tumor sizes were treated with multiple-needle conformal cryoablation. CT was used to monitor the extent of cryoablation during the procedures. At month 1, 3, 6, 12, and 24 post-procedure, enhanced CT scans and/or PET-CT scans were performed to evaluate the impact of the therapy. Results: The average tumor CT values were 32 ± 10 HU and −21 ± 8 HU before and after cryoablation, respectively. The largest diameters of the lesions at month 1, 3, 6, 12, and 24 post-procedure were 2.63 ± 0.56 cm, 1.93 ± 0.51 cm, 1.55 ± 0.39 cm, 1.43 ± 0.40 cm, and 1.38 ± 0.38 cm, respectively, in patients with tumor diameter less than 3 cm, and 3.63 ± 0.39 cm, 2.98 ± 0.31 cm, 2.62 ± 0.32 cm, 2.54 ± 0.34 cm, and 2.56 ± 0.37 cm respectively in patients with the tumor diameters between 3 and 5 cm. At the 24th month, there were 36 cases of complete response (83.7%), 7 cases of partial response (16.3%), and no cases of stable disease or progressive disease. 3 patients died due to multiple metastases. Conclusion: CT-guided percutaneous conformal cryoablation is a safe, effective, and minimally invasive therapeutic method for peripheral lung cancer.

  6. Initial clinical experience with spiral CT angiography in the abdomen

    International Nuclear Information System (INIS)

    Gaa, J.; Stehling, M.K.; Costello, P.

    1993-01-01

    The latest developments in modern CT instruments, offering scanning times of a second, opened up new possibilities in CT imaging in combination with the spiral technique. The data set normally taken with single-breath-hold technique is free of respiratory artefacts and thus is a good basis for accurate 3D image reconstruction. Spiral CTA allows a non-invasive 3D imaging of various blood vessels. Patients with abdominal aortic aneurysms of aorto-iliac bypass can be examined as outpatients within 15 minutes. (orig.) [de

  7. Myocardial delayed-enhancement CT: initial experience in children and young adults

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul (Korea, Republic of)

    2017-10-15

    Clinical utility of myocardial delayed enhancement CT has not been reported in children and young adults. To describe initial experience of myocardial delayed enhancement CT regarding image quality, radiation dose and identification of myocardial lesions in children and young adults. Between August 2013 and November 2016, 29 consecutive children and young adults (median age 16 months) with suspected coronary artery or myocardial abnormality underwent arterial- and delayed-phase cardiac CT at our institution. We measured CT densities in normal myocardium, left ventricular cavity, and arterial and delayed hypo-enhancing and delayed hyperenhancing myocardial lesions. We then compared the extent of delayed hyperenhancing lesions with delayed-enhancement MRI or thallium single-photon emission CT. Normal myocardium and left ventricular cavity showed significantly higher CT numbers on arterial-phase CT than on delayed-phase CT (t-test, P<0.0001). Contrast-to-noise ratios of the arterial and delayed hypo-enhancing and delayed hyperenhancing lesions on CT were 26.7, 17.6 and 18.7, respectively. Delayed-phase CT findings were equivalent to those of delayed-enhancement MRI in all cases (7/7) and to those of thallium single-photon emission CT in 70% (7/10). Myocardial delayed-enhancement CT can be added to evaluate myocardial lesions in select children and young adults with suspected coronary artery or myocardial abnormality. (orig.)

  8. Myocardial delayed-enhancement CT: initial experience in children and young adults

    International Nuclear Information System (INIS)

    Goo, Hyun Woo

    2017-01-01

    Clinical utility of myocardial delayed enhancement CT has not been reported in children and young adults. To describe initial experience of myocardial delayed enhancement CT regarding image quality, radiation dose and identification of myocardial lesions in children and young adults. Between August 2013 and November 2016, 29 consecutive children and young adults (median age 16 months) with suspected coronary artery or myocardial abnormality underwent arterial- and delayed-phase cardiac CT at our institution. We measured CT densities in normal myocardium, left ventricular cavity, and arterial and delayed hypo-enhancing and delayed hyperenhancing myocardial lesions. We then compared the extent of delayed hyperenhancing lesions with delayed-enhancement MRI or thallium single-photon emission CT. Normal myocardium and left ventricular cavity showed significantly higher CT numbers on arterial-phase CT than on delayed-phase CT (t-test, P<0.0001). Contrast-to-noise ratios of the arterial and delayed hypo-enhancing and delayed hyperenhancing lesions on CT were 26.7, 17.6 and 18.7, respectively. Delayed-phase CT findings were equivalent to those of delayed-enhancement MRI in all cases (7/7) and to those of thallium single-photon emission CT in 70% (7/10). Myocardial delayed-enhancement CT can be added to evaluate myocardial lesions in select children and young adults with suspected coronary artery or myocardial abnormality. (orig.)

  9. Dual-source CT cardiac imaging: initial experience

    International Nuclear Information System (INIS)

    Johnson, Thorsten R.C.; Nikolaou, Konstantin; Wintersperger, Bernd J.; Rist, Carsten; Buhmann, Sonja; Reiser, Maximilian F.; Becker, Christoph R.; Leber, Alexander W.; Ziegler, Franz von; Knez, Andreas

    2006-01-01

    The relation of heart rate and image quality in the depiction of coronary arteries, heart valves and myocardium was assessed on a dual-source computed tomography system (DSCT). Coronary CT angiography was performed on a DSCT (Somatom Definition, Siemens) with high concentration contrast media (Iopromide, Ultravist 370, Schering) in 24 patients with heart rates between 44 and 92 beats per minute. Images were reconstructed over the whole cardiac cycle in 10% steps. Two readers independently assessed the image quality with regard to the diagnostic evaluation of right and left coronary artery, heart valves and left ventricular myocardium for the assessment of vessel wall changes, coronary stenoses, valve morphology and function and ventricular function on a three point grading scale. The image quality ratings at the optimal reconstruction interval were 1.24±0.42 for the right and 1.09±0.27 for the left coronary artery. A reconstruction of diagnostic systolic and diastolic images is possible for a wide range of heart rates, allowing also a functional evaluation of valves and myocardium. Dual-source CT offers very robust diagnostic image quality in a wide range of heart rates. The high temporal resolution now also makes a functional evaluation of the heart valves and myocardium possible. (orig.)

  10. Initial experience with FDG-PET/CT in the evaluation of breast cancer

    International Nuclear Information System (INIS)

    Tatsumi, Mitsuaki; Cohade, Christian; Mourtzikos, Karen A.; Wahl, Richard L.; Fishman, Elliot K.

    2006-01-01

    We retrospectively reviewed FDG-PET/CT images in patients with breast cancer to determine whether PET/CT improved the level of diagnostic confidence as compared with PET and to compare PET/CT and CT findings at the location of suspected malignancies. The study included 75 patients with known breast cancer. The initial PET/CT study for each patient was retrospectively reviewed to determine whether improved diagnostic confidence (IDC) regarding lesion localization and characterization was observed with PET/CT as compared with PET alone. PET/CT and CT findings were compared regarding lesion characterization and staging in 69 of the 75 patients, and in the case of discordant findings, comparison with histological or informative follow-up results was also performed. Fifty of the 75 patients exhibited increased FDG uptake in a total of 95 regions. In the comparison of PET/CT and PET, PET/CT resulted in IDC in 30 (60%) of these 50 patients and in 52 (55%) of the 95 regions. In the comparison between PET/CT and CT in 69 patients, PET/CT demonstrated a significantly better accuracy than CT (P<0.05). PET/CT showed definitely positive findings in 60 regions with malignancies, among which CT exhibited positive findings in 43 (72%). PET/CT and CT accurately staged 59 (86%) and 53 (77%) of the 69 patients, respectively. (orig.)

  11. CT-guided spinal injection: initial experience with Sprotte tip needles

    Energy Technology Data Exchange (ETDEWEB)

    Pua, Uei [Tan Tock Seng Hospital, Department of Diagnostic Radiology, Singapore (Singapore)

    2010-09-15

    The purpose of this paper is to describe our initial experience and to illustrate the potential benefits of using small caliber (25 and 27 G), noncutting pencil point needles (Sprotte) with single puncture coaxial technique in CT-guided spinal intervention (CTSI). From January 2009 to June 2009, Sprotte needles with single puncture coaxial technique were used in a total of ten patients for selective nerve root block (SNRB), facet joint block, and pars block under CT fluoroscopy (total of 16 target structures). All procedures were performed without conscious sedation, and visual analog scale (VAS) scores were recorded to determine pain related to needle placement. Total CT fluoroscopy time and out-of-plane needle deviation were obtained. Final needle position was documented by contrast injection for SNRBs and image capture for joint space cannulation. Sixteen out of the 16 structures were successfully targeted. No increase in VAS scores associated with needle placement was recorded, after infiltration of local anesthesia. Optimal peri-neurograms were obtained in all cases of SNRB, despite the side-hole opening in the Sprotte needles. Mean CT fluoroscopy time was 2 s (range 2-8 s per structure), and there was no case of out-of-plane needle deviation that required adjustment of the CT gantry. The use of small caliber Sprotte needles in CTSI is technically feasible and represents a potential refinement to current techniques in the management of chronic spinal pain. (orig.)

  12. Enhanced temporal resolution at cardiac CT with a novel CT image reconstruction algorithm: Initial patient experience

    Energy Technology Data Exchange (ETDEWEB)

    Apfaltrer, Paul, E-mail: paul.apfaltrer@medma.uni-heidelberg.de [Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, PO Box 250322, 169 Ashley Avenue, Charleston, SC 29425 (United States); Institute of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim (Germany); Schoendube, Harald, E-mail: harald.schoendube@siemens.com [Siemens Healthcare, CT Division, Forchheim Siemens, Siemensstr. 1, 91301 Forchheim (Germany); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, PO Box 250322, 169 Ashley Avenue, Charleston, SC 29425 (United States); Allmendinger, Thomas, E-mail: thomas.allmendinger@siemens.com [Siemens Healthcare, CT Division, Forchheim Siemens, Siemensstr. 1, 91301 Forchheim (Germany); Tricarico, Francesco, E-mail: francescotricarico82@gmail.com [Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, PO Box 250322, 169 Ashley Avenue, Charleston, SC 29425 (United States); Department of Bioimaging and Radiological Sciences, Catholic University of the Sacred Heart, “A. Gemelli” Hospital, Largo A. Gemelli 8, Rome (Italy); Schindler, Andreas, E-mail: andreas.schindler@campus.lmu.de [Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, PO Box 250322, 169 Ashley Avenue, Charleston, SC 29425 (United States); Vogt, Sebastian, E-mail: sebastian.vogt@siemens.com [Siemens Healthcare, CT Division, Forchheim Siemens, Siemensstr. 1, 91301 Forchheim (Germany); Sunnegårdh, Johan, E-mail: johan.sunnegardh@siemens.com [Siemens Healthcare, CT Division, Forchheim Siemens, Siemensstr. 1, 91301 Forchheim (Germany); and others

    2013-02-15

    Objective: To evaluate the effect of a temporal resolution improvement method (TRIM) for cardiac CT on diagnostic image quality for coronary artery assessment. Materials and methods: The TRIM-algorithm employs an iterative approach to reconstruct images from less than 180° of projections and uses a histogram constraint to prevent the occurrence of limited-angle artifacts. This algorithm was applied in 11 obese patients (7 men, 67.2 ± 9.8 years) who had undergone second generation dual-source cardiac CT with 120 kV, 175–426 mAs, and 500 ms gantry rotation. All data were reconstructed with a temporal resolution of 250 ms using traditional filtered-back projection (FBP) and of 200 ms using the TRIM-algorithm. Contrast attenuation and contrast-to-noise-ratio (CNR) were measured in the ascending aorta. The presence and severity of coronary motion artifacts was rated on a 4-point Likert scale. Results: All scans were considered of diagnostic quality. Mean BMI was 36 ± 3.6 kg/m{sup 2}. Average heart rate was 60 ± 9 bpm. Mean effective dose was 13.5 ± 4.6 mSv. When comparing FBP- and TRIM reconstructed series, the attenuation within the ascending aorta (392 ± 70.7 vs. 396.8 ± 70.1 HU, p > 0.05) and CNR (13.2 ± 3.2 vs. 11.7 ± 3.1, p > 0.05) were not significantly different. A total of 110 coronary segments were evaluated. All studies were deemed diagnostic; however, there was a significant (p < 0.05) difference in the severity score distribution of coronary motion artifacts between FBP (median = 2.5) and TRIM (median = 2.0) reconstructions. Conclusion: The algorithm evaluated here delivers diagnostic imaging quality of the coronary arteries despite 500 ms gantry rotation. Possible applications include improvement of cardiac imaging on slower gantry rotation systems or mitigation of the trade-off between temporal resolution and CNR in obese patients.

  13. Initial experience of Fag-PET/CT guided Imr of head-and-neck carcinoma

    International Nuclear Information System (INIS)

    Wang Dian; Schultz, Christopher J.; Jursinic, Paul A.; Bialkowski, Mirek; Zhu, X. Ronald; Brown, W. Douglas; Rand, Scott D.; Michel, Michelle A.; Campbell, Bruce H.; Wong, Stuart; Li, X. Allen; Wilson, J. Frank

    2006-01-01

    Purpose: The purpose of this study is to evaluate the impact of 18 F-fluorodeoxyglucose positron emission tomography (Fag-PET) fused with planning computed tomography (CT) on tumor localization, which guided intensity-modulated radiotherapy (Imr) of patients with head-and-neck carcinoma. Methods and Materials: From October 2002 through April 2005, we performed Fag-PET/CT guided Imr for 28 patients with head-and-neck carcinoma. Patients were immobilized with face masks that were attached with five fiducial markers. Fag-PET and planning CT scans were performed on the same flattop table in one session and were then fused. Target volumes and critical organs were contoured, and Imr plans were generated based on the fused images. Results: All 28 patients had abnormal increased uptake in Fag-PET/CT scans. PET/CT resulted in CT-based staging changes in 16 of 28 (57%) patients. PET/CT fusions were successfully performed and were found to be accurate with the use of the two commercial planning systems. Volume analysis revealed that the PET/CT-based gross target volumes (GTVs) were significantly different from those contoured from the CT scans alone in 14 of 16 patients. In addition, 16 of 28 patients who were followed for more than 6 months did not have any evidence of locoregional recurrence in the median time of 17 months. Conclusion: Fused images were found to be useful to delineate GTV required in IMRT planning. PET/CT should be considered for both initial staging and treatment planning in patients with head-and-neck carcinoma

  14. Low-dose CT colonography in children: initial experience, technical feasibility and utility

    International Nuclear Information System (INIS)

    Anupindi, Sudha; Perumpillichira, James; Zalis, Michael E.; Jaramillo, Diego; Israel, Esther J.

    2005-01-01

    CT colonography (CTC) is utilized as a diagnostic tool in the detection of colon polyps and early colorectal cancer in adults. Large studies in the literature, although focused on adult populations, have shown CTC to be a safe, accurate, non-invasive technique. We evaluated the technical feasibility of CTC in children using a low-dose technique. From November 2001 to April 2004 we evaluated eight patients (3-17 years) with non-contrast CTC. Seven of the patients had CTC, followed by standard colonoscopy (SC) the same day; in one patient, CTC followed a failed SC. CTC results were compared to results of SC. The estimated effective dose from each CTC was calculated and compared to that of standard barium enema. CTC results were consistent with those of SC. Sensitivity for polyps 5-10 mm was 100%, and sensitivity for polyps 10 mm and larger was 66.7%. The estimated mean effective dose was 2.17 mSv for CTC, compared to the 5-6 mSv for a standard air-contrast barium enema in a small child. Our initial experience shows CTC in children is well-tolerated, safe, and useful. The procedure can be performed successfully with a low radiation dose, and preliminary results compare well with SC. (orig.)

  15. Evaluation of bone metastases with 18 F- Sodium fluoride PET/CT; initial experience

    International Nuclear Information System (INIS)

    Sanchez C, N.; Serna M, J.A.; Quiroz C, O.; Quinzanos, F.; Valenzuela, J.; Ramirez A, J.L.

    2007-01-01

    The study of NaF-18 PET/CT is the modality with bigger sensitivity and specificity for the bony metastases detection. This additional value of the NaF-18 PET/CT can have a beneficent impact in the clinical handling of the patients with prostate cancer with high risk. (Author)

  16. PET/MRI and PET/CT in advanced gynaecological tumours: initial experience and comparison

    Energy Technology Data Exchange (ETDEWEB)

    Queiroz, Marcelo A.; Schulthess, Gustav von; Veit-Haibach, Patrick [University Hospital Zurich, Department Medical Radiology, Nuclear Medicine, Zurich (Switzerland); University Hospital Zurich, Department Medical Radiology, Diagnostic and Interventional Radiology, Zurich (Switzerland); University of Zurich, Zurich (Switzerland); Kubik-Huch, Rahel A.; Freiwald-Chilla, Bianka [Kantonsspital Baden AG, Department of Radiology, Baden (Switzerland); Hauser, Nik [Kantonsspital Baden AG, Department of Gynaecology, Baden (Switzerland); Froehlich, Johannes M. [Guerbet AG, Zurich (Switzerland)

    2015-08-15

    To compare the diagnostic accuracy of PET/MRI and PET/CT for staging and re-staging advanced gynaecological cancer patients as well as identify the potential benefits of each method in such a population. Twenty-six patients with suspicious or proven advanced gynaecological cancer (12 ovarian, seven cervical, one vulvar and four endometrial tumours, one uterine metastasis, and one primary peritoneal cancer) underwent whole-body imaging with a sequential trimodality PET/CT/MR system. Images were analysed regarding primary tumour detection and delineation, loco-regional lymph node staging, and abdominal/extra-abdominal distant metastasis detection (last only by PET/CT). Eighteen (69.2 %) patients underwent PET/MRI for primary staging and eight patients (30.8 %) for re-staging their gynaecological malignancies. For primary tumour delineation, PET/MRI accuracy was statistically superior to PET/CT (p < 0.001). Among the different types of cancer, PET/MRI presented better tumour delineation mainly for cervical (6/7) and endometrial (2/3) cancers. PET/MRI for local evaluation as well as PET/CT for extra-abdominal metastases had therapeutic consequences in three and one patients, respectively. PET/CT detected 12 extra-abdominal distant metastases in 26 patients. PET/MRI is superior to PET/CT for primary tumour delineation. No differences were found in detection of regional lymph node involvement and abdominal metastases detection. (orig.)

  17. Role of carbon-11 choline PET/CT in the management of uterine carcinoma. Initial experience

    International Nuclear Information System (INIS)

    Sofue, Keitaro; Sawada, Morio; Arai, Yasuaki; Tateishi, Ukihide; Inoue, Tomio; Maeda, Tetsuo; Sugimura, Kazuro; Terauchi, Takashi; Kano, Daisuke

    2009-01-01

    The present study was conducted to clarify the role of carbon-11 choline ( 11 C-choline) positron emission tomography (PET)/computed tomography (CT) in the management of uterine carcinoma. Twenty-two patients who underwent 11 C-choline PET/CT and pelvic MRI were evaluated retrospectively. The images were reviewed by a board-certified radiologist and a nuclear medicine specialist who were unaware of any clinical information, and a consensus was reached. Diagnostic accuracy of PET/CT was evaluated for staging. The reference standard consisted of histological examination (n=17) and follow-up conventional CT (n=5). In five patients with cervical carcinoma, 11 C-choline PET/CT was performed before and after treatment that consisted of cisplatin infusion and subsequent radiotherapy. Standardized uptake value (SUV) was compared with unidimensional and volumetric measurements that were made on magnetic resonance images (MRI) before and after treatment. Based on PET/CT interpretations, the reviewers correctly classified tumor (T) stage in 8 patients (47%), nodes (N) stage in 21 patients (96%), metastasis (M) stage in 20 patients (91%), and tumor, nodes and metastasis (TNM) stage in 15 patients (88%). Tumor size, volume, and SUV decreased after treatment in five patients with cervical carcinoma. Using the Pearson correlation test, a significant correlation was found between the reduction rate of SUV and reduction rate of tumor volume. 11 C-choline PET/CT is an accurate means for the management of patients with uterine carcinoma. The combination of 11 C-choline PET/CT and MRI increases the accuracy of staging in patients with uterine carcinoma. (author)

  18. Four-Dimensional CT of the Diaphragm in Children: Initial Experience

    Science.gov (United States)

    2018-01-01

    Objective To evaluate the technical feasibility of four-dimensional (4D) CT for the functional evaluation of the pediatric diaphragm. Materials and Methods In 22 consecutive children (median age 3.5 months, age range 3 days–3 years), 4D CT was performed to assess diaphragm motion. Diaphragm abnormalities were qualitatively evaluated and diaphragm motion was quantitatively measured on 4D CT. Lung density changes between peak inspiration and expiration were measured in the basal lung parenchyma. The diaphragm motions and lung density changes measured on 4D CT were compared between various diaphragm conditions. In 11 of the 22 children, chest sonography was available for comparison. Results Four-dimensional CT demonstrated normal diaphragm (n = 8), paralysis (n = 10), eventration (n = 3), and diffusely decreased motion (n = 1). Chest sonography demonstrated normal diaphragm (n = 2), paralysis (n = 6), eventration (n = 2), and right pleural effusion (n = 1). The sonographic findings were concordant with the 4D CT findings in 90.9% (10/11) of the patients. In diaphragm paralysis, the affected diaphragm motion was significantly decreased compared with the contralateral normal diaphragm motion (−1.1 ± 2.2 mm vs. 7.6 ± 3.8 mm, p = 0.005). The normal diaphragms showed significantly greater motion than the paralyzed diaphragms (4.5 ± 2.1 mm vs. −1.1 ± 2.2 mm, p Hounsfield units [HU] vs. 180 ± 71 HU, p = 0.03), while no significant differences were found between the normal diaphragms and the paralyzed diaphragms (136 ± 66 HU vs. 89 ± 73 HU, p = 0.1) or between the normal diaphragms and the contralateral normal diaphragms in paralysis (136 ± 66 HU vs. 180 ± 71 HU, p = 0.1). Conclusion The functional evaluation of the pediatric diaphragm is feasible with 4D CT in select children. PMID:29354007

  19. Coronary artery imaging with 64-slice spiral CT in atrial fibrillation patients: initial experience

    International Nuclear Information System (INIS)

    Zhou Xuhui; Yan Chaogui; Xie Hongbo; Li Xiangmin; Li Ziping; Meng Quanfei; Chen Xing

    2008-01-01

    Objective: To discuss the clinical value of coronary artery imaging using 64-slice spiral CT in patient with atrial fibrillation. Methods: The images of 31 patients with atrial fibrillation who underwent contrast-enhanced CT coronary angiography were evaluated. The presence of stenosis on each segment of coronary arteries was recorded and their degree of stenosis was measured using the vessel analysis software. Ten patients additionally underwent conventional coronary angiography. The results of conventional coronary angiography were compared with CT coronary angiography of the 10 patients. Results: Image reconstruction was based on absolute timing. The image quality of 364 coronary vessel segments on the images from 31 patients was evaluated and defined as excellent, fine, moderate or poor. The image quality was excellent, fine, moderate and poor in 85, 41, 5, and 8 vessel segments respectively in patient group with heart rate between 47 beat per minent (bpm) and 69 bpm; and in 63, 16, 13, and 15 vessel segments respectively in patent group with heart rate between 70 bpm and 79 bpm;and in 46, 25, 23, and 24 vessel segments in patient group with heart rate between 80 bpm and 105 bpm. There was significant difference among the three patient groups (H=22.08, P<0.01). Comparison was carried out between CT angiographic findings and conventional angiographic findings of the 125 segments of the coronary arteries in the 10 patients who underwent conventional coronary angiography. The sensitivity and specificity of CT angiography for diagnosing vessel with significant coronary stenosis (≥50% narrowing) was 85.0% (17/20) and 95.2% (100/105), respectively. Positive predictive value was 77.3% (17/22), and negative predictive value was 97.1% (100/103). Coronary CTA underestimated the lesions of 3 vessel segments and overestimated the lesions of 5 vessel segments. Conclusion: Coronary artery imaging with 64-slice row CT had clinical value for patients with atrial fibrillation

  20. Percutaneous Cryoablation of Small Hepatocellular Carcinoma with US Guidance and CT Monitoring: Initial Experience

    International Nuclear Information System (INIS)

    Orlacchio, Antonio; Bazzocchi, Gabriele; Pastorelli, Daniela; Bolacchi, Francesca; Angelico, Mario; Almerighi, Cristiana; Masala, Salvatore; Simonetti, Giovanni

    2008-01-01

    The purpose of this study was to retrospectively determine the safety and effectiveness of percutaneous cryoablation, monitored with computed tomography (CT) and ultrasonographic (US) guidance, for the treatment of hepatocellular carcinoma (HCC). Four patients with small HCCs underwent one percutaneous cryoablation treatment session monitored with CT and US guidance. All patients underwent pretreatment blood chemistry testing and imaging evaluation. We treated lesions with simultaneous insertion of multiple 17-G cryoprobes (two or three) and defined technical success when the extension of a visible iceball was beyond 5 mm from the tumor margin. Intralesional enhancement or tumoral size increase was defined as local progression compared with that on images obtained immediately after ablation. We evaluated complications and follow-up (at 1, 3, and 6 months). All patients survived without short- or long-term complications. Cryoablation was technically successful in all patients at the end of the procedure. During follow-up two patients developed disease recurrence. One patient developed local tumor progression on the margin of the lesion; the other, a new HCC. In the case of local tumor progression a new elevation of α-fetoprotein (αFP) levels occurred at first follow-up control. In the other case levels of αFP remained stable during the first 3 months after the procedure, then demonstrated a progressive increase in αFP levels beginning at the fourth month, without tumor evidence during CT control at 3 months. We conclude that percutaneous cryotherapy with US guidance and CT monitoring is a feasible, safe, and effective for treatment of HCC. If local ablative procedures of hepatic lesions are to be performed, percutaneous cryoablation, not laparotomic, should be discussed as an alternative therapeutic measure. Longer follow-up should provide proof of the effectiveness of this technique

  1. [Virtual bronchoscopy in the child using multi-slice CT: initial clinical experiences].

    Science.gov (United States)

    Kirchner, J; Laufer, U; Jendreck, M; Kickuth, R; Schilling, E M; Liermann, D

    2000-01-01

    Virtual bronchoscopy of the pediatric patient has been reported to be more difficult because of artifacts due to breathing or motion. We demonstrate the benefit of the accelerated examination based on multislice spiral CT (MSCT) in the pediatric patient which has not been reported so far. MSCT (tube voltage 120 kV, tube current 110 mA, 4 x 1 mm Slice thickness, 500 ms rotation time, Pitch 6) was performed on a CT scanner of the latest generation (Volume Zoom, Siemens Corp. Forchheim, Germany). In totally we examined 11 patients (median age 48 months, range 2-122 months) suspected of having tracheoesophageal fistula (n = 2), tracheobronchial narrowing (n = 8) due to intrinsic or extrinsic factors or injury of the bronchial system (n = 1). In all patients we obtained sufficient data for 3D reconstruction avoiding general anesthesia. 6/11 examinations were described to be without pathological finding. A definite diagnosis was obtained in 10 patients. Virtual bronchoscopy could avoid other invasive diagnostic examination in 8/11 patients (73%). Helical CT provides 3D-reconstruction and virtual bronchoscopy in the newborn as well as the infant. It avoids additional diagnostic bronchoscopy in a high percentage of all cases.

  2. Initial experience with megavoltage (MV) CT guidance for daily prostate alignments

    International Nuclear Information System (INIS)

    Langen, Katja M.; Zhang Yashan; Andrews, Rhonda D.; Hurley, Monica E.; Meeks, Sanford L.; Poole, Darrell O.; Willoughby, Twyla R.; Kupelian, Patrick A.

    2005-01-01

    Purpose: The on-board megavoltage (MV) computed tomography (CT) capabilities of a TomoTherapy Hi*ART unit were used to obtain daily MVCT images of prostate cancer patients. For patient alignment the daily MVCT image needs to be registered with the planning CT image to calculate couch shifts. Three manual techniques of registering the MVCT images with the planning kilovoltage (kV) CT images were evaluated. The techniques are based on visual alignment of (1) fiducial prostate markers (2) CT anatomy, and (3) kVCT contours. Methods and Materials: One hundred and twelve alignments from 3 patients were available for analysis. The radiation therapists visually registered the MVCT images with the planning kVCT images based on fiducial markers for actual patient alignment. Retrospectively, the therapists registered each image set using anatomy and contour-based techniques. In addition to the therapists, a physician retrospectively registered each image set based on each of the three techniques. For each MVCT to kVCT image pair a reference alignment was computed from the center-of-mass (COM) of the three fiducial markers. All registration results were compared with these reference alignments. The physician's image registrations were compared with the radiation therapists' registrations to assess the user variability of the different techniques. Results: The marker-based registration results agree best with the reference alignments, while the contour-based registrations show the least degree of agreement. Using anatomy and contour-based registrations, the radiation therapist's alignments differed by ≥ 3 mm from the reference alignments in 24%, 33%, and 3% and 55%, 48%, and 21% of all registrations in the anterior-posterior, superior-inferior, and lateral directions, respectively. The respective values for the marker-based alignments were 3%, 6%, and 3%. The physician's registrations showed the same general trend. The marker-based registrations showed the least amount of

  3. Krypton ventilation imaging using dual-energy CT in chronic obstructive pulmonary disease patients: initial experience.

    Science.gov (United States)

    Hachulla, Anne-Lise; Pontana, François; Wemeau-Stervinou, Lidwine; Khung, Suonita; Faivre, Jean-Baptiste; Wallaert, Benoit; Cazaubon, Jean-François; Duhamel, Alain; Perez, Thierry; Devos, Patrick; Remy, Jacques; Remy-Jardin, Martine

    2012-04-01

    To evaluate the tolerance and level of enhancement achievable after inhalation of stable krypton. This study was approved by the institutional review board and the local ethics committee. Written informed consent was obtained from all subjects. The study was planned as a Fleming two-stage design, enabling one to assess the effectiveness of a newer treatment or technique on a small number of patients. At the end of each stage, the results are computed, and the trial can be stopped if the effectiveness is less than a minimum success rate or greater than an expected success rate. After informed consent was obtained, a total of 32 patients (ie, two successive series of 16 patients each) with severe emphysema underwent a dual-source, dual-energy chest computed tomographic (CT) examination after inhalation of a mixture of stable krypton (80%) and oxygen (20%), with reconstruction of diagnostic and ventilation images. For each patient, two regions of interest were selected on a diagnostic image, one in a region of severe emphysema (presumed to be poorly ventilated or not ventilated) and a second one in a region devoid of structural abnormalities (presumed to be normally ventilated), with measurements of attenuation values on the corresponding ventilation image. All examinations were successfully performed, without adverse effects. Differences in attenuation between normal lung and emphysematous areas were found in 28 patients (88%; 95% confidence interval: 71%, 96.5%). The maximal level of attenuation within normal lung was 18.5 HU. Krypton attenuation difference between normal and emphysematous lung was significant, with a median value of 51.8% (P krypton and its excellent clinical tolerance makes this gas eligible for ventilation CT examinations. © RSNA, 2012.

  4. Fluoroscopic and CT enteroclysis in children: initial experience, technical feasibility, and utility

    International Nuclear Information System (INIS)

    Brown, Shanaree; Applegate, Kimberly E.; Sandrasegaran, Kumar; Jennings, S.G.; Garrett, Joshua; Maglinte, Dean T.; Skantharajah, Arunan

    2008-01-01

    Partial small-bowel obstruction can be difficult to diagnose on clinical examination. These obstructions might not be detected on routine abdominal/pelvic CT. To evaluate the feasibility, safety, and techniques of fluoroscopic enteroclysis (FE) and CT enteroclysis (CTE), and to review their indications and findings in children. We retrospectively reviewed all enteroclysis studies in children younger than 18 years performed between January 2002 and March 2007. We correlated the results with other abdominal imaging and surgical and pathological findings. The review revealed 112 FE and 74 CTE studies performed in 175 children (mean age 14 years, range 3-18 years). FE and CTE studies were performed most commonly for evaluation of known Crohn disease (FE 38%, CTE 29%) and abdominal pain (FE 26%, CTE 26%). One FE study was terminated because of patient anxiety, and one CTE study was terminated because of patient discomfort. No complications of FE or CTE were reported. The findings were normal in 54% of the FE studies and 46% of the CTE studies. The most common small bowel diagnoses were Crohn disease (FE 34%, CTE 28%) and partial small bowel obstruction (FE 3%, CTE 10%). Two FE studies (2%) and 14 CTE studies (19%) showed abnormalities outside the small bowel. In 54 patients with inflammatory bowel disease, 11 FE studies and 25 CTE studies showed additional bowel abnormalities. Overall, 14 and 21 patients had surgery as a result of the findings of FE and CTE, respectively. FE and CTE are safe, feasible, and accurate in depicting small-bowel pathology in children. These techniques can be particularly useful in children with Crohn disease involving the small bowel. (orig.)

  5. Dual energy virtual CT colonoscopy with dual source computed tomography. Initial experience

    International Nuclear Information System (INIS)

    Karcaaltincaba, M.; Karaosmanoglu, D.; Akata, D.; Sentuerk, S.; Oezmen, M.; Alibek, S.

    2009-01-01

    Purpose: To describe the technique of DE MDCT colonoscopy and to assess its feasibility. Materials and Methods: 8 patients were scanned with DSCT with a DE scan protocol and dose modulation software. Analysis was performed using dedicated DE software. Prone non-contrast images and DE supine images after contrast injection were obtained. Results: DE colonoscopic images were successfully obtained in 7 patients, but the FOV did not cover all colonic segments in 1 patient, thus resulting in a technical success rate was 87.5%. Streak artifacts were present in the pelvic region in 2 patients. Virtual unenhanced images and iodine map images were obtained for all patients. In 1 patient a polypoid non-enhancing structure was noted on the iodine map, and conventional colonoscopy revealed impacted stool. Enhancing rectal cancer in 1 patient was correctly shown on the iodine map. Iodine maps helped to differentiate stool fragments/retained fluid by the absence of enhancement when compared to prone CT images. The major advantage of DE colonoscopy was the lack of misregistration. Conclusion: DE MDCT colonoscopy is technically feasible and may obviate the need for unenhanced prone images. It may be possible to perform noncathartic DECT colonoscopy. The major limitation is the limited FOV of tube B. The dose should be optimized to reduce streak artifacts in the pelvic region. (orig.)

  6. Computer-aided detection in CT colonography: initial clinical experience using a prototype system

    International Nuclear Information System (INIS)

    Graser, A.; Geisbuesch, S.; Reiser, M.F.; Becker, C.R.; Kolligs, F.T.; Schaefer, C.; Mang, T.

    2007-01-01

    Computer-aided detection (CAD) algorithms help to detect colonic polyps at CT colonography (CTC). The purpose of this study was to evaluate the accuracy of CAD versus an expert reader in CTC. One hundred forty individuals (67 men, 73 women; mean age, 59 years) underwent screening 64-MDCT colonography after full cathartic bowel cleansing without fecal tagging. One expert reader interpreted supine and prone scans using a 3D workstation with integrated CAD used as ''second reader.'' The system's sensitivity for the detection of polyps, the number of false-positive findings, and its running time were evaluated. Polyps were classified as small (≤5 mm), medium (6-9 mm), and large (≥10 mm). A total of 118 polyps (small, 85; medium, 19; large, 14) were found in 56 patients. CAD detected 72 polyps (61%) with an average of 2.2 false-positives. Sensitivity was 51% (43/85) for small, 90% (17/19) for medium, and 86% (12/14) for large polyps. For all polyps, per-patient sensitivity was 89% (50/56) for the radiologist and 73% (41/56) for CAD. For large and medium polyps, per-patient sensitivity was 100% for the radiologist, and 96% for CAD. In conclusion, CAD shows high sensitivity in the detection of clinically significant polyps with acceptable false-positive rates. (orig.)

  7. Double prospectively ECG-triggered high-pitch spiral acquisition for CT coronary angiography: Initial experience

    International Nuclear Information System (INIS)

    Wang, Q.; Qin, J.; He, B.; Zhou, Y.; Yang, J.-J.; Hou, X.-L.; Yang, X.-B.; Chen, J.-H.; Chen, Y.-D.

    2013-01-01

    Aim: To evaluate the feasibility of double prospectively electrocardiogram (ECG)-triggered high-pitch spiral acquisition mode (double high-pitch mode) for coronary computed tomography angiography (CTCA). Materials and methods: One hundred and forty-nine consecutive patients [40 women, 109 men; mean age 58.2 ± 9.2 years; sinus rhythm ≤70 beats/min (bpm) after pre-medication, body weight ≤100 kg] were enrolled for CTCA examinations using a dual-source CT system with 2 × 128 × 0.6 mm collimation, 0.28 s rotation time, and a pitch of 3.4. Double high-pitch mode was prospectively triggered first at 60% and later at 30% of the R–R interval within two cardiac cycles. Image quality was evaluated using a four-point scale (1 = excellent, 4 = non-assessable). Results: From 2085 coronary artery segments, 86.4% (1802/2085) were rated as having a score of 1, 12.3% (257/2085) as score of 2, 1.2% (26/2085) as score of 3, and none were rated as “non-assessable”. The average image quality score was 1.15 ± 0.26 on a per-segment basis. The effective dose was calculated by multiplying the coefficient factor of 0.028 by the dose–length product (DLP); the mean effective dose was 3.5 ± 0.8 mSv (range 1.7–7.6 mSv). The total dosage of contrast medium was 78.7 ± 2.9 ml. Conclusion: Double prospectively ECG-triggered high-pitch spiral acquisition mode provides good image quality with an average effective dose of less than 5 mSv in patients with a heart rate ≤70 bpm

  8. CT-guided biopsy of thoracic lesions with a novel wire-based needle guide device - initial experiences

    Energy Technology Data Exchange (ETDEWEB)

    Kroepil, Patric; Bilk, Philip; Quentin, Michael; Miese, Falk R; Lanzman, Rotem S; Scherer, Axel (Dept. of Radiology, Medical Faculty, Univ. Duesseldorf, Duesseldorf (Germany)), email: Patric.Kroepil@med.uni-duesseldorf.de

    2011-10-15

    Background Biopsies guided by computed tomography (CT) play an important role in clinical practice. A short duration, minimal radiation dose and complication rate are of particular interest. Purpose To evaluate the potential of a novel self-manufactured wire-based needle guide device for CT-guided thoracic biopsies with respect to radiation dose, intervention time and complication rate. Material and Methods Forty patients that underwent CT-guided biopsies of thoracic lesions were included in this study and assigned to two groups. Patients in group A (n = 20, mean age 69 +- 8.4 years) underwent biopsies with a novel wire-based needle guide device, while patients in group B (n = 20, mean age 68.4 +- 10.1 years) were biopsied without a needle guide device. The novel self-manufactured needle guide device consists of an iron/zinc wire modelled to a ring with a flexible arm and an eye at the end of the arm to stabilize the biopsy needle in the optimal position during intervention. Predefined parameters (radiation dose, number of acquired CT-slices, duration of intervention, complications) were compared between both groups. Results Mean radiation dose (CTDIvol 192 mGy versus 541 mGy; P = 0.001) and the number of acquired slices during intervention (n = 49 +- 33 vs. n = 126 +- 78; P = 0.001) were significantly lower in group A compared with group B. Intervention time in group A (13.1 min) was significantly lower than in group B (18.5 min, P < 0.01). A pneumothorax as peri-interventional complication was observed less frequent after device assisted biopsies (n = 4 vs. n = 8, n.s.). Conclusion The novel wire-based needle guide device is a promising tool to facilitate CT-guided thoracic biopsies reducing radiation dose, intervention time, and related complications. Further studies are mandatory to confirm these initial results

  9. CT-guided biopsy of thoracic lesions with a novel wire-based needle guide device - initial experiences

    International Nuclear Information System (INIS)

    Kroepil, Patric; Bilk, Philip; Quentin, Michael; Miese, Falk R; Lanzman, Rotem S; Scherer, Axel

    2011-01-01

    Background Biopsies guided by computed tomography (CT) play an important role in clinical practice. A short duration, minimal radiation dose and complication rate are of particular interest. Purpose To evaluate the potential of a novel self-manufactured wire-based needle guide device for CT-guided thoracic biopsies with respect to radiation dose, intervention time and complication rate. Material and Methods Forty patients that underwent CT-guided biopsies of thoracic lesions were included in this study and assigned to two groups. Patients in group A (n = 20, mean age 69 ± 8.4 years) underwent biopsies with a novel wire-based needle guide device, while patients in group B (n = 20, mean age 68.4 ± 10.1 years) were biopsied without a needle guide device. The novel self-manufactured needle guide device consists of an iron/zinc wire modelled to a ring with a flexible arm and an eye at the end of the arm to stabilize the biopsy needle in the optimal position during intervention. Predefined parameters (radiation dose, number of acquired CT-slices, duration of intervention, complications) were compared between both groups. Results Mean radiation dose (CTDIvol 192 mGy versus 541 mGy; P = 0.001) and the number of acquired slices during intervention (n = 49 ± 33 vs. n = 126 ± 78; P = 0.001) were significantly lower in group A compared with group B. Intervention time in group A (13.1 min) was significantly lower than in group B (18.5 min, P < 0.01). A pneumothorax as peri-interventional complication was observed less frequent after device assisted biopsies (n = 4 vs. n = 8, n.s.). Conclusion The novel wire-based needle guide device is a promising tool to facilitate CT-guided thoracic biopsies reducing radiation dose, intervention time, and related complications. Further studies are mandatory to confirm these initial results

  10. Initial Experience in Colombia in Patients with PET/CT-FDG Studies of the Central Nervous System

    International Nuclear Information System (INIS)

    Ucros, Gonzalo; Bernal, Patricia; Bermudez Sonia

    2009-01-01

    To describe the experience of patients who underwent a brain PET-CT during sixteen consecutive months. Method: 41 studies were made using flourodeoxiglucose (FDG) and registered with computed tomography. Results: These studies correspond to 5% of all PET studies performed at our institution. The age of patients ranged from 11 to 74 years. The main indications were: search for an epileptic focus (34%), cognitive disorder (32%), tumor evaluation (22%) and others (12%). Conclusion: The main applications of the brain PETCT FDG in our patients were: evaluation of untreatable epileptic patients thinking of undergoing surgery, evaluation of patients with cognitive disorders like Alzheimer's and other related dementias and finally, evaluation of patients with residual or primary brain tumors. It is among these patients in which this diagnostic modality has better diagnostic utility with abnormal findings, useful for their management.

  11. Functional imaging in differentiating bronchial masses: an initial experience with a combination of (18)F-FDG PET-CT scan and (68)Ga DOTA-TOC PET-CT scan.

    Science.gov (United States)

    Kumar, Arvind; Jindal, Tarun; Dutta, Roman; Kumar, Rakesh

    2009-10-01

    To evaluate the role of combination of (18)F-FDG PET-CT scan and (68)Ga DOTA-TOC PET-CT scan in differentiating bronchial tumors observed in contrast enhanced computed tomography scan of chest. Prospective observational study. Place of study: All India Institute of Medical Sciences, New Delhi, India. 7 patients with bronchial mass detected in computed tomography scan of the chest were included in this study. All patients underwent (18)F-FDG PET-CT scan, (68)Ga DOTA-TOC PET-CT scan and fiberoptic bronchoscope guided biopsy followed by definitive surgical excision. The results of functional imaging studies were analyzed and the results are correlated with the final histopathology of the tumor. Histopathological examination of 7 bronchial masses revealed carcinoid tumors (2 typical, 1 atypical), inflammatory myofibroblastic tumor (1), mucoepidermoid carcinoma (1), hamartoma (1), and synovial cell sarcoma (1). The typical carcinoids had mild (18)F-FDG uptake and high (68)Ga DOTA-TOC uptake. Atypical carcinoid had moderate uptake of (18)F-FDG and high (68)Ga DOTA-TOC uptake. Inflammatory myofibroblastic tumor showed high uptake of (18)F-FDG and no uptake of (68)Ga DOTA-TOC. Mucoepidermoid carcinoma showed mild (18)F-FDG uptake and no (68)Ga DOTA-TOC uptake. Hamartoma showed no uptake on either scans. Synovial cell sarcoma showed moderate (18)F-FDG uptake and mild focal (68)Ga DOTA-TOC uptake. This initial experience with the combined use of (18)F-FDG and (68)Ga DOTA-TOC PET-CT scan reveals different uptake patterns in various bronchial tumors. Bronchoscopic biopsy will continue to be the gold standard; however, the interesting observations made in this study merits further evaluation of the utility of the combination of (18)F-FDG PET-CT scan and (68)Ga DOTA-TOC PET-CT scan in larger number of patients with bronchial masses.

  12. Collateral Ventilation to Congenital Hyperlucent Lung Lesions Assessed on Xenon-Enhanced Dynamic Dual-Energy CT: an Initial Experience

    OpenAIRE

    Goo, Hyun Woo; Yang, Dong Hyun; Kim, Namkug; Park, Seung Il; Kim, Dong Kwan; Kim, Ellen Ai-Rhan

    2011-01-01

    Objective We wanted to evaluate the resistance to collateral ventilation in congenital hyperlucent lung lesions and to correlate that with the anatomic findings on xenon-enhanced dynamic dual-energy CT. Materials and Methods Xenon-enhanced dynamic dual-energy CT was successfully and safely performed in eight children (median age: 5.5 years, 4 boys and 4 girls) with congenital hyperlucent lung lesions. Functional assessment of the lung lesions on the xenon map was done, including performing a ...

  13. Collateral ventilation to congenital hyperlucent lung lesions assessed on xenon-enhanced dynamic dual-energy CT: an initial experience.

    Science.gov (United States)

    Goo, Hyun Woo; Yang, Dong Hyun; Kim, Namkug; Park, Seung Il; Kim, Dong Kwan; Kim, Ellen Ai-Rhan

    2011-01-01

    We wanted to evaluate the resistance to collateral ventilation in congenital hyperlucent lung lesions and to correlate that with the anatomic findings on xenon-enhanced dynamic dual-energy CT. Xenon-enhanced dynamic dual-energy CT was successfully and safely performed in eight children (median age: 5.5 years, 4 boys and 4 girls) with congenital hyperlucent lung lesions. Functional assessment of the lung lesions on the xenon map was done, including performing a time-xenon value curve analysis and assessing the amplitude of xenon enhancement (A) value, the rate of xenon enhancement (K) value and the time of arrival value. Based on the A value, the lung lesions were categorized into high or low (A value > 10 Hounsfield unit [HU]) resistance to collateral ventilation. In addition, the morphologic CT findings of the lung lesions, including cyst, mucocele and an accessory or incomplete fissure, were assessed on the weighted-average CT images. The xenon-enhanced CT radiation dose was estimated. Five of the eight lung lesions were categorized into the high resistance group and three lesions were categorized into the low resistance group. The A and K values in the normal lung were higher than those in the low resistance group. The time of arrival values were delayed in the low resistance group. Cysts were identified in five lesions, mucocele in four, accessory fissure in three and incomplete fissure in two. Either cyst or an accessory fissure was seen in four of the five lesions showing high resistance to collateral ventilation. The xenon-enhanced CT radiation dose was 2.3 ± 0.6 mSv. Xenon-enhanced dynamic dual-energy CT can help visualize and quantitate various degrees of collateral ventilation to congenital hyperlucent lung lesions in addition to assessing the anatomic details of the lung.

  14. High-pitch dual-source CT angiography of the whole aorta without ECG synchronisation: Initial experience

    International Nuclear Information System (INIS)

    Beeres, Martin; Schell, Boris; Mastragelopoulos, Aristidis; Kerl, Josef Matthias; Gruber-Rouh, Tatjana; Lee, Clara; Siebenhandl, Petra; Bodelle, Boris; Zangos, Stephan; Vogl, Thomas J.; Jacobi, Volkmar; Bauer, Ralf W.; Herrmann, Eva

    2012-01-01

    To investigate the feasibility, image quality and radiation dose for high-pitch dual-source CT angiography (CTA) of the whole aorta without ECG synchronisation. Each group of 40 patients underwent CTA either on a 16-slice (group 1) or dual-source CT device with conventional single-source (group 2) or high-pitch mode with a pitch of 3.0 (group 3). The presence of motion or stair-step artefacts of the thoracic aorta was independently assessed by two readers. Subjective and objective scoring of motion and artefacts were significantly reduced in the high-pitch examination protocol (p < 0.05). The imaging length was not significantly different, but the imaging time was significantly (p < 0.001) shorter in the high-pitch group (12.2 vs. 7.4 vs. 1.7 s for groups 1, 2 and 3). The ascending aorta and the coronary ostia were reliably evaluable in all patients of group 3 without motion artefacts as well. High-pitch dual-source CT angiography of the whole aorta is feasible in unselected patients. As a significant advantage over regular pitch protocols, motion-free imaging of the aorta is possible without ECG synchronisation. Thus, this CT mode bears potential to become a standard CT protocol before trans-catheter aortic valve implantation (TAVI). (orig.)

  15. Intra-arterial CT-angiography for cerebral arteriovenous malformation--initial experiences for treatment planning of radiosurgery

    International Nuclear Information System (INIS)

    Kunieda, Etsuo; Kawaguchi, Osamu; Onozuka, Satoshi; Momoshima, Suketaka; Takeda, Atsuya; Shigematsu, Naoyuki; Hashimoto, Subaru; Ohira, Takayuki; Kubo, Atsushi

    2002-01-01

    Purpose: To clarify the feasibility and effectiveness of intra-arterial CT angiography (IACTA) for treatment planning of arteriovenous malformation radiosurgery. Methods and Materials: A CT scanner installed in an angiographic examination room was used. Helical IACTA was performed in 22 patients during continuous intra-arterial infusion of contrast medium via the internal carotid or vertebral artery, and dynamic IACTA was performed in 20 of these patients with reconstruction at 0.2-s intervals. The dynamic IACTA was repeated for each 3- or 5-mm increment to encompass the nidus. Subtractions were performed in postembolization cases. A retrospective review of IACTA was performed to assess the effectiveness of dynamic scans. Results: No complications related to the angiographic procedure or CT imaging were detected. High contrast enhancement was obtained for both helical and dynamic IACTA. In 18 of the 20 cases (90%), draining veins were separated from the nidus by using the enhancement patterns, and in 13 cases (65%), feeding arteries were separated. Conclusion: Dynamic IACTA added important information for target-volume determinations. Conventional CT and MRI could be omitted from the protocol, and the period that patients wore the frame was substantially shortened. We conclude that IACTA is a practical and useful method for radiosurgical treatment planning of arteriovenous malformations

  16. CT Imaging for Evaluation of Calcium Crystal Deposition in the Knee: Initial Experience from The Multicenter Osteoarthritis (MOST) Study

    Science.gov (United States)

    Misra, Devyani; Guermazi, Ali; Sieren, Jered P.; Lynch, John; Torner, James; Neogi, Tuhina; Felson, David T.

    2014-01-01

    Objective Role of intra-articular calcium crystals in osteoarthritis (OA) is unclear. Imaging modalities used to date for its evaluation have limitations in their ability to fully characterize intra-articular crystal deposition. Since Computed Tomography (CT) imaging provides excellent visualization of bones and calcified tissue, in this pilot project we evaluated the utility of CT scan in describing intra-articular calcium crystal deposition in the knees. Method We included 12 subjects with and 4 subjects without radiographic chondrocalcinosis in the most recent visit from the Multicenter Osteoarthritis (MOST) study, which is a longitudinal cohort of community-dwelling older adults with or at risk for knee OA. All subjects underwent CT scans of bilateral knees. Each knee was divided into 25 subregions and each subregion was read for presence of calcium crystals by a musculoskeletal radiologist. To assess reliability, readings were repeated 4 weeks later. Results CT images permitted visualization of 25 subregions with calcification within and around the tibio-femoral and patello-femoral joints in all 24 knees with radiographic chondrocalcinosis. Intra-articular calcification was seen universally including meniscal cartilage (most common site involved in 21/24 knees), hyaline cartilage, cruciate ligaments, medial collateral ligament and joint capsule. Readings showed good agreement for specific tissues involved with calcium deposition (kappa: 0.70, 95% CI 0.62–0.80). Conclusion We found CT scan to be a useful and reliable tool for describing calcium crystal deposition in the knee and therefore potentially for studying role of calcium crystals in OA. We also confirmed that “chondrocalcinosis” is a misnomer because calcification is present ubiquitously. PMID:25451303

  17. 18F-DOPA PET and enhanced CT imaging for congenital hyperinsulinism: initial UK experience from a technologist's perspective.

    Science.gov (United States)

    Meintjes, Marguerite; Endozo, Raymond; Dickson, John; Erlandsson, Kjel; Hussain, Khalid; Townsend, Caroline; Menezes, Leon; Bomanji, Jamshed

    2013-06-01

    Congenital hyperinsulinism (CHI) is the most common cause of persistent hypoglycaemia in infants and children. Histologically, there are two subgroups, diffuse and focal. The aim of this study was to evaluate the accuracy of (18)F-fluoro-L-dihydroxyphenylalanine ((18)F-DOPA) PET/computed tomography (CT) and contrast-enhanced CT in distinguishing between focal and diffuse lesions in infants with CHI who are unresponsive to medical therapy. In addition, this paper describes the detailed protocol used for imaging and analysis of (18)F-DOPA PET/CT images in our clinical practice. Twenty-two (18)F-DOPA PET/CT and contrast-enhanced CT imaging studies were carried out on 18 consecutive patients (nine boys and nine girls) with CHI (median age, 2 years and 1 month; range, 1-84 months) who had positive dominant ABCC8 mutation genetic results or negative ABCC8/t results but did not respond to first-line medical therapy with high-dose diazoxide. (18)F-DOPA was produced by the cyclotron unit of Woolfson Molecular Imaging Centre, Manchester, and transported to our centre in central London after synthesis and implementation of quality control measures. (18)F-DOPA was administered intravenously at a dose of 4 MBq/kg, and iodine contrast medium was injected intravenously at a dose of 1.5 ml/kg. Single bed position PET/CT images of the pancreas were acquired under light sedation with oral chloral hydrate. Four PET dynamic data acquisition scans were taken 20, 40, 50 and 60 min after injection for a duration of 10 min each. The results were assessed by visual interpretation and quantitative measurements of standardized uptake values (SUVs) in the head, body, and tail of the pancreas. Of the 18 patients, 13 showed diffuse and five showed focal (18)F-DOPA PET pancreatic uptake. Three regions of interest were drawn over the head, body and tail of the pancreas to calculate the SUV(max). Using the formula - highest SUV(max)/next highest SUV(max) - a ratio was calculated. Five patients had

  18. Dual-energy CT in the evaluation of solitary pulmonary nodules by virtual non-enhanced images: initial experience

    International Nuclear Information System (INIS)

    Guo Xing; Ding Wei; Qin Huijuan

    2011-01-01

    Objective: To determine the accuracy and radiation dose of dual-energy computed tomography (CT) in evaluating solitary pulmonary nodules (SPNs) by virtual non-enhanced images. Methods: Sixty-one patients with SPNs including 39 malignant and 18 benign nodules proved by pathology underwent DECT scans. The CT values of SPNs on enhanced weighted average and virtual non-enhanced images were compared by using Liver VNC processing unit in terms of their diagnostic accuracy for distinguishing malignant and benign nodules with a 20 HU threshold. Diagnostic accuracy was compared. In 28 patients of all patients, image noise and quality score of the non-enhanced and virtual non-enhanced images were compared, and radiation doses of each patient were recorded. The paired t test was used to analyze the noise difference between the plain scan and virtual non-enhanced scan. The Mann-Whitney U test. was used to analyze statistically significant differences of the image quality score and radiation dose between the non-enhanced scan and virtual non-enhanced scan. Results: The sensitivity, specificity and accuracy for distinguishing benign and malignant nodules by using the virtual non-enhanced image of were 89.7% (35/39), 72.2% (13/18), 84.2% (48/57) respectively. The noise of common CT and virtual non- enhanced images were (8.49±1.94) HU and (10.14±2.18) HU, and there were statistically difference (t=9.45, P 0.05). The radiation doses of common CT and DECT were (3.72±0.48) mSv and (3.78±0.45) mSv, and there were no statistical difference (U= 350.50, P>0.05). Conclusion: DECT by using virtual non-enhanced images is useful tool to distinguish the benign and malignant SPN without additional radiation dose. (authors)

  19. CT-Guided Percutaneous Drainage of Infected Collections Due to Gastric Leak After Sleeve Gastrectomy for Morbid Obesity: Initial Experience

    International Nuclear Information System (INIS)

    Kelogrigoris, M.; Sotiropoulou, E.; Stathopoulos, K.; Georgiadou, V.; Philippousis, P.; Thanos, L.

    2011-01-01

    This study was designed to evaluate the efficacy and safety of computed tomography (CT)-guided drainage in treating infected collections due to gastric leak after laparoscopic sleeve gastrectomy for morbid obesity. From January 2007 to June 2009, 21 patients (9 men and 12 women; mean age, 39.2 (range, 26–52) years) with infected collections due to gastric leak after laparoscopic sleeve gastrectomy for morbid obesity underwent image-guided percutaneous drainage. All procedures were performed using CT guidance and 8- to 12-Fr pigtail drainage catheters. Immediate technical success was achieved in all 21 infected collections. In 18 of 21 collections, we obtained progressive shrinkage of the collection with consequent clinical success (success rate 86%). In three cases, the abdominal fluid collection was not resolved, and the patients were reoperated. Among the 18 patients who avoided surgery, 2 needed replacement of the catheter due to obstruction. No major complications occurred during the procedure. The results of our study support that CT-guided percutaneous drainage is an effective and safe method to treat infected abdominal fluid collections due to gastric leak in patients who had previously underwent laparoscopic sleeve gastrectomy for morbid obesity. It may be considered both as a preparatory step for surgery and a valuable alternative to open surgery. Failure of the procedure does not, however, preclude a subsequent surgical operation.

  20. Evaluation of dual energy spectral CT in differentiating metastatic from non-metastatic lymph nodes in rectal cancer: Initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Huanhuan [Department of Radiology, Ruijin Hospital Affiliated to Shanghai Jiaotong University, School of Medicine, Shanghai 200025 (China); Department of Radiology, Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine (China); Yan, Fuhua; Pan, Zilai; Lin, Xiaozhu; Luo, Xianfu; Shi, Cen [Department of Radiology, Ruijin Hospital Affiliated to Shanghai Jiaotong University, School of Medicine, Shanghai 200025 (China); Chen, Xiaoyan [Department of Pathology, Ruijin Hospital Affiliated to Shanghai Jiaotong University, School of Medicine, Shanghai 200025 (China); Wang, Baisong [Department of Biomedical Statistics, Shanghai Jiaotong University, School of Medicine, Shanghai 200025 (China); Zhang, Huan, E-mail: huanzhangy@126.com [Department of Radiology, Ruijin Hospital Affiliated to Shanghai Jiaotong University, School of Medicine, Shanghai 200025 (China)

    2015-02-15

    Highlights: • Colorectal cancer is the third most prevalent cancer and the status of the regional lymph nodes in rectal cancer is considered to be one of the most powerful prognostic factor in the absence of distant metastatic disease. Detecting LNs metastasis is still a challenging problem due to the presence of microscopic metastasis or inflammatory swelling of LNs. • We investigated the value of dual energy spectral CT in differentiating metastatic from non-metastatic lymph nodes in rectal cancer. Our study demonstrated that the quantitative normalized iodine concentration (nIC) could be useful for differentiating metastatic and non-metastatic lymph nodes. The combination of nIC in portal venous phase and conventional size criterion could improve the diagnostic accuracy, sensitivity, specificity, positive predictive value and negative predictive value of rectal cancer. - Abstract: Objectives: To investigate the value of dual energy spectral CT (DEsCT) imaging in differentiating metastatic from non-metastatic lymph nodes in rectal cancer. Methods: Fifty-five patients with rectal cancer underwent the arterial phase (AP) and portal venous phase (PP) contrast-enhanced DEsCT imaging. The virtual monochromatic images and iodine-based material decomposition images derived from DEsCT imaging were interpreted for lymph nodes (LNs) measurement. The short axis diameter and the normalized iodine concentration (nIC) of metastatic and non-metastatic LNs were measured. The two-sample t test was used to compare the short axis diameters and nIC values of metastatic and non-metastatic LNs. ROC analysis was performed to assess the diagnostic performance. Results: One hundred and fifty two LNs including 92 non-metastatic LNs and 60 metastatic LNs were matched using the radiological-pathological correlation. The mean short axis diameter of metastatic LNs was significantly larger than that of the non-metastatic LNs (7.28 ± 2.28 mm vs. 4.90 ± 1.64 mm, P < 0.001). The mean n

  1. Diagnosing and quantification of acute alcohol intoxication. Comparison of dual-energy CT with biochemical analysis. Initial experience

    International Nuclear Information System (INIS)

    Korkusuz, H.; Abbas Raschidi, B.; Keese, D.; Kromen, W.; Bauer, R.W.; Vogl, T.J.; Namgaladze, D.

    2012-01-01

    Purpose: To quantify the correlation between fat content of an acute alcohol intoxication and the difference of computer tomography attenuation value in dual-energy CT in comparison to biochemical triglyceride analysis and to evaluate qualitatively the value of DECT in the diagnosis of fatty liver caused by ethanol-dosage in rats. Materials and Methods: DECT at 140 kV and 80 kV was performed on 20 rats before and two days after the administration of 3 ml of 50 % ethanol. The CT attenuation value in the livers at 140 kV, 80 kV and the differences between them in Hounsfield units (ΔH) were collected. Parts of the liver (100 mg) were measured in biochemical triglyceride analysis as the reference standard. A blood sample was also taken to measure specific liver enzymes. Results: Linear correlation between biochemical triglyceride analysis and CT density of ΔH was found (r = 0.949). 140 kV attenuation data were between 44 HU and 61.3 HU, 80 kV attenuation data were between 58.4 HU and 64.7 HU, and ΔH data were between 3.4 HU and 14.4 HU (p ≤ 0.037). The biochemical triglyceride analysis data were between 7.1 mg/g and 41.1 mg/g. The hepatic enzymes serum aspartate (ASAT) aminotransferase and alanine aminotransferase (ALAT) were elevated in all rats. ASAT correlated directly with ΔHU (r = -0.86). Conclusion: DECT provides a non-invasive method to determine and evaluate hepatic fat content after acute alcohol intoxication. It provides the possibility to detect and quantify the hepatic fat content of liver graft. (orig.)

  2. Automatic spectral imaging protocol selection and iterative reconstruction in abdominal CT with reduced contrast agent dose: initial experience.

    Science.gov (United States)

    Lv, Peijie; Liu, Jie; Chai, Yaru; Yan, Xiaopeng; Gao, Jianbo; Dong, Junqiang

    2017-01-01

    To evaluate the feasibility, image quality, and radiation dose of automatic spectral imaging protocol selection (ASIS) and adaptive statistical iterative reconstruction (ASIR) with reduced contrast agent dose in abdominal multiphase CT. One hundred and sixty patients were randomly divided into two scan protocols (n = 80 each; protocol A, 120 kVp/450 mgI/kg, filtered back projection algorithm (FBP); protocol B, spectral CT imaging with ASIS and 40 to 70 keV monochromatic images generated per 300 mgI/kg, ASIR algorithm. Quantitative parameters (image noise and contrast-to-noise ratios [CNRs]) and qualitative visual parameters (image noise, small structures, organ enhancement, and overall image quality) were compared. Monochromatic images at 50 keV and 60 keV provided similar or lower image noise, but higher contrast and overall image quality as compared with 120-kVp images. Despite the higher image noise, 40-keV images showed similar overall image quality compared to 120-kVp images. Radiation dose did not differ between the two protocols, while contrast agent dose in protocol B was reduced by 33 %. Application of ASIR and ASIS to monochromatic imaging from 40 to 60 keV allowed contrast agent dose reduction with adequate image quality and without increasing radiation dose compared to 120 kVp with FBP. • Automatic spectral imaging protocol selection provides appropriate scan protocols. • Abdominal CT is feasible using spectral imaging and 300 mgI/kg contrast agent. • 50-keV monochromatic images with 50 % ASIR provide optimal image quality.

  3. Automatic spectral imaging protocol selection and iterative reconstruction in abdominal CT with reduced contrast agent dose: initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Peijie; Liu, Jie; Chai, Yaru; Yan, Xiaopeng; Gao, Jianbo; Dong, Junqiang [The First Affiliated Hospital of Zhengzhou University, Department of Radiology, Zhengzhou, Henan Province (China)

    2017-01-15

    To evaluate the feasibility, image quality, and radiation dose of automatic spectral imaging protocol selection (ASIS) and adaptive statistical iterative reconstruction (ASIR) with reduced contrast agent dose in abdominal multiphase CT. One hundred and sixty patients were randomly divided into two scan protocols (n = 80) each; protocol A, 120 kVp/450 mgI/kg, filtered back projection algorithm (FBP); protocol B, spectral CT imaging with ASIS and 40 to 70 keV monochromatic images generated per 300 mgI/kg, ASIR algorithm. Quantitative parameters (image noise and contrast-to-noise ratios [CNRs]) and qualitative visual parameters (image noise, small structures, organ enhancement, and overall image quality) were compared. Monochromatic images at 50 keV and 60 keV provided similar or lower image noise, but higher contrast and overall image quality as compared with 120-kVp images. Despite the higher image noise, 40-keV images showed similar overall image quality compared to 120-kVp images. Radiation dose did not differ between the two protocols, while contrast agent dose in protocol B was reduced by 33 %. Application of ASIR and ASIS to monochromatic imaging from 40 to 60 keV allowed contrast agent dose reduction with adequate image quality and without increasing radiation dose compared to 120 kVp with FBP. (orig.)

  4. Automatic spectral imaging protocol selection and iterative reconstruction in abdominal CT with reduced contrast agent dose: initial experience

    International Nuclear Information System (INIS)

    Lv, Peijie; Liu, Jie; Chai, Yaru; Yan, Xiaopeng; Gao, Jianbo; Dong, Junqiang

    2017-01-01

    To evaluate the feasibility, image quality, and radiation dose of automatic spectral imaging protocol selection (ASIS) and adaptive statistical iterative reconstruction (ASIR) with reduced contrast agent dose in abdominal multiphase CT. One hundred and sixty patients were randomly divided into two scan protocols (n = 80) each; protocol A, 120 kVp/450 mgI/kg, filtered back projection algorithm (FBP); protocol B, spectral CT imaging with ASIS and 40 to 70 keV monochromatic images generated per 300 mgI/kg, ASIR algorithm. Quantitative parameters (image noise and contrast-to-noise ratios [CNRs]) and qualitative visual parameters (image noise, small structures, organ enhancement, and overall image quality) were compared. Monochromatic images at 50 keV and 60 keV provided similar or lower image noise, but higher contrast and overall image quality as compared with 120-kVp images. Despite the higher image noise, 40-keV images showed similar overall image quality compared to 120-kVp images. Radiation dose did not differ between the two protocols, while contrast agent dose in protocol B was reduced by 33 %. Application of ASIR and ASIS to monochromatic imaging from 40 to 60 keV allowed contrast agent dose reduction with adequate image quality and without increasing radiation dose compared to 120 kVp with FBP. (orig.)

  5. CT urography in women with primary or recurrent pelvic tumors. Background and initial experiences; CT-Urographie bei Frauen mit primaeren oder rezidivierenden Beckentumoren. Hintergrund und erste Erfahrungen

    Energy Technology Data Exchange (ETDEWEB)

    Seifert, S.; Mueller-Lisse, U.G.; Degenhart, C.; Mourched, F.; Reiser, M.F. [Klinikum der Ludwig-Maximilians-Universitaet, Campus Innenstadt, Institut fuer Klinische Radiologie, Muenchen (Germany); Jundt, K. [Klinikum der Ludwig-Maximilians-Universitaet, Campus Innenstadt, Klinik und Poliklinik fuer Gynaekologie und Geburtshilfe, Muenchen (Germany); Stief, C.G.; Mueller-Lisse, U.L. [Klinikum der Ludwig-Maximilians-Universitaet, Campus Innenstadt, Klinik und Poliklinik fuer Urologie, Muenchen (Germany)

    2011-07-15

    Malignant tumors of the female pelvis account for 12-13% of newly diagnosed solid neoplasms among women in the USA and Germany. German guidelines advocate diagnostic imaging for local recurrence and metastasis while there are no recommendations for primary tumors. As excretory urography has been replaced by the excretory phase of computed tomography urography (CTU) in many institutions, two independent observers retrospectively evaluated CTUs of primary or recurrent female pelvic tumors to rule out associations between CTU findings and subsequent urologic measures. Among 31 CTUs of 27 women (age 29-84 years, mean 57 years) with 15 primary and 13 recurrent tumors, 83-100% of unremarkable proximal, middle and distal ureter segments were completely delineated in the excretory phase (delay 6-29 min, mean 16 min). The most common pathological findings included distal ureter obstruction (n=19, 61%), bladder compression (n=13, 42%) and bladder invasion (n=8, 26%). Out of 20 pathologically altered urinary tracts 8 were subsequently subjected to urologic measures (2-tailed Fisher exact test, p=0.0215) but none of the 10 unremarkable urinary tracts were treated. It appears that CTU is a sensible pre-therapeutic test for the urinary tract for primary and recurrent female pelvic tumors. (orig.) [German] Maligne Beckentumoren stellen 12-13% aller neu diagnostizierten soliden Neoplasien bei Frauen in den USA und in Deutschland dar. Deutsche Leitlinien befuerworten bildgebende Untersuchungen bei Lokalrezidiven und Metastasen; fuer Primaertumoren gibt es keine einschlaegigen Empfehlungen. Da das Ausscheidungsurogramm durch die Ausscheidungsaufnahme der CT-Urographie (CTU) weitgehend abgeloest ist, wurde bei weiblichen Beckentumoren oder deren Rezidive der Zusammenhang zwischen CTU-Befunden und nachfolgenden operativen urologischen Massnahmen retrospektiv von 2 unabhaengigen Auswertern geprueft. Bei 31 CTUs von 27 Frauen (Alter 29-84, Median 57 Jahre) mit 15 Primaertumoren und 13

  6. Coronary CT angiography-derived fractional flow reserve correlated with invasive fractional flow reserve measurements - initial experience with a novel physician-driven algorithm

    International Nuclear Information System (INIS)

    Baumann, Stefan; Wang, Rui; Schoepf, U.J.; Steinberg, Daniel H.; Spearman, James V.; Bayer, Richard R.; Hamm, Christian W.; Renker, Matthias

    2015-01-01

    The present study aimed to determine the feasibility of a novel fractional flow reserve (FFR) algorithm based on coronary CT angiography (cCTA) that permits point-of-care assessment, without data transfer to core laboratories, for the evaluation of potentially ischemia-causing stenoses. To obtain CT-based FFR, anatomical coronary information and ventricular mass extracted from cCTA datasets were integrated with haemodynamic parameters. CT-based FFR was assessed for 36 coronary artery stenoses in 28 patients in a blinded fashion and compared to catheter-based FFR. Haemodynamically relevant stenoses were defined by an invasive FFR ≤0.80. Time was measured for the processing of each cCTA dataset and CT-based FFR computation. Assessment of cCTA image quality was performed using a 5-point scale. Mean total time for CT-based FFR determination was 51.9 ± 9.0 min. Per-vessel analysis for the identification of lesion-specific myocardial ischemia demonstrated good correlation (Pearson's product-moment r = 0.74, p < 0.0001) between the prototype CT-based FFR algorithm and invasive FFR. Subjective image quality analysis resulted in a median score of 4 (interquartile ranges, 3-4). Our initial data suggest that the CT-based FFR method for the detection of haemodynamically significant stenoses evaluated in the selected population correlates well with invasive FFR and renders time-efficient point-of-care assessment possible. (orig.)

  7. Initial thoracic involvement in lymphoma. CT assessment

    International Nuclear Information System (INIS)

    Bustos, A.; Corredoira, J.; Ferreiros, J.; Cabeza, B.; Jorquera, M.; Pedrosa, I.; Martinez, R.; Fernandez, C.

    2002-01-01

    To analyze the initial thoracic involvement by CT in a consecutive series of patients with lymphoma. A retrospective analysis was made of thoracic CT studies made at the time of diagnosis of 259 patients with lymphoma. Mediastinal pulmonary, pleural, pericardial and chest wall involvement was assessed by CT. Of 259 patients (129 men y 130 women), 56 had Hodgkin's disease (HD) and 203 had non-Hodgkin lymphoma (NHL). Forty-two percent (42.5%, 110/259) of the patients had chest involvement on CT: 33 of 56 patients with HD (58.9%) and 77 of 203 patients with NHL (37.9%). All the patients with thoracic HD) and 71.4% of patients with thoracic NHL, had mediastinal lymph node involvement. of the patients with thoracic involvement 12.1% (4/33) of the patient with HD and 23.3% (18/77) of the patients with NHL had pulmonary involvement. Thoracic involvement on CT was more frequent in HD. Mediastinal lymph node involvement was the most common finding fundamentally in HD. Pulmonary disease always occurred in the presence of mediastinal lymph node involvement in HD but could occur as an isolated finding in NHL. (Author) 24 refs

  8. Using multidetector-row CT in neonates with complex congenital heart disease to replace diagnostic cardiac catheterization for anatomical investigation: initial experiences in technical and clinical feasibility

    International Nuclear Information System (INIS)

    Lee, Tain; Tsai, I.C.; Chen, Min-Chi; Fu, Yun-Ching; Jan, Sheng-Lin; Wang, Chung-Chi; Chang, Yen

    2006-01-01

    Echocardiography is the first-line modality for the investigation of neonatal congenital heart disease. Diagnostic cardiac catheterization, which has a small but recognized risk, is usually performed if echocardiography fails to provide a confident evaluation of the lesions. To verify the technical and clinical feasibilities of replacing diagnostic cardiac catheterization with multidetector-row CT (MDCT) in neonatal complex congenital heart disease. Over a 1-year period we prospectively enrolled all neonates with complex congenital heart disease referred for diagnostic cardiac catheterization after initial assessment by echocardiography. MDCT was performed using a 40-detector-row CT scanner with dual syringe injection. A multidisciplinary congenital heart disease team evaluated the MDCT images and decided if further diagnostic cardiac catheterization was necessary. The accuracy of MDCT in detecting separate cardiovascular anomalies and bolus geometry of contrast enhancement were calculated. A total of 14 neonates were included in the study. No further diagnostic cardiac catheterization was needed in any neonate. The accuracy of MDCT in diagnosing separate cardiovascular anomalies was 98% (53/54) with only one atrial septal defect missed in a patient with coarctation syndrome. The average cardiovascular enhancement in evaluated chambers was 471 HU. No obvious beam-hardening artefact was observed. The technical and clinical feasibility of MDCT in complex congenital heart disease in neonates is confirmed. After initial assessment with echocardiography, MDCT could probably replace diagnostic cardiac catheterization for further anatomical clarification in neonates. (orig.)

  9. Combined electrocardiography- and respiratory-triggered CT of the lung to reduce respiratory misregistration artifacts between imagining slabs in free-breathing children: Initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of); Allmendinger, Thomas [Siemens Healthcare, GmbH, Computed Tomography Division, Forchheim (Germany)

    2017-09-15

    Cardiac and respiratory motion artifacts degrade the image quality of lung CT in free-breathing children. The aim of this study was to evaluate the effect of combined electrocardiography (ECG) and respiratory triggering on respiratory misregistration artifacts on lung CT in free-breathing children. In total, 15 children (median age 19 months, range 6 months–8 years; 7 boys), who underwent free-breathing ECG-triggered lung CT with and without respiratory-triggering were included. A pressure-sensing belt of a respiratory gating system was used to obtain the respiratory signal. The degree of respiratory misregistration artifacts between imaging slabs was graded on a 4-point scale (1, excellent image quality) on coronal and sagittal images and compared between ECG-triggered lung CT studies with and without respiratory triggering. A p value < 0.05 was considered significant. Lung CT with combined ECG and respiratory triggering showed significantly less respiratory misregistration artifacts than lung CT with ECG triggering only (1.1 ± 0.4 vs. 2.2 ± 1.0, p = 0.003). Additional respiratory-triggering reduces respiratory misregistration artifacts on ECG-triggered lung CT in free-breathing children.

  10. Combined electrocardiography- and respiratory-triggered CT of the lung to reduce respiratory misregistration artifacts between imagining slabs in free-breathing children: Initial experience

    International Nuclear Information System (INIS)

    Goo, Hyun Woo; Allmendinger, Thomas

    2017-01-01

    Cardiac and respiratory motion artifacts degrade the image quality of lung CT in free-breathing children. The aim of this study was to evaluate the effect of combined electrocardiography (ECG) and respiratory triggering on respiratory misregistration artifacts on lung CT in free-breathing children. In total, 15 children (median age 19 months, range 6 months–8 years; 7 boys), who underwent free-breathing ECG-triggered lung CT with and without respiratory-triggering were included. A pressure-sensing belt of a respiratory gating system was used to obtain the respiratory signal. The degree of respiratory misregistration artifacts between imaging slabs was graded on a 4-point scale (1, excellent image quality) on coronal and sagittal images and compared between ECG-triggered lung CT studies with and without respiratory triggering. A p value < 0.05 was considered significant. Lung CT with combined ECG and respiratory triggering showed significantly less respiratory misregistration artifacts than lung CT with ECG triggering only (1.1 ± 0.4 vs. 2.2 ± 1.0, p = 0.003). Additional respiratory-triggering reduces respiratory misregistration artifacts on ECG-triggered lung CT in free-breathing children

  11. Comparison of PET/CT and PET/MRI hybrid systems using a 68Ga-labelled PSMA ligand for the diagnosis of recurrent prostate cancer: initial experience

    International Nuclear Information System (INIS)

    Afshar-Oromieh, A.; Haberkorn, U.; Schlemmer, H.P.; Fenchel, M.; Roethke, M.; Eder, M.; Eisenhut, M.; Hadaschik, B.A.; Kopp-Schneider, A.

    2014-01-01

    68 Ga-labelled HBED-CC-PSMA is a highly promising tracer for imaging recurrent prostate cancer (PCa). The intention of this study was to evaluate the feasibility of PET/MRI with this tracer. Twenty patients underwent PET/CT 1 h after injection of the 68 Ga-PSMA ligand followed by PET/MRI 3 h after injection. Data from the two investigations were first analysed separately and then compared with respect to tumour detection rate and radiotracer uptake in various tissues. To evaluate the quantification accuracy of the PET/MRI system, differences in SUVs between PET/CT and corresponding PET/MRI were compared with differences in SUVs between PET/CT 1 h and 3 h after injection in another patient cohort. This cohort was investigated using the same PET/CT system. With PET/MRI, different diagnostic sequences, higher contrast of lesions and higher resolution of MRI enabled a subjectively easier evaluation of the images. In addition, four unclear findings on PET/CT could be clarified as characteristic of PCa metastases by PET/MRI. However, in PET images of the PET/MRI, a reduced signal was observed at the level of the kidneys (in 11 patients) and around the urinary bladder (in 15 patients). This led to reduced SUVs in six lesions. SUV mean values provided by the PET/MRI system were different in muscles, blood pool, liver and spleen. PCa was detected more easily and more accurately with Ga-PSMA PET/MRI than with PET/CT and with lower radiation exposure. Consequently, this new technique could clarify unclear findings on PET/CT. However, scatter correction was challenging when the specific 68 Ga-PSMA ligand was used. Moreover, direct comparison of SUVs from PET/CT and PET/MR needs to be conducted carefully. (orig.)

  12. Initial Experience of Using Dual-Energy CT with an Iodine Overlay Image for Hand Psoriatic Arthritis: Comparison Study with Contrast-enhanced MR Imaging.

    Science.gov (United States)

    Fukuda, Takeshi; Umezawa, Yoshinori; Tojo, Shinjiro; Yonenaga, Takenori; Asahina, Akihiko; Nakagawa, Hidemi; Fukuda, Kunihiko

    2017-07-01

    Purpose To determine the feasibility of dual-energy (DE) computed tomography (CT) with an iodine overlay image (IOI) for evaluation of psoriatic arthritis in the hand. Materials and Methods Approval from the institutional ethics committee and written informed consent from all patients were obtained. This prospective study included 16 patients who had psoriasis with finger joint symptoms from January 2015 to January 2016. Contrast material-enhanced (CE) DE CT and 1.5-T CE magnetic resonance (MR) imaging were performed within 1 month of each other. DE CT was performed with a tube voltage of 80 kV and 140 kV with use of a 0.4-mm tin filter. Images acquired with both modalities were evaluated by two radiologists independently by using a semiquantitative scoring system. Interreader agreement was calculated for each modality: Weighted κ values were calculated for synovitis, flexor tenosynovitis, and extensor peritendonitis, and κ values were calculated for periarticular inflammation. With consensus scores and CE MR images as the reference, the sensitivity and specificity of IOI DE CT for inflammatory lesions were calculated. Statistical analysis of discordant readings was performed by using the McNemar test. Results Interreader agreement for inflammatory lesions was excellent or good (weighted κ = 0.83 and κ = 0.75 in IOI DE CT; weighted κ = 0.81 and κ = 0.87 in CE MR imaging). The sensitivity and specificity of IOI DE CT were 0.78 and 0.87, respectively. Total agreement was 86.3%; however, there were significantly more lesions detected with IOI DE CT than with CE MR imaging alone (134 vs 20 lesions in 1120 evaluated items; P the abnormalities detected with IOI DE CT alone were located in distal interphalangeal joints. Conclusion IOI DE CT is a new imaging modality that may be useful for evaluating psoriatic arthritis in the hand, particularly in the detection of inflammatory lesions in small joints, and may be more useful than CE MR imaging, within the limitation

  13. Initial experience with lung-MRI at 3.0 T: Comparison with CT and clinical data in the evaluation of interstitial lung disease activity

    Energy Technology Data Exchange (ETDEWEB)

    Lutterbey, G. [Department of Radiology, University of Bonn, Sigmund-Freud-Strasse 25, D-53105 Bonn (Germany)]. E-mail: goetz.lutterbey@ukb.uni-bonn.de; Grohe, C. [Department of Internal Medicine, University of Bonn (Germany); Gieseke, J. [PHILIPS Medical Systems, Best (Netherlands); Falkenhausen, M. von [Department of Radiology, University of Bonn, Sigmund-Freud-Strasse 25, D-53105 Bonn (Germany); Morakkabati, N. [Department of Radiology, University of Bonn, Sigmund-Freud-Strasse 25, D-53105 Bonn (Germany); Wattjes, M.P. [Department of Radiology, University of Bonn, Sigmund-Freud-Strasse 25, D-53105 Bonn (Germany); Manka, R. [Department of Internal Medicine, University of Bonn (Germany); Trog, D. [Department of Radiology, University of Bonn, Sigmund-Freud-Strasse 25, D-53105 Bonn (Germany); Schild, H.H. [Department of Radiology, University of Bonn, Sigmund-Freud-Strasse 25, D-53105 Bonn (Germany)

    2007-02-15

    Objectives: We evaluated the feasibility of highfield lung-MRI at 3.0 T. A comparison with Computed Tomography (CT) and clinical data regarding the assessment of inflammatory activity in patients with diffuse lung disease was performed. Material and methods: Prospective evaluation of 21 patients (15 males, 6 females, 43-80 y) with diffuse lung diseases who underwent clinical work-up inclusive laboratory tests, lung-function tests and transbronchial biopsy. After routine helical CT (additional 12 HRCT) a lung-MRI (3.0 Intera, Philips Medical Systems, Best, The Netherlands) using a T2-weighted, cardiac and respiratory triggered Fast-Spinecho-Sequence (TE/TR = 80/1500-2500 ms, 22 transverse slices, 7/2 mm slice-thickness/-gap) was performed. A pneumologist classified the cases into two groups: A = temporary acute interstitial disease or chronic interstitial lung disease with acute episode or superimposed infection/B = burned out interstitial lung disease without activity. Two blinded CT-radiologists graded the cases in active/inactive disease on the basis of nine morphological criteria each. A third radiologist rated the MRI-cases as active/inactive, depending on the signal-intensities of lung tissues. Results: The pneumologist classified 14 patients into group A and 7 patients into group B. Using CT, 6 cases were classified as active, 15 cases as inactive disease. With MRI 12 cases were classified as active and 9 cases as inactive. In the complete group of 21 patients MRI decisions and CT decisions respectively were false positive/false negative/correct in 2/4/15 respectively 0/8/13 cases. Correct diagnoses were obtained in 72% (MRI) respectively 62% (CT). In the subgroup of 12 cases including HRCT, MRI respectively CT were false positive/false negative/correct in 2/1/9 respectively 0/5/7 cases. Correct diagnoses were obtained in 75% (MRI) respectively 58% (CT). Conclusion: Highfield MRI of the lung is feasible and performed slightly better compared to CT in the

  14. Initial experience with lung-MRI at 3.0 T: Comparison with CT and clinical data in the evaluation of interstitial lung disease activity

    International Nuclear Information System (INIS)

    Lutterbey, G.; Grohe, C.; Gieseke, J.; Falkenhausen, M. von; Morakkabati, N.; Wattjes, M.P.; Manka, R.; Trog, D.; Schild, H.H.

    2007-01-01

    Objectives: We evaluated the feasibility of highfield lung-MRI at 3.0 T. A comparison with Computed Tomography (CT) and clinical data regarding the assessment of inflammatory activity in patients with diffuse lung disease was performed. Material and methods: Prospective evaluation of 21 patients (15 males, 6 females, 43-80 y) with diffuse lung diseases who underwent clinical work-up inclusive laboratory tests, lung-function tests and transbronchial biopsy. After routine helical CT (additional 12 HRCT) a lung-MRI (3.0 Intera, Philips Medical Systems, Best, The Netherlands) using a T2-weighted, cardiac and respiratory triggered Fast-Spinecho-Sequence (TE/TR = 80/1500-2500 ms, 22 transverse slices, 7/2 mm slice-thickness/-gap) was performed. A pneumologist classified the cases into two groups: A = temporary acute interstitial disease or chronic interstitial lung disease with acute episode or superimposed infection/B = burned out interstitial lung disease without activity. Two blinded CT-radiologists graded the cases in active/inactive disease on the basis of nine morphological criteria each. A third radiologist rated the MRI-cases as active/inactive, depending on the signal-intensities of lung tissues. Results: The pneumologist classified 14 patients into group A and 7 patients into group B. Using CT, 6 cases were classified as active, 15 cases as inactive disease. With MRI 12 cases were classified as active and 9 cases as inactive. In the complete group of 21 patients MRI decisions and CT decisions respectively were false positive/false negative/correct in 2/4/15 respectively 0/8/13 cases. Correct diagnoses were obtained in 72% (MRI) respectively 62% (CT). In the subgroup of 12 cases including HRCT, MRI respectively CT were false positive/false negative/correct in 2/1/9 respectively 0/5/7 cases. Correct diagnoses were obtained in 75% (MRI) respectively 58% (CT). Conclusion: Highfield MRI of the lung is feasible and performed slightly better compared to CT in the

  15. Assessment of regional lung functional impairment with co-registered respiratory-gated ventilation/perfusion SPET-CT images: initial experiences

    International Nuclear Information System (INIS)

    Suga, Kazuyoshi; Yasuhiko, Kawakami; Zaki, Mohammed; Yamashita, Tomio; Seto, Aska; Matsumoto, Tsuneo; Matsunaga, Naofumi

    2004-01-01

    In this study, respiratory-gated ventilation and perfusion single-photon emission tomography (SPET) were used to define regional functional impairment and to obtain reliable co-registration with computed tomography (CT) images in various lung diseases. Using a triple-headed SPET unit and a physiological synchroniser, gated perfusion SPET was performed in a total of 78 patients with different pulmonary diseases, including metastatic nodules (n=15); in 34 of these patients, it was performed in combination with gated technetium-99m Technegas SPET. Projection data were acquired using 60 stops over 120 for each detector. Gated end-inspiration and ungated images were reconstructed from 1/8 data centered at peak inspiration for each regular respiratory cycle and full respiratory cycle data, respectively. Gated images were registered with tidal inspiration CT images using automated three-dimensional (3D) registration software. Registration mismatch was assessed by measuring 3D distance of the centroid of the nine selected round perfusion-defective nodules. Gated SPET images were completed within 29 min, and increased the number of visible ventilation and perfusion defects by 9.7% and 17.2%, respectively, as compared with ungated images; furthermore, lesion-to-normal lung contrast was significantly higher on gated SPET images. In the nine round perfusion-defective nodules, gated images yielded a significantly better SPET-CT match compared with ungated images (4.9±3.1 mm vs 19.0±9.1 mm, P<0.001). The co-registered SPET-CT images allowed accurate perception of the location and extent of each ventilation/perfusion defect on the underlying CT anatomy, and characterised the pathophysiology of the various diseases. By reducing respiratory motion effects and enhancing perfusion/ventilation defect clarity, gated SPET can provide reliable co-registered images with CT images to accurately characterise regional functional impairment in various lung diseases. (orig.)

  16. Initial Egyptian ECMO experience

    Directory of Open Access Journals (Sweden)

    Akram Abdelbary

    2016-04-01

    Results: A total of twelve patients received ECMO between January 2014 and June 2015. The mean age was 35.9 years. (range 13–65 years, 8 males, with VV ECMO in 10 patients, and VA ECMO in 2 patients. Out of ten patients of VV ECMO, one had H1N1 pneumonia, one had advanced vasculitic lung, four had bacterial pneumonia, two traumatic lung contusions and one with organophosphorus poisoning, and one undiagnosed etiology leading to severe ARDS. Lung injury score range was 3–3.8, PaO2/FiO2 (20–76 mechanical ventilation duration before ECMO 1–14 days, Femoro-jugular cannulation in 7 patients and femoro-femoral in 2 patients and femoro-subclavian in 1 patient; all patients were initially sedated and paralyzed for (2–4 days and ventilated on pressure controlled ventilation with Pmax of 25 cm H2O and PEEP of 10 cm H2O. In VA ECMO patients were cannulated percutaneously using femoro-femoral approach. One patient showed no neurologic recovery and died after 24 h, the other had CABG on ECMO however the heart didn’t recover and died after 9 days. Heparin intravenous infusion was used initially in all patients and changed to Bivalirudin in 2 patients due to possible HIT. Pump flow ranged from 2.6 to 6.5 L/min. Average support time was 12 days (range 2–24 days. Seven patients (63.3% were successfully separated from ECMO and survived to hospital discharge. Hospital length of stay ranged from 3 to 42 days, tracheostomy was done percutaneously in 5 patients and surgically in 3. Gastrointestinal bleeding occurred in 6 patients, VAP in 7 patients, neurologic complications in 1 patient with complete recovery, cardiac arrhythmias in 3 patients, pneumothorax in 9 patients, and deep venous thrombosis in 2 patients.

  17. Evaluation of bone metastases with {sup 18} F- Sodium fluoride PET/CT; initial experience; Evaluacion de metastasis oseas con {sup 18} F-Fluoruro de sodio PET/CT; experiencia inicial

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez C, N.; Serna M, J.A.; Quiroz C, O.; Quinzanos, F.; Valenzuela, J.; Ramirez A, J.L. [Hospital Angeles del Pedregal, Mexico D.F. (Mexico)

    2007-07-01

    The study of NaF-18 PET/CT is the modality with bigger sensitivity and specificity for the bony metastases detection. This additional value of the NaF-18 PET/CT can have a beneficent impact in the clinical handling of the patients with prostate cancer with high risk. (Author)

  18. Initial clinical experience with dual-layer detector spectral CT in patients with acute intracerebral haemorrhage: A single-centre pilot study.

    Directory of Open Access Journals (Sweden)

    Soo Buem Cho

    Full Text Available The purpose of this study was to investigate the clinical feasibility of spectral analyses using dual-layer detector spectral computed tomography (CT in acute intracerebral haemorrhage (ICH.We retrospectively reviewed patients with acute ICH who underwent CT angiography on a dual-layer detector spectral CT scanner. A spectral data analysis was performed to detect contrast enhancement in or adjacent to acute ICH by using spectral image reconstructions including monoenergetic (MonoE, virtual noncontrast (VNC, and iodine overlay fusion images. We also acquired a spectral plot to assess material differentiation within lesions.Among the 30 patients, the most common cause of acute ICH was chronic hypertension (18/30, 60% followed by trauma (5/30, 16.7%, brain tumour (3/30, 10%, Moyamoya disease (2/30, 6.7%, and haemorrhagic diathesis from anticoagulation therapy (2/30, 6.7%. Of 30 patients, 13 showed suboptimal iodine suppression in the subcalvarial spaces on VNC images compared with true noncontrast images. The CT angiographic spot sign within the acute ICH was detected in four patients (4/30, 13.3%. All three tumours were metastatic and included lung cancer (n = 2 and hepatocellular carcinoma (n = 1 which showed conspicuous delineation of an enhancing tumour portion in the spectral analysis. Spectral analyses allowed the discrimination of acute haemorrhage and iodine with enhanced lesion visualization on the MonoE images obtained at lower keVs (less than 70 keV and spectral plot.Even though the image quality of VNC is perceived to be inferior, it is feasible to evaluate acute ICH in clinical settings using dual-layer detector spectral CT. The MonoE images taken at lower keVs were useful for depicting contrast enhancing lesion, and spectral plot might be helpful for material differentiation in patients with acute ICH.

  19. Initial clinical experience with dual-layer detector spectral CT in patients with acute intracerebral haemorrhage: A single-centre pilot study.

    Science.gov (United States)

    Cho, Soo Buem; Baek, Hye Jin; Ryu, Kyeong Hwa; Moon, Jin Il; Choi, Bo Hwa; Park, Sung Eun; Bae, Kyungsoo; Jeon, Kyung Nyeo; Kim, Dong Wook

    2017-01-01

    The purpose of this study was to investigate the clinical feasibility of spectral analyses using dual-layer detector spectral computed tomography (CT) in acute intracerebral haemorrhage (ICH). We retrospectively reviewed patients with acute ICH who underwent CT angiography on a dual-layer detector spectral CT scanner. A spectral data analysis was performed to detect contrast enhancement in or adjacent to acute ICH by using spectral image reconstructions including monoenergetic (MonoE), virtual noncontrast (VNC), and iodine overlay fusion images. We also acquired a spectral plot to assess material differentiation within lesions. Among the 30 patients, the most common cause of acute ICH was chronic hypertension (18/30, 60%) followed by trauma (5/30, 16.7%), brain tumour (3/30, 10%), Moyamoya disease (2/30, 6.7%), and haemorrhagic diathesis from anticoagulation therapy (2/30, 6.7%). Of 30 patients, 13 showed suboptimal iodine suppression in the subcalvarial spaces on VNC images compared with true noncontrast images. The CT angiographic spot sign within the acute ICH was detected in four patients (4/30, 13.3%). All three tumours were metastatic and included lung cancer (n = 2) and hepatocellular carcinoma (n = 1) which showed conspicuous delineation of an enhancing tumour portion in the spectral analysis. Spectral analyses allowed the discrimination of acute haemorrhage and iodine with enhanced lesion visualization on the MonoE images obtained at lower keVs (less than 70 keV) and spectral plot. Even though the image quality of VNC is perceived to be inferior, it is feasible to evaluate acute ICH in clinical settings using dual-layer detector spectral CT. The MonoE images taken at lower keVs were useful for depicting contrast enhancing lesion, and spectral plot might be helpful for material differentiation in patients with acute ICH.

  20. Coronary CT angiography: Comparison of a novel iterative reconstruction with filtered back projection for reconstruction of low-dose CT—Initial experience

    International Nuclear Information System (INIS)

    Takx, Richard A.P.; Schoepf, U. Joseph; Moscariello, Antonio; Das, Marco; Rowe, Garrett; Schoenberg, Stefan O.; Fink, Christian; Henzler, Thomas

    2013-01-01

    Objective: To prospectively compare subjective and objective image quality in 20% tube current coronary CT angiography (cCTA) datasets between an iterative reconstruction algorithm (SAFIRE) and traditional filtered back projection (FBP). Materials and methods: Twenty patients underwent a prospectively ECG-triggered dual-step cCTA protocol using 2nd generation dual-source CT (DSCT). CT raw data was reconstructed using standard FBP at full-dose (Group 1 a) and 80% tube current reduced low-dose (Group 1 b). The low-dose raw data was additionally reconstructed using iterative raw data reconstruction (Group 2 ). Attenuation and image noise were measured in three regions of interest and signal-to-noise-ratio (SNR) as well as contrast-to-noise-ratio (CNR) was calculated. Subjective diagnostic image quality was evaluated using a 4-point Likert scale. Results: Mean image noise of group 2 was lowered by 22% on average when compared to group 1 b (p 2 compared to group 1 b (p 2 (1.88 ± 0.63) was also rated significantly higher when compared to group 1 b (1.58 ± 0.63, p = 0.004). Conclusions: Image quality of 80% tube current reduced iteratively reconstructed cCTA raw data is significantly improved when compared to standard FBP and consequently may improve the diagnostic accuracy of cCTA

  1. Using cone-beam CT as a low-dose 3D imaging technique for the extremities: initial experience in 50 subjects

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Ambrose J.; Chang, Connie Y.; Palmer, William E. [Massachusetts General Hospital, Department of Radiology, Division of Musculoskeletal Imaging and Intervention, Boston, MA (United States); Thomas, Bijoy J. [Universal College of Medical Sciences, Department of Radiology, Bhairahawa (Nepal); MacMahon, Peter J. [Mater Misericordiae University Hospital, Department of Radiology, Dublin 7 (Ireland)

    2015-06-01

    To prospectively evaluate a dedicated extremity cone-beam CT (CBCT) scanner in cases with and without orthopedic hardware by (1) comparing its imaging duration and image quality to those of radiography and multidetector CT (MDCT) and (2) comparing its radiation dose to that of MDCT. Written informed consent was obtained for all subjects for this IRB-approved, HIPAA-compliant study. Fifty subjects with (1) fracture of small bones, (2) suspected intraarticular fracture, (3) fracture at the site of complex anatomy, or (4) a surgical site difficult to assess with radiography alone were recruited and scanned on an extremity CBCT scanner prior to FDA approval. Same-day radiographs were performed in all subjects. Some subjects also underwent MDCT within 1 month of CBCT. Imaging duration and image quality were compared between CBCT and radiographs. Imaging duration, effective radiation dose, and image quality were compared between CBCT and MDCT. Fifty-one CBCT scans were performed in 50 subjects. Average imaging duration was shorter for CBCT than radiographs (4.5 min vs. 6.6 min, P = 0.001, n = 51) and MDCT (7.6 min vs. 10.9 min, P = 0.01, n = 7). Average estimated effective radiation dose was less for CBCT than MDCT (0.04 mSv vs. 0.13 mSv, P = 0.02, n = 7). CBCT images yielded more diagnostic information than radiographs in 23/51 cases and more diagnostic information than MDCT in 1/7 cases, although radiographs were superior for detecting hardware complications. CBCT performs high-resolution imaging of the extremities using less imaging time than radiographs and MDCT and lower radiation dose than MDCT. (orig.)

  2. Feasibility of prospectively ECG-triggered high-pitch coronary CT angiography with 30 mL iodinated contrast agent at 70 kVp: initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Long Jiang; Qi, Li; Tang, Chun Xiang; Zhou, Chang Sheng; Ji, Xue Man; Lu, Guang Ming [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Wang, Jing [Medical School of Nanjing University, Department of Cardiology, Jinling Hospital, Nanjing, Jiangsu (China); Spearman, James V.; De Cecco, Carlo Nicola; Meinel, Felix G. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Schoepf, U.J. [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States)

    2014-07-15

    To evaluate the feasibility, image quality and radiation dose of prospectively ECG-triggered high-pitch coronary CT angiography (CCTA) with 30 mL contrast agent at 70 kVp. Fifty-eight patients with suspected coronary artery disease, a body mass index (BMI) of less than 25 kg/m{sup 2}, sinus rhythm and a heart rate (HR) of less than 70 beats per minute (bpm) were prospectively enrolled in this study. Thirty mL of 370 mg I/mL iodinated contrast agent was administrated at a flow rate of 5 mL/s. All patients underwent prospectively ECG-triggered high-pitch CCTA on a second-generation dual-source CT system at 70 kVp using automated tube current modulation. Fifty-six patients (96.6 %) had diagnostic CCTA images and two patients (3.4 %) had one vessel with poor image quality each rated as non-diagnostic. No significant effects of HR, HR variability and BMI on CCTA image quality were observed (all P > 0.05). Effective dose was 0.17 ± 0.02 mSv and the size-specific dose estimate was 1.03 ± 0.13 mGy. Prospectively ECG-triggered high-pitch CCTA at 70 kVp with 30 mL of contrast agent can provide diagnostic image quality at a radiation dose of less than 0.2 mSv in patients with a BMI of less than 25 kg/m{sup 2} and an HR of less than 70 bpm. (orig.)

  3. Using cone-beam CT as a low-dose 3D imaging technique for the extremities: initial experience in 50 subjects

    International Nuclear Information System (INIS)

    Huang, Ambrose J.; Chang, Connie Y.; Palmer, William E.; Thomas, Bijoy J.; MacMahon, Peter J.

    2015-01-01

    To prospectively evaluate a dedicated extremity cone-beam CT (CBCT) scanner in cases with and without orthopedic hardware by (1) comparing its imaging duration and image quality to those of radiography and multidetector CT (MDCT) and (2) comparing its radiation dose to that of MDCT. Written informed consent was obtained for all subjects for this IRB-approved, HIPAA-compliant study. Fifty subjects with (1) fracture of small bones, (2) suspected intraarticular fracture, (3) fracture at the site of complex anatomy, or (4) a surgical site difficult to assess with radiography alone were recruited and scanned on an extremity CBCT scanner prior to FDA approval. Same-day radiographs were performed in all subjects. Some subjects also underwent MDCT within 1 month of CBCT. Imaging duration and image quality were compared between CBCT and radiographs. Imaging duration, effective radiation dose, and image quality were compared between CBCT and MDCT. Fifty-one CBCT scans were performed in 50 subjects. Average imaging duration was shorter for CBCT than radiographs (4.5 min vs. 6.6 min, P = 0.001, n = 51) and MDCT (7.6 min vs. 10.9 min, P = 0.01, n = 7). Average estimated effective radiation dose was less for CBCT than MDCT (0.04 mSv vs. 0.13 mSv, P = 0.02, n = 7). CBCT images yielded more diagnostic information than radiographs in 23/51 cases and more diagnostic information than MDCT in 1/7 cases, although radiographs were superior for detecting hardware complications. CBCT performs high-resolution imaging of the extremities using less imaging time than radiographs and MDCT and lower radiation dose than MDCT. (orig.)

  4. EXPERIENCES WITH IDEA PROMOTING INITIATIVES

    DEFF Research Database (Denmark)

    Gish, Liv

    2011-01-01

    In new product development a central activity is to provide new ideas. Over the last decades experiences with stimulating employee creativity and establishing idea promoting initiatives have been made in industrial practice. Such initiatives are often labeled Idea Management – a research field...... with a growing interest. In this paper I examine three different idea promoting initiatives carried out in Grundfos, a leading pump manufacturer. In the analysis I address what understandings of idea work are inscribed in the initiatives and what role these initiatives play in the organization with respect...... understandings of idea work are inscribed in the idea promoting initiatives as they to some degree have to fit with the understandings embedded in practice in order to work....

  5. C-arm cone-beam CT combined with a new electromagnetic navigation system for guidance of percutaneous needle biopsies. Initial clinical experience

    International Nuclear Information System (INIS)

    Kickuth, R.; Reichling, C.; Bley, T.; Hahn, D.; Ritter, C.

    2015-01-01

    To evaluate the feasibility and efficacy of C-arm fluoroscopic cone-beam computed tomography (CACT) in combination with a new electromagnetic tracking (EMT) system for needle guidance during percutaneous biopsies. 53 patients were referred for biopsy of thoracic (n = 19) and abdominal (n = 34) lesions. CT-like images of the anatomical region of interest (ROI) were generated using a flat panel-based angiographic system. These images were transmitted to an EMT system. A coaxial puncture needle with a sensor in its tip was connected with the navigation system and tracked into an electromagnetic field created via a field generator. Data generated within this field were merged with the CACT images. On a monitor both the anatomical ROI and needle tip position were displayed to enable precise needle insertion into the target. Through the coaxial needle, biopsy specimens for the histologic evaluation were extracted. Number of representative biopsy samples, number of core biopsies/patient, total procedure time, dose-area product, fluoroscopic time, and complications were recorded. 53 CACT/EMT-guided biopsy procedures were performed, 48 of which (91 %) yielded representative tissue samples. Four core biopsies were obtained from each patient. 40 (75 %) lesions were malignant and 13 (25 %) lesions were benign. The total procedure time was 9 ± 5 min (range, 3 - 23 min), fluoroscopic time was 0.8 ± 0.4 min (range, 0.4 - 2 min). The mean dose-area product (cGy cm 2 ) was 7373 (range, 895 - 26 904). The rate of complications (1 pneumothorax, 2 hemoptyses) was 6 %. CACT combined with EMT appears to be a feasible and effective technique for the guidance of percutaneous biopsies with a low rate of therapeutically relevant complications.

  6. C-arm cone-beam CT combined with a new electromagnetic navigation system for guidance of percutaneous needle biopsies. Initial clinical experience

    Energy Technology Data Exchange (ETDEWEB)

    Kickuth, R.; Reichling, C.; Bley, T.; Hahn, D.; Ritter, C. [University Hospital of Wuerzburg (Germany). Inst. of Diagnostic and Interventional Radiology

    2015-07-15

    To evaluate the feasibility and efficacy of C-arm fluoroscopic cone-beam computed tomography (CACT) in combination with a new electromagnetic tracking (EMT) system for needle guidance during percutaneous biopsies. 53 patients were referred for biopsy of thoracic (n = 19) and abdominal (n = 34) lesions. CT-like images of the anatomical region of interest (ROI) were generated using a flat panel-based angiographic system. These images were transmitted to an EMT system. A coaxial puncture needle with a sensor in its tip was connected with the navigation system and tracked into an electromagnetic field created via a field generator. Data generated within this field were merged with the CACT images. On a monitor both the anatomical ROI and needle tip position were displayed to enable precise needle insertion into the target. Through the coaxial needle, biopsy specimens for the histologic evaluation were extracted. Number of representative biopsy samples, number of core biopsies/patient, total procedure time, dose-area product, fluoroscopic time, and complications were recorded. 53 CACT/EMT-guided biopsy procedures were performed, 48 of which (91 %) yielded representative tissue samples. Four core biopsies were obtained from each patient. 40 (75 %) lesions were malignant and 13 (25 %) lesions were benign. The total procedure time was 9 ± 5 min (range, 3 - 23 min), fluoroscopic time was 0.8 ± 0.4 min (range, 0.4 - 2 min). The mean dose-area product (cGy cm{sup 2}) was 7373 (range, 895 - 26 904). The rate of complications (1 pneumothorax, 2 hemoptyses) was 6 %. CACT combined with EMT appears to be a feasible and effective technique for the guidance of percutaneous biopsies with a low rate of therapeutically relevant complications.

  7. Initial experience with prospectively triggered, sequential CT coronary angiography on a 128-slice scanner; Erste Erfahrungen mit der sequenziellen, prospektiv getriggerten CT-Koronarangiografie an einem 128-Schicht-Computertomografen

    Energy Technology Data Exchange (ETDEWEB)

    Anders, K.; Baum, U.; Kuefner, M.A.; Kuettner, A.; Uder, M. [Universitaetsklinikum Erlangen (Germany). Radiologisches Inst.; Gauss, S.; Achenbach, S.; Daniel, W.G.; Ropers, D. [Universitaetsklinikum Erlangen (Germany). Medizinische Klinik 2

    2009-04-15

    Purpose: Spiral CT angiography (CTA) of the coronaries using low-pitch scanning and ECG-gated image reconstruction is a robust method for detecting or excluding relevant coronary plaque. However, the resulting dose exposure is considerable. The aim of the present study was to evaluate image quality and artifacts as well as to record dose values for sequential coronary CTA using a 128-slice scanner with a temporal resolution of 150 ms. Materials und Methods: 20 patients with a regular heart rate and without contraindications for oral/I.V. beta blockers, who were referred for CTA of the coronaries for exclusion or detection of relevant plaques, were examined by sequential CTA with the following parameters: 120 kV, 200 ref mAs, collimation 2 x 64 x 0.6, table feed of 34.5 mm at a detector width of 38.4 mm. A total acquisition time of 380 ms per table position allowed for mild shifting of the reconstruction window within the cardiac cycle of {+-} 5 %. 50 ml of contrast agent were injected at 5 ml/s followed by a 50 ml split bolus (20 % contrast). The individual start delay was determined by a test bolus scan (10 ml contrast + 50 ml saline flush at 5 ml/s). The image quality for each segment, coronary artery, and patient was determined on a 4-point scale. Dose values were estimated based on the individual dose length product as provided by the scanner's patient protocol. Artifacts were evaluated to determine the cause (calcium vs. motion). Results: All patients received beta blocker pretreatment. The mean heart rate was 62 {+-} 5 beats/min. 5 % (13/286) of all segments in 5/20 patients were rated as non-diagnostic. The mean dose length product was 213 mGy x cm, and the mean effective dose was 3.6 mSv. Calcifications were the major cause of non-diagnostic images. However breathing or other motion artifacts occurred as well. (orig.)

  8. PET CT imaging: the Philippine experience

    International Nuclear Information System (INIS)

    Santiago, Jonas Y.

    2011-01-01

    Currently, the most discussed fusion imaging is PET CT. Fusion technology has tremendous potential in diagnostic imaging to detect numerous conditions such as tumors, Alzheimer's disease, dementia and neural disorders. The fusion of PET with CT helps in the localization of molecular abnormalities, thereby increasing diagnostic accuracy and differentiating benign or artefact lesions from malignant diseases. It uses a radiotracer called fluro deoxyglucose that gives a clear distinction between pathological and physiological uptake. Interest in this technology is increasing and additional clinical validation are likely to induce more health care providers to invest in combined scanners. It is hope that in time, a better appreciation of its advantages over conventional and traditional imaging modalities will be realized. The first PET CT facility in the country was established at the St. Luke's Medical Center in Quezon City in 2008 and has since then provided a state-of-the art imaging modality to its patients here and those from other countries. The paper will present the experiences so far gained from its operation, including the measures and steps currently taken by the facility to ensure optimum workers and patient safety. Plans and programs to further enhance the awareness of the Filipino public on this advanced imaging modality for an improved health care delivery system may also be discussed briefly. (author)

  9. Imaging CT findings in cases of subdural hematoma after cardiovascular surgery. Initial signs of SDH

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Michiyuki; Kuriyama, Yoshihiro; Sawada, Tohru; Ogawa, Makoto; Kaneko, Takaji; Sakamoto, Akira; Kawazoe, Kouhei; Fujita, Tsuyoshi; Omae, Teruo

    1987-12-01

    A characteristic initial sign of CT findings, as seen in cases of subdural hematoma (SDH) after cardiovascular surgery, was reported. Central-nervous-system (CNS) complications after cardiovascular surgery have been thought to be due mainly to the ischemic brain damage caused by both reduced cerebral perfusion pressure and microembolism during extracorporeal circulation. However, we observed 8 cases of SDH in 39 patients suffering from major CNS complications after cardiovascular surgery. In view of these experiences, SDH was thought to be one of the most significant factors causing CNS complications after cardiovascular surgery. In the sequential CT scans of 8 cases of SDH, four exhibited a typical, small, spotty high-density area in the early period of SDH. The clinical courses of these four patients were relatively acute or subacute, and the initial small high-density area progressed to definite SDH findings in that region in the follow-up CT. These initial findings of CT scans were regarded as ''initial signs of SDH-ISS-''. Although there have been many reports concerning the sequential CT changes in SDH, there has been no report describing the above-mentioned finding. It was emphasized that ''ISS'' is of great importance in the early management for SDH.

  10. Experiments on CT plasma merging in the CTCC-1

    International Nuclear Information System (INIS)

    Watanabe, K.; Ikegami, K.; Nishikawa, M.; Ozaki, A.; Satomi, N.; Uyama, T.

    1982-01-01

    A compact toroid (CT) plasma merging experiment has been tried preliminarily in the CTCC-1 experiment as a method for further-heating of CT, on producing two CT plasmas in the flux conserver successively. Two CT plasmas were observed really to merge with each other in the flux conserver. In the merging process, it is found that the field reconnection of surface magnetic field lines of CT is completed until 30 μs after the second CT injection, but magnetic field lines around the center of CT merge slowly, taking about 100 μs. Experimental results indicate that merging of CT results in doubled addition of toroidal fluxes and no-addition of poloidal fluxes

  11. Energy efficiency initiatives: Indian experience

    Energy Technology Data Exchange (ETDEWEB)

    Dey, Dipankar [ICFAI Business School, Kolkata, (IBS-K) (India)

    2007-07-01

    India, with a population of over 1.10 billion is one of the fastest growing economies of the world. As domestic sources of different conventional commercial energy are drying up, dependence on foreign energy sources is increasing. There exists a huge potential for saving energy in India. After the first 'oil shock' (1973), the government of India realized the need for conservation of energy and a 'Petroleum Conservation Action Group' was formed in 1976. Since then many initiatives aiming at energy conservation and improving energy efficiency, have been undertaken (the establishment of Petroleum Conservation Research Association in 1978; the notification of Eco labelling scheme in 1991; the formation of Bureau of Energy Efficiency in 2002). But no such initiative was successful. In this paper an attempt has been made to analyze the changing importance of energy conservation/efficiency measures which have been initiated in India between 1970 and 2005.The present study tries to analyze the limitations and the reasons of failure of those initiatives. The probable reasons are: fuel pricing mechanism (including subsidies), political factors, corruption and unethical practices, influence of oil and related industry lobbies - both internal and external, the economic situation and the prolonged protection of domestic industries. Further, as India is opening its economy, the study explores the opportunities that the globally competitive market would offer to improve the overall energy efficiency of the economy. The study suggests that the Bureau of Energy Efficiency (BEE) - the newly formed nodal agency for improving energy efficiency of the economy may be made an autonomous institution where intervention from the politicians would be very low. For proper implementation of different initiatives to improve energy efficiency, BEE should involve more the civil societies (NGO) from the inception to the implementation stage of the programs. The paper also

  12. Metabolic and clinical assessment of efficacy of cryoablation therapy on skeletal masses by 18F-FDG positron emission tomography/computed tomography (PET/CT) and visual analogue scale (VAS): initial experience

    International Nuclear Information System (INIS)

    Masala, Salvatore; Bartolucci, Alberto D.; Mammucari, Matteo; Simonetti, Giovanni; Schillaci, Orazio; Calabria, Ferdinando

    2011-01-01

    Various therapy modalities have been proposed as standard treatments in management of bone metastases. Radiation therapy remains the standard of care for patients with localized bone pain, but up to 30% of them do not experience notable pain relief. Percutaneous cryoablation is a minimally invasive technique that induces necrosis by alternately freezing and thawing a target tissue. This technique is successfully used to treat a variety of malignant and benign diseases in different sites. 18 F-FDG positron emission tomography/computed tomography ( 18 F-FDG PET/CT) is a single technique of imaging that provides in a ''single step'' both morphological and metabolic features of neoplastic lesions of the bone. The aim of this study was to evaluate the efficacy of the cryosurgical technique on secondary musculoskeletal masses according to semi-quantitative PET analysis and clinical-test evaluation with the visual analogue scale (VAS). We enrolled 20 patients with painful bone lesions (score pain that exceeded 4 on the VAS) that were non-responsive to treatment; one lesion per patient was treated. All patients underwent a PET-CT evaluation before and 8 weeks after cryotherapy; maximum standardized uptake value (SUV max ) was measured before and after treatment for metabolic assessment of response to therapy. After treatment, 18 patients (90%) showed considerable reduction in SUV max value (>50%) suggestive of response to treatment; only 2 patients did not show meaningful reduction in metabolic activity. Our preliminary study demonstrates that quantitative analysis provided by PET correlates with response to cryoablation therapy as assessed by CT data and clinical VAS evaluation. (orig.)

  13. Metabolic and clinical assessment of efficacy of cryoablation therapy on skeletal masses by {sup 18}F-FDG positron emission tomography/computed tomography (PET/CT) and visual analogue scale (VAS): initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Masala, Salvatore; Bartolucci, Alberto D.; Mammucari, Matteo; Simonetti, Giovanni [University Hospital Tor Vergata, Department of Diagnostic and Molecular Imaging, Interventional Radiology and Radiotherapy, Rome (Italy); Schillaci, Orazio; Calabria, Ferdinando [University Hospital Tor Vergata, Department of Diagnostic and Molecular Imaging, Interventional Radiology and Radiotherapy, Rome (Italy); I.R.C.C.S. Neuromed, Department of Nuclear Medicine and Neuroradiology, Pozzilli (Italy); Policlinico Tor Vegata, Department of Diagnostic and Molecular Imaging, Interventional Radiology and Radiotherapy, Rome (Italy)

    2011-02-15

    Various therapy modalities have been proposed as standard treatments in management of bone metastases. Radiation therapy remains the standard of care for patients with localized bone pain, but up to 30% of them do not experience notable pain relief. Percutaneous cryoablation is a minimally invasive technique that induces necrosis by alternately freezing and thawing a target tissue. This technique is successfully used to treat a variety of malignant and benign diseases in different sites. {sup 18}F-FDG positron emission tomography/computed tomography ({sup 18}F-FDG PET/CT) is a single technique of imaging that provides in a ''single step'' both morphological and metabolic features of neoplastic lesions of the bone. The aim of this study was to evaluate the efficacy of the cryosurgical technique on secondary musculoskeletal masses according to semi-quantitative PET analysis and clinical-test evaluation with the visual analogue scale (VAS). We enrolled 20 patients with painful bone lesions (score pain that exceeded 4 on the VAS) that were non-responsive to treatment; one lesion per patient was treated. All patients underwent a PET-CT evaluation before and 8 weeks after cryotherapy; maximum standardized uptake value (SUV{sub max}) was measured before and after treatment for metabolic assessment of response to therapy. After treatment, 18 patients (90%) showed considerable reduction in SUV{sub max} value (>50%) suggestive of response to treatment; only 2 patients did not show meaningful reduction in metabolic activity. Our preliminary study demonstrates that quantitative analysis provided by PET correlates with response to cryoablation therapy as assessed by CT data and clinical VAS evaluation. (orig.)

  14. Evaluation of abdominal CT in the initial treatment of abdominal trauma

    International Nuclear Information System (INIS)

    Watanabe, Shinsuke; Ishii, Takashi; Kuwata, Katsuya; Yoneyama, Chihiro; Kitamura, Kazuya; Sasaki, Yoshifumi; Kamachi, Masahiro; Nishiguchi, Hiroyasu.

    1986-01-01

    During the last four years 102 patients with abdominal trauma were examined by CT for preoperative evaluation in our hospital. In 35 patients (34 %), the CT scans revealed no abnormal findings. They were all managed conservatively except for one case of perforated small bowel. In 67 patients (66 %) CT revealed evidences of substantial abdominal or retroperitoneal trauma. In 30 of them CT findings were confirmed by surgery. Hepatic injury is usually easily recognized by CT. CT is also useful for the detection of renal or splenic injuries. The majority of those parenchymatous organ injuries were successfully managed with conservative therapy, despite apparent traumatic lesions revealed by CT. Repeat CT scans is proved to be very useful to follow the changes of these traumatic lesions. In conclusion, application of abdominal CT is extremely useful for the initial decision making in treatment of patients with abdominal trauma and for the follow-up observation of injured lesions. (author)

  15. A benchmark on computational simulation of a CT fracture experiment

    International Nuclear Information System (INIS)

    Franco, C.; Brochard, J.; Ignaccolo, S.; Eripret, C.

    1992-01-01

    For a better understanding of the fracture behavior of cracked welds in piping, FRAMATOME, EDF and CEA have launched an important analytical research program. This program is mainly based on the analysis of the effects of the geometrical parameters (the crack size and the welded joint dimensions) and the yield strength ratio on the fracture behavior of several cracked configurations. Two approaches have been selected for the fracture analyses: on one hand, the global approach based on the concept of crack driving force J and on the other hand, a local approach of ductile fracture. In this approach the crack initiation and growth are modelized by the nucleation, growth and coalescence of cavities in front of the crack tip. The model selected in this study estimates only the growth of the cavities using the RICE and TRACEY relationship. The present study deals with a benchmark on computational simulation of CT fracture experiments using three computer codes : ALIBABA developed by EDF the CEA's code CASTEM 2000 and the FRAMATOME's code SYSTUS. The paper is split into three parts. At first, the authors present the experimental procedure for high temperature toughness testing of two CT specimens taken from a welded pipe, characteristic of pressurized water reactor primary piping. Secondly, considerations are outlined about the Finite Element analysis and the application procedure. A detailed description is given on boundary and loading conditions, on the mesh characteristics, on the numerical scheme involved and on the void growth computation. Finally, the comparisons between numerical and experimental results are presented up to the crack initiation, the tearing process being not taken into account in the present study. The variations of J and of the local variables used to estimate the damage around the crack tip (triaxiality and hydrostatic stresses, plastic deformations, void growth ...) are computed as a function of the increasing load

  16. Initial investigation into lower-cost CT for resource limited regions of the world

    Science.gov (United States)

    Dobbins, James T., III; Wells, Jered R.; Segars, W. Paul; Li, Christina M.; Kigongo, Christopher J. N.

    2010-04-01

    This paper describes an initial investigation into means for producing lower-cost CT scanners for resource limited regions of the world. In regions such as sub-Saharan Africa, intermediate level medical facilities serving millions have no CT machines, and lack the imaging resources necessary to determine whether certain patients would benefit from being transferred to a hospital in a larger city for further diagnostic workup or treatment. Low-cost CT scanners would potentially be of immense help to the healthcare system in such regions. Such scanners would not produce state-of-theart image quality, but rather would be intended primarily for triaging purposes to determine the patients who would benefit from transfer to larger hospitals. The lower-cost scanner investigated here consists of a fixed digital radiography system and a rotating patient stage. This paper describes initial experiments to determine if such a configuration is feasible. Experiments were conducted using (1) x-ray image acquisition, a physical anthropomorphic chest phantom, and a flat-panel detector system, and (2) a computer-simulated XCAT chest phantom. Both the physical phantom and simulated phantom produced excellent image quality reconstructions when the phantom was perfectly aligned during acquisition, but artifacts were noted when the phantom was displaced to simulate patient motion. An algorithm was developed to correct for motion of the phantom and demonstrated success in correcting for 5-mm motion during 360-degree acquisition of images. These experiments demonstrated feasibility for this approach, but additional work is required to determine the exact limitations produced by patient motion.

  17. Initial staging of Hodgkin's disease: role of contrast-enhanced 18F FDG PET/CT.

    Science.gov (United States)

    Chiaravalloti, Agostino; Danieli, Roberta; Caracciolo, Cristiana Ragano; Travascio, Laura; Cantonetti, Maria; Gallamini, Andrea; Guazzaroni, Manlio; Orlacchio, Antonio; Simonetti, Giovanni; Schillaci, Orazio

    2014-08-01

    The objective of this study was to compare the diagnostic accuracy of positron emission tomography/low-dose computed tomography (PET/ldCT) versus the same technique implemented by contrast-enhanced computed tomography (ceCT) in staging Hodgkin's disease (HD).Forty patients (18 men and 22 women, mean age 30 ± 9.6) with biopsy-proven HD underwent a PET/ldCT study for initial staging including an unenhanced low-dose computed tomography for attenuation correction with positron emission tomography acquisition and a ceCT, performed at the end of the PET/ldCT scan, in the same exam session. A detailed datasheet was generated for illness locations for separate imaging modality comparison and then merged in order to compare the separate imaging method results (PET/ldCT and ceCT) versus merged results positron emission tomography/contrast-enhanced computed tomography (PET/ceCT). The nodal and extranodal lesions detected by each technique were then compared with follow-up data that served as the reference standard.No significant differences were found at staging between PET/ldCT and PET/ceCT in our series. One hundred and eighty four stations of nodal involvement have been found with no differences in both modalities. Extranodal involvement was identified in 26 sites by PET/ldCT and in 28 by PET/ceCT. We did not find significant differences concerning the stage (Ann Arbor).Our study shows a good concordance and conjunction between PET/ldCT and ceCT in both nodal and extranodal sites in the initial staging of HD, suggesting that PET/ldCT could suffice in most of these patients.

  18. How to choose PET-CT or CT in the diagnosis and staging of lung cancer. Practical experience in China

    International Nuclear Information System (INIS)

    Jiang, T.; Tao, X.; Liu, H.; Liu, S.; Zheng, X.

    2010-01-01

    How to use CT and PET-CT rationally to raise diagnosis, staging and prognostic assessment of lung cancer to a higher level at the best cost-effect ratio is a subject that Chinese clinicians and radiologists should face conscientiously. We review the rational application of CT and PET-CT in four aspects of lung cancer, including screening and detection, morphologic evaluation, haemodynamic or metabolic feature evaluation, and follow-up, staging and prognostic evaluation. As PET-CT is only available in class III-A hospitals today, CT is the most popular equipment in China. PET-CT is more valuable only in cases where CT presentation of lung cancer is atypical or difficult to determine, or in cases where the diagnosis of lung cancer has been initially confirmed, for which clinical staging and decision concerning on therapeutic regimens are needed. We also recommend the current strategies of CT and PET-CT managing of SPN in China. (orig.)

  19. Comparison of PET/CT and PET/MRI hybrid systems using a {sup 68}Ga-labelled PSMA ligand for the diagnosis of recurrent prostate cancer: initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Afshar-Oromieh, A. [University Hospital Heidelberg, Department of Nuclear Medicine, Heidelberg (Germany); German Cancer Research Center (DKFZ), Department of Radiology, Heidelberg (Germany); Haberkorn, U. [University Hospital Heidelberg, Department of Nuclear Medicine, Heidelberg (Germany); German Cancer Research Center (DKFZ), Clinical Cooperation Unit of Nuclear Medicine, Heidelberg (Germany); Schlemmer, H.P.; Fenchel, M.; Roethke, M. [German Cancer Research Center (DKFZ), Department of Radiology, Heidelberg (Germany); Eder, M.; Eisenhut, M. [German Cancer Research Center (DKFZ), Department of Radiopharmaceutical Chemistry, Heidelberg (Germany); Hadaschik, B.A. [University Hospital Heidelberg, Department of Urology, Heidelberg (Germany); Kopp-Schneider, A. [German Cancer Research Center (DKFZ), Department of Biostatistics, Heidelberg (Germany)

    2014-05-15

    {sup 68}Ga-labelled HBED-CC-PSMA is a highly promising tracer for imaging recurrent prostate cancer (PCa). The intention of this study was to evaluate the feasibility of PET/MRI with this tracer. Twenty patients underwent PET/CT 1 h after injection of the {sup 68}Ga-PSMA ligand followed by PET/MRI 3 h after injection. Data from the two investigations were first analysed separately and then compared with respect to tumour detection rate and radiotracer uptake in various tissues. To evaluate the quantification accuracy of the PET/MRI system, differences in SUVs between PET/CT and corresponding PET/MRI were compared with differences in SUVs between PET/CT 1 h and 3 h after injection in another patient cohort. This cohort was investigated using the same PET/CT system. With PET/MRI, different diagnostic sequences, higher contrast of lesions and higher resolution of MRI enabled a subjectively easier evaluation of the images. In addition, four unclear findings on PET/CT could be clarified as characteristic of PCa metastases by PET/MRI. However, in PET images of the PET/MRI, a reduced signal was observed at the level of the kidneys (in 11 patients) and around the urinary bladder (in 15 patients). This led to reduced SUVs in six lesions. SUV{sub mean} values provided by the PET/MRI system were different in muscles, blood pool, liver and spleen. PCa was detected more easily and more accurately with Ga-PSMA PET/MRI than with PET/CT and with lower radiation exposure. Consequently, this new technique could clarify unclear findings on PET/CT. However, scatter correction was challenging when the specific {sup 68}Ga-PSMA ligand was used. Moreover, direct comparison of SUVs from PET/CT and PET/MR needs to be conducted carefully. (orig.)

  20. Return to Experience and Initial Wage Level

    DEFF Research Database (Denmark)

    Sørensen, Kenneth Lykke; Vejlin, Rune Majlund

    This paper estimates the relationship between initial wage and return to experience. We use a Mincer-like wage model to nonparametrically estimate this relationship allowing for an unobservable individual permanent effect in wages and unobservable individual return to experience. The relationship...

  1. Return to experience and initial wage level

    DEFF Research Database (Denmark)

    Sørensen, K.L.; Vejlin, R.

    2014-01-01

    This paper estimates the relationship between initial wage and return to experience. We use a Mincer-like wage model to non-parametrically estimate this relationship allowing for an unobservable individual permanent effect in wages and unobservable individual return to experience. The relationshi...

  2. Initial conditions of radiative shock experiments

    International Nuclear Information System (INIS)

    Kuranz, C. C.; Drake, R. P.; Krauland, C. M.; Marion, D. C.; Grosskopf, M. J.; Rutter, E.; Torralva, B.; Holloway, J. P.; Bingham, D.; Goh, J.; Boehly, T. R.; Sorce, A. T.

    2013-01-01

    We performed experiments at the Omega Laser Facility to characterize the initial, laser-driven state of a radiative shock experiment. These experiments aimed to measure the shock breakout time from a thin, laser-irradiated Be disk. The data are then used to inform a range of valid model parameters, such as electron flux limiter and polytropic γ, used when simulating radiative shock experiments using radiation hydrodynamics codes. The characterization experiment and the radiative shock experiment use a laser irradiance of ∼7 × 10 14 W cm −2 to launch a shock in the Be disk. A velocity interferometer and a streaked optical pyrometer were used to infer the amount of time for the shock to move through the Be disk. The experimental results were compared with simulation results from the Hyades code, which can be used to model the initial conditions of a radiative shock system using the CRASH code

  3. Serial high resolution CT in non-specific interstitial pneumonia: prognostic value of the initial pattern

    Energy Technology Data Exchange (ETDEWEB)

    Screaton, N.J. [Department of Radiology, Addenbrooke' s Hospital, Cambridge (United Kingdom)]. E-mail: nicholas.screaton@papworth.nhs.uk; Hiorns, M.P. [Department of Radiology, Great Ormond Street Hospital, London (United Kingdom); Lee, K.S. [Samsung Medical Centre, Seoul (Korea); Franquet, T. [Hospital de Saint Pau, Universidad Autonoma de Barcelona, Barcelona (Spain); Johkoh, T. [Department of Medical Physics and Radiology, Osaka University Graduate School of Medicine, Osaka (Japan); Fujimoto, K. [Department of Radiology, Kurume University School of Medicine, Kurume (Japan); Ichikado, K. [First Department of Internal Medicine, Kumamoto University School of Medicine, Kumamoto (Japan); Colby, T.V. [Department of Laboratory Medicine/Pathology, Mayo Clinic Scottsdale, AZ (United States); Mueller, N.L. [Department of Radiology, Vancouver General Hospital, Vancouver (Canada)

    2005-01-01

    AIM: To assess the relationship between initial CT pattern and serial changes in CT findings and pulmonary function tests (PFTs) in patients with non-specific interstitial pneumonia (NSIP). MATERIALS AND METHODS: Serial high resolution (HR) CTs and PFTs were retrospectively analyzed in 38 cases of histologically proven NSIP, including 4 with cellular NSIP, 13 with mixed cellular and fibrotic NSIP, and 21 with fibrotic NSIP. The presence and extent of various CT findings were assessed. A fibrosis index (defined as the ratio of the extent of a reticular/honeycomb pattern to the overall extent of abnormal parenchyma) was derived. RESULTS: The predominant CT pattern was reticular/honeycomb in 27 (84%) cases and ground-glass/consolidation in 6 (16%) cases. Between scans, mean disease extent reduced by 5.2%. Disease extent reduced by >10% in 13 (34%) and increased by >10% in 6 (16%) patients. Histopathological subtype of NSIP did not correlate with individual CT pattern, predominant pattern, fibrosis index or serial change in disease extent on CT or PFTs. Response on follow-up CT was associated with fibrosis index, predominant pattern and extent of consolidation on initial CT. CONCLUSION: In NSIP disease, progression on CT correlates with the predominant CT pattern, fibrosis index, and extent of consolidation but not with histopathological subtype. An inflammatory (ground-glass/consolidation) predominant pattern is associated with better outcome in terms of disease extent on HRCT.

  4. CT colonography: effect of experience and training on reader performance

    International Nuclear Information System (INIS)

    Taylor, Stuart A.; Burling, David; Morley, Simon; Bartram, Clive I.; Halligan, Steve; Bassett, Paul; Atkin, Wendy

    2004-01-01

    The purpose of this paper was to investigate the effect of radiologist experience and increasing exposure to CT colonography on reader performance. Three radiologists of differing general experience (consultant, research fellow, trainee) independently analysed 100 CT colonographic datasets. Readers had no prior experience of CT colonography and received feedback and training after the first 50 cases from an independent experienced radiologist. Diagnostic performance and reporting times were compared for the first and second 50 datasets and compared with the results of a radiologist experienced in CT colonography. Before training only the consultant reader achieved statistical equivalence with the reference standard for detection of larger polyps. After training, detection rates ranged between 25 and 58% for larger polyps. Only the trainee significantly improved after training (P=0.007), with performance of other readers unchanged or even worse. Reporting times following training were reduced significantly for the consultant and fellow (P<0.001 and P=0.03, respectively), but increased for the trainee (P<0.001). In comparison to the consultant reader, the odds of detection of larger polyps was 0.36 (CI 0.16, 0.82) for the fellow and 0.36 (CI 0.14, 0.91) for the trainee. There is considerable variation in the ability to report CT colonography. Prior experience in gastrointestinal radiology is a distinct advantage. Competence cannot be assumed even after directed training via a database of 50 cases. (orig.)

  5. Ultra-high pitch chest computed tomography at 70 kVp tube voltage in an anthropomorphic pediatric phantom and non-sedated pediatric patients: Initial experience with 3rd generation dual-source CT.

    Science.gov (United States)

    Hagelstein, Claudia; Henzler, Thomas; Haubenreisser, Holger; Meyer, Mathias; Sudarski, Sonja; Schoenberg, Stefan O; Neff, K Wolfgang; Weis, Meike

    2016-12-01

    Minimizing radiation dose while at the same time preserving image quality is of particular importance in pediatric chest CT. Very recently, CT imaging with a tube voltage of 70 kVp has become clinically available. However, image noise is inversely proportional to the tube voltage. We aimed to investigate radiation dose and image quality of pediatric chest CT performed at 70 kVp in an anthropomorphic pediatric phantom as well as in clinical patients. An anthropomorphic pediatric phantom, which resembles a one-year-old child in physiognomy, was scanned on the 3 rd generation dual-source CT (DSCT) system at 70 kVp and 80 kVp and a fixed ultra low tube-current of 8 mAs to solely evaluate the impact of lowering tube voltage. After the phantom measurements, 18 pediatric patients (mean 29.5 months; range 1-91 months; 21 examinations) underwent 3.2 high-pitch chest CT on the same DSCT system at 70 kVp tube voltage without any sedation. Radiation dose and presence of motion artifacts was compared to a retrospectively identified patient cohort examined at 80 kVp on a 16-slice single-source-CT (SSCT; n=15; 14/15 with sedation; mean 30.7 months; range 0-96 months; pitch=1.5) or on a 2 nd generation DSCT without any sedation (n=6; mean 32.8 months; range 4-61 months; pitch=3.2). Radiation dose in the phantom scans was reduced by approximately 40% when using a tube voltage of 70 kVp instead of 80 kVp. In the pediatric patient group examined at 70 kVp age-specific effective dose (ED; mean 0.5±0.2 mSv) was significantly lower when compared to the retrospective cohort scanned at 80 kVp on the 16-slice-SSCT (mean ED: 1.0±0.3 mSv; pCT examinations showed any motion artifacts whereas 13/15 examinations of the retrospective patient cohort scanned at 80 kVp with a pitch of 1.5 showed motion artifacts. 3.2 high-pitch chest CT performed with 70 kVp significantly reduces radiation dose when compared to 80 kVp while at the same time provides good image quality without any motion artifacts

  6. PET/CT-guided interventional procedures: rationale, justification, initial study, and research plan

    Energy Technology Data Exchange (ETDEWEB)

    Wong, K.; Rahill, J.; Cleary, K. [Computer Aided Interventions and Medical Robotics (CAIMR), Imaging Science and Information Systems (ISIS) Center, Georgetown Univ. Medical Center, Washington, DC (United States); Petrillo, S.; Earl-Graef, D. [Dept. of Radiology, Georgetown Univ. Hospital, MedStar Health, Washington, DC (United States); Banovac, F.; Levy, E. [Computer Aided Interventions and Medical Robotics (CAIMR), Imaging Science and Information Systems (ISIS) Center, Georgetown Univ. Medical Center, Washington, DC (United States); Dept. of Radiology, Georgetown Univ. Hospital, MedStar Health, Washington, DC (United States); Shekhar, R. [Dept. of Radiology, Univ. of Maryland Medical Center, Baltimore, MD (United States)

    2007-06-15

    Positron-emission tomography (PET) and PET/CT (computed tomography) are becoming increasingly important for diagnosis and treatment of cancer. Clinically relevant changes can sometimes be seen on PET that are not seen on other imaging modalities. However, PET is not suitable for guiding biopsy as the images are not obtained in real-time. Therefore, our research group has begun developing a concept for PET/CT-guided interventional procedures. This paper presents the rationale for this concept, outlines our research plan, and includes an initial study to evaluate the relative sensitivity of CT and PET/CT in detecting suspicious lesions. (orig.)

  7. FDG PET/CT in initial staging and early response to chemotherapy assessment of paediatric rhabdomyosarcomas

    International Nuclear Information System (INIS)

    Eugene, T.; Ansquer, C.; Oudoux, A.; Carlier, T.; Kraeber-Bodere, T.; Bodet-Milin, C.; Corradini, N.; Thomas, C.; Dupas, B.

    2010-01-01

    Purpose: The objective of this study was to retrospectively evaluate the impact of positron emission tomography/computed tomography (PET/CT) using fluorine-18-fluorodeoxyglucose (FDG), in comparison with conventional imaging modalities (CIM), for initial staging and early therapy assessment in paediatric rhabdomyosarcoma. Patients and methods: Prior to treatment, 18 patients (age range, 9 months to 18 years) with histologically proven rhabdomyosarcoma underwent FDG PET/CT in addition to CIM (magnetic resonance imaging of primary site, whole body CT and bone scintigraphy). After three courses of chemotherapy, 12 patients underwent FDG PET/CT in addition to CIM. RECIST criteria and visual analysis of FDG uptake were used for assessment of response. The standard of reference was determined by an interdisciplinary tumor board based on imaging material, histopathology and follow-up data (median = 5 years). Results: PET/CT sensitivity was superior to CIM's concerning lymph node involvement (100% versus 83%, respectively) and metastases detection (100% versus 50%, respectively). PET/CT results changed therapeutic management in 11% of cases. After three courses of chemotherapy, the rate of complete response was 66% with PET/CT versus 8% with CIM. Five percent of patients relapsed during follow-up (median = 5 years). Conclusion: This study confirms that PET/CT depicts important additional information in initial staging of paediatric rhabdomyosarcomas and suggests a superior prognostic value of PET/CT in early response to chemotherapy assessment. (authors)

  8. Initial observations of electronic medical record usage during CT and MRI interpretation: Frequency of use and impact on workflow.

    Science.gov (United States)

    Lin, Abraham; Harris, Mitchell; Zalis, Michael

    2010-07-01

    Electronic medical record (EMR) systems permit integration of contextual nonimaging EMR data into examination interpretation; however, the extra effort required to search and review these nonradiologic data are not well characterized. We assessed the gross frequency and pattern of EMR usage in the interpretation of diagnostic CT and MRI examinations. We defined nonradiologic EMR data as laboratory data, nonimaging specialty report, clinical note, and administrative data not available on PACS. For abdominal, neuroradiologic, and musculoskeletal CT and MRI, we prospectively recorded the time required for image analysis (including prior imaging studies and their reports), nonradiologic EMR use, and initial report drafting by fellows and staff in randomized sessions. We assessed EMR use as a fraction of work activity and according to technique, subspecialty, inpatient status, and radiologist experience. We observed 372 CT and MRI interpretations by 33 radiologists. For CT, radiologists used the EMR in 34% of abdominal, 57% of neuroradiologic, and 38% of musculoskeletal interpretations. For MRI, EMR was used in 73% of abdominal, 56% of neuroradiologic, and 33% of musculoskeletal interpretations. For CT, EMR usage comprised 18%, 14%, and 18% of diagnostic effort (image analysis plus EMR use) for abdominal, neuroradiologic, and musculoskeletal interpretations, respectively; for MRI, EMR usage comprised 21%, 16%, and 15% of diagnostic effort for abdominal, neuroradiologic, and musculoskeletal interpretations, respectively. Frequency of EMR use was significantly greater for neuroradiology CT and abdominal MRI (p < 0.05, Fisher's test). EMR usage was not consistently related to inpatient status for CT or radiologist experience. For CT and MRI interpretation, EMR usage is frequent and comprises a significant fraction of diagnostic effort.

  9. First experiences with multidetector CT in traumatized children

    International Nuclear Information System (INIS)

    Hoermann, Marcus; Scharitzer, Martina; Philipp, M.; Metz, Viktor M.; Lomoschitz, F.

    2003-01-01

    Introduction: The aim of this study was to describe and discuss first experiences with multidetector CT (MDCT) in the assessment of traumatized children. Material and methods: Since the implementation of a MDCT scanner in April 2002, 85 children (31 girls, 54 boys with a mean age of 9.2 years) consecutively underwent MDCT (Siemens, Erlangen, Germany) with different protocols depending on age, weight, trauma mechanism and clinical presentation. In all patients in whom pathology was suspected, multiplanar reformations (MPR) in coronal and or sagittal orientation was performed. Examinations were evaluated by two radiologists retrospectively and in consensus. Results: In 55 (65%) children, a MDCT solely of the head was performed, in 46 there was no pathology found. In six (7%), head and facial bones were scanned. Head and abdomen was examined in two (2%), in two (2%) the abdomen only and in one (1%) the pelvis solely. Scans of the spine were obtained in seven (8%) children. A thorax and abdomen examination only was obtained in one (1%) child each. In 11 (13%) children, a polytrauma protocol was performed. In all patients, the time of examination did not exceed 17 min, including setup time. All children survived at the writing of this report. Conclusion: MDCT was promising in the management of traumatized children and seems to shorten the necessary time to reach diagnosis and to initiate life-saving treatment

  10. First experiences with multidetector CT in traumatized children

    Energy Technology Data Exchange (ETDEWEB)

    Hoermann, Marcus E-mail: marcus.hoermann@univie.ac.at; Scharitzer, Martina; Philipp, M.; Metz, Viktor M.; Lomoschitz, F

    2003-10-01

    Introduction: The aim of this study was to describe and discuss first experiences with multidetector CT (MDCT) in the assessment of traumatized children. Material and methods: Since the implementation of a MDCT scanner in April 2002, 85 children (31 girls, 54 boys with a mean age of 9.2 years) consecutively underwent MDCT (Siemens, Erlangen, Germany) with different protocols depending on age, weight, trauma mechanism and clinical presentation. In all patients in whom pathology was suspected, multiplanar reformations (MPR) in coronal and or sagittal orientation was performed. Examinations were evaluated by two radiologists retrospectively and in consensus. Results: In 55 (65%) children, a MDCT solely of the head was performed, in 46 there was no pathology found. In six (7%), head and facial bones were scanned. Head and abdomen was examined in two (2%), in two (2%) the abdomen only and in one (1%) the pelvis solely. Scans of the spine were obtained in seven (8%) children. A thorax and abdomen examination only was obtained in one (1%) child each. In 11 (13%) children, a polytrauma protocol was performed. In all patients, the time of examination did not exceed 17 min, including setup time. All children survived at the writing of this report. Conclusion: MDCT was promising in the management of traumatized children and seems to shorten the necessary time to reach diagnosis and to initiate life-saving treatment.

  11. Initial Results of Using Daily CT Localization to Correct Portal Error in Prostate Cancer

    International Nuclear Information System (INIS)

    Lattanzi, Joseph; McNeely, Shawn; Barnes, Scott; Das, Indra; Schultheiss, Timothy E; Hanks, Gerald E.

    1997-01-01

    Purpose: To evaluate the use of daily CT simulation in prostate cancer to correct errors in portal placement and organ motion. Improved localization with this technique should allow the reduction of target margins and facilitate dose escalation in high risk patients while minimizing the risk of normal tissue morbidity. Methods and Materials : Five patients underwent standard CT simulation with the alpha cradle cast, IV contrast, and urethrogram. All were initially treated to 46 Gy in a four field conformal technique which included the prostate, seminal vesicles and pelvic lymph nodes (GTV 1 ). The prostate or prostate and seminal vesicles (GTV 2 ) then received 56 Gy with a 1.0 cm margin to the PTV. At 50 Gy a second CT simulation was performed with IV contrast, urethrogram and the alpha cradle secured to a rigid sliding board. The prostate was contoured, a new isocenter generated, and surface markers placed. Prostate only treatment portals for the final conedown (GTV 3 ) were created with 0.25 cm isodose margins to the PTV. The final six fractions in 2 patients with favorable disease and eight fractions in 3 patients with unfavorable disease were delivered using the daily CT technique. On each treatment day the patient was placed in his cast on the sliding board and a CT scan performed. The daily isocenter was calculated in the A/P and lateral dimension and compared to the 50 Gy CT simulation isocenter. Couch and surface marker shifts were calculated to produce perfect portal alignment. To maintain positioning, the patient was transferred to a gurney while on the sliding board in his cast, transported to the treatment room and then transferred to the treatment couch. The patient was then treated to the corrected isocenter. Portal films and real time images were obtained for each portal. Results: Utilizing CT-CT image registration (fusion) of the daily and 50 Gy baseline CT scans the isocenter changes were quantified to reflect the contribution of positional

  12. Adenosine-stress dynamic real-time myocardial perfusion CT and adenosine-stress first-pass dual-energy myocardial perfusion CT for the assessment of acute chest pain: Initial results

    Energy Technology Data Exchange (ETDEWEB)

    Weininger, Markus [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Department of Medicine, Division of Cardiology, Medical University of South Carolina, Charleston, SC (United States); Ramachandra, Ashok [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Fink, Christian [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University (Germany); Rowe, Garrett W.; Costello, Philip [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Henzler, Thomas [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University (Germany)

    2012-12-15

    Purpose: Recent innovations in CT enable the evolution from mere morphologic imaging to dynamic and functional testing. We describe our initial experience performing myocardial stress perfusion CT in a clinical population with acute chest pain. Methods and materials: Myocardial stress perfusion CT was performed on twenty consecutive patients (15 men, 5 women; mean age 65 ± 8 years) who presented with acute chest pain and were clinically referred for stress/rest SPECT and cardiac MRI. Prior to CT each patient was randomly assigned either to Group A or to Group B in a consecutive order (10 patients per group). Group A underwent adenosine-stress dynamic real-time myocardial perfusion CT using a novel “shuttle” mode on a 2nd generation dual-source CT. Group B underwent adenosine-stress first-pass dual-energy myocardial perfusion CT using the same CT scanner in dual-energy mode. Two experienced observers visually analyzed all CT perfusion studies. CT findings were compared with MRI and SPECT. Results: In Group A 149/170 myocardial segments (88%) could be evaluated. Real-time perfusion CT (versus SPECT) had 86% (84%) sensitivity, 98% (92%) specificity, 94% (88%) positive predictive value, and 96% (92%) negative predictive value in comparison with perfusion MRI for the detection of myocardial perfusion defects. In Group B all myocardial segments were available for analysis. Compared with MRI, dual-energy myocardial perfusion CT (versus SPECT) had 93% (94%) sensitivity, 99% (98%) specificity, 92% (88%) positive predictive value, and 96% (94%) negative predictive value for detecting hypoperfused myocardial segments. Conclusion: Our results suggest the clinical feasibility of myocardial perfusion CT imaging in patients with acute chest pain. Compared to MRI and SPECT both, dynamic real-time perfusion CT and first-pass dual-energy perfusion CT showed good agreement for the detection of myocardial perfusion defects.

  13. Adenosine-stress dynamic real-time myocardial perfusion CT and adenosine-stress first-pass dual-energy myocardial perfusion CT for the assessment of acute chest pain: Initial results

    International Nuclear Information System (INIS)

    Weininger, Markus; Schoepf, U. Joseph; Ramachandra, Ashok; Fink, Christian; Rowe, Garrett W.; Costello, Philip; Henzler, Thomas

    2012-01-01

    Purpose: Recent innovations in CT enable the evolution from mere morphologic imaging to dynamic and functional testing. We describe our initial experience performing myocardial stress perfusion CT in a clinical population with acute chest pain. Methods and materials: Myocardial stress perfusion CT was performed on twenty consecutive patients (15 men, 5 women; mean age 65 ± 8 years) who presented with acute chest pain and were clinically referred for stress/rest SPECT and cardiac MRI. Prior to CT each patient was randomly assigned either to Group A or to Group B in a consecutive order (10 patients per group). Group A underwent adenosine-stress dynamic real-time myocardial perfusion CT using a novel “shuttle” mode on a 2nd generation dual-source CT. Group B underwent adenosine-stress first-pass dual-energy myocardial perfusion CT using the same CT scanner in dual-energy mode. Two experienced observers visually analyzed all CT perfusion studies. CT findings were compared with MRI and SPECT. Results: In Group A 149/170 myocardial segments (88%) could be evaluated. Real-time perfusion CT (versus SPECT) had 86% (84%) sensitivity, 98% (92%) specificity, 94% (88%) positive predictive value, and 96% (92%) negative predictive value in comparison with perfusion MRI for the detection of myocardial perfusion defects. In Group B all myocardial segments were available for analysis. Compared with MRI, dual-energy myocardial perfusion CT (versus SPECT) had 93% (94%) sensitivity, 99% (98%) specificity, 92% (88%) positive predictive value, and 96% (94%) negative predictive value for detecting hypoperfused myocardial segments. Conclusion: Our results suggest the clinical feasibility of myocardial perfusion CT imaging in patients with acute chest pain. Compared to MRI and SPECT both, dynamic real-time perfusion CT and first-pass dual-energy perfusion CT showed good agreement for the detection of myocardial perfusion defects.

  14. Initial state radiation experiment at MAMI

    Energy Technology Data Exchange (ETDEWEB)

    Mihovilovič, M.; Merkel, H. [Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, Johann-Joachim-Becher-Weg 45, 55128 Mainz (Germany); Collaboration: A1-Collaboration

    2013-11-07

    In an attempt to contribute further insight into the discrepancy between the Lamb shift and elastic scattering determinations of the proton charge radius, a new experiment at MAMI is underway, aimed at measuring proton form-factors at very low momentum transfers by using a new technique based on initial state radiation. This paper reports on first findings of the pilot measurement performed in 2010, whose main goal was to check the feasibility of the proposed experiment and to recognize and overcome potential obstacles before running the full experiment in 2013.

  15. Ultra-high pitch chest computed tomography at 70 kVp tube voltage in an anthropomorphic pediatric phantom and non-sedated pediatric patients. Initial experience with 3{sup rd} generation dual-source CT

    Energy Technology Data Exchange (ETDEWEB)

    Hagelstein, Claudia; Henzler, Thomas; Haubenreisser, Holger; Meyer, Mathias; Sudarski, Sonja; Schoenberg, Stefan O.; Neff, K. Wolfgang; Weis, Meike [Univ. Medical Center Mannheim (Germany). Inst. of Clinical Radiology and Nuclear Medicine

    2016-07-01

    Minimizing radiation dose while at the same time preserving image quality is of particular importance in pediatric chest CT. Very recently, CT imaging with a tube voltage of 70 kVp has become clinically available. However, image noise is inversely proportional to the tube voltage. We aimed to investigate radiation dose and image quality of pediatric chest CT performed at 70 kVp in an anthropomorphic pediatric phantom as well as in clinical patients. An anthropomorphic pediatric phantom, which resembles a one-year-old child in physiognomy, was scanned on the 3{sup rd} generation dual-source CT (DSCT) system at 70 kVp and 80 kVp and a fixed ultra low tube-current of 8 mAs to solely evaluate the impact of lowering tube voltage. After the phantom measurements, 18 pediatric patients (mean 29.5 months; range 1-91 months; 21 examinations) underwent 3.2 high-pitch chest CT on the same DSCT system at 70 kVp tube voltage without any sedation. Radiation dose and presence of motion artifacts was compared to a retrospectively identified patient cohort examined at 80 kVp on a 16-slice single-source-CT (SSCT; n = 15; 14/15 with sedation; mean 30.7 months; range 0-96 months; pitch = 1.5) or on a 2{sup nd} generation DSCT without any sedation (n = 6; mean 32.8 months; range 4-61 months; pitch = 3.2). Radiation dose in the phantom scans was reduced by approximately 40% when using a tube voltage of 70 kVp instead of 80 kVp. In the pediatric patient group examined at 70 kVp age-specific effective dose (ED; mean 0.5 ± 0.2 mSv) was significantly lower when compared to the retrospective cohort scanned at 80 kVp on the 16-slice-SSCT (mean ED: 1.0 ± 0.3 mSv; p < 0.0001) and also considerably lower when compared to the cohort scanned at 80 kVp on the 2{sup nd} generation DSCT (mean ED: 0.9 ± 0.5 mSv). None of the prospective, sedation-free CT examinations showed any motion artifacts whereas 13/15 examinations of the retrospective patient cohort scanned at 80 kVp with a pitch of 1

  16. Diagnostic potential of PET/CT using a {sup 68}Ga-labelled prostate-specific membrane antigen ligand in whole-body staging of renal cell carcinoma: initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Sawicki, Lino M.; Buchbender, Christian; Boos, Johannes; Antoch, Gerald [University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Dusseldorf (Germany); Giessing, Markus [University Dusseldorf, Medical Faculty, Department of Urology, Dusseldorf (Germany); Ermert, Johannes [Juelich Research Center, Institute of Neuroscience and Medicine, INM-5: Nuclear Chemistry, Juelich (Germany); Antke, Christina; Hautzel, Hubertus [University Dusseldorf, Medical Faculty, Department of Nuclear Medicine, Dusseldorf (Germany)

    2017-01-15

    To evaluate the diagnostic potential of whole-body PET/CT using a {sup 68}Ga-labelled PSMA ligand in renal cell carcinoma (RCC). Six patients with histopathologically proven RCC underwent {sup 68}Ga-PSMA PET/CT. Each PET/CT scan was evaluated in relation to lesion count, location and dignity. SUVmax was measured in primary tumours and PET-positive metastases. Tumour-to-background SUVmax ratios (TBR{sub SUVmax}) were calculated for primary RCCs in relation to the surrounding normal renal parenchyma. Metastasis-to-background SUVmax ratios (MBR{sub SUVmax}) were calculated for PET-positive metastases in relation to gluteal muscle. Five primary RCCs and 16 metastases were evaluated. The mean SUVmax of the primary RCCs was 9.9 ± 9.2 (range 1.7 - 27.2). Due to high uptake in the surrounding renal parenchyma, the mean TBR{sub SUVmax} of the primary RCCs was only 0.2 ± 0.3 (range 0.02 - 0.7). Eight metastases showed focal {sup 68}Ga-PSMA uptake (SUVmax 9.9 ± 8.3, range 3.4 - 25.6). The mean MBR{sub SUVmax} of these PET-positive metastases was 11.7 ± 0.2 (range 4.4 - 28.1). All PET-negative metastases were subcentimetre lung metastases. {sup 68}Ga-PSMA PET/CT appears to be a promising method for detecting RCC metastases. However, no additional diagnostic value in assessing the primary tumour was found. (orig.)

  17. Initial clinical experience with the heartstring

    International Nuclear Information System (INIS)

    Kazui, Toshinobu; Doi, Hirosato; Suzuki, Masato; Okamoto, Takashi; Koshima, Ryuji; Sugiki, Kenji; Ohno, Takemi

    2006-01-01

    The Heartstring is one of the devices that enable proximal anastomosis without clamping the aorta. We have applied the device not only to low-risk patients with normal aortas but also to high-risk patients with diseased aortas. The purpose of this study was to investigate the initial outcomes of using this device. The Heartstring was used on 87 patients between January and December 2004. The patients comprised 62 men and 25 women 48-86 years old (mean 68.4±8.4 years). The ascending aorta was evaluated by computed tomography (CT) scanning before surgery. If a patient's aorta was severely calcified, epiaortic echocardiography was performed. The aortas were ranked into four grades, and the preoperative patient's status were evaluated by the EuroSCORE. Angiography was performed on the third postoperative day. CT scanning revealed that 74 patients had no calcification in the ascending aorta, 10 patients had scattered calcification, and 3 patients had plate-like calcification. The EuroSCORE was 6.86±1.03. We performed 93 proximal anastomoses and 149 distal anastomoses. The average distal anastomosis was 1.6±0.6 sites per graft. Of the distal anastomoses, 74.2% were to the circumflex artery territory. Postoperative coronary angiography revealed that all grafts were patent. The Heartstring facilitates safe proximal anastomosis, even in high-risk patients. Their short-term outcome was good. The device assists in bypassing circumflex artery territory. Long-term follow-up is necessary. (author)

  18. WE-FG-207B-01: BEST IN PHYSICS (IMAGING): Abdominal CT with Three K-Edge Contrast Materials Using a Whole-Body Photon-Counting Scanner: Initial Results of a Large Animal Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lakshmanan, M; Symons, R; Cork, T; Davies-Venn, C; Rice, K; Malayeri, A; Sandfort, V; Bluemke, D; Pourmorteza, A [National Institutes of Health Clinical Center, Bethesda, MD (United States)

    2016-06-15

    Purpose: To demonstrate the feasibility of in vivo three-material decomposition techniques using photon-counting CT (PCCT) with possible advantage of resolving arterial and venous flow of an organ simultaneously. Methods: Abdominal PCCT scans were acquired using a prototype whole-body PCCT with four energy thresholds (25/50/75/90keV) in a canine. Bismuth subsalicylate (60 mg) was administered orally one day prior to scanning. Immediately prior to CT scan, gadoteric acid (60 ml, Dotarem, Guerbet) was intravenously injected, followed in ten minutes by a 20mL injection of iodinated contrast (iopamidol 370 mg/mL, Bracco). Scans were acquired every ∼20 seconds, starting from the time of iodine injection. Linear material decomposition was performed using the least mean squares method to create concentration maps of iodine, gadolinium, and bismuth. The method was calibrated to vials with known concentrations of materials placed next to the animal. The accuracy of this method was tested on vials with known concentrations. Results: The material decomposition algorithm’s accuracy was confirmed to be within ±4mM in the test vials. In the animal, we could estimate the concentration of gadolinium in delayed-enhanced phase (10 minutes post-injection) in the abdomen. We could follow the wash-in and wash-out of iodine in arterial, venous, and excretory flow of the kidneys (20s, 80s, and 120s post-iodine injection) while gadolinium was present in the delayed-enhanced phase. Bismuth, which was used as a contrast agent for the gastro-intestinal tract, was easily differentiable from the other two contrast agents in the small intestine. Conclusion: This study shows the feasibility of using photon-counting CT with four energy thresholds to differentiate three k-edge contrast agents in vivo. This can potentially reduce radiation dose to patients by combining arterial and venous phases into a single acquisition.

  19. The analysis of initial cranial CT of early hematoma enlargement in spontaneous intracerebral hemorrhage

    OpenAIRE

    BEI Yu-zhang; CHEN Ben-yang; QI Hao-bo; ZHOU Zheng-ping; LI Yu-bo

    2012-01-01

    Objective To investigate the predictive effect of initial cranial CT on early hematoma enlargement in spontaneous intracerebral hemorrhage. Methods Three hundred patients with spontaneous intracerebral hemorrhage within 6 hours after onset were studied. Chi-square test and logistic regression analysis were used to detect the related factors which may indicate hematoma enlargement. Results Sixty-one (20.33% ) patients presented hematoma enlargement on cranial CT. Single factor and multivariate...

  20. Preliminary results on the role of PET/CT in initial staging, restaging, and management of lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Malamitsi, J. [Department of PET/CT, Diagnostic and Therapeutic Center of Athens, Hygeia, Athens (Greece): Department of Medical Physics, Medical School, University of Athens (Greece)]. E-mail: j.malamitsi@yahoo.gr; Valotassiou, B. [Department of PET/CT, Diagnostic and Therapeutic Center of Athens, Hygeia, Athens (Greece); Iliadis, K. [Thoracic Surgical Department, Diagnostic and Therapeutic Center of Athens, Hygeia, Athens (Greece); Kosmidis, P. [2nd Medical Oncology Department, Diagnostic and Therapeutic Center of Athens, Hygeia, Athens (Greece); Laspas, F. [Department of PET/CT, Diagnostic and Therapeutic Center of Athens, Hygeia, Athens (Greece); Vasilaki, M. [Oncologist, Diagnostic and Therapeutic Center of Athens, Hygeia, Athens (Greece); Pipini, E. [Thoracic Medicine Clinic, Diagnostic and Therapeutic Center of Athens, Hygeia, Athens (Greece); Petounis, A. [1st Internal Medicine and Oncology Department, Diagnostic and Therapeutic Center of Athens, Hygeia, Athens (Greece); Gogou, L. [Department of PET/CT, Diagnostic and Therapeutic Center of Athens, Hygeia, Athens (Greece); Pagou, M. [Department of PET/CT, Diagnostic and Therapeutic Center of Athens, Hygeia, Athens (Greece); Dalianis, K. [Department of PET/CT, Diagnostic and Therapeutic Center of Athens, Hygeia, Athens (Greece); Efthimiadou, R. [Department of PET/CT, Diagnostic and Therapeutic Center of Athens, Hygeia, Athens (Greece); Andreou, J. [Department of PET/CT, Diagnostic and Therapeutic Center of Athens, Hygeia, Athens (Greece)

    2006-12-20

    Aim: To determine true-positive and true-negative rates of PET/CT studies in the staging of lung cancer as compared with conventional imaging (CT and bone scan and occasionally MRI) and the impact of PET/CT on the treatment strategy in patients with lung cancer. Materials and method: Twenty patients (21 studies) with known or suspected lung cancer (14 patients with non-small-cell lung cancer (NSCLC), three patients with small-cell lung cancer (SCLC), three patients with solitary pulmonary nodule underwent initial staging (seven studies) or restaging (14 studies) with combined FDG PET and CT scans on a PET/CT tomograph. PET/CT images were evaluated separately by two nuclear medicine physicians and two radiologists specialized on PET, CT, and MRI. Histology results and a more than 6 months follow-up served as the reference standards. Results: Accurate diagnosis was achieved on 16 studies. Site-by-site analysis gave the following results: 16 true-positive sites (seven on histology, nine on >6 months follow-up), six true-negative sites (two on histology, four on >6 months follow-up). On PET/CT, six patients were correctly down-staged, three patients were correctly upstaged and seven patients were diagnosed correctly as being on the same stage (2/7 with increase of extent of disease, 5/7 with the same extent of disease). One patient was falsely upstaged and three patients were falsely down-staged. On the basis of PET/CT results, change of management was induced in six patients, while in 14 patients there was no change induced. In five cases PET/CT was partially accurate: on site-by-site analysis, four sites proved true positive (on histology), one site false positive (on histology), and four sites false negative (one on histology, three on >6 months follow-up). Conclusion: In our early experience, PET/CT contributed significantly to correct staging and management of patients with lung cancer.

  1. Preliminary results on the role of PET/CT in initial staging, restaging, and management of lung cancer

    International Nuclear Information System (INIS)

    Malamitsi, J.; Valotassiou, B.; Iliadis, K.; Kosmidis, P.; Laspas, F.; Vasilaki, M.; Pipini, E.; Petounis, A.; Gogou, L.; Pagou, M.; Dalianis, K.; Efthimiadou, R.; Andreou, J.

    2006-01-01

    Aim: To determine true-positive and true-negative rates of PET/CT studies in the staging of lung cancer as compared with conventional imaging (CT and bone scan and occasionally MRI) and the impact of PET/CT on the treatment strategy in patients with lung cancer. Materials and method: Twenty patients (21 studies) with known or suspected lung cancer (14 patients with non-small-cell lung cancer (NSCLC), three patients with small-cell lung cancer (SCLC), three patients with solitary pulmonary nodule underwent initial staging (seven studies) or restaging (14 studies) with combined FDG PET and CT scans on a PET/CT tomograph. PET/CT images were evaluated separately by two nuclear medicine physicians and two radiologists specialized on PET, CT, and MRI. Histology results and a more than 6 months follow-up served as the reference standards. Results: Accurate diagnosis was achieved on 16 studies. Site-by-site analysis gave the following results: 16 true-positive sites (seven on histology, nine on >6 months follow-up), six true-negative sites (two on histology, four on >6 months follow-up). On PET/CT, six patients were correctly down-staged, three patients were correctly upstaged and seven patients were diagnosed correctly as being on the same stage (2/7 with increase of extent of disease, 5/7 with the same extent of disease). One patient was falsely upstaged and three patients were falsely down-staged. On the basis of PET/CT results, change of management was induced in six patients, while in 14 patients there was no change induced. In five cases PET/CT was partially accurate: on site-by-site analysis, four sites proved true positive (on histology), one site false positive (on histology), and four sites false negative (one on histology, three on >6 months follow-up). Conclusion: In our early experience, PET/CT contributed significantly to correct staging and management of patients with lung cancer

  2. Translation of field-reversed configurations in the FRX C/T experiment

    International Nuclear Information System (INIS)

    Rej, D.J.; Armstrong, W.T.; Chrien, R.E.

    1984-01-01

    One of the unique features inherent to compact toroids is the potential ability to translate the plasma along its geometric axis. CT translation has proven useful in reactor design studies, and has been the focus of several experimental investigations. In this paper, we report on the initial results from translation experiments performed with the field-reversed configuration (FRC) plasmas generated in the FRX-C/T device

  3. Translation of field-reversed configurations in the FRX C/T experiment

    Energy Technology Data Exchange (ETDEWEB)

    Rej, D.J.; Armstrong, W.T.; Chrien, R.E.; Klingner, P.L.; Linford, R.K.; McKenna, K.F.; Milroy, R.D.; Sherwood, E.G.; Siemon, R.E.; Tuszewski, M.

    1984-01-01

    One of the unique features inherent to compact toroids is the potential ability to translate the plasma along its geometric axis. CT translation has proven useful in reactor design studies, and has been the focus of several experimental investigations. In this paper, we report on the initial results from translation experiments performed with the field-reversed configuration (FRC) plasmas generated in the FRX-C/T device.

  4. Novel characteristics of CtIP at damage-induced foci following the initiation of DNA end resection

    International Nuclear Information System (INIS)

    Fujisawa, Hiroshi; Fujimori, Akira; Okayasu, Ryuichi; Uesaka, Mitsuru; Yajima, Hirohiko

    2015-01-01

    Highlights: • CtIP becomes hyperphosphorylated and forms foci following cell irradiation. • CtIP accumulates in foci subsequent to the peak of hyperphosphorylation. • CtIP is maintained in a hypophosphorylated state at later times. • CtIP is continuously recruited to DNA double strand breaks downstream of resection. • CtIP presumably have a distinct role following the initiation of resection. - Abstract: Homologous recombination (HR) is a major repair pathway for DNA double strand breaks (DSBs), and end resection, which generates a 3′-single strand DNA tail at the DSB, is an early step in the process. Resection is initiated by the Mre11 nuclease together with CtIP. Here, we describe novel characteristics of CtIP at DSBs. At early times following exposure of human cells to ionizing radiation, CtIP localized to the DSB, became hyperphosphorylated and formed foci in an ATM-dependent manner. At later times, when the initiation of resection had occurred, CtIP foci persist but CtIP is maintained in a hypophosphorylated state, which is dependent on ATM and ATR. Exposure to cycloheximide revealed that CtIP turns over at DSB sites downstream of resection. Our findings provide strong evidence that CtIP is continuously recruited to DSBs downstream of both the initiation and extension step of resection, strongly suggesting that CtIP has functions in addition to promoting the initiation of resection during HR

  5. Multi-slice CT urography after diuretic injection: initial results

    Energy Technology Data Exchange (ETDEWEB)

    Nolte-Ernsting, C.C.A.; Wildberger, J.E.; Schmitz-Rode, T.; Guenther, R.W. [Technische Univ. Aachen (Germany). Dept. of Diagnostic Radiology; Borchers, H. [Technische Univ. Aachen (Germany). Dept. of Urology

    2001-03-01

    Purpose: To investigate the feasibility of CT urography (CTU) using a multi-slice (MS) scanner and to find out whether a low-dose diuretic injection is advantageous for the opacification of the urinary tract. Methods: MS-CTU was performed in 21 patients with urologic diseases. In 5/21 patients, 250 ml of physiologic saline solution were injected. In 16/21 patients, 10 mg of furosemide were injected 3-5 min before contrast material administration. A 4x2.5 mm collimation with a pitch of 1.25 and a tube curent of 100-150 mA were used. Scan time was 12-16 sec. 3 mm thin axial images with an overlap of 67% were reconstructed. Multiplanar maximum intensity projection (MIP) images were postprocessed to obtain urographic views. Bone structures were eliminated using the volume-of-interest method. Results: Furosemide-enhanced MS-CTU achieved either near complete or complete opacification in 30/32 (94%) ureters and in 32/32 (100%) pelvicaliceal systems up to a serum creatinine of 150 {mu}mol/l. In our series, only one CTU scan per patient was needed to obtain a diagnostic urogram after 10 min of contrast material injection. Ureteral compression was not necessary. When physiologic saline solution was used instead of furosemide, the radiopacity inside the enhanced pelvicalices was 4-5 times higher and more inhomogeneous. Diuretic-enhanced MS-CTU was more accurate in the depiction of pelvicaliceal details. In combination with furosemide, calculi were well identified inside the opacified urine and were safely differentiated from phleboliths. Postprocessing times of up to 20 minutes were problematic as were contrast-enhanced superimposing bowel loops on MIP images. Conclusion: Preliminary results demonstrate a good feasibility of furosemide-enhanced MS-CTU for obtaining detailed visualization of the entire upper urinary tract. (orig.) [German] Ziel: Untersuchung zur Durchfuehrbarkeit der CT Urographie (CTU) mit einem Multidetektor(MD)-Computertomographen und ob eine

  6. Unenhanced multidetector CT (CT KUB) in the initial imaging of suspected acute renal colic: evaluating a new service

    International Nuclear Information System (INIS)

    Chowdhury, F.U.; Kotwal, S.; Raghunathan, G.; Wah, T.M.; Joyce, A.; Irving, H.C.

    2007-01-01

    Aim: To evaluate a new imaging pathway for the investigation of patients presenting with suspected acute renal colic. Materials and methods: A retrospective review of 500 consecutive cases of suspected acute renal colic was undertaken to evaluate the initial results of a new imaging pathway introduced at our institution, which completely replaced the intravenous urogram (IVU) with unenhanced multidetector CT (CT KUB). Results: The positive rate for urolithiasis was 44% (221/500), the negative rate 46% (229/500) and the rate of other significant findings was 12% (59/500). Female patients had a low positive rate compared with male patients (27.5 versus 57.5%; p < 0.001). Urological intervention was required in 28% (61/221) and these patients had a larger average stone size (6.6 versus 3.7 mm; p < 0.001) and the stone was located more proximally. Out-of-hours imaging was performed in 37% (186/500), and these patients had a higher positive rate (52 versus 40%; p < 0.001). Other findings included a wide range of acute non-urological conditions. Conclusion: The feasibility of replacing the acute IVU with CT KUB in the initial assessment of suspected acute renal colic was demonstrated in the present study. The technique enables rapid diagnosis of urolithiasis, stratification of patients likely to proceed to urological intervention, and prompt diagnosis of a variety of other acute pathological conditions

  7. Initial deuterium pellet experiments on FTU

    International Nuclear Information System (INIS)

    Snipes, J.A.

    1993-01-01

    Initial experiments have been performed with the Single Pellet INjector (SPIN) on FTU. SPIN is a two-stage cryogenic deuterium pellet injector capable of injection,a pellets with velocities up to 2.5 km/s. The nominal pellet mass for these experiments was approximately 1 x 10 20 atoms. These initial pellet experiments concentrated on studying pellet penetration under a variety of plasma conditions to compare with code predictions and to examine toroidal particle transport. The principal diagnostics used were two fast (∼1 μsec) photomultiplier tubes at nearly opposite toroidal locations with H α (D α ) interference filters (λ = 656 nm), a microwave cavity for pellet mass and velocity, a vertical array of soft x ray diodes without filters looking down onto the pellet, a DCN interferometer for electron density profiles, and a Michelson ECE system for electron temperature profiles. The time integral of the absolutely calibrated fast H α signal appears to give reasonable agreement with the expected pellet mass. Toroidal transport of deuterium ions from the pellet to nearly the opposite side of the tokamak agrees with calculated thermal deuterium velocities near the plasma edge. Comparison of the experimental results with code calculations using the Neutral Gas Shielding model show good agreement for the post-pellet electron temperature and density profiles and the H α profiles in some cases. Calculated penetration distances agree within 20%

  8. Computerized tomography(CT) in patients with head injuries, assessment of outcome based upon initial clinical findings and initial CT scans

    International Nuclear Information System (INIS)

    Espersen, J.O.; Petersen, O.F.

    1982-01-01

    In this study, which comprises 144 consecutive head injuries, the initial clinical assessment and the findings of the initial CT scan are relatd to the outcome. The mortality is related to the patient's level of consiousness and pupillary light reflex on admission. The disability rate (= number of disabled/number of survivors) was independent of the level of consiousness but closely related to pupillary light reaction. Diminished and obliterated basal cisterns were bad prognostic signs, with a mortality rate of 66% in the latter group. Both disability and mortality increase with the number of different lesion types. (Author)

  9. Imaging of blunt pancreatic trauma: The value of initial and sequential CT examinations

    International Nuclear Information System (INIS)

    Szmigielski, W.; Darweesh, A.; Kassem, H.; Alhilli, S.

    2008-01-01

    The purpose of the study was to assess the value of initial, repeated and sequential computed tomography (CT) in patients with blunt pancreatic trauma, and then define and correlate CT findings with endoscopic retrograde cholangiopancreatography (ERCP) or magnetic resonance cholangiopancreatography (MRCP), ultrasound (US), both laboratory and surgical findings. This retrospective study covers an eight-year period from 1999 to 2007. The material includes 21 patients (17 males and 4 females) with confirmed pancreatic injury. CT was performed on admission in all cases and in 15 cases follow-up CT was performed from 24 hrs to 14 days later. US was performed in 9 cases, ERCP in 8 cases and MRCP in one case. Serum amylase level was obtained at the admission in all cases. The CT at admission was positive in 17 patients (81.0%); the diagnosis was missed in 4 patients (19.0%), all performed on single row spiral CT. In all these four cases repeated CT was positive. ERCP showed rupture of the main pancreatic duct in 7 cases, one was inconclusive. One MRCP was positive. The serum amylase was elevated in 14 cases (66.7%) Specific CT features in initial and repeated examinations together were: organ fracture - 33.3%, swelling - 38.1%, haematoma/ contusion - 38.1%, fluid between splenic vein and pancreas - 19.0%. Non-specific features were: thickening of anterior-renal fascia- 23.8%, fluid in lesser sac - 28.6%, extra peritoneal fluid - 42.9%, associated splenic injury -14.3% and intraperitoneal fluid - 38.1%. On retrospective analysis, two out of four false negative CT results could have been avoided. No correlation between the CT features and the outcome of surgical and conservative management could be found in this study. A proper technique and accurate reading of images are mandatory for the diagnosis of pancreatic injury. When CT performed on admission is negative and there is abdominal pain and an elevated serum amylase, CT examination should be repeated within 24-48 hours

  10. CT and MRI evaluation of orbital tumors: our experience

    International Nuclear Information System (INIS)

    Cabrini, Marcelo; Docampo, Jorge; Martinez, Manuel; Bruno, Claudio; Morales, Carlos

    2007-01-01

    Purpose: To show our experience in the evaluation of orbital masses on computed tomography (CT) and magnetic resonance imaging (MRI). To describe their most important findings and epidemiological features found on literature review, related to their differential diagnosis. Materials and methods: During a 48-months period of time, 26 patients (13 male, 13 female; age range, 3 to 75 years) with orbital tumors were evaluated. Seventeen patients underwent MR scans, 8 underwent CT scans, and one underwent both imaging methods. It was employed 0,5 and 1 Tesla MR scanners, and axial-helical CT scanners. Results: Benign lesions were found on 7 patients (cavernous hemangioma [n=2], meningioma [n=1], epidermoid cyst [n=1], dermoid cyst [n=1], lipoma [n=1], orbital vein deformity [n=1]). It was found lesions with undetermined behavior (optical nerve glioma [n=2]), and malignant ones were found on 17 patients (metastatic lesions [n=5], non- Hodgkin's lymphoma [n=3], hemangiopericytoma [n=2], retinoblastoma [n=2], rhabdomyosarcoma [n=2], melanoma [n=1], and lacrimal adenocarcinoma [n=1]). Conclusion: In our experience, 65.4% was malignant tumors (orbital metastasis was the most common; 19.2%). More than one-quarter was benign tumor, where cavernous hemangioma was the most frequent. (author) [es

  11. Barrier experiment: Shock initiation under complex loading

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-01-12

    The barrier experiments are a variant of the gap test; a detonation wave in a donor HE impacts a barrier and drives a shock wave into an acceptor HE. The question we ask is: What is the trade-off between the barrier material and threshold barrier thickness to prevent the acceptor from detonating. This can be viewed from the perspective of shock initiation of the acceptor subject to a complex pressure drive condition. Here we consider key factors which affect whether or not the acceptor undergoes a shock-to-detonation transition. These include the following: shock impedance matches for the donor detonation wave into the barrier and then the barrier shock into the acceptor, the pressure gradient behind the donor detonation wave, and the curvature of detonation front in the donor. Numerical simulations are used to illustrate how these factors affect the reaction in the acceptor.

  12. [Virtual CT-pneumocystoscopy: indications, advantages and limitations. Our experience].

    Science.gov (United States)

    Regine, Giovanni; Atzori, Maurizio; Buffa, Vitaliano; Miele, Vittorio; Ialongo, Pasquale; Adami, Loredana

    2003-09-01

    The use of CT volume-rendering techniques allows the evaluation of visceral organs without the need for endoscopy. Conventional endoscopic evaluation of the bladder is limited by the invasiveness of the technique and the difficulty exploring the entire bladder. Virtual evaluation of the bladder by three-dimensional CT reconstruction offers potential advantages and can be used in place of endoscopy. This study investigates the sensitivity of virtual CT in assessing lesion of the bladder wall to compare it with that of conventional endoscopy, and outlines the indications, advantages and disadvantages of virtual CT-pneumocystography. Between September 2001 and May 2002, 21 patients with haematuria and positive cystoscopic findings were studied. After an initial assessment by ultrasound, the patients underwent pelvic CT as a single volumetric scan after preliminary air distension of the bladder by means of 12 F Foley catheter. The images were processed on an independent workstation (Advantage 3.0 GE) running dedicated software for endoluminal navigation. The lesions detected by endoscopy were classified as sessile or pedunculated, and according to size (more or less than 5 mm). Finally, the results obtained at virtual cystoscopy were evaluated by two radiologists blinded to the conventional cystoscopy results. Thirty lesions (24 pedunculated, 6 sessile) were detected at conventional cystoscopy in 16 patients (multiple polyposis in 3 cases). Virtual cystoscopy identified 23 lesions (19 pedunculated and 4 sessile). The undetected lesions were pedunculated <5 mm (5 cases) and sessile (2 cases). One correctly identified pedunculated lesion was associated with a bladder stone. Good quality virtual images were obtained in all of the patients. In only one patient with multiple polyposis the quality of the virtual endoscopic evaluation was limited by the patient's intolerance to bladder distension, although identification of the lesions was not compromised. The overall

  13. Prostate brachytherapy in Ghana: our initial experience

    Directory of Open Access Journals (Sweden)

    James Edward Mensah

    2016-10-01

    Full Text Available Purpose: This study presents the experience of a brachytherapy team in Ghana with a focus on technology transfer and outcome. The team was initially proctored by experienced physicians from Europe and South Africa. Material and methods : A total of 90 consecutive patients underwent either brachytherapy alone or brachytherapy in combination with external beam radiotherapy for prostate carcinoma between July 2008 and February 2014 at Korle Bu Teaching Hospital, Accra, Ghana. Patients were classified as low-risk, intermediate, and high-risk according to the National Comprehensive Cancer Network (NCCN criteria. All low-risk and some intermediate risk group patients were treated with seed implantation alone. Some intermediate and all high-risk group patients received brachytherapy combined with external beam radiotherapy. Results: The median patient age was 64.0 years (range 46-78 years. The median follow-up was 58 months (range 18-74 months. Twelve patients experienced biochemical failure including one patient who had evidence of metastatic disease and died of prostate cancer. Freedom from biochemical failure rates for low, intermediate, and high-risk cases were 95.4%, 90.9%, and 70.8%, respectively. Clinical parameters predictive of biochemical outcome included: clinical stage, Gleason score, and risk group. Pre-treatment prostate specific antigen (PSA was not a statistically significant predictor of biochemical failure. Sixty-nine patients (76.6% experienced grade 1 urinary symptoms in the form of frequency, urgency, and poor stream. These symptoms were mostly self-limiting. Four patients needed catheterization for urinary retention (grade 2. One patient developed a recto urethral fistula (grade 3 following banding for hemorrhoids. Conclusions : Our results compare favorably with those reported by other institutions with more extensive experience. We believe therefore that, interstitial permanent brachytherapy can be safely and effectively

  14. Interstitial lung disease in anti-synthetase syndrome: Initial and follow-up CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Debray, Marie-Pierre, E-mail: marie-pierre.debray@bch.aphp.fr [AP-HP, Bichat-Claude Bernard Hospital, Department of Radiology, 46, rue Henri Huchard, 75877 Paris Cedex 18 (France); Borie, Raphael, E-mail: raphael.borie@bch.aphp.fr [AP-HP, Bichat-Claude Bernard Hospital, Department of Pneumology A and Centre de Compétence Maladies Pulmonaires rares, DHU Fire 46, rue Henri Huchard, 75877 Paris Cedex 18 (France); Inserm, U1152, Paris (France); Revel, Marie-Pierre, E-mail: marie-pierre.revel@htd.aphp.fr [AP-HP, Cochin Hospital, Department of Radiology, 27, Rue du Fg Saint Jacques, 75679 Paris Cedex 14 (France); Naccache, Jean-Marc, E-mail: jean-marc.naccache@tnn.aphp.fr [AP-HP, Avicenne Hospital, Department of Pneumology and Centre de Compétence Maladies Pulmonaires rares, Bobigny (France); AP-HP, Tenon Hospital, Department of Pneumology and Centre de Compétence Maladies Pulmonaires rares, 4, rue de la Chine, 75020 Paris (France); Khalil, Antoine, E-mail: antoine.khalil@tnn.aphp.fr [AP-HP, Tenon Hospital, Department of Radiology, 4, rue de la Chine, 75020 Paris (France); Toper, Cécile, E-mail: cecile.toper@gmail.com [AP-HP, Tenon Hospital, Department of Pneumology and Centre de Compétence Maladies Pulmonaires rares, 4, rue de la Chine, 75020 Paris (France); Israel-Biet, Dominique, E-mail: dominique.israel-biet@egp.aphp.fr [Université Paris Descartes and AP-HP, Department of Pneumology, Georges Pompidou European Hospital, 20, rue Leblanc, 75015 Paris (France); and others

    2015-03-15

    Purpose: To describe the initial and follow-up CT features of interstitial lung disease associated with anti-synthetase syndrome (AS-ILD). Materials and methods: Two independent thoracic radiologists retrospectively analysed thin-section CT images obtained at diagnosis of AS-ILD in 33 patients (17 positive for anti-Jo1, 13 for anti-PL12, and three for anti-PL7 antibodies). They evaluated the pattern, distribution and extent of the CT abnormalities. They also evaluated the change in findings during follow-up (median 27 months; range 13–167 months) in 26 patients. Results: At diagnosis, ground-glass opacities (100%), reticulations (87%) and traction bronchiectasis (76%) were the most common CT findings. Consolidations were present in 45% of patients. A non-specific interstitial pneumonia (NSIP), organizing pneumonia (OP) or mixed NSIP-OP CT pattern were observed in 15 out of 33 (45%), seven out of 33 (21%) and eight out of 33 (24%) patients, respectively, whereas the CT pattern was indeterminate in three patients. During follow-up, consolidations decreased or disappeared in 11 out of 12 patients (92%), among which seven within the first 6 months, but honeycombing progressed or appeared in ten out of 26 patients (38%) and overall disease extent increased in nine out of 26 patients (35%). Conclusion: CT features at diagnosis of AS-ILD mainly suggest NSIP and OP, isolated or in combination. Consolidations decrease or disappear in most cases but the disease may progress to fibrosis in more than one third of patients.

  15. Liver transplantations in Bulgaria--initial experience.

    Science.gov (United States)

    Vladov, N; Mihaylov, V; Takorov, I; Vasilevski, I; Lukanova, T; Odisseeva, E; Katzarov, K; Simonova, M; Tomova, D; Konakchieva, M; Petrov, N; Mladenov, N; Sergeev, S; Mutafchiiski, V

    2014-01-01

    The filed of liver transplantation (LT) continues to evolve and is highly effective therapy for many patients with acute and chronic liver failure resulting from a variety of causes. Improvement of perioperative care, surgical technique and immunosuppression in recent years has led to its transformation into a safe and routine procedure with steadily improving results. The aim of this paper is to present the initial experience of the transplant team at Military Medical Academy - Sofia, Bulgaria. For the period of April 2007 - August 2014 the team performed 38 liver transplants in 37 patients (one retransplantation). Patients were followed up prospectively and retrospectively. In 36 (95%) patients a graft from a cadaveric donor was used and in two cases--a right liver grafts from live donor. The mean MELD score of the transplanted patients was 17 (9-40). The preferred surgical technique was "piggyback" with preservation of inferior vena cava in 33 (86%) of the cases and classical technique in 3 (8%) patients. The overall complication rate was 48%. Early mortality rate was 13% (5 patients). The overall 1- and 5-year survival is 81% and 77% respectivelly. The setting of a new LT program is a complex process which requires the effort and effective colaboration of a wide range of speciacialists (hepatologists, surgeons, anesthesiologists, psychologists, therapists, coordinators, etc.) and institutions. The good results are function of a proper selection of the donors and the recipients. Living donation is an alternative in the shortage of cadaveric donors.

  16. Initial thoracic involvement in lymphoma. CT assessment; Afectacion toracica inicial en el linfom. Valoracion con TC

    Energy Technology Data Exchange (ETDEWEB)

    Bustos, A.; Corredoira, J.; Ferreiros, J.; Cabeza, B.; Jorquera, M.; Pedrosa, I.; Martinez, R.; Fernandez, C. [Hospital Clinico San Carlos. Madrid (Spain)

    2002-07-01

    To analyze the initial thoracic involvement by CT in a consecutive series of patients with lymphoma. A retrospective analysis was made of thoracic CT studies made at the time of diagnosis of 259 patients with lymphoma. Mediastinal pulmonary, pleural, pericardial and chest wall involvement was assessed by CT. Of 259 patients (129 men y 130 women), 56 had Hodgkin's disease (HD) and 203 had non-Hodgkin lymphoma (NHL). Forty-two percent (42.5%, 110/259) of the patients had chest involvement on CT: 33 of 56 patients with HD (58.9%) and 77 of 203 patients with NHL (37.9%). All the patients with thoracic HD and 71.4% of patients with thoracic NHL, had mediastinal lymph node involvement. of the patients with thoracic involvement 12.1% (4/33) of the patient with HD and 23.3% (18/77) of the patients with NHL had pulmonary involvement. Thoracic involvement on CT was more frequent in HD. Mediastinal lymph node involvement was the most common finding fundamentally in HD. Pulmonary disease always occurred in the presence of mediastinal lymph node involvement in HD but could occur as an isolated finding in NHL. (Author) 24 refs.

  17. The similar hexheimer reaction during initial treatment of pulmonary tuberculosis: CT appearances

    International Nuclear Information System (INIS)

    Lu Yan; Zhou Xinhua; Xie Ruming; Xu Jinping

    2009-01-01

    Objective: To investigate CT features of similar Hexheimer's reaction during initial treatment of active pulmonary tuberculosis. Methods: The similar Hexheimer's reaction in 44 patients diagnosed by clinic and follow-up CT scans were retrospectively reviewed by three radiologists. Results: During initial treatment of active pulmonary tuberculosis, development of radiographic progression were observed in 57 foci, including 28 pulmonary lesions increased at the site of their original lesion or new opacities elsewhere, ipsilateral or contralateral to the original lesion or both, 10 lesions related to the pleura (pleural effusion, pleural tuberculoma), 15 lymphadenectasis, 3 thymus reactions, and 1 cardiac pericardium thickening, respectively. These reactions appeared from the 20 days to 3.5 months, then with continuation of the initial chemotherapy for 1.0-3.0 months, the radiographic response was excellent with the areas of progression and the original lesions demonstrating resolution or improvement. Conclusion: The CT appearances of similar Hexheimer's reaction during initial treatment of active tuberculosis are specific to a certainty. (authors)

  18. Initial TMX central-cell ICRH experiments

    International Nuclear Information System (INIS)

    Molvik, A.W.; Coffield, F.E.; Falabella, S.; Griffin, D.; McVey, B.; Pickles, W.; P.

    1980-01-01

    Four topics are discussed in this report: the feasibility of applying ion cyclotron resonance heating (ICRH) in the TMX central cell, some applications of heating, the results of preliminary experiments, and plans for further ICRH experiments

  19. Robotic repair of vesicovaginal fistula - initial experience

    Directory of Open Access Journals (Sweden)

    Ankush Jairath

    2016-02-01

    Full Text Available ABSTRACT Objective The most common acquired fistula of the urinary tract is Vesicovaginal fistulae (VVF (1 posing social stigmata for the patient as well as a surgical challenge for the urologist. Here we present our initial experience with Robotic assisted laparoscopic repair of VVF, its safety and efficacy. Materials and Methods Seven out of eight fistulas were post hysterectomy; five had undergone abdominal while two had laparoscopic hysterectomy while one was due to prolonged labour. Two had associated ureteric injury. All underwent robotic assisted laparoscopic trans abdominal extravesical approach. Three 8 mm ports for robotic arms, one 12 mm port for camera and another 12 mm for assistant were used in a fan shaped manner. All had preoperative ureteric catheter placed. Bladder was closed in two layers and vagina in one layer. Omental flap placed in all cases except two where it was not possible. Drain and per urethral catheter placed in all cases. Double J stents were placed in two cases requiring ureteric implantation additionally. Results The mean age of presentation was 39.25 years (26-47 range with mean BMI being 26.25 kg/m2 (21-32 range. Mean duration between insult and repair was 9.37 months (3-24 months. Only in single case there was history of previous repair attempt. On cystoscopy four had supratrigonal VVF and four were trigonal with mean size of 13.37 mm (7-20 mm. Mean operative time was 117.5 minutes (90-150. There were no intraoperative/postoperative complications or need for open conversion. Mean haemoglobin drop was 1.4 gm/dL (0.3-2 gm. Drain was removed once 24-48 hours output is negligible. One patient had post-operative urinary leak at 2 weeks which ceased with continuation of catheterisation for another 2 weeks. Catheter was removed after voiding cystourethrogram showed no leak at 2-3 weeks postoperatively. Mean duration of drain was 3.75 days (3-5 and per urethral catheterisation (which was removed after voiding

  20. Initial Encounters : The Lived Experiences of Buyers

    NARCIS (Netherlands)

    G. Wright; J.J. Dekker

    2012-01-01

    The initial encounter between a buyer and a seller has received much attention among practitioners. The first time a buyer interacts with a seller is thought to be highly influential. The premise is that buyers form an opinion during this first encounter, or even the first minutes of this encounter.

  1. Performance of FDG PET/CT at initial diagnosis in a rare lymphoma: nodular lymphocyte-predominant Hodgkin lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Grellier, Jean Francois; Weinmann, Pierre [AP-HP- Hopital Europeen Georges Pompidou, Service de medecine nucleaire, Paris (France); Vercellino, Laetitia; Merlet, Pascal; Toubert, Marie-Elisabeth; Berenger, Nathalie [AP-HP- Hopital Saint-Louis, Service de medecine nucleaire, Paris (France); Leblanc, Thierry [Hopital Saint-Louis, Service d' immuno-hematologie, Paris (France); Thieblemont, Catherine [Universite Paris Diderot, Sorbonne Paris Cite - INSERM UMR-S1165, AP-HP- Hopital Saint-Louis, Service d' hemato-Oncologie, Paris (France); Briere, Josette [AP-HP- Hopital Saint-Louis, Service de pathologie, Paris (France); Brice, Pauline [AP-HP- Hopital Saint-Louis, Service d' hemato-Oncologie, Paris (France)

    2014-11-15

    Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare Hodgkin lymphoma distinguished from classical Hodgkin lymphoma (cHL) by the nature of the neoplastic cells which express B-cell markers. We wanted to determine the diagnostic performance of FDG PET/CT in initial assessment and its therapeutic impact on staging. We retrospectively studied a population of 35 patients with NLPHL (8 previously treated for NLHPL, 27 untreated). All patients underwent an initial staging by pretherapeutic FDG PET/CT. The impact on initial stage or relapse stage was assessed by an independent physician. In a per-patient analysis, the sensitivity of the pretherapeutic FDG PET/CT was 100 %. In a per-site analysis, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of pretherapeutic FDG PET/CT were 100 %, 99 %, 97 %, 100 % and 99 %, respectively. Pretherapeutic FDG PET/CT led to a change in the initial stage/relapse stage in 12 of the 35 patients (34 %). In contrast to previous results established without FDG PET/CT, 20 % of patient had osteomedullary lesions. Pretherapeutic FDG PET/CT has excellent performance for initial staging or relapse staging of NLPHL. (orig.)

  2. Implementing radiographic CT head reporting: The experiences of students and managers

    International Nuclear Information System (INIS)

    Clarke, Ruth; Allen, David; Arnold, Paul; Snaith, Beverley

    2014-01-01

    Introduction: In the face of growing demand in radiology, skill mix initiatives have sought to improve and expand service provision. Within the UK radiographer reporting is now widespread, although the growth in computerised tomography (CT) head reporting has not been as rapid as anticipated. The literature in this area is limited, but case studies have highlighted the successful implementation of this training through new radiographer roles in practice. Method: A cross-sectional survey was developed to elicit information from radiographers and managers on their experiences before, during and after post-graduate training in CT head reporting. Results: Seventy one responses were received comprising 48 past students (n = 48/111; 43.2%) and 23 service managers (n = 23/67; 34.3%). Key factors for the development were personal continual professional development for students and departmental need for managers. Challenges during training included a lack of study time due to staff shortages and access to radiologist mentors. Only 48.8% of students responding have gone on to use the new skills in practice cited reasons include staff shortages, resistance from radiologists and increase in radiological staffing. Conclusions: This qualitative study has demonstrated that those trusts who have implemented CT head reporting have evidenced perceptible benefits for both the department and individuals. Those radiographers who are successfully reporting have shown themselves to be highly motivated and persistent in their development

  3. Initial performance of the COSINE-100 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Adhikari, G.; Adhikari, P. [Sejong University, Department of Physics, Seoul (Korea, Republic of); Souza, E.B. de; Jo, J.H.; Lim, K.E.; Maruyama, R.H.; Pierpoint, Z.P.; Thompson, W.G. [Yale University, Department of Physics, New Haven, CT (United States); Carlin, N. [University of Sao Paulo, Physics Institute, Sao Paulo (Brazil); Choi, S.; Joo, H.W.; Kim, S.K. [Seoul National University, Department of Physics and Astronomy, Seoul (Korea, Republic of); Choi, W.Q. [Korea Institute of Science and Technology Information, Daejeon (Korea, Republic of); Karlsruher Institut fuer Technologie (KIT), Institut fuer Experimentelle Kernphysik, Eggenstein-Leopoldshafen (Germany); Djamal, M.; Prihtiadi, H. [Bandung Institute of Technology, Department of Physics, Bandung (Indonesia); Ezeribe, A.C.; Kudryavtsev, V.A.; Lynch, W.A.; Mouton, F.; Spooner, N.J.C. [University of Sheffield, Department of Physics and Astronomy, Sheffield (United Kingdom); Ha, C.; Jeon, E.J.; Kang, W.G.; Kim, B.H.; Kim, H.; Kim, K.W.; Kim, N.Y.; Lee, H.S.; Lee, J.; Lee, M.H.; Leonard, D.S.; Olsen, S.L.; Park, H.K.; Park, K.S.; Ra, S.; Yong, S.H. [Institute for Basic Science (IBS), Center for Underground Physics, Daejeon (Korea, Republic of); Hahn, I.S. [Ewha Womans University, Department of Science Education, Seoul (Korea, Republic of); Hubbard, A.J.F. [Yale University, Department of Physics, New Haven, CT (United States); Northwestern University, Department of Physics and Astronomy, Evanston, IL (United States); Kang, W.; Rott, C. [Sungkyunkwan University, Department of Physics, Seoul (Korea, Republic of); Kauer, M. [University of Wisconsin-Madison, Department of Physics and Wisconsin IceCube Particle Astrophysics Center, Madison, WI (United States); Kim, H.J.; Lee, J.Y. [Kyungpook National University, Department of Physics, Daegu (Korea, Republic of); Kim, M.C. [Sungkyunkwan University, Department of Physics, Seoul (Korea, Republic of); Chiba University, Department of Physics, Chiba (Japan); Kim, Y.D. [Sejong University, Department of Physics, Seoul (Korea, Republic of); Institute for Basic Science (IBS), Center for Underground Physics, Daejeon (Korea, Republic of); Kim, Y.H. [Institute for Basic Science (IBS), Center for Underground Physics, Daejeon (Korea, Republic of); Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Park, H.S. [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Park, J.S. [Institute for Basic Science (IBS), Center for Underground Physics, Daejeon (Korea, Republic of); High Energy Accelerator Research Organization (KEK), Ibaraki (Japan); Pettus, W. [Yale University, Department of Physics, New Haven, CT (United States); University of Washington, Department of Physics, Center for Experimental Nuclear Physics and Astrophysics, Seattle, WA (United States); Rogers, F.R. [Yale University, Department of Physics, New Haven, CT (United States); Massachusetts Institute of Technology, Department of Physics, Cambridge, MA (United States); Scarff, A. [University of Sheffield, Department of Physics and Astronomy, Sheffield (United Kingdom); University of British Columbia, Department of Physics and Astronomy, Vancouver, BC (Canada); Yang, L. [University of Illinois at Urbana-Champaign, Department of Physics, Urbana, IL (United States)

    2018-02-15

    COSINE is a dark matter search experiment based on an array of low background NaI(Tl) crystals located at the Yangyang underground laboratory. The assembly of COSINE-100 was completed in the summer of 2016 and the detector is currently collecting physics quality data aimed at reproducing the DAMA/LIBRA experiment that reported an annual modulation signal. Stable operation has been achieved and will continue for at least 2 years. Here, we describe the design of COSINE-100, including the shielding arrangement, the configuration of the NaI(Tl) crystal detection elements, the veto systems, and the associated operational systems, and we show the current performance of the experiment. (orig.)

  4. Initial experiments with Multiple Musical Gestures

    DEFF Research Database (Denmark)

    Jensen, Kristoffer; Graugaard, Lars

    2005-01-01

    The classic orchestra has a diminishing role in society, while hard-disc recorded music plays a predominant role today. A simple to use pointer interface in 2D for producing music is presented as a means for playing in a social situation. The sounds of the music are produced by a low-level...... synthesizer, and the music is produced by simple gestures that are repeated easily. The gestures include left-to-right and right-to-left motion shapes for spectral envelope and temporal envelope of the sounds, with optional backwards motion for the addition of noise; downward motion for note onset and several...... other manipulation gestures. The initial position controls which parameter is being affected, the notes intensity is controlled by the downward gesture speed, and a sequence is finalized instantly with one upward gesture. The synthesis employs a novel interface structure, the multiple musical gesture...

  5. The role of CT-guided percutaneous drainage of loculated air collections: an institutional experience.

    Science.gov (United States)

    Patel, Bhavik N; Morgan, Madeline; Tyler, Douglas; Paulson, Erik; Jaffe, Tracy A

    2015-10-01

    The purpose of this study is to describe our experience with the role of CT-guided percutaneous drainage of loculated intra-abdominal collections consisting entirely of gas. An IRB-approved retrospective study analyzing patients with air-only intra-abdominal collections over an 8-year period was undertaken. Seven patients referred for percutaneous drainage were included. Size of collections, subsequent development of fluid, and microbiological yield were determined. Clinical outcome was also analyzed. Out of 2835 patients referred for percutaneous drainage between 2004 and 2012, seven patients (5M, 2F; average age 63, range 54-85) met criteria for inclusion with CT showing air-only collections. Percutaneous drain placement (five 8 Fr, one 10 Fr, and one 12 Fr) using Seldinger technique was performed. Four patients (57%) had recently undergone surgery (2 Whipple, 1 colectomy, 1 hepatic resection) while two (29%) had a remote surgery (1 abdominoperineal resection, 1 sigmoidectomy). Despite the lack of detectable fluid on the original CT, 6 patients (86%) had air and fluid aspirated at drainage, 5 (83%) of the aspirates developed positive microbacterial cultures. Four patients (57%) presented with fever at the time of the initial scan, all of whom had positive cultures from aspirated fluid. Four patients (57%) had leukocytosis, all of whom had positive cultures from aspirated fluid. Although relatively rare in occurrence, patients with air-only intra-abdominal collections with signs of infection should be considered for percutaneous management similar to that of conventional infected fluid collections. Although fluid is not visible on CT, these collections can produce fluid that contains organisms.

  6. SISCOM imaging : an initial South African experience

    International Nuclear Information System (INIS)

    Warwick, J.; Rubow, S.; Van Heerden, B.; Ghoorun, S.; Butler, J.

    2004-01-01

    Full text: Subtraction ictal SPECT co-registered with MRI (SISCOM) is a new technique utilized for the detection and localization of epileptogenic foci in patients with refractory focal epilepsy who are candidates for surgical resection. The technique requires many challenges to be overcome, in particular in relation to the administration of the radiopharmaceutical, acquisition of brain SPECT and the conversion, co-registration and fusion of brain SPECT and MRI studies. Furthermore the interpretation of the studies is complex and is ideally performed in a multidisciplinary context in cooperation with disciplines such as neurology, radiology, psychiatry and neurosurgery. Materials and methods: Two brain SPECT studies are performed using 99m Tc-ethylene cystinate dimer (ECD). An ictal study is performed after the administration of the 99m Tc-ECD during a seizure. An interictal SPECT, performed between seizures is then subtracted from the ictal SPECT, and the difference image fused with an MRI study to optimise localization of the epileptogenic focus. Image conversion, co-registration and fusion was performed using MRlcro and SPM software. Results: To date the Departments of Neurology and Nuclear Medicine have completed over 10 SISCOM studies. Conclusion: During this presentation this initial work will be presented. The methodology as well as the challenges involved in performing and interpreting these studies will be discussed. Individual cases will be used to illustrate the impact of this powerful technique on future patient management. (author)

  7. Association of initial CT findings with quality-of-life outcomes for traumatic brain injury in children

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, Jonathan O. [Seattle Children' s Hospital and University of Washington, Department of Radiology, Seattle, WA (United States); Vavilala, Monica S.; Wang, Jin; Rivara, Frederick P. [Harborview Medical Center, University of Washington, Department of Pediatrics, Seattle, WA (United States); Pruthi, Sumit [Monroe Carell Jr. Children' s Hospital at Vanderbilt University, Department of Radiology, Nashville, TN (United States); Fink, James [University of Washington, Department of Radiology, Seattle, WA (United States); Jaffe, Kenneth M. [University of Washington, Department of Rehabilitation Medicine, Seattle, WA (United States); Durbin, Dennis [University of Pennsylvania, Department of Pediatrics, Center for Injury Research and Prevention, The Children' s Hospital of Philadelphia, Philadelphia, PA (United States); Koepsell, Thomas [University of Washington, Department of Epidemiology, Seattle, WA (United States); Temkin, Nancy [University of Washington, Biostatistics, Seattle, WA (United States)

    2012-08-15

    Traumatic brain injury (TBI) is a leading cause of acquired disability in children and adolescents. To demonstrate the association between specific findings on initial noncontrast head CT and long-term outcomes in children who have suffered TBI. This was an IRB-approved prospective study of children ages 2-17 years treated in emergency departments for TBI and who underwent a head CT as part of the initial work-up (n = 347). The change in quality of life at 12 months after injury was measured by the PedsQL scale. Children with TBI who had intracranial injuries identified on the initial head CT had a significantly lower quality-of-life scores compared to children with TBI whose initial head CTs were normal. In multivariate analysis, children whose initial head CT scans demonstrated intraventricular hemorrhage, parenchymal injury, midline shift {>=}5 mm, hemorrhagic shear injury, abnormal cisterns or subdural hematomas {>=}3 mm had lower quality of life scores 1 year after injury than children whose initial CTs did not have these same injuries. Associations exist between findings from the initial noncontrast head CT and quality of life score 12 months after injury in children with TBI. (orig.)

  8. Initial Educational Experiences of Tertiary Students. LSAY Briefing Number 14

    Science.gov (United States)

    Hillman, Kylie

    2008-01-01

    This "Briefing" presents information about the initial tertiary education experiences, such as satisfaction with aspects of student life and changes to initial enrolments, of two groups of young people, based on two recent Longitudinal Surveys of Australian Youth (LSAY) research reports. One study focused on the first year experiences of…

  9. Laparoscopic nephrectomy: initial experience with 120 cases.

    LENUS (Irish Health Repository)

    Cheema, I A

    2012-02-01

    Laparoscopic nephrectomy for both benign and malignant diseases of kidney is increasingly being performed. We report our experience with the first 120 consecutive laparoscopic nephrectomy performed in our hospital. It is the retrospective analysis of a prospectively maintained database of 4 years period. The parameters examined included age, gender, indications, operative time, blood loss, intraoperative and post operative complications. Mean age of surgery was 59 years (rang 19-84years). The indications for surgery included solid renal masses (71 patients), non-functioning kidneys (43), and collecting system tumours (6). The mean operating time was 132 minutes (range 75-270), average blood loss was 209 ml (range 0-1090) and average hospital stay was 4.7days (range 2-20). Bleeding, bowel injury and poor progression of laparoscopic procedure were the reasons in 7 (5.8%) cases converted to open surgery. There was 1 (0.8%) perioperative mortality. Eight (6.6%) patients developed post operative complications. Laparoscopic nephrectomy has inherent benefits and may be considered an alternate therapeutic option for kidney diseases with acceptable morbidity

  10. Laparoscopic nephrectomy: initial experience with 120 cases.

    LENUS (Irish Health Repository)

    Cheema, I A

    2010-02-01

    Laparoscopic nephrectomy for both benign and malignant diseases of kidney is increasingly being performed. We report our experience with the first 120 consecutive laparoscopic nephrectomy performed in our hospital. It is the retrospective analysis of a prospectively maintained database of 4 years period. The parameters examined included age, gender, indications, operative time, blood loss, intraoperative and post operative complications. Mean age of surgery was 59 years (rang 19-84years). The indications for surgery included solid renal masses (71 patients), non-functioning kidneys (43), and collecting system tumours (6). The mean operating time was 132 minutes (range 75-270), average blood loss was 209 ml (range 0-1090) and average hospital stay was 4.7days (range 2-20). Bleeding, bowel injury and poor progression of laparoscopic procedure were the reasons in 7 (5.8%) cases converted to open surgery. There was 1 (0.8%) perioperative mortality. Eight (6.6%) patients developed post operative complications. Laparoscopic nephrectomy has inherent benefits and may be considered an alternate therapeutic option for kidney diseases with acceptable morbidity

  11. Initial performance of the CUORE-0 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Artusa, D.R. [University of South Carolina, Department of Physics and Astronomy, Columbia, SC (United States); INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); Avignone, F.T.; Chott, N.; Creswick, R.J.; Farach, H.A.; Rosenfeld, C.; Wilson, J. [University of South Carolina, Department of Physics and Astronomy, Columbia, SC (United States); Azzolini, O.; Keppel, G.; Palmieri, V. [INFN-Laboratori Nazionali di Legnaro, Padua (Italy); Balata, M.; Bucci, C.; Canonica, L.; Casali, N.; Di Vacri, M.L.; Goett, J.; Gorla, P.; Nisi, S.; Orlandi, D.; Pattavina, L.; Pirro, S.; Zarra, C. [INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); Banks, T.I. [INFN-Laboratori Nazionali del Gran Sasso, L' Aquila (Italy); University of California, Department of Physics, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Bari, G.; Deninno, M.M.; Moggi, N. [INFN-Sezione di Bologna, Bologna (Italy); Beeman, J. [Lawrence Berkeley National Laboratory, Materials Science Division, Berkeley, CA (United States); Bellini, F.; Cardani, L.; Cosmelli, C.; Ferroni, F.; Piperno, G. [Sapienza Universita di Roma, Dipartimento di Fisica, Rome (Italy); INFN-Sezione di Roma, Rome (Italy); Bersani, A. [INFN-Sezione di Genova, Genoa (Italy); Biassoni, M.; Brofferio, C.; Capelli, S.; Carrettoni, M.; Chiesa, D.; Clemenza, M.; Faverzani, M.; Ferri, E.; Fiorini, E.; Giachero, A.; Gironi, L.; Gotti, C.; Maiano, C.; Maino, M.; Nucciotti, A.; Pavan, M.; Sala, E.; Sisti, M.; Terranova, F.; Zanotti, L. [Universita di Milano-Bicocca, Dipartimento di Fisica, Milan (Italy); INFN-Sezione di Milano Bicocca, Milan (Italy); Cai, X.Z.; Cao, X.G.; Fang, D.Q.; Li, Y.L.; Ma, Y.G.; Tian, W.D.; Wang, H.W. [Shanghai Institute of Applied Physics (Chinese Academy of Sciences), Shanghai (China); Carbone, L.; Cremonesi, O.; Datskov, V.; Pessina, G.; Previtali, E.; Rusconi, C. [INFN-Sezione di Milano Bicocca, Milan (Italy); Dafinei, I.; Morganti, S.; Orio, F.; Pettinacci, V.; Tomei, C.; Vignati, M. [INFN-Sezione di Roma, Rome (Italy); Dally, A.; Ejzak, L.; Wielgus, L. [University of Wisconsin, Department of Physics, Madison, WI (United States); Di Domizio, S.; Fernandes, G.; Pallavicini, M. [INFN-Sezione di Genova, Genoa (Italy); Universita di Genova, Dipartimento di Fisica, Genoa (Italy); Freedman, S.J. [University of California, Department of Physics, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Fujikawa, B.K.; Han, K.; Mei, Y. [Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Giuliani, A.; Tenconi, M. [Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, Orsay Campus (France); Gutierrez, T.D. [California Polytechnic State University, Physics Department, San Luis Obispo, CA (United States); Haller, E.E. [Lawrence Berkeley National Laboratory, Materials Science Division, Berkeley, CA (United States); University of California, Department of Materials Science and Engineering, Berkeley, CA (United States); Heeger, K.M.; Lim, K.E.; Maruyama, R.H. [Yale University, Department of Physics, New Haven, CT (United States); Hennings-Yeomans, R.; Ouellet, J.L. [University of California, Department of Physics, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Huang, H.Z.; Liu, X.; Trentalange, S.; Winslow, L.A.; Zhu, B.X. [University of California, Department of Physics and Astronomy, Los Angeles, CA (United States); Kadel, R. [Lawrence Berkeley National Laboratory, Physics Division, Berkeley, CA (United States); Kazkaz, K.; Pedretti, M.; Sangiorgio, S.; Scielzo, N.D. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Kolomensky, Yu.G. [University of California, Department of Physics, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Physics Division, Berkeley, CA (United States); Martinez, M. [Universidad de Zaragoza, Laboratorio de Fisica Nuclear y Astroparticulas, Saragossa (Spain); Nones, C. [Service de Physique des Particules, CEA/Saclay, Gif-sur-Yvette (France); Norman, E.B.; Wang, B.S. [Lawrence Livermore National Laboratory, Livermore, CA (United States); University of California, Department of Nuclear Engineering, Berkeley, CA (United States); O' Donnell, T. [University of California, Department of Physics, Berkeley, CA (United States); Smith, A.R. [Lawrence Berkeley National Laboratory, EH and S Division, Berkeley, CA (United States); Taffarello, L. [INFN-Sezione di Padova, Padua (Italy); Ventura, G. [Universita di Firenze, Dipartimento di Fisica, Florence (Italy); INFN-Sezione di Firenze, Florence (Italy); Wise, T. [University of Wisconsin, Department of Physics, Madison, WI (United States); Yale University, Department of Physics, New Haven, CT (United States); Zucchelli, S. [INFN-Sezione di Bologna, Bologna (Italy); Universita di Bologna, Dipartimento di Fisica, Bologna (Italy)

    2014-08-15

    CUORE-0 is a cryogenic detector that uses an array of tellurium dioxide bolometers to search for neutrinoless double-beta decay of {sup 130}Te. We present the first data analysis with 7.1kg . y of total TeO{sub 2} exposure focusing on background measurements and energy resolution. The background rates in the neutrinoless double-beta decay region of interest (2.47 to 2.57MeV) and in the α backgrounddominated region (2.70 to 3.90 MeV) have been measured to be 0.071 ± 0.011 and 0.019 ± 0.002 counts/(keV . kg . y), respectively. The latter result represents a factor of 6 improvement from a predecessor experiment, Cuoricino. The results verify our understanding of the background sources in CUORE-0, which is the basis of extrapolations to the full CUORE detector. The obtained energy resolution (full width at half maximum) in the region of interest is 5.7 keV. Based on themeasured background rate and energy resolution in the region of interest, CUORE-0 half-life sensitivity is expected to surpass the observed lower bound of Cuoricino with one year of live time. (orig.)

  12. VIM: Initial ENDF/B-VI experience

    International Nuclear Information System (INIS)

    Blomquist, R.N.

    1997-01-01

    The VIM Monte Carlo particle transport code uses detailed continuous-energy cross sections produced from ENDF/B data by a set of specialized codes developed or adapted for use at Argonne National Laboratory. ENDF/B-IV data were used until about 1979, and Version V data since then. These VIM libraries were extensively benchmarked against the MC 2 -2 code and against ZPR and ZPPR criticals for fast spectrum calculations, as well as other fast and thermal experiments and calculations. Recently, the cross section processing codes have been upgraded to accommodate ENDF/B-VI files, and a small library has been tested. Several fundamental tasks comprise the construction of a faithful representation of ENDF data for VIM calculations: (1) The resolved resonance parameters are converted to Doppler-broadened continuous-energy cross sections with energy grids suitable for linear-linear interpolation. (2) The unresolved resonance parameter distributions are sampled to produce many (40-400) resonance ladders in each energy band. These are converted to Doppler-broadened continuous energy resonance cross sections that are then binned by cross section, accumulating ladders until statistical convergence, the result being probability tables of total cross sections and conditional mean scattering and fission cross sections. VIM samples these tables at run time, and File 3 back ground cross sections are added. (3) Anisotropic angular distribution data are converted to angular probability tables. All other ENDF data are unmodified, except for format

  13. Five Years of Cyclotron Radioisotope Production Experiences at the First PET-CT in Venezuela

    International Nuclear Information System (INIS)

    Colmenter, L.; Coelho, D.; Esteves, L. M.; Ruiz, N.; Morales, L.; Lugo, I.; Sajo-Bohus, L.; Liendo, J. A.; Greaves, E. D.; Barros, H.; Castillo, J.

    2007-01-01

    Five years operation of a compact cyclotron installed at PET-CT facility in Caracas, Venezuela is given. Production rate of 18 F labeled FDG, operation and radiation monitoring experience are included. We conclude that 18 FDG CT-PET is the most effective technique for patient diagnosis

  14. Perfusion CT in childhood stroke—Initial observations and review of the literature

    Energy Technology Data Exchange (ETDEWEB)

    Zebedin, D., E-mail: doris.zebedin@medunigraz.at [Division of Pediatric Radiology, Department of Radiology, University Hospital LKH Graz (Austria); Sorantin, E.; Riccabona, M. [Division of Pediatric Radiology, Department of Radiology, University Hospital LKH Graz (Austria)

    2013-07-15

    Introduction: To report the preliminary results of contrast-enhanced perfusion multi-detector CT for diagnoses of perfusion disturbances in children with clinical suspicion of stroke. Patients and methods: Within the last two years emergency perfusion CT was performed in ten children (age: 8–17 years, male:female = 3:7) for assessment of suspected childhood stroke. These intracranial perfusion CT, intracranial CT-digital subtraction angiography (CT-DSA) and extracranial CT-angiography (CTA) studies were retrospectively reviewed and compared with MRI, follow-up CT, catheter angiography and final clinical diagnosis. The total dose length product (DLP) for the entire examination was recorded. The image quality of perfusion CT-maps, CT-DSA and CTA were evaluated with a subjective three-point scale ranging from very good to non-diagnostic image quality rating perfusion disturbance, intracranial peripheral vessel depiction, and motion- or streak artifacts. Results: In nine of ten children perfusion CT showed no false positive or false negative results. In one of ten children suffering from migraine focal hypo-perfusion was read as perfusion impairment potentially indicating early stroke, but MRI and MRA follow-up were negative. Overall, perfusion-CT with CT-DSA was rated very good in 80% of cases for the detection of perfusion disturbances and vessel anatomy. Conclusions: In comparison to standard CT, contrast-enhanced perfusion CT improves CTs’ diagnostic capability in the emergency examination of children with a strong suspicion of ischemic cerebral infarction.

  15. Initially curved microplates under electrostatic actuation: theory and experiment

    KAUST Repository

    Saghir, Shahid; Bellaredj, Mohammed Lamine Faycal; Ramini, Abdallah; Younis, Mohammad I.

    2016-01-01

    Microplates are the building blocks of many micro-electro-mechanical systems. It is common for them to experience initial curvature imperfection due to residual stresses caused by the micro fabrication process. Such plates are essentially different

  16. Early experiences with crowdsourcing airway annotations in chest CT

    DEFF Research Database (Denmark)

    Cheplygina, Veronika; Perez-Rovira, Adria; Kuo, Wieying

    2016-01-01

    Measuring airways in chest computed tomography (CT) images is important for characterizing diseases such as cystic fibrosis, yet very time-consuming to perform manually. Machine learning algorithms offer an alternative, but need large sets of annotated data to perform well. We investigate whether...... a number of further research directions and provide insight into the challenges of crowdsourcing in medical images from the perspective of first-time users....

  17. Quality control in PET/CT systems. Experiences and requirements

    International Nuclear Information System (INIS)

    Geworski, Lilli; Fitz, Eduard; Knoop, Bernd; Karwarth, Cornelia; Plotkin, Michail

    2010-01-01

    Today, in most cases PET examinations are performed using PET/CT hybrid systems. While acceptance testing and routine control of the basic modalities PET and CT, respectively, are described by appropriate regulations, corresponding instructions with regard to the interface connecting both are still missing. This interface includes the adjustment of gantries and patient bed to each other as well as the energy scaling of attenuation coefficients from CT energy to 511 keV. Measurements checking the mechanical adjustment (determination of off-set parameters) are performed following manufacturer's recommendation, with a typical frequency twice a year. On a Biograph 16 (Siemens, Inc.), these measurements were systematically extended to a weekly frequency over an observation period of 10 months, supplemented by measurements with additional load to the patient bed (up to 135 kg), and different vertical bed positions. The results show, that for the construction tested additional off-set measurements for routine control extending well beyond manufacturer's recommendation are not necessary. The energy scaling of attenuation coefficients is depending on methodological aspects and software implementation, and therefore is not part of routine control. On the contrary, the development of appropriate methods for acceptance testing to assess and to determine the mechanical adjustment in all its degrees of freedom as well as the accuracy of attenuation corrected emission data is urgently needed. (orig.)

  18. Multicenter Comparison of Contrast-Enhanced FDG PET/CT and 64-Slice Multi-Detector-Row CT for Initial Staging and Response Evaluation at the End of Treatment in Patients With Lymphoma.

    Science.gov (United States)

    Gómez León, Nieves; Delgado-Bolton, Roberto C; Del Campo Del Val, Lourdes; Cabezas, Beatriz; Arranz, Reyes; García, Marta; Cannata, Jimena; González Ortega, Saturnino; Pérez Sáez, Mª Ángeles; López-Botet, Begoña; Rodríguez-Vigil, Beatriz; Mateo, Marta; Colletti, Patrick M; Rubello, Domenico; Carreras, José L

    2017-08-01

    To compare staging correctness between contrast-enhanced FDG PET/ceCT and 64-slice multi-detector-row CT (ceCT64) for initial staging and response evaluation at the end of treatment (EOT) in patients with Hodgkin lymphoma, diffuse large B cell lymphoma (DLBCL), and follicular lymphoma. This prospective study compared initial staging and response evaluation at EOT. One hundred eighty-one patients were randomly assigned to either ceCT64 or FDG PET/ceCT. A nuclear medicine physician and a radiologist read FDG PET/ceCT scans independently and achieved post hoc consensus, whereas another independent radiologist interpreted ceCT64 separately. The reference standard included all clinical information, all tests, and follow-up. Ethics committees of the participating centers approved the study, and all participants provided written consent. Ninety-one patients were randomized to ceCT64 and 90 to FDG PET/ceCT; 72 had Hodgkin lymphoma, 72 had DLBCL, and 37 had follicular lymphoma. There was excellent correlation between the reference standard and initial staging for both FDG PET/ceCT (κ = 0.96) and ceCT64 (κ = 0.84), although evaluation of the response at EOT was excellent only for FDG PET/ceCT (κ = 0.91). Our study demonstrated satisfactory agreement between FDG PET/ceCT (κ = 0.96) and ceCT64 (κ = 0.84) in initial staging compared with the reference standard (P = 0.16). Response evaluation at EOT with FDG PET/ceCT (κ = 0.91) was superior compared with ceCT64 (κ = 0.307) (P < 0.001).

  19. Initial Results from Coaxial Helicity Injection Experiments in NSTX

    International Nuclear Information System (INIS)

    Raman, R.; Jarboe, T.R.; Mueller, D.; Schaffer, M.J.; Maqueda, R.; Nelson, B.A.; Sabbagh, S.; Bell, M.; Ewig, R.; Fredrickson, E.; Gates, D.; Hosea, J.; Ji, H.; Kaita, R.; Kaye, S.M.; Kugel, H.; Maingi, R.; Menard, J.; Ono, M.; Orvis, D.; Paolette, F.; Paul, S.; Peng, M.; Skinner, C.H.; Wilgen, W.; Zweben, S.

    2001-01-01

    Coaxial Helicity Injection (CHI) has been investigated on the National Spherical Torus Experiment (NSTX). Initial experiments produced 130 kA of toroidal current without the use of the central solenoid. The corresponding injector current was 20 kA. Discharges with pulse lengths up to 130 ms have been produced

  20. PET/CT versus bone marrow biopsy in the initial evaluation of bone marrow infiltration in various pediatric malignancies.

    Science.gov (United States)

    Zapata, Claudia P; Cuglievan, Branko; Zapata, Catalina M; Olavarrieta, Raquel; Raskin, Scott; Desai, Kavita; De Angulo, Guillermo

    2018-02-01

    Accurate staging is essential in the prognosis and management of pediatric malignancies. Current protocols require screening for marrow infiltration with bone marrow biopsy (BMB) as the gold standard. Positron emission tomography-computed tomography (PET-CT) is commonly used to complete the staging process and can also be used to evaluate marrow infiltration. To compare PET-CT and BMB in the initial evaluation of bone marrow infiltration in pediatric cancers. We retrospectively reviewed new cases of EWS, rhabdomyosarcoma, neuroblastoma, and lymphoma diagnosed between January 2009 and October 2014. Each case had undergone both PET-CT and BMB within 4 weeks without treatment in the interval between screening modalities. We reviewed 69 cases. Bone marrow infiltration was demonstrated in 34 cases by PET-CT and in 18 cases by BMB. The sensitivity and negative predictive value of PET-CT were both 100%. Interestingly, the cases in which infiltration was not detected on BMB had an abnormal marrow signal on PET-CT focal or distant to iliac crest. PET-CT has a high sensitivity when assessing marrow infiltration in pediatric malignancies. Advances in radiologic modalities may obviate the use of invasive, painful, and costly procedures like BMB. Furthermore, biopsy results are limited by insufficient tissue or the degree of marrow infiltration (diffuse vs. focal disease). PET-CT can improve the precision of biopsy when used as a guiding tool. This study proposes the use of PET-CT as first-line screening for bone marrow infiltration to improve the accuracy of staging in new diagnoses. © 2017 Wiley Periodicals, Inc.

  1. Our experience in using the whole body computed tomography unit (GE CT/T)

    International Nuclear Information System (INIS)

    Murakawa, Yasuhiro; Morimoto, Mitsuo; Ishigaki, Naoya; Zaitsu, Hiroaki; Kawabata, Kohji

    1983-01-01

    Since our hospital installed the CT unit of the head and neck (SCT-100N) in April, 1979, we reported our experience in using this equipment in 1980 and 1982. After that, since the whole body CT unit (GE CT/T) was installed in our hospital in April, 1982, the total number of CT examination have reached approximately three thousand five handred till this August. Consequently, this CT image seemed to be superior in image quality to that obtained by other CT equipment. The most important characteristic of this equipment is that the retrospective and prospective reviews of the target image and the coronal and sagittal recontruction from contiguous transverse axial scans are possible. We show in this report two experimental CT photograms obtained by the reviews of the target image in using of microchart phantom and CT photograms of uterus myoma, metastatic thyroid and liver cancers and further, of contiguous transverse axial scans of cerebral embolism and the coronal recontruction. The important problems for the future of this equipment are those of absorbed X-ray dose of the patients and the scan time. (author)

  2. CT urography of urinary diversions with enhanced CT digital radiography: preliminary experience.

    Science.gov (United States)

    Sudakoff, Gary S; Guralnick, Michael; Langenstroer, Peter; Foley, W Dennis; Cihlar, Krista L; Shakespear, Jonathan S; See, William A

    2005-01-01

    The purpose of this study was to determine if 3D-rendered CT urography (CTU) depicts both normal and abnormal findings in patients with urinary diversions and if the addition of contrast-enhanced CT digital radiography (CTDR) improves opacification of the urinary collecting system. Thirty CTU and contrast-enhanced CTDR examinations were performed in 24 patients who underwent cystectomy for bladder cancer. Indications for evaluation included hematuria, tumor surveillance, or suspected diversion malfunction. All examinations were evaluated without knowledge of the stage or grade of a patient's tumor and were compared with the clinical records. Opacification of the urinary collecting system was evaluated with 3D CTU alone, contrast-enhanced CTDR alone, and combined CTU and CTDR. Nine abnormalities were identified including distal ureteral strictures (n = 4), vascular compression of the mid left ureter (n = 1), scarring of the mid right pole infundibulum (n = 1), bilateral hydronephrosis and hydroureter (n = 1), urinary reservoir calculus (n = 1), and tumor recurrence invading the afferent limb of the neobladder (n = 1). Eight of the nine detected abnormalities were surgically or pathologically confirmed. All abnormalities were identified on all three imaging techniques but were best seen on 3D CTU and enhanced CTDR images. Incomplete opacification of the urinary collecting system occurred in 17 patients with CTU alone, 12 patients with contrast-enhanced CTDR alone, and nine patients with combined CTU and contrast-enhanced CTDR. Compared with CTU alone, the combined technique of 3D CTU and contrast-enhanced CTDR improved opacification by a statistically significant difference (p = 0.037). CTU with 3D rendering can accurately depict both normal and abnormal postoperative findings in patients with urinary diversions. Adding enhanced CTDR can improve visualization of the urinary collecting system.

  3. Primary Hepatosplenic B-cell Lymphoma: Initial Diagnosis and Assessment of Therapeutic Response with F-18 FDG PET/CT

    International Nuclear Information System (INIS)

    Kang, Sung Min; Lee, Hong Je; Seo, Ji Hyoung; Lee, Sang Woo; Ahn, Byeong Cheol; Lee, Jae Tae

    2008-01-01

    A 52-year-old woman with a history of general weakness, fatigue, weight loss, elevated serum levels of liver transaminase enzyme for three months underwent an F-18 FDG PET/CT to evaluate a cause of the hepatosplenomegaly found on abdominal ultrasonography. Initial PET/CT revealed markedly enlarged liver and spleen with intense FDG uptake. Otherwise, there were no areas of abnormal FDG uptake in whole body image. Histological evaluation by a hepatic needle biopsy demonstrated diffuse large B cell type lymphoma and final diagnosis for this patient was hepatosplenic B-cell lymphoma. She received five cycles of CHOP chemotherapy, and second PET/CT was followed after then. Follow-up PET-CT revealed normal sized liver with disappearance of abnormal FDG uptake. Hepatosplenic B-cell lymphoma is relatively rare and mostly presents as single or multiple nodules. Diffuse type hepatosplenic lymphoma is extremely rare and poorly recognized entity. The diagnosis is very difficult and complicated by the presence of misleading symptoms.4 In this rare hepatosplenic B-cell lymphoma case, F-18 FDG PET/CT provided a initial diagnostic clue of hepatosplenic lymphoma and an accurate chemotherapy response

  4. Primary Hepatosplenic B-cell Lymphoma: Initial Diagnosis and Assessment of Therapeutic Response with F-18 FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sung Min; Lee, Hong Je; Seo, Ji Hyoung; Lee, Sang Woo; Ahn, Byeong Cheol; Lee, Jae Tae [Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2008-08-15

    A 52-year-old woman with a history of general weakness, fatigue, weight loss, elevated serum levels of liver transaminase enzyme for three months underwent an F-18 FDG PET/CT to evaluate a cause of the hepatosplenomegaly found on abdominal ultrasonography. Initial PET/CT revealed markedly enlarged liver and spleen with intense FDG uptake. Otherwise, there were no areas of abnormal FDG uptake in whole body image. Histological evaluation by a hepatic needle biopsy demonstrated diffuse large B cell type lymphoma and final diagnosis for this patient was hepatosplenic B-cell lymphoma. She received five cycles of CHOP chemotherapy, and second PET/CT was followed after then. Follow-up PET-CT revealed normal sized liver with disappearance of abnormal FDG uptake. Hepatosplenic B-cell lymphoma is relatively rare and mostly presents as single or multiple nodules. Diffuse type hepatosplenic lymphoma is extremely rare and poorly recognized entity. The diagnosis is very difficult and complicated by the presence of misleading symptoms.4 In this rare hepatosplenic B-cell lymphoma case, F-18 FDG PET/CT provided a initial diagnostic clue of hepatosplenic lymphoma and an accurate chemotherapy response.

  5. 18F-FDG PET/CT in breast cancer: Evidence-based recommendations in initial staging.

    Science.gov (United States)

    Caresia Aroztegui, Ana Paula; García Vicente, Ana María; Alvarez Ruiz, Soledad; Delgado Bolton, Roberto Carlos; Orcajo Rincon, Javier; Garcia Garzon, Jose Ramon; de Arcocha Torres, Maria; Garcia-Velloso, Maria Jose

    2017-10-01

    Current guidelines do not systematically recommend 18F-FDG PET/CT for breast cancer staging; and the recommendations and level of evidence supporting its use in different groups of patients vary among guidelines. This review summarizes the evidence about the role of 18F-FDG PET/CT in breast cancer staging and the therapeutic and prognostic impact accumulated in the last decade. Other related aspects, such as the association of metabolic information with biology and prognosis are considered and evidence-based recommendations for the use of 18F-FDG PET/CT in breast cancer staging are offered. We systematically searched MEDLINE for articles reporting studies with at least 30 patients related to clinical questions following the Problem/Population, Intervention, Comparison, and Outcome framework. We critically reviewed the selected articles and elaborated evidence tables structuring the summarized information into methodology, results, and limitations. The level of evidence and the grades of recommendation for the use of 18F-FDG PET/CT in different contexts are summarized. Level III evidence supports the use of 18F-FDG PET/CT for initial staging in patients with recently diagnosed breast cancer; the diagnostic and therapeutic impact of the 18F-FDG PET/CT findings is sufficient for a weak recommendation in this population. In patients with locally advanced breast cancer, level II evidence supports the use of 18F-FDG PET/CT for initial staging; the diagnostic and therapeutic impact of the 18F-FDG PET/CT findings is sufficient for a strong recommendation in this population. In patients with recently diagnosed breast cancer, the metabolic information from baseline 18F-FDG PET/CT is associated with tumor biology and has prognostic implications, supported by level II evidence. In conclusion, 18F-FDG PET/CT is not recommended for staging all patients with early breast cancer, although evidence of improved regional and systemic staging supports its use in locally advanced

  6. Blind CT image quality assessment via deep learning strategy: initial study

    Science.gov (United States)

    Li, Sui; He, Ji; Wang, Yongbo; Liao, Yuting; Zeng, Dong; Bian, Zhaoying; Ma, Jianhua

    2018-03-01

    Computed Tomography (CT) is one of the most important medical imaging modality. CT images can be used to assist in the detection and diagnosis of lesions and to facilitate follow-up treatment. However, CT images are vulnerable to noise. Actually, there are two major source intrinsically causing the CT data noise, i.e., the X-ray photo statistics and the electronic noise background. Therefore, it is necessary to doing image quality assessment (IQA) in CT imaging before diagnosis and treatment. Most of existing CT images IQA methods are based on human observer study. However, these methods are impractical in clinical for their complex and time-consuming. In this paper, we presented a blind CT image quality assessment via deep learning strategy. A database of 1500 CT images is constructed, containing 300 high-quality images and 1200 corresponding noisy images. Specifically, the high-quality images were used to simulate the corresponding noisy images at four different doses. Then, the images are scored by the experienced radiologists by the following attributes: image noise, artifacts, edge and structure, overall image quality, and tumor size and boundary estimation with five-point scale. We trained a network for learning the non-liner map from CT images to subjective evaluation scores. Then, we load the pre-trained model to yield predicted score from the test image. To demonstrate the performance of the deep learning network in IQA, correlation coefficients: Pearson Linear Correlation Coefficient (PLCC) and Spearman Rank Order Correlation Coefficient (SROCC) are utilized. And the experimental result demonstrate that the presented deep learning based IQA strategy can be used in the CT image quality assessment.

  7. British Isles Field Experience: An Initiative in International Education.

    Science.gov (United States)

    Martin, William J.

    The British Isles Field Experience (BIFE) program was initiated at Williamsport Area Community College (WACC) to provide a group of WACC faculty and staff members with individual and group activities of a personal, professional, and cultural nature in order to promote an international perspective that can be infused into student, collegiate, and…

  8. Clinical utility of F-18 FDG PET-CT in the initial evaluation of lung cancer

    DEFF Research Database (Denmark)

    Madsen, Poul Henning; Holdgaard, Paw Christian; Buck Christensen, Janne

    2016-01-01

    the predefined criteria and were read in full to identify relevant original articles on F-18 FDG PET-CT (1) in the evaluation of solitary pulmonary nodules (n = 14), (2) in curative-intent treatment trials (n = 9), and (3) in planning of invasive procedures (n = 18). RESULTS: We found the following important...... results from the literature review: 1) PET-CT can rule out malignancy in most solitary pulmonary nodules due to high sensitivity (recommendation level A). 2) PET-CT reduces the number of futile treatment trials (recommendation level A). 3) The sensitivity of PET-CT in general is insufficient to rule out...... by CT in a structured programme. 2) No curative-intent treatment should be commenced until a PET-CT scan has excluded occult distant metastases. 3) In general, lymph node metastasis in the mediastinum cannot be ruled out on the basis of a negative PET-CT, and confirmative invasive staging should...

  9. Clinical utility of F-18 FDG PET-CT in the initial evaluation of lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Madsen, Poul Henning [Vejle Hospital, Department of Medicine, Division of Respiratory Medicine, Vejle (Denmark); Holdgaard, Paw Christian [Vejle Hospital, Department of Nuclear Medicine, Vejle (Denmark); Christensen, Janne Buck [Odense University Hospital/University of Southern Denmark, Department of Quality and Research/HTA, Odense University Hospital and Medical Research Library, Odense (Denmark); Hoeilund-Carlsen, Poul Flemming [Odense University Hospital, Department of Nuclear Medicine, Odense (Denmark)

    2016-10-15

    Positron emission tomography-computed tomography (PET-CT) is a resource-demanding imaging modality with increasing popularity in the workup of patients with suspected or proven lung cancer. To review the clinical usefulness of this imaging modality in the diagnosis, staging, and pre-operative evaluation, we conducted a systematic literature search, review, and quality assessment using the rapid evidence assessment toolkit and the Oxford Centre for Evidence-Based Medicine methodology. The literature search resulted in 4,208 records including 918 reviews, of which 139 met the predefined criteria and were read in full to identify relevant original articles on F-18 FDG PET-CT (1) in the evaluation of solitary pulmonary nodules (n = 14), (2) in curative-intent treatment trials (n = 9), and (3) in planning of invasive procedures (n = 18). We found the following important results from the literature review: (1) PET-CT can rule out malignancy in most solitary pulmonary nodules due to high sensitivity (recommendation level A). (2) PET-CT reduces the number of futile treatment trials (recommendation level A). (3) The sensitivity of PET-CT in general is insufficient to rule out mediastinal lymph node metastasis (recommendation level A). (1) With few exceptions, solitary pulmonary nodules can safely be considered benign if the PET-CT scan is negative. Exceptions consist of small (<1 cm) and non-solid, solitary pulmonary nodules. These abnormalities should be followed up by CT in a structured programme. (2) No curative-intent treatment should be commenced until a PET-CT scan has excluded occult distant metastases. (3) In general, lymph node metastasis in the mediastinum cannot be ruled out on the basis of a negative PET-CT, and confirmative invasive staging should be performed in most patients before mediastinal metastasis is confirmed or ruled out. (orig.)

  10. Clinical utility of F-18 FDG PET-CT in the initial evaluation of lung cancer

    International Nuclear Information System (INIS)

    Madsen, Poul Henning; Holdgaard, Paw Christian; Christensen, Janne Buck; Hoeilund-Carlsen, Poul Flemming

    2016-01-01

    Positron emission tomography-computed tomography (PET-CT) is a resource-demanding imaging modality with increasing popularity in the workup of patients with suspected or proven lung cancer. To review the clinical usefulness of this imaging modality in the diagnosis, staging, and pre-operative evaluation, we conducted a systematic literature search, review, and quality assessment using the rapid evidence assessment toolkit and the Oxford Centre for Evidence-Based Medicine methodology. The literature search resulted in 4,208 records including 918 reviews, of which 139 met the predefined criteria and were read in full to identify relevant original articles on F-18 FDG PET-CT (1) in the evaluation of solitary pulmonary nodules (n = 14), (2) in curative-intent treatment trials (n = 9), and (3) in planning of invasive procedures (n = 18). We found the following important results from the literature review: (1) PET-CT can rule out malignancy in most solitary pulmonary nodules due to high sensitivity (recommendation level A). (2) PET-CT reduces the number of futile treatment trials (recommendation level A). (3) The sensitivity of PET-CT in general is insufficient to rule out mediastinal lymph node metastasis (recommendation level A). (1) With few exceptions, solitary pulmonary nodules can safely be considered benign if the PET-CT scan is negative. Exceptions consist of small (<1 cm) and non-solid, solitary pulmonary nodules. These abnormalities should be followed up by CT in a structured programme. (2) No curative-intent treatment should be commenced until a PET-CT scan has excluded occult distant metastases. (3) In general, lymph node metastasis in the mediastinum cannot be ruled out on the basis of a negative PET-CT, and confirmative invasive staging should be performed in most patients before mediastinal metastasis is confirmed or ruled out. (orig.)

  11. Missed rib fractures on evaluation of initial chest CT for trauma patients: pattern analysis and diagnostic value of coronal multiplanar reconstruction images with multidetector row CT.

    Science.gov (United States)

    Cho, S H; Sung, Y M; Kim, M S

    2012-10-01

    The objective of this study was to review the prevalence and radiological features of rib fractures missed on initial chest CT evaluation, and to examine the diagnostic value of additional coronal images in a large series of trauma patients. 130 patients who presented to an emergency room for blunt chest trauma underwent multidetector row CT of the thorax within the first hour during their stay, and had follow-up CT or bone scans as diagnostic gold standards. Images were evaluated on two separate occasions: once with axial images and once with both axial and coronal images. The detection rates of missed rib fractures were compared between readings using a non-parametric method of clustered data. In the cases of missed rib fractures, the shapes, locations and associated fractures were evaluated. 58 rib fractures were missed with axial images only and 52 were missed with both axial and coronal images (p=0.088). The most common shape of missed rib fractures was buckled (56.9%), and the anterior arc (55.2%) was most commonly involved. 21 (36.2%) missed rib fractures had combined fractures on the same ribs, and 38 (65.5%) were accompanied by fracture on neighbouring ribs. Missed rib fractures are not uncommon, and radiologists should be familiar with buckle fractures, which are frequently missed. Additional coronal imagescan be helpful in the diagnosis of rib fractures that are not seen on axial images.

  12. Automated lung module detection at low-dose CT: preliminary experience

    International Nuclear Information System (INIS)

    Goo, Jin-Mo; Lee, Jeong-Won; Lee, Hyun-Ju; Kim, Seung-Wan; Kim, Jong-Hyo; Im, Jung-Gi

    2003-01-01

    To determine the usefulness of a computer-aided diagnosis (CAD) system for the automated detection of lung nodules at low-dose CT. A CAD system developed for detecting lung nodules was used to process the data provided by 50 consecutive low-dose CT scans. The results of an initial report, a second look review by two chest radiologists, and those obtained by the CAD system were compared, and by reviewing all of these, a gold standard was established. By applying the gold standard, a total of 52 nodules were identified (26 with a diameter ≤ 5 mm; 26 with a diameter > 5 mm). Compared to an initial report, four additional nodules were detected by the CAD system. Three of these, identified only at CAD, formed part of the data used to derive the gold standard. For the detection of nodules > 5 mm in diameter, sensitivity was 77% for the initial report, for the second look review, and 88% for the second look review,and 65% for the CAD system. There were 8.0 ± 5.2 false-positive CAD results per CT study. These preliminary results indicate that a CAD system may improve the detection of pulmonary nodules at low-dose CT

  13. Clinical utility of F-18 FDG PET-CT in the initial evaluation of lung cancer.

    Science.gov (United States)

    Madsen, Poul Henning; Holdgaard, Paw Christian; Christensen, Janne Buck; Høilund-Carlsen, Poul Flemming

    2016-10-01

    Positron emission tomography-computed tomography (PET-CT) is a resource-demanding imaging modality with increasing popularity in the workup of patients with suspected or proven lung cancer. To review the clinical usefulness of this imaging modality in the diagnosis, staging, and pre-operative evaluation, we conducted a systematic literature search, review, and quality assessment using the rapid evidence assessment toolkit and the Oxford Centre for Evidence-Based Medicine methodology. The literature search resulted in 4,208 records including 918 reviews, of which 139 met the predefined criteria and were read in full to identify relevant original articles on F-18 FDG PET-CT (1) in the evaluation of solitary pulmonary nodules (n = 14), (2) in curative-intent treatment trials (n = 9), and (3) in planning of invasive procedures (n = 18). We found the following important results from the literature review: 1) PET-CT can rule out malignancy in most solitary pulmonary nodules due to high sensitivity (recommendation level A). 2) PET-CT reduces the number of futile treatment trials (recommendation level A). 3) The sensitivity of PET-CT in general is insufficient to rule out mediastinal lymph node metastasis (recommendation level A). ᅟ 1) With few exceptions, solitary pulmonary nodules can safely be considered benign if the PET-CT scan is negative. Exceptions consist of small (PET-CT scan has excluded occult distant metastases. 3) In general, lymph node metastasis in the mediastinum cannot be ruled out on the basis of a negative PET-CT, and confirmative invasive staging should be performed in most patients before mediastinal metastasis is confirmed or ruled out.

  14. Laparoscopic hand-assisted pancreaticoduodenectomy: initial UK experience.

    Science.gov (United States)

    Ammori, B J

    2004-04-01

    By and large, the limited world experience with laparoscopic pancreaticoduodenectomy (PD) has been unfavorable, but the laparoscopic hand-assisted approach to PD has recently shown promising results. We report the first successful UK experience with laparoscopic hand-assisted PD (LHAPD). A 62-year-old man who presented with painless obstructive jaundice was found at endoscopy, to have an ampullary tumor. Preoperative biopsy specimens confirmed the diagnosis of an adenocarcinoma, and CT showed no evidence of either vascular involvement or metastatic disease. A staging laparoscopy showed no intraabdominal metastases, and an LHAPD was performed using a Gelport. The intraoperative course was uneventful. Two units of blood were transfused intraoperatively, but no postoperative blood transfusion was required. The operative time was 11 h (plus a 30-min break). The patients postoperative recovery was uneventful except for superficial pressure sores over the buttocks and elbows. The patient resumed oral fluid and dietary intake on the 1st and 3rd postoperative days, respectively, and was discharged from hospital on the 9th postoperative day. Histology demonstrated an ampullary adenocarcinoma with clear resection margins and involvement of two of the 13 lymph nodes examined. At 2-month follow-up, the patient remains well and is receiving adjuvant chemotherapy. LHAPD achieves good oncological clearance and can be performed safely in selected patients. The early promising results with this approach will undoubtedly encourage wider adoption of this procedure and are likely to widen the selection criteria.

  15. Experience with contrast-enhanced CT in delayed traumatic intracerebral hematoma

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Shiro; Nakazawa, Shozo; Yokota, Hiroyuki; Isayama, Kazuo; Yajima, Kouzo; Otsuka, Toshibumi [Nippon Medical School, Tokyo

    1984-02-01

    During the four-and-a-half-year period from April, 1976, to September, 1980, out of 257 patients with severe head injuries graded 8 or less by the Glasgow Coma Scale in the Department of Neurosurgery and Critical Care Medicine of the Nippon Medical School, Tokyo, Japan, 33 cases showed the development of delayed traumatic intracerebral hematoma (DTICH) upon the serial computerized tomography (CT). Contrast-enhanced CT was performed in 20 cases of the 33 patients demonstrating DTICH. Among these, 8 cases (40%) indicated the development of DTICH in the lesions of cerebral contusion (a salt-and-pepper appearance in the initial plain CT) which showed a remarkable enhancement, sustaining the extravasation of the contrast medium into the contused brain tissue. The authors discuss the pathogenesis of DTICH and suggest that vasoparalysis in the cerebral contusion might be a factor in the development of DTICH in patients with servere head injuries.

  16. Experience with contrast-enhanced CT in delayed traumatic intracerebral hematoma

    International Nuclear Information System (INIS)

    Kobayashi, Shiro; Nakazawa, Shozo; Yokota, Hiroyuki; Isayama, Kazuo; Yajima, Kouzo; Otsuka, Toshibumi

    1984-01-01

    During the four-and-a-half-year period from April, 1976, to September, 1980, out of 257 patients with severe head injuries graded 8 or less by the Glasgow Coma Scale in the Department of Neurosurgery and Critical Care Medicine of the Nippon Medical School, Tokyo, Japan, 33 cases showed the development of delayed traumatic intracerebral hematoma (DTICH) upon the serial computerized tomography (CT). Contrast-enhanced CT was performed in 20 cases of the 33 patients demonstrating DTICH. Among these, 8 cases (40%) indicated the development of DTICH in the lesions of cerebral contusion (a salt-and-pepper appearance in the initial plain CT) which showed a remarkable enhancement, sustaining the extravasation of the contrast medium into the contused brain tissue. The authors discuss the pathogenesis of DTICH and suggest that vasoparalysis in the cerebral contusion might be a factor in the development of DTICH in patients with servere head injuries. (author)

  17. Percutaneous CT-guided interventional procedures in musculoskeletal system (our experience)

    Energy Technology Data Exchange (ETDEWEB)

    Thanos, Loukas E-mail: loutharad@yahoo.com; Mylona, Sophia; Kalioras, Vasilios; Pomoni, Maria; Batakis, Nikolaos

    2004-06-01

    Percutaneous interventional procedures include a broad spectrum of minimal invasive techniques, which are a useful diagnostic and therapeutic tool. In this study we present our experience in CT-guided percutaneous musculoskeletal biopsies, drainages of musculoskeletal abscesses, facet and sacroiliac joint injection and radiofrequency thermal ablation of painful metastases or osteoid osteomas.

  18. CT-guided thin needles percutaneous cryoablation (PCA) in patients with primary and secondary lung tumors: A preliminary experience

    Energy Technology Data Exchange (ETDEWEB)

    Pusceddu, Claudio, E-mail: clapusceddu@gmail.com [Division of Interventional Radiology, Department of Oncological Radiology, Businco Hospital, Regional Referral Center for Oncologic Diseases, Cagliari, Zip code 09100 (Italy); Sotgia, Barbara, E-mail: barbara.sotgia@gmail.com [Department of Oncological Radiology, Businco Hospital, Regional Referral Center for Oncological Diseases, Cagliari, Zip code 09100 (Italy); Fele, Rosa Maria, E-mail: rosellafele@tiscali.it [Department of Oncological Radiology, Businco Hospital, Regional Referral Center for Oncological Diseases, Cagliari, Zip code 09100 (Italy); Melis, Luca, E-mail: doclucamelis@tiscali.it [Department of Oncological Radiology, Businco Hospital, Regional Referral Center for Oncological Diseases, Cagliari, Zip code 09100 (Italy)

    2013-05-15

    Purpose: To report the data of our initial experience with CT-guided thin cryoprobes for percutaneous cryoablation (PCA) in patients with primary and secondary pulmonary tumors. Material and methods: CT-guided thin needles PCA was performed on 34 lung masses (11 NSCLC = 32%; 23 secondary lung malignancies = 68%) in 32 consecutive patients (24 men and 8 women; mean age 67 ± 10 years) not suitable for surgical resection. Lung masses were treated using two types of cryoprobes: IceRod and IceSeed able to obtain different size of iceball. The number of probes used ranged from 1 to 5 depending on the size of the tumor. After insertion of the cryoprobes into the lesion, the PCA were performed with two 2 (91%) or 3 (9%) cycles each of 12 min of freezing followed by a 4 min active thawing phase and a 4 min passive thawing phase for each one for all treatments. Results: All cryoablation sessions were successfully completed. All primary and metastatic lung tumors were ablated. No procedure-related deaths occurred. Morbidity consisted of 21% (7 of 34) pneumothorax and 3% (1 of 34) cases asymptomatic small pulmonary hemorrhage, respectively, all of CTCAE grade 1 (Common Terminology Criteria for Adverse Events). Low density of entire lesion, central necrosis and solid mass appearance were identify in 21 (62%), 7 (21%) and 6 (17%) of cryoablated tumors, respectively. No lymphadenopathy developed in the region of treated lesions. Technical success (complete lack of enhancement) was achieved in 82%, 97% and 91% of treated lesions at 1-, 3- and 6-months CT follow-up scan, respectively (p < .000). Comparing the tumor longest diameter between the baseline and at 6 month CT images, technical success was revealed in 92% cases (p < .000). Conclusion: Our preliminary experience suggests that PCA is a feasible treatment option. Well-designed clinical trials with a larger patient population are necessary to further investigate the long-term results and prognostic factors.

  19. The utility of first-pass perfusion CT in hyperacute ischemic stroke: early experience

    International Nuclear Information System (INIS)

    Lee, Tae Jin; Lee, Myeong Sub; Kim, Myung Soon; Hong, In Soo; Lee, Young Han; Lee, Ji Yong; Whang, Kum

    2003-01-01

    To evaluate the findings of first-pass perfusion CT in hyperacute stroke patients and to determine the relationship between a perfusion map and final infarct outcome. Thirty-five patients admitted with ischemic stroke within six hours of the onset of symptoms underwent conventional cerebral CT immediately followed by first-pass perfusion CT. Nineteen underwent follow-up CT or MRI, and three types of dynamic perfusion map-cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) - were evaluated by two radiologists. In these 19 patients, initial perfusion maps correlated with final infarct size, determined during follow-up studies. In all 35 patients, major large vessel perfusion abnormalities [middle cerebral artery - MCA MCA and anterior cerebral artery - ACA (n=2); posterior cerebral artery - PCA (n=8)] were detected. On first-pass perfusion maps depicting CBF and MTT, all lesions were detected, and CBF and delayed MTT values were recorded. CBV maps showed variable findings. In all 19 patients who were followed up, the final infarct size of perfusion abnormalities was less than that depicted on CBF and MTT maps, and similar to or much greater than that seen on CBV maps. First-pass perfusion CT scanning is a practical, rapid and advanced imaging technique. In hyperacute stroke patients, it provides important and reliable hemodynamic information as to which brain tissue is salvageable by thrombolytic therapy, and predicts outcome of such treatment

  20. CT enteroclysis in the diagnosis of obscure gastrointestinal bleeding: initial results

    International Nuclear Information System (INIS)

    Jain, T.P.; Gulati, M.S.; Makharia, G.K.; Bandhu, S.; Garg, P.K.

    2007-01-01

    Aim: To evaluate the usefulness of computed tomography (CT) enteroclysis in patients with obscure gastrointestinal (GI) bleeding. Materials and methods: In a prospective study, CT enteroclysis was performed in 21 patients (median age 50 years; range 13-71 years) with obscure GI bleeding in which the source of the bleeding could not be detected despite the patient having undergone both upper GI endoscopic and colonoscopic examinations. The entire abdomen and pelvis was examined in the arterial and venous phases using multisection CT after distending the small intestine with 2 l of 0.5% methylcellulose as a neutral enteral contrast medium and the administration of 150 ml intravenous contrast medium. Results: Adequate distension of the small intestine was achieved in 20 of the 21 (95.2%) patients. Potential causes of GI bleeding were identified in 10 of the 21 (47.6%) patients using CT enteroclysis. The cause of the bleeding could be detected nine of 14 (64.3%) patients with overt, obscure GI bleeding. However, for patients with occult, obscure GI bleeding, the cause of the bleeding was identified in only one of the seven (14.3%) patients. The lesions identified by CT enteroclysis included small bowel tumours (n = 2), small bowel intussusceptions (n = 2), intestinal tuberculosis (n = 2), and vascular lesions (n = 3). All vascular lesions were seen equally well in both the arterial and venous phases. Conclusions: The success rate in detection of the cause of bleeding using CT enteroclysis was 47.6% in patients with obscure GI bleeding. The diagnostic yield was higher in patients with overt, obscure GI bleeding than in those with occult obscure GI bleeding

  1. CT enteroclysis in the diagnosis of obscure gastrointestinal bleeding: initial results

    Energy Technology Data Exchange (ETDEWEB)

    Jain, T.P. [Department ofRadiodiagnosis, All India Institute of Medical Sciences, New Delhi (India); Gulati, M.S. [Department of Imaging, Queen Elizabeth Hospital NHS Trust, London (United Kingdom); Makharia, G.K. [Department of Gastroenterology and Human Nutrition, All India Institute of Medical Sciences, New Delhi (India)]. E-mail: govindmakharia@aiims.ac.in; Bandhu, S. [Department ofRadiodiagnosis, All India Institute of Medical Sciences, New Delhi (India); Garg, P.K. [Department of Gastroenterology and Human Nutrition, All India Institute of Medical Sciences, New Delhi (India)

    2007-07-15

    Aim: To evaluate the usefulness of computed tomography (CT) enteroclysis in patients with obscure gastrointestinal (GI) bleeding. Materials and methods: In a prospective study, CT enteroclysis was performed in 21 patients (median age 50 years; range 13-71 years) with obscure GI bleeding in which the source of the bleeding could not be detected despite the patient having undergone both upper GI endoscopic and colonoscopic examinations. The entire abdomen and pelvis was examined in the arterial and venous phases using multisection CT after distending the small intestine with 2 l of 0.5% methylcellulose as a neutral enteral contrast medium and the administration of 150 ml intravenous contrast medium. Results: Adequate distension of the small intestine was achieved in 20 of the 21 (95.2%) patients. Potential causes of GI bleeding were identified in 10 of the 21 (47.6%) patients using CT enteroclysis. The cause of the bleeding could be detected nine of 14 (64.3%) patients with overt, obscure GI bleeding. However, for patients with occult, obscure GI bleeding, the cause of the bleeding was identified in only one of the seven (14.3%) patients. The lesions identified by CT enteroclysis included small bowel tumours (n = 2), small bowel intussusceptions (n = 2), intestinal tuberculosis (n = 2), and vascular lesions (n = 3). All vascular lesions were seen equally well in both the arterial and venous phases. Conclusions: The success rate in detection of the cause of bleeding using CT enteroclysis was 47.6% in patients with obscure GI bleeding. The diagnostic yield was higher in patients with overt, obscure GI bleeding than in those with occult obscure GI bleeding.

  2. Clinical experience of quantex coordinate software for CT guided stereotactic surgery

    International Nuclear Information System (INIS)

    Yabashi, Toshitake; Ichikawa, Hideo; Yasuda, Eisuke; Tsuruta, Hatsuo; Ishikawa, Yoshihisa; Kimura, Tokuji; Kanamori, Isao

    1991-01-01

    Recently, Quantex Coordinate Software was newly developed for CT-guided stereotactic surgery. We have the opportunity of using this software in 6 cases with intracerebral hematoma for evacuation and 2 cases with brain tumor for needle biopsy by using CT-guided stereotactic surgery. The followings are the features with a little clinical experience. One of the biggest features is that this software can simulate the best expected route of the puncture needle from burr hole to target point before inserting. Also compared with CT 9000 series Software, it has many new functions for more advanced hardware as well as advance standard software. Two cases of intracerebral hematoma for evacuation and 1 case of a brain tumor for a biopsy were carried out using this software mainly as a simulation. In all cases, this software proved to be very useful. (author)

  3. Dynamic crack initiation toughness : experiments and peridynamic modeling.

    Energy Technology Data Exchange (ETDEWEB)

    Foster, John T.

    2009-10-01

    This is a dissertation on research conducted studying the dynamic crack initiation toughness of a 4340 steel. Researchers have been conducting experimental testing of dynamic crack initiation toughness, K{sub Ic}, for many years, using many experimental techniques with vastly different trends in the results when reporting K{sub Ic} as a function of loading rate. The dissertation describes a novel experimental technique for measuring K{sub Ic} in metals using the Kolsky bar. The method borrows from improvements made in recent years in traditional Kolsky bar testing by using pulse shaping techniques to ensure a constant loading rate applied to the sample before crack initiation. Dynamic crack initiation measurements were reported on a 4340 steel at two different loading rates. The steel was shown to exhibit a rate dependence, with the recorded values of K{sub Ic} being much higher at the higher loading rate. Using the knowledge of this rate dependence as a motivation in attempting to model the fracture events, a viscoplastic constitutive model was implemented into a peridynamic computational mechanics code. Peridynamics is a newly developed theory in solid mechanics that replaces the classical partial differential equations of motion with integral-differential equations which do not require the existence of spatial derivatives in the displacement field. This allows for the straightforward modeling of unguided crack initiation and growth. To date, peridynamic implementations have used severely restricted constitutive models. This research represents the first implementation of a complex material model and its validation. After showing results comparing deformations to experimental Taylor anvil impact for the viscoplastic material model, a novel failure criterion is introduced to model the dynamic crack initiation toughness experiments. The failure model is based on an energy criterion and uses the K{sub Ic} values recorded experimentally as an input. The failure model

  4. Implementation of a new CT colonography service: 5 Year experience

    International Nuclear Information System (INIS)

    Lung, P.F.C.; Burling, D.; Kallarackel, L.; Muckian, J.; Ilangovan, R.; Gupta, A.; Marshall, M.; Shorvon, P.; Halligan, S.; Bhatnagar, G.; Bassett, P.; Taylor, S.A.

    2014-01-01

    Aim: To describe our experience using a 5 year audit of computed tomography colonography (CTC) practice and identify factors that influence diagnostic performance to guide implementation in other centres. Material and methods: Consecutive patients referred for CTC at a single institution over a 5 year period were identified, and reporting rates and positive predictive value (PPV) calculated for small polyps, large polyps, and colorectal cancer. Diagnostic performance was compared using the Chi-squared test, and trends over time were examined with logistic regression. The effect of faecal tagging and an intravenous spasmolytic were investigated using Fisher's exact test. Results: In total, 4355 CTC examinations were performed. Overall reporting rates and PPV were 17% and 92%, respectively. Negative predictive value (NPV) for cancer was 99.9%. A significant decrease in reporting rate (p < 0.001) was accompanied by an increase in PPV for small polyps (p = 0.02) following the introduction of faecal tagging. Adequacy rates for CTC improved over time (96% to 99%), with improved adequacy rates when using a spasmolytic, 98% versus 96% without. A significant difference in reporting rates, but not PPV, was found between radiologists. Conclusion: Accurate colonic investigation using CTC can be delivered safely to a high-risk patient population at a single centre. Faecal tagging and an intravenous spasmolytic improve diagnostic performance

  5. Preliminary results from initial in-pile debris bed experiments

    International Nuclear Information System (INIS)

    Rivard, J.B.

    1977-01-01

    An accident in a liquid metal fast breeder reactor (LMFBR) in which molten core material is suddenly quenched with subcooled liquid sodium could result in extensive fragmentation and dispersal of fuel as subcritical beds of frozen particulate debris within the reactor vessel. Since this debris will continue to generate power due to decay of retained fission products, containment of the debris is threatened if the generated heat is not removed. Therefore, the initial safety question is the capacity which debris beds may have for transfer of the decay heat to overlying liquid sodium by natural processes--i.e., without the aid of forced circulation of the coolant. Up to the present time, all experiments on debris bed behavior either have used substitute materials (e.g., sand and water) or have employed actual materials, but atypical heating methods. Increased confidence in the applicability of debris bed simulations is afforded if the heat is generated within the fuel component of the appropriate fast reactor materials. The initial series of in-pile tests reported on herein constitutes the first experiments in which the internal heating mode has been produced in particulate oxide fuel immersed in liquid sodium. Fission heating of the fully-enriched UO 2 in the experiment while it is contained within Sandia Laboratories Annular Core Pulse Reactor (ACPR), operating in its steady-state mode, approximates the decay heating of debris. Preliminary results are discussed

  6. Stanford type A aortic dissection with closed false lumen: Analysis of prognostic factors at initial CT or MRI

    Energy Technology Data Exchange (ETDEWEB)

    Matsuoka, Yohjiro; Sakamoto, Ichiro; Ogawa, Yohji; Sueyoshi, Eijun; Hayashi, Kuniaki; Takagi, Masatake [Nagasaki Univ. (Japan). School of Medicine; Narimatsu, Motoharu

    1997-08-01

    Nineteen patients with Stanford type A acute aortic dissection with closed false lumen were reviewed. In the follow-up examinations, ulcerlike projection (ULP) in the ascending aorta (AA) or aortic arch (AR) was identified in 8 of 19 patients. In 5 of these 8 patients, acute cardiac tamponade occurred and 3 of them died. In the other 11 patients, there was no mortality, and only one patient underwent elective surgery. The appearance of ULP in the AA/AR is considered an indication for urgent surgery because it is regarded as a precursor of lethal complications such as cardiac tamponade. The purpose of this study was to investigate predictors of the appearance of ULP in the AA/AR with early imagings (CT or MRI) before the appearance of ULP. The patients were divided into two groups: patients with ULP in the AA/AR (8 patients) and others (11 patients). Initial CT or MRI findings of the thoracic aorta were retrospectively statistically analyzed in each group. Three predictive factors were statistically significant for the appearance of ULP in the AA/AR (diameter of the AA{>=}5 cm, thickness of the false lumen of the AA{>=}1 cm, thickness of the false lumen of the AA{>=} that of the descending aorta). Close attention should be paid, if any of these 3 factors is observed at initial CT or MRI. (author)

  7. Stanford type A aortic dissection with closed false lumen: Analysis of prognostic factors at initial CT or MRI

    International Nuclear Information System (INIS)

    Matsuoka, Yohjiro; Sakamoto, Ichiro; Ogawa, Yohji; Sueyoshi, Eijun; Hayashi, Kuniaki; Takagi, Masatake; Narimatsu, Motoharu.

    1997-01-01

    Nineteen patients with Stanford type A acute aortic dissection with closed false lumen were reviewed. In the follow-up examinations, ulcerlike projection (ULP) in the ascending aorta (AA) or aortic arch (AR) was identified in 8 of 19 patients. In 5 of these 8 patients, acute cardiac tamponade occurred and 3 of them died. In the other 11 patients, there was no mortality, and only one patient underwent elective surgery. The appearance of ULP in the AA/AR is considered an indication for urgent surgery because it is regarded as a precursor of lethal complications such as cardiac tamponade. The purpose of this study was to investigate predictors of the appearance of ULP in the AA/AR with early imagings (CT or MRI) before the appearance of ULP. The patients were divided into two groups: patients with ULP in the AA/AR (8 patients) and others (11 patients). Initial CT or MRI findings of the thoracic aorta were retrospectively statistically analyzed in each group. Three predictive factors were statistically significant for the appearance of ULP in the AA/AR (diameter of the AA≥5 cm, thickness of the false lumen of the AA≥1 cm, thickness of the false lumen of the AA≥ that of the descending aorta). Close attention should be paid, if any of these 3 factors is observed at initial CT or MRI. (author)

  8. Initial experience of tritium exposure control at JET

    International Nuclear Information System (INIS)

    Patel, B.; Campling, D.C.; Schofield, P.A.; Macheta, P.; Sandland, K.

    1998-01-01

    Some of the safety procedures and controls in place for work with tritium are described, and initial operational experience of handling tritium is discussed. A description is given of work to rectify a water leak in a JET neutral beam heating component, which involved man-access to a confined volume to perform repairs, at tritium levels about 100 DAC (80 MBq/m 3 . HTO). Control measures involving use of purge and extract ventilation, and of personal protection using air-fed pressurized suits are described. Results are given of the internal doses to project staff and of atmospheric discharges of tritium during the repair outage. (P.A.)

  9. Experimental test accelerator: description and results of initial experiments

    International Nuclear Information System (INIS)

    Fessenden, T.; Birx, D.; Briggs, R.

    1980-01-01

    The ETA is a high current (10,000 Amp) linear induction accelerator that produces short (30 ns) pulses of electrons at 5 MeV twice per second or in bursts of 5 pulses separated by as little as one millisecond. At this time the machine has operated at 65% of its design current and 90% of the design voltage. This report contains a description of the accelerator and its diagnostics; the results of the initial year of operation; a comparison of design codes with experiments on beam transport; and a discussion of some of the special problems and their status

  10. Initial acceptance test experience with FFTF plant equipment

    International Nuclear Information System (INIS)

    Brown, R.K.; Coleman, K.A.; Mahaffey, M.K.; McCargar, C.G.; Young, M.W.

    1978-09-01

    The purpose of this paper is to examine the initial acceptance test experience of certain pieces of auxiliary equipment of the Fast Flux Test Facility (FFTF). The scope focuses on the DHX blowers and drive train, inert gas blowers, H and V containment isolation valves, and the Surveillance and In-service Inspection (SISI) transporter and trolley. For each type of equipment, the discussion includes a summary of the design and system function, installation history, preoperational acceptance testing procedures and results, and unusual events and resolutions

  11. Initial investigation of a novel light-scattering gel phantom for evaluation of optical CT scanners for radiotherapy gel dosimetry

    International Nuclear Information System (INIS)

    Bosi, Stephen; Naseri, Pourandokht; Puran, Alicia; Davies, Justin; Baldock, Clive

    2007-01-01

    There is a need for stable gel materials for phantoms used to validate optical computerized tomography (CT) scanners used in conjunction with radiation-induced polymerizing gel dosimeters. Phantoms based on addition of light-absorbing dyes to gelatine to simulate gel dosimeters have been employed. However, to more accurately simulate polymerizing gels one requires phantoms that employ light-scattering colloidal suspensions added to the gel. In this paper, we present the initial results of using an optical CT scanner to evaluate a novel phantom in which radiation-exposed polymer gels are simulated by the addition of colloidal suspensions of varying turbidity. The phantom may be useful as a calibration transfer standard for polymer gel dosimeters. The tests reveal some phenomena peculiar to light-scattering gels that need to be taken into account when calibrating polymer gel dosimeters

  12. Initial CT manifestations of invasive pulmonary aspergillosis in 45 non-HIV immunocompromised patients: association with patient outcome?

    International Nuclear Information System (INIS)

    Horger, Marius; Hebart, Holger; Einsele, Hermann; Lengerke, Claudia; Claussen, C.D.; Vonthein, Reinhard; Pfannenberg, Christina

    2005-01-01

    /46) of IPA episodes. Conclusion: Initial CT findings of invasive pulmonary aspergillosis consist mainly of small nodules or patchy consolidations, showing in 82% of cases an early halo sign. Serious pulmonary hemorrhage was an infrequent clinical complication in our series, with an attributable mortality of 4.3%. IPA-related lethality was 26%, in our cohort. None of the early HRCT signs seemed to predict outcome

  13. Initial experience with the NRC significance determination process

    Energy Technology Data Exchange (ETDEWEB)

    Madison, A.L. [Office of Nuclear Reactor Regulation, US Nuclear Regulatory Commission (United States)

    2001-07-01

    The U.S. Nuclear Regulatory Commission (NRC) has revamped its inspection, assessment, and enforcement programs for commercial nuclear power plants. The new oversight process uses more objective, timely, and safety-significant criteria in assessing performance, while seeking to more effectively and efficiently regulate the industry. The NRC tested the new process at thirteen reactors at nine sites across the country on a pilot basis in 1999 to identify what things worked well and what improvements were called for before beginning Initial Implementation at all US nuclear power plants on April 2, 2000. After a year of experience has been gained with the new oversight process at all US plants, the NRC anticipates making further improvements based on this wider experience. (author)

  14. Initial experience with the NRC significance determination process

    International Nuclear Information System (INIS)

    Madison, A.L.

    2001-01-01

    The U.S. Nuclear Regulatory Commission (NRC) has revamped its inspection, assessment, and enforcement programs for commercial nuclear power plants. The new oversight process uses more objective, timely, and safety-significant criteria in assessing performance, while seeking to more effectively and efficiently regulate the industry. The NRC tested the new process at thirteen reactors at nine sites across the country on a pilot basis in 1999 to identify what things worked well and what improvements were called for before beginning Initial Implementation at all US nuclear power plants on April 2, 2000. After a year of experience has been gained with the new oversight process at all US plants, the NRC anticipates making further improvements based on this wider experience. (author)

  15. CT-TRX1, a triggered-reconnection compact toroid experiment

    International Nuclear Information System (INIS)

    Hoffman, A.L.

    1980-05-01

    A new compact toroid experiment, CT-TRX1, based on the field reversed theta pinch is under construction. The unique feature of this experiment is the incorporation of several quasi-steady and pulsed magnets to carefully control the reconnection process. The motivation for this emphasis is to duplicate and extend the results reported by Kurtmullaev, et al., where delayed reconnection produced efficient axial shock heating and resulted in large diameter compact toroids which exhibited complete MHD stability for the 100 μsec decay time of their pulsed magnets. CT-TRX1 incorporates moderate E/sub theta/ radial shock heating, along with the triggered reconnection capability, to investigate the full range of conditions between the USSR experiments and the radial shock heated experiments at LASL, where m = 2 rotational instabilities occur. An additional feature of CT-TRX1 is the incorporation of a compound magnet which will provide long magnetic field decay times. The requirements for both high field quasi-steady outer magnets, and several high voltage, individually triggered pulsed inner magnets, present unique engineering design problems which are discussed

  16. Initial experience in hybrid PET-MRI for evaluation of refractory focal onset epilepsy.

    Science.gov (United States)

    Shin, Hae W; Jewells, Valerie; Sheikh, Arif; Zhang, Jingwen; Zhu, Hongtu; An, Hongyu; Gao, Wei; Shen, Dinggang; Hadar, Eldad; Lin, Weili

    2015-09-01

    We aim to evaluate the utility/improved accuracy of hybrid PET/MR compared to current practice separate 3T MRI and PET-CT imaging for localization of seizure foci. In a pilot study, twenty-nine patients undergoing epilepsy surgery evaluation were imaged using PET/MR. This subject group had 29 previous clinical 3T MRI as well as 12 PET-CT studies. Prior clinical PET and MR images were read sequentially while the hybrid PET/MR was concurrently read. The median interval between hybrid PET/MR and prior imaging studies was 5 months (range 1-77 months). In 24 patients, there was no change in the read between the clinical exams and hybrid PET/MR while new anatomical or functional lesions were identified by hybrid PET/MR in 5 patients without significant clinical change. Four new anatomical MR lesions were seen with concordant PET findings. The remaining patient revealed a new abnormal PET lesion without an MR abnormality. All new PET/MR lesions were clinically significant with concordant EEG and/or SPECT results as potential epileptic foci. Our initial hybrid PET-MRI experience increased diagnostic yields for detection of potential epileptic lesions. This may be due to the unique advantage of improved co-registration and simultaneous review of both structural and functional data. Copyright © 2015 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  17. Initiation process of a thrust fault revealed by analog experiments

    Science.gov (United States)

    Yamada, Yasuhiro; Dotare, Tatsuya; Adam, Juergen; Hori, Takane; Sakaguchi, Hide

    2016-04-01

    We conducted 2D (cross-sectional) analog experiments with dry sand using a high resolution digital image correlation (DIC) technique to reveal initiation process of a thrust fault in detail, and identified a number of "weak shear bands" and minor uplift prior to the thrust initiation. The observations suggest that the process can be divided into three stages. Stage 1: characterized by a series of abrupt and short-lived weak shear bands at the location where the thrust will be generated later. Before initiation of the fault, the area to be the hanging wall starts to uplift. Stage 2: defined by the generation of the new thrust and its active displacement. The location of the new thrust seems to be constrained by its associated back-thrust, produced at the foot of the surface slope (by the previous thrust). The activity of the previous thrust turns to zero once the new thrust is generated, but the timing of these two events is not the same. Stage 3: characterized by a constant displacement along the (new) thrust. Similar minor shear bands can be seen in the toe area of the Nankai accretionary prism, SW Japan and we can correlate the along-strike variations in seismic profiles to the model results that show the characteristic features in each thrust development stage.

  18. Puzzling initial conditions in the R{sub h} = ct model

    Energy Technology Data Exchange (ETDEWEB)

    Bengochea, Gabriel R. [CONICET-Universidad de Buenos Aires, Instituto de Astronomia y Fisica del Espacio (IAFE), Buenos Aires (Argentina); Leon, Gabriel [Universidad de Buenos Aires, Ciudad Universitaria, PabI, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Buenos Aires (Argentina)

    2016-11-15

    In recent years, some studies have drawn attention to the lack of large-angle correlations in the observed cosmic microwave background (CMB) temperature anisotropies with respect to that predicted within the standard ΛCDM model. Lately, it has been argued that such a lack of correlations could be explained in the framework of the so-called R{sub h} = ct model without inflation. The aim of this work is to study whether there is a mechanism to generate, through a quantum field theory, the primordial power spectrum presented by these authors. Specifically, we consider two different scenarios: first, we assume a scalar field dominating the early Universe in the R{sub h} = ct cosmological model, and second, we deal with the possibility of adding an early inflationary phase to the mentioned model. During the analysis of the consistency between the predicted and observed amplitudes of the CMB temperature anisotropies in both scenarios, we run into deep issues which indicate that it is not clear how to characterize the primordial quantum perturbations within the R{sub h} = ct model. (orig.)

  19. 18F-FDG PET/CT for initial staging in breast cancer patients. Is there a relevant impact on treatment planning compared to conventional staging modalities?

    International Nuclear Information System (INIS)

    Krammer, J.; Schnitzer, A.; Kaiser, C.G.; Buesing, K.A.; Schoenberg, S.O.; Wasser, K.; Sperk, E.; Brade, J.; Wasgindt, S.; Suetterlin, M.; Sutton, E.J.

    2015-01-01

    To evaluate the impact of whole-body 18 F-FDG PET/CT on initial staging of breast cancer in comparison to conventional staging modalities. This study included 102 breast cancer patients, 101 patients were eligible for evaluation. Preoperative whole-body staging with PET/CT was performed in patients with clinical stage ≥ T2 tumours or positive local lymph nodes (n = 91). Postoperative PET/CT was performed in patients without these criteria but positive sentinel lymph node biopsy (n = 10). All patients underwent PET/CT and a conventional staging algorithm, which included bone scan, chest X-ray and abdominal ultrasound. PET/CT findings were compared to conventional staging and the impact on therapeutic management was evaluated. PET/CT led to an upgrade of the N or M stage in overall 19 patients (19 %) and newly identified manifestation of breast cancer in two patients (2 %). PET/CT findings caused a change in treatment of 11 patients (11 %). This is within the range of recent studies, all applying conventional inclusion criteria based on the initial T and N status. PET/CT has a relevant impact on initial staging and treatment of breast cancer when compared to conventional modalities. Further studies should assess inclusion criteria beyond the conventional T and N status, e.g. tumour grading and receptor status. (orig.)

  20. Determination of urinary stone composition using dual-energy spectral CT: Initial in vitro analysis

    International Nuclear Information System (INIS)

    Li, X.-H.; Zhao, R.; Liu, B.; Yu, Y.-Q.

    2013-01-01

    Aim: To evaluate the feasibility of determining the chemical composition of urinary stones using computed tomography (CT) spectral imaging (SI) Materials and methods: Two hundred and ten urinary stones were scanned in vitro using the SI mode and conventional polychromatic imaging (CPI; 120 kVp) mode. The radiodensity at 50 keV and 120 kVp, the mean calcium density (CD), and the water density (WD) were measured using the 50 keV images, 120 kVp images, calcium-based images, and water-based images, respectively. These parameters and the calcium–water ratio (CWR) were compared between different types of stones. CWR was defined as: CWR = ‌calcium density/water density‌. Results: According to the results determined by infrared spectroscopy, 116 pure urinary stones were divided into five groups: uric acid (UA, n = 16), struvite (STR, n = 23), cystine (CYS, n = 10), calcium phosphate (CaP, n = 29), and calcium oxalate (COX, n = 38). CD, CWR, and the radiodensity of stones at 50 keV CT imaging of each group were as follows: UA (−3.55 ± 10.85 mg/ml, 0.03 ± 0.05, 510.08 ± 157.29 HU); STR (224.99 ± 64.28 mg/ml, 0.19 ± 0.07, 1058.58 ± 260.13 HU); CYS (139.67 ± 34.66 mg/ml, 0.13 ± 0.03, 725.75 ± 142.35 HU); CaP (619.39 ± 26.13 mg/ml, 0.69 ± 0.11, 2617.46 ± 186.22 HU); COX (518.61 ± 95.5 mg/ml, 0.58 ± 0.1, 2247.47 ± 379.51 HU). The differences in the CD, CRW, and radiodensity of stones at 50 keV CT imaging among the groups were statistically significant by binary comparison (p < 0.05). There were no significant differences in the radiodensity of stones at 120 keV CT imaging between UA and CYS (p = 0.267), CaP and COX (p = 0.065), and in the WD between STR and CYS (p = 0.108). Conclusion: SI provides a novel method to better characterize pure urinary stones using the mean CD, CWR, and the radiodensity of stones at 50 keV CT imaging

  1. CT-guided percutaneous cryoablation of osteoid osteoma in children: an initial study

    International Nuclear Information System (INIS)

    Wu, Bin; Xiao, Yue-Yong; Zhang, Xiao; Zhao, Lei; Carrino, John A.

    2011-01-01

    The purpose of this study was to evaluate the safety and efficacy of CT-guided percutaneous cryoablation for osteoid osteoma in children. This study was approved by the institutional ethics committee. From January 2007 to July 2008, six children (four boys, two girls, mean age 12.6 years old) with osteoid osteoma were treated with CT-guided percutaneous cryoablation. The procedures were carried out under conscious sedation and local anesthesia. CT guidance was used for procedural planning, instrument guidance, and monitoring. An argon-based cryoablation system was used. Each cryoablation included two freezing-thawing cycles. Follow-up was performed to assess technical and clinical outcome for a minimum of 12 months. A visual analog scale (VAS) was used to assess severity of pain pre- and post-procedure, and mean VAS for the group was compared pre- and post-procedure with a t-test. The mean clinical follow-up period was 28.7 months (ranging from 18 to 36 months). Cryoablation was technically and clinically successful for all patients. No major immediate or delayed complications were observed. Significant pain relief (P <0.05) was observed in all patients after operation. Mean VAS were 6.57 ± 0.55 pre-procedure and 0.57 ± 0.10 1 month post-procedure. Patients were allowed to fully bear their weight and function without limitation within 3 days after the procedure. Pain recurrence was not observed in any patient. Percutaneous cryoablation is safe and effective for the treatment of osteoid osteomas in children. Notably, this procedure can be accomplished without general anesthesia. (orig.)

  2. LWR aerosol containment experiments (LACE) program and initial test results

    International Nuclear Information System (INIS)

    Muhlestein, L.D.; Hilliard, R.K.; Bloom, G.R.; McCormack, J.D.; Rahn, F.J.

    1985-01-01

    The LWR aerosol containment experiments (LACE) program is described. The LACE program is being performed at the Hanford Engineer Development Laboratory (operated by Westinghouse Hanford Company) and the initial tests are sponsored by EPRI. The objectives of the LACE program are: to demonstrate, at large-scale, inherent radioactive aerosol retention behavior for postulated high consequence LWR accident situations; and to provide a data base to be used for aerosol behavior . Test results from the first phase of the LACE program are presented and discussed. Three large-scale scoping tests, simulating a containment bypass accident sequence, demonstrated the extent of agglomeration and deposition of aerosols occurring in the pipe pathway and vented auxiliary building under realistic accident conditions. Parameters varied during the scoping tests were aerosol type and steam condensation

  3. Initial clinical experience with a sac-anchoring endoprosthesis for aortic aneurysm repair.

    Science.gov (United States)

    Donayre, Carlos E; Zarins, Christopher K; Krievins, Dainis K; Holden, Andrew; Hill, Andrew; Calderas, Carlos; Velez, Jaime; White, Rodney A

    2011-03-01

    All current aortic endografts depend on proximal and distal fixation to prevent migration. However, migration and rupture can occur, particularly in patients with aortic necks that are short or angulated, or both. We present our initial clinical experience with a new sac-anchoring endoprosthesis designed to anchor and seal the device within the aneurysm sac. The initial worldwide experience using a new endoprosthesis for the treatment of aortic aneurysms (Nellix Endovascular, Palo Alto, Calif) was reviewed. The endoprosthesis consists of dual balloon-expandable endoframes surrounded by polymer-filled endobags designed to obliterate the aneurysm sac and maintain endograft position. Clinical results and follow-up contrast computed tomography (CT) scans at 30 days and 6 and 12 months were reviewed. The endograft was successfully deployed in 21 patients with infrarenal aortic aneurysms measuring 5.7 ± 0.7 cm (range, 4.3-7.4 cm). Two patients with common iliac aneurysms were treated with sac-anchoring extenders that maintained patency of the internal iliac artery. Infusion of 71 ± 37 mL of polymer (range, 19-158 mL) into the aortic endobags resulted in complete aneurysm exclusion in all patients. Mean implant time was 76 ± 35 minutes, with 33 ± 17 minutes of fluoroscopy time and 180 ± 81 mL of contrast; estimated blood loss was 174 ± 116 mL. One patient died during the postoperative period (30-day mortality, 4.8%), and one died at 10 months from non-device-related causes. During a mean follow-up of 8.7 ± 3.1 months and a median of 6.3 months, there were no late aneurysm- or device-related adverse events and no secondary procedures. CT imaging studies at 6 months and 1 year revealed no increase in aneurysm size, no device migration, and no new endoleaks. One patient had a limited proximal type I endoleak at 30 days that resolved at 60 days and remained sealed. One patient has an ongoing distal type I endoleak near the iliac bifurcation, with no change in aneurysm

  4. Discharge initiation experiments in the Tokapole II tokamak

    International Nuclear Information System (INIS)

    Shepard, D.A.

    1984-01-01

    Experiments in the Tokapole II tokamak demonstrate the benefits of high density (n/sub e//n/sub o/ greater than or equal to 0.01) preionization by reducing four quantities at startup: necessary toroidal loop voltage (V 1 ) (50%), volt-second consumption (40-50%), impurity radiation (25-50%), and runaway electron production (approx. 80-100%). A zero-dimensional code models the loop voltage reduction dependence on preionization density and predicts a similar result for reactor scale devices. The code shows low initial resistivity and a high resistivity time derivative contribute to loop voltage reduction. Microwaves at the electron cyclotron resonance (ECR) frequency and plasma gun injection produce high density preionization, which reduces the initial V 1 , volt-second consumption, and runaways. The ECR preionization also reduces impurity radiation by shortening the time from voltage application to current channel formation. This, evidently, reduces the total plasma-wall interaction at startup. The power balance of the ECR plasma in a toroidal-field-only case was studied using Langmuir probes and impurity doping. The vertical electric field and current, which result from curvature drift, were measured as approx. 10 V/cm and 50 amps, respectively, and exceeded expected values for the bulk electron temperature (approx. 10 eV)

  5. Initially curved microplates under electrostatic actuation: theory and experiment

    KAUST Repository

    Saghir, Shahid

    2016-07-01

    Microplates are the building blocks of many micro-electro-mechanical systems. It is common for them to experience initial curvature imperfection due to residual stresses caused by the micro fabrication process. Such plates are essentially different from perfectly flat ones and cannot be modeled using flat plate models. In this paper, we adopt a dynamic analog of the von Karman governing equations of imperfect plates. These equations are then used to develop a reduced order model based on the Galerkin procedure, to simulate the static and dynamic behavior of the microplate under electrostatic actuation. To validate the simulation results, an initially curved imperfect microplate made of silicon nitride is fabricated and tested. The static behaviour of the microplate is investigated when applying a DC voltage Vdc. Then, the dynamic behaviour of the microplate is examined under the application of a harmonic AC voltage, Vac, superimposed to Vdc. The simulation results show good agreement with the experimentally measured responses. © 2016 IOP Publishing Ltd.

  6. [Characterization of photochemical smog chamber and initial experiments].

    Science.gov (United States)

    Jia, Long; Xu, Yong-Fu; Shi, Yu-Zhen

    2011-02-01

    A self-made new indoor environmental chamber facility for the study of atmospheric processes leading to the formation of ozone and secondary organic aerosols has been introduced and characterized. The characterization experiments include the measurements of wall effects for reactive species and the determination of chamber dependent * OH radical sources by CO-NO(x) irradiation experiments. Preliminary ethene-NO(x) and benzene-NO(x) experiments were conducted as well. The results of characterization experiments show that the wall effects for O3 and NO2 in a new reactor are not obvious. Relative humidity has a great effect on the wall losses in the old reactor, especially for O3. In the old reactor, the rate constant for O3 wall losses is obtained to be 1.0 x 10(-5) s(-1) (RH = 5%) and 4.0 x10(-5) s(-1) (RH = 91%), whereas for NO2, it is 1.0 x 10(-6) s(-1) (RH = 5%) and 0.6 x 10(-6) s(-1) (RH = 75%). The value for k(NO2 --> HONO) determined by CO-NO(x) irradiation experiments is (4.2-5.2) x 10(-5) s(-1) and (2.3-2.5) x 10(-5) s(-1) at RH = 5% and RH 75% -77%, respectively. The average *OH concentration is estimated to be (2.1 +/- 0.4) x 10(6) molecules/cm3 by using a reaction rate coefficient of CO and * OH. The sensitivity of chamber dependent auxiliary reactions to the O3 formation is discussed. Results show that NO2 --> HONO has the greatest impact on the O3 formation during the initial stage, N2O5 + H2O --> 2HNO3 has a minus effect to maximum O3 concentration, and that the wall losses of both O3 and NO2 have little impact on the O3 formation. The results from the ethene-NO(x) and benzene-NO(x) experiments are in good agreement with those from the MCM simulation, which reflects that the facility for the study of the formation of secondary pollution of ozone and secondary organic aerosols is reliable. This demonstrates that our facility can be further used in the deep-going study of chemical processes in the atmosphere.

  7. Shock initiation experiments on ratchet grown PBX 9502

    Energy Technology Data Exchange (ETDEWEB)

    Gustavsen, Richard L [Los Alamos National Laboratory; Thompson, Darla G [Los Alamos National Laboratory; Olinger, Barton W [Los Alamos National Laboratory; Deluca, Racci [Los Alamos National Laboratory; Bartram, Brian D [Los Alamos National Laboratory; Pierce, Timothy H [Los Alamos National Laboratory; Sanchez, Nathaniel J [Los Alamos National Laboratory

    2010-01-01

    This study compares the shock initiation behavior of PBX 9502 pressed to less than nominal density (nominal density is 1.890 {+-} 0.005 g/cm{sup 3}) with PBX 9502 pressed to nominal density and then ''ratchet grown'' to low density. PBX 9502 is an insensitive plastic bonded explosive consisting of 95 weight % dry-aminated tri-amino-tri-nitro-benzene (TATB) and 5 weight % Kel-F 800 plastic binder. ''Ratchet growth'' - an irreversible increase in specific volume - occurs when an explosive based on TATB is temperature cycled. The design of our study is as follows: PBX 9502, all from the same lot, received the following four treatments. Samples in the first group were pressed to less than nominal density. These were not ratchet grown and used as a baseline. Samples in the second group were pressed to nominal density and then ratchet grown by temperature cycling 30 times between -54 C and +80 C. Samples in the final group were pressed to nominal density and cut into 100 mm by 25.4 mm diameter cylinders. During thermal cycling the cylinders were axially constrained by a 100 psi load. Samples for shock initiation experiments were cut perpendicular (disks) and parallel (slabs) to the axial load. The four sample groups can be summarized with the terms pressed low, ratchet grown/no load, axial load/disks, and axial load/slabs. All samples were shock initiated with nearly identical inputs in plate impact experiments carried out on a gas gun. Wave profiles were measured after propagation through 3, 4, 5, and 6 mm of explosive. Side by side comparison of wave profiles from different samples is used as a measure of relative sensitivity. All reduced density samples were more shock sensitive than nominal density PBX 9502. Differences in shock sensitivity between ratchet grown and pressed to low density PBX 9502 were small, but the low density pressings are slightly more sensitive than the ratchet grown samples.

  8. Determination of entry site for acute type A aortic dissection by initial enhanced CT-scan

    International Nuclear Information System (INIS)

    Mase, Takenori; Narumiya, Chihiro; Aoyama, Takahiko; Nagata, Yoshihisa

    2002-01-01

    Acute type A aortic dissection presents a surgical emergency because conservative therapy is not effective in the majority of instances. Enhanced CT-scan of the chest is commonly available and is considered to be an optimal diagnostic method for this disease. The operative strategy is to resect the primary tear to close the entry site of the aortic dissection and replace it with a tubular Dacron graft. Therefore, the existence of the entry site is important in determining the operative procedure. Based on the numerical value of the enhanced CT-scan inspection, the present study seeks to preoperatively identify the location of the presumed entry site in aortic dissection. From May 1996 to June 1999, 21 consecutive patients (Marfan's syndrome excluded) with acute type A aortic dissection underwent surgical treatment. Nineteen patients were preoperatively examined by enhanced CT-scan: 11 men and 8 women, with a mean age of 61 years. CT-scan slices used for early diagnosis were of the ascending aorta, aortic arch, descending aorta, and thoracoabdominal aorta. The largest diameters of the whole and true lumen were measured from cross-sectional aortic images with a personal computer, and the areas of the whole and true lumen were obtained by the manual tracing method. The true ratio was calculated for the largest diameter and area of the whole lumen. The nineteen patients were divided into two groups according to the location of the entry site based on the operating views. Seven patients with the entry site in the ascending aorta were classified as group A, and twelve patients with the entry site further in the aortic arch and descending aorta were classified as group B. Comparisons were performed by non-parametric analysis. Moreover, a discriminant analysis was applied to evaluate the classification between the two groups. The ratio of the largest diameter of the true lumen in group A at the level of the ascending and descending aorta was significantly greater than that

  9. Determination of entry site for acute type A aortic dissection by initial enhanced CT-scan

    Energy Technology Data Exchange (ETDEWEB)

    Mase, Takenori; Narumiya, Chihiro; Aoyama, Takahiko; Nagata, Yoshihisa [Aichi Medical Univ., Nagakute (Japan). School of Medicine

    2002-01-01

    Acute type A aortic dissection presents a surgical emergency because conservative therapy is not effective in the majority of instances. Enhanced CT-scan of the chest is commonly available and is considered to be an optimal diagnostic method for this disease. The operative strategy is to resect the primary tear to close the entry site of the aortic dissection and replace it with a tubular Dacron graft. Therefore, the existence of the entry site is important in determining the operative procedure. Based on the numerical value of the enhanced CT-scan inspection, the present study seeks to preoperatively identify the location of the presumed entry site in aortic dissection. From May 1996 to June 1999, 21 consecutive patients (Marfan's syndrome excluded) with acute type A aortic dissection underwent surgical treatment. Nineteen patients were preoperatively examined by enhanced CT-scan: 11 men and 8 women, with a mean age of 61 years. CT-scan slices used for early diagnosis were of the ascending aorta, aortic arch, descending aorta, and thoracoabdominal aorta. The largest diameters of the whole and true lumen were measured from cross-sectional aortic images with a personal computer, and the areas of the whole and true lumen were obtained by the manual tracing method. The true ratio was calculated for the largest diameter and area of the whole lumen. The nineteen patients were divided into two groups according to the location of the entry site based on the operating views. Seven patients with the entry site in the ascending aorta were classified as group A, and twelve patients with the entry site further in the aortic arch and descending aorta were classified as group B. Comparisons were performed by non-parametric analysis. Moreover, a discriminant analysis was applied to evaluate the classification between the two groups. The ratio of the largest diameter of the true lumen in group A at the level of the ascending and descending aorta was significantly greater than

  10. Discharge initiation experiments in the Tokapole II tokamak

    International Nuclear Information System (INIS)

    Shepard, D.A.

    1984-06-01

    Experiments in the Tokapole II tokamak demonstrate the benefits of high density (n/sub e//n 0 greater than or equal to 0.01) preionization by reducing four quantities at startup: necessary toroidal loop voltage (V 1 ) (50%), volt-second consumption (40 to 50%), impurity radiation (25 to 50%), and runaway electron production (approx. 80 to 100%). A zero-dimensional code models the loop voltage reduction dependence on preionization density and predicts a similar result for reactor scale devices. The code shows low initial resistivity and a high resistivity time derivative contribute to loop voltage reduction. The power balance of the ECR plasma in a toroidal-field-only case was studied. Langmuir probes and impurity doping were used. The vertical electric field (E/sub v/) and current (I/sub v/), which result from curvature drift, were measured (E/sub v/ approx. 10 V/cm and I/sub v/ approx. 50 Amps) and exceeded expected values for the bulk electron temperature (approx. 10 eV). A series of experiments with external windings to simulate field errors perpendicular to the toroidal field was done. The results imply that an error field of 0.1% of the toroidal field is deleterious to ECR plasma density

  11. Medical student perceptions of an initial collaborative immersion experience.

    Science.gov (United States)

    House, Joseph B; Cedarbaum, Jacob; Haque, Fatema; Wheaton, Michael; Vredeveld, Jennifer; Purkiss, Joel; Moore, Laurel; Santen, Sally A; Daniel, Michelle

    2018-03-01

    Recent reviews of interprofessional education (IPE) highlight the need for innovative curricula focused on longitudinal clinical learning. We describe the development and early outcomes of the initial clinical experience (ICE), a longitudinal practice-based course for first-year medical students. While IPE courses focus on student-to-student interaction, ICE focuses on introducing students to interprofessional collaboration. Students attend 14 sessions at one of 18 different clinical sites. They work directly with different health professionals from among 17 possible professions, including nurses, pharmacists, social workers, and respiratory, occupational, and physical therapists. Between 2015 and 2016, 167 students completed the course, and 81 completed the end-of-course evaluation. Students agreed or strongly agreed that ICE meaningfully contributed to their understanding of healthcare teams and different professional roles (86%), improved their understanding of healthcare systems (84%), improved their ability to communicate with healthcare professionals (61%), and improved their ability to work on interprofessional teams (65%). Select themes from narrative comments suggest that clinical immersion improves understanding of professional roles, helps students understand their own future roles in healthcare teams, and increases awareness of and respect for other professionals, with the potential to change future practice. ICE may be a template for other schools wishing to expand their current educational offerings, by engaging learners in more authentic, longitudinal clinical experiences with practicing healthcare professionals.

  12. [Initiation, promotion, initiation experiments with radon and cigarette smoke: Lung tumors in rats]. Progress report

    International Nuclear Information System (INIS)

    Moolgavkar, S.H.

    1994-01-01

    During the past several years, the authors have made considerable progress in modeling carcinogenesis in general, and in modeling radiation carcinogenesis, in particular. They present an overview of their progress in developing stochastic carcinogenesis models and applying them to experimental and epidemiologic data sets. Traditionally, cancer models have been used for the analysis of incidence (or prevalence) data in epidemiology and time to tumor data in experimental studies. The relevant quantities for the analysis of these data are the hazard function and the probability of tumor. The derivation of these quantities is briefly described here. More recently, the authors began to use these models for the analysis of data on intermediate lesions on the pathway to cancer. Such data are available in experimental carcinogenesis studies, in particular in initiation and promotion studies on the mouse skin and the rat liver. If however, quantitative information on intermediate lesions on the pathway to lung cancer were to be come available at some future date, the methods that they have developed for the analysis of initiation-promotion experiments could easily be applied to the analysis of these lesions. The mathematical derivations here are couched in terms of a particular two-mutation model of carcinogenesis. Extension to models postulating more than two mutations is not always straightforward

  13. Complications of CT guided lumbar sympathicolysis: own experience and review of literature

    International Nuclear Information System (INIS)

    Ernst, S.; Heindel, W.; Fischbach, R.; Langen, H.J.; Krahe, T.; Gawenda, M.; Neubauer, S.

    1998-01-01

    Aim: To review the complications of CT guided lumbar sympathicolysis (CTLS) on the basis of our own experience and the available literature. Methods: 241 CTLS were performed by a standard technique according to Haaga's method. Clinical follow-up revealed 4 serious complications; these were analysed and compared with published cases. Results: Amongst our patients there were three fibrotic ureter stenoses and one retroperitoneal abscess. Analysis of the serious complications described in the literature indicates that introduction of CT guided lumbar sympathicolysis has reduced the severity and frequency of complications as compared with surgical and 'blind' procedures. With CTLS, no deaths due to the procedure have been reported in the literature. The results indicate that damage to the ureters can be caused by substances used for the neurolysis. (orig./MG) [de

  14. Initial evaluation of commercial optical CT-based 3D gel dosimeter

    International Nuclear Information System (INIS)

    Islam, K.T.S.; Dempsey, James F.; Ranade, Manisha K.; Maryanski, Marek J.; Low, Daniel A.

    2003-01-01

    We evaluated the OCTOPUS-ONE trade mark sign research laser CT scanner developed and manufactured by MGS Research, Inc. (Madison, CT). The scanner is designed for imaging 3D optical density distributions in BANG registered gels. The scanner operates in a translate-rotate configuration with a single scanning laser beam. The rotating cylindrical gel phantom is immersed in a refractive index matching solution and positioned at the center of a square tank made of plastic and glass. A stationary polarized He-Ne laser beam (633 nm) is reflected from a mirror moving parallel to the tank wall and scans the gel. Another mirror moves synchronously along the opposite side of the tank and collects the transmitted light and sends it to a single stationary silicon photodetector. A filtered backprojection algorithm is used to reconstruct projection data in a plane. The laser-mirrors-detector assembly is mounted on a horizontal platform that moves vertically for slice selection. We have tested the mechanical and optical setup, projection centering on the axis of rotation, linearity, and spatial resolution. We found the optical detector to respond linearly to transmitted light from control samples. The spatial resolution of the scanner was determined by employing a split field resolution technique. We obtained the horizontal and vertical full widths at half maxima of the laser beam intensity profiles as 0.6 and 0.8 mm, respectively. Dose calibration tests of the gel were performed using a nine-field (2x2 cm 2 each) dose pattern irradiated at different dose levels. Finally, we compared gel-derived 2D planar dose distribution against radiochromic film measured dose distribution for both the nine-field and a uniform 5x5 cm 2 field of 6 MV x rays. Very similar dose distributions were observed in gel and radiochromic film except in regions of steep dose gradient and highest dose. A dose normalization of 15.6% was required between the two dosimeters due to differences in overall

  15. Initial use of fast switched dual energy CT for coronary artery disease

    Science.gov (United States)

    Pavlicek, William; Panse, Prasad; Hara, Amy; Boltz, Thomas; Paden, Robert; Yamak, Didem; Licato, Paul; Chandra, Naveen; Okerlund, Darin; Dutta, Sandeep; Bhotika, Rahul; Langan, David

    2010-04-01

    Coronary CT Angiography (CTA) is limited in patients with calcified plaque and stents. CTA is unable to confidently differentiate fibrous from lipid plaque. Fast switched dual energy CTA offers certain advantages. Dual energy CTA removes calcium thereby improving visualization of the lumen and potentially providing a more accurate measure of stenosis. Dual energy CTA directly measures calcium burden (calcium hydroxyapatite) thereby eliminating a separate non-contrast series for Agatston Scoring. Using material basis pairs, the differentiation of fibrous and lipid plaques is also possible. Patency of a previously stented coronary artery is difficult to visualize with CTA due to resolution constraints and localized beam hardening artifacts. Monochromatic 70 keV or Iodine images coupled with Virtual Non-stent images lessen beam hardening artifact and blooming. Virtual removal of stainless steel stents improves assessment of in-stent re-stenosis. A beating heart phantom with 'cholesterol' and 'fibrous' phantom coronary plaques were imaged with dual energy CTA. Statistical classification methods (SVM, kNN, and LDA) distinguished 'cholesterol' from 'fibrous' phantom plaque tissue. Applying this classification method to 16 human soft plaques, a lipid 'burden' may be useful for characterizing risk of coronary disease. We also found that dual energy CTA is more sensitive to iodine contrast than conventional CTA which could improve the differentiation of myocardial infarct and ischemia on delayed acquisitions. These phantom and patient acquisitions show advantages with using fast switched dual energy CTA for coronary imaging and potentially extends the use of CT for addressing problem areas of non-invasive evaluation of coronary artery disease.

  16. How does arm positioning of polytraumatized patients in the initial computed tomography (CT) affect image quality and diagnostic accuracy?

    International Nuclear Information System (INIS)

    Kahn, Johannes; Grupp, Ulrich; Maurer, Martin

    2014-01-01

    Purpose: To evaluate the influence of different arm positions on abdominal image quality during initial whole-body CT (WBCT) in polytraumatized patients and to assess the risk of missing potentially life-threatening injuries due to arm artifacts. Materials and methods: Between July 2011 and February 2013, WBCT scans of 203 patients with arms in the abdominal area during initial WBCT were analyzed. Six different arms-down positions were defined: patients with both (group A)/one arm(s) (group B) down alongside the torso, patients with both (group C)/one arm(s) (group D) crossed in front of the upper abdomen, patients with both (group E)/one arm(s) (group F) crossed in front of the pelvic area. A group of 203 patients with elevated arms beside the head served as a control group. Two observers jointly evaluated image quality of different organ regions using a 4-point scale system. Follow-up examinations (CT scans and/or ultrasound) were analyzed to identify findings missed during initial WBCT due to reduced image quality. Results: Image quality for most of the organ regions analyzed was found to be significantly different among all groups (p < 0.05). Image quality was most severely degraded in group A, followed by groups E and C. Positioning with one arm up resulted in significantly better image quality than both arms down (p < 0.05). Overall, arms-up positioning showed significantly better image quality than arms-down positions (p < 0.05). In one case, liver hemorrhage missed in the initial WBCT because of arm artifacts, was revealed by follow-up CT. Conclusion: In WBCT arms-down positioning significantly degrades abdominal image quality and artifacts might even conceal potentially life-threatening injuries. If the patient's status does not allow elevation of both arms, image quality can benefit from raising at least one arm. Otherwise, arms should be placed in front of the upper abdomen instead of alongside the torso

  17. [Initial experience in robot-assisted colorectal surgery in Mexico].

    Science.gov (United States)

    Villanueva-Sáenz, Eduardo; Ramírez-Ramírez, Moisés Marino; Zubieta-O'Farrill, Gregorio; García-Hernández, Luis

    Colorectal surgery has advanced notably since the introduction of the mechanical suture and the minimally invasive approach. Robotic surgery began in order to satisfy the needs of the patient-doctor relationship, and migrated to the area of colorectal surgery. An initial report is presented on the experience of managing colorectal disease using robot-assisted surgery, as well as an analysis of the current role of this platform. A retrospective study was conducted in order to review five patients with colorectal disease operated using a robot-assisted technique over one year in the initial phase of the learning curve. Gender, age, diagnosis and surgical indication, surgery performed, surgical time, conversion, bleeding, post-operative complications, and hospital stay, were analysed and described. A literature review was performed on the role of robotic assisted surgery in colorectal disease and cancer. The study included 5 patients, 3 men and 2 women, with a mean age of 62.2 years. Two of them were low anterior resections with colorectal primary anastomoses, one of them extended with a loop protection ileostomy, a Frykman-Goldberg procedure, and two left hemicolectomies with primary anastomoses. The mean operating time was 6hours and robot-assisted 4hours 20minutes. There were no conversions and the mean hospital stay was 5 days. This technology is currently being used worldwide in different surgical centres because of its advantages that have been clinically demonstrated by various studies. We report the first colorectal surgical cases in Mexico, with promising results. There is enough evidence to support and recommend the use of this technology as a viable and safe option. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  18. Dual energy CT intracranial angiography: image quality, radiation dose and initial application results

    International Nuclear Information System (INIS)

    Chai Xue; Zhang Longjiang; Lu Guangming; Zhou Changsheng

    2009-01-01

    Objective: To assess the clinical value of dual-energy intracranial CT angiography (CTA). Methods: Forty-one patients suspected of intracranial vascular diseases underwent dual-energy intracranial CT angiography, and 41 patients who underwent conventional subtraction CT were enrolled as the control group. Image quality of intracranial and skull base vessels and radiation dose between dual-energy CTA and conventional subtraction CTA were compared using two independent sample nonparametric test and independent-samples t test, respectively. Prevalence and size of lesions detected by dual-energy CTA and digital subtraction CTA were compared using paired-samples t test and Spearman correlative analysis. Results: The percentage of image quality scored 5 was 70.7% (29/41) for dual-energy CTA and 75.6% (31/41) for conventional subtraction CTA. There was no significant difference between the two groups (Z= -0.455, P=0.650). Image quality of vessels at the skull base in conventional subtraction CTA was superior to that in dual-energy CTA, especially for the petrosal and syphon segment (Z=-4.087, P=0.000). Radiation exposure of dual energy CTA and conventional CTA were (396.54±17.43) and (1090.95±114.29) mGy·cm respectively. Radiation exposure was decreased by 64% (t=-38.52, P=0.000) by dual energy CTA compared with conventional subtraction CTA. Out of the 41 patients, 19 patients were diagnosed as intracranial aneurysm, 2 patients as arteriovenous malformation (AVM), 3 patients with Moya-moya's disease, and the remaining 17 patients with negative results. Nine patients with intracranial aneurysm, 2 patients with AVM, 3 patients with Moya-moya's disease, and 2 patients with negative findings underwent DSA or operation, with concordant findings from both techniques. Diameter of aneurysm neck, long axis and minor axis by dual-energy CTA was (2.90±1.61), (5.23±1.68) and (3.83±1.69) mm, respectively; Diameter of aneurysm neck, long axis and minor axis by DSA was (2.95±1

  19. The PIOTRON: initial performance, preparation and experience with pion therapy

    International Nuclear Information System (INIS)

    Von Essen, C.F.; Blattmann, H.; Crawford, J.F.; Fessenden, P.; Pedroni, E.; Perret, C.; Salzmann, M.; Shortt, K.; Walder, E.

    1982-01-01

    The PIOTRON is a large solid angle superconducting channel built for the use of negative pi-mesons in radiotherapy. The pions are produced by protons of 590 MeV striking a target of molybdenum or beryllium. The pions are divided into 60 channels and deflected twice to enter the treatment volume radially. The momentum and the momentum band for all 60 channels can be chosen and the beam spot of Bragg peak pions at the isocenter of the applicator is a few centimeters in each direction. Dynamic scanning can thus achieve 3-dimensionally shaped treatment volumes. Two different methods are available: the ring scan, using changes of pion range; and the spot scan, involving translation of the patient through the fixed beam spot. Dose distributions of individual and multiple beams were plotted in a cylindrical water phantom. Radiobiological experiments with mammalian cells in gel and with mouse feet were performed. A special beam geometry using a sector of 15 beams was selected for the first treatments of patients with metastatic skin nodules. Six patients were treated. Acute skin reactions were scored and compared with those from orthovoltage therapy with comparable beam geometry. The RBE for 10 fractions is between 1.4 and 1.5. The next step involved treatment of patients inside water-bolus rings in preparation for dynamic therapy. Patients were then treated with the spot scan dynamic mode in the water bolus. The initial responses and reactions are favorable and confirm the feasibility and accuracy of dynamic pion therapy

  20. Initial Experience with ABO-incompatible Live Donor Renal Transplantation

    Directory of Open Access Journals (Sweden)

    Meng-Kun Tsai

    2006-01-01

    Full Text Available The serious shortage of cadaveric organs has prompted the development of ABO-incompatible live donor renal transplantation. We report our experience of the initial two live donor ABO incompatible renal transplants at our hospital. The first patient was a 55-year-old type A female who received a kidney from her AB type husband. The second patient was a 27-year-old type O male who received renal transplantation from his type A father. Preconditioning immunosuppressive therapy in the two patients with tacrolimus, mycophenolate mofetil and methylprednisolone was started 7 days before transplantation. During the period of preconditioning, double filtration plasmapheresis (DFPP was employed to remove anti-A and -B antibodies. Laparoscopic splenectomy and renal transplantation were performed after the anti-donor ABO antibodies were reduced to a titer of 1:4. Rituximab, a humanized monoclonal anti-CD20 antibody, was administered to the second patient due to a rebound in the anti-A antibody titer during the preconditioning period. Under a tacrolimus-based immunosuppressive regimen, both patients recovered very well without any evidence of rejection. Serum creatinine levels were 1.0 and 1.4 mg/dL at 6 and 3 months after transplantation, respectively. These cases illustrate that with new immunosuppressive agents, DFPP and splenectomy, ABO-incompatible renal transplantation can be successfully conducted in end-stage renal disease patients whose only available live donors are blood group incompatible.

  1. Initial Experience with the Machine Protection System for LHC

    CERN Document Server

    Schmidt, Ruediger; Dehning, Bernd; Ferro-Luzzi, Massimiliano; Goddard, Brennan; Lamont, Mike; Siemko, Andrzej; Uythoven, Jan; Wenninger, Jorg; Zerlauth, Markus

    2010-01-01

    For nominal beam parameters at 7 TeV/c each proton beam with a stored energy of 362 MJ threatens to damage accelerator equipment in case of uncontrolled beam loss. These parameters will only be reached after some years of operation, however, a small fraction of this energy is already sufficient to damage accelerator equipment or experiments. The correct functioning of the machine protection systems is vital during the different operational phases already for initial operation. When operating the complex magnet system, with and without beam, safe operation relies on the protection and interlock systems for the superconducting circuits. For safe injection and transfer of the beams from SPS to LHC, transfer line parameters are monitored, beam absorbers must be in the correct position and the LHC must be ready to accept beam. At the end of a fill and in case of failures beams must be properly extracted onto the dump blocks, for some types of failure within less than few hundred microseconds. Safe operation requir...

  2. [Aortic valve preservation in Marfan syndrome. Initial experience].

    Science.gov (United States)

    Forteza, Alberto; Cortina, Jose M; Sánchez, Violeta; Centeno, Jorge; López, M Jesús; Pérez de la Sota, Enrique; Rufilanchas, Juan J

    2007-05-01

    Preservation of the aortic valve using the technique described by David has been shown to be as effective as the Bentall-De Bono procedure. It avoids both the need for long-term anticoagulation and the complications associated with mechanical prostheses. We report our initial experience using this technique in patients with Marfan syndrome. Between April 2004 and April 2006, we used the David reimplantation technique in 40 patients with an aortic root aneurysm. Eighteen patients had Marfan syndrome. Their median age was 29 years (13-55 years). Echocardiography showed that the median diameter of the aortic sinus was 53 mm (46-59 mm). In 17 patients, aortic valve preservation was possible. No patient died during hospitalization and there were no significant complications. On echocardiography at discharge, no patient had greater than grade-II aortic regurgitation. During a median follow-up period of 8 months (1-24 months), one patient died due to rupture of an abdominal aneurysm. The others are all in New York Heart Association class I. Preservation of the aortic valve by means of valve reimplantation produced excellent results. It avoided both the thromboembolic and hemorrhagic complications associated with prostheses and the need for long-term anticoagulation. If reimplanted valves continue to function adequately over the long term, this technique should become the treatment of choice for aneurysms of the ascending aorta in patients with Marfan syndrome.

  3. X-ray strain tensor imaging: FEM simulation and experiments with a micro-CT.

    Science.gov (United States)

    Kim, Jae G; Park, So E; Lee, Soo Y

    2014-01-01

    In tissue elasticity imaging, measuring the strain tensor components is necessary to solve the inverse problem. However, it is impractical to measure all the tensor components in ultrasound or MRI elastography because of their anisotropic spatial resolution. The objective of this study is to compute 3D strain tensor maps from the 3D CT images of a tissue-mimicking phantom. We took 3D micro-CT images of the phantom twice with applying two different mechanical compressions to it. Applying the 3D image correlation technique to the CT images under different compression, we computed 3D displacement vectors and strain tensors at every pixel. To evaluate the accuracy of the strain tensor maps, we made a 3D FEM model of the phantom, and we computed strain tensor maps through FEM simulation. Experimentally obtained strain tensor maps showed similar patterns to the FEM-simulated ones in visual inspection. The correlation between the strain tensor maps obtained from the experiment and the FEM simulation ranges from 0.03 to 0.93. Even though the strain tensor maps suffer from high level noise, we expect the x-ray strain tensor imaging may find some biomedical applications such as malignant tissue characterization and stress analysis inside the tissues.

  4. Dose reduction with adaptive statistical iterative reconstruction for paediatric CT: phantom study and clinical experience on chest and abdomen CT.

    Science.gov (United States)

    Gay, F; Pavia, Y; Pierrat, N; Lasalle, S; Neuenschwander, S; Brisse, H J

    2014-01-01

    To assess the benefit and limits of iterative reconstruction of paediatric chest and abdominal computed tomography (CT). The study compared adaptive statistical iterative reconstruction (ASIR) with filtered back projection (FBP) on 64-channel MDCT. A phantom study was first performed using variable tube potential, tube current and ASIR settings. The assessed image quality indices were the signal-to-noise ratio (SNR), the noise power spectrum, low contrast detectability (LCD) and spatial resolution. A clinical retrospective study of 26 children (M:F = 14/12, mean age: 4 years, range: 1-9 years) was secondarily performed allowing comparison of 18 chest and 14 abdominal CT pairs, one with a routine CT dose and FBP reconstruction, and the other with 30 % lower dose and 40 % ASIR reconstruction. Two radiologists independently compared the images for overall image quality, noise, sharpness and artefacts, and measured image noise. The phantom study demonstrated a significant increase in SNR without impairment of the LCD or spatial resolution, except for tube current values below 30-50 mA. On clinical images, no significant difference was observed between FBP and reduced dose ASIR images. Iterative reconstruction allows at least 30 % dose reduction in paediatric chest and abdominal CT, without impairment of image quality. • Iterative reconstruction helps lower radiation exposure levels in children undergoing CT. • Adaptive statistical iterative reconstruction (ASIR) significantly increases SNR without impairing spatial resolution. • For abdomen and chest CT, ASIR allows at least a 30 % dose reduction.

  5. MR imaging-guided percutaneous cryotherapy for lung tumors: initial experience.

    Science.gov (United States)

    Liu, Shangang; Ren, Ruimei; Liu, Ming; Lv, Yubo; Li, Bin; Li, Chengli

    2014-09-01

    To evaluate prospectively the initial clinical experience of magnetic resonance (MR) imaging-guided percutaneous cryotherapy of lung tumors. MR imaging-guided percutaneous cryotherapy was performed in 21 patients with biopsy-proven lung tumors (12 men, 9 women; age range, 39-79 y). Follow-up consisted of contrast-enhanced chest computed tomography (CT) scan performed at 3-month intervals to assess tumor control; CT scanning was carried out for 12 months or until death. Cryotherapy procedures were successfully completed in all 21 patients. Pneumothorax occurred in 7 (33.3%) of 21 patients. Chest tube placement was required in one (4.8%) case. Hemoptysis was exhibited by 11 (52.4%) patients, and pleural effusion occurred in 6 (28.6%) patients. Other complications were observed in 14 (66.7%) patients. The mean follow-up period was 10.5 months (range, 9-12 mo) in patients who died. At month 12 of follow-up, 7 (33.3%) patients had a complete response to therapy, and 10 (47.6%) patients showed a partial response. In addition, two patients had stable disease, and two patients developed progressive disease; one patient developed a tumor in the liver, and the other developed a tumor in the brain. The 1-year local control rate was 81%, and 1-year survival rate was 90.5%. MR imaging-guided percutaneous cryotherapy appears feasible, effective, and minimally invasive for lung tumors. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.

  6. Dual-energy CT myelography on detection of spontaneous spinal cerebrospinal fluid leaks: initial study

    International Nuclear Information System (INIS)

    Zhang Qiaowei; Wang Dan; Zhang Jinhua; Wang Jin; Zhang Shizheng

    2011-01-01

    Objective: To assess the value of dual-energy computed tomography myelography (CTM) on detecting leaks of cerebrospinal fluid (CSF) in patients with spontaneous intracranial hypotension (SIH). Methods: Six patients with SIH underwent spinal CTM on a 2nd generation dual-source CT with tube voltage set at 100 and 140 kVp (with tin filter). The virtual non-contrast (VNC) and iodine map images were calculated from dual-energy images. The average weighted (AW) CTM images were mixed from two kVp images with mix factor of 0.5. Two radiologists evaluated CSF leak using two sets of images respectively: VNC + iodine map images and AW-CTM images. The results from two reading methods were compared. The level of CSF leaks along the nerve roots, C1-2 retrospinal CSF collections, epidural CSF collections and spinal epidural venous plexus were marked. The consensus about leak sites and CSF collections was made by two radiologists in the third session. Kappa statistics were used to measure the agreement between the two methods. Results: Forty-one leaks were detected using VNC + iodine map images. Forty-three leaks were detected on AW images. The agreement between two methods was excellent (Kappa = 0.997, P<0.01). There were no differences in the detection of C1-2 retrospinal CSF collections (n=2), epidural CSF collections (n=3) or spinal epidural venous plexus (n=1). VNC and iodine map images demonstrated superior visual effects than AW images. Conclusion: Dual-energy CTM can be used to diagnose spontaneous spinal cerebrospinal fluid leaks in SIH patient, (authors)

  7. Clinical usefulness of 18F–FDG PET/CT for initial staging and assessment of treatment efficacy in patients with lymph node tuberculosis

    International Nuclear Information System (INIS)

    Lefebvre, Nicolas; Argemi, Xavier; Meyer, Nicolas; Mootien, Joy; Douiri, Nawal; Sferrazza-Mandala, Stefania; Schramm, Frédéric; Weingertner, Noëlle; Christmann, Daniel; Hansmann, Yves; Imperiale, Alessio

    2017-01-01

    Introduction: Few studies have evaluated the promising role of 18 F–fluoro-2-deoxy-D-glucose positron emission tomography (PET) and PET/computed tomography FDG PET/CT in evaluating and monitoring treatment response in patients with lymph node tuberculosis (LNTB). The aim of this clinical investigation was to assess the clinical usefulness of FDG PET/CT for initial tuberculosis staging and to determine the prognostic value of the decrease of 18 F–FDG uptake during antibiotic treatment in LNTB patients. Methods: We retrospectively reviewed 18 cases of LNTB admitted at a single center from 2004 to 2014. Medical records of patients who underwent two FDG PET/CT (>6 months interval), at initial staging and at the end of therapy were reviewed to determine the impact of FDG PET/CT on initial management of LNTB and response to therapy. Statistical analysis was performed using linear mixed-effects model. Results: Thirteen cases of disseminated LNTB and five cases of localized LNTB were included in the study. Initial FDG PET/CT allowed guided biopsy for initial diagnosis in 5 patients and identified unknown extra-LN TB sites in 9 patients. Visual analysis follow-up of FDG PET/CT showed a complete metabolic response in 9/18 patients (all of whom were cured), a partial response in 7/18 (5 of whom were cured) and no response in 2/18 (all of whom were not cured). The semi-quantitative evaluation of 18F–FDG intensity decrease based on the maximum standardized uptake value (SUVmax), compared to targeted estimated decrease allowed to predict correctly a complete response to treatment in 14/18 cases. Conclusion: FDG PET/CT allows an accurate pre-therapeutic mapping of LNTB and helps for early TB confirmation. The SUVmax follow up is a potential tool for monitoring the treatment response.

  8. Percutaneous MR-guided cryoablation of prostate cancer: initial experience

    International Nuclear Information System (INIS)

    Gangi, Afshin; Tsoumakidou, Georgia; Abdelli, Omar; Buy, Xavier; Mathelin, Michel de; Jacqmin, Didier; Lang, Herve

    2012-01-01

    We report our initial experience and the technical feasibility of transperineal prostate cryoablation under MR guidance. Percutaneous MR-guided cryoablation was performed in 11 patients with prostatic adenocarcinoma contraindicated for surgery (mean age: 72 years, mean Gleason score: 6.45, mean prostate-specific antigen (PSA): 6.21 ng/ml, T1-2c/N0/M0, mean: prostate volume 36.44 ml). Free-hand probe positioning was performed under real-time MR imaging. Four to seven cryoprobes were inserted into the prostate, depending on gland volume. The ice ball was monitored using real-time and high-resolution BLADE multi-planar imaging. Patients were followed at 1, 3, 6, 9 and 12 months after the procedure with serum PSA level and post-ablation MRI. Prostate cryoablation was technically feasible in 10/11 patients. The ice ball was clearly and sharply visualised in all cases as a signal-void area. Mean ice-ball volume was 53.3 ml. Mean follow-up was 15 months (range: 1-25). Mean PSA nadir was 0.33 ng/ml (range: 0.02-0.94 ng/ml). Mean hospitalisation was 5 days (range: 3-13). Complications included a urethro-rectal fistula, urinary infection, transient dysuria and scrotal pain. MR-guided prostate cryoablation is feasible and promising, with excellent monitoring of the ice ball. Future perspectives could include the use of MR guidance for focal prostate cancer cryotherapy. (orig.)

  9. Percutaneous MR-guided cryoablation of prostate cancer: initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Gangi, Afshin; Tsoumakidou, Georgia; Abdelli, Omar; Buy, Xavier [University Hospital of Strasbourg, Department of Interventional Radiology, Strasbourg (France); Mathelin, Michel de [University of Strasbourg, Lsiit, Strasbourg (France); Jacqmin, Didier; Lang, Herve [University Hospital of Strasbourg, Department of Urology, Strasbourg (France)

    2012-08-15

    We report our initial experience and the technical feasibility of transperineal prostate cryoablation under MR guidance. Percutaneous MR-guided cryoablation was performed in 11 patients with prostatic adenocarcinoma contraindicated for surgery (mean age: 72 years, mean Gleason score: 6.45, mean prostate-specific antigen (PSA): 6.21 ng/ml, T1-2c/N0/M0, mean: prostate volume 36.44 ml). Free-hand probe positioning was performed under real-time MR imaging. Four to seven cryoprobes were inserted into the prostate, depending on gland volume. The ice ball was monitored using real-time and high-resolution BLADE multi-planar imaging. Patients were followed at 1, 3, 6, 9 and 12 months after the procedure with serum PSA level and post-ablation MRI. Prostate cryoablation was technically feasible in 10/11 patients. The ice ball was clearly and sharply visualised in all cases as a signal-void area. Mean ice-ball volume was 53.3 ml. Mean follow-up was 15 months (range: 1-25). Mean PSA nadir was 0.33 ng/ml (range: 0.02-0.94 ng/ml). Mean hospitalisation was 5 days (range: 3-13). Complications included a urethro-rectal fistula, urinary infection, transient dysuria and scrotal pain. MR-guided prostate cryoablation is feasible and promising, with excellent monitoring of the ice ball. Future perspectives could include the use of MR guidance for focal prostate cancer cryotherapy. (orig.)

  10. Dose reduction with adaptive statistical iterative reconstruction for paediatric CT: phantom study and clinical experience on chest and abdomen CT

    Energy Technology Data Exchange (ETDEWEB)

    Gay, F.; Lasalle, S.; Neuenschwander, S.; Brisse, H.J. [Institut Curie, Imaging Department, Paris (France); Pavia, Y.; Pierrat, N. [Institut Curie, Medical Physics Department, Paris (France)

    2014-01-15

    To assess the benefit and limits of iterative reconstruction of paediatric chest and abdominal computed tomography (CT). The study compared adaptive statistical iterative reconstruction (ASIR) with filtered back projection (FBP) on 64-channel MDCT. A phantom study was first performed using variable tube potential, tube current and ASIR settings. The assessed image quality indices were the signal-to-noise ratio (SNR), the noise power spectrum, low contrast detectability (LCD) and spatial resolution. A clinical retrospective study of 26 children (M:F = 14/12, mean age: 4 years, range: 1-9 years) was secondarily performed allowing comparison of 18 chest and 14 abdominal CT pairs, one with a routine CT dose and FBP reconstruction, and the other with 30 % lower dose and 40 % ASIR reconstruction. Two radiologists independently compared the images for overall image quality, noise, sharpness and artefacts, and measured image noise. The phantom study demonstrated a significant increase in SNR without impairment of the LCD or spatial resolution, except for tube current values below 30-50 mA. On clinical images, no significant difference was observed between FBP and reduced dose ASIR images. Iterative reconstruction allows at least 30 % dose reduction in paediatric chest and abdominal CT, without impairment of image quality. (orig.)

  11. Dose reduction with adaptive statistical iterative reconstruction for paediatric CT: phantom study and clinical experience on chest and abdomen CT

    International Nuclear Information System (INIS)

    Gay, F.; Lasalle, S.; Neuenschwander, S.; Brisse, H.J.; Pavia, Y.; Pierrat, N.

    2014-01-01

    To assess the benefit and limits of iterative reconstruction of paediatric chest and abdominal computed tomography (CT). The study compared adaptive statistical iterative reconstruction (ASIR) with filtered back projection (FBP) on 64-channel MDCT. A phantom study was first performed using variable tube potential, tube current and ASIR settings. The assessed image quality indices were the signal-to-noise ratio (SNR), the noise power spectrum, low contrast detectability (LCD) and spatial resolution. A clinical retrospective study of 26 children (M:F = 14/12, mean age: 4 years, range: 1-9 years) was secondarily performed allowing comparison of 18 chest and 14 abdominal CT pairs, one with a routine CT dose and FBP reconstruction, and the other with 30 % lower dose and 40 % ASIR reconstruction. Two radiologists independently compared the images for overall image quality, noise, sharpness and artefacts, and measured image noise. The phantom study demonstrated a significant increase in SNR without impairment of the LCD or spatial resolution, except for tube current values below 30-50 mA. On clinical images, no significant difference was observed between FBP and reduced dose ASIR images. Iterative reconstruction allows at least 30 % dose reduction in paediatric chest and abdominal CT, without impairment of image quality. (orig.)

  12. Additional value of integrated PET/CT over PET alone in the initial staging and follow up of head and neck malignancy

    International Nuclear Information System (INIS)

    Ishikita, Tomohiro; Oriuchi, Noboru; Higuchi, Tetsuya

    2010-01-01

    Clinical application of fluorodeoxyglucose (FDG)-positron emission tomography (PET) in head and neck cancer includes identification of metastases, unknown primary head and neck malignancy, or second primary carcinoma, and also recurrent tumor after treatment. In this study, the additional value of PET/CT fusion images over PET images alone was evaluated in patients with initial staging and follow up of head and neck malignancy. Forty patients with suspected primary head and neck malignancy and 129 patients with suspected relapse after treatment of head and neck malignancy were included. FDG-PET/CT study was performed after the intravenous administration of FDG (5 MBq/kg). Target of evaluation was set at primary tumor, cervical lymph node, and whole body. PET images and PET with CT fusion images were compared. Sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Results of PET and PET/CT were compared with postoperative histopathological examination, and case by case comparison of PET and PET/CT results for each region was performed. The additional value of CT images over PET only images was assessed. Statistical differences in sensitivity and specificity were evaluated. In the comparative evaluation of 507 targets by PET alone and PET/CT, 401 targets showed agreement of the results. Of the 106 discordant targets, 103 showed a positive result on PET alone and negative result on PET/CT. These results showed a significant difference (p<0.01). Sensitivity of PET/CT was slightly higher than that of PET without statistical significance, while specificity of PET/CT was significantly higher than that of PET alone (Initial Staging: 90.5% vs. 62.2%, p<0.01; Follow up: 97.2% vs. 74.4%, p<0.01). In Fisher's direct probability test, a significant difference was noted in the sensitivity (Initial staging: 91.3% vs. 87.0%, p<0.01; Follow up: 93.9% vs. 91.4%, p<0.01). Combined PET/CT showed improved diagnostic

  13. CT Colonography: Role of a second reader CAD paradigm in the initial training of radiologists

    International Nuclear Information System (INIS)

    Neri, Emanuele; Faggioni, Lorenzo; Regge, Daniele; Vagli, Paola; Turini, Francesca; Cerri, Francesca; Picano, Eugenia; Giusti, Sabina; Bartolozzi, Carlo

    2011-01-01

    Purpose: To evaluate the influence of CAD for the evaluation of CT colonography (CTC) datasets by inexperienced readers during the attendance of a dedicated hands-on training course. Method and materials: Twenty-seven radiologists inexperienced in CTC (11 with no CTC training at all, 16 having previously reviewed no more than 10 CTC cases overall) attended a hands-on training course based on direct teaching on fifteen workstations (four Advantage Windows 4.4 with Colon VCAR software, GE; six CADCOLON, Im3D; five ColonScreen (Toshiba/Voxar) with ColonCAD TM API, Medicsight). During the course, readers were instructed to analyze 26 CTC cases including 38 colonic lesions obtained through low-dose MDCT acquisitions, consisting of 12 polyps sized less than 6 mm, 9 polyps sized between 6 and 10 mm, 12 polyps sized between 11 mm and 30 mm, and 5 colonic masses sized >3 cm. CTC images were reviewed by each reader both in 2D and 3D mode, respectively by direct evaluation of native axial images and MPR reconstructions, and virtual endoscopy or dissected views. Each reader had 15 min time for assessing each dataset without CAD, after which results were compared with those provided by CAD software. Global rater sensitivity for each lesion size before and after CAD usage was compared by means of two-tailed Student's t test, while sensitivity of each single reader before and after CAD usage was assessed with the McNemar test. Results: For lesions sized 30 mm, sensitivity before CAD-assisted reading was 0.3556 ± 0.3105 and did not change after CAD usage (p = 1). Sensitivity of each single rater did not significantly differ before and after CAD for any lesion size category (McNemar test, p > 0.05). Specificity was not significantly different before and after CAD for any lesion size (>96% for all size categories). Conclusion: CAD usage led to increased overall sensitivity of inexperienced readers for all polyps sizes, except for lesions >30 mm, but sensitivity of individual raters

  14. Initial investigation of 18F-NaF PET/CT for identification of vertebral sites amenable to surgical revision after spinal fusion surgery

    International Nuclear Information System (INIS)

    Quon, Andrew; Iagaru, Andrei; Dodd, Robert; Abreu, Marcelo Rodrigues de; Sprinz, Clarice; Hennemann, Sergio; Alves Neto, Jose Maria

    2012-01-01

    A pilot study was performed in patients with recurrent back pain after spinal fusion surgery to evaluate the ability of 18 F-NaF PET/CT imaging to correctly identify those requiring surgical intervention and to locate a site amenable to surgical intervention. In this prospective study 22 patients with recurrent back pain after spinal surgery and with equivocal findings on physical examination and CT were enrolled for evaluation with 18 F-NaF PET/CT. All PET/CT images were prospectively reviewed with the primary objective of identifying or ruling out the presence of lesions amenable to surgical intervention. The PET/CT results were then validated during surgical exploration or clinical follow-up of at least 15 months. Abnormal 18 F-NaF foci were found in 16 of the 22 patients, and surgical intervention was recommended. These foci were located at various sites: screws, cages, rods, fixation hardware, and bone grafts. In 6 of the 22 patients no foci requiring surgical intervention were found. Validation of the results by surgery (15 patients) or on clinical follow-up (7 patients) showed that 18 F-NaF PET/CT correctly predicted the presence of an abnormality requiring surgical intervention in 15 of 16 patients and was falsely positive in 1 of 16. In this initial investigation, 18 F-NaF PET/CT imaging showed potential utility for evaluation of recurrent symptoms after spinal fusion surgery by identifying those patients requiring surgical management. (orig.)

  15. A dedicated cone-beam CT system for musculoskeletal extremities imaging: Design, optimization, and initial performance characterization

    International Nuclear Information System (INIS)

    Zbijewski, W.; De Jean, P.; Prakash, P.; Ding, Y.; Stayman, J. W.; Packard, N.; Senn, R.; Yang, D.; Yorkston, J.; Machado, A.; Carrino, J. A.; Siewerdsen, J. H.

    2011-01-01

    Purpose: This paper reports on the design and initial imaging performance of a dedicated cone-beam CT (CBCT) system for musculoskeletal (MSK) extremities. The system complements conventional CT and MR and offers a variety of potential clinical and logistical advantages that are likely to be of benefit to diagnosis, treatment planning, and assessment of therapy response in MSK radiology, orthopaedic surgery, and rheumatology. Methods: The scanner design incorporated a host of clinical requirements (e.g., ability to scan the weight-bearing knee in a natural stance) and was guided by theoretical and experimental analysis of image quality and dose. Such criteria identified the following basic scanner components and system configuration: a flat-panel detector (FPD, Varian 3030+, 0.194 mm pixels); and a low-power, fixed anode x-ray source with 0.5 mm focal spot (SourceRay XRS-125-7K-P, 0.875 kW) mounted on a retractable C-arm allowing for two scanning orientations with the capability for side entry, viz. a standing configuration for imaging of weight-bearing lower extremities and a sitting configuration for imaging of tensioned upper extremity and unloaded lower extremity. Theoretical modeling employed cascaded systems analysis of modulation transfer function (MTF) and detective quantum efficiency (DQE) computed as a function of system geometry, kVp and filtration, dose, source power, etc. Physical experimentation utilized an imaging bench simulating the scanner geometry for verification of theoretical results and investigation of other factors, such as antiscatter grid selection and 3D image quality in phantom and cadaver, including qualitative comparison to conventional CT. Results: Theoretical modeling and benchtop experimentation confirmed the basic suitability of the FPD and x-ray source mentioned above. Clinical requirements combined with analysis of MTF and DQE yielded the following system geometry: a ∼55 cm source-to-detector distance; 1.3 magnification; a 20

  16. Radiolysis of Fricke solution: initial experiments with the pelletron facility

    International Nuclear Information System (INIS)

    Sharma, S.B.; Rao, B.S.M.

    1994-01-01

    Experimental details of heavy ion irradiation of aqueous solutions using the Nuclear Science Centre (NSC) pelletron facility and the initial results from the radiolysis of Fricke solution using oxygen-16 ions are reported. (author). 4 refs., 1 fig

  17. 18F-FDG PET/CT in gastric MALT lymphoma: a bicentric experience

    Energy Technology Data Exchange (ETDEWEB)

    Albano, Domenico; Bertoli, Mattia [Nuclear Medicine, Spedali Civili Brescia, Brescia (Italy); University Milano-Bicocca, Milan (Italy); Ferro, Paola [University Milano-Bicocca, Milan (Italy); Fallanca, Federico; Gianolli, Luigi; Picchio, Maria [IRCCS San Raffaele Scientific Institute, Department of Nuclear Medicine, Milan (Italy); Giubbini, Raffaele; Bertagna, Francesco [University of Brescia and Spedali Civili Brescia, Nuclear Medicine, Brescia (Italy)

    2017-04-15

    The role of 18F-FDG-PET/CT in evaluating gastric MALT lymphoma is still controversial. In the literature the detection rate of 18F-FDG-PET/CT in patients with gastric MALT lymphoma is variable, and the reason for this heterogeneity is not still clear. Our aim was to investigate the particular metabolic behavior of these lymphoma. Sixty-nine patients (26 female, 43 male) with histologically confirmed gastric MALT lymphoma who underwent a 18F-FDG-PET/CT for initial staging from two centers were included. The PET images were analyzed visually and semi-quantitatively by measuring the maximum standardized uptake value (SUVmax), lesion-to-liver SUVmax ratio, and lesion-to-blood pool SUVmax ratio and compared with Ann Arbor stage, epidemiological (age, sex), histological (presence of gastritis, ulcer, H. pylori infection, plasmacytic differentiation, Ki-67 index), and morphological (tumor size, superficial lesions or mass-forming) characteristics. Thirty-six patients (52 %) had positive PET/CT (average SUVmax was 9±6.7; lesion-to-liver SUVmax ratio 3.7±2.6, lesion-to-blood pool SUVmax ratio 4.8±3.3) at the corresponding gastric lesion; the remaining 33 were not 18F-FDG-avid. In the univariate analysis, 18F-FDG avidity was significantly associated with morphological features (mass forming p<0.001 and high maximum diameter p<0.001), Ann Arbor stage (p=0.010), and Ki67 index (p<0.001) and not correlated with age, sex, presence of gastritis, ulcer, Helicobacter pylori infection, and plasmacytic differentiation. In the multivariate analysis, the correlations with gross morphological appearance, Ann Arbor stage, and Ki-67 score were confirmed. SUVmax, lesion-to-liver SUVmax ratio, and lesion-to-blood pool SUVmax ratio correlated significantly only with Ki67 index (p=0.047; p=0.012; p=0.042). 18F-FDG avidity was noted in 52 % of gastric MALT lymphoma and this avidity is correlated with gross morphological characteristics, tumor stage, and Ki-67 index. SUVmax, lesion

  18. 18F-FDG PET/CT in gastric MALT lymphoma: a bicentric experience

    International Nuclear Information System (INIS)

    Albano, Domenico; Bertoli, Mattia; Ferro, Paola; Fallanca, Federico; Gianolli, Luigi; Picchio, Maria; Giubbini, Raffaele; Bertagna, Francesco

    2017-01-01

    The role of 18F-FDG-PET/CT in evaluating gastric MALT lymphoma is still controversial. In the literature the detection rate of 18F-FDG-PET/CT in patients with gastric MALT lymphoma is variable, and the reason for this heterogeneity is not still clear. Our aim was to investigate the particular metabolic behavior of these lymphoma. Sixty-nine patients (26 female, 43 male) with histologically confirmed gastric MALT lymphoma who underwent a 18F-FDG-PET/CT for initial staging from two centers were included. The PET images were analyzed visually and semi-quantitatively by measuring the maximum standardized uptake value (SUVmax), lesion-to-liver SUVmax ratio, and lesion-to-blood pool SUVmax ratio and compared with Ann Arbor stage, epidemiological (age, sex), histological (presence of gastritis, ulcer, H. pylori infection, plasmacytic differentiation, Ki-67 index), and morphological (tumor size, superficial lesions or mass-forming) characteristics. Thirty-six patients (52 %) had positive PET/CT (average SUVmax was 9±6.7; lesion-to-liver SUVmax ratio 3.7±2.6, lesion-to-blood pool SUVmax ratio 4.8±3.3) at the corresponding gastric lesion; the remaining 33 were not 18F-FDG-avid. In the univariate analysis, 18F-FDG avidity was significantly associated with morphological features (mass forming p<0.001 and high maximum diameter p<0.001), Ann Arbor stage (p=0.010), and Ki67 index (p<0.001) and not correlated with age, sex, presence of gastritis, ulcer, Helicobacter pylori infection, and plasmacytic differentiation. In the multivariate analysis, the correlations with gross morphological appearance, Ann Arbor stage, and Ki-67 score were confirmed. SUVmax, lesion-to-liver SUVmax ratio, and lesion-to-blood pool SUVmax ratio correlated significantly only with Ki67 index (p=0.047; p=0.012; p=0.042). 18F-FDG avidity was noted in 52 % of gastric MALT lymphoma and this avidity is correlated with gross morphological characteristics, tumor stage, and Ki-67 index. SUVmax, lesion

  19. MR imaging-guided cryoablation of metastatic brain tumours: initial experience in six patients

    International Nuclear Information System (INIS)

    Li, Chengli; Wu, Lebin; Song, Jiqing; Liu, Ming; Lv, Yubo; Sequeiros, Roberto Blanco

    2010-01-01

    The objective was to evaluate the initial experience and safety of magnetic resonance imaging (MRI)-guided transcranial cryoablation in cystic metastatic brain tumours. Seven cystic metastatic brain tumours in six patients were treated with cryoablation. The approval from the local ethics committee and individual patient consent were acquired before the study. Before the procedure the tumours were detected with conventional CT or MRI. The procedure was performed under local anaesthesia and conscious sedation. A 0.23-T open MRI system with optical tracking was used for procedural planning, instrument guidance and procedural monitoring of the ice ball formation. An MR-compatible, argon-based cryoablation system was used. The schedule of follow-up imaging ranged from 12 days to 12 months. Seven treatment sessions were performed. All the cryoprobes were successfully inserted into the target with one pass. All the patients tolerated the procedure well without experiencing any neurological deficits during the treatment phase or during the immediate post-treatment period. One patient died 12 days after cryoablation. MR-guided and monitored metastasis brain tumour cryoablation is technically feasible and may represent an alternative treatment in selected patients. (orig.)

  20. Analogue experiment of the crustal deformation by X-ray CT; X sen CT wo mochiita chikaku no henkei no analogue jikken

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Y.; Shi, B; Murakami, Y. [Geological Survey of Japan, Tsukuba (Japan)

    1997-05-27

    This paper reports a predictive result on a deformation experiment on sand beds using an X-ray computerized tomography (CT) equipment. The X-ray CT is a method to perform the following processes: X-rays are irradiated on a sample; decayed intensity data are measured along ray paths of the permeated X-rays; the data are inverted by using the Fourier transform; and spatial distribution of the coefficient of X-ray absorption inside the sample is acquired as a gray scale image. The deformation experiment was carried by putting sand into an acrylic container to a depth of 2 cm and manually pressing a plate in the horizontal direction. Sand blocks make a relative motion along a specific plane when they are deformed, but it was not possible to recognize faults clearly by naked eyes. Upon completion of the deformation, the experimental device was placed on the CT equipment to acquire images of the two-dimensional cross section. The higher the X-ray absorption coefficient, the brighter the picture elements. It can be seen that three inversed faults have been imaged clearly. Therefore, this equipment was verified usable as an effective observation equipment for an analogue deformation experiment. 4 refs., 2 figs.

  1. Virtual planning of dental implant placement using CT double scan-technique - own experience

    International Nuclear Information System (INIS)

    Wojciechowski, W.; Urbanik, A.; Kownacki, P.; Kownacki, S.

    2007-01-01

    The correctness of CT performed with the use of a double-scan technique is the basis for achieving proper quality of 3D reconstructions of the maxilla or mandible and subsequent virtual planning of dental implant placement. The aim of this study was the presentation of the methodology of computed tomography scanning and own experience with the use of the double-scan technique. The study group included 26 individuals who underwent MDCT with a double-scan technique using a MDCT scanner SOMATOM Sensation (Siemens, Germany). The parameters of the examination: slice-collimation 10 x 0.75 mm, slice-thickness 0.75 mm. The first CT scan in the procedure was the scan of the patient wearing a radiological prosthesis and occlusal index, which was followed by a separate scan of the radiological prosthesis. These two CT scans were copied and transferred to PC with Procera Software program (Nobel Biocare, Sweden) where dental implant placement was virtually planned. In all 26 patients, precise three-dimensional reconstructions of the anatomical structure were obtained. In 11 patients, on the basis of the virtual planning, the implant placement was performed, 5 patients were referred to preparatory procedures, that is, restoration of the alveolar process, otolaryngological treatment of the maxillary sinuses. The remaining 10 patients did not qualify to the procedure because of unfavorable anatomical ideation's. Correct computed tomography with double-scan technique enables virtual planning of dental implant placement, on the basis of which the real procedure of implantation can be performed. (author)

  2. Radiation dose levels in pediatric chest CT: experience in 499 children evaluated with dual-source single-energy CT

    Energy Technology Data Exchange (ETDEWEB)

    Martine, Remy-Jardin; Colas, Lucie; Jean-Baptiste, Faivre; Remy, Jacques [CHU Lille (EA 2694) University of Lille, Department of Thoracic Imaging, Hospital Calmette, Lille (France); Santangelo, Teresa [CHU Lille (EA 2694) University of Lille, Department of Thoracic Imaging, Hospital Calmette, Lille (France); Bambino Gesu Children' s Hospital, Department of Imaging, Rome (Italy); Duhamel, Alain [University of Lille (EA 2694), Department of Biostatistics, CHU Lille, Lille (France); Deschildre, Antoine [CHU Lille - University of Lille, Department of Pediatric Pulmonology, Lille (France)

    2017-02-15

    The availability of dual-source technology has introduced the possibility of scanning children at lower kVp with a high-pitch mode, combining high-speed data acquisition and high temporal resolution. To establish the radiation dose levels of dual-source, single-energy chest CT examinations in children. We retrospectively recorded the dose-length product (DLP) of 499 consecutive examinations obtained in children <50 kg, divided into five weight groups: group 1 (<10 kg, n = 129); group 2 (10-20 kg, n = 176); group 3 (20-30 kg, n = 99), group 4 (30-40 kg, n = 58) and group 5 (40-49 kg, n = 37). All CT examinations were performed with high temporal resolution (75 ms), a high-pitch mode and a weight-adapted selection of the milliamperage. CT examinations were obtained at 80 kVp with a milliamperage ranging between 40 mAs and 90 mAs, and a pitch of 2.0 (n = 162; 32.5%) or 3.0 (n = 337; 67.5%). The mean duration of data acquisition was 522.8 ± 192.0 ms (interquartile range 390 to 610; median 490). In the study population, the mean CT dose index volume (CTDIvol{sub 32}) was 0.83 mGy (standard deviation [SD] 0.20 mGy; interquartile range 0.72 to 0.94; median 0.78); the mean DLP{sub 32} was 21.4 mGy.cm (SD 9.1 mGy.cm; interquartile range 15 to 25; median 19.0); and the mean size-specific dose estimate (SSDE) was 1.7 mGy (SD 0.4 mGy; interquartile range 1.5 to 1.9; median 1.7). The DLP{sub 32}, CTDI{sub vol32} and SSDE were found to be statistically significant in the five weight categories (P < 0.0001). This study establishes the radiation dose levels for dual-source, single-kVp chest CT from a single center. In the five weight categories, the median values varied 15-37 mGy.cm for the DLP{sub 32}, 0.78-1.25 mGy for the CTDI{sub vol32} and 1.6-2.1 mGy for the SSDE. (orig.)

  3. Radiation dose levels in pediatric chest CT: experience in 499 children evaluated with dual-source single-energy CT

    International Nuclear Information System (INIS)

    Martine, Remy-Jardin; Colas, Lucie; Jean-Baptiste, Faivre; Remy, Jacques; Santangelo, Teresa; Duhamel, Alain; Deschildre, Antoine

    2017-01-01

    The availability of dual-source technology has introduced the possibility of scanning children at lower kVp with a high-pitch mode, combining high-speed data acquisition and high temporal resolution. To establish the radiation dose levels of dual-source, single-energy chest CT examinations in children. We retrospectively recorded the dose-length product (DLP) of 499 consecutive examinations obtained in children <50 kg, divided into five weight groups: group 1 (<10 kg, n = 129); group 2 (10-20 kg, n = 176); group 3 (20-30 kg, n = 99), group 4 (30-40 kg, n = 58) and group 5 (40-49 kg, n = 37). All CT examinations were performed with high temporal resolution (75 ms), a high-pitch mode and a weight-adapted selection of the milliamperage. CT examinations were obtained at 80 kVp with a milliamperage ranging between 40 mAs and 90 mAs, and a pitch of 2.0 (n = 162; 32.5%) or 3.0 (n = 337; 67.5%). The mean duration of data acquisition was 522.8 ± 192.0 ms (interquartile range 390 to 610; median 490). In the study population, the mean CT dose index volume (CTDIvol 32 ) was 0.83 mGy (standard deviation [SD] 0.20 mGy; interquartile range 0.72 to 0.94; median 0.78); the mean DLP 32 was 21.4 mGy.cm (SD 9.1 mGy.cm; interquartile range 15 to 25; median 19.0); and the mean size-specific dose estimate (SSDE) was 1.7 mGy (SD 0.4 mGy; interquartile range 1.5 to 1.9; median 1.7). The DLP 32 , CTDI vol32 and SSDE were found to be statistically significant in the five weight categories (P < 0.0001). This study establishes the radiation dose levels for dual-source, single-kVp chest CT from a single center. In the five weight categories, the median values varied 15-37 mGy.cm for the DLP 32 , 0.78-1.25 mGy for the CTDI vol32 and 1.6-2.1 mGy for the SSDE. (orig.)

  4. Integrated FDG-PET/CT for detection, therapy monitoring and follow-up of granulocytic sarcoma. Initial results

    Energy Technology Data Exchange (ETDEWEB)

    Aschoff, Philip; Werner, M.K.; Lichy, M.; Pfannenberg, C. [Dept. of Diagnostic and Interventional Radiology, Univ. Hospital, Eberhard-Karls-Univ. Tuebingen (Germany); Haentschel, M.; Vogel, W. [Dept. of Internal Medicine, Univ. Hospital, Eberhard-Karls-Univ. Tuebingen (Germany); Oeksuez, M. [Dept. of Nuclear Medicine, Univ. Hospital, Eberhard-Karls-Univ. Tuebingen (Germany)

    2009-07-01

    Granulocytic sarcomas (GS) are rare extramedullary manifestations of myeloid or lymphoblastic leukaemia. Laboratory examinations are of limited use for diagnosis of extramedullary disease. Radiological imaging based on morphology is challenging. To date, the possible role of FDG-PET/CT as a method for combined metabolic and morphologic imaging is unclear. We present a series of 10 patients to evaluate the potential role of FDG-PET/CT in the management of GS. Patients, materials, methods: a retrospective evaluation of 18 FDG-PET/CT exams in 10 patients with histologically proven GS was performed. All scans included a contrast enhanced CT. The FDG uptake of GS was analyzed and the sensitivity of lesion detection was compared to PET and CT alone. The changes in FDG uptake after therapy were compared to morphological changes detected by CT and follow-up/clinical outcome. Results: 52 untreated or recurrent GS lesions were detected by FDG-PET/CT and all showed an increased FDG uptake with a mean SUVmax and SUVavg of 5.1 and 3.4, respectively. GS was multifocal in 8/10 patients. Combined PET/CT avoided 5 false positive findings compared to PET alone and 13 false negative findings and 1 false positive compared to CT alone. Changes in FDG uptake after therapy correlated with clinical outcome and were more reliable than CT assessment alone. PET/CT identified recurrent GS in 3 patients. Conclusion: viable GS are FDG-avid. Using this metabolic information and morphologic CT criteria, combined FDG-PET/CT was more accurate in lesion detection than FDG-PET or CT alone. Changes in FDG uptake after therapy might be a useful additional parameter for therapy monitoring. Therefore, FDG-PET/CU appears to be a promising diagnostic and monitoring tool in the management of patients with GS. (orig.)

  5. Automatic localization of landmark sets in head CT images with regression forests for image registration initialization

    Science.gov (United States)

    Zhang, Dongqing; Liu, Yuan; Noble, Jack H.; Dawant, Benoit M.

    2016-03-01

    Cochlear Implants (CIs) are electrode arrays that are surgically inserted into the cochlea. Individual contacts stimulate frequency-mapped nerve endings thus replacing the natural electro-mechanical transduction mechanism. CIs are programmed post-operatively by audiologists but this is currently done using behavioral tests without imaging information that permits relating electrode position to inner ear anatomy. We have recently developed a series of image processing steps that permit the segmentation of the inner ear anatomy and the localization of individual contacts. We have proposed a new programming strategy that uses this information and we have shown in a study with 68 participants that 78% of long term recipients preferred the programming parameters determined with this new strategy. A limiting factor to the large scale evaluation and deployment of our technique is the amount of user interaction still required in some of the steps used in our sequence of image processing algorithms. One such step is the rough registration of an atlas to target volumes prior to the use of automated intensity-based algorithms when the target volumes have very different fields of view and orientations. In this paper we propose a solution to this problem. It relies on a random forest-based approach to automatically localize a series of landmarks. Our results obtained from 83 images with 132 registration tasks show that automatic initialization of an intensity-based algorithm proves to be a reliable technique to replace the manual step.

  6. Informal Science: Family Education, Experiences, and Initial Interest in Science

    Science.gov (United States)

    Dabney, Katherine P.; Tai, Robert H.; Scott, Michael R.

    2016-01-01

    Recent research and public policy have indicated the need for increasing the physical science workforce through development of interest and engagement with informal and formal science, technology, engineering, and mathematics experiences. This study examines the association of family education and physical scientists' informal experiences in…

  7. CT colonography: accuracy of initial interpretation by radiographers in routine clinical practice

    International Nuclear Information System (INIS)

    Burling, D.; Wylie, P.; Gupta, A.; Illangovan, R.; Muckian, J.; Ahmad, R.; Marshall, M.; Taylor, S.A.

    2010-01-01

    Aim: To investigate performance of computed-assisted detection (CAD)-assisted radiographers interpreting computed tomography colonography (CTC) in routine practice. Materials and methods: Three hundred and three consecutive symptomatic patients underwent CTC. Examinations were double-read by trained radiographers using primary two-dimensional/three-dimensional (2D/3D) analysis supplemented by 'second reader' CAD. Radiographers recorded colonic neoplasia, interpretation times, and patient management strategy code (S0, inadequate; S1, normal; S2, 6-9 mm polyp; S3, ≥10 mm polyp; S4, cancer; S5, diverticular stricture) for each examination. Strategies were compared to the reference standard using kappa statistic, interpretation times using paired t-test, learning curves using logistic regression and Pearson's correlation coefficient. Results: Of 303 examinations, 69 (23%) were abnormal. CAD-assisted radiographers detected 17/17 (100%) cancers, 21/28 (72%) polyps ≥10 mm and 42/60 (70%) 6-9 mm polyps. The overall agreement between radiographers and the reference management strategy was good (kappa 0.72; CI: 0.65, 0.78) with agreement for S1 strategy in 189/211 (90%) exams; S2 in 19/27 (70%); S3 in 12/19 (63%); S4 in 17/17 (100%); S5 in 5/6 (83%). The mean interpretation time was 17 min (SD = 11) compared with 8 min (SD = 3.5) for radiologists. There was no learning curve for recording correct strategies (OR 0.88; p = 0.12) but a significant reduction in interpretation times, mean 14 and 31 min (last/first 50 exams; -0.46; p < 0.001). Conclusion: Routine CTC interpretation by radiographers is effective for initial triage of patients with cancer, but independent reporting is currently not recommended.

  8. Analysis of the truth loading conditions of a austenitic CT specimen during a SCC experiment

    International Nuclear Information System (INIS)

    Marie, S.; Guerre, C.; Herms, E.

    2012-01-01

    With the aim to investigate the influence of strain hardening on the stainless steels susceptibility to stress corrosion cracking, tests were conducted in PWR environment on CT specimens, taken from a 316L stainless steel sheet cold rolled to 40% in thickness reduction. The initial cracks obtained by the fatigue pre-cracking have an atypical 'V' shape with smaller propagation in the center of the CT thickness compared to nominal propagation observed at both sides. The initial explanation was to consider a stress intensity factor derived from classical reference solution on the basis of a straight crack front, and considering the local value of the crack depth in the equation. This assumption raised several problems analyses in this paper. This particular shape of the initial defect may be related to several factors, and partly to the 40% cold rolling. It is likely that the hardening is not uniform, with a higher rate at the specimen sides than in the central area. In addition, significant residual stresses due to the gradient of mechanical properties are observed. Due to the high rate of work hardening by rolling of the sheet metal, a gradient of the mechanical properties through the thickness was determined, and the residual stresses profile induced by this process was measured. The variations obtained are consistent with each other: the material is more hardened in the vicinity of specimen surface and residual stresses are compressive in nature in the central part of the specimen and of tensile type on the flanks. All these data were firstly considered in order to assess their role regarding the particular form of the initial crack front obtained after fatigue: the 3D finite element calculations taking into account the true shape of the crack front demonstrate the relationship between the characteristics of the experimental crack front obtained after fatigue pre-cracking and the residual stresses. Moreover, from the residual stresses measured on the plate where

  9. Initial clinical results for breath-hold CT-based processing of respiratory-gated PET acquisitions

    International Nuclear Information System (INIS)

    Fin, Loic; Daouk, Joel; Morvan, Julie; Esper, Isabelle El; Saidi, Lazhar; Meyer, Marc-Etienne; Bailly, Pascal

    2008-01-01

    Respiratory motion causes uptake in positron emission tomography (PET) images of chest structures to spread out and misregister with the CT images. This misregistration can alter the attenuation correction and thus the quantisation of PET images. In this paper, we present the first clinical results for a respiratory-gated PET (RG-PET) processing method based on a single breath-hold CT (BH-CT) acquisition, which seeks to improve diagnostic accuracy via better PET-to-CT co-registration. We refer to this method as ''CT-based'' RG-PET processing. Thirteen lesions were studied. Patients underwent a standard clinical PET protocol and then the CT-based protocol, which consists of a 10-min List Mode RG-PET acquisition, followed by a shallow end-expiration BH-CT. The respective performances of the CT-based and clinical PET methods were evaluated by comparing the distances between the lesions' centroids on PET and CT images. SUV MAX and volume variations were also investigated. The CT-based method showed significantly lower (p=0.027) centroid distances (mean change relative to the clinical method =-49%; range =-100% to 0%). This led to higher SUV MAX (mean change =+33%; range =-4% to 69%). Lesion volumes were significantly lower (p=0.022) in CT-based PET volumes (mean change =-39%: range =-74% to -1%) compared with clinical ones. A CT-based RG-PET processing method can be implemented in clinical practice with a small increase in radiation exposure. It improves PET-CT co-registration of lung lesions and should lead to more accurate attenuation correction and thus SUV measurement. (orig.)

  10. Hawadith Street Initiative: A unique Sudanese childhood charity experience.

    Science.gov (United States)

    Ahmed, Awad Mohamed; A-Rahman, Nada Hassan Ahmed

    2015-01-01

    Due to escalating conflicts and resultant economic constraints, different social services in low income and low-middle income countries have witnessed a decline in its standards, and increase in the costs. This situation has led to emergence of large numbers of patients and their families who cannot afford the costs of health services provided by public hospitals. On this background, and the old heritage of the Sudanese to help the needy, the Hawadith Street Initiative (HSI) was established. Named after the street on which it was founded - which translates indirectly to "Accidents Lane", HSI was established in 2012 by a group of youths, most of them in their twenties of age, and recently graduated. The main activity of the initiative is helping the needy hospital patients, especially with regards to their treatment costs, in Khartoum and other cities in Sudan. Starting with recreational programs for cancer patients, and public campaigns for donation of blood, the initiative's youths changed their activities. Using the social media, Facebook, they adopted the strategy of communication with potential donors, after sending posts containing brief anonymous presentations and call of help for needy cases. Currently HSI includes more than 2000 volunteers in Khartoum and 17 other cities. The most important achievement of HSI is the establishment of an intensive care unit at a children hospital in Omdurman city costing 435,880 US dollars. HSI demonstrates the possibility of delivering great services with minimum resources, and constitutes a unique organization, worldwide, in a new wave of Internet-based initiatives.

  11. Initial experience with robotic pancreatic surgery in Singapore: single institution experience with 30 consecutive cases.

    Science.gov (United States)

    Goh, Brian K P; Low, Tze-Yi; Lee, Ser-Yee; Chan, Chung-Yip; Chung, Alexander Y F; Ooi, London L P J

    2018-05-24

    Presently, the worldwide experience with robotic pancreatic surgery (RPS) is increasing although widespread adoption remains limited. In this study, we report our initial experience with RPS. This is a retrospective review of a single institution prospective database of 72 consecutive robotic hepatopancreatobiliary surgeries performed between 2013 and 2017. Of these, 30 patients who underwent RPS were included in this study of which 25 were performed by a single surgeon. The most common procedure was robotic distal pancreatectomy (RDP) which was performed in 20 patients. This included eight subtotal pancreatectomies, two extended pancreatecto-splenectomies (en bloc gastric resection) and 10 spleen-saving-RDP. Splenic preservation was successful in 10/11 attempted spleen-saving-RDP. Eight patients underwent pancreaticoduodenectomies (five hybrid with open reconstruction), one patient underwent a modified Puestow procedure and one enucleation of uncinate tumour. Four patients had extended resections including two RDP with gastric resection and two pancreaticoduodenectomies with vascular resection. There was one (3.3%) open conversion and seven (23.3%) major (>Grade II) morbidities. Overall, there were four (13.3%) clinically significant (Grade B) pancreatic fistulas of which three required percutaneous drainage. These occurred after three RDP and one robotic enucleation. There was one reoperation for port-site hernia and no 30-day/in-hospital mortalities. The median post-operative stay was 6.5 (range: 3-36) days and there were six (20%) 30-day readmissions. Our initial experience showed that RPS can be adopted safely with a low open conversion rate for a wide variety of procedures including pancreaticoduodenectomy. © 2018 Royal Australasian College of Surgeons.

  12. Performance of turbo high-pitch dual-source CT for coronary CT angiography: first ex vivo and patient experience

    Energy Technology Data Exchange (ETDEWEB)

    Morsbach, Fabian; Gordic, Sonja; Husarik, Daniela; Frauenfelder, Thomas; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); Desbiolles, Lotus; Leschka, Sebastian [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); Kantonsspital St. Gallen, Divison of Radiology and Nuclear Medicine, St. Gallen (Switzerland); Schmidt, Bernhard; Allmendinger, Thomas [Siemens AG, Healthcare Sector, Forchheim (Germany); Wildermuth, Simon [Kantonsspital St. Gallen, Divison of Radiology and Nuclear Medicine, St. Gallen (Switzerland)

    2014-08-15

    To evaluate image quality, maximal heart rate allowing for diagnostic imaging, and radiation dose of turbo high-pitch dual-source coronary computed tomographic angiography (CCTA). First, a cardiac motion phantom simulating heart rates (HRs) from 60-90 bpm in 5-bpm steps was examined on a third-generation dual-source 192-slice CT (prospective ECG-triggering, pitch 3.2; rotation time, 250 ms). Subjective image quality regarding the presence of motion artefacts was interpreted by two readers on a four-point scale (1, excellent; 4, non-diagnostic). Objective image quality was assessed by calculating distortion vectors. Thereafter, 20 consecutive patients (median, 50 years) undergoing clinically indicated CCTA were included. In the phantom study, image quality was rated diagnostic up to the HR75 bpm, with object distortion being 1 mm or less. Distortion increased above 1 mm at HR of 80-90 bpm. Patients had a mean HR of 66 bpm (47-78 bpm). Coronary segments were of diagnostic image quality for all patients with HR up to 73 bpm. Average effective radiation dose in patients was 0.6 ± 0.3 mSv. Our combined phantom and patient study indicates that CCTA with turbo high-pitch third-generation dual-source 192-slice CT can be performed at HR up to 75 bpm while maintaining diagnostic image quality, being associated with an average radiation dose of 0.6 mSv. (orig.)

  13. Performance of turbo high-pitch dual-source CT for coronary CT angiography: first ex vivo and patient experience

    International Nuclear Information System (INIS)

    Morsbach, Fabian; Gordic, Sonja; Husarik, Daniela; Frauenfelder, Thomas; Alkadhi, Hatem; Desbiolles, Lotus; Leschka, Sebastian; Schmidt, Bernhard; Allmendinger, Thomas; Wildermuth, Simon

    2014-01-01

    To evaluate image quality, maximal heart rate allowing for diagnostic imaging, and radiation dose of turbo high-pitch dual-source coronary computed tomographic angiography (CCTA). First, a cardiac motion phantom simulating heart rates (HRs) from 60-90 bpm in 5-bpm steps was examined on a third-generation dual-source 192-slice CT (prospective ECG-triggering, pitch 3.2; rotation time, 250 ms). Subjective image quality regarding the presence of motion artefacts was interpreted by two readers on a four-point scale (1, excellent; 4, non-diagnostic). Objective image quality was assessed by calculating distortion vectors. Thereafter, 20 consecutive patients (median, 50 years) undergoing clinically indicated CCTA were included. In the phantom study, image quality was rated diagnostic up to the HR75 bpm, with object distortion being 1 mm or less. Distortion increased above 1 mm at HR of 80-90 bpm. Patients had a mean HR of 66 bpm (47-78 bpm). Coronary segments were of diagnostic image quality for all patients with HR up to 73 bpm. Average effective radiation dose in patients was 0.6 ± 0.3 mSv. Our combined phantom and patient study indicates that CCTA with turbo high-pitch third-generation dual-source 192-slice CT can be performed at HR up to 75 bpm while maintaining diagnostic image quality, being associated with an average radiation dose of 0.6 mSv. (orig.)

  14. Coronary computed tomography angiography with 320-row detector and using the AIDR-3D: initial experience

    International Nuclear Information System (INIS)

    Sasdelli Neto, Roberto; Nomura, Cesar Higa; Macedo, Ana Carolina Sandoval; Bianco, Danilo Perussi; Kay, Fernando Uliana; Szarf, Gilberto; Teles, Gustavo Borges da Silva; Shoji, Hamilton; Santana Netto, Pedro Vieira; Passos, Rodrigo Bastos Duarte; Chate, Rodrigo Caruso; Ishikawa, Walther Yoshiharu; Lima, Joao Paulo Bacellar Costa; Rocha, Marcelo Assis; Marcos, Vinicius Neves; Funari, Marcelo Buarque de Gusmao; Failla, Bruna Bonaventura

    2013-01-01

    Coronary computed tomography angiography (coronary CTA) is a powerful non-invasive imaging method to evaluate coronary artery disease. Nowadays, coronary CTA estimated effective radiation dose can be dramatically reduced using state-of-the-art scanners, such as 320-row detector CT (320-CT), without changing coronary CTA diagnostic accuracy. To optimize and further reduce the radiation dose, new iterative reconstruction algorithms were released recently by several CT manufacturers, and now they are used routinely in coronary CTA. This paper presents our first experience using coronary CTA with 320-CT and the Adaptive Iterative Dose Reduction 3D (AIDR-3D). In addition, we describe the current indications for coronary CTA in our practice as well as the acquisition standard protocols and protocols related to CT application for radiation dose reduction. In conclusion, coronary CTA radiation dose can be dramatically reduced following the 'as low as reasonable achievable' principle by combination of exam indication and well-documented technics for radiation dose reduction, such as beta blockers, low-kV, and also the newest iterative dose reduction software as AIDR-3D. (author)

  15. Could new reconstruction CT techniques challenge MRI for the detection of brain metastases in the context of initial lung cancer staging?

    Energy Technology Data Exchange (ETDEWEB)

    Millon, Domitille; Byl, David; Coche, Emmanuel E. [Universite Catholique de Louvain, Department of Radiology and Medical Imaging, Cliniques Universitaires Saint Luc, Brussels (Belgium); Collard, Philippe [Universite Catholique de Louvain, Department of Pneumology, Cliniques Universitaires Saint Luc, Brussels (Belgium); Cambier, Samantha E.; Maanen, Aline G. van [Universite Catholique de Louvain, Statistic Unit, King Albert II Cancer Institute, Brussels (Belgium); Vlassenbroek, Alain [Philips Healthcare, Brussels (Belgium)

    2018-02-15

    To evaluate the diagnostic performance of brain CT images reconstructed with a model-based iterative algorithm performed at usual and reduced dose. 115 patients with histologically proven lung cancer were prospectively included over 15 months. Patients underwent two CT acquisitions at the initial staging, performed on a 256-slice MDCT, at standard (CTDIvol: 41.4 mGy) and half dose (CTDIvol: 20.7 mGy). Both image datasets were reconstructed with filtered back projection (FBP) and iterative model-based reconstruction (IMR) algorithms. Brain MRI was considered as the reference. Two blinded independent readers analysed the images. Ninety-three patients underwent all examinations. At the standard dose, eight patients presented 17 and 15 lesions on IMR and FBP CT images, respectively. At half-dose, seven patients presented 15 and 13 lesions on IMR and FBP CT images, respectively. The test could not highlight any significant difference between the standard dose IMR and the half-dose FBP techniques (p-value = 0.12). MRI showed 46 metastases on 11 patients. Specificity, negative and positive predictive values were calculated (98.9-100 %, 93.6-94.6 %, 75-100 %, respectively, for all CT techniques). No significant difference could be demonstrated between the two CT reconstruction techniques. (orig.)

  16. European Community initiatives and experience in scientific and technical information

    Energy Technology Data Exchange (ETDEWEB)

    Steven, G [Commission of the European Communities, Luxembourg (Luxembourg)

    1990-05-01

    Scientific and technical information (STI) is an increasingly important resource for R and D and industrial development. The rapid development of the market for electronic information and the increasing potential offered through new information technologies require new approaches for the collection and dissemination of STI. Activities of the Commission of the European Communities (CEC) in this area are reviewed. More recent CEC initiatives in the areas of biotechnology information and factual materials data banks have proved the need for international collaboration and for the implementation of infrastructural measures as a basis for such collaboration. The implementation of the EC Demonstrator Programme on materials property data systems has evaluated the potential of eleven European materials data banks against the market requirements and has helped to launch wide international collaboration. The concluding European workshop on materials data systems has developed a set of recommendations for future initiatives. These are shortly reviewed together with initial findings of a study aimed at developing a business plan for the establishment of a biotechnology information infrastructure for the bio-industries and research base in Europe. (author). 3 refs.

  17. European Community initiatives and experience in scientific and technical information

    International Nuclear Information System (INIS)

    Steven, G.

    1990-05-01

    Scientific and technical information (STI) is an increasingly important resource for R and D and industrial development. The rapid development of the market for electronic information and the increasing potential offered through new information technologies require new approaches for the collection and dissemination of STI. Activities of the Commission of the European Communities (CEC) in this area are reviewed. More recent CEC initiatives in the areas of biotechnology information and factual materials data banks have proved the need for international collaboration and for the implementation of infrastructural measures as a basis for such collaboration. The implementation of the EC Demonstrator Programme on materials property data systems has evaluated the potential of eleven European materials data banks against the market requirements and has helped to launch wide international collaboration. The concluding European workshop on materials data systems has developed a set of recommendations for future initiatives. These are shortly reviewed together with initial findings of a study aimed at developing a business plan for the establishment of a biotechnology information infrastructure for the bio-industries and research base in Europe. (author). 3 refs

  18. Formal reporting of second-opinion CT interpretation: experience and reimbursement in the emergency department setting.

    Science.gov (United States)

    Jeffers, Adam B; Saghir, Amina; Camacho, Marc

    2012-06-01

    The purpose of this study is to describe a system for formally reporting second-opinion interpretations of CT imaging exams accompanying patients transferred emergently to a tertiary care center. Second-opinion interpretations of cross-sectional imaging exams rendered in the emergency department setting over 6 months spanning 22 September 2009 to 22 March 2010 were reviewed and tallied by two radiologists and a research assistant, with a focus on professional fee reimbursement rates. A more in depth review was performed of those exams for which a clinical referral request form was available, detailing such information as the clinical history, content and source of available initial interpretation, and congruity of the initial interpretation with clinical data. Discrepancies between outside and second-opinion interpretations were also assessed. This quality assurance exercise was reviewed by our institutional review board, which waived formal informed consent. Formal second-opinion interpretation was rendered for 370 exams on 198 patients (mean age, 53.5 years; 45.1% female), received from 50 referring facilities. Head CT was the most common imaging exam referred for second opinion. Forty-one of 370 exams (11%) were submitted for self-pay, and 43 (12%) were written off as free care. The remaining 286 exams (77%) were submitted for reimbursement of the professional fee only. Ultimately, of the 286 exams submitted, 260 (91%) were reimbursed for professional fees, 199 (70%) on the initial submission. Of 29 health plans contracted with our facility, 22 ultimately approved all claims made. Three plans denied all claims submitted. The largest payer was Medicare, which reimbursed 88 of 90 submitted claims. Clinical intake forms were available for 184 exams on 107 patients (mean age, 52.7 years, 43.0% female). Trauma was the most common indication, or history, provided (55% of 184 exams, 40% of 107 patients). An outside report of some form was available for 112 of the 184

  19. Impact of institutional volume and experience with CT interpretation on sizing of transcatheter aortic valves: A multicenter retrospective study

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Divya Ratan [Cardiovascular Institute, Banner University Medical Center, Phoenix, AZ (United States); Division of Interventional Cardiology, Banner University Medical Center, Phoenix, AZ (United States); Pershad, Yash [Department of Radiology, Banner University Medical Center, Phoenix, AZ (United States); Pershad, Ashish [Cardiovascular Institute, Banner University Medical Center, Phoenix, AZ (United States); Division of Interventional Cardiology, Banner University Medical Center, Phoenix, AZ (United States); Fang, Kenith [Cardiovascular Institute, Banner University Medical Center, Phoenix, AZ (United States); Division of Cardiothoracic Surgery, Banner University Medical Center, Phoenix, AZ (United States); Gellert, George [Cardiovascular Institute, Banner University Medical Center, Phoenix, AZ (United States); Department of Anesthesiology, Banner University Medical Center, Phoenix, AZ (United States); Morris, Michael F., E-mail: mfmorris@mail.arizona.edu [Cardiovascular Institute, Banner University Medical Center, Phoenix, AZ (United States); Department of Radiology, Banner University Medical Center, Phoenix, AZ (United States)

    2016-12-15

    Background: Computed tomography (CT) has become the standard imaging modality for pre-procedural aortic annular sizing prior to transcatheter aortic valve replacement (TAVR). We hypothesized that the accuracy of CT derived annular measurements would be greater at sites with higher TAVR procedural volume. Methods: Within a large integrated health system, TAVR was performed at low (<40 cases), intermediate (40–75 cases), and high-volume sites (>75 cases). 181 patients underwent TAVR with a Sapien XT transcatheter heart valve (THV). Two blinded experienced readers independently remeasured the annulus on CT and compared their measurements to site reported measurements. Hypothetical THV sizes were chosen based on measurements from site CT reports and independent readers’ measurements, and compared to the implanted THV size. Results: Correlation between site reported measurements and independent readers measurements of mean annulus size varied between low-volume (r = 0.31, p = 0.18), intermediate-volume (r = 0.34, p = 0.01), and high-volume sites (r = 0.96, p < 0.01). On multivariate analysis, interpretation of ≥20 CT scans (OR 0.29; 95% CI 0.03–0.81; p 0.02) and high-volume site (OR 0.16; 95% CI 0.10–0.82; p 0.02) were associated with reduced mismatch between the site predicted THV size and independent readers predicted THV size. Mismatch between site predicted THV size and implanted THV size was associated with a worse 30-day composite of mortality, dialysis-dependent renal failure, cerebrovascular accident, new permanent pacemaker, and hospital readmission (55.3 vs. 38.7%; p = 0.05). Conclusions: Accuracy of CT aortic annular sizing is improved with higher individual experience and site TAVR volume. These findings should be confirmed in larger, prospective studies. - Highlights: • Accuracy of CT aortic annular sizing is improved with higher individual experience and site TAVR volume. • CT readers with experience interpreting ≥20 pre-TAVR CT scans had

  20. Impact of institutional volume and experience with CT interpretation on sizing of transcatheter aortic valves: A multicenter retrospective study

    International Nuclear Information System (INIS)

    Verma, Divya Ratan; Pershad, Yash; Pershad, Ashish; Fang, Kenith; Gellert, George; Morris, Michael F.

    2016-01-01

    Background: Computed tomography (CT) has become the standard imaging modality for pre-procedural aortic annular sizing prior to transcatheter aortic valve replacement (TAVR). We hypothesized that the accuracy of CT derived annular measurements would be greater at sites with higher TAVR procedural volume. Methods: Within a large integrated health system, TAVR was performed at low ( 75 cases). 181 patients underwent TAVR with a Sapien XT transcatheter heart valve (THV). Two blinded experienced readers independently remeasured the annulus on CT and compared their measurements to site reported measurements. Hypothetical THV sizes were chosen based on measurements from site CT reports and independent readers’ measurements, and compared to the implanted THV size. Results: Correlation between site reported measurements and independent readers measurements of mean annulus size varied between low-volume (r = 0.31, p = 0.18), intermediate-volume (r = 0.34, p = 0.01), and high-volume sites (r = 0.96, p < 0.01). On multivariate analysis, interpretation of ≥20 CT scans (OR 0.29; 95% CI 0.03–0.81; p 0.02) and high-volume site (OR 0.16; 95% CI 0.10–0.82; p 0.02) were associated with reduced mismatch between the site predicted THV size and independent readers predicted THV size. Mismatch between site predicted THV size and implanted THV size was associated with a worse 30-day composite of mortality, dialysis-dependent renal failure, cerebrovascular accident, new permanent pacemaker, and hospital readmission (55.3 vs. 38.7%; p = 0.05). Conclusions: Accuracy of CT aortic annular sizing is improved with higher individual experience and site TAVR volume. These findings should be confirmed in larger, prospective studies. - Highlights: • Accuracy of CT aortic annular sizing is improved with higher individual experience and site TAVR volume. • CT readers with experience interpreting ≥20 pre-TAVR CT scans had significantly improved accuracy in identifying the annulus.

  1. Young Asian Women Experiences of the Summer Activities Initiative.

    Science.gov (United States)

    Kirby, Laura

    2002-01-01

    Interviews and observations focused on experiences of 15 young Asian women at a 5-day summer adventure program in southern England. Participants seemed bored with presentations about future career options, activities lost their challenge through repetition, and debriefing was weak. However, the women connected with the transferable skills of trust…

  2. MDCT of acute pancreatitis: Intraindividual comparison of single-phase versus dual-phase MDCT for initial assessment of acute pancreatitis using different CT scoring systems

    Energy Technology Data Exchange (ETDEWEB)

    Avanesov, Maxim, E-mail: m.avanesov@uke.de [Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg (Germany); Weinrich, Julius M.; Kraus, Thomas [Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg (Germany); Derlin, Thorsten [Department of Nuclear Medicine, Hannover Medical School (Germany); Adam, Gerhard; Yamamura, Jin [Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg (Germany); Karul, Murat [Department of Diagnostic and Interventional Radiology, Marienkrankenhaus Hamburg (Germany)

    2016-11-15

    Objectives: The purpose of the retrospective study was to evaluate the additional value of dual-phase multidetector computed tomography (MDCT) protocols over a single-phase protocol on initial MDCT in patients with acute pancreatitis using three CT-based pancreatitis severity scores with regard to radiation dose. Methods: In this retrospective, IRB approved study MDCT was performed in 102 consecutive patients (73 males; 55years, IQR48–64) with acute pancreatitis. Inclusion criteria were CT findings of interstitial edematous pancreatitis (IP) or necrotizing pancreatitis (NP) and a contrast-enhanced dual-phase (arterial phase and portal-venous phase) abdominal CT performed at ≥72 h after onset of symptoms. The severity of pancreatic and extrapancreatic changes was independently assessed by 2 observers using 3 validated CT-based scoring systems (CTSI, mCTSI, EPIC). All scores were applied to arterial phase and portal venous phase scans and compared to score results of portal venous phase scans, assessed ≥14 days after initial evaluation. For effective dose estimation, volume CT dose index (CTDIvol) and dose length product (DLP) were recorded in all examinations. Results: In neither of the CT severity scores a significant difference was observed after application of a dual-phase protocol compared with a single-phase protocol (IP: CTSI: 2.7 vs. 2.5, p = 0.25; mCTSI: 4.0 vs. 4.0, p = 0.10; EPIC: 2.0 vs. 2.0, p = 0.41; NP: CTSI: 8.0 vs. 7.0, p = 0.64; mCTSI: 8.0 vs. 8.0, p = 0.10; EPIC: 3.0 vs. 3.0, p = 0.06). The application of a single-phase CT protocol was associated with a median effective dose reduction of 36% (mean dose reduction 31%) compared to a dual-phase CT scan. Conclusions: An initial dual-phase abdominal CT after ≥72 h after onset of symptoms of acute pancreatitis was not superior to a single-phase protocol for evaluation of the severity of pancreatic and extrapancreatic changes. However, the effective radiation dose may be reduced by 36% using a

  3. Impact of initial FDG-PET/CT and serum-free light chain on transformation of conventionally defined solitary plasmacytoma to multiple myeloma.

    Science.gov (United States)

    Fouquet, Guillemette; Guidez, Stéphanie; Herbaux, Charles; Van de Wyngaert, Zoé; Bonnet, Sarah; Beauvais, David; Demarquette, Hélène; Adib, Salim; Hivert, Bénédicte; Wemeau, Mathieu; Berthon, Céline; Terriou, Louis; Coiteux, Valérie; Macro, Margaret; Decaux, Olivier; Facon, Thierry; Huglo, Damien; Leleu, Xavier

    2014-06-15

    Solitary plasmacytoma (SP) is a localized proliferation of monoclonal plasma cells in either bone or soft tissue, without evidence of multiple myeloma (MM), and whose prognosis is marked by a high risk of transformation to MM. We studied the impact of FDG-PET/CT (2[18F]fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography) on the risk of transformation of SP to overt MM among other markers in a series of 43 patients diagnosed with SP. Median age was 57.5 years; 48% of patients had an abnormal involved serum-free light chain (sFLC) value, and 64% had an abnormal sFLC ratio at diagnosis. Thirty-three percent had two or more hypermetabolic lesions on initial PET/CT, and 20% had two or more focal lesions on initial MRI. With a median follow-up of 50 months, 14 patients transformed to MM with a median time (TTMM) of 71 months. The risk factors that significantly shortened TTMM at diagnosis were two or more hypermetabolic lesions on PET/CT, abnormal sFLC ratio and involved sFLC, and to a lesser extent at completion of treatment, absence of normalized involved sFLC and PET/CT or MRI. In a multivariate analysis, abnormal initial involved sFLC [OR = 10; 95% confidence interval (CI), 1-87; P = 0.008] and PET/CT (OR = 5; 95% CI, 0-9; P = 0.032) independently shortened TTMM. An abnormal involved sFLC value and the presence of at least two hypermetabolic lesions on PET/CT at diagnosis of SP were the two predictors of early evolution to myeloma in our series. This data analysis will need confirmation in a larger study, and the study of these two risk factors may lead to a different management of patients with SP in the future. . ©2014 American Association for Cancer Research.

  4. An Initial Approach for Learning Objects from Experience

    Science.gov (United States)

    2018-05-02

    algorithm to delineate objects which are then fed to a simple feed-forward neural network without any other processes in the pipeline. Our neural network...These are the basic requirements for the pipeline and are discussed in more detail below. Additionally, we are interested in testing various parts...that continuously learning objects from experience requires mechanisms to do the following: 1) Focus attention on things and stuff of interest . 2

  5. Negative Interest Rates: Central Banks Initiated an Experiment

    OpenAIRE

    Aleksey N. Burenin

    2016-01-01

    Negative interest rates appeared as a consequence of economic problems that countries with market economy came across after the crises of2007-2008. The attempts of monetary authorities to stimulate economies with the help of quantitative easing didn't bring the desired result. That's why the central banks once again resorted to a traditional tool of their monetary policy of changing interest rates. But this time they launched an experiment, they used negative interest rates. The European Cent...

  6. Cardiac biplane strain imaging: initial in vivo experience

    Science.gov (United States)

    Lopata, R. G. P.; Nillesen, M. M.; Verrijp, C. N.; Singh, S. K.; Lammens, M. M. Y.; van der Laak, J. A. W. M.; van Wetten, H. B.; Thijssen, J. M.; Kapusta, L.; de Korte, C. L.

    2010-02-01

    In this study, first we propose a biplane strain imaging method using a commercial ultrasound system, yielding estimation of the strain in three orthogonal directions. Secondly, an animal model of a child's heart was introduced that is suitable to simulate congenital heart disease and was used to test the method in vivo. The proposed approach can serve as a framework to monitor the development of cardiac hypertrophy and fibrosis. A 2D strain estimation technique using radio frequency (RF) ultrasound data was applied. Biplane image acquisition was performed at a relatively low frame rate (dogs with an aortic stenosis. Initial results reveal the feasibility of measuring large radial, circumferential and longitudinal cumulative strain (up to 70%) at a frame rate of 100 Hz. Mean radial strain curves of a manually segmented region-of-interest in the infero-lateral wall show excellent correlation between the measured strain curves acquired in two perpendicular planes. Furthermore, the results show the feasibility and reproducibility of assessing radial, circumferential and longitudinal strains simultaneously. In this preliminary study, three beagles developed an elevated pressure gradient over the aortic valve (Δp: 100-200 mmHg) and myocardial hypertrophy. One dog did not develop any sign of hypertrophy (Δp = 20 mmHg). Initial strain (rate) results showed that the maximum strain (rate) decreased with increasing valvular stenosis (-50%), which is in accordance with previous studies. Histological findings corroborated these results and showed an increase in fibrotic tissue for the hearts with larger pressure gradients (100, 200 mmHg), as well as lower strain and strain rate values.

  7. Cardiac biplane strain imaging: initial in vivo experience

    Energy Technology Data Exchange (ETDEWEB)

    Lopata, R G P; Nillesen, M M; Thijssen, J M; De Korte, C L [Clinical Physics Laboratory, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Verrijp, C N; Lammens, M M Y; Van der Laak, J A W M [Department of Pathology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Singh, S K; Van Wetten, H B [Department of Cardiothoracic Surgery, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Kapusta, L [Pediatric Cardiology, Department of Pediatrics, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)], E-mail: R.Lopata@cukz.umcn.nl

    2010-02-21

    In this study, first we propose a biplane strain imaging method using a commercial ultrasound system, yielding estimation of the strain in three orthogonal directions. Secondly, an animal model of a child's heart was introduced that is suitable to simulate congenital heart disease and was used to test the method in vivo. The proposed approach can serve as a framework to monitor the development of cardiac hypertrophy and fibrosis. A 2D strain estimation technique using radio frequency (RF) ultrasound data was applied. Biplane image acquisition was performed at a relatively low frame rate (<100 Hz) using a commercial platform with an RF interface. For testing the method in vivo, biplane image sequences of the heart were recorded during the cardiac cycle in four dogs with an aortic stenosis. Initial results reveal the feasibility of measuring large radial, circumferential and longitudinal cumulative strain (up to 70%) at a frame rate of 100 Hz. Mean radial strain curves of a manually segmented region-of-interest in the infero-lateral wall show excellent correlation between the measured strain curves acquired in two perpendicular planes. Furthermore, the results show the feasibility and reproducibility of assessing radial, circumferential and longitudinal strains simultaneously. In this preliminary study, three beagles developed an elevated pressure gradient over the aortic valve ({delta}p: 100-200 mmHg) and myocardial hypertrophy. One dog did not develop any sign of hypertrophy ({delta}p = 20 mmHg). Initial strain (rate) results showed that the maximum strain (rate) decreased with increasing valvular stenosis (-50%), which is in accordance with previous studies. Histological findings corroborated these results and showed an increase in fibrotic tissue for the hearts with larger pressure gradients (100, 200 mmHg), as well as lower strain and strain rate values.

  8. Cardiac biplane strain imaging: initial in vivo experience

    International Nuclear Information System (INIS)

    Lopata, R G P; Nillesen, M M; Thijssen, J M; De Korte, C L; Verrijp, C N; Lammens, M M Y; Van der Laak, J A W M; Singh, S K; Van Wetten, H B; Kapusta, L

    2010-01-01

    In this study, first we propose a biplane strain imaging method using a commercial ultrasound system, yielding estimation of the strain in three orthogonal directions. Secondly, an animal model of a child's heart was introduced that is suitable to simulate congenital heart disease and was used to test the method in vivo. The proposed approach can serve as a framework to monitor the development of cardiac hypertrophy and fibrosis. A 2D strain estimation technique using radio frequency (RF) ultrasound data was applied. Biplane image acquisition was performed at a relatively low frame rate (<100 Hz) using a commercial platform with an RF interface. For testing the method in vivo, biplane image sequences of the heart were recorded during the cardiac cycle in four dogs with an aortic stenosis. Initial results reveal the feasibility of measuring large radial, circumferential and longitudinal cumulative strain (up to 70%) at a frame rate of 100 Hz. Mean radial strain curves of a manually segmented region-of-interest in the infero-lateral wall show excellent correlation between the measured strain curves acquired in two perpendicular planes. Furthermore, the results show the feasibility and reproducibility of assessing radial, circumferential and longitudinal strains simultaneously. In this preliminary study, three beagles developed an elevated pressure gradient over the aortic valve (Δp: 100-200 mmHg) and myocardial hypertrophy. One dog did not develop any sign of hypertrophy (Δp = 20 mmHg). Initial strain (rate) results showed that the maximum strain (rate) decreased with increasing valvular stenosis (-50%), which is in accordance with previous studies. Histological findings corroborated these results and showed an increase in fibrotic tissue for the hearts with larger pressure gradients (100, 200 mmHg), as well as lower strain and strain rate values.

  9. Management support to e-business initiatives: The Croatian experience

    Directory of Open Access Journals (Sweden)

    Mario Spremić

    2003-01-01

    Full Text Available After defining e-business and explaining why an evolutionary aspect of moving to e-business is required, the dimensions of e-business is defined with respect to differences between traditional business, partial, or pure e-business. Also, a model for moving to e-business is illustrated. The e-business evolving model is divided into six stages and represents an evolutionary aspect of migrating to e-business. Finally, the results of the research study on current practices in evolving e-business in the most successful Croatian companies are given. In this research, some aspects of business process innovation and e-business usage have been investigated (general e-business issues with levels of e-business usage, key objectives of participating in e-business, alignment of business strategy with e-business initiatives, initiation of e-business projects and e-business planning issues, especially e-business funding. The questionnaire was sent to 400 CEOs or CIOs in Croatian companies selected from the Register of the ‘400 Biggest’ Croatian companies which were ranked according to their 2001 annual revenue and which were most likely to represent the structure of the Croatian economy. Although they represent less than 1% of the total number of registered companies in Croatia, the sampled companies hold 73% of the equity capital of the whole Croatian economy, they contribute with 65% in the total Croatian economy’s export balance and they employ 37% of the total number of people employed in Croatia.

  10. Dual-contrast agent photon-counting computed tomography of the heart: initial experience.

    Science.gov (United States)

    Symons, Rolf; Cork, Tyler E; Lakshmanan, Manu N; Evers, Robert; Davies-Venn, Cynthia; Rice, Kelly A; Thomas, Marvin L; Liu, Chia-Ying; Kappler, Steffen; Ulzheimer, Stefan; Sandfort, Veit; Bluemke, David A; Pourmorteza, Amir

    2017-08-01

    To determine the feasibility of dual-contrast agent imaging of the heart using photon-counting detector (PCD) computed tomography (CT) to simultaneously assess both first-pass and late enhancement of the myocardium. An occlusion-reperfusion canine model of myocardial infarction was used. Gadolinium-based contrast was injected 10 min prior to PCD CT. Iodinated contrast was infused immediately prior to PCD CT, thus capturing late gadolinium enhancement as well as first-pass iodine enhancement. Gadolinium and iodine maps were calculated using a linear material decomposition technique and compared to single-energy (conventional) images. PCD images were compared to in vivo and ex vivo magnetic resonance imaging (MRI) and histology. For infarct versus remote myocardium, contrast-to-noise ratio (CNR) was maximal on late enhancement gadolinium maps (CNR 9.0 ± 0.8, 6.6 ± 0.7, and 0.4 ± 0.4, p contrast agent cardiac imaging is feasible with photon-counting detector CT. These initial proof-of-concept results may provide incentives to develop new k-edge contrast agents, to investigate possible interactions between multiple simultaneously administered contrast agents, and to ultimately bring them to clinical practice.

  11. The Planeterrella experiment: from individual initiative to networking

    Directory of Open Access Journals (Sweden)

    Garnier Pierre

    2013-02-01

    Full Text Available Space weather is a relatively new discipline, which is still largely unknown amongst the wider public despite its increasing importance in all of our daily lives. Outreach activities can promote awareness of space weather. In particular the visual beauty and excitement of the aurora make these lights a wonderful inspirational hook to enhance understanding of space weather in a general audience. A century ago, the Norwegian experimental physicist Kristian Birkeland, one of the founding fathers of modern space science, demonstrated with his Terrella experiment the formation of the aurora. Recently, a modernized version of the Terrella has been designed. This “Planeterrella” experiment allows the visualization of many phenomena that occur in our space environment. Although the Planeterrella was originally a local project, it has developed to become a very successful international public outreach experiment. We believe that its success is due to mainly two factors (i the Planeterrella is not patented and the plans are free to any public institute and (ii the project is widely advertised using national and European scientific networks such as COST ES 0803, as well as press releases, books and web sites. Today, seven Planeterrellas are in operation, four more are under construction in four different countries and several more are being planned. During the last five years, about 50 000 people in Europe have attended live Planeterrella demonstration on the formation of auroral light, the space environment and space weather. Many more have seen the Planeterrella being demonstrated on TV. The Planeterrella received the first international prize for outreach activities from the Europlanet Framework 7 program in 2010 and the French Ministry of Science outreach prize “Le goût des sciences” in November 2012. This paper describes the process that led to the construction of the first Planeterrella and discusses how the Planeterrella project developed

  12. The Planeterrella experiment: from individual initiative to networking

    Science.gov (United States)

    Lilensten, J.; Provan, G.; Barthelemy, M.; Simon Wedlund, C.; Gronoff, G.; Vanlommel, P.; Brekke, A.; Garnier, P.; Grimald Rochel, S.

    2013-12-01

    Space weather is a relatively new discipline, which is still largely unknown amongst the wider public despite its increasing importance in all of our daily lives. Outreach activities can promote awareness of space weather. In particular the visual beauty and excitement of the aurora make these lights a wonderful inspirational hook to enhance understanding of space weather in a general audience. A century ago, the Norwegian experimental physicist Kristian Birkeland, one of the founding fathers of modern space science, demonstrated with his Terrella experiment the formation of the aurora. Recently, a modernized version of the Terrella has been designed in France. This ';';Planeterrella'' experiment allows the visualization of many phenomena that occur in our space environment. Although the Planeterrella was originally a local project, it has developed to become a very successful international public outreach experiment. We believe that its success is due to mainly two factors (i) the Planeterrella is not patented and the plans are free to any public institute and (ii) the project is widely advertised using national and scientific networks, as well as press releases, books and web sites. Today, nine Planeterrellas are in operation, six more are under construction in five different countries including in the US and several more are being planned. During the last five years, about 55 000 people in Europe have attended live Planeterrella demonstration on the formation of auroral light, the space environment and space weather. Many more have seen the Planeterrella being demonstrated on TV. It is now used for education, outreach, scientific, and artistic purposes. We will describes this process and discuss how the Planeterrella project developed to become an international public outreach phenomenon. We also examine some of the lessons learnt along the way such as patented or not, big or small, automatized or hand-operated, and the cost of the overall project. A star (close

  13. Paediatric magnetic resonance enteroclysis under general anaesthesia - initial experience

    International Nuclear Information System (INIS)

    Sadigh, Sophie; Chopra, Mark; Olsen, Oeystein E.; Watson, Tom A.; Sury, Michael R.; Shah, Neil

    2017-01-01

    MR enterography is the accepted imaging reference standard for small bowel assessment in inflammatory bowel disease. There is an increasing cohort of children with inflammatory bowel disease presenting at an early age (<5 years) with severe disease. Younger children present a technical challenge for enterography because of the need for sedation/general anaesthesia to allow image optimisation and the need for oral contrast to allow adequate luminal assessment. Through our experiences, MR enteroclysis under general anaesthesia has proven to be a successful imaging technique for the work-up of these patients. In this paper, we present our institutional practice for performing MR enteroclysis under general anaesthesia. (orig.)

  14. Paediatric magnetic resonance enteroclysis under general anaesthesia - initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Sadigh, Sophie; Chopra, Mark; Olsen, Oeystein E.; Watson, Tom A. [Great Ormond Street Hospital NHS Foundation Trust, Department of Paediatric Radiology, London (United Kingdom); Sury, Michael R. [Great Ormond Street Hospital NHS Foundation Trust, Department of Paediatric Anaesthetics, London (United Kingdom); Shah, Neil [Great Ormond Street Hospital NHS Foundation Trust, Department of Paediatric Gastroenterology, London (United Kingdom)

    2017-06-15

    MR enterography is the accepted imaging reference standard for small bowel assessment in inflammatory bowel disease. There is an increasing cohort of children with inflammatory bowel disease presenting at an early age (<5 years) with severe disease. Younger children present a technical challenge for enterography because of the need for sedation/general anaesthesia to allow image optimisation and the need for oral contrast to allow adequate luminal assessment. Through our experiences, MR enteroclysis under general anaesthesia has proven to be a successful imaging technique for the work-up of these patients. In this paper, we present our institutional practice for performing MR enteroclysis under general anaesthesia. (orig.)

  15. Complications in paediatric craniofacial surgery: an initial four year experience.

    Science.gov (United States)

    Jones, B M; Jani, P; Bingham, R M; Mackersie, A M; Hayward, R

    1992-04-01

    107 children undergoing transcranial craniofacial surgery in a paediatric hospital have been reviewed to assess the incidence and type of complications which arose. This represents the first 4 years' experience of the craniofacial team. There were no deaths or permanent adverse sequelae of surgery. A total of 53 complications were seen in 42 patients. In 9.3% of patients they were potentially life-threatening, serious in 12.1% and of a minor nature in 28%. The more serious complications were related either to haemorrhage and/or vasovagal shock at operation or to infection post-operatively. Infants undergoing monoblock frontofacial advancements and those with tracheostomies were at particular risk.

  16. Overnight Emergency CT Imaging: A 10-Year Experience at an Irish Tertiary Referral Hospital.

    LENUS (Irish Health Repository)

    2018-01-01

    In recent years there has been increased utilisation of computed tomography (CT) imaging in developed countries, however there is a paucity of data regarding the utilisation of CT in the emergency overnight setting. We retrospectively analysed trends in ‘overnight’ (midnight to 8am) CT utilisation over a ten-year period at a single Irish tertiary referral hospital. Over the study period, we observed a significant increase in the proportion of CT imaging that was carried out overnight. There was no significant variation in the yield of pathological findings over the study period, which remained low (64% of CT studies were normal or had non-critical findings). The multiple factors which have contributed to the increased utilization of overnight emergency CT in recent years, the potential for reporting errors overnight and the implications therein for patient safety warrant consideration.

  17. Commissioning and initial experience with the ALICE on-line

    International Nuclear Information System (INIS)

    Altini, V; Anticic, T; Carena, F; Carena, W; Chapeland, S; Barroso, V Chibante; Costa, F; Divia, R; Fuchs, U; Makhlyueva, I; Roukoutakis, F; Schossmaier, K; Soos, C; Vyvre, P Vande; Haller, B von; Denes, E; Kiss, T

    2010-01-01

    ALICE (A Large Ion Collider Experiment) is the heavy-ion detector designed to study the physics of strongly interacting matter and the quark-gluon plasma at the CERN Large Hadron Collider (LHC). A large bandwidth and flexible Data Acquisition System (DAQ) has been designed and deployed to collect sufficient statistics in the short running time available per year for heavy ions and to accommodate very different requirements originated from the 18 sub-detectors. This paper will present the large scale tests conducted to assess the standalone DAQ performances, the interfaces with the other online systems and the extensive commissioning performed in order to be fully prepared for physics data taking. It will review the experience accumulated since May 2007 during the standalone commissioning of the main detectors and the global cosmic runs and the lessons learned from this exposure on the b attle field . It will also discuss the test protocol followed to integrate and validate each sub-detector with the online systems and it will conclude with the first results of the LHC injection tests and startup in September 2008. Several papers of the same conference present in more details some elements of the ALICE DAQ system.

  18. Commissioning and initial experience with the ALICE on-line

    Energy Technology Data Exchange (ETDEWEB)

    Altini, V [INFN, Dipartimento di Fisica dell' Universita and Sezione INFN Bari (Italy); Anticic, T [Ruder Botkovic Institute, Zagreb (Croatia); Carena, F; Carena, W; Chapeland, S; Barroso, V Chibante; Costa, F; Divia, R; Fuchs, U; Makhlyueva, I; Roukoutakis, F; Schossmaier, K; Soos, C; Vyvre, P Vande; Haller, B von [CERN, Physics department, Geneva (Switzerland); Denes, E; Kiss, T, E-mail: pierre.vande.vyvre@cern.c [KFKI Research Institute for Particle and Nuclear Physics, Budapest (Hungary)

    2010-04-01

    ALICE (A Large Ion Collider Experiment) is the heavy-ion detector designed to study the physics of strongly interacting matter and the quark-gluon plasma at the CERN Large Hadron Collider (LHC). A large bandwidth and flexible Data Acquisition System (DAQ) has been designed and deployed to collect sufficient statistics in the short running time available per year for heavy ions and to accommodate very different requirements originated from the 18 sub-detectors. This paper will present the large scale tests conducted to assess the standalone DAQ performances, the interfaces with the other online systems and the extensive commissioning performed in order to be fully prepared for physics data taking. It will review the experience accumulated since May 2007 during the standalone commissioning of the main detectors and the global cosmic runs and the lessons learned from this exposure on the {sup b}attle field{sup .} It will also discuss the test protocol followed to integrate and validate each sub-detector with the online systems and it will conclude with the first results of the LHC injection tests and startup in September 2008. Several papers of the same conference present in more details some elements of the ALICE DAQ system.

  19. Commissioning and initial experience with the ALICE on-line

    Science.gov (United States)

    Altini, V.; Anticic, T.; Carena, F.; Carena, W.; Chapeland, S.; Chibante Barroso, V.; Costa, F.; Dénes, E.; Divià, R.; Fuchs, U.; Kiss, T.; Makhlyueva, I.; Roukoutakis, F.; Schossmaier, K.; Soós, C.; Vande Vyvre, P.; von Haller, B.; ALICE Collaboration

    2010-04-01

    ALICE (A Large Ion Collider Experiment) is the heavy-ion detector designed to study the physics of strongly interacting matter and the quark-gluon plasma at the CERN Large Hadron Collider (LHC). A large bandwidth and flexible Data Acquisition System (DAQ) has been designed and deployed to collect sufficient statistics in the short running time available per year for heavy ions and to accommodate very different requirements originated from the 18 sub-detectors. This paper will present the large scale tests conducted to assess the standalone DAQ performances, the interfaces with the other online systems and the extensive commissioning performed in order to be fully prepared for physics data taking. It will review the experience accumulated since May 2007 during the standalone commissioning of the main detectors and the global cosmic runs and the lessons learned from this exposure on the "battle field". It will also discuss the test protocol followed to integrate and validate each sub-detector with the online systems and it will conclude with the first results of the LHC injection tests and startup in September 2008. Several papers of the same conference present in more details some elements of the ALICE DAQ system.

  20. Initial experience with purely laparoscopic living-donor right hepatectomy.

    Science.gov (United States)

    Hong, S K; Lee, K W; Choi, Y; Kim, H S; Ahn, S W; Yoon, K C; Kim, H; Yi, N J; Suh, K S

    2018-05-01

    There may be concerns about purely laparoscopic donor right hepatectomy (PLDRH) compared with open donor right hepatectomy, especially when performed by surgeons accustomed to open surgery. This study aimed to describe technical tips and pitfalls in PLDRH. Data from donors who underwent PLDRH at Seoul National University Hospital between December 2015 and July 2017 were analysed retrospectively. Endpoints analysed included intraoperative events and postoperative complications. All operations were performed by a single surgeon with considerable experience in open living donor hepatectomy. A total of 26 donors underwent purely laparoscopic right hepatectomy in the study interval. No donor required transfusion during surgery, whereas two underwent reoperation. In two donors, the dissection plane at the right upper deep portion of the midplane was not correct. One donor experienced portal vein injury during caudate lobe transection, and one developed remnant left hepatic duct stenosis. One donor experienced remnant portal vein angulation owing to a different approach angle, and one experienced arterial damage associated with the use of a laparoscopic energy device. One donor had postoperative bleeding due to masking of potential bleeding foci owing to intra-abdominal pressure during laparoscopy. Two donors experienced right liver surface damage caused by a xiphoid trocar. Purely laparoscopic donor hepatectomy differs from open donor hepatectomy in terms of angle and caudal view. Therefore, surgeons experienced in open donor hepatectomy must gain adequate experience in laparoscopic liver surgery and make adjustments when performing PLDRH. © 2018 BJS Society Ltd Published by John Wiley & Sons Ltd.

  1. Robotic-assisted partial Nephrectomy: initial experience in South America

    Directory of Open Access Journals (Sweden)

    Gustavo C. Lemos

    2011-08-01

    Full Text Available OBJECTIVE:To report the initial outcomes of robotic-assisted partial nephrectomy in a tertiary center in South America. MATERIAL AND METHODS: From 11/2008 to 12/2009, a total of 16 transperitoneal robotic-assisted partial nephrectomies were performed in 15 patients to treat 18 kidney tumors. One patient with bilateral tumor had two procedures, while two patients with two synchronous unilateral tumors had a single operation to remove them. Eleven (73% patients were male and the right kidney was affected in 7 (46% patients. The median patient age and tumor size were 57 years old and 30 mm, respectively. Five (28% tumors were hilar and/or centrally located. RESULTS: The median operative time, warm ischemia time and estimated blood loss was 140 min, 27 min and 120 mL, respectively. Blood transfusion was required in one patient with bilateral tumor, and one additional pyelolithotomy was performed due to a 15mm stone located in the renal pelvis. The histopathology analysis showed 15 (83% malignant tumors, which 10 (67% were clear cell carcinoma. The median hospital stay was 72 hrs and no major complication was observed. CONCLUSION: Robotic-assisted partial nephrectomy is safe and represents a valuable option to perform minimally invasive nephron-sparing surgery.

  2. Robotic-assisted laparoscopic partial nephrectomy: initial experience in Brazil and a review of the literature

    Directory of Open Access Journals (Sweden)

    Carlo Camargo Passerotti

    2012-02-01

    Full Text Available CONTEXT AND PURPOSE: Partial nephrectomy has become the standard of care for renal tumors less than 4 cm in diameter. Controversy still exists, however, regarding the best surgical approach, especially when minimally invasive techniques are taken into account. Robotic-assisted laparoscopic partial nephrectomy (RALPN has emerged as a promising technique that helps surgeons achieve the standards of open partial nephrectomy care while offering a minimally invasive approach. The objective of the present study was to describe our initial experience with robotic-assisted laparoscopic partial nephrectomy and extensively review the pertinent literature. MATERIALS AND METHODS: Between August 2009 and February 2010, eight consecutive selected patients with contrast enhancing renal masses observed by CT were submitted to RALPN in a private institution. In addition, we collected information on the patients' demographics, preoperative tumor characteristics and detailed operative, postoperative and pathological data. In addition, a PubMed search was performed to provide an extensive review of the robotic-assisted laparoscopic partial nephrectomy literature. RESULTS: Seven patients had RALPN on the left or right sides with no intraoperative complications. One patient was electively converted to a robotic-assisted radical nephrectomy. The operative time ranged from 120 to 300 min, estimated blood loss (EBL ranged from 75 to 400 mL and, in five cases, the warm ischemia time (WIT ranged from 18 to 32 min. Two patients did not require any clamping. Overall, no transfusions were necessary, and there were no intraoperative complications or adverse postoperative clinical events. All margins were negative, and all patients were disease-free at the 6-month follow-up. CONCLUSIONS: Robotic-assisted laparoscopic partial nephrectomy is a feasible and safe approach to small renal cortical masses.Further prospective studies are needed to compare open partial nephrectomy with

  3. Augmented Reality Guidance for the Resection of Missing Colorectal Liver Metastases: An Initial Experience.

    Science.gov (United States)

    Ntourakis, Dimitrios; Memeo, Ricardo; Soler, Luc; Marescaux, Jacques; Mutter, Didier; Pessaux, Patrick

    2016-02-01

    Modern chemotherapy achieves the shrinking of colorectal cancer liver metastases (CRLM) to such extent that they may disappear from radiological imaging. Disappearing CRLM rarely represents a complete pathological remission and have an important risk of recurrence. Augmented reality (AR) consists in the fusion of real-time patient images with a computer-generated 3D virtual patient model created from pre-operative medical imaging. The aim of this prospective pilot study is to investigate the potential of AR navigation as a tool to help locate and surgically resect missing CRLM. A 3D virtual anatomical model was created from thoracoabdominal CT-scans using customary software (VR RENDER(®), IRCAD). The virtual model was superimposed to the operative field using an Exoscope (VITOM(®), Karl Storz, Tüttlingen, Germany). Virtual and real images were manually registered in real-time using a video mixer, based on external anatomical landmarks with an estimated accuracy of 5 mm. This modality was tested in three patients, with four missing CRLM that had sizes from 12 to 24 mm, undergoing laparotomy after receiving pre-operative oxaliplatin-based chemotherapy. AR display and fine registration was performed within 6 min. AR helped detect all four missing CRLM, and guided their resection. In all cases the planned security margin of 1 cm was clear and resections were confirmed to be R0 by pathology. There was no postoperative major morbidity or mortality. No local recurrence occurred in the follow-up period of 6-22 months. This initial experience suggests that AR may be a helpful navigation tool for the resection of missing CRLM.

  4. Construction and Initial Validation of the Multiracial Experiences Measure (MEM)

    Science.gov (United States)

    Yoo, Hyung Chol; Jackson, Kelly; Guevarra, Rudy P.; Miller, Matthew J.; Harrington, Blair

    2015-01-01

    This article describes the development and validation of the Multiracial Experiences Measure (MEM): a new measure that assesses uniquely racialized risks and resiliencies experienced by individuals of mixed racial heritage. Across two studies, there was evidence for the validation of the 25-item MEM with 5 subscales including Shifting Expressions, Perceived Racial Ambiguity, Creating Third Space, Multicultural Engagement, and Multiracial Discrimination. The 5-subscale structure of the MEM was supported by a combination of exploratory and confirmatory factor analyses. Evidence of criterion-related validity was partially supported with MEM subscales correlating with measures of racial diversity in one’s social network, color-blind racial attitude, psychological distress, and identity conflict. Evidence of discriminant validity was supported with MEM subscales not correlating with impression management. Implications for future research and suggestions for utilization of the MEM in clinical practice with multiracial adults are discussed. PMID:26460977

  5. Initial results from the Wisconsin Spherically Convergent Ion Focus experiment

    International Nuclear Information System (INIS)

    Thorson, T.A.; Durst, R.D.; Fonck, R.J.; Foucher, B.S.; Wainwright, L.P.

    1995-01-01

    The Spherically Convergent Ion Focus (SCIF) is an alternative plasma confinement scheme in which ions are electrostatically confined, accelerated, and concentrated at fusion-relevant energies. This concept has been recently promoted for various near-term applications including waste disposal, particle production, neutron radiography and tomography, plastic explosive detection, materials research, and medical isotope production. The Wisconsin SCIF experiments are designed to evaluate the practicality of the SCIF concept for given applications. In the experiment, a wire globe serves as a simple means of producing the trapping potential well and the ion source consists of a cold, uniform plasma at the edge. Hydrogen ions formed from the background neutral gas are typically accelerated to energies of 5--20 kV, and measured cathode grid currents approach the space-charge limit for concentric spheres. Core size measurements utilize spectrally-filtered CCD camera images of the visible emission from the core region, and the minimal observed core radius of 0.6 cm (HWHM) is within a factor of 2--3 of the theoretical convergence ratio for the device. Neutral particle interactions and potential asymmetries imposed by the grid lead to non-ideal convergence, as evidenced by measured potential asymmetries and core size dependence on cathode grid spacing. Floating probes with 30 kV isolation have allowed unique measurements of the density, electric potential and temperature in the converged core. The ratio of core to edge density is 10--20, which is in good agreement with scaling from radial flux conservation

  6. Initial Australian experience with daily ultrasound localisation for prostate radiotherapy

    International Nuclear Information System (INIS)

    Kneebone, A.; Fuller, M.W.; Williams, M.J.

    2003-01-01

    Variability in prostate position is a major problem in the delivery of external beam radiotherapy (EBRT). Daily ultrasound localisation prior to radiotherapy has become popular in the United States but to date has not been used clinically in Australia or New Zealand. Daily transabdominal ultrasound images through the prostate were acquired using the BAT ultrasound system. Contour data from the planning system is reconstructed at the same locations/angles as the BAT images. By overlaying the planned contours with the newly acquired images, the isocentre is adjusted to ensure that the prostate will be within the irradiated volume. After commissioning by Medical Physics, an initial pre-clinical trial period was adopted. This involved performing BAT alignments daily but treating to the planned isocentre in 30 patients. Eighty three percent of patients (25/30) had images judged to be of good or excellent quality by the reviewing radiation oncologist. It was noted that for each operator there was a period needed to build confidence/competence in both imaging and interpreting the images for the moves. The median scan time in addition to the normal patient set-up was 3.2 minutes (range=1.5-12.0 mins) with the second 15 patients scanned quicker than the first 15 (2.9 minutes versus 3.8 minutes). A summary of the movements recommended by the BAT system is contained in the table. We feel that daily prostate ultrasound localization offers a significant advance in delivering EBRT for prostate cancer. The incorporation of the system into clinical use, however, was not without difficulty and requires significant time and effort from therapists, physicists and medical staff. Further clinical evaluation of the unit is ongoing

  7. Social Health Maintenance Organizations: assessing their initial experience.

    Science.gov (United States)

    Newcomer, R; Harrington, C; Friedlob, A

    1990-08-01

    The Social/Health Maintenance Organization (S/HMO) is a four-site national demonstration. This program combines Medicare Part A and B coverage, with various extended and chronic care benefits, into an integrated health plan. The provision of these services extends both the traditional roles of HMOs and that of long-term care community-service case management systems. During the initial 30 months of operation the four S/HMOs shared financial risk with the Health Care Financing Administration. This article reports on this developmental period. During this phase the S/HMOs had lower-than-expected enrollment levels due in part to market competition, underfunding of marketing efforts, the limited geographic area served, and an inability to differentiate the S/HMO product from that of other Medicare HMOs. The S/HMOs were allowed to conduct health screening of applicants prior to enrolling them. The number of nursing home-certifiable enrollees was controlled through this mechanism, but waiting lists were never very long. Persons joining S/HMOs and other Medicare HMOs during this period were generally aware of the alternatives available. S/HMO enrollees favored the more extensive benefits; HMO enrollees considerations of cost. The S/HMOs compare both newly formed HMOs and established HMOs. On the basis of administrator cost, it is more efficient to add chronic care benefits to an HMO than to add an HMO component to a community care provider. All plans had expenses greater than their revenues during the start-up period, but they were generally able to keep service expenditures within planned levels.

  8. PET/MRI in head and neck cancer: initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Platzek, Ivan; Laniado, Michael [Dresden University Hospital, Department of Radiology, Dresden (Germany); Beuthien-Baumann, Bettina [Dresden University Hospital, Department of Nuclear Medicine, Dresden (Germany); Schneider, Matthias [Dresden University Hospital, Oral and Maxillofacial Surgery, Dresden (Germany); Gudziol, Volker [Dresden University Hospital, Department of Otolaryngology, Dresden (Germany); Langner, Jens; Schramm, Georg; Hoff, Joerg van den [Institute of Bioinorganic and Radiopharmaceutical Chemistry, Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany); Kotzerke, Joerg [Dresden University Hospital, Nuclear Medicine, Dresden (Germany)

    2013-01-15

    To evaluate the feasibility of PET/MRI (positron emission tomography/magnetic resonance imaging) with FDG ({sup 18}F-fluorodeoxyglucose) for initial staging of head and neck cancer. The study group comprised 20 patients (16 men, 4 women) aged between 52 and 81 years (median 64 years) with histologically proven squamous cell carcinoma of the head and neck region. The patients underwent a PET scan on a conventional scanner and a subsequent PET/MRI examination on a whole-body hybrid system. FDG was administered intravenously prior to the conventional PET scan (267-395 MBq FDG, 348 MBq on average). The maximum standardized uptake values (SUV{sub max}) of the tumour and of both cerebellar hemispheres were determined for both PET datasets. The numbers of lymph nodes with increased FDG uptake were compared between the two PET datasets. No MRI-induced artefacts where observed in the PET images. The tumour was detected by PET/MRI in 17 of the 20 patients, by PET in 16 and by MRI in 14. The PET/MRI examination yielded significantly higher SUV{sub max} than the conventional PET scanner for both the tumour (p < 0.0001) and the cerebellum (p = 0.0009). The number of lymph nodes with increased FDG uptake detected using the PET dataset from the PET/MRI system was significantly higher the number detected by the stand-alone PET system (64 vs. 39, p = 0.001). The current study demonstrated that PET/MRI of the whole head and neck region is feasible with a whole-body PET/MRI system without impairment of PET or MR image quality. (orig.)

  9. Volume doubling time and growth rate of renal cell carcinoma determined by helical CT: a single-institution experience

    International Nuclear Information System (INIS)

    Lee, Ji Young; Kim, Chan Kyo; Choi, Dongil; Park, Byung Kwan

    2008-01-01

    The purpose of this study was to retrospectively evaluate the volume doubling time (VDT) and growth rate of renal cell carcinomas (RCC) on a serial computed tomography (CT) scan. Thirty pathologically proven RCCs were reviewed with helical CT. Each tumor underwent at least two CT scans. Tumor volume was determined using an area measuring tool and the summation-of-areas technique. Growth rate was evaluated in terms of diameter and volume changes. VDT and volume growth rate were compared in relation to several factors (initial diameter, initial volume, diameter growth rate, volume growth rate, tumor grade, tumor subtype, sex or age). Mean VDT of RCCs was 505 days. Mean diameter and volume growth rate were 0.59 cm/year and 19.1 cm 3 /year, respectively. For volume and diameter growth rate, tumors ≤4 cm showed lower rates than those >4 cm (P 0.05). Volume growth rate was moderately to strongly positively correlated with initial diameter, initial volume and diameter growth rate (P < 0.05). In conclusion, small RCCs grew at a slow rate both diametrically and volumetrically. More accurate assessment of tumor growth rate and VDT may be helpful to understand the natural history of RCC. (orig.)

  10. Optimizing CT angiography in patients with Fontan physiology: single-center experience of dual-site power injection

    International Nuclear Information System (INIS)

    Sandler, K.L.; Markham, L.W.; Mah, M.L.; Byrum, E.P.; Williams, J.R.

    2014-01-01

    Aim: To identify adult patients with single-ventricle congenital heart disease and Fontan procedure palliation who have been misdiagnosed with or incompletely evaluated for pulmonary embolism. Additionally, this study was designed to demonstrate that simultaneous, dual-injection of contrast medium into an upper and lower extremity vein is superior to single-injection protocols for CT angiography (CTA) of the chest in this population. Materials and methods: Patients included in the study were retrospectively selected from the Adult Congenital Heart Disease (ACHD) database. Search criteria included history of Fontan palliation and available chest CT examination. Patients were evaluated for (1) type of congenital heart disease and prior operations;(2) indication for initial CT evaluation;(3) route of contrast medium administration for the initial CT examination and resulting diagnosis;(4) whether or not anticoagulation therapy was initiated; and (5) final diagnosis and treatment plan. Results: The query of the ACHD database resulted in 28 individuals or patients with Fontan palliation (superior and inferior venae cavae anastomosed to the pulmonary arteries). Of these, 19 patients with Fontan physiology underwent CTA of the pulmonary circulation, and 17 had suboptimal imaging studies. Unfortunately, seven of these 17 patients (41%) were started on anticoagulation therapy due to a diagnosis of pulmonary embolism that was later excluded. Conclusion: Patients with single-ventricle/Fontan physiology are at risk of thromboembolic disease. Therefore, studies evaluating their complex anatomy must be performed with the optimal imaging protocol to ensure diagnostic accuracy, which is best achieved with dual-injection of an upper and lower extremity central vein. - Highlights: • The adult congenital heart disease population is growing. • Many of these patients have single ventricle/Fontan physiology. • Patients with Fontan physiology are at increased risk for

  11. Patient experience of CT colonography and colonoscopy after fecal occult blood test in a national screening programme

    OpenAIRE

    Plumb, Andrew A.; Ghanouni, Alex; Rees, Colin J.; Hewitson, Paul; Nickerson, Claire; Wright, Suzanne; Taylor, Stuart A.; Halligan, Steve; von Wagner, Christian

    2016-01-01

    Objective To investigate patient experience of CT colonography (CTC) and colonoscopy in a national screening programme. Methods Retrospective analysis of patient experience postal questionnaires. We included screenees from a fecal occult blood test (FOBt) based screening programme, where CTC was performed when colonoscopy was incomplete or deemed unsuitable. We analyzed questionnaire responses concerning communication of test risks, test-related discomfort and post-test pain, as well as compl...

  12. Patient experience of CT colonography and colonoscopy after fecal occult blood test in a national screening programme

    OpenAIRE

    Plumb, A. A.; Ghanouni, A.; Rees, C. J.; Hewitson, P.; Nickerson, C.; Wright, S.; Taylor, S. A.; Halligan, S.; von Wagner, C.

    2017-01-01

    OBJECTIVE: To investigate patient experience of CT colonography (CTC) and colonoscopy in a national screening programme. METHODS: Retrospective analysis of patient experience postal questionnaires. We included screenees from a fecal occult blood test (FOBt) based screening programme, where CTC was performed when colonoscopy was incomplete or deemed unsuitable. We analyzed questionnaire responses concerning communication of test risks, test-related discomfort and post-test pain, as well as com...

  13. Initial experience of the medical clinic of the education Casmu

    International Nuclear Information System (INIS)

    Musé, M.; Laureiro, E.; Musetti, C.

    2010-01-01

    Full text: What happens when a patient (p te) is faced once treatment Q T? We know that for p te involves both how their family; face a charge of myths and half-truths; causing the treatment is so vivid apprehension as the disease itself. In this context the concern of the Department of Oncology Casmu arises; of give patients an area where the p te to receive information contribute to reaching the treatment of Q T in better condition. All patients will start treatment Q T for the first time; are cited for an interview at the Polyclinic of Education. It is coordinated delayed with respect to the talks with the Treating oncologist, in order to allow the patient to develop their doubts and to raise them. In the interview also involved the p te and his family, Oncology Residents Department, and a member of Campus Nursing thereof. the interview is divided into five modules: 1) Administrative Aspects 2) Nursing Care 3) Potential side effects. 4) Social Benefits 5) Resources Information. Between January 2003 and August 2004, 70 interviews were conducted education. the average length thereof was 30 minutes. Is in progress writing a brochure based on the questions most frequently asked by patients and their families; well as an evaluation of the experience

  14. Magnetic resonance imaging of the female pelvis: initial experience

    International Nuclear Information System (INIS)

    Hricak, H.; Alpers, C.; Crooks, L.E.; Sheldon, P.E.

    1983-01-01

    The potential of magnetic resonance imaging (MRI) was evaluated in 21 female subjects: seven volunteers, 12 patients scanned for reasons unrelated to the lower genitourinary tract, and two patients referred with gynecologic disease. The uterus at several stages was examined; the premenarcheal uterus (one patient), the uterus of reproductive age (12 patients), the postmenopausal uterus (two patients), and in an 8 week pregnancy (one patient). The myometrium and cyclic endometrium in the reproductive age separated by a low-intensity line (probably stratum basale), which allows recognition of changes in thickness of the cyclic endometrium during the menstrual cycle. The corpus uteri can be distinguished from the cervix by the transitional zone of the isthmus. The anatomic relation of the uterus to bladder and rectum is easily outlined. The vagina can be distinguished from the cervix, and the anatomic display of the closely apposed bladder, vagina, and rectum is clear on axial and coronal images. The ovary is identified; the signal intensity from the ovary depends on the acquisition parameter used. Uterine leiomyoma, endometriosis, and dermoid cyst were depicted, but further experience is needed to ascertain the specificity of the findings

  15. Initial experience with a nuclear medicine viewing workstation

    Science.gov (United States)

    Witt, Robert M.; Burt, Robert W.

    1992-07-01

    Graphical User Interfaced (GUI) workstations are now available from commercial vendors. We recently installed a GUI workstation in our nuclear medicine reading room for exclusive use of staff and resident physicians. The system is built upon a Macintosh platform and has been available as a DELTAmanager from MedImage and more recently as an ICON V from Siemens Medical Systems. The workstation provides only display functions and connects to our existing nuclear medicine imaging system via ethernet. The system has some processing capabilities to create oblique, sagittal and coronal views from transverse tomographic views. Hard copy output is via a screen save device and a thermal color printer. The DELTAmanager replaced a MicroDELTA workstation which had both process and view functions. The mouse activated GUI has made remarkable changes to physicians'' use of the nuclear medicine viewing system. Training time to view and review studies has been reduced from hours to about 30-minutes. Generation of oblique views and display of brain and heart tomographic studies has been reduced from about 30-minutes of technician''s time to about 5-minutes of physician''s time. Overall operator functionality has been increased so that resident physicians with little prior computer experience can access all images on the image server and display pertinent patient images when consulting with other staff.

  16. Application of robotics in general surgery: initial experience.

    Science.gov (United States)

    Nguyen, Ninh T; Hinojosa, Marcelo W; Finley, David; Stevens, Melinda; Paya, Mahbod

    2004-10-01

    Robotic surgery was recently approved for clinical use in general abdominal surgery. The aim of this study was to review our experience with the da Vinci surgical system during laparoscopic general surgical procedures. Eighteen patients underwent robotically assisted laparoscopic abdominal surgery between June 2002 and March 2003. Main outcome measures were operative time, room setup time, robotic arm-positioning and surgical time, blood loss, conversion to laparoscopy, length of stay, and morbidity. The types of robotically assisted laparoscopic procedures were excision of gastric leiomyoma (n = 1), Heller myotomy (n = 1), cholecystectomy (n = 2), gastric banding (n = 2), Nissen fundoplication (n = 4), and gastric bypass (n = 8). The mean room setup time was 63 +/- 14 minutes, and the mean robotic arm-positioning time was 16 +/- 7 minutes. Conversion to laparoscopy occurred in two (11%) of 18 cases because of equipment difficulty (n = 1) and technical difficulty (n = 1). Estimated blood loss was 91 +/- 71 mL. The mean operative time was 156 +/- 42 minutes, and the robotic operative time was 27% of the total operative time. The mean length of hospital stay was 2.2 +/- 1.5 days. There was one postoperative wound infection and one anastomotic stricture. Robotically assisted laparoscopic abdominal surgery is feasible and safe; however, the theoretical advantages of the da Vinci surgical system were not clinically apparent.

  17. Dual-source CT coronary angiography in patients with premature heart-beats: initial experience

    International Nuclear Information System (INIS)

    Wang Yining; Zhang Zhuhua; Kong Lingyan; Song Lan; Mu Wenbin; Wang Yun; Jin Zhengyu

    2008-01-01

    Objective: To evaluate the feasibility of dual-source computed tomography (DSCT) coronary angiography in a population with premature heart-beats. Methods: Seventy patients with suspected coronary artery disease and premature heart-beats were routinely imaged on a DSCT scanner (Somatom Definition, Siemens AG, Germany). The images were reconstmcted before and after ECG editing. Two readers independently assessed image quality of all coronary segments using a four-point grading scale from excellent (1) to non-assessable (4). The results of the two groups were compared with a paired t-test, and a P value of less than 0.05 was considered significant. Results: The mean heart rate during examination ranged from 49 to 111 bpm[ mean(70.7±12.4) bpm]. Twenty-eight of 70 patients with relatively small variability of the heart rate [(41.0±18.4) bpm] got diagnostic image quality without ECG editing. In other 42 patients with larger variability of the heart rate [(71.4±28.7) bpm], the mean image quality scores were 2.09±1.27 and 1.50±0.79 before and after ECG editing, there was a significant difference (t= 13.764, P 2 =121.846, P<0.01). Finally, the diagnostic image accounted 98.0% (1014/1035) in all segments of 70 patients. Conclusion: DSCT can provide diagnostic images for patients with premature heart-beats. The image quality in patients with larger variability of the heart rate can be significantly improved through ECG editing. (authors)

  18. Breast vibro-acoustography: initial experience in benign lesions

    International Nuclear Information System (INIS)

    Alizad, Azra; Mehrmohammadi, Mohammad; Ghosh, Karthik; Glazebrook, Katrina N; Carter, Rickey E; Karaberkmez, Leman Gunbery; Whaley, Dana H; Fatemi, Mostafa

    2014-01-01

    Vibro-acoustography (VA) is a newly developed imaging technology that is based on low-frequency vibrations induced in the object by the radiation force of ultrasound. VA is sensitive to the dynamic characteristics of tissue. Here, we evaluate the performance of VA in identifying benign lesions and compare the results to those of mammography. An integrated mammography-VA system designed for in vivo breast imaging was tested on a group of female volunteers, age ≥ 18 years, with suspected breast lesions based on clinical examination. A set of VA scans was acquired after each corresponding mammography. Most lesions were classified as benign based on their histological results. However, in 4 cases, initial diagnosis based on clinical imaging determined that the lesions were cysts. These cysts were aspirated with needle aspiration and disappeared completely under direct ultrasound visualization. Therefore, no biopsies were performed on these cases and lesions were classified as benign based on clinical findings per clinical standards. To define the VA characteristics of benign breast masses, we adopted the features that are normally attributed to such masses in mammography. In a blinded assessment, three radiologists evaluated the VA images independently. The diagnostic accuracy of VA for detection of benign lesions was assessed by comparing the reviewers’ evaluations with clinical data. Out of a total 29 benign lesions in the group, the reviewers were able to locate all lesions on VA images and mammography, 100% with (95% confidence interval (CI): 88% to 100%). Two reviewers were also able to correctly classify 83% (95% CI: 65% to 92%), and the third reviewer 86% (95% CI: 65% to 95%) of lesions, as benign on VA images and 86% (95% CI: 69% to 95%) on mammography. The results suggest that the mammographic characteristics of benign lesion may also be used to identify such lesions in VA. Furthermore, the results show the ability of VA to detect benign breast

  19. Digital breast tomosynthesis (DBT): initial experience in a clinical setting

    International Nuclear Information System (INIS)

    Skaane, Per; Gullien, Randi; Eben, Ellen B.; Haakenaasen, Unni; Naess Jebsen, Ingvild; Krager, Mona; Bjoerndal, Hilde; Ekseth, Ulrika; Jahr, Gunnar

    2012-01-01

    false-positive findings. The side-by-side feature analysis showed higher conspicuity scores for tomosynthesis compared to conventional 2D for cancers presenting as spiculated masses and distortions. Conclusion: Tomosynthesis is a promising new technique. Our preliminary clinical experience shows that there is a potential for increasing the sensitivity using this new technique, especially for cancers manifesting as spiculated masses and distortions

  20. First experience of combined cardiac PET/64-detector CT angiography with invasive angiographic validation

    International Nuclear Information System (INIS)

    Groves, Ashley M.; Kayani, Irfan; Endozo, Raymondo; Menezes, Leon J.; Prvulovich, Elizabeth; Ell, Peter J.; Speechly-Dick, Marie-Elsya; McEwan, Jean; Pugliese, Francesca; Habib, Said B.

    2009-01-01

    Despite modern CT systems and expert evaluators, the diagnostic performance of coronary CT angiography is limited by overestimation of vessel stenosis which reduces the positive predictive value (PPV) of the test. The aim of this study was to evaluate the performance of combined cardiac PET/64-detector CT angiography. Included in this retrospective study were 33 consecutive patients (5 women, 28 men; mean age 61.6 years, range 47-87 years, mean BMI 27.3±5.2 kg/m 2 ) with clinically suspected flow-limiting coronary artery disease who underwent combined cardiac PET/64-detector CT angiography and invasive angiography. Combined PET/CT images were reported by an experienced dual-accredited radiologist/nuclear physician. An experienced cardiac CT radiologist re-read the CT images without PET. Stenotic disease was defined as >50% vessel narrowing. Invasive coronary angiography was used as a reference standard. Local ethics committee approval and patient consent were obtained. CT angiography (without PET data) was concordant with invasive angiography in 31/33 patients and at a patient level, the sensitivity in detecting significant coronary artery lesions was 100%, the specificity was 82%, the PPV was 92% and the negative predictive value (NPV) was 100%. Using combined PET/CT angiography the findings were concordant with invasive angiography in 32/33 patients and at a patient level, the sensitivity was 96%, the specificity was 100%, the PPV was 100% and the NPV was 91%. The use of integrated cardiac PET/64-detector CT angiography is feasible and appears to improve some aspects of the diagnostic performance of 64-detector coronary artery angiography in detecting coronary artery disease. (orig.)

  1. Negative Interest Rates: Central Banks Initiated an Experiment

    Directory of Open Access Journals (Sweden)

    Aleksey N. Burenin

    2016-01-01

    Full Text Available Negative interest rates appeared as a consequence of economic problems that countries with market economy came across after the crises of2007-2008. The attempts of monetary authorities to stimulate economies with the help of quantitative easing didn't bring the desired result. That's why the central banks once again resorted to a traditional tool of their monetary policy of changing interest rates. But this time they launched an experiment, they used negative interest rates. The European Central Bank, the Swedish Riksbank, the Bank of Japan, and the National Bank of Hungary introduced negative rates in order to stimulate economic growth and fight the threat of deflation, the Danish National Bank and the Swiss National Bank tried to deter appreciation of their currencies. Negative rates of the central banks brought about negative yields of government and nongovernment securities in several countries. The problem acquires an aggravated form due to the fact that negative rates appeared in several European countries simultaneously at the moment when global financial markets were not in crises. Some questions arise concerning the negative rates, for example, how low can central banks bring down the rates in the future, what is their influence on the stock markets, what is the reaction of depositors to the introduction of negative deposit rates by commercial banks, must one consider a negative rate as a rate of interest or payment to store money of the depositor, in which circumstances negative rates can be justified to fight deflation. The last question plays an important role, because recent studies find that positive economic growth is possible during deflation. If central banks don't take this nuance into consideration, they can create economic imbalances by increasing liquidity. Negative rates are not as inoffensive as it may seem at first glance. Not far ago an investor, who tried to averse risk, was buying government securities. Their yields

  2. Hepatic trauma: CT findings and considerations based on our experience in emergency diagnostic imaging

    International Nuclear Information System (INIS)

    Romano, Luigia; Giovine, Sabrina; Guidi, Guido; Tortora, Giovanni; Cinque, Teresa; Romano, Stefania

    2004-01-01

    Abdominal blunt trauma represents the main cause of death in people of age less than 40 years; the liver injury occurs frequently, with an incidence varying from 3 to 10%. Isolated hepatic lesions are rare and in 77-90% of cases, lesions of other organs and viscera are involved. Right hepatic lobe is a frequent site of injury, because it is the more voluminous portion of liver parenchyma; posterior superior hepatic segments are proximal to fixed anatomical structures such as ribs and spine that may have an important role in determining of the lesion. The coronal ligaments' insertion in this parenchymal region augments the effect of acceleration-deceleration mechanism. Associated lesions usually are homolateral costal fractures, laceration or contusion of the inferior right pulmonary lobe, haemothorax, pneumothorax, renal and/or adrenal lesions. Traumatic lesions of left hepatic lobe are rare and usually associated with direct impact on the superior abdomen, such as in car-crash when the wheel causes a compressive effect on thorax and abdomen. Associated lesions to left hepatic lobe injuries correlated to this mechanism are: sternal fractures, pancreatic, myocardial, gastrointestinal tract injuries. Lesions of the caudal lobe are extremely rare, usually not isolated and noted with other large parenchymal lesions. The Institution of Specialized Trauma Centers and the technical progress in imaging methodology developed in the last years a great reduction of mortality. New diagnostic methodologies allow a reduction of negatives laparotomies and allow the possibility of conservative treatment of numerous traumatic lesions; however, therapy depends from imaging findings and clinical conditions of the patient. Computed tomography (CT) certainly presents a large impact on diagnosis and management of patients with lesions from blunt abdominal traumas. It is important to establish a prognostic criteria allowing decisions for conservative or surgical treatment; CT findings

  3. Hepatic trauma: CT findings and considerations based on our experience in emergency diagnostic imaging

    Energy Technology Data Exchange (ETDEWEB)

    Romano, Luigia; Giovine, Sabrina; Guidi, Guido; Tortora, Giovanni; Cinque, Teresa; Romano, Stefania E-mail: stefromano@libero.it

    2004-04-01

    Abdominal blunt trauma represents the main cause of death in people of age less than 40 years; the liver injury occurs frequently, with an incidence varying from 3 to 10%. Isolated hepatic lesions are rare and in 77-90% of cases, lesions of other organs and viscera are involved. Right hepatic lobe is a frequent site of injury, because it is the more voluminous portion of liver parenchyma; posterior superior hepatic segments are proximal to fixed anatomical structures such as ribs and spine that may have an important role in determining of the lesion. The coronal ligaments' insertion in this parenchymal region augments the effect of acceleration-deceleration mechanism. Associated lesions usually are homolateral costal fractures, laceration or contusion of the inferior right pulmonary lobe, haemothorax, pneumothorax, renal and/or adrenal lesions. Traumatic lesions of left hepatic lobe are rare and usually associated with direct impact on the superior abdomen, such as in car-crash when the wheel causes a compressive effect on thorax and abdomen. Associated lesions to left hepatic lobe injuries correlated to this mechanism are: sternal fractures, pancreatic, myocardial, gastrointestinal tract injuries. Lesions of the caudal lobe are extremely rare, usually not isolated and noted with other large parenchymal lesions. The Institution of Specialized Trauma Centers and the technical progress in imaging methodology developed in the last years a great reduction of mortality. New diagnostic methodologies allow a reduction of negatives laparotomies and allow the possibility of conservative treatment of numerous traumatic lesions; however, therapy depends from imaging findings and clinical conditions of the patient. Computed tomography (CT) certainly presents a large impact on diagnosis and management of patients with lesions from blunt abdominal traumas. It is important to establish a prognostic criteria allowing decisions for conservative or surgical treatment; CT

  4. CT colonography without cathartic preparation: positive predictive value and patient experience in clinical practice

    Energy Technology Data Exchange (ETDEWEB)

    Zueco Zueco, Carmen; Sobrido Sampedro, Carolina; Corroto, Juan D.; Rodriguez Fernandez, Paula; Fontanillo Fontanillo, Manuela [Complexo Hospitalario Universitario de Vigo - CHUVI, Vigo, Pontevedra (Spain)

    2012-06-15

    To determine the positive predictive value (PPV) for polyps {>=}6 mm detected at CT colonography (CTC) performed without cathartic preparation, with low-dose iodine faecal tagging regimen and to evaluate patient experience. 1920 average-risk patients underwent CTC without cathartic preparation. Faecal tagging was performed by diatrizoate meglumine and diatrizoate sodium at a total dose of 60 ml (22.2 g of iodine).The standard interpretation method was primary 3D with 2D problem solving. We calculated per-patient and per-polyp PPV in relation to size and morphology. All colonic segments were evaluated for image quality (faecal tagging, amount of liquid and solid residual faeces and luminal distension). Patients completed a questionnaire before and after CTC to assess preparation and examination experience. Per-polyp PPV for detected lesions of {>=}6 mm, 6-9 mm, {>=}10 mm and {>=}30 mm were 94.3%, 93.1%, 94.7% and 98%, respectively. Per-polyp PPV, according to lesion morphology, was 94.6%, 97.3% and 85.1% for sessile, pedunculated and flat polyps, respectively. Per-patient PPV was 92.8%. Preparation without frank cathartics was reported to cause minimal discomfort by 78.9% of patients. CTC without cathartic preparation and low-dose iodine faecal tagging may yield high PPVs for lesions {>=}6 mm and is well accepted by patients. circle Computed tomographic colonography (CTC) without cathartic preparation is well accepted by patients circle Cathartic-free faecal tagging CTC yields high positive predictive values circle CTC without cathartic preparation could improve uptake of colorectal cancer screening. (orig.)

  5. Multislice CT cholangiography without biliary contrast agent: technique and initial clinical results in the assessment of patients with biliary obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Zandrino, F.; Benzi, L.; Ferretti, M.L.; Ferrando, R.; Reggiani, G.; Musante, F. [Department of Radiology, Azienda Ospedaliera ' ' SS Antonio e Biagio e C. Arrigo' ' , Alessandria (Italy)

    2002-05-01

    Our objective was to describe our technique for multislice CT cholangiography without cholangiographic contrast agent, and to present our preliminary clinical results. Thirty-seven patients with suspected biliary obstruction were studied. A multislice CT unit was used with the following technical parameters: 2.5-mm collimation; 7.5-mm/s table speed; pitch 6; 0.8-s rotation time; 300 mA; 120 kVp; 18- to 24-s scan time; scan volume ranging from the hepatic dome to below the pancreatic head; 70-s delay after injection of 150 ml of iodinated contrast agent at 4 ml/s. No biliary contrast material was given; oral iodinated contrast agent was administered to opacify bowel loops. Axial, multiplanar reformatted, and minimum intensity projection images were evaluated. The CT findings were compared with the gold standard techniques: endoscopic retrograde cholangiography (ERCP) in 30 patients, percutaneous transhepatic cholangiography in 5, and intraoperative cholangiography in 2. In 5 patients with ampullary lesions biopsy was made during ERCP, 9 underwent surgery, and 11 US-guided fine-needle aspiration. Bile ducts appeared hypodense within the surrounding enhanced structures. Regarding the site of obstruction, agreement between multislice CT and conventional cholangiography was observed in all cases. One patient presented negative findings on both CT and ERCP. In 31 of 36 (86%) patients, multislice CT cholangiography without cholangiographic contrast agent correctly assessed the cause of bile duct obstruction. Multislice CT cholangiography without cholangiographic contrast agent seems to be a promising diagnostic tool in the assessment of patients with bile duct obstruction. (orig.)

  6. Multislice CT cholangiography without biliary contrast agent: technique and initial clinical results in the assessment of patients with biliary obstruction

    International Nuclear Information System (INIS)

    Zandrino, F.; Benzi, L.; Ferretti, M.L.; Ferrando, R.; Reggiani, G.; Musante, F.

    2002-01-01

    Our objective was to describe our technique for multislice CT cholangiography without cholangiographic contrast agent, and to present our preliminary clinical results. Thirty-seven patients with suspected biliary obstruction were studied. A multislice CT unit was used with the following technical parameters: 2.5-mm collimation; 7.5-mm/s table speed; pitch 6; 0.8-s rotation time; 300 mA; 120 kVp; 18- to 24-s scan time; scan volume ranging from the hepatic dome to below the pancreatic head; 70-s delay after injection of 150 ml of iodinated contrast agent at 4 ml/s. No biliary contrast material was given; oral iodinated contrast agent was administered to opacify bowel loops. Axial, multiplanar reformatted, and minimum intensity projection images were evaluated. The CT findings were compared with the gold standard techniques: endoscopic retrograde cholangiography (ERCP) in 30 patients, percutaneous transhepatic cholangiography in 5, and intraoperative cholangiography in 2. In 5 patients with ampullary lesions biopsy was made during ERCP, 9 underwent surgery, and 11 US-guided fine-needle aspiration. Bile ducts appeared hypodense within the surrounding enhanced structures. Regarding the site of obstruction, agreement between multislice CT and conventional cholangiography was observed in all cases. One patient presented negative findings on both CT and ERCP. In 31 of 36 (86%) patients, multislice CT cholangiography without cholangiographic contrast agent correctly assessed the cause of bile duct obstruction. Multislice CT cholangiography without cholangiographic contrast agent seems to be a promising diagnostic tool in the assessment of patients with bile duct obstruction. (orig.)

  7. (18F) FDG PET/CT in patients with fever of unknown origin: AIIMS experience

    International Nuclear Information System (INIS)

    Nazar, A.H.; Naswa, N.; Ramya, S.; Patnecha, M.; Bangkim, Chandra K.H.; Kumar, R.; Bandopadhyay, G.P.; Bal, C.S.; Malhotra, A.

    2010-01-01

    Full text: The aim of this study was to assess the value of ( 18 F) FDG PET/CT in evaluation of patients with Fever of Unknown Origin (FUO). We retrospectively analysed clinical data and ( 18 F) FDG PET scan of 48 patients over a period of 1 year. These patients met the revised definition criteria of FUO (febrile illness of greater than 3 weeks duration, temperature greater than 38.3 C and no diagnosis after appropriate in-patient or out-patient evaluation). Most of the patients recruited in this study had normal clinical and radiological examination. ( 18 F) FDG PET was helpful in making a diagnosis in 24 patients. An infective/inflammatory cause of FUO was found in thirteen (27%) patients, a neoplasm in six (12.5%) patients, autoimmune cause in five (10.4%) patients. A definitive diagnosis could not be made in twenty four (50%) patients. Out of these 24 patients, 15 had normal PET/CT study, 9 had positive PET/CT findings but they lost in follow up and 2 died within 1 month of PET/CT study without any diagnosis. ( 18 F) FDG PET/CT is a useful tool for evaluation of patients with FUO. It provides important diagnostic clues not suggested by other conventional imaging modalities. Patients with positive PET/CT findings but no definitive diagnosis should be followed up further to improve utility of PET/CT

  8. Post transplant lymphoproliferative disease in pediatric solid organ transplant patients: A possible role for [{sup 18}F]-FDG-PET(/CT) in initial staging and therapy monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Falck, C. von [Department of Diagnostic Radiology, Medizinische Hochschule Hannover (Medical School Hanover), Carl-Neuberg-Strasse 1, 30625 Hannover (Germany)], E-mail: Falck.Christian.von@mh-hannover.de; Maecker, B. [Department of Pediatric Hematology and Oncology, Medizinische Hochschule Hannover (Medical School Hanover), Carl-Neuberg-Strasse 1, 30625 Hannover (Germany); Schirg, E. [Department of Diagnostic Radiology, Medizinische Hochschule Hannover (Medical School Hanover), Carl-Neuberg-Strasse 1, 30625 Hannover (Germany); Boerner, A.R.; Knapp, W.H. [Department of Nuclear Medicine, Medizinische Hochschule Hannover (Medical School Hanover), Carl-Neuberg-Strasse 1, 30625 Hannover (Germany); Klein, C. [Department of Pediatric Hematology and Oncology, Medizinische Hochschule Hannover (Medical School Hanover), Carl-Neuberg-Strasse 1, 30625 Hannover (Germany); Galanski, M. [Department of Diagnostic Radiology, Medizinische Hochschule Hannover (Medical School Hanover), Carl-Neuberg-Strasse 1, 30625 Hannover (Germany)

    2007-09-15

    Post transplant lymphoproliferative disease (PTLD) is a severe complication after solid organ or bone marrow transplantation. In pediatric transplant recipients PTLD is the most common malignancy. The aim of this study was to evaluate a possible role for positron emission tomography with [{sup 18}F]-2-fluoro-2-desoxy-glucose (FDG) in the initial staging and in therapy monitoring of pediatric patients suffering from biopsy-proven CD20-positive PTLD after solid organ transplantation. Seven pediatric patients were included. All available imaging studies - CT (n = 15), MRI (n = 16) and PET/PETCT (n = 16) - were reviewed on a lesion by lesion base. The performance of FDG-PET in the initial staging and during therapy with a chimeric anti-CD20 antibody was compared to conventional cross sectional imaging and correlated with the clinical outcome. FDG-PET identified all sites of disease as shown by CT/MRI and helped to clarify the significance of equivocal findings. The initial stage of disease was correctly identified by FDG-PET alone when compared to CT/MRI. During therapy, FDG-PET was superior to conventional cross-sectional imaging in the early evaluation of response.

  9. An experience on the opacificated CT picture with lumbar selective radiculography

    International Nuclear Information System (INIS)

    Yoshida, Tsunemaru; Tanaka, Hideaki; Moriyama, Takeo; Sugiyama, Teruo.

    1982-01-01

    CT was undergone in the cases in which vertebral canal stenosis was suspected. In CT findings, the semicircle of the epidural cavity and the anterolateral surface were visualized as opacificated images, but the vertebral canal sometimes was not visualized, depending on the degree of stenosis. Reconstruction of an image of the ossific vertebral canal seemed to be possible by utilizing the data of the sagittal diameter, form, and CBR of the vertebral canal. Findings of opacificated CT pictures in comparison with other data of roentgenography are useful in searching the causes of vertebral stenosis. (Chiba, N.)

  10. Local Control of Perivascular Malignant Liver Lesions Using Percutaneous Irreversible Electroporation: Initial Experiences

    Energy Technology Data Exchange (ETDEWEB)

    Eller, Achim, E-mail: Achim.Eller@uk-erlangen.de; Schmid, Axel, E-mail: axel.schmid@uk-erlangen.de [University Hospital Erlangen, University of Erlangen-Nuremberg, Department of Radiology (Germany); Schmidt, Joachim, E-mail: joachim.schmidt@kfa.imed.uni-erlangen.de [University Hospital Erlangen, University of Erlangen-Nuremberg, Department of Anesthesiology (Germany); May, Matthias, E-mail: matthias.may@uk-erlangen.de; Brand, Michael, E-mail: michael.brand@uk-erlangen.de; Saake, Marc, E-mail: marc.saake@uk-erlangen.de; Uder, Michael, E-mail: michael.uder@uk-erlangen.de; Lell, Michael, E-mail: michael.lell@uk-erlangen.de [University Hospital Erlangen, University of Erlangen-Nuremberg, Department of Radiology (Germany)

    2015-02-15

    PurposeThis study was designed to assess efficacy and safety in the treatment of perivascular malignant liver lesions using percutaneous, computed tomography (CT)-guided irreversible electroporation (IRE).MethodsFourteen patients (mean age 58 ± 11 years) with 18 malignant liver lesions were consecutively enrolled in this study. IRE was performed in patients not eligible for surgery and lesions abutting large vessels or bile ducts. Follow-up exams were performed using multislice-CT (MS-CT) or MRI.ResultsMedium lesion diameter was 20 ± 5 mm. Ten of 14 (71 %) were successfully treated with no local recurrence to date (mean follow-up 388 ± 160 days). One case left initial tumor control unclear and additional RFA was performed 4 weeks after IRE. Complications occurred in 4 of 14 (29 %) cases. In one case, intervention was terminated and abdominal bleeding required laparotomy. In two cases, a postinterventional hematothorax required intervention. In another case, abdominal bleeding could be managed conservatively. No complications related to the bile ducts occurred.ConclusionsPercutaneous IRE seems to be effective in perivascular lesions but is associated with a higher complication rate compared with thermoablative techniques.

  11. Screening in asymptomatic SDHx mutation carriers: added value of {sup 18}F-FDG PET/CT at initial diagnosis and 1-year follow-up

    Energy Technology Data Exchange (ETDEWEB)

    Lepoutre-Lussey, C.; Deandreis, D.; Berdelou, A.; Nascimento, C.; Lumbroso, J.; Schlumberger, M.; Baudin, E.; Leboulleux, S. [Gustave Roussy Institut, Universite Paris-Sud, Department of Nuclear Medicine and Endocrine Oncology, Villejuif (France); Caramella, C.; Bidault, F.; Deschamps, F. [Gustave Roussy Institut, Department of Radiology, Villejuif (France); Al Ghuzlan, A. [Gustave Roussy Institut, Department of Medical Biology and Pathology, Villejuif (France); Hartl, D.; Dumont, F. [Gustave Roussy Institut, Department of Surgery, Villejuif (France); Borget, I. [Gustave Roussy Institut, Department of Biostatistic and Epidemiology, Villejuif (France); Paris-Sud University, Villejuif (France); Gimenez-Roqueplo, A.P. [Assistance Publique-Hopitaux de Paris, Hopital Europeen Georges Pompidou, Department of Genetics, Paris (France); Paris Descartes University, Faculty of Medicine, Paris (France); Guillaud Bataille, M. [Gustave Roussy Institut, Department of Genetics, Villejuif (France)

    2015-05-01

    Specific recommendations on screening modalities for paraganglioma (PGL) and phaeochromocytoma (PCC) in asymptomatic SDHx mutation carriers (relatives) are still lacking. We evaluated the added value of {sup 18}F-FDG PET/CT in comparison with morphological imaging at initial diagnosis and 1 year of follow-up in this population. The study included 30 consecutive relatives with a proven SDHx mutation who were investigated by {sup 18}F-FDG PET/CT, gadolinium-enhanced magnetic resonance angiography of the head and neck, thoracic/abdominal/pelvic (TAP) contrast-enhanced CT and/or TAP MRI. {sup 123}I-MIBG scintigraphy was performed in 20 subjects and somatostatin receptor scintigraphy (SRS) in 20 subjects. The gold standard was based on pathology or a composite endpoint as defined by any other positive imaging method and persistent tumour on follow-up. Images were considered as false-positive when the lesions were not detected by another imaging method or not confirmed at 1 year. At initial work-up, an imaging abnormality was found in eight subjects (27 %). The final diagnosis was true-positive in five subjects (two with abdominal PGL, one with PCC and two with neck PGL) and false-positives in the other three subjects (detected with {sup 18}F-FDG PET/CT in two and TAP MRI in one). At 1 year, an imaging abnormality was found in three subjects of which one was an 8-mm carotid body PGL in a patient with SDHD mutation and two were considered false-positive. The tumour detection rate was 100 % for {sup 18}F-FDG PET/CT and conventional imaging, 80 % for SRS and 60 % for {sup 123}I-MIBG scintigraphy. Overall, disease was detected in 4 % of the subjects at the 1-year follow-up. {sup 18}F-FDG PET/CT demonstrated excellent sensitivity but intermediate specificity justifying combined modality imaging in these patients. Given the slow progression of the disease, if {sup 18}F-FDG PET/CT and MRI are normal at baseline, the second imaging work-up should be delayed and an examination

  12. Early experience with a picture archiving and communication system for X-ray CT

    International Nuclear Information System (INIS)

    Nakano, Y.; Komori, M.; Minato, K.

    1987-01-01

    A network using fiberoptic ring architecture has been implemented to connect an x-ray CT unit with an image work station and optical disk storage unit. The work station has three noninterlaced cathode-ray tube (CRT) monitors of 1,024 X 1,024 pixels. The optical disk system stores 32 optical disk cartridges (2.6 Gbytes per cartridge). A general-purpose interface bus is used for communication between the CT unit and the network interface unit. Transfer time from CT to interface unit is 40 kbyte/second, 5 seconds per image. On-line data acquisition, long-term archiving, and CT interpretation using CRTs have been tested and the system has been working for 3 months in a clinical environment

  13. Clinical experience of titanium cerebral aneurysm clips. Evaluation of artifact of CT and MRI

    International Nuclear Information System (INIS)

    Ninomiya, Takashi; Kato, Yoko; Sano, Hirotoshi

    1996-01-01

    The titanium aneurysm clips manufactured by AESCULAP Company are expected to be useful, not only for clinical applications, but also for reducing artifacts in post-operative CT and MRI. We carried out an investigation of the behavior of the new Yasargil titanium clips in a 1.5T MR imager. The new titanium clips showed considerably smaller clip-induced MR and CT artifacts than phynox and elgiloy clips. No movement of the titanium clips was seen by introducing them to the MR imager. Subsequent to these experimental studies, we applied titanium clips to 25 cerebral aneurysms. Post-operative CT, especially helical scanning CT and MR showed minimal artifacts, leading to the conclusion that the titanium clips are better than the other types of clips for the evaluation of post-operative neuroradiological images. (author)

  14. The initial experience of trans-rectal ultrasound and biopsy in ...

    African Journals Online (AJOL)

    The initial experience of trans-rectal ultrasound and biopsy in diagnosis of carcinoma prostate in Gezira Hospital for Renal Disease and Surgery (GHRDS). Walaa Eldin Ibraheem, Sami Mahjoub Taha, Mustafa Omran Mansour, Mohammed El Imam Mohamed Ahmed ...

  15. The Community Reclaims Control? Learning Experiences from Rural Broadband Initiatives in the Netherlands

    NARCIS (Netherlands)

    Salemink, Koen; Strijker, Dirk; Bosworth, Gary

    2017-01-01

    Based on four illustrative case studies from the Netherlands, this article discusses learning experiences gained from rural broadband initiatives. As an example of the big society' (or participatiesamenleving' in Dutch), initiatives try to step in where the market and the government fail. The main

  16. Prolonged Cerebral Circulation Time Is the Best Parameter for Predicting Vasospasm during Initial CT Perfusion in Subarachnoid Hemorrhagic Patients.

    Directory of Open Access Journals (Sweden)

    Chun Fu Lin

    Full Text Available We sought to imitate angiographic cerebral circulation time (CCT and create a similar index from baseline CT perfusion (CTP to better predict vasospasm in patients with subarachnoid hemorrhage (SAH.Forty-one SAH patients with available DSA and CTP were retrospectively included. The vasospasm group was comprised of patients with deterioration in conscious functioning and newly developed luminal narrowing; remaining cases were classified as the control group. The angiography CCT (XA-CCT was defined as the difference in TTP (time to peak between the selected arterial ROIs and the superior sagittal sinus (SSS. Four arterial ROIs were selected to generate four corresponding XA-CCTs: the right and left anterior cerebral arteries (XA-CCTRA2 and XA-CCTLA2 and right- and left-middle cerebral arteries (XA-CCTRM2 and XA-CCTLM2. The CCTs from CTP (CT-CCT were defined as the differences in TTP from the corresponding arterial ROIs and the SSS. Correlations of the different CCTs were calculated and diagnostic accuracy in predicting vasospasm was evaluated.Intra-class correlations ranged from 0.96 to 0.98. The correlations of XA-CCTRA2, XA-CCTRM2, XA-CCTLA2, and XA-CCTLM2 with the corresponding CT-CCTs were 0.64, 0.65, 0.53, and 0.68, respectively. All CCTs were significantly prolonged in the vasospasm group (5.8-6.4 s except for XA-CCTLA2. CT-CCTA2 of 5.62 was the optimal cut-off value for detecting vasospasm with a sensitivity of 84.2% and specificity 82.4.CT-CCTs can be used to interpret cerebral flow without deconvolution algorithms, and outperform both MTT and TTP in predicting vasospasm risk. This finding may help facilitate management of patients with SAH.

  17. Detection of low-grade prosthetic joint infections using 99mTc-antigranulocyte SPECT/CT: initial clinical results

    International Nuclear Information System (INIS)

    Graute, Vera; Lehner, Sebastian; Haug, Alexander; Bartenstein, Peter; Hacker, Marcus; Feist, Markus; Mueller, Peter Ernst

    2010-01-01

    Low-grade joint infections are characterized by infiltration of granulocytes, which mediate aspects of inflammatory changes. We evaluated retrospectively the contribution of SPECT/CT as an addition to planar scintigraphy with 99m Tc-labelled antigranulocyte antibodies for diagnosing and localizing low-grade joint infections. Planar scintigraphy using 99m Tc-labelled antigranulocyte BW 250/183 antibodies was performed in 31 patients with suspected joint infections at 5 min, 5 h and 24 h after injection, with additional SPECT/CT performed 6 h after injection. With reference to gold standard clinical data, we assessed the diagnostic sensitivity of scintigraphy alone and in conjunction with SPECT/CT. Joint infections were diagnosed clinically in 9 of the 31 patients (1 hip and 8 knee prostheses). Planar scintigraphy revealed 6 true-positives, 13 true-negatives, 9 false-positives and 3 false-negative results, indicating sensitivity, specificity, positive and negative predictive values of, respectively, 0.66, 0.60, 0.4 and 0.81. With the addition of SPECT images, corresponding sensitivity, specificity, positive and negative predictive values increased to 0.89, 0.45, 0.40 and 0.91. Implementation of fused SPECT/CT led to a further increase to 0.89, 0.73, 0.57 and 0.94. Relative to planar scintigraphy, SPECT with and without CT substantially improved the utility of imaging with 99m Tc-labelled antigranulocyte antibodies for diagnosis and localization of suspected joint infections. Optimal accuracy was obtained through image fusion, which permitted anatomical allocation of foci of pathological tracer accumulation as well as providing information on the extent of the infection. This imaging method seems suited for selection of patients requiring surgical therapy. (orig.)

  18. CT features of peritoneal and mesenteric involvement in pediatric malignancies. Experience from thirteen cases

    International Nuclear Information System (INIS)

    Grenier, N.; Filiatrault, D.; Garel, L.; Dube, J.; Paille, P.; Grenier, N.

    1986-01-01

    A retrospective study of all patients presenting with abdominal malignancies since November 1982 was undertaken in order to assess the CT features of peritoneal and mesenteric involvement in childhood. Thirteen cases, including 4 cases of malignant lymphomas, 1 case of Hodgkin's disease, 5 cases of adrenal tumors and 3 cases of ovarian tumors, were selected. Providing a good technique, CT appears as the best imaging modality of the mesentery. CT is also reliable in showing peritoneal implants, even without ascites. A high quality vascular opacification is needed in order to recognize the involvement of the lesser omentum (6/13 cases in our series). Precise knowledge of the intra-abdominal extension of the primary neoplasm has a definite impact upon the surgical indications and therefore upon the prognosis [fr

  19. Clinical experience with a commercially available negative oral contrast medium in PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Hausegger, K.; Reinprecht, P. [Roentgendiagnostisches Zentralinstitut, LKH Klagenfurt (Austria); Kau, T. [Roentgendiagnostisches Zentral Inst., Klagenfurt (Austria); Igerc, I.; Lind, P. [Abt. fuer Nuklearmedizin und Spezielle Endokrinologie, LKH Klagenfurt (Austria)

    2005-06-01

    Purpose: to evaluate a commercially available negative oral contrast material for PET/CT. Material and methods: in a prospective series of 49 patients, Mukofalk {sup registered}, which is a vegetarian-based substance, was used as a negative oral contrast medium in whole body PET/CT studies. Mukofalk was administered during a time period of 1.5 hours before the examination. Quality of small bowl distension and eventual pathological tracer uptake in the intestine were evaluated. Results: distension of the small bowel was excellent or good in 41 (85%) and poor in 8 (15%) patients. Mild tracer uptake in the small bowel was observed in 5 patients (10.2%) and moderate uptake in another 2 patients (4%). In none of these patients did the F-18 FDG uptake interfere with image interpretation. Conclusion: Mukofalk {sup registered} can be used as a negative oral contrast medium in PET/CT studies. (orig.)

  20. Clinical experience with a commercially available negative oral contrast medium in PET/CT

    International Nuclear Information System (INIS)

    Hausegger, K.; Reinprecht, P.; Kau, T.; Igerc, I.; Lind, P.

    2005-01-01

    Purpose: to evaluate a commercially available negative oral contrast material for PET/CT. Material and methods: in a prospective series of 49 patients, Mukofalk registered , which is a vegetarian-based substance, was used as a negative oral contrast medium in whole body PET/CT studies. Mukofalk was administered during a time period of 1.5 hours before the examination. Quality of small bowl distension and eventual pathological tracer uptake in the intestine were evaluated. Results: distension of the small bowel was excellent or good in 41 (85%) and poor in 8 (15%) patients. Mild tracer uptake in the small bowel was observed in 5 patients (10.2%) and moderate uptake in another 2 patients (4%). In none of these patients did the F-18 FDG uptake interfere with image interpretation. Conclusion: Mukofalk registered can be used as a negative oral contrast medium in PET/CT studies. (orig.)

  1. 18F-DOPA PET/CT Physiological Distribution and Pitfalls: Experience in 215 Patients.

    Science.gov (United States)

    Calabria, Ferdinando F; Chiaravalloti, Agostino; Jaffrain-Rea, Marielise L; Zinzi, Maddalena; Sannino, Pasqualina; Minniti, Giuseppe; Rubello, Domenico; Schillaci, Orazio

    2016-10-01

    F-DOPA PET/CT is potentially helpful in the management of patients with low-grade brain tumors, movement disorders, and somatic neuroendocrine tumors. We describe the whole-body physiological distribution of F-DOPA uptake. We examined 215 patients with F-DOPA PET/CT. Among these, 161 had brain scans and 54 had whole-body scans. Physiological distribution was negligible in the brain, with the exception of basal ganglia, whereas greatest activity was noted in the liver, pancreas, other exocrine glands, and the urinary system. Incidental tracer uptake sites were identified in 5.5% of patients. Some of these findings were due to inflammation, whereas in most cases, uptake was seen in benign tumors of the brain or in the endocrine or exocrine glands. F-DOPA uptake may be seen in inflammatory tissue or benign tumors. Correlations with history, physical examination, laboratory examination, CT, MRI, and histology are necessary for optimal diagnosis.

  2. CT-guided biopsy with cutting-edge needle for the diagnosis of malignant lymphoma: Experience of 267 biopsies

    International Nuclear Information System (INIS)

    Agid, R.; Sklair-Levy, M.; Bloom, A.I.; Lieberman, S.; Polliack, A.; Ben-Yehuda, D.; Sherman, Y.; Libson, E.

    2003-01-01

    AIM: We performed a retrospective study of 267 core needle aspiration biopsies in order to estimate the accuracy of CT-guided aspiration core needle biopsies for the diagnosis and subsequent treatment of malignant lymphoma. MATERIALS AND METHODS: Between 1989 and 1999, 267 CT-guided core needle biopsies were performed in 241 patients with either primary or recurrent malignant lymphoma. Patients age ranged from 4--88 years. One hundred and sixty-six (62.2%) nodal and 101 (37.8%) extranodal aspiration biopsies were performed using either 18 G or 20 G Turner needles. Statistical method used was Chi-square analysis. RESULTS: An accurate histological diagnosis was made in 199 (82.5%) patients, the remaining 42 (17.4%) patients had non-diagnostic CT biopsies. Thirty-seven of them were diagnosed by a surgical biopsy, four by bone marrow biopsy and in one patient by paracentesis. One hundred and seventy-nine patients had non-Hodgkin's lymphoma (NHL) and 62 had Hodgkin's disease (HD); 23 (9.54%) patients underwent repeated CT biopsy which was diagnostic in 17 (73.9%) and non-diagnostic in six (26%). CONCLUSION: CT-guided aspiration core biopsies were sufficient to establish a diagnosis in lymphoproliferative disorders in 82.5% of cases. In the light of this experience we suggest that imaging-guided core needle biopsy be used as the first step in the work up of many patients with lymphoma Agid,R. et al. (2003). Clinical Radiology58, 143-147

  3. Water sector fund (CT-hi dro) and wastewater reuse activities: initiatives to promote environment ally sustainable development in Brazil

    International Nuclear Information System (INIS)

    Leitao, S.A.M.

    2005-01-01

    The Brazilian Water Sector Fund (CT-Hidro) is presented as an innovative mechanism to foster the scientific and technological sector of the country as well as a model instrument to promote environmentally sustainable development in Brazil and in other developing countries. CT-Hidro is shown as an instrument that provides support for scientific and technological development research activities in the following areas: experimental technological development, scientific and technological research projects, development of basic industrial technology and implantation of research infrastructure. CT-Hidro is presented as a key mechanism to finance wastewater reuse projects as an imperative action to fight poverty and promote social inclusion in Brazil. The concept of wastewater reuse for beneficial purposes is presented. Its growing importance as an essential part of the planning of the integrated and sustainable water resources management is also evidenced. In this perspective, the need for sanitation, wastewater treatment and its reuse in agriculture for food production are presented as imperative measures that must be taken in Brazil in order to promote sustainable development, fight poverty, improve public health conditions and enhance environmental quality in the country. (author)

  4. First experiences of application of computer tomography (CT) in pediatric neurology

    International Nuclear Information System (INIS)

    Nagy, I.; Deak, Gy.; Paraicz, E.

    1980-01-01

    79 children were examined by the first Hungarian CT equipment (Medicor-CGR Densitome connected to a PDP 11/55 computer). The advantages of the method in the diagnosis of malformations, perinatal injuries, hydrocephalus, skull injuries and cerebral tumours are demonstrated. The problems arising from the application of instruments requiring long examination time are discussed. (L.E.)

  5. First experience with multidetector-CT for the diagnosis of coronary atherosclerosis

    International Nuclear Information System (INIS)

    Becker, C.R.; Hong, C.; Schoepf, U.J.; Reiser, M.F.; Knez, A.; Leber, A.; Treede, H.; Wildhirt, S.; Ohnesorge, B.; Flohr, T.

    2000-01-01

    Purpose: Multirow-detector-spiral-CT (MSCT) allows for 250 ms effective exposure time. The purpose of this study was to demonstrate the possibilities and limitations of this CT technology for non enhanced and contrast enhanced investigation of the coronary arteries. Methods: Investigation of the coronary arteries without contrast medium for quantification of coronary calcifications was performed in an obese patient (140 kg) with MSCT and electron beam CT (EBCT). In 56 patients contrast enhanced CT angiography of the coronary arteries was performed to determine image quality depending on the heart rate. Results: In the obese patient superior image quality could be achieved with MSCT allowing for reliable quantification of coronary calcifications. With MSCT angiography of the coronary arteries good image quality was achieved in patients with a heart rate of 59±8 beats per minute. Conclusion: Even if there are limitations in patients with higher heart rates with an effective exposure time of 250 ms MSCT has clear advantage of image quality in the assessment of non enhanced and contrast enhanced coronary arteries. (orig.) [de

  6. First experiences of application of computer tomography (CT) in pediatric neurology

    Energy Technology Data Exchange (ETDEWEB)

    Nagy, I; Deak, Gy; Paraicz, E [Orszagos Idegsebeszeti Tudomanyos Intezet, Budapest (Hungary)

    1980-01-01

    79 children were examined by the first Hungarian CT equipment (Medicor-CGR Densitome connected to a PDP 11/55 computer). The advantages of the method in the diagnosis of malformations, perinatal injuries, hydrocephalus, skull injuries and cerebral tumours are demonstrated. The problems arising from the application of instruments requiring long examination time are discussed.

  7. Experience of CT Guided Procedures in the Diagnosis of 55 patients ...

    African Journals Online (AJOL)

    All fine needle aspirations were performed with 20-gauge needles while core tissue biopsies were performed with 14 –gauge needles under CT guidance. The diagnostic yield of these procedures, complications, and patient's feedback were studied. Results: Diagnosis was malignant lesions in 18(32.1%), benign in ...

  8. Lung cancer screening with low-dose helical CT in Korea: experiences at the Samsung Medical Center.

    Science.gov (United States)

    Chong, Semin; Lee, Kyung Soo; Chung, Myung Jin; Kim, Tae Sung; Kim, Hojoong; Kwon, O Jung; Choi, Yoon-Ho; Rhee, Chong H

    2005-06-01

    To determine overall detection rates of lung cancer by low-dose CT (LDCT) screening and to compare histopathologic and imaging differences of detected cancers between high- and low-risk groups, this study included 6,406 asymptomatic Korean adults with >or=45 yr of age who underwent LDCT for lung cancer screening. All were classified into high- (>or=20 pack-year smoking; 3,353) and low-risk (3,053; <20 pack-yr smoking and non-smokers) groups. We compared CT findings of detected cancers and detection rates between high- and low-risk. At initial CT, 35% (2,255 of 6,406) had at least one or more non-calcified nodule. Lung cancer detection rates were 0.36% (23 of 6,406). Twenty-one non-small cell lung cancers appeared as solid (n=14) or ground-glass opacity (GGO) (n=7) nodules. Cancer likelihood was higher in GGO nodules than in solid nodules (p<0.01). Fifteen of 23 cancers occurred in high-risk group and 8 in low-risk group (p=0.215). Therefore, LDCT screening help detect early stage of lung cancer in asymptomatic Korean population with detection rate of 0.36% on a population basis and may be useful for discovering early lung cancer in low-risk group as well as in high-risk group.

  9. Intraarterial CT Angiography Using Ultra Low Volume of Iodine Contrast – Own Experiences

    International Nuclear Information System (INIS)

    Garcarek, Jerzy; Kurcz, Jacek; Guziński, Maciej; Banasik, Mirosław; Miś, Marcin; Gołębiowski, Tomasz

    2015-01-01

    High volume of intravenous contrast in CT-angiography may result in contrast-induced nephropathy. Intraarterial ultra-low volume of contrast medium results in its satisfactory blood concentration with potentially good image quality. The first main purpose was to assess the influence of the method on function of transplanted kidney in patients with impaired graft function. The second main purpose of the study was to evaluate the usefulness of this method for detection of gastrointestinal and head-and-neck haemorrhages. Between 2010 and 2013 intraarterial CT-angiography was performed in 56 patients, including 28 with chronic kidney disease (CKD). There were three main subgroups: 18 patients after kidney transplantation, 10 patients with gastrointestinal hemorrhage, 8 patients with head-and-neck hemorrhage. Contralateral or ipsilateral inguinal arterial approach was performed. The 4-French vascular sheaths and 4F-catheters were introduced under fluoroscopy. Intraarterial CT was performed using 64-slice scanner. The scanning protocol was as follows: slice thickness 0.625 mm, pitch 1.3, gantry rotation 0.6 sec., scanning delay 1–2 sec. The extent of the study was established on the basis of scout image. In patients with CKD 6–8 mL of Iodixanol (320 mg/mL) diluted with saline to 18–24 mL was administered at a speed of 4–5 mL/s. Vasculature was properly visualized in all patients. In patients with impaired renal function creatinine/eGFR levels remained stable in all but one case. Traditional arteriography failed and CT-angiography demonstrated the site of bleeding in 3 of 10 patients with symptoms of gastrointestinal bleeding (30%). In 8 patients with head-and-neck bleeding CT-angiography did not prove beneficial when compared to traditional arteriography. 1. Ultra-low contrast intraarterial CT-angiography does not deteriorate the function of transplanted kidneys in patients with impaired graft function. 2. 3D reconstructions allow for excellent visualization of

  10. Respiratory management of CT-transmission for accuracy fusion in PET/CT. A comparison between normal expiration and free breathing in 600 experiences

    International Nuclear Information System (INIS)

    Osawa, Atsushi; Takiguchi, Tomohiro; Tamura, Shintaro; Ohashi, Takashi; Miwa, Kenta; Akimoto, Kenta; Wagatsuma, Kei

    2010-01-01

    Image misregistration can occur in fusion positron emission tomography (PET)/CT, because of motion artifacts caused by the management of respiration. The standard imaging protocol of the CT component of PET/CT is normal expiration (NormExp) or free breathing (FB). The objective of this study was to compare NormExp and FB for the optimal breathing protocol for PET/CT scans. A total of 600 consecutive patients were examined using lutetium oxyorthosilicate (LSO)-based PET/CT. CT was acquired during NormExp (id est (i.e.), the level reached when the patient exhaled without forcing expiration and then held the breath) in 300 patients and during FB in 300 patients. The profile of liver measured along body axis was assessed. The distance of profile centers between the PET image and the CT image was measured. The misalignment between profile centers (PET) and profile centers (CT) was compared between NormExp and FB using the histogram of patients. An F test was used to test if the variances of two misalignments are equal. Next, the relationship between misalignment and age was evaluated in two managements of respiration. There was no significant difference between NormExp and FB in the histogram. However, significant misalignments (>10 cm) were found with NormExp. Patient age may have influenced the mismatch. FB is recommended for geriatric patients during acquisition of attenuation correction CT data sets. (author)

  11. Flat panel computed tomography of human ex vivo heart and bone specimens: initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Nikolaou, Konstantin; Becker, Christoph R.; Reiser, Maximilian F. [Ludwig-Maximilians-University, Department of Clinical Radiology, Munich (Germany); Flohr, Thomas; Stierstorfer, Karl [CT Division, Siemens Medical Solutions, Forchheim (Germany)

    2005-02-01

    The aim of this technical investigation was the detailed description of a prototype flat panel detector computed tomography system (FPCT) and its initial evaluation in an ex vivo setting. The prototype FPCT scanner consists of a conventional radiographic flat panel detector, mounted on a multi-slice CT scanner gantry. Explanted human ex vivo heart and foot specimens were examined. Images were reformatted with various reconstruction algorithms and were evaluated for high-resolution anatomic information. For comparison purposes, the ex vivo specimens were also scanned with a conventional 16-detector-row CT scanner (Sensation 16, Siemens Medical Solutions, Forchheim, Germany). With the FPCT prototype used, a 1,024 x 768 resolution matrix can be obtained, resulting in an isotropic voxel size of 0.25 x 0.25 x 0.25 mm at the iso-center. Due to the high spatial resolution, very small structures such as trabecular bone or third-degree, distal branches of coronary arteries could be visualized. This first evaluation showed that flat panel detector systems can be used in a cone-beam computed tomography scanner and that very high spatial resolutions can be achieved. However, there are limitations for in vivo use due to constraints in low contrast resolution and slow scan speed. (orig.)

  12. Plans for longitudinal and transverse neutralized beam compression experiments, and initial results from solenoid transport experiments

    International Nuclear Information System (INIS)

    Seidl, P.A.; Armijo, J.; Baca, D.; Bieniosek, F.M.; Coleman, J.; Davidson, R.C.; Efthimion, P.C.; Friedman, A.; Gilson, E.P.; Grote, D.; Haber, I.; Henestroza, E.; Kaganovich, I.; Leitner, M.; Logan, B.G.; Molvik, A.W.; Rose, D.V.; Roy, P.K.; Sefkow, A.B.; Sharp, W.M.; Vay, J.L.; Waldron, W.L.; Welch, D.R.; Yu, S.S.

    2007-01-01

    This paper presents plans for neutralized drift compression experiments, precursors to future target heating experiments. The target-physics objective is to study warm dense matter (WDM) using short-duration (∼1 ns) ion beams that enter the targets at energies just above that at which dE/dx is maximal. High intensity on target is to be achieved by a combination of longitudinal compression and transverse focusing. This work will build upon recent success in longitudinal compression, where the ion beam was compressed lengthwise by a factor of more than 50 by first applying a linear head-to-tail velocity tilt to the beam, and then allowing the beam to drift through a dense, neutralizing background plasma. Studies on a novel pulse line ion accelerator were also carried out. It is planned to demonstrate simultaneous transverse focusing and longitudinal compression in a series of future experiments, thereby achieving conditions suitable for future WDM target experiments. Future experiments may use solenoids for transverse focusing of un-neutralized ion beams during acceleration. Recent results are reported in the transport of a high-perveance heavy ion beam in a solenoid transport channel. The principal objectives of this solenoid transport experiment are to match and transport a space-charge-dominated ion beam, and to study associated electron-cloud and gas effects that may limit the beam quality in a solenoid transport system. Ideally, the beam will establish a Brillouin-flow condition (rotation at one-half the cyclotron frequency). Other mechanisms that potentially degrade beam quality are being studied, such as focusing-field aberrations, beam halo, and separation of lattice focusing elements

  13. Consideration of the Intracranial Pressure Threshold Value for the Initiation of Traumatic Brain Injury Treatment: A Xenon CT and Perfusion CT Study.

    Science.gov (United States)

    Honda, Mitsuru; Ichibayashi, Ryo; Suzuki, Ginga; Yokomuro, Hiroki; Seiki, Yoshikatsu; Sase, Shigeru; Kishi, Taichi

    2017-12-01

    Monitoring of intracranial pressure (ICP) is considered to be fundamental for the care of patients with severe traumatic brain injury (TBI) and is routinely used to direct medical and surgical therapy. Accordingly, some guidelines for the management of severe TBI recommend that treatment be initiated for ICP values >20 mmHg. However, it remained to be accounted whether there is a scientific basis to this instruction. The purpose of the present study was to clarify whether the basis of ICP values >20 mmHg is appropriate. We retrospectively reviewed 25 patients with severe TBI who underwent neuroimaging during ICP monitoring within the first 7 days. We measured cerebral blood flow (CBF), mean transit time (MTT), cerebral blood volume (CBV), and ICP 71 times within the first 7 days. Although the CBF, MTT, and CBV values were not correlated with the ICP value at ICP values ≤20 mmHg, the CBF value was significantly negatively correlated with the ICP value (r = -0.381, P values >20 mmHg. The MTT value was also significantly positively correlated with the ICP value (r = 0.638, P values >20 mmHg. The cerebral circulation disturbance increased with the ICP value. We demonstrated the cerebral circulation disturbance at ICP values >20 mmHg. This study suggests that an ICP >20 mmHg is the threshold to initiate treatments. An active treatment intervention would be required for severe TBI when the ICP was >20 mmHg.

  14. Nondestructive test for assembly relationship of initiating explosive device

    International Nuclear Information System (INIS)

    Wang Xiangang; Zhang Chaozong; Guo Zhiping

    2009-01-01

    A 3D computed tomography (CT) method to inspect assembly relationship of initiating explosive device and to nondestructively evaluate assembly relationship by building geometric model from CT images was described. The experiment result proves that this method accurately inspects assembly relationship of initiating explosive device. (authors)

  15. Pulmonary Masses: Initial Results of Cone-beam CT Guidance with Needle Planning Software for Percutaneous Lung Biopsy

    Energy Technology Data Exchange (ETDEWEB)

    Braak, Sicco J., E-mail: sjbraak@gmail.com [St. Antonius Hospital, Department of Radiology (Netherlands); Herder, Gerarda J. M., E-mail: j.herder@antoniusziekenhuis.nl [St. Antonius Hospital, Department of Pulmonology (Netherlands); Heesewijk, Johannes P. M. van, E-mail: j.heesewijk@antoniusziekenhuis.nl; Strijen, Marco J. L. van, E-mail: m.van.strijen@antoniusziekenhuis.nl [St. Antonius Hospital, Department of Radiology (Netherlands)

    2012-12-15

    Purpose: To evaluate the outcome of percutaneous lung biopsy (PLB) findings using cone-beam computed tomographic (CT) guidance (CBCT guidance) and compared to conventional biopsy guidance techniques. Methods: CBCT guidance is a stereotactic technique for needle interventions, combining 3D soft-tissue cone-beam CT, needle planning software, and real-time fluoroscopy. Between March 2007 and August 2010, we performed 84 Tru-Cut PLBs, where bronchoscopy did not provide histopathologic diagnosis. Mean patient age was 64.6 (range 24-85) years; 57 patients were men, and 25 were women. Records were prospectively collected for calculating sensitivity, specificity, positive predictive value, negative predictive value, and accuracy. We also registered fluoroscopy time, room time, interventional time, dose-area product (DAP), and complications. Procedures were divided into subgroups (e.g., location, size, operator). Results: Mean lesion diameter was 32.5 (range 3.0-93.0) mm, and the mean number of samples per biopsy procedure was 3.2 (range 1-7). Mean fluoroscopy time was 161 (range 104-551) s, room time was 34 (range 15-79) min, mean DAP value was 25.9 (range 3.9-80.5) Gy{center_dot}cm{sup -2}, and interventional time was 18 (range 5-65) min. Of 84 lesions, 70 were malignant (83.3%) and 14 were benign (16.7%). Seven (8.3%) of the biopsy samples were nondiagnostic. All nondiagnostic biopsied lesions proved to be malignant during surgical resection. The outcome for sensitivity, specificity, positive predictive value, negative predictive value, and accuracy was 90% (95% confidence interval [CI] 86-96), 100% (95% CI 82-100), 100% (95% CI 96-100), 66.7% (95% CI 55-83), and 91.7% (95% CI 86-96), respectively. Sixteen patients (19%) had minor and 2 (2.4%) had major complications. Conclusion: CBCT guidance is an effective method for PLB, with results comparable to CT/CT fluoroscopy guidance.

  16. Quantitative assessment of left ventricular function with dual-source CT in comparison to cardiac magnetic resonance imaging: initial findings

    Energy Technology Data Exchange (ETDEWEB)

    Busch, S.; Johnson, T.R.C.; Wintersperger, B.J.; Minaifar, N.; Bhargava, A.; Rist, C.; Reiser, M.F.; Becker, C.; Nikolaou, K. [University of Munich, Department of Clinical Radiology, Munich (Germany)

    2008-03-15

    Cardiac magnetic resonance imaging and echocardiography are currently regarded as standard modalities for the quantification of left ventricular volumes and ejection fraction. With the recent introduction of dual-source computedtomography (DSCT), the increased temporal resolution of 83 ms should also improve the assessment of cardiac function in CT. The aim of this study was to evaluate the accuracy of DSCT in the assessment of left ventricular functional parameters with cardiac magnetic resonance imaging (MRI) as standard of reference. Fifteen patients (two female, 13 male; mean age 50.8 {+-} 19.2 years) underwent CT and MRI examinations on a DSCT (Somatom Definition; Siemens Medical Solutions, Forchheim, Germany) and a 3.0-Tesla MR scanner (Magnetom Trio; Siemens Medical Solutions), respectively. Multiphase axial CT images were analysed with a semiautomatic region growing algorithms (Syngo Circulation; Siemens Medical Solutions) by two independent blinded observers. In MRI, dynamic cine loops of short axis slices were evaluated with semiautomatic contour detection software (ARGUS; Siemens Medical Solutions) independently by two readers. End-systolic volume (ESV), end-diastolic volume (EDV), ejection fraction (EF) and stroke volume (SV) were determined for both modalities, and correlation coefficient, systematic error, limits of agreement and inter-observer variability were assessed. In DSCT, EDV and ESV were 135.8 {+-} 41.9 ml and 54.9 {+-} 29.6 ml, respectively, compared with 132.1 {+-} 40.8 ml EDV and 57.6 {+-} 27.3 ml ESV in MRI. Thus, EDV was overestimated by 3.7 ml (limits of agreement -46.1/+53.6), while ESV was underestimated by 2.6 ml (-36.6/+31.4). Mean EF was 61.6 {+-} 12.4% in DSCT and 57.9 {+-} 9.0% in MRI, resulting in an overestimation of EF by 3.8% with limits of agreement at -14.7 and +22.2%. Rank correlation rho values were 0.81 for EDV (P = 0.0024), 0.79 for ESV (P = 0.0031) and 0.64 for EF (P = 0.0168). The kappa value of inter

  17. Metastasis in the base of the cranium: initial manifestation of a hepato carcinoma. Findings in the CT and MRI

    International Nuclear Information System (INIS)

    Fernandez, M. T.; Saiz, A.; Cardenal, A.; Oruezabal, M.

    2000-01-01

    We present a case of hepato carcinoma (HC) whose first clinical manifestation was diplopia. The imaging methods showed a sold mass in the base of the cranium with meningioma characteristics. The histological study showed the existence of hepatocytes, which confirmed the diagnosis of metastasis of the HC: We present the X-ray findings in the CT and MRI of this case and the differential diagnosis with other tumors that affect the cranium base. We also perform a bibliographic review of this clinical manifestation with such an unusual X-ray. (Author) 19 refs

  18. Pulmonary Masses: Initial Results of Cone-beam CT Guidance with Needle Planning Software for Percutaneous Lung Biopsy

    International Nuclear Information System (INIS)

    Braak, Sicco J.; Herder, Gerarda J. M.; Heesewijk, Johannes P. M. van; Strijen, Marco J. L. van

    2012-01-01

    Purpose: To evaluate the outcome of percutaneous lung biopsy (PLB) findings using cone-beam computed tomographic (CT) guidance (CBCT guidance) and compared to conventional biopsy guidance techniques. Methods: CBCT guidance is a stereotactic technique for needle interventions, combining 3D soft-tissue cone-beam CT, needle planning software, and real-time fluoroscopy. Between March 2007 and August 2010, we performed 84 Tru-Cut PLBs, where bronchoscopy did not provide histopathologic diagnosis. Mean patient age was 64.6 (range 24–85) years; 57 patients were men, and 25 were women. Records were prospectively collected for calculating sensitivity, specificity, positive predictive value, negative predictive value, and accuracy. We also registered fluoroscopy time, room time, interventional time, dose–area product (DAP), and complications. Procedures were divided into subgroups (e.g., location, size, operator). Results: Mean lesion diameter was 32.5 (range 3.0–93.0) mm, and the mean number of samples per biopsy procedure was 3.2 (range 1–7). Mean fluoroscopy time was 161 (range 104–551) s, room time was 34 (range 15–79) min, mean DAP value was 25.9 (range 3.9–80.5) Gy·cm −2 , and interventional time was 18 (range 5–65) min. Of 84 lesions, 70 were malignant (83.3%) and 14 were benign (16.7%). Seven (8.3%) of the biopsy samples were nondiagnostic. All nondiagnostic biopsied lesions proved to be malignant during surgical resection. The outcome for sensitivity, specificity, positive predictive value, negative predictive value, and accuracy was 90% (95% confidence interval [CI] 86–96), 100% (95% CI 82–100), 100% (95% CI 96–100), 66.7% (95% CI 55–83), and 91.7% (95% CI 86–96), respectively. Sixteen patients (19%) had minor and 2 (2.4%) had major complications. Conclusion: CBCT guidance is an effective method for PLB, with results comparable to CT/CT fluoroscopy guidance.

  19. Quantitative assessment of left ventricular function with dual-source CT in comparison to cardiac magnetic resonance imaging: initial findings

    International Nuclear Information System (INIS)

    Busch, S.; Johnson, T.R.C.; Wintersperger, B.J.; Minaifar, N.; Bhargava, A.; Rist, C.; Reiser, M.F.; Becker, C.; Nikolaou, K.

    2008-01-01

    Cardiac magnetic resonance imaging and echocardiography are currently regarded as standard modalities for the quantification of left ventricular volumes and ejection fraction. With the recent introduction of dual-source computedtomography (DSCT), the increased temporal resolution of 83 ms should also improve the assessment of cardiac function in CT. The aim of this study was to evaluate the accuracy of DSCT in the assessment of left ventricular functional parameters with cardiac magnetic resonance imaging (MRI) as standard of reference. Fifteen patients (two female, 13 male; mean age 50.8 ± 19.2 years) underwent CT and MRI examinations on a DSCT (Somatom Definition; Siemens Medical Solutions, Forchheim, Germany) and a 3.0-Tesla MR scanner (Magnetom Trio; Siemens Medical Solutions), respectively. Multiphase axial CT images were analysed with a semiautomatic region growing algorithms (Syngo Circulation; Siemens Medical Solutions) by two independent blinded observers. In MRI, dynamic cine loops of short axis slices were evaluated with semiautomatic contour detection software (ARGUS; Siemens Medical Solutions) independently by two readers. End-systolic volume (ESV), end-diastolic volume (EDV), ejection fraction (EF) and stroke volume (SV) were determined for both modalities, and correlation coefficient, systematic error, limits of agreement and inter-observer variability were assessed. In DSCT, EDV and ESV were 135.8 ± 41.9 ml and 54.9 ± 29.6 ml, respectively, compared with 132.1 ± 40.8 ml EDV and 57.6 ± 27.3 ml ESV in MRI. Thus, EDV was overestimated by 3.7 ml (limits of agreement -46.1/+53.6), while ESV was underestimated by 2.6 ml (-36.6/+31.4). Mean EF was 61.6 ± 12.4% in DSCT and 57.9 ± 9.0% in MRI, resulting in an overestimation of EF by 3.8% with limits of agreement at -14.7 and +22.2%. Rank correlation rho values were 0.81 for EDV (P = 0.0024), 0.79 for ESV (P 0.0031) and 0.64 for EF (P = 0.0168). The kappa value of inter-observer variability were

  20. An experience of detection brain disease by roentgenographic CT on head

    International Nuclear Information System (INIS)

    Kobata, Daikichi

    1996-01-01

    MRI and MRA are recommended today from the standpoint of sensitivity for the detraction of asymptomatic brain disease, and roentgenographic CT on head is not recommended. Under certain circumstances, however, having recently been given an opportunity of detecting brain disease by means of roentgenographic CT on head, we make a report of the diagnostic results. The examinees were the staff members of a non-profit organization consisting of 62 men and 56 women whose age was 48.6 years on the average. Asymptomatic brain disease was found in 6 cases including 1 case of cerebral infarction, 1 case of calcification of cerebral vascular wall and 1 case of cranial osteoma with a suspicion of Gardner syndrome. Incidentally, there were 31 cases with a complaint of headache, 20 cases of hypertension and 3 cases with a past history of head trauma. After such findings were obtained, guidance was provided to each of them. (author)

  1. The Lung Image Database Consortium (LIDC) and Image Database Resource Initiative (IDRI): A Completed Reference Database of Lung Nodules on CT Scans

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-02-15

    Purpose: The development of computer-aided diagnostic (CAD) methods for lung nodule detection, classification, and quantitative assessment can be facilitated through a well-characterized repository of computed tomography (CT) scans. The Lung Image Database Consortium (LIDC) and Image Database Resource Initiative (IDRI) completed such a database, establishing a publicly available reference for the medical imaging research community. Initiated by the National Cancer Institute (NCI), further advanced by the Foundation for the National Institutes of Health (FNIH), and accompanied by the Food and Drug Administration (FDA) through active participation, this public-private partnership demonstrates the success of a consortium founded on a consensus-based process. Methods: Seven academic centers and eight medical imaging companies collaborated to identify, address, and resolve challenging organizational, technical, and clinical issues to provide a solid foundation for a robust database. The LIDC/IDRI Database contains 1018 cases, each of which includes images from a clinical thoracic CT scan and an associated XML file that records the results of a two-phase image annotation process performed by four experienced thoracic radiologists. In the initial blinded-read phase, each radiologist independently reviewed each CT scan and marked lesions belonging to one of three categories (''nodule{>=}3 mm,''''nodule<3 mm,'' and ''non-nodule{>=}3 mm''). In the subsequent unblinded-read phase, each radiologist independently reviewed their own marks along with the anonymized marks of the three other radiologists to render a final opinion. The goal of this process was to identify as completely as possible all lung nodules in each CT scan without requiring forced consensus. Results: The Database contains 7371 lesions marked ''nodule'' by at least one radiologist. 2669 of these lesions were marked &apos

  2. The Lung Image Database Consortium (LIDC) and Image Database Resource Initiative (IDRI): A Completed Reference Database of Lung Nodules on CT Scans

    International Nuclear Information System (INIS)

    2011-01-01

    Purpose: The development of computer-aided diagnostic (CAD) methods for lung nodule detection, classification, and quantitative assessment can be facilitated through a well-characterized repository of computed tomography (CT) scans. The Lung Image Database Consortium (LIDC) and Image Database Resource Initiative (IDRI) completed such a database, establishing a publicly available reference for the medical imaging research community. Initiated by the National Cancer Institute (NCI), further advanced by the Foundation for the National Institutes of Health (FNIH), and accompanied by the Food and Drug Administration (FDA) through active participation, this public-private partnership demonstrates the success of a consortium founded on a consensus-based process. Methods: Seven academic centers and eight medical imaging companies collaborated to identify, address, and resolve challenging organizational, technical, and clinical issues to provide a solid foundation for a robust database. The LIDC/IDRI Database contains 1018 cases, each of which includes images from a clinical thoracic CT scan and an associated XML file that records the results of a two-phase image annotation process performed by four experienced thoracic radiologists. In the initial blinded-read phase, each radiologist independently reviewed each CT scan and marked lesions belonging to one of three categories (''nodule≥3 mm,''''nodule<3 mm,'' and ''non-nodule≥3 mm''). In the subsequent unblinded-read phase, each radiologist independently reviewed their own marks along with the anonymized marks of the three other radiologists to render a final opinion. The goal of this process was to identify as completely as possible all lung nodules in each CT scan without requiring forced consensus. Results: The Database contains 7371 lesions marked ''nodule'' by at least one radiologist. 2669 of these lesions were marked ''nodule≥3 mm'' by at least one radiologist, of which 928 (34.7%) received such marks from all

  3. CT and MR imaging acquisition performance in a neuroradiology PACS module 1-year clinical experience

    International Nuclear Information System (INIS)

    Lou, S.L.; Loloyan, M.; Weinberg, W.S.; Valentino, D.J.; Lufkin, R.B.; Hanafee, W.N.; Bentson, J.; Jabour, B.A.; Huang, H.K.

    1990-01-01

    This paper analyzes the operational efficiency of our neuroradiology PACS compared with conventional film-based management systems. The authors neuroradiology PACS module has been in clinical evaluation for 6 months. Three SUN microcomputers, two PC/ATs, and an automated optical disk library are connected through Ethernet. Software implemented at the TCP/IP level is used to transfer images from MR imagers and CT scanners to a viewing station. Performance measurements include the time elapsed at each stage of the system

  4. Spectral CT evaluation of interstitial brachytherapy in pancreatic carcinoma xenografts: preliminary animal experience

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Shudong [Jiangsu University, Department of Radiology, The Affiliated Renmin Hospital, Zhenjiang, Jiangsu (China); Shanghai Jiao tong University, School of Medicine, Department of Radiology, Ruijin Hospital, Shanghai (China); Huang, Wei; Song, Qi; Lin, Xiaozhu; Wang, Zhongmin; Chen, Kemin [Shanghai Jiao tong University, School of Medicine, Department of Radiology, Ruijin Hospital, Shanghai (China); Chen, Yerong [Jiangsu University, Department of Radiology, The Affiliated Renmin Hospital, Zhenjiang, Jiangsu (China)

    2014-09-15

    We sought to evaluate the capability of spectral CT to detect the therapeutic response to {sup 125}I interstitial brachytherapy in a pancreatic carcinoma xenograft nude mouse model. Twenty mice bearing SWl990 human pancreatic cancer cell xenografts were randomly separated into two groups: experimental (n = 10; 1.0 mCi) and control (n = 10; 0 mCi). After a two-week treatment, spectral CT was performed. Contrast-to-noise ratio (CNR) and iodine concentration (IC) in the lesions were measured and normalized to the muscle tissue, and nIC CD31 immunohistochemistry was used to measure microvessel density (MVD). The relationships between the nIC and MVD of the tumours were analysed. The nIC of the experimental group was significantly lower than that of the control group during the multiphase examination. A significant difference in the MVD was observed between the two groups (P <0.001). The nIC values of the three-phase scans have a certain positive correlation with MVD (r = 0.57, p < 0.0001; r = 0.48, p = 0.002; r = 0.63, p = 0.0017 in the 10, 25, and 60 s phase, respectively). Spectral CT can be a useful non-invasive imaging modality in evaluating the therapeutic effect of {sup 125}I interstitial brachytherapy to a pancreatic carcinoma. (orig.)

  5. African American women's experiences with the initial discovery, diagnosis, and treatment of breast cancer.

    Science.gov (United States)

    Lackey, N R; Gates, M F; Brown, G

    2001-04-01

    To describe the experiences of African American women living with breast cancer following the primary diagnosis and while undergoing initial treatment. Phenomenologic. 13 African American women (ages 30-66) purposefully selected from two oncology clinics in the mid-South. Phenomenologic interviews (transcribed verbatim) and field notes were analyzed using Colaizzi's method of phenomenologic description and analysis. Experience Trajectory, Femininity, and Spirituality were the three major themes. The Experience Trajectory subthemes were finding the lump, getting the diagnosis, undergoing surgery and adjuvant treatment. The Femininity subthemes were loss of all or part of the breast, loss of hair, and sexual attractiveness to a man. Spirituality was reflected as a reliance on God. Telling the story of their experience trajectory during their breast cancer experience is valuable in assessing African American women's feelings, emotions, and fears of body changes that occur during surgery and treatment. Their spirituality helps them through this experience. Research involving both African American women and their partners would provide greater insight into specific relationship patterns and communication related to sexuality during this experience. Nurses need to listen to the stories of African American women about the initial experience of discovery, diagnosis, and treatment of breast cancer so they can be more informed advocates for these women. African American women need more information from healthcare providers regarding the whole experience trajectory.

  6. Effects of the 3D bone-to-implant contact and bone stiffness on the initial stability of a dental implant: micro-CT and resonance frequency analyses.

    Science.gov (United States)

    Hsu, J T; Huang, H L; Tsai, M T; Wu, A Y J; Tu, M G; Fuh, L J

    2013-02-01

    This study investigated the effects of bone stiffness (elastic modulus) and three-dimensional (3D) bone-to-implant contact ratio (BIC%) on the primary stabilities of dental implants using micro-computed tomography (micro-CT) and resonance frequency analyses. Artificial sawbone models with five values of elastic modulus (137, 123, 47.5, 22, and 12.4 MPa) comprising two types of trabecular structure (solid-rigid and cellular-rigid) were investigated for initial implant stability quotient (ISQ), measured using the wireless Osstell resonance frequency analyzer. Bone specimens were attached to 2 mm fibre-filled epoxy sheets mimicking the cortical shell. ISQ was measured after placing a dental implant into the bone specimen. Each bone specimen with an implant was subjected to micro-CT scanning to calculate the 3D BIC% values. The similarity of the cellular type of artificial bone to the trabecular structure might make it more appropriate for obtaining accurate values of primary implant stability than solid-bone blocks. For the cellular-rigid bone models, the ISQ increased with the elastic modulus of cancellous bone. The regression correlation coefficient was 0.96 for correlations of the ISQ with the elasticity of cancellous bone and with the 3D BIC%. The initial implant stability was moderately positively correlated with the elasticity of cancellous bone and with the 3D BIC%. Copyright © 2012 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  7. CT Perfusion for Early Response Evaluation of Radiofrequency Ablation of Focal Liver Lesions: First Experience

    Energy Technology Data Exchange (ETDEWEB)

    Marquez, Herman P., E-mail: hermanpaulo.marquezmasquiaran@usz.ch; Puippe, Gilbert; Mathew, Rishi Philip; Alkadhi, Hatem; Pfammatter, Thomas; Fischer, Michael A. [University Hospital Zurich, Department of Diagnostic and Interventional Radiology, Institute of Diagnostic and Interventional Radiology (Switzerland)

    2017-01-15

    PurposeTo investigate the value of perfusion CT (P-CT) for early assessment of treatment response in patients undergoing radiofrequency ablation (RFA) of focal liver lesions.Methods and Materials20 consecutive patients (14 men; mean age 64 ± 14) undergoing P-CT within 24 h after RFA of liver metastases (n = 10) or HCC (n = 10) were retrospectively included. Two readers determined arterial liver perfusion (ALP, mL/min/100 mL), portal liver perfusion (PLP, mL/min/100 mL), and hepatic perfusion index (HPI, %) in all post-RFA lesions by placing a volume of interest in the necrotic central (CZ), the transition (TZ), and the surrounding parenchymal (PZ) zone. Patients were classified into complete responders (no residual tumor) and incomplete responders (residual/progressive tumor) using imaging follow-up with contrast-enhanced CT or MRI after a mean of 57 ± 30 days. Prediction of treatment response was evaluated using the area under the curve (AUC) from receiver operating characteristic analysis.ResultsMean ALP/PLP/HPI of both readers were 4.8/15.4/61.2 for the CZ, 9.9/16.8/66.3 for the TZ and 20.7/29.0/61.8 for the PZ. Interreader agreement of HPI was fair for the CZ (intraclass coefficient 0.713), good for the TZ (0.813), and excellent for the PZ (0.920). For both readers, there were significant differences in HPI of the CZ and TZ between responders and nonresponders (both, P < 0.05). HPI of the TZ showed the highest AUC (0.911) for prediction of residual tumor, suggesting a cut-off value of 76 %.ConclusionIncreased HPI of the transition zone assessed with P-CT after RFA might serve as an early quantitative biomarker for residual tumor in patients with focal liver lesions.

  8. Microscopic lumbar hernietomiya under CT control, experience in the treatment of disk-articular disease

    International Nuclear Information System (INIS)

    Choneva, I.; Amoreti, N.; Kujelstadt, P.

    2013-01-01

    Full text: Introduction Lumbar disc herniation can be treated with lumbar micro-invasive herniotomy under CT control through transforaminal posterolateral or transchannel approach. Percutaneous access by the fine needle probe in combination with X-ray and CT control is a micro - invasive surgery of the spine, which may be considered as an alternative to traditional surgery. The advantages of this method are: the small diameter of the used probe (not more than 16 G or 1,5 mm), allowing the dermal incision to be only a few millimeters as well as the realization of transchannel access, thereby reducing the risk for susceptible ligament injury and the avoidance of bone lesions on the back arc or neighboring muscular structures. Materials and Methods: The aim of this study is to demonstrate that percutaneous lumbar herniotomy under CT control and on posterolateral and foraminal disc herniation with symptoms of pain and root irritation, leads to a significant improvement of the complaints at times immediately postinterventsional and within 6 months ( D1 , D2, D7 , 1, 2 , 6 months) . This lecture presents 55 consecutive patients with symptoms of pain and root irritation, who have made significant progress after percutaneous lumbar herniotomy under CT control and who did not have satisfactory results despite an adapted medical treatment. All patients were clinically evaluated by using visual analogue scales (VAS) for pain, lumbar and root irritation, as well as by MR images postoperatively. Results: All 55 patients showed immediate postoperative improvement of clinical symptoms and signs. Postoperative MR images also show root decompression. It is not reported about complications during the procedure. After the first week it was noted a reduction in average VAS values of 71% and 67% in patients treated for posterolateral and foraminal herniated disc; in medial disc hernia it was noted an average reduction of only 45% . Six months after micro surgery treatment a positive

  9. Commissioning and initial experimental program of the BGO-OD experiment at ELSA

    Science.gov (United States)

    Alef, S.; Bauer, P.; Bayadilov, D.; Beck, R.; Becker, M.; Bella, A.; Bielefeldt, P.; Böse, S.; Braghieri, A.; Brinkmann, K.; Cole, P.; Di Salvo, R.; Dutz, H.; Elsner, D.; Fantini, A.; Freyermuth, O.; Friedrich, S.; Frommberger, F.; Ganenko, V.; Geffers, D.; Gervino, G.; Ghio, F.; Görtz, S.; Gridnev, A.; Gutz, E.; Hammann, D.; Hannappel, J.; Hillert, W.; Ignatov, A.; Jahn, R.; Joosten, R.; Jude, T. C.; Klein, F.; Knaust, J.; Kohl, K.; Koop, K.; Krusche, B.; Lapik, A.; Levi Sandri, P.; Lopatin, I. V.; Mandaglio, G.; Messi, F.; Messi, R.; Metag, V.; Moricciani, D.; Mushkarenkov, A.; Nanova, M.; Nedorezov, V.; Novinskiy, D.; Pedroni, P.; Reitz, B.; Romaniuk, M.; Rostomyan, T.; Rudnev, N.; Schaerf, C.; Scheluchin, G.; Schmieden, H.; Stugelev, A.; Sumachev, V.; Tarakanov, V.; Vegna, V.; Walther, D.; Watts, D.; Zaunick, H.; Zimmermann, T.

    2016-11-01

    BGO-OD is a new meson photoproduction experiment at the ELSA facility of Bonn University. It aims at the investigation of non strange and strange baryon excitations, and is especially designed to be able to detect weekly bound meson-baryon type structures. The setup for the BGO-OD experiment is presented, the characteristics of the photon beam and the detector performances are shown and the initial experimental program is discussed.

  10. Integrated cardio-thoracic imaging with ECG-Gated 64-slice multidetector-row CT: initial findings in 133 patients

    International Nuclear Information System (INIS)

    Salem, Randa; Remy-Jardin, Martine; Delhaye, Damien; Khalil, Chadi; Teisseire, Antoine; Remy, Jacques; Delannoy-Deken, Valerie; Duhamel, Alain

    2006-01-01

    The purpose of this study was to investigate the possibility of assessing the underlying respiratory disease as well as cardiac function during ECG-gated CT angiography of the chest with 64-slice multidetector-row CT (MDCT). One hundred thirty-three consecutive patients in sinus rhythm with known or suspected ventricular dysfunction underwent an ECG-gated CT angiographic examination of the chest without β-blockers using the following parameters: (1) collimation: 32 x 0.6 mm with z-flying focal spot for the acquisition of 64 overlapping 0.6-mm slices (Sensation 64; Siemens); rotation time: 0.33 s; pitch: 0.3; 120 kV; 200 mAs; ECG-controlled dose modulation (ECG-pulsing) and (2) 120 ml of a 35% contrast agent. Data were reconstructed: (1) to evaluate the underlying respiratory disease (1-mm thick lung and mediastinal scans reconstructed at 55% of the R-R interval; i.e., ''morphologic scans'') and (2) to determine right (RVEF) and left (LVEF) ventricular ejection fractions (short-axis systolic and diastolic images; Argus software; i.e., ''functional scans''). The mean heart rate was 73 bpm (range: 42-120) and the mean scan time was 18.11±2.67 s (range: 10-27). A total of 123 examinations (92%) had both lung and mediastinal images rated as diagnostic scans, whereas 10 examinations (8%) had non-diagnostic images altered by the presence of respiratory-motion artifacts (n=4) or cyclic artifacts related to the use of a pitch value of 0.3 in patients with a very low heart rate during data acquisition (n=6). Assessment of right and left ventricular function was achievable in 124 patients (93%, 95% CI: 88-97%). For these 124 examinations, the mean RVEF was 46.10% (±9.5; range: 20-72) and the mean LVEF was 58.23% (±10.88; range: 20-83). In the remaining nine patients, an imprecise segmentation of the right and left ventricular cavities was considered as a limiting factor for precise calculation of end-systolic and end-diastolic ventricular volumes. The mean (±SD) DLP

  11. Blast experiments for the derivation of initial cloud dimensions after a ''Dirty Bomb'' event

    International Nuclear Information System (INIS)

    Thielen, H.; Schroedl, E.

    2004-01-01

    Basis for the assessment of potential consequences of a ''dirty bomb'' event is the calculation of the atmospheric dispersion of airborne particles. The empirical derivation of parameters for the estimation of the initial pollutant cloud dimensions was the principal purpose for blast experiments performed in the training area Munster in summer 2003 with the participation of several highly engaged German organisations and institutions. The experiments were performed under variation of parameters like mass and kind of explosive, subsurface characteristics or meteorological conditions and were documented by digital video recording. The blasting experiments supplied significant results under reproducible conditions. The initial cloud dimension was primarily influenced by the explosive mass. The influence of other parameters was relatively small and within the range of the experimental uncertainties. Based on these experimental results a new correlation was determined for the empirical estimation of the initial cloud dimensions as a function of explosive mass. The observed initial cloud volumes were more than an order of magnitude smaller than those calculated with other widely-used formulas (e.g. HOTSPOT). As a smaller volume of the initial cloud leads to higher near-ground concentration maxima, our results support an appropriate adjustment of currently employed calculation methods. (orig.)

  12. "Elite" Career-Changers and Their Experience of Initial Teacher Education

    Science.gov (United States)

    Wilkins, Chris

    2017-01-01

    This study explores the motivation of "high-status" professionals to change career and enter teaching, and their experience of undertaking initial teacher education (ITE) programmes in England. The study builds on previous research which found that career-changers are disproportionately more likely to fail to complete their ITE studies,…

  13. Initial experiences of simultaneous laparoscopic resection of colorectal cancer and liver metastases

    NARCIS (Netherlands)

    Hoekstra, L. T.; Busch, O. R. C.; Bemelman, W. A.; van Gulik, T. M.; Tanis, P. J.

    2012-01-01

    Introduction. Simultaneous resection of primary colorectal carcinoma (CRC) and synchronous liver metastases (SLMs) is subject of debate with respect to morbidity in comparison to staged resection. The aim of this study was to evaluate our initial experience with this approach. Methods. Five patients

  14. High/Scope Preschool Key Experiences: Initiative and Social Relations. [with] Curriculum Videotape.

    Science.gov (United States)

    Graves, Michelle

    As preschoolers develop the ability to carry out their ideas and play alone and with others, they are developing the foundation for social competence. This booklet and a companion videotape help teachers and parents recognize and support nine High/Scope key experiences in initiative and social relations: (1) making and expressing choices, plans,…

  15. HDR brachytherapy in carcinoma of cervix: initial experience at AWARE hospitals

    International Nuclear Information System (INIS)

    Rajendran, M.; Reddy, K.D.; Reddy, R.M.; Reddy, J.M.; Reddy, B.V.N.; Kiran Kumar; Gopi, S.; Dharaniraj; Janardhanan

    2002-01-01

    High dose rate (HDR) brachytherapy is well established in the management of gynaecological malignancies. A report on the initial results of one and half year experience with a consistent dose/fractionation schedule and procedure of planning with delivery of treatment schedule is presented

  16. Aortic aneurysm sac pressure measurements after endovascular repair using an implantable remote sensor: initial experience and short-term follow-up

    International Nuclear Information System (INIS)

    Hoppe, Hanno; Kaufman, John A.; Segall, Jocelyn A.; Liem, Timothy K.; Landry, Gregory J.

    2008-01-01

    The purpose of this single-center study was to report our initial experience with an implantable remote pressure sensor for aneurysm sac pressure measurement in patients post-endovascular aneurysm repair (EVAR) including short-term follow-up. A pressure sensor (EndoSure, Atlanta, GA) was implanted in 12 patients treated with different commercially available aortic endografts for EVAR. Pressure was read pre- and post-EVAR in the operating room. One-month follow-up (30 days ± 6 days) was performed including sac pressure readings and IV contrast CT scans. Variables were compared using the paired Student's t test. An intraprocedure type-I endoleak and a type-III endoleak were successfully treated resulting in decreasing sac pressures. In all patients, post-EVAR systolic sac pressure decreased by an average of 33% (P ≤ 0.005) compared to pre-EVAR measurements. One-month follow-up demonstrated a 47% decrease in systolic sac pressure (P ≤ 0.05). On follow-up CT scans, the average maximum aneurysm diameter pre-EVAR was 6.3 ± 1.6 cm and post-EVAR 6.0 ± 1.7 cm (P≤0.05). The diameter of the aneurysm sac was larger only in one patient with a type-III endoleak. Remote sac pressure measurement may provide important information in addition to imaging and may help to reduce the number of follow-up CT scans. (orig.)

  17. Comparison of the initial ETA gas propagation experiments with theoretical models

    Energy Technology Data Exchange (ETDEWEB)

    Chambers, F.W.; Clark, J.C.; Fessenden, T.J.

    1982-04-20

    This report contains a description of the initial ETA propagation experiments in air at a beam current of 4.5 kA. The beam was observed to propagate at the pressures anticipated on the basis of previous theory and experiment. A comparison of measured net current waveforms with predictions of the PHOENIX code showed good agreement over the pressure range 0.1 to 200 torr. However, the beam was observed to expand with Z at a faster rate than theory predicts. Excessive transverse beam modulation at injection complicated the experiments and limited their comparison with theory.

  18. Comparison of the initial ETA gas propagation experiments with theoretical models

    International Nuclear Information System (INIS)

    Chambers, F.W.; Clark, J.C.; Fessenden, T.J.

    1982-01-01

    This report contains a description of the initial ETA propagation experiments in air at a beam current of 4.5 kA. The beam was observed to propagate at the pressures anticipated on the basis of previous theory and experiment. A comparison of measured net current waveforms with predictions of the PHOENIX code showed good agreement over the pressure range 0.1 to 200 torr. However, the beam was observed to expand with Z at a faster rate than theory predicts. Excessive transverse beam modulation at injection complicated the experiments and limited their comparison with theory

  19. Initial experiment of focusing wiggler of MM wave Free Electron Laser on LAX-1

    International Nuclear Information System (INIS)

    Sakamoto, Keishi; Maebara, Sunao; Watanabe, Akihiko; Kishimoto, Yasuaki; Nagashima, Takashi; Maeda, Hikosuke; Shiho, Makoto; Oda, Hisako; Kawasaki, Sunao.

    1991-03-01

    Initial results of Free Electron laser (FEL) Experiment in the mm wave region are presented. The experiment is carried out using a induction linac system (LAX-1: Large current Accelerator Experiment) of E b = 1 MeV, Ib = 1 ∼ 3 kA. The wiggler of FEL is composed of the curved surface magnets arrays (focusing wiggler), which is found to be effective for a transport of low energy and high current beam through the wiggler. The superradiance of the mm wave region (30 GHz ∼ 40 GHz) is observed. The growth rate of this radiation is 0.42 dB/cm. (author)

  20. The experiences of employees participating in organisational corporate social responsibility initiatives

    Directory of Open Access Journals (Sweden)

    Gretha Cook

    2018-04-01

    Full Text Available Orientation: This article is about the experiences of employees who actively participate in organisational corporate social responsibility (CSR initiatives.   Research purpose: The general aim of this study was to explore the experiences of employees who participate in CSR initiatives within an organisation where a well-developed framework exists.   Motivation for the study: Whilst an emergent number of studies have considered the various dimensions of CSR initiatives, the focus appears to be on stakeholders such as the recipients of CSR, organisations, consumers and shareholders but not the perspective of the employees who actively participate in CSR initiatives.   Research design, approach and method: A qualitative research approach was employed with the intent of exploring the experiences of employees participating in organisational CSR initiatives. Data were collected and analysed from a purposive sample of 12 employees, by means of interactive qualitative analysis.   Main findings: The study revealed that the primary driver that motivates employees to participate in CSR is love. Love sparks a sense of compassion. Compassion, coupled with an enabling environment, stimulates generosity. By being generous, a feeling of hope and inspiration is induced in both the givers and receivers of generosity. A secondary outcome of generosity and hope and inspiration is bringing about change to others, and whilst going through this journey and making a difference in the lives of others, participants experience a progressive change within themselves. This change evokes a feeling of fulfilment, and ultimately a feeling of complete joy.   Contributions or value-add: This research complements existing CSR literature by focussing and reporting on the experiences of the employee as an important stakeholder.

  1. Tactics of brain abscess treatment in the CT era -experience, problems, prospects

    International Nuclear Information System (INIS)

    Kroo, M.; Cernoch, Z.; Rezac, O.

    1987-01-01

    26 brain abscesses are analyzed which were treated over a period of five years at the neurosurgical department of the medical faculty of Hradec Kralove (CS), i.e., in the years 1978 -1983. The analysis is focused on the degree to which CT (computerized tomography) affected not only the results but also the tactics of such therapy, which shifted to the benefit of less radical methods, i.e., puncture and drainage. In certain cases, of course, the radical method of excision with capsule cannot be avoided. In exceptional cases CT may be used for documenting the healing of a brain abscess, i.e., of the inflammation focus following conservative treatment with antibiotics only. Of the 26 patients only one was lost. A new problem is presented by very small abscesses in functionally valuable zones of the brain. Here the choice of tactics is more urgent than ever because the physician is concerned not only with saving the life of his patient but with saving the quality of his life. (author). 5 figs., 3 tabs., 18 refs

  2. Data-driven CT protocol review and management—experience from a large academic hospital.

    Science.gov (United States)

    Zhang, Da; Savage, Cristy A; Li, Xinhua; Liu, Bob

    2015-03-01

    Protocol review plays a critical role in CT quality assurance, but large numbers of protocols and inconsistent protocol names on scanners and in exam records make thorough protocol review formidable. In this investigation, we report on a data-driven cataloging process that can be used to assist in the reviewing and management of CT protocols. We collected lists of scanner protocols, as well as 18 months of recent exam records, for 10 clinical scanners. We developed computer algorithms to automatically deconstruct the protocol names on the scanner and in the exam records into core names and descriptive components. Based on the core names, we were able to group the scanner protocols into a much smaller set of "core protocols," and to easily link exam records with the scanner protocols. We calculated the percentage of usage for each core protocol, from which the most heavily used protocols were identified. From the percentage-of-usage data, we found that, on average, 18, 33, and 49 core protocols per scanner covered 80%, 90%, and 95%, respectively, of all exams. These numbers are one order of magnitude smaller than the typical numbers of protocols that are loaded on a scanner (200-300, as reported in the literature). Duplicated, outdated, and rarely used protocols on the scanners were easily pinpointed in the cataloging process. The data-driven cataloging process can facilitate the task of protocol review. Copyright © 2015 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  3. Improved overall survival after early recurrence of lung cancer following the introduction of CT-based follow-up for patients initially treated with curative intent by (chemo)radiotherapy (CRT)

    DEFF Research Database (Denmark)

    Hansen, Niels-Chr. G.; Laursen, Christian B.; Jeppesen, Stefan S.

    2017-01-01

    years after the introduction of CT-based follow-up. The difference between the periods is statistically significant (p = 0.009, log rank test).View this table:Conclusion: The CT-based follow-up program has most likely contributed to the improved survival as the survival difference between the periods......Background: After introduction in July 2010 of follow-up by contrast enhanced CT of thorax and upper abdomen every 3 months for two years and then every 6 months for three years we found improved survival after early recurrence in patients initially treated by surgery (Eur Respir J 2015; 46 suppl...

  4. Closing in on the K Edge : Coronary CT Angiography at 100, 80, and 70 kV-Initial Comparison of a Second-versus a Third-Generation Dual-Source CT System

    NARCIS (Netherlands)

    Meyer, Mathias; Haubenreisser, Holger; Schoepf, U. Joseph; Vliegenthart, Rozemarijn; Leidecker, Christianne; Allmendinger, Thomas; Lehmann, Ralf; Sudarski, Sonja; Borggrefe, Martin; Schoenberg, Stefan O.; Henzler, Thomas

    2014-01-01

    Purpose: To prospectively evaluate radiation and contrast medium requirements for performing high-pitch coronary computed tomographic (CT) angiography at 70 kV using a third-generation dual-source CT system in comparison to a second-generation dual-source CT system. Materials and Methods: All

  5. Dry preparation for virtual CT colonography with fecal tagging using water-soluble contrast medium: initial results

    International Nuclear Information System (INIS)

    Bielen, Didier; Thomeer, Maarten; Vanbeckevoort, Dirk; Marchal, Guy; Kiss, Gabriel; Maes, Frederik; Rutgeerts, Paul

    2003-01-01

    The purpose of this study was to evaluate the feasibility of a dry bowel preparation, i.e. without laxative fluids, for virtual CT colonography (VCTC), and its impact on patient acceptance compared with conventional colonoscopy (CC). A randomly chosen patient population scheduled for CC (n=11) was first submitted to VCTC after a dry preparation, consisting of low-residue meals combined with a small amount of a iodinated water-soluble contrast medium during each meal 3 days before VCTC. In different colon segments and between different persons, the degree of tagging in VCTC was evaluated and graded. Patient acceptance and future preference were assessed for both preparations as well as for both investigations. The mixing of the contrast with the intestinal content results in contrast impregnated stool, the tagged feces. The degree of fecal tagging was good in the majority of the patients and the colonic segments, especially in the descending colon and sigmoid. Furthermore, patient acceptance and preference were clearly in favour of VCTC compared with CC merely because of the non-invasiveness of the dry preparation. Dry bowel preparation and VCTC is a promising approach towards a patient-friendly colon cancer-screening setup. (orig.)

  6. Evaluation of various image reconstruction parameters in lower extremity stents using multidetector-row CT angiography: initial findings

    International Nuclear Information System (INIS)

    Heuschmid, Martin; Wiesinger, Benjamin; Tepe, Gunnar; Luz, Oliver; Kopp, Andreas F.; Claussen, Claus D.; Duda, Stephan H.

    2007-01-01

    Image quality, visible lumen and patency of lower limb stents was assessed by multidetector-row computed tomography (MDCT) angiography using various reconstruction parameters and the results compared with conventional angiography. Fourteen patients (25 stents) were evaluated. From MDCT datasets, axial and coronal oblique reformations were reconstructed using differing reconstruction parameters (slice thickness, kernel, views). Artifacts and image quality were assessed using a five-degree scale (1=excellent, 5=poor). Visible stent diameter was measured. Stenosis severity was compared with calibrated catheter angiography. The image quality of medium and sharp image kernels were good/fair (1.9-2.4), while smooth kernel provided only acceptable/poor image quality (3.9-4.4). Coronal oblique images were rated superior to assess in-stent lumen rather than axial. Using medium and sharp kernels, the visible stent lumen was significantly greater than using smooth kernel (P<0.001). thirteen out of fourteen patients (24/25 stents) were correctly classified as patent. In one patient, in-stent stenosis (≥50%) was falsely diagnosed using CT angiography (CTA) with smooth kernel and was, therefore, rated as false positive. Coronal oblique views, as well as medium and sharp kernels, have shown the best results regarding image quality to assess stent patency in the lower limb. Therefore, MDCT could be a valuable non-invasive modality for stent imaging in the peripheral vasculature. (orig.)

  7. Initial experiences of family caregivers of survivors of a traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Mandi Broodryk

    2015-08-01

    Full Text Available Background: There seems to be a paucity of research on the initial subjective experiences of family caregivers of survivors of a traumatic brain injury (TBI. Objective: To explore the challenges that family caregivers face during the initial stages of recovery of a relative who has sustained a TBI. Methods: Thematic analysis was used to explore the findings from semi-structured interviews that were conducted with 12 female family caregivers of relatives who had sustained a TBI. Results: Family caregivers recalled their initial experiences of the shock at hearing the news about their relative’s TBI, negative experiences in hospital and frustrating interactions with healthcare professionals as particularly challenging. Conclusion: The findings of this study emphasise caregivers’ need for support, information and psycho-education, especially from healthcare professionals, from the very beginning stages of recovery from a TBI. Practical and physical needs with regard to admission to and care in the hospital were also highlighted. This research will hopefully contribute to creating awareness amongst healthcare professionals on how they can contribute to improvement of the services provided by the healthcare system based on the experiences of the caregivers who participated in this study.

  8. Helical CT angiography of renal arteries: two-years of experience

    International Nuclear Information System (INIS)

    Beregi, J.P.; Louvegny, S.; Ceugnart, L.; Willoteaux, S.; Elkohen, M.; Desmoucelle, F.; Deklunder, G.; Wattinne, L.

    1997-01-01

    To evaluate the role of helical CT angiography (CTA) in the detection of renal artery stenosis in hypertensive patients. We studied 300 hypertensive patients (50 prospectively and 250 consecutively) with CTA and arteriography (n = 118). Helical acquisition (collimation 3 mm; pitch = 1, 20 seconds acquisition time) was performed 20-45 seconds after contrast injection (300 mgl/ml; 120 ml, 4 ml/sec. Transverse axial views and 3D reconstructions were analysed (360 deg interpolation algorithm, 1 mm overlapped). In the prospective series, CTA sensibility was 100 % for main renal artery stenoses and specificity was 98.2 %; however 7/32 renal accessory arteries were not visualized. In the 300 patients studies, seventy-four stenoses were detected. There were 5 false-positive and 5 false-negative studies. Secondary hypertension was detected in 26 % of patients (including 14 cases of adrenal hyperplasia). CTA is a promising technique for the detection of renal artery stenosis in hypertensive patients. (authors)

  9. Primary squamous cell carcinoma of the thyroid. Initial assessment and follow-up using 18F-FDG PET/CT.

    Science.gov (United States)

    Caballero Gullón, L; Carmona González, E; Martínez Estévez, A; Gómez Camarero, M P; Corral, J J; Borrego Dorado, I

    Squamous cell carcinoma of thyroid is an uncommon, very aggressive neoplasm, having a poor prognosis and poor response to chemotherapy and radiotherapy. Surgery is the initial treatment of choice, although it often presents as a widespread disease at the time of diagnosis, usually with cervical swelling that causes most of the symptoms due to local infiltration or metastasis. Local infiltration from adjacent tumour and metastatic disease needs to be excluded from other primary epidermoid carcinomas, in order to make a correct diagnosis. This also requires the typical cytokeratin pattern seen in histological studies. The case is presented of a 53 year-old man with a medical history of hepatocarcinoma, with a cervical hypermetabolic lesion detected in an 18 F-FDG PET/CT performed to exclude widespread disease. The follow-up of this lesion with this technique and its usefulness is also described. Copyright © 2017 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

  10. Initial implementation of the conversion from the energy-subtracted CT number to electron density in tissue inhomogeneity corrections: An anthropomorphic phantom study of radiotherapy treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Tsukihara, Masayoshi [Division of Radiological Technology, Graduate School of Health Sciences, Niigata University, Niigata 951-8518 (Japan); Noto, Yoshiyuki [Department of Radiology, Niigata University Medical and Dental Hospital, Niigata 951-8520 (Japan); Sasamoto, Ryuta; Hayakawa, Takahide; Saito, Masatoshi, E-mail: masaito@clg.niigata-u.ac.jp [Department of Radiological Technology, School of Health Sciences, Faculty of Medicine, Niigata University, Niigata 951-8518 (Japan)

    2015-03-15

    Purpose: To achieve accurate tissue inhomogeneity corrections in radiotherapy treatment planning, the authors had previously proposed a novel conversion of the energy-subtracted computed tomography (CT) number to an electron density (ΔHU–ρ{sub e} conversion), which provides a single linear relationship between ΔHU and ρ{sub e} over a wide range of ρ{sub e}. The purpose of this study is to present an initial implementation of the ΔHU–ρ{sub e} conversion method for a treatment planning system (TPS). In this paper, two example radiotherapy plans are used to evaluate the reliability of dose calculations in the ΔHU–ρ{sub e} conversion method. Methods: CT images were acquired using a clinical dual-source CT (DSCT) scanner operated in the dual-energy mode with two tube potential pairs and an additional tin (Sn) filter for the high-kV tube (80–140 kV/Sn and 100–140 kV/Sn). Single-energy CT using the same DSCT scanner was also performed at 120 kV to compare the ΔHU–ρ{sub e} conversion method with a conventional conversion from a CT number to ρ{sub e} (Hounsfield units, HU–ρ{sub e} conversion). Lookup tables for ρ{sub e} calibration were obtained from the CT image acquisitions for tissue substitutes in an electron density phantom (EDP). To investigate the beam-hardening effect on dosimetric uncertainties, two EDPs with different sizes (a body EDP and a head EDP) were used for the ρ{sub e} calibration. Each acquired lookup table was applied to two radiotherapy plans designed using the XiO TPS with the superposition algorithm for an anthropomorphic phantom. The first radiotherapy plan was for an oral cavity tumor and the second was for a lung tumor. Results: In both treatment plans, the performance of the ΔHU–ρ{sub e} conversion was superior to that of the conventional HU–ρ{sub e} conversion in terms of the reliability of dose calculations. Especially, for the oral tumor plan, which dealt with dentition and bony structures, treatment

  11. Imaging features of primary Sarcomas of the great vessels in CT, MRI and PET/CT: a single-center experience

    International Nuclear Information System (INIS)

    Falck, Christian von; Meyer, Bernhard; Fegbeutel, Christine; Länger, Florian; Bengel, Frank; Wacker, Frank; Rodt, Thomas

    2013-01-01

    To investigate the imaging features of primary sarcomas of the great vessels in CT, MRI and 18 F-FDG PET/CT. Thirteen patients with a primary sarcoma of the great vessels were retrospectively evaluated. All available images studies including F-18 FDG PET(/CT) (n = 4), MDCT (n = 12) and MRI (n = 6) were evaluated and indicative image features of this rare tumor entity were identified. The median interval between the first imaging study and the final diagnosis was 11 weeks (0–12 weeks). The most frequently observed imaging findings suggestive of malignant disease in patients with sarcomas of the pulmonary arteries were a large filling defect with vascular distension, unilaterality and a lack of improvement despite effective anticoagulation. In patients with aortic sarcomas we most frequently observed a pedunculated appearance and an atypical location of the filling defect. The F-18 FDG PET(/CT) examinations demonstrated an unequivocal hypermetabolism of the lesion in all cases (4/4). MRI proved lesion vascularization in 5/6 cases. Intravascular unilateral or atypically located filling defects of the great vessels with vascular distension, a pedunculated shape and lack of improvement despite effective anticoagulation are suspicious for primary sarcoma on MDCT or MRI. MR perfusion techniques can add information on the nature of the lesion but the findings may be subtle and equivocal. F-18 FDG PET/CT may have a potential role in these patients and may be considered as part of the imaging workup

  12. Preparing beginning reading teachers: An experimental comparison of initial early literacy field experiences

    OpenAIRE

    Al Otaiba, Stephanie; Lake, Vickie E.; Greulich, Luana; Folsom, Jessica S.; Guidry, Lisa

    2012-01-01

    This randomized-control trial examined the learning of preservice teachers taking an initial Early Literacy course in an early childhood education program and of the kindergarten or first grade students they tutored in their field experience. Preservice teachers were randomly assigned to one of two tutoring programs: Book Buddies and Tutor Assisted Intensive Learning Strategies (TAILS), which provided identical meaning-focused instruction (shared book reading), but differed ...

  13. SPINAL CORD STIMULATION IN TREATMENT OF THE NEUROPATHIC PAIN SYNDROMES: INITIAL EXPERIENCE

    Directory of Open Access Journals (Sweden)

    D. A. Rzaev

    2010-01-01

    Full Text Available In the article initial experience of spinal cord stimulation for chronic pain syndromes is described. The trial was done for 62 patients, in 52 cases trial was successful and subcutaneous pulse generator were implanated. Maximal follow-up is 26 months. The level of pain evaluates at VAS. Permanent pain-relieve results were achieved in 46 patients (74,2%. These results correspond to literature data.

  14. Analysis of molten fuel-coolant interaction during a reactivity-initiated accident experiment

    International Nuclear Information System (INIS)

    El-Genk, M.S.; Hobbins, R.R.

    1981-01-01

    The results of a reactivity-initiated accident experiment, designated RIA-ST-4, are discussed and analyzed with regard to molten fuel-coolant interaction (MFCI). In this experiment, extensive amounts of molten UO 2 fuel and zircaloy cladding were produced and fragmented upon mixing with the coolant. Coolant pressurization up to 35 MPa and coolant overheating in excess of 940 K occurred after fuel rod failure. The initial coolant conditions were similar to those in boiling water reactors during a hot startup (that is, coolant pressure of 6.45 MPa, coolant temperature of 538 K, and coolant flow rate of 85 cm 3 /s). It is concluded that the high coolant pressure recorded in the RIA-ST-4 experiment was caused by an energetic MFCI and was not due to gas release from the test rod at failure, Zr/water reaction, or to UO 2 fuel vapor pressure. The high coolant temperature indicated the presence of superheated steam, which may have formed during the expansion of the working fluid back to the initial coolant pressure; yet, the thermal-to-mechanical energy conversion ratio is estimated to be only 0.3%

  15. Thermophysical Property Estimation by Transient Experiments: The Effect of a Biased Initial Temperature Distribution

    Directory of Open Access Journals (Sweden)

    Federico Scarpa

    2015-01-01

    Full Text Available The identification of thermophysical properties of materials in dynamic experiments can be conveniently performed by the inverse solution of the associated heat conduction problem (IHCP. The inverse technique demands the knowledge of the initial temperature distribution within the material. As only a limited number of temperature sensors (or no sensor at all are arranged inside the test specimen, the knowledge of the initial temperature distribution is affected by some uncertainty. This uncertainty, together with other possible sources of bias in the experimental procedure, will propagate in the estimation process and the accuracy of the reconstructed thermophysical property values could deteriorate. In this work the effect on the estimated thermophysical properties due to errors in the initial temperature distribution is investigated along with a practical method to quantify this effect. Furthermore, a technique for compensating this kind of bias is proposed. The method consists in including the initial temperature distribution among the unknown functions to be estimated. In this way the effect of the initial bias is removed and the accuracy of the identified thermophysical property values is highly improved.

  16. Patients' Experiences of Performing Self-care of Stomas in the Initial Postoperative Period.

    Science.gov (United States)

    Lim, Siew Hoon; Chan, Sally Wai Chi; He, Hong-Gu

    2015-01-01

    With the loss of an important bodily function and the distortion in body image, a stoma patient experiences physical, psychological, and social changes. With limited current studies exploring experiences of patients in the management of their stoma, there is a need to explore their experiences, their needs, and factors that influence their self-management. The aim of this study was to investigate patients' experiences of performing self-care of stomas in the initial postoperative period. This study adopted a descriptive qualitative approach from the interpretive paradigm. Semistructured interviews were conducted with 12 patients 1 month postoperatively in a colorectal ward in a hospital in Singapore. Thematic analysis was applied to the interview data. Five themes were identified: process of acceptance and self-management of stoma, physical limitations, psychological reactions, social support, and need for timely and sufficient stoma preparation and education. This study highlights the importance of health professionals' role in helping patients adjust preoperatively and postoperatively and accept the presence of a stoma. Health professionals need to be aware of the physical, psychological, and social impact of stoma on patients in the initial 30-day postoperative period. Research findings informed the type and level of assistance and support to be offered to patients by nurses and the importance of encouraging patients to be involved in stoma care at an early stage, which will ultimately contribute to effective and independent self-management. Patients can be prepared preoperatively to reduce the psychological and social impact of stoma after creation of their stoma.

  17. Coronary imaging quality in routine ECG-gated multidetector CT examinations of the entire thorax: preliminary experience with a 64-slice CT system in 133 patients

    International Nuclear Information System (INIS)

    Delhaye, Damien; Remy-Jardin, Martine; Salem, Randa; Teisseire, Antoine; Khalil, Chadi; Remy, Jacques; Delannoy-Deken, Valerie; Duhamel, Alain

    2007-01-01

    To evaluate image quality in the assessment of the coronary arteries during routine ECG-gated multidetector CT (MDCT) of the chest. One hundred and thirty three patients in sinus rhythm underwent an ECG-gated CT angiographic examination of the entire chest without β-blockers with a 64-slice CT system. In 127 patients (95%), it was possible to assess the coronary arteries partially or totally; coronary artery imaging failed in six patients (5%), leading to a detailed description of the coronary arteries in 127 patients. Considering ten coronary artery segments per patient, 75% of coronary segments were assessable (948/1270 segments). When the distal segments were excluded from the analysis (i.e., seven coronary segments evaluated per patient), the percentage of assessable segments was 86% (768/889 proximal and mid coronary segments) and reached 93% (474/508) when assessing proximal segments exclusively. The mean number of assessable segments was significantly higher in patients with a heart rate ≤80 bpm (n=95) than in patients with a heart rate >80 bpm (n=38) (p<0.002). Proximal and mid-coronary segments can be adequately assessed during a whole-chest ECG-gated CT angiographic examination without administration of β-blockers in patients with a heart rate below 80 bpm. (orig.)

  18. Initial cathode processing experiences and results for the treatment of spent fuel

    International Nuclear Information System (INIS)

    Westphal, B.R.; Laug, D.V.; Brunsvold, A.R.; Roach, P.D.

    1996-01-01

    As part of the spent fuel treatment demonstration at Argonne National Laboratory, a vacuum distillation process is being employed for the recovery of uranium following an electrorefining process. Distillation of a salt electrolyte, primarily consisting of a eutectic mixture of lithium and potassium chlorides, from uranium is achieved by a batch operation termed ''cathode processing.'' Cathode processing is performed in a retort furnace which enables the production of a stable uranium product that can be isotopically diluted and stored. To date, experiments have been performed with two distillation units; one for prototypical testing and the other for actual spent fuel treatment operations. The results and experiences from these initial experiments with both units will be discussed as well as problems encountered and their resolution

  19. Magnetohydrodynamic simulation of solid-deuterium-initiated Z-pinch experiments

    International Nuclear Information System (INIS)

    Sheehey, P.T.

    1994-02-01

    Solid-deuterium-initiated Z-pinch experiments are numerically simulated using a two-dimensional resistive magnetohydrodynamic model, which includes many important experimental details, such as ''cold-start'' initial conditions, thermal conduction, radiative energy loss, actual discharge current vs. time, and grids of sufficient size and resolution to allow realistic development of the plasma. The alternating-direction-implicit numerical technique used meets the substantial demands presented by such a computational task. Simulations of fiber-initiated experiments show that when the fiber becomes fully ionized rapidly developing m=0 instabilities, which originated in the coronal plasma generated from the ablating fiber, drive intense non-uniform heating and rapid expansion of the plasma column. The possibility that inclusion of additional physical effects would improve stability is explored. Finite-Larmor-radius-ordered Hall and diamagnetic pressure terms in the magnetic field evolution equation, corresponding energy equation terms, and separate ion and electron energy equations are included; these do not change the basic results. Model diagnostics, such as shadowgrams and interferograms, generated from simulation results, are in good agreement with experiment. Two alternative experimental approaches are explored: high-current magnetic implosion of hollow cylindrical deuterium shells, and ''plasma-on-wire'' (POW) implosion of low-density plasma onto a central deuterium fiber. By minimizing instability problems, these techniques may allow attainment of higher temperatures and densities than possible with bare fiber-initiated Z-pinches. Conditions for significant D-D or D-T fusion neutron production may be realizable with these implosion-based approaches

  20. Rare case of Primary Pulmonary Extranodal Non-Hodgkin’s Lymphoma in a Patient with Sjogrens Syndrome: Role of FDG-PET/CT in the Initial Staging and Evaluating Response to Treatment

    Directory of Open Access Journals (Sweden)

    Gonca G. Bural

    2012-12-01

    Full Text Available A 64-year old woman with a long standing Sjogren’s syndrome was undergoing evaluation for renal transplant surgery when two pulmonary opacities were detected on chest CT. Subsequent biopsy revealed extranodal marginal B-cell non-Hodgkin’s lymphoma (NHL. An FDG-PET/CT scan was then performed which demonstrated isolated FDG avid pulmonary involvement. After therapy, FDG-PET/CT scans showed good response to treatment with near complete resolution of FDG avidity. This rare case illustrates the rare pulmonary manifestation of extranodal lymphoma in a patient with Sjogren’s syndrome and emphasizes the value of FDG PET/CT in the initial staging and evaluation of response to treatment, which has not previously been published. (MIRT 2012;21:117-120

  1. CT-assisted transcutaneous interstitial implantation of thoracic tumors: Early experience

    International Nuclear Information System (INIS)

    Heelan, R.T.; Hilaris, B.S.; Anderson, L.; Caravelli, J.F.; Nori, D.; Martini, N.; Watson, R.C.; Linares, L.

    1986-01-01

    The authors have transcutaneously implanted I-125 radioactive seeds in six patients with thoracic tumors (three with lung cancer; three with metastases) to determine the feasibility of this procedure. In four patients the thoracic tumors were localized without evidence of distant metastases, but these patients were not candidates for resection because of chronic pulmonary disease. Tumor volume was measured on CT scans (with sagittal and coronal reconstructions) and the required number of seeds was determined based on tumor volume. Between 6 and 11 needles were placed in the tumor and the seeds were implanted as the needle was withdrawn. Between 40 and 60 seeds were implanted in each patient, under local anesthesia. In this preliminary series all patients were found to have tumor attached to pleura. Four of the six patients underwent implantation during a day-time admission to the institution's Adult Day Hospital. No patient suffered any complication as a result of the procedure. Four patients experienced a symptomatic relief of pain and a decrease in size of tumor bulk (local control). Two patients eventually exhibited renewed tumor growth in the edges of the implanted mass after 6 months; the authors plan to supplement future implantations with external radiation therapy. One patient underwent implantation after local recurrence of tumor, returned to work the day following the procedure, and is without evidence of local recurrence 18 months later. They are encouraged by these preliminary results, for several reasons: the lack of morbidity, the achievement of local control of tumor while avoiding surgery and its potential complications, and avoidance of hospital stay (with consequent financial savings). The intent is to expand this series to include patients with lung tumors not attached to pleura

  2. Percutaneous CT-guided radiofrequency ablation of solitary small renal masses. A single center experience

    Energy Technology Data Exchange (ETDEWEB)

    Pieper, C.C.; Fischer, S.; Strunk, H.; Meyer, C.; Thomas, D.; Willinek, W.A.; Schild, H. [Univ. Bonn (Germany). Dept. of Radiology; Hauser, S. [Univ. Bonn (Germany). Dept. of Urology; Nadal, J. [Univ. Bonn (Germany). Inst. for Medical Biometry; Wilhelm, K. [Johanniter Hospital Bonn (Germany). Dept. of Radiology

    2015-07-15

    To analyze the outcome of patients undergoing percutaneous CT-guided radiofrequency ablation (RFA) of small renal masses (SRM) at a single center during a ten-year time period. Patient records of renal RFAs (07/2003 - 11/2013) were reviewed. Indications were SRM suspicious of malignancy on imaging and one of the following: severe comorbidity; old age; solitary kidney; impaired renal function; patient wish. Biopsy was performed at the time of RFA. Patients were excluded if no follow-up was available. Patient and procedural characteristics were recorded. Survival rates were calculated using the Kaplan-Meier's method and compared with log-rank or cox tests. 38 patients (16 females, mean age 70.0 years [range 52 - 87]) presenting with a solitary SRM were included in the study. Biopsy showed malignancy in 29 patients; 9 had benign tumors. 26 patients suffered from cardiovascular, respiratory or hepatic comorbidities. Technical success (complete ablation on first follow-up) was achieved in 95 % of cases. Two major complications (bowel perforation; hematothorax) occurred. The 3- and 7-year overall survival (OS) [any cause] rates were 73.4 ± 0.8 % and 50.3 ± 1.0 %, respectively (mean follow-up 54.6 months, range 1 - 127). 4 recurrences and 2 metastases were observed. The presence of comorbidities was the only independent predictor of OS. There was no difference in survival between patients with benign and malignant tumors. RFA of SRM is successful in a large percentage of cases with a low complication rate and durable local control. As RFA is typically performed in multimorbid patients, overall survival seems to depend primarily on comorbidities rather than cancer progression.

  3. Preliminary experience on the use of PET/CT in the management of pediatric post-transplant lymphoproliferative disorder.

    Science.gov (United States)

    Guerra-García, Pilar; Hirsch, Steffen; Levine, Daniel S; Taj, Mary M

    2017-12-01

    Post-transplant lymphoproliferative disorder (PTLD) is a well-known complication following prolonged immunosuppression. Contrary to other lymphomas, there is no standardized imaging approach to assess PTLD either at staging or for response to therapy. Positron emission tomography/computed tomography (PET/CT) is an imaging modality that has proven to be useful in lymphoma. However, there is still limited data concerning its use in pediatric PTLD. Our study evaluates the use of PET/CT in pediatric PTLD at our institution. To assess the role of PET/CT in pediatric PTLD, we reviewed the pediatric patients with PTLD who had undergone PET/CT at our institution between 2000 and 2016. Nine patients were identified. Six had PET/CT at diagnosis. All lesions seen on CT were identified with PET/CT. Fourteen PET/CTs were done during treatment. Eight PET/CTs were negative, including three where CT showed areas of uncertain significance. In these cases, PET/CT helped us to stop treatment and the patients remain in remission after a long follow-up (mean 74.3 months; range 12.4-180.9 months). PET/CT revealed additional disease in two cases, therefore treatment was intensified. Six biopsies and close follow-up was done to confirm PET/CT results. In one case, PET/CT did not identify central nervous system involvement demonstrated on magnetic resonance imaging. PET/CT may have an important role in the staging and follow-up of pediatric PTLD. In our cohort, PET/CT was helpful in staging and assessing treatment response and in clarifying equivocal findings on other imaging modalities. © 2017 Wiley Periodicals, Inc.

  4. Experience of Initial Symptoms of Breast Cancer and Triggers for Action in Ethiopia

    International Nuclear Information System (INIS)

    Dye, T.D.; Hobden, C.; Reeler, A.; Dye, T.D.; Bogale, S.; Tilahun, Y.; Deressa, T.

    2012-01-01

    Objective. This study assessed the initial experiences, symptoms, and actions of patients in Ethiopia ultimately determined to have breast cancer. Methods. 69 participants in a comprehensive breast cancer treatment program at the main national cancer hospital in Ethiopia were interviewed using mixed qualitative and quantitative approaches. Participants narratives of their initial cancer experience were coded and analyzed for themes around their symptoms, time to seeking advice, triggers for action, and contextual factors. The assessment was approved by the Addis Ababa University Faculty of Medicine Institutional Review Board. Results. Nearly all women first noticed lumps, though few sought medical advice within the first year (average time to action: 1.5 years). Eventually, changes in their symptoms motivated most participants to seek advice. Most participants did not think the initial lump would be cancer, nor was a lump of any particular concern until symptoms changed. Conclusion. Given the frequency with which lumps are the first symptom noticed, raising awareness among participants that lumps should trigger medical consultation could contribute significantly to more rapid medical advice-seeking among women in Ethiopia. Primary care sites should be trained and equipped to offer evaluation of lumps so that women can be referred appropriately for assessment if needed

  5. Initial Scaling Studies and Conceptual Thermal Fluids Experiments for the Prismatic NGNP Point Design

    Energy Technology Data Exchange (ETDEWEB)

    D. M. McEligot; G. E. McCreery

    2004-09-01

    The objective of this report is to document the initial high temperature gas reactor scaling studies and conceptual experiment design for gas flow and heat transfer. The general approach of the project is to develop new benchmark experiments for assessment in parallel with CFD and coupled CFD/ATHENA/RELAP5-3D calculations for the same geometry. Two aspects of the complex flow in an NGNP are being addressed: (1) flow and thermal mixing in the lower plenum ("hot streaking" issue) and (2) turbulence and resulting temperature distributions in reactor cooling channels ("hot channel" issue). Current prismatic NGNP concepts are being examined to identify their proposed flow conditions and geometries over the range from normal operation to decay heat removal in a pressurized cooldown. Approximate analyses are being applied to determine key non-dimensional parameters and their magnitudes over this operating range. For normal operation, the flow in the coolant channels can be considered to be dominant forced convection with slight transverse property variation. The flow in the lower plenum can locally be considered to be a situation of multiple buoyant jets into a confined density-stratified crossflow -- with obstructions. Experiments are needed for the combined features of the lower plenum flows. Missing from the typical jet experiments are interactions with nearby circular posts and with vertical posts in the vicinity of vertical walls - with near stagnant surroundings at one extreme and significant crossflow at the other. Two heat transfer experiments are being considered. One addresses the "hot channel" problem, if necessary. The second experiment will treat heated jets entering a model plenum. Unheated MIR (Matched-Index-of-Refraction) experiments are first steps when the geometry is complicated. One does not want to use a computational technique which will not even handle constant properties properly. The MIR experiment will simulate flow features of the paths of jets

  6. Experience in initial training required for the recognition of the qualified RP expert in Spain

    International Nuclear Information System (INIS)

    Rodriguez Suarez, M.; Marco Arboli, M.; Menarguez, J.

    2003-01-01

    An important point of the actions inside the European framework to achieve the harmonisation of the training programmes and recognition was included in the European directive 96/29/Euratom which includes definition and specific tasks of the European Qualified Expert on Radiation Protection (RP). Basic syllabus for training of those experts was developed in the communication 98/C 133/03 concerning BSS applications. Although, in the Spanish education system, the training and recognition requirements of the high level qualified experts on RP was defined since 1977, until 2001, the figure of the Technical Qualified Expert on RP does not appear in the legal framework. In December 2002, a new regulation of the Spanish Regulatory Body, CSN, about qualifications to obtain the recognition of RP Expert in Spain (both high qualified and technical RP experts) was published. Concerning the qualified expert on RP, (RP Officer), responsible of the RP Service, which takes charge of the effective protection and advise radioactive and nuclear facilities in Rp aspects,has to be authorised by the regulatory body. to obtain the RP officer diploma, conceded by the CSN, an initial training of 300 hours and a three-year minimum experience are required (for X-ray installation a 6-month experience is enough). The technical qualified expert on RP is the worker who carried out the tasks in the a RP Service under the supervision of the RP officer. A Technician Qualified Expert on RP does not need an specific accreditation of the Regulatory Body, but an initial RP training and a three-month minimum experience are required and has hold a certificate by the RP officer. Continuous training is also required and as well has to receive a certificate from the RP officer. Since 1977, The Institute for energy Studies has been implementing specific training courses for those professionals who want to obtain the diploma of RP officer (high degree qualified RP expert), conceded by the CSN. Since then

  7. Basic principles of magnetic resonance imaging in cerebral ischemia and initial clinical experience

    International Nuclear Information System (INIS)

    Brant-Zawadzki, M.; Solomon, M.; Newton, T.H.; Weinstein, P.; Schmidley, J.; Norman, D.

    1985-01-01

    NMR tomography proved to be a method superior to computerized tomography (CT) in terms of sensitivity in the diagnosis of pathological changes in the brain. The article on hand gives a brief survey on the principle of the method and demonstrates the superiority of NMR tomography to CT exemplified by images taken from a number of cases. Instrumental factors influencing diagnosis of cerebral ischaemie are discussed. Clinical studies performed on more than 20 partients with suspected infarct revealed the superiority of NMR tomography to CT. (MG) [de

  8. Initial resident refractive surgical experience: outcomes of PRK and LASIK for myopia.

    Science.gov (United States)

    Wagoner, Michael D; Wickard, Joseph C; Wandling, George R; Milder, Lisa C; Rauen, Matthew P; Kitzmann, Anna S; Sutphin, John E; Goins, Kenneth M

    2011-03-01

    To evaluate and compare the outcome of initial resident surgical experience with photorefractive keratectomy (PRK) and LASIK. Retrospective review of all cases performed with the VISX Star S4 platform (Abbott Medical Optics) between July 1, 2003 and June 30, 2007. Inclusion criteria were spherical equivalent of -0.50 to -10.00 diopters (D), refractive astigmatic error of ≤3.00 D, intention to provide full distance correction, and minimum 3-month postoperative follow-up after initial ablation or retreatment (if performed). A total of 153 cases performed by 20 different residents met the inclusion criteria; 38 eyes underwent PRK and 115 eyes had LASIK. After initial treatment, mean Snellen uncorrected distance visual acuity (UDVA) after PRK was 20/17.3 and after LASIK was 20/19.5. Photorefractive keratectomy was associated with a significantly better approximation between preoperative corrected distance visual acuity (CDVA) and postoperative UDVA (ΔlogMAR 0.009 vs 0.091; P=.004) and a greater percentage of eyes that achieved UDVA of 20/20 or better (94.7% vs 78.3%; P=.02) or 20/30 or better (100% vs 87.8%; P=.02). There was a higher prevalence of retreatment in eyes that underwent LASIK (7.0% vs 0%; P=.20). One (0.9%) eye lost 2 lines of CDVA after LASIK. Supervised refractive surgery residents can achieve excellent visual outcomes in patients operated during their initial refractive experience. Photorefractive keratectomy was associated with better visual outcome than LASIK. Copyright 2011, SLACK Incorporated.

  9. Prototype radiographic system for emergency and intensive care units: Initial experience

    International Nuclear Information System (INIS)

    Mirvis, S.

    1986-01-01

    A prototype radiographic system has been developed for use in bedside examinations in multibed trauma or intensive care units and emergency rooms. The system features a single-phase, high-frequency 30-kW ceiling-mounted generator with an x-ray tube extending from a long counterbalanced arm. All movements are servo-assisted for ease of operation. Based on initial experience, the unit allows easier access to the patient around resuscitation and monitoring equipment, occupies less floor space, and yields better quality images than do standard mobile radiographic units

  10. Initial experience gained with the balance-group system of the Swiss power supply legislation

    International Nuclear Information System (INIS)

    Waldner, M.; Rechsteiner, S.

    2010-01-01

    This article takes a look at the initial experience gained with the Swiss balance-group system. This system was introduced within the framework of Swiss power supply legislation (StromVG - Stromversorgungsgesetz). The balance-group system was considered to be an essential precondition for the implementation of an energy trading business in a liberalised power market. The associated rights and responsibilities and the economic risks involved are discussed in detail. The partners and structures involved in such a balance-group are looked at and basic models for the associated contracts are examined. The relationship between balance-groups and the national power grid Swissgrid are discussed

  11. Transient debris freezing and potential wall melting during a severe reactivity initiated accident experiment

    International Nuclear Information System (INIS)

    El-Genk, M.S.; Moore, R.L.

    1981-01-01

    It is important to light water reactor (LWR) safety analysis to understand the transient freezing of molten core debris on cold structures following a hypothetical core meltdown accident. The purpose of this paper is to (a) present the results of a severe reactivity initiated accident (RIA) in-pile experiment with regard to molten debris distribution and freezing following test fuel rod failure, (b) analyze the transient freezing of molten debris (primarily a mixture of UO/sub 2/ fuel and Zircaloy cladding) deposited on the inner surface of the test shroud wall upon rod failure, and (c) assess the potential for wall melting upon being contacted by the molten debris. 26 refs

  12. Pore Formation and Mobility Investigation (PFMI): Concept, Hardware Development and Initial Analysis of Experiments

    Science.gov (United States)

    Grugel, Richard N.

    2004-01-01

    Porosity in the form of "bubbles and pipes" can occur during controlled directional solidification processing of metal alloys. This is a consequence that 1) precludes obtaining any meaningful scientific results and 2) is detrimental to desired material properties. Unfortunately, several Microgravity experiments have been compromised by porosity. The intent of the PFMI investigation is to conduct a systematic effort directed towards understanding porosity formation and mobility during controlled directional solidification (DS) in a microgravity environment. PFMI uses a pure transparent material, succinonitrile (SCN), as well as SCN "alloyed" with water, in conjunction with a translating temperature gradient stage so that direct observation and recording of pore generation and mobility can be made. PFMI is investigating the role of thermocapillary forces and temperature gradients in affecting bubble dynamics as well as other solidification processes in a microgravity Environment. This presentation will cover the concept, hardware development, operations, and the initial results from experiments conducted aboard the International Space Station. .

  13. Simulation of rod drop experiments in the initial cores of Loviisa and Mochovce

    International Nuclear Information System (INIS)

    Kaloinen, E.; Kyrki-Rajamaeki, R.; Wasastjerna, F.

    1999-01-01

    Interpretation of rod drop measurements during startup tests of the Loviisa reactors has earlier been studied with two-dimensional core calculations using a spatial prompt jump approximation. In these calculations the prediction for the reactivity meter reading was lower than the measured values by 25%. Another approach to solve the problem is simulation of the rod drop experiment with dynamic core calculations coupled with out of core calculations to estimate the response of ex-core ionization chambers for the reactivity meter. This report described the calculations performed with the three-dimensional dynamic code HEXTRAN for prediction of the reactivity meter readings in rod drop experiments in initial cores of the WWER-440 reactors. (Authors)

  14. Mapping patients' experiences from initial symptoms to gout diagnosis: a qualitative exploration.

    Science.gov (United States)

    Liddle, Jennifer; Roddy, Edward; Mallen, Christian D; Hider, Samantha L; Prinjha, Suman; Ziebland, Sue; Richardson, Jane C

    2015-09-14

    To explore patients' experiences from initial symptoms to receiving a diagnosis of gout. Data from in-depth semistructured interviews were used to construct themes to describe key features of patients' experiences of gout diagnosis. A maximum variation sample of 43 UK patients with gout (29 men; 14 women; age range 32-87 years) were recruited from general practices, rheumatology clinics, gout support groups and through online advertising. Severe joint pain, combined with no obvious signs of physical trauma or knowledge of injury, caused confusion for patients attempting to interpret their symptoms. Reasons for delayed consultation included self-diagnosis and/or self-medication, reluctance to seek medical attention, and financial/work pressures. Factors potentially contributing to delayed diagnosis after consultation included reported misdiagnosis, attacks in joints other than the first metatarsophalangeal joint, and female gender. The limitations in using serum uric acid (SUA) levels for diagnostic purposes were not always communicated effectively to patients, and led to uncertainty and lack of confidence in the accuracy of the diagnosis. Resistance to the diagnosis occurred in response to patients' beliefs about the causes of gout and characteristics of the people likely to be affected. Diagnosis prompted actions, such as changes in diet, and evidence was found of self-monitoring of SUA levels. This study is the first to report data specifically about patients' pathways to initial consultation and subsequent experiences of gout diagnosis. A more targeted approach to information provision at diagnosis would improve patients' experiences. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  15. Combined CT Angiography and CT Venography in Thromboembolic disease: clinical impact

    International Nuclear Information System (INIS)

    Bouzas, R.; Migueles, Y.; Gomez, S.; Mallo, R.; Garcia-Tejedor, J. L.; Diaz Vega, M. J.

    2002-01-01

    Combined CT Venography and Pulmonary Angiography was described in 1998 as a tool for diagnostic Thromboembolic Disease. The purpose is to relate our own experience with this technique in a population with suspected pulmonary embolism. 46 consecutive patients with suspected pulmonary embolism underwent combined CT Venography after Pulmonary CT Angiography to depict Deep Venous Thrombosis (DVT). CT Venography where obtained with a 3 minutes delay from injection, without additional intravenous contrast, from upper abdomen to fibular head. A prospective study from emergency reports where used. The reports where aimed by nine different radiologist at diary emergency room (images where not retrospective review). We report if a pulmonary embolus or deep venous thrombus or another alternative diagnostic where done. An endo luminal thrombus in any pulmonary arteries was assessed as a positive study for PE. A Thrombus in the leg veins or in an abdominal vein without diminished size of vein was assessed as an acute DVT. In those patients with a CT negative to Thromboembolic Disease was the clinician who decide if more proves where needed. Those patients without evidence in CT of Thromboembolic Disease where asked for symptoms related to the episode in a 3 months period after initial CT. Patients free of symptoms for 3 months without anticoagulation therapy where considered true negative for CT. CT shows Thromboembolic Disease in 23 of 46 patients. 21PE, 14 DVT 2 of 14 patients with DVT don't show PE, CT excluded thromboembolic disease in 23 patients and in 15 of those patients an alternative diagnostic was shown. In 22 of those 23 patients CT excluded correctly Thromboembolic Disease. One patient result in a false negative CT, Pulmonary Angiography of that patient shows us a subsegmentary embolus. (Author) 9 refs

  16. Quality assurance of 3-D conformal radiation therapy for a cooperative group trial - RTOG 3D QA center initial experience

    International Nuclear Information System (INIS)

    Michalski, Jeff M.; Purdy, James A.; Harms, William B.; Bosch, Walter R.; Oehmke, Frederick; Cox, James D.

    1996-01-01

    's correction and resubmission in 7 of 67 (10.4%) reviewed cases. Normal tissues required correction in 6 of 67 (8.9%) of cases. Initial field shaping differed from the submitted treatment plan by more than 5 mm in significant regions of the field in only 2% of the cases. Isocenter shifts of more than 5 mm on at least one of the treated fields was identified in 7% of initial port films examined. Dosimetry review has demonstrated that 14 of 86 cases (16.3%) had minor variations in target volume coverage (<100% of the target volume coverage by the prescription isodose) and 3.4% had major variation in dose coverage (<95% coverage of target volume by prescription isodose). Nineteen of 93 cases (20%) had more than 7% heterogeneity of dose within the planning target volume. CONCLUSION: 3DCRT can be studied and implemented in a cooperative group setting. Although data exchange problems in this study have been frequent, most of these problems occurred early in the trial and have been resolved in most circumstances. A significant amount of variation has been identified in the definition of target volumes and organs at risk. Similarly, field shaping and port film evaluation showed occasional errors. It is our impression that quality assurance is a critical component of 3DCRT in the cooperative group setting. As experience in the planning of patients with 3DCRT increases, it is expected that the frequency of planning variations will diminish

  17. Intraoperative 3-tesla MRI in the management of paediatric cranial tumours - initial experience

    International Nuclear Information System (INIS)

    Avula, Shivaram; Garlick, Deborah; Abernethy, Laurence J.; Mallucci, Connor L.; Pizer, Barry; Crooks, Daniel

    2012-01-01

    Intraoperative MRI (ioMRI) has been gaining recognition because of its value in the neurosurgical management of cranial tumours. There is limited documentation of its value in children. To review the initial experience of a paediatric 3-Tesla ioMRI unit in the management of cranial tumours. Thirty-eight children underwent ioMRI during 40 cranial tumour resections using a 3-Tesla MR scanner co-located with the neurosurgical operating theatre. IoMRI was performed to assess the extent of tumour resection and/or to update neuronavigation. The intraoperative and follow-up scans, and the clinical records were reviewed. In 27/40 operations, complete resection was intended. IoMRI confirmed complete resection in 15/27 (56%). As a consequence, surgical resection was extended in 5/27 (19%). In 6/27 (22%), ioMRI was equivocal for residual tumour. In 13/40 (33%) operations, the surgical aim was to partially resect the tumour. In 7 of the 13 (54%), surgical resection was extended following ioMRI. In our initial experience, ioMRI has increased the rate of complete resection, with intraoperative surgical strategy being modified in 30% of procedures. Collaborative analysis of ioMRI by the radiologist and neurosurgeon is vital to avoid errors in interpretation. (orig.)

  18. Intraoperative 3-tesla MRI in the management of paediatric cranial tumours - initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Avula, Shivaram; Garlick, Deborah; Abernethy, Laurence J. [Alder Hey Children' s NHS Foundation Trust, Department of Radiology, Liverpool (United Kingdom); Mallucci, Connor L. [Alder Hey Children' s Hospital, Department of Neurosurgery, Liverpool (United Kingdom); Pizer, Barry [Alder Hey Children' s Hospital, Department of Oncology, Liverpool (United Kingdom); Crooks, Daniel [Walton Centre for Neurology and Neurosurgery, Department of Pathology, Liverpool (United Kingdom)

    2012-02-15

    Intraoperative MRI (ioMRI) has been gaining recognition because of its value in the neurosurgical management of cranial tumours. There is limited documentation of its value in children. To review the initial experience of a paediatric 3-Tesla ioMRI unit in the management of cranial tumours. Thirty-eight children underwent ioMRI during 40 cranial tumour resections using a 3-Tesla MR scanner co-located with the neurosurgical operating theatre. IoMRI was performed to assess the extent of tumour resection and/or to update neuronavigation. The intraoperative and follow-up scans, and the clinical records were reviewed. In 27/40 operations, complete resection was intended. IoMRI confirmed complete resection in 15/27 (56%). As a consequence, surgical resection was extended in 5/27 (19%). In 6/27 (22%), ioMRI was equivocal for residual tumour. In 13/40 (33%) operations, the surgical aim was to partially resect the tumour. In 7 of the 13 (54%), surgical resection was extended following ioMRI. In our initial experience, ioMRI has increased the rate of complete resection, with intraoperative surgical strategy being modified in 30% of procedures. Collaborative analysis of ioMRI by the radiologist and neurosurgeon is vital to avoid errors in interpretation. (orig.)

  19. F-18 FDG PET with coincidence detection, dual-head gamma camera, initial experience in oncology

    Energy Technology Data Exchange (ETDEWEB)

    Chu, J.M.G.; Pocock, N.; Quach, T.; Camden, B.M.C. [Liverpool Health Services, Liverpool, NSW (Australia). Department of Nuclear Medicine and Clinical Ultrasound

    1998-06-01

    Full text: The development of Co-incidence Detection (CD) in gamma camera technology has allowed the use of positron radiopharmaceuticals in clinical practice without dedicated PET facilities. We report our initial experience of this technology in Oncological applications. All patients were administered 200 MBq of F- 18 FDG intravenously in a fasting state, with serum glucose below 8.9 mmol/L., and hydration well maintained. Tomography was performed using an ADAC Solus Molecular Co-incidence Detection (MCD) dual-head gamma camera, 60 minutes after administration and immediately after voiding. Tomography of the torso required up to three collections depending on the length of the patient, with each collection requiring 32 steps of 40 second duration, and a 50% overlap. Tomography of the brain required a single collection with 32 steps of 80 seconds. Patients were scanned in the supine position. An iterative reconstruction algorithm was employed without attenuation correction. All patients had histologically confirmed malignancy. Scan findings were correlated with results of all conventional diagnostic imaging procedures that were pertinent to the evaluation and management of each individual patient`s disease. Correlation with tumour type and treatment status was also undertaken. F-18 FDG uptake as demonstrated by CD-PET was increased in tumour bearing sites. The degree of increased uptake varied with tumour type and with treatment status. Our initial experience with CD-PET has been very encouraging, and has led us to undertake prospective short and long term studies to define its role in oncology

  20. Initial Experiences of Simultaneous Laparoscopic Resection of Colorectal Cancer and Liver Metastases

    Directory of Open Access Journals (Sweden)

    L. T. Hoekstra

    2012-01-01

    Full Text Available Introduction. Simultaneous resection of primary colorectal carcinoma (CRC and synchronous liver metastases (SLMs is subject of debate with respect to morbidity in comparison to staged resection. The aim of this study was to evaluate our initial experience with this approach. Methods. Five patients with primary CRC and a clinical diagnosis of SLM underwent combined laparoscopic colorectal and liver surgery. Patient and tumor characteristics, operative variables, and postoperative outcomes were evaluated retrospectively. Results. The primary tumor was located in the colon in two patients and in the rectum in three patients. The SLM was solitary in four patients and multiple in the remaining patient. Surgical approach was total laparoscopic (2 patients or hand-assisted laparoscopic (3 patients. The midline umbilical or transverse suprapubic incision created for the hand port and/or extraction of the specimen varied between 5 and 10 cm. Median operation time was 303 (range 151–384 minutes with a total blood loss of 700 (range 200–850 mL. Postoperative hospital stay was 5, 5, 9, 14, and 30 days. An R0 resection was achieved in all patients. Conclusions. From this initial single-center experience, simultaneous laparoscopic colorectal and liver resection appears to be feasible in selected patients with CRC and SLM, with satisfying short-term results.

  1. The AGING Initiative experience: a call for sustained support for team science networks.

    Science.gov (United States)

    Garg, Tullika; Anzuoni, Kathryn; Landyn, Valentina; Hajduk, Alexandra; Waring, Stephen; Hanson, Leah R; Whitson, Heather E

    2018-05-18

    Team science, defined as collaborative research efforts that leverage the expertise of diverse disciplines, is recognised as a critical means to address complex healthcare challenges, but the practical implementation of team science can be difficult. Our objective is to describe the barriers, solutions and lessons learned from our team science experience as applied to the complex and growing challenge of multiple chronic conditions (MCC). MCC is the presence of two or more chronic conditions that have a collective adverse effect on health status, function or quality of life, and that require complex healthcare management, decision-making or coordination. Due to the increasing impact on the United States society, MCC research has been identified as a high priority research area by multiple federal agencies. In response to this need, two national research entities, the Healthcare Systems Research Network (HCSRN) and the Claude D. Pepper Older Americans Independence Centers (OAIC), formed the Advancing Geriatrics Infrastructure and Network Growth (AGING) Initiative to build nationwide capacity for MCC team science. This article describes the structure, lessons learned and initial outcomes of the AGING Initiative. We call for funding mechanisms to sustain infrastructures that have demonstrated success in fostering team science and innovation in translating findings to policy change necessary to solve complex problems in healthcare.

  2. Prognostic impact of initial maximum standardized uptake value of 18F-FDG PET/CT on treatment response in patients with metastatic lung adenocarcinoma treated with erlotinib

    Directory of Open Access Journals (Sweden)

    Kus T

    2015-12-01

    Full Text Available Tulay Kus,1 Gokmen Aktas,1 Alper Sevinc,1 Mehmet Emin Kalender,1 Mustafa Yilmaz,2 Seval Kul,3 Serdar Oztuzcu,4 Cemil Oktay,5 Celaletdin Camci1 1Department of Internal Medicine, Division of Medical Oncology, Gaziantep Oncology Hospital, 2Department of Nuclear Medicine, 3Department of Biostatistics, Faculty of Medicine, 4Department of Medical Biology, Faculty of Medicine, University of Gaziantep, Gaziantep, 5Department of Radiology, Faculty of Medicine, University of Akdeniz, Antalya, Turkey Purpose: To investigate whether the initial maximum standardized uptake value (SUVmax on fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT has a prognostic significance in metastatic lung adenocarcinoma.Patients and methods: Sixty patients (24 females, mean age: 57.9±12 years with metastatic stage lung adenocarcinoma who used erlotinib and underwent 18F-FDG PET/CT at the time of diagnosis between May 2010 and May 2014 were enrolled in this retrospective study. The patients were stratified according to the median SUVmax value, which was found as 11. Progression-free survival (PFS rates for 3, 6, and 12 months were examined for SUVmax values and epidermal growth factor receptor (EGFR mutation status.Results: The number of EGFR-sensitizing mutation positive/negative/unknown was 26/17/17, respectively, and the number of patients using erlotinib at first-line, second-line, and third-line therapy was 15, 31, and 14 consecutively. The PFS rates of EGFR mutation positive, negative, and unknown patients for 3 months were 73.1%, 35.3%, and 41.2% (P=0.026, odds ratio [OR]=4.39; 95% confidence interval [CI]: 1.45–13.26, respectively. The PFS rates of EGFR positive, negative, and unknown patients for 6 months were 50%, 29.4%, and 29.4% (P=0.267, OR: 2.4; 95% CI: 0.82–6.96, respectively. The PFS rates of EGFR positive, negative, and unknown patients for 12 months were 42.3%, 29.4%, 23.5% (P=0.408, OR: 2.0; 95% CI: 0.42

  3. Using Controlled Landslide Initiation Experiments to Test Limit-Equilibrium Analyses of Slope Stability

    Science.gov (United States)

    Reid, M. E.; Iverson, R. M.; Brien, D. L.; Iverson, N. R.; Lahusen, R. G.; Logan, M.

    2004-12-01

    Most studies of landslide initiation employ limit equilibrium analyses of slope stability. Owing to a lack of detailed data, however, few studies have tested limit-equilibrium predictions against physical measurements of slope failure. We have conducted a series of field-scale, highly controlled landslide initiation experiments at the USGS debris-flow flume in Oregon; these experiments provide exceptional data to test limit equilibrium methods. In each of seven experiments, we attempted to induce failure in a 0.65m thick, 2m wide, 6m3 prism of loamy sand placed behind a retaining wall in the 31° sloping flume. We systematically investigated triggering of sliding by groundwater injection, by prolonged moderate-intensity sprinkling, and by bursts of high intensity sprinkling. We also used vibratory compaction to control soil porosity and thereby investigate differences in failure behavior of dense and loose soils. About 50 sensors were monitored at 20 Hz during the experiments, including nests of tiltmeters buried at 7 cm spacing to define subsurface failure geometry, and nests of tensiometers and pore-pressure sensors to define evolving pore-pressure fields. In addition, we performed ancillary laboratory tests to measure soil porosity, shear strength, hydraulic conductivity, and compressibility. In loose soils (porosity of 0.52 to 0.55), abrupt failure typically occurred along the flume bed after substantial soil deformation. In denser soils (porosity of 0.41 to 0.44), gradual failure occurred within the soil prism. All failure surfaces had a maximum length to depth ratio of about 7. In even denser soil (porosity of 0.39), we could not induce failure by sprinkling. The internal friction angle of the soils varied from 28° to 40° with decreasing porosity. We analyzed stability at failure, given the observed pore-pressure conditions just prior to large movement, using a 1-D infinite-slope method and a more complete 2-D Janbu method. Each method provides a static

  4. The Lusi seismic experiment: An initial study to understand the effect of seismic activity to Lusi

    Energy Technology Data Exchange (ETDEWEB)

    Karyono, E-mail: karyonosu@gmail.com [Agency for Meteorology, Climatology and Geophysics (BMKG), Jakarta (Indonesia); OSLO University (Norway); Padjadjaran University (UNPAD), Bandung (Indonesia); Mazzini, Adriano; Sugiharto, Anton [OSLO University (Norway); Lupi, Matteo [ETH Zurich (Switzerland); Syafri, Ildrem [Padjadjaran University (UNPAD), Bandung (Indonesia); Masturyono,; Rudiyanto, Ariska; Pranata, Bayu; Muzli,; Widodo, Handi Sulistyo; Sudrajat, Ajat [Agency for Meteorology, Climatology and Geophysics (BMKG), Jakarta (Indonesia)

    2015-04-24

    The spectacular Lumpur Sidoarjo (Lusi) eruption started in northeast Java on the 29 of May 2006 following a M6.3 earthquake striking the island [1,2]. Initially, several gas and mud eruption sites appeared along the reactivated strike-slip Watukosek fault system [3] and within weeks several villages were submerged by boiling mud. The most prominent eruption site was named Lusi. The Lusi seismic experiment is a project aims to begin a detailed study of seismicity around the Lusi area. In this initial phase we deploy 30 seismometers strategically distributed in the area around Lusi and along the Watukosek fault zone that stretches between Lusi and the Arjuno Welirang (AW) complex. The purpose of the initial monitoring is to conduct a preliminary seismic campaign aiming to identify the occurrence and the location of local seismic events in east Java particularly beneath Lusi.This network will locate small event that may not be captured by the existing BMKG network. It will be crucial to design the second phase of the seismic experiment that will consist of a local earthquake tomography of the Lusi-AW region and spatial and temporal variations of vp/vs ratios. The goal of this study is to understand how the seismicity occurring along the Sunda subduction zone affects to the behavior of the Lusi eruption. Our study will also provide a large dataset for a qualitative analysis of earthquake triggering studies, earthquake-volcano and earthquake-earthquake interactions. In this study, we will extract Green’s functions from ambient seismic noise data in order to image the shallow subsurface structure beneath LUSI area. The waveform cross-correlation technique will be apply to all of recordings of ambient seismic noise at 30 seismographic stations around the LUSI area. We use the dispersive behaviour of the retrieved Rayleigh waves to infer velocity structures in the shallow subsurface.

  5. Operation of the tokamak fusion test reactor tritium systems during initial tritium experiments

    International Nuclear Information System (INIS)

    Anderson, J.L.; Gentile, C.; Kalish, M.; Kamperschroer, J.; Kozub, T.; LaMarche, P.; Murray, H.; Nagy, A.; Raftopoulos, S.; Rossmassler, R.; Sissingh, R.; Swanson, J.; Tulipano, F.; Viola, M.; Voorhees, D.; Walters, R.T.

    1995-01-01

    The high power D-T experiments on the tokamak fusion test reactor (TFTR) at the Princeton Plasma Physics Laboratory commenced in November 1993. During initial operation of the tritium systems a number of start-up problems surfaced and had to be corrected. These were corrected through a series of system modifications and upgrades and by repair of failed or inadequate components. Even as these operational concerns were being addressed, the tritium systems continued to support D-T operations on the tokamak. During the first six months of D-T operations more than 107kCi of tritium were processed successfully by the tritium systems. D-T experiments conducted at TFTR during this period provided significant new data. Fusion power in excess of 9MW was achieved in May 1994. This paper describes some of the early start-up issues, and reports on the operation of the tritium system and the tritium tracking and accounting system during the early phase of TFTR D-T experiments. (orig.)

  6. Measuring health systems strength and its impact: experiences from the African Health Initiative.

    Science.gov (United States)

    Sherr, Kenneth; Fernandes, Quinhas; Kanté, Almamy M; Bawah, Ayaga; Condo, Jeanine; Mutale, Wilbroad

    2017-12-21

    Health systems are essential platforms for accessible, quality health services, and population health improvements. Global health initiatives have dramatically increased health resources; however, funding to strengthen health systems has not increased commensurately, partially due to concerns about health system complexity and evidence gaps demonstrating health outcome improvements. In 2009, the African Health Initiative of the Doris Duke Charitable Foundation began supporting Population Health Implementation and Training Partnership projects in five sub-Saharan African countries (Ghana, Mozambique, Rwanda, Tanzania, and Zambia) to catalyze significant advances in strengthening health systems. This manuscript reflects on the experience of establishing an evaluation framework to measure health systems strength, and associate measures with health outcomes, as part of this Initiative. Using the World Health Organization's health systems building block framework, the Partnerships present novel approaches to measure health systems building blocks and summarize data across and within building blocks to facilitate analytic procedures. Three Partnerships developed summary measures spanning the building blocks using principal component analysis (Ghana and Tanzania) or the balanced scorecard (Zambia). Other Partnerships developed summary measures to simplify multiple indicators within individual building blocks, including health information systems (Mozambique), and service delivery (Rwanda). At the end of the project intervention period, one to two key informants from each Partnership's leadership team were asked to list - in rank order - the importance of the six building blocks in relation to their intervention. Though there were differences across Partnerships, service delivery and information systems were reported to be the most common focus of interventions, followed by health workforce and leadership and governance. Medical products, vaccines and technologies, and

  7. Detection of aneurysmal subarachnoid hemorrhage 3 months after initial bleeding: evaluation of T2* and FLAIR MR sequences at 3 T in comparison with initial non-enhanced CT as a gold standard.

    Science.gov (United States)

    Mulé, Sébastien; Soize, Sébastien; Benaissa, Azzedine; Portefaix, Christophe; Pierot, Laurent

    2016-08-01

    To investigate the ability of T2* and fluid-attenuated inversion recovery (FLAIR) MR sequences to detect hemosiderin deposition 3 months after aneurysmal subarachnoid hemorrhage (SAH) in comparison with early non-enhanced CT (NECT) as a gold standard. From September 2008 through May 2013, patients with aneurysmal SAH were included if a NECT less than 24 h after the onset of symptoms showed a SAH, and MRI, including T2* and FLAIR sequences, was performed 3 months later. All aneurysms were treated endovascularly. NECT and MR sequences were blindly analyzed for the presence of SAH (NECT) or hemosiderin deposition (MRI). When positive, details of the spatial distribution of SAH or hemosiderin deposits were noted. Sensitivities were calculated for each patient. Sensitivities, specificities, and positive predictive values (PPVs) were calculated for each location. Forty-nine patients (mean age 52.9 years) were included. Bleeding-related patterns were identified in 43 patients (87.8%) on T2* and 10 patients (20.4%) on FLAIR. T2* was highly predictive of the location of the initial hemorrhage, especially in the Sylvian cisterns (PPVs 95% and 100%) and the anterior interhemispheric fissure (PPV 90%). The T2* sequence can detect and localize a previous SAH a few months after aneurysmal bleeding. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  8. Preliminary experiments using light-initiated high explosive for driving thin flyer plates

    International Nuclear Information System (INIS)

    Benham, R.A.

    1980-02-01

    Light-initiated high explosive, silver acelytide - silver-nitrate (SASN), has been used to produce simulated x ray blow-off impulse loading on reentry vehicles to study the system structural response. SASN can be used to accelerate thin flyer plates to high terminal velocities which, in turn, can deliver a pressure pulse that can be tailored to the target material. This process is important for impulse tests where both structural and material response is desired. The theories used to calculate the dynamic state of the flyer plate prior to impact are summarized. Data from several experiments are presented which indicate that thin flyer plates can be properly accelerated and that there are predictive techniques available which are adequate to calculate the motion of the flyer plate. Recommendations are made for future study that must be undertaken to make the SASN flyer plate technique usable

  9. Highlight report local initiatives. Experiences with electric transport; Highlight report lokale initiatieven. Ervaringen met elektrisch vervoer

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-15

    In March 2013 Linkingreen and XTNT started a survey on local electric transportation initiatives. The aim is to learn from the experiences, problems and obstacles of business users of electric vehicles: cars, vans or trucks, scooters, boats and special vehicles (e.g. garbage trucks) that are all-electric or plug-in (with plug). In this brief report, the main results are presented [Dutch] In maart 2013 is door Linkingreen en XTNT in opdracht van Agentschap NL een enquete uitgezet naar lokale initiatieven elektrisch vervoer. Doel is te leren wat de ervaringen, knelpunten en belemmeringen zijn van zakelijke gebruikers van elektrisch vervoer: personenauto's, bestel- of vrachtauto's, scooters, vaartuigen en bijzondere voertuigen (vuilniswagens etc.) die volledig elektrische of plug in (met stekker) zijn. In dit korte verslag zijn de belangrijkste resultaten opgenomen.

  10. Initial experience of using an active beam delivery technique at PSI

    International Nuclear Information System (INIS)

    Pedroni, E.; Boehringer, T.; Coray, A.; Egger, E.; Grossmann, M.; Lin Shixiong; Lomax, A.; Goitein, G.; Roser, W.; Schaffner, B.

    1999-01-01

    At PSI a new proton therapy facility has been assembled and commissioned. The major features of the facility are the spot scanning technique and the very compact gantry. The operation of the facility was started in 1997 and the feasibility of the spot scanning technique has been demonstrated in practice with patient treatments. In this report we discuss the usual initial difficulties encountered in the commissioning of a new technology, the very positive preliminary experience with the system and the optimistic expectations for the future. The long range goal of this project is to parallel the recent developments regarding inverse planning for photons with a similar advanced technology optimized for a proton beam. (orig.)

  11. Initial operating experience and recent development on the TRIUMF optically pumped polarized H- ion source

    International Nuclear Information System (INIS)

    Schmor, P.W.; Law, W.M.; Levy, C.D.P.; McDonald, M.

    1988-01-01

    A polarized H - ion source using optical pumping techniques has been developed at TRIUMF. This source was used to demonstrate (on an ion source test stand) the feasibility of producing 10- μA of ∼ 60% polarized H - ion beam in a dc mode suitable for injection into the TRIUMF cyclotron. The source has been installed in a 300 kV high voltage terminal connected to the cyclotron via a recently constructed beam transport line. A polarization of 80% is anticipated near the end of 1988 after the installation of a superconducting solenoid to the source. In this paper the authors describe the initial operating experience, recent developments, and the future plans for the TRIUMF optically pumped polarized ion source

  12. [A unit for emergency psychiatry and crisis intervention--concepts, structure and initial experiences].

    Science.gov (United States)

    Feuerlein, W; Bronisch, T; Fürmaier, A

    1983-03-01

    The article reports on a ward with 12 beds which has been set up for emergency cases in psychiatry or for immediate intervention in case of a crisis experienced by a patient. In the theoretical part of this article, it is explained that crisis situations are present in most of the psychiatric emergency patients. The article then goes briefly into the fundamentals of therapeutic strategy in such patients: A therapy which helps to uncover hidden conflicts, the pros and cons of therapy focussed on conflict and on supportive measures; as well as a therapy which supports and promotes the ego. This is followed by a comparison of the ward with corresponding facilities in Germany and abroad and a description of their structure, their patients and their function within a psychiatric care system. The concluding part of the article is devoted to a description of the authors' initial experiences and impressions gained during their work with the ward patients, quoting several examples.

  13. Patient experience of CT colonography and colonoscopy after fecal occult blood test in a national screening programme

    Energy Technology Data Exchange (ETDEWEB)

    Plumb, Andrew A.; Taylor, Stuart A.; Halligan, Steve [University College London, Centre for Medical Imaging, Division of Medicine, London (United Kingdom); Ghanouni, Alex; Von Wagner, Christian [University College London, Health Behaviour Research Centre, Department of Epidemiology and Public Health, London (United Kingdom); Rees, Colin J. [Durham University School of Medicine, Pharmacy and Health, Durham (United Kingdom); Hewitson, Paul [University of Oxford, Health Services Research Unit, Nuffield Department of Population Health, Oxford (United Kingdom); Nickerson, Claire; Wright, Suzanne [Fulwood House, NHS Cancer Screening Programmes, Sheffield (United Kingdom)

    2017-03-15

    To investigate patient experience of CT colonography (CTC) and colonoscopy in a national screening programme. Retrospective analysis of patient experience postal questionnaires. We included screenees from a fecal occult blood test (FOBt) based screening programme, where CTC was performed when colonoscopy was incomplete or deemed unsuitable. We analyzed questionnaire responses concerning communication of test risks, test-related discomfort and post-test pain, as well as complications. CTC and colonoscopy responses were compared using multilevel logistic regression. Of 67,114 subjects identified, 52,805 (79 %) responded. Understanding of test risks was lower for CTC (1712/1970 = 86.9 %) than colonoscopy (48783/50975 = 95.7 %, p < 0.0001). Overall, a slightly greater proportion of screenees found CTC unexpectedly uncomfortable (506/1970 = 25.7 %) than colonoscopy (10,705/50,975 = 21.0 %, p < 0.0001). CTC was tolerated well as a completion procedure for failed colonoscopy (unexpected discomfort; CTC = 26.3 %: colonoscopy = 57.0 %, p < 0.001). Post-procedural pain was equally common (CTC: 288/1970,14.6 %, colonoscopy: 7544/50,975,14.8 %; p = 0.55). Adverse event rates were similar in both groups (CTC: 20/2947 = 1.2 %; colonoscopy: 683/64,312 = 1.1 %), but generally less serious with CTC. Even though CTC was reserved for individuals either unsuitable for or unable to complete colonoscopy, we found only small differences in test-related discomfort. CTC was well tolerated as a completion procedure and was extremely safe. CTC can be delivered across a national screening programme with high patient satisfaction. (orig.)

  14. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... a very detailed multidimensional view of the body's interior. Refinements in detector technology allow new CT scanners ... to read. top of page What will my child experience during and after the procedure? CT exams ...

  15. Academics and Learners’ Perceptions on Blended Learning as a Strategic Initiative to Improve Student Learning Experience

    Directory of Open Access Journals (Sweden)

    Ying Adeline Ng Ling

    2017-01-01

    Full Text Available The increasingly tighter shift of socio-economic constraints on higher education sectors in the recent years has called for greater flexibilities in student learning experience both locally and abroad. To this end, we have recently implemented a Blended Learning Initiative in an attempt to provide better learning support and greater flexibility to our students. This initiative is also in line with the University’s aim of having 50% of our learning and teaching delivered on-line by 2020. In this report, we present our findings on academics and learners’ perceptions on the approach which were obtained through surveys. Results showed that blended learning approach was new to the academics and the factors for successful blended learning implementation were identified. Results also showed that learners appreciated the approach as it made learning more accessible and flexible. Furthermore, they also enjoyed the interesting online activities incorporated into their units. In addition, learners were also able to review and pace their own learning. They also perceived that they have the access to the resources and technical ability to cope with online learning materials and activities. Nonetheless, the survey also revealed that learners still prefer to have academics delivering information to them directly rather than a flipped classroom model. In conclusion, findings from this study provide insights that blended learning could be effective to supplement courses offered by the faculty.

  16. Bile Duct Anastomosis Supplied With Biodegradable Stent in Liver Transplantation: The Initial Experience.

    Science.gov (United States)

    Janousek, L; Maly, S; Oliverius, M; Kocik, M; Kucera, M; Fronek, J

    2016-12-01

    The most common biliary complications after orthotopic liver transplantation are bile leaks, anastomotic and intrahepatic strictures, stones, and ampullary dysfunction. These complications can occur in up to 10% to 30% of liver transplant recipients. Leaks occur early in the posttransplant period; the stricture formation typically graduates over time. Ten patients underwent transplantation in our preliminary study: 5 were randomized to the group with stent placement and 5 to the control group. We investigated the role of an absorbable biliary stent with the goal of proving patency of duct-to-duct biliary anastomosis. The stents are made of machine-knitted polydioxanone monofilaments. Our initial results show that duct-to-duct biliary reconstruction using an absorbable internal stent had good patency in all 5 patients. There were no signs of biliary leakage accompanying the anastomoses in any of the cases, and there was no stone formation observed after liver transplantation. The biliary stent was completely absorbed, with no adverse effects. Based on our initial experience and data, we concluded that biodegradable stents can be successfully and safely used in clinical practice. Further large prospective randomized studies are needed to estimate the efficacy of the bioabsorbable stents. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Pediatric CT Scans

    Science.gov (United States)

    The Radiation Epidemiology Branch and collaborators have initiated a retrospective cohort study to evaluate the relationship between radiation exposure from CT scans conducted during childhood and adolescence and the subsequent development of cancer.

  18. Use of a novel percutaneous biopsy localization device: initial musculoskeletal experience

    International Nuclear Information System (INIS)

    Roberts, C.C.; Morrison, W.B.; Deely, D.M.; Zoga, A.C.; Koulouris, G.; Winalski, C.S.

    2007-01-01

    To preliminarily evaluate a new CT-biopsy guidance device, the SeeStar (Radi, Uppsala, Sweden), for use in musculoskeletal applications. The device was evaluated using an imaging phantom and in various simulated clinical biopsy situations. The phantom study was undertaken to optimize the linear metallic artifacts produced by the guidance device. The phantom and guidance device were imaged with CT after altering different imaging parameters, including field of view, filter, focal spot size, kV, mAs, slice thickness and pitch. Clinical biopsy situations were simulated for a superficial biopsy, a deep biopsy and a horizontal biopsy approach. Altering CT parameters had little effect on the subjective appearance of the linear metal artifact, which is used to plan the biopsy approach. Placement of an 18-G needle inside of the biopsy device was subjectively helpful in exaggerating the artifact. Use of this artifact could be helpful in planning biopsy approach for deep lesions or lesions near critical structures. The metal guide on the device adequately supports a standard biopsy needle, making it potentially advantageous for biopsy of superficial lesions and lesions approached from a horizontal orientation. Use of this CT-biopsy guidance device is potentially useful for musculoskeletal applications. The linear metal artifact produced by the device can help plan the biopsy approach. The device can also be useful in biopsy situations where the biopsy needle requires external support during imaging. (orig.)

  19. Initial experience with the new da Vinci single-port robot-assisted platform.

    Science.gov (United States)

    Ballestero Diego, R; Zubillaga Guerrero, S; Truan Cacho, D; Carrion Ballardo, C; Velilla Diez, G; Calleja Hermosa, P; Gutiérrez Baños, J L

    2017-06-01

    To describe our experience in the first cases of urological surgeries performed with the da Vinci single-port robot-assisted platform. We performed 5 single-port robot-assisted surgeries (R-LESS) between May and October 2014. We performed 3 ureteral reimplant surgeries, one ureteropyeloplasty in an inverted kidney and 1 partial nephrectomy. The perioperative and postoperative results were collected, as well as a report of the complications according to the Clavien classification system. Of the 5 procedures, 4 were performed completely by LESS, while 1 procedure was reconverted to multiport robot-assisted surgery. There were no intraoperative complications. We observed perioperative complications in 4 patients, all of which were grade 1 or 2. The mean surgical time was 262minutes (range, 230-300). In our initial experience with the da Vinci device, R-LESS surgery was feasible and safe. There are still a number of limitations in its use, which require new and improved R-LESS platforms. Copyright © 2016 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Robotic resections in hepatobiliary oncology - initial experience with Xi da Vinci system in India.

    Science.gov (United States)

    Chandarana, M; Patkar, S; Tamhankar, A; Garg, S; Bhandare, M; Goel, M

    2017-01-01

    Minimal invasive surgery has proven its advantages over open surgeries in the perioperative period. Food and Drug Administration approved da Vinci robot in 2000. The latest version, da Vinci Xi system has a mobile tower-based robot with several modifications to improve the functionality, versatility, and operative ease. None of the centers have reported exclusively on hepatobiliary oncology using the da Vinci Xi system. We report our initial experience. To study the feasibility, advantages, and discuss the operative technique of da Vinci Xi system in hepatobiliary oncology. Data were analyzed retrospectively from a prospectively maintained database from June 2015 to October 2016. Twenty-five patients with suspected or proven hepatobiliary malignancies were operated. Total robotic technique using da Vinci Xi system was used. Demographic details and perioperative outcomes were noted. Of the 25 surgeries, 14 patients had a suspected gallbladder malignancy, 11 patients had primary or metastatic liver tumor. Median age was 53 years. The average duration of surgery was 225 min with a median blood loss 150 ml. The median postoperative stay was 4 days. The median nodal yield for radical cholecystectomy was seven. Five patients required conversion. Two of these developed postoperative morbidity. Robotic surgery for hepatobiliary oncology is feasible and can be performed safely in experienced hands. Increasing experience in this field may equal or even prove advantageous over conventional or laparoscopic approach in future. A cautious approach with judicious patient selection is the key to establishing robotic surgery as a standard surgical approach.

  1. Student Experiences: the 2013 Cascadia Initiative Expedition Team's Apply to Sail Program

    Science.gov (United States)

    Mejia, H.; Hooft, E. E.; Fattaruso, L.

    2013-12-01

    During the summer of 2013, the Cascadia Initiative Expedition Team led six oceanographic expeditions to recover and redeploy ocean bottom seismometers (OBSs) across the Cascadia subduction zone and Juan de Fuca plate. The Cascadia Initiative (CI) is an onshore/offshore seismic and geodetic experiment to study questions ranging from megathrust earthquakes to volcanic arc structure to the formation, deformation and hydration of the Juan de Fuca and Gorda plates with the overarching goal of understanding the entire subduction zone system. The Cascadia Initiative Expedition Team is a team of scientists charged with leading the oceanographic expeditions to deploy and recover CI OBSs and developing the associated Education and Outreach effort. Students and early career scientists were encouraged to apply to join the cruises via the Cascadia Initiative Expedition Team's Apply to Sail Program. The goal of this call for open participation was to help expand the user base of OBS data by providing opportunities for students and scientists to directly experience at-sea acquisition of OBS data. Participants were required to have a strong interest in learning field techniques, be willing to work long hours at sea assisting in OBS deployment, recovery and preliminary data processing and have an interest in working with the data collected. In total, there were 51 applicants to the Apply to Sail Program from the US and 4 other countries; 21 graduate students as well as a few undergraduate students, postdocs and young scientists from the US and Canada were chosen to join the crew. The cruises lasted from 6 to 14 days in length. OBS retrievals comprised the three first legs, of which the first two were aboard the Research Vessel Oceanus. During each of the retrievals, multiple acoustic signals were sent while the vessel completed a semi-circle around the OBS to accurately determine its position, a final signal was sent to drop the seismometer's anchor, and finally the ship and crew

  2. In Their Own Words: Young Adults' Menthol Cigarette Initiation, Perceptions, Experiences and Regulation Perspectives.

    Science.gov (United States)

    Wackowski, Olivia A; Evans, Kiameesha R; Harrell, Melissa B; Loukas, Alexandra; Lewis, M Jane; Delnevo, Cristine D; Perry, Cheryl L

    2017-02-17

    Menthol cigarettes are disproportionately used by young people and have been called smoking starter products. However, limited qualitative research exists on young adults' perceptions of and experiences with these products, with much of it based on document reviews of the tobacco industry's research. We conducted six focus groups with young adult (ages 18-24) menthol smokers in New Jersey (half with black smokers) between December 2014 and March 2015. Participants were asked open-ended questions about their menthol smoking initiation, preference reasons, substitution behaviors, and perceptions of menthol cigarette risks and regulation. Participants' menthol cigarette initiation and preference were influenced by their perceived popularity, brand recognition, taste, smoothness, satisfaction and access (including as "loosies," typically available for Newport). Some believed menthol cigarettes were less harmful than non-menthol cigarettes when initiating smoking. Many currently believed menthol cigarettes were more harmful because they contained extra "additives," were stronger (ie, requiring fewer cigarettes to feel satisfied), and/or based on hearsay. Many had tried new brand Camel Crush, which was perceived to be especially minty, fun, and attractive for newer smokers. While some used non-menthol cigarettes when menthols were unavailable, many said they would never or almost never substitute. Many acknowledged a menthol cigarettes ban would likely help them quit smoking, even though they did not support the idea. Menthol cigarette initiation is influenced by an interplay of multiple factors including their sensory properties, marketing, perceived popularity and availability. The FDA should continue to pursue closing this flavored cigarette loophole. In this first qualitative study of menthol cigarette use among young adults, we found further evidence that menthol cigarettes can act as starter products because they are perceived as easier to smoke and taste and smell

  3. Initial clinical experience with frameless radiosurgery for patients with intracranial metastases

    International Nuclear Information System (INIS)

    Kamath, Reena; Ryken, Timothy C.; Meeks, Sanford L.; Pennington, Edward C.; Ritchie, Justine; Buatti, John M.

    2005-01-01

    Purpose: To review the initial clinical experience with frameless stereotactic radiosurgery (SRS) for treating intracranial metastatic disease. Methods and Materials: Sixty-four patients received frameless SRS for intracranial metastatic disease. Minimum follow-up was 6 months with none lost to follow-up. Patients had a median of 2 metastases and a maximum of 4. The median number of isocenters was 2 with median arcs of 10 and median dose of 17.5 Gy. Thirteen patients were treated for progressive/recurrent disease after surgical resection or whole brain radiotherapy (WBRT). Fifty-one patients were treated with frameless SRS as an an adjunct to initial treatment. Of the total treated, 17 were treated with SRS alone, 20 were treated with WBRT plus SRS, 16 were treated with surgical resection plus SRS, and the remaining 11 were treated with surgical resection plus WBRT plus SRS. Results: With a median actuarial follow-up period of 8.2 months, ultimate local control was 88%. The median time to progression was 8.1 months. The median overall survival was 8.7 months. Of the 17 patients treated with SRS alone, 86% had ultimate local control with mean overall survival of 7.1 months. Of the 13 patients who received surgical resection plus SRS without WBRT as primary treatment, there was 85% ultimate local control with an overall survival of 10.3 months. Three patients treated with initial surgery alone had recurrence treated with SRS 2-3 months after resection. All these patients obtained local control and median survival was >10 months. Of the 13 patients who received WBRT followed by SRS as boost treatment, 92% had local control and mean overall survival was 7.3 months. Of 7 patients who received SRS after recurrence after WBRT, 100% had local control with median survival of 8.2 months. For 8 patients who received surgery followed by WBRT and SRS, local control was 50%; however, ultimate intracranial control was achieved in 7 of 8 patients with repeat SRS and surgical

  4. Initial clinical assessment of CT-MRI image fusion software in localization of the prostate for 3D conformal radiation therapy

    International Nuclear Information System (INIS)

    Kagawa, Kazufumi; Lee, W. Robert; Schultheiss, Timothy E.; Hunt, Margie A.; Shaer, Andrew H.; Hanks, Gerald E.

    1997-01-01

    Purpose: To assess the utility of image fusion software and compare MRI prostate localization with CT localization in patients undergoing 3D conformal radiation therapy of prostate cancer. Materials and Methods: After a phantom study was performed to ensure the accuracy of image fusion procedure, 22 prostate cancer patients had CT and MRI studies before the start of radiotherapy. Immobilization casts used during radiation treatment were also used for both imaging studies. After the clinical target volume (CTV) (prostate or prostate + seminal vesicles) was defined on CT, slices from the MRI study were reconstructed to precisely match the CT slices by identifying three common bony landmarks on each study. The CTV was separately defined on the matched MRI slices. Data related to the size and location of the prostate were compared between CT and MRI. The spatial relationship between the tip of urethrogram cone on CT and prostate apex seen on MRI was also estimated. Results: The phantom study showed the registration discrepancies between CT and MRI smaller than 1.0 mm in any pair in comparison. The patient study showed a mean image registration error of 0.9 (± 0.6) mm. The average prostate volume was 63.0 (± 25.8) cm 3 and 50.9 (± 22.9) cm 3 determined by CT and MRI, respectively. The difference in prostate location with the two studies usually differed at the base and at the apex of the prostate. On the transverse MRI, the prostate apex was situated 7.1 (± 4.5) mm dorsal and 15.1 (± 4.0) mm cephalad to the tip of urethrogram cone. Conclusions: CT-MRI image fusion study made it possible to compare the two modalities directly. MRI localization of the prostate is more accurate than CT, and indicates the distance from cone to apex is 15 mm. CT-MRI image fusion technique provides valuable supplements to CT technology for more precise targeting of the prostate cancer

  5. Evaluation of tumor recurrences after radical prostatectomy using 18F-Choline PET/CT and 3T multiparametric MRI without endorectal coil: a single center experience.

    Science.gov (United States)

    Couñago, Felipe; Recio, Manuel; Maldonado, Antonio; Del Cerro, Elia; Díaz-Gavela, Ana Aurora; Thuissard, Israel J; Sanz-Rosa, David; Marcos, Francisco José; Olaciregui, Karmele; Mateo, María; Cerezo, Laura

    2016-12-07

    PET/CT alone. The initially planned salvage treatment was modified in 57.8% of patients due to imaging findings. In addition to PSA values, Gleason score, T stage, and PSADT may provide valuable data to identify those patients that are most likely to benefit from undergoing both imaging procedures.

  6. [Evaluation of the influence of humidity and temperature on the drug stability by initial average rate experiment].

    Science.gov (United States)

    He, Ning; Sun, Hechun; Dai, Miaomiao

    2014-05-01

    To evaluate the influence of temperature and humidity on the drug stability by initial average rate experiment, and to obtained the kinetic parameters. The effect of concentration error, drug degradation extent, humidity and temperature numbers, humidity and temperature range, and average humidity and temperature on the accuracy and precision of kinetic parameters in the initial average rate experiment was explored. The stability of vitamin C, as a solid state model, was investigated by an initial average rate experiment. Under the same experimental conditions, the kinetic parameters obtained from this proposed method were comparable to those from classical isothermal experiment at constant humidity. The estimates were more accurate and precise by controlling the extent of drug degradation, changing humidity and temperature range, or by setting the average temperature closer to room temperature. Compared with isothermal experiments at constant humidity, our proposed method saves time, labor, and materials.

  7. CT and MR findings in synovial chondromatosis of the temporo-mandibular joint: our experience and review of literature.

    Science.gov (United States)

    Testaverde, Lorenzo; Perrone, Anna; Caporali, Laura; Ermini, Antonella; Izzo, Luciano; D'Angeli, Ilaria; Impara, Luca; Mazza, Dario; Izzo, Paolo; Marini, Mario

    2011-06-01

    To compare Computed Tomography (CT) and Magnetic Resonance (MR) features and their diagnostic potential in the assessment of Synovial Chondromatosis (SC) of the Temporo-Mandibular Joint (TMJ). Eight patients with symptoms and signs compatible with dysfunctional disorders of the TMJ underwent CT and MR scan. We considered the following parameters: soft tissue involvement (disk included), osteostructural alterations of the joints, loose bodies and intra-articular fluid. These parameters were evaluated separately by two radiologists with a "double blinded method" and then, after agreement, definitive assessment of the parameters was given. CT and MR findings were compared. Histopathological results showed metaplastic synovia in all patients and therefore confirmed diagnosis of SC. MR resulted better than CT in the evaluation of all parameters except the osteostructural alterations of the joints, estimated with more accuracy by CT scan. CT scan is excellent to define bony surfaces of the articular joints and flogistic tissue but it fails in the detection of loose bodies when these are not yet calcified. MR scan therefore is the gold standard when SC is suspected since it can visualize loose bodies at early stage and also evaluate disk condition and eventual extra-articular tissues involvement. The use of T2-weighted images and contrast medium allows identifying intra-articular fluid, estimating its entity and discriminating from sinovial tissue. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

  8. CT and MR findings in synovial chondromatosis of the temporo-mandibular joint: Our experience and review of literature

    Energy Technology Data Exchange (ETDEWEB)

    Testaverde, Lorenzo, E-mail: doctor.lot@gmail.com [Department of Radiological Sciences, Policlinico Umberto I, University ' Sapienza' of Rome, Viale del Policlinico 155, 00161, Rome (Italy); Perrone, Anna; Caporali, Laura; Ermini, Antonella [Department of Radiological Sciences, Policlinico Umberto I, University ' Sapienza' of Rome, Viale del Policlinico 155, 00161, Rome (Italy); Izzo, Luciano; D' Angeli, Ilaria [Department of General Surgery ' Pietro Valdoni' , Policlinico Umberto I, University ' Sapienza' of Rome, Viale del Policlinico 155, 00161, Rome (Italy); Impara, Luca; Mazza, Dario [Department of Radiological Sciences, Policlinico Umberto I, University ' Sapienza' of Rome, Viale del Policlinico 155, 00161, Rome (Italy); Izzo, Paolo [Department of General Surgery ' Pietro Valdoni' , Policlinico Umberto I, University ' Sapienza' of Rome, Viale del Policlinico 155, 00161, Rome (Italy); Marini, Mario [Department of Radiological Sciences, Policlinico Umberto I, University ' Sapienza' of Rome, Viale del Policlinico 155, 00161, Rome (Italy)

    2011-06-15

    Objective: To compare Computed Tomography (CT) and Magnetic Resonance (MR) features and their diagnostic potential in the assessment of Synovial Chondromatosis (SC) of the Temporo-Mandibular Joint (TMJ). Materials and methods: Eight patients with symptoms and signs compatible with dysfunctional disorders of the TMJ underwent CT and MR scan. We considered the following parameters: soft tissue involvement (disk included), osteostructural alterations of the joints, loose bodies and intra-articular fluid. These parameters were evaluated separately by two radiologists with a 'double blinded method' and then, after agreement, definitive assessment of the parameters was given. CT and MR findings were compared. Results: Histopathological results showed metaplastic synovia in all patients and therefore confirmed diagnosis of SC. MR resulted better than CT in the evaluation of all parameters except the osteostructural alterations of the joints, estimated with more accuracy by CT scan. Conclusions: CT scan is excellent to define bony surfaces of the articular joints and flogistic tissue but it fails in the detection of loose bodies when these are not yet calcified. MR scan therefore is the gold standard when SC is suspected since it can visualize loose bodies at early stage and also evaluate disk condition and eventual extra-articular tissues involvement. The use of T2-weighted images and contrast medium allows identifying intra-articular fluid, estimating its entity and discriminating from sinovial tissue.

  9. CT should replace three-view radiographs as the initial screening test in patients at high, moderate, and low risk for blunt cervical spine injury: a prospective comparison.

    Science.gov (United States)

    Bailitz, John; Starr, Frederic; Beecroft, Matthew; Bankoff, Jon; Roberts, Roxanne; Bokhari, Faran; Joseph, Kimberly; Wiley, Dorian; Dennis, Andrew; Gilkey, Susan; Erickson, Paul; Raksin, Patricia; Nagy, Kimberly

    2009-06-01

    An estimated 10,000 Americans suffer cervical spine injuries each year. More than 800,000 cervical spine radiographs (CSR) are ordered annually. The human and healthcare costs associated with these injuries are enormous especially when diagnosis is delayed. Controversy exists in the literature concerning the diagnostic accuracy of CSR, with reported sensitivity ranging from 32% to 89%. We sought to compare prospectively the sensitivity of cervical CT (CCT) to CSR in the initial diagnosis of blunt cervical spine injury for patients meeting one or more of the NEXUS criteria. The study prospectively compared the diagnostic accuracy of CSR to CCT in consecutive patients evaluated for blunt trauma during 23 months at an urban, public teaching hospital and Level I Trauma Center. Inclusion criteria were adult patient, evaluated for blunt cervical spine injury, meeting one or more of the NEXUS criteria. All patients received both three-view CSR and CCT as part of a standard diagnostic protocol. Each CSR and CCT study was interpreted independently by a different radiology attending who was blinded to the results of the other study. Clinically significant injuries were defined as those requiring one or more of the following interventions: operative procedure, halo application, and/or rigid cervical collar. Of 1,583 consecutive patients evaluated for blunt cervical spine trauma, 78 (4.9%) patients received only CCT or CSR and were excluded from the study. Of the remaining 1,505 patients, 78 (4.9%) had evidence of a radiographic injury by CSR or CCT. Of these 78 patients with radiographic injury, 50 (3.3%) patients had clinically significant injuries. CCT detected all patients with clinically significant injuries (100% sensitive), whereas CSR detected only 18 (36% sensitive). Of the 50 patients, 15 were at high risk, 19 at moderate risk, and 16 at low risk for cervical spine injury according to previously published risk stratification. CSR detected clinically significant

  10. Heidelberg Ion Therapy Center (HIT): Initial clinical experience in the first 80 patients

    Energy Technology Data Exchange (ETDEWEB)

    Combs, Stephanie E. (Univ. Hospital of Heidelberg, Dept. of Radiation Oncology, Heidelberg (Germany)), E-mail: Stephanie.Combs@med.uni-heidelberg.de; Ellerbrock, Malte; Haberer, Thomas (Heidelberger Ionenstrahl Therapiezentrum (HIT), Im Neuenheimer Feld 450, 69120 Heidelberg (Germany)) (and others)

    2010-10-15

    The Heidelberg Ion Therapy Center (HIT) started clinical operation in November 2009. In this report we present the first 80 patients treated with proton and carbon ion radiotherapy and describe patient selection, treatment planning and daily treatment for different indications. Patients and methods. Between November 15, 2009 and April 15, 2010, 80 patients were treated at the Heidelberg Ion Therapy Center (HIT) with carbon ion and proton radiotherapy. Main treated indications consisted of skull base chordoma (n = 9) and chondrosarcoma (n = 18), malignant salivary gland tumors (n=29), chordomas of the sacrum (n = 5), low grade glioma (n=3), primary and recurrent malignant astrocytoma and glioblastoma (n=7) and well as osteosarcoma (n = 3). Of these patients, four pediatric patients aged under 18 years were treated. Results. All patients were treated using the intensity-modulated rasterscanning technique. Seventy-six patients were treated with carbon ions (95%), and four patients were treated with protons. In all patients x-ray imaging was performed prior to each fraction. Treatment concepts were based on the initial experiences with carbon ion therapy at the Gesellschaft fuer Schwerionenforschung (GSI) including carbon-only treatments and carbon-boost treatments with photon-IMRT. The average time per fraction in the treatment room per patient was 29 minutes; for irradiation only, the mean time including all patients was 16 minutes. Position verification was performed prior to every treatment fraction with orthogonal x-ray imaging. Conclusion. Particle therapy could be included successfully into the clinical routine at the Dept. of Radiation Oncology in Heidelberg. Numerous clinical trials will subsequently be initiated to precisely define the role of proton and carbon ion radiotherapy in radiation oncology.

  11. Laparoendoscopic single-site extraperitoneal inguinal hernia repair: initial experience in 10 patients.

    Science.gov (United States)

    Do, Minh; Liatsikos, Evangelos; Beatty, John; Haefner, Tim; Dunn, Ian; Kallidonis, Panagiotis; Stolzenburg, Jens-Uwe

    2011-06-01

    Recent technical advances and a trend toward laparoscopic single incision surgery have led us to explore the feasibility of laparoendoscopic single-site (LESS) hernia repair. We present our technique and initial experience with LESS extraperitoneal inguinal hernia repair in 10 consecutive men with unilateral inguinal hernias. Age range was 43.7 (28-64) years. Mean body mass index was 28 (range 24-30). Six were left inguinal hernias. There were six indirect and four direct hernias. Three patients had undergone previous open appendectomy. Incarcerated or bilateral hernias were excluded from our initial series. All cases were performed by three surgeons who were experienced in conventional totally extraperitoneal laparoscopic hernia repair as well as experienced in LESS. A literature review of current single-port inguinal hernia repair data is also presented. The mean operative time was 53 minutes (range 45-65  min). The average length of skin incision was 2.8  cm (range 2.3-3.2  cm). No drain was necessary in any of the patients, while no recordable bleeding was observed. There were no intraoperative or immediate postoperative complications. Hospitalization period was 2 days for all patients. After a limited follow-up of 1 month, there have been no recurrences and no complaints of testicular pain. The results of the current series compare favorably with those found in a literature review. LESS extraperitoneal inguinal hernia repair is both feasible and safe, although more technically demanding than its conventional laparoscopic counterpart. Although the cosmetic result with the former approach may prove superior, there are standing questions regarding the complications and long-term outcome. Randomized and if possible blinded trials that compare conventional and single-incision laparoscopic hernia repair may help to distinguish the most advantageous technique.

  12. Modelling Reactivity-Initiated-Accident Experiments With Falcon And SCANAIR: A Comparison Exercise

    International Nuclear Information System (INIS)

    Romano, A.; Wallin, H.; Zimmermann, M.A.

    2005-01-01

    A critical assessment is made of the state-of-the-art fuel performance code FALCON in the context of selected Reactivity Initiated Accident (RIA) experiments from the CABRI REP Na series, and contrasts its predictions against those of the extensively benchmarked SCANAIR (Version 3.2) code. The thermal fields in the fuel and cladding, the clad mechanical deformation, and the Fission Gas Release (FGR) are adopted as 'Figures of Merit' by which to judge code performance. Particular attention is paid to the importance of fission-gas-induced clad deformation (which is modelled in SCANAIR, but not in FALCON), relative to that driven by the fuel thermal expansion (which is modelled by both codes). The thermal fields calculated by the codes are in good agreement with each other, especially during the initial stages of the transients --- the adiabatic phase. Larger discrepancies are observed at later times, and are due to the different models applied to calculate the gap conductance. FALCON predicts clad permanent deformations at the end of the transients with a maximum deviation from the experimental measurements of about 20%. Generally, the code always tends to underpredict the measurements. SCANAIR performs similarly, but grossly overpredicts the permanent clad strain for the case involving a very energetic pulse. The fission-gas-driven clad deformation is only relevant for very fast pulse energy injection cases, which are not prototypical of the RIA transients expected in PWRs. The FGR models in FALCON do not capture the mechanism of 'burst-release' in the RIA transients, having been developed for steady-state irradiation conditions. This also explains why they performed poorly when applied to the fast-transient cases analyzed here. In contrast, the FGR results from SCANAIR are in satisfactory agreement with the experimental results. (author)

  13. Transanal minimally-invasive surgery (TAMIS: Technique and results from an initial experience

    Directory of Open Access Journals (Sweden)

    Carlos Ramon Silveira Mendes

    2013-10-01

    Full Text Available Transanal endoscopic microsurgery is a minimally-invasive approach for rectal lesions. Superior exposure and access to the entire rectum result in lesser risk of compromised margins and lower recurrence rates, when compared to conventional transanal excision. The aim of this study was to describe a single institution's initial experience with transanal minimally invasive surgery (TAMIS. This was a prospective review of our database. Elev- en procedures from January 2012 to June 2013 were analyzed. Results: eleven operations were completed. Five men were evaluated. Mean age was 62.9 (40-86. Mean follow-up was 9.3 (2-17 months. Average tumor size was 3.8 (1.8-8 cm. Mean distance from anal verge was 6.3 (3-12 cm. Mean operating time was 53.73 (28-118 min. Postoperative complica- tion rate was 9.1%. There were no readmissions. Mortality was null. Operative pathology disclosed the presence of adenoma in four patients, invasive adenocarcinoma in two, neu- roendocrine carcinoma in three, and no residual lesion in one case. TAMIS is a minimally- invasive procedure with low postoperative morbidity at the initial experience. TAMIS is a curative procedure for benign lesions and for selected early cancers. It is useful after neoadjuvant therapy for strictly selected cancers, pending the results of multi-institutional trials. Resumo: Microcirurgia endoscópica transanal é uma abordagem minimamente invasiva para lesões retais. Apresenta menor risco de margem comprometida e menores taxas de recorrência em comparação com excisão transanal convencional. Objetivou-se descrever a experiência inicial, de uma única instituição, com cirurgia minimamente invasiva transanal (TAMIS. Avaliação prospectiva de nosso banco de dados. Onze procedimentos de janeiro de 2012 a junho de 2013, foram analisados. Resultados: onze operações foram concluídas. Havia cinco homens. A média de idade foi de 62,9 (40-86. O acompanhamento médio foi de ww9,3 (2-17 meses. O

  14. It's a question of endurance - Patients with head and neck cancer experiences of 18F-FDG PET/CT in a fixation mask.

    Science.gov (United States)

    Andersson, Camilla; Röing, Marta; Tiblom Ehrsson, Ylva; Johansson, Birgitta

    2017-08-01

    This study aimed to explore how patients with head and neck cancer experienced undergoing an 18 F-fluoro-deoxy-glucose positrons emissions tomography/computed tomography ( 18 F-FDG PET/CT) examination in a fixation mask. Interviews were conducted with nine patients with known or suspected head and neck cancer who were scheduled for the examination for the first time. The phenomenological method according to van Manen and his four lifeworld existentials; lived space, lived body, lived time, and lived relation was used to analyse the interviews. The thoughts and feelings of the patients during the PET/CT examination varied, some found it very difficult, while others did not. However, for all the patients, it was an experience that required some form of coping to maintain composure for example distraction. PET/CT examnation in a fixation mask may be strenuous for some patients. Patients need more detailed information, including suggestions for coping behaviours, prior to the examination, as well as higher level of support during and after the examination. The results of this study may be used to improve patient care and optimize the procedure of PET/CT examination in a fixation mask. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Initial Results from the STEM Student Experiences Aboard Ships (STEMSEAS) Program

    Science.gov (United States)

    Lewis, J. C.; Cooper, S. K.; Thomson, K.; Rabin, B.; Alberts, J.

    2016-12-01

    The Science Technology Engineering and Math Student Experiences Aboard Ships (STEMSEAS) program was created as a response to NSF's call (through GEOPATHS) for improving undergraduate STEM education and enhancing diversity in the geosciences. It takes advantage of unused berths on UNOLS ships during transits between expeditions. During its 2016 pilot year - which consisted of three transits on three different research vessels in different parts of the country, each with a slightly different focus - the program has gained significant insights into how best to create and structure these opportunities and create impact on individual students. A call for applications resulted in nearly 900 applicants for 30 available spots. Of these applicants, 32% are from minority groups underrepresented in the geosciences (Black, Hispanic, or American Indian) and 20% attend community colleges. The program was able to sail socioeconomically diverse cohorts and include women, veterans, and students with disabilities and from two- and four-year colleges. Twenty-three are underrepresented minorities, 6 attend community colleges, 5 attend an HBCU or tribal college, and many are at HSIs or other MSIs. While longer term impact assessment will have to wait, initial results and 6-month tracking for the first cohort indicate that these kinds of relatively short but intense experiences can indeed achieve significant impacts on students' perception of the geosciences, in their understanding of STEM career opportunities, their desire to work in a geoscience lab setting, and to incorporate geosciences into non-STEM careers. Insights were also gained into the successful makeup of mentor/leader groups, factors to consider in student selection, necessary pre- and post-cruise logistics management, follow-up activities, structure of activities during daily life at sea, increasing student networks and access to mentorships, and leveraging of pre-existing resources and ship-based opportunities

  16. Neonatal extracorporeal membrane oxygenation: Initial experience of Hospital de São João

    Directory of Open Access Journals (Sweden)

    G. Rocha

    2014-11-01

    Full Text Available The purpose of this series is to report the initial ECMO experience of the Neonatal Intensive Care Unit of Hospital de São João. The first three clinical cases are reported. Case report 1: a 39 weeks gestational age girl with severe lung hypoplasia secondary to a bilateral congenital diaphragmatic hernia. Case report 2: a 39 weeks gestational age girl with a right congenital diaphragmatic hernia and a tracheal stenosis. Case report 3: a 34 weeks gestational age boy, with 61 days of life, with a Bordetella pertussis pneumonia, severe pulmonary hypertension, shock, hyperleukocytosis and seizures. Resumo: O objetivo desta série é apresentar a experiência inicial da Unidade de Cuidados Intensivos Neonatais do Hospital de São João com ECMO no recém-nascido. São apresentados os 3 primeiros casos. Caso 1: recém-nascido de 39 semanas de idade gestacional, com hipoplasia pulmonar severa secundária a hérnia diafragmática congénita bilateral. Caso 2: recém-nascido de 39 semanas de idade gestacional, com hérnia diafragmática congénita direita e estenose traqueal. Caso 3: pré-termo de 34 semanas de idade gestacional, sexo masculino, com 61 dias de vida, com pneumonia por Bordetella pertussis, hipertensão pulmonar severa, choque, hiperleucocitose e convulsões. Keywords: Extracorporeal membrane oxygenation, Newborn, Congenital diaphragmatic hernia, Tracheal stenosis, Bordetella pertussis infection, Palavras-chave: Oxigenação por membrana extracorporal, Recém-nascido, Hérnia diafragmática congénita, Estenose traqueal, Infeção por Bordetella pertussis

  17. Initial experience with visualizing hand and foot tendons by dual-energy computed tomography.

    Science.gov (United States)

    Deng, Kai; Sun, Cong; Liu, Cheng; Ma, Rui

    2009-01-01

    To assess the feasibility of visualizing hand and foot tendons by dual-energy computed tomography (CT). Twenty patients who suffered from hand or feet pains were scanned on dual-source CT (Definition, Forchheim, Germany) with dual-energy mode at tube voltages of 140 and 80 kV and a corresponding ratio of 1:4 between tube currents. The reconstructed images were postprocessed by volume rendering techniques (VRT) and multiplanar reconstruction (MPR). All of the suspected lesions were confirmed by surgery or follow-up studies. Twelve patients (total of 24 hands and feet, respectively) were found to be normal and the other eight patients (total of nine hands and feet, respectively) were found abnormal. Dual-energy techniques are very useful in visualizing tendons of the hands and feet, such as flexor pollicis longus tendon, flexor digitorum superficialis/profundus tendon, Achilles tendon, extensor hallucis longus tendon, and extensor digitorum longus tendon, etc. It can depict the whole shape of the tendons and their fixation points clearly. Peroneus longus tendon in the sole of the foot was not displayed very well. The distal ends of metacarpophalangeal joints with extensor digitoium tendon and extensor pollicis longus tendon were poorly shown. The lesions of tendons such as the circuitry, thickening, and adherence were also shown clearly. Dual-energy CT offers a new method to visualize tendons of the hand and foot. It could clearly display both anatomical structures and pathologic changes of hand and foot tendons.

  18. Clinical Evaluation of PET Image Quality as a Function of Acquisition Time in a New TOF-PET/MRI Compared to TOF-PET/CT--Initial Results.

    Science.gov (United States)

    Zeimpekis, Konstantinos G; Barbosa, Felipe; Hüllner, Martin; ter Voert, Edwin; Davison, Helen; Veit-Haibach, Patrick; Delso, Gaspar

    2015-10-01

    The purpose of this study was to compare only the performance of the PET component between a TOF-PET/CT (henceforth noted as PET/CT) scanner and an integrated TOF-PET/MRI (henceforth noted as PET/MRI) scanner concerning image quality parameters and quantification in terms of standardized uptake value (SUV) as a function of acquisition time (a surrogate of dose). The CT and MR image quality were not assessed, and that is beyond the scope of this study. Five brain and five whole-body patients were included in the study. The PET/CT scan was used as a reference and the PET/MRI acquisition time was consecutively adjusted, taking into account the decay between the scans in order to expose both systems to the same amount of the emitted signal. The acquisition times were then retrospectively reduced to assess the performance of the PET/MRI for lower count rates. Image quality, image sharpness, artifacts, and noise were evaluated. SUV measurements were taken in the liver and in the white matter to compare quantification. Quantitative evaluation showed strong correlation between PET/CT and PET/MRI brain SUVs. Liver correlation was good, however, with lower uptake estimation in PET/MRI, partially justified by bio-redistribution. The clinical evaluation showed that PET/MRI offers higher image quality and sharpness with lower levels of noise and artifacts compared to PET/CT with reduced acquisition times for whole-body scans while for brain scans there is no significant difference. The TOF-PET/MRI showed higher image quality compared to TOF-PET/CT as tested with reduced imaging times. However, this result accounts mainly for body imaging, while no significant differences were found in brain imaging.

  19. Transluminal Angioplasty of Peroneal Artery Branches in Diabetics: Initial Technical Experience

    International Nuclear Information System (INIS)

    Graziani, Lanfroi; Silvestro, Antonio; Monge, Luca; Boffano, Gian Mario; Kokaly, Francesco; Casadidio, Ilaria; Giannini, Francesco

    2008-01-01

    The present study aimed to report the technical feasibility of percutaneous transluminal angioplasty (PTA) of obstructed or insufficient collateral branches (anterior and posterior perforating branches) from distal peroneal to foot arteries in diabetic patients with chronic critical limb ischemia (CLI) and chronic noncrossable occlusion of the anterior and posterior tibial arteries. Twenty-four diabetic CLI patients (age, 67 ± 8 years; 87% males) undergoing collateral PTA were included. Baseline clinical angiographic and follow-up data were retrospectively reviewed. Collateral PTA was associated with a concomitant PTA of other sites in 21 (83%) cases. In 15 cases the treated collateral linked the peroneal with the plantaris communis; in 9 cases, the peroneal with the dorsalis pedis. Angiographic results of collateral PTA were good in 13 cases (<30% residual stenosis), whereas the result was considered moderate (30%-49% residual stenosis) in the remaining cases. Neither perforation nor acute occlusion of the treated collaterals or other relevant complications were observed. Mean follow-up was 32 ± 17 months. Major amputation was necessary for two (8.3%) patients. Cumulative limb salvage rates at 2 and 4 years were 96% and 87%, respectively. In conclusion, this initial experience shows that PTA of the collateral branches from distal peroneal to foot arteries is a feasible technique. Future studies are required to define the clinical role of this novel approach

  20. The effect of residual ventricular septal defects on early clinical outcome: initial experience

    International Nuclear Information System (INIS)

    Zaman, H.; Cheema, M.A.; Jalal, A.

    2000-01-01

    Residual ventricular septal defect (VSD)after repair of isolated VSD or Fallot's tetralogy is one of the main causes of morbidity and re-operations. In this paper we have presented the results of out initial experience regarding the management of this problem. The data consists of 71 patients (22 isolated VSD and 29 fallout's tetralogy) operate during January 1991 to July, 1993. The incidence of residual VSD as shown by color doppler study at the time of discharge from hospital and at three month's follow-up was 3 out of 60 patients(73%) and 12 out of to (20%) respectively. Six out of these 12 patients were NYHA class III-IV who underwent cardiac catheterization which revealed patch dehiscence in two patients and residual right ventricular outflow tract obstruction in four patients. The two patients, with patch dehiscence were reported successfully with very good outcome. Simple color doppler mapping tends to over-diagnose residual VSDs since it can pick up small haemodynamically insignificant leaks around stitches and needle holes which seal off in due course. The findings of color doppler should, therefore, be correlated with actual clinical outcome in order to proceed with further investigation and re-operation. (author)

  1. Percutaneous fiducial marker placement prior to stereotactic body radiotherapy for malignant liver tumors: an initial experience

    International Nuclear Information System (INIS)

    Ohta, Kengo; Shimohira, Masashi; Murai, Taro; Nishimura, Junichi; Iwata, Hiromitsu; Ogino, Hiroyuki; Hashizume, Takuya; Shibamoto, Yuta

    2016-01-01

    The aim of this study was to describe our initial experience with a gold flexible linear fiducial marker and to evaluate the safety and technical and clinical efficacy of stereotactic body radiotherapy using this marker for malignant liver tumors. Between July 2012 and February 2015, 18 patients underwent percutaneous fiducial marker placement before stereotactic body radiotherapy for malignant liver tumors. We evaluated the technical and clinical success rates of the procedure and the associated complications. Technical success was defined as successful placement of the fiducial marker at the target site, and clinical success was defined as the completion of stereotactic body radiotherapy without the marker dropping out of position. All 18 fiducial markers were placed successfully, so the technical success rate was 100% (18/18). All 18 patients were able to undergo stereotactic body radiotherapy without marker migration. Thus, the clinical success rate was 100% (18/18). Slight pneumothorax occurred as a minor complication in one case. No major complications such as coil migration or bleeding were observed. The examined percutaneous fiducial marker was safely placed in the liver and appeared to be useful for stereotactic body radiotherapy for malignant liver tumors

  2. Catheter closure of patent foramen ovale in patients with cryptogenic cerebrovascular accidents: initial experiences in Japan.

    Science.gov (United States)

    Kijima, Yasufumi; Akagi, Teiji; Nakagawa, Koji; Taniguchi, Manabu; Ueoka, Akira; Deguchi, Kentaro; Toh, Norihisa; Oe, Hiroki; Kusano, Kengo; Sano, Shunji; Ito, Hiroshi

    2014-01-01

    Although numerous studies have shown an association between a patent foramen ovale (PFO) and cryptogenic cerebrovascular accidents (CVA), there has been no definitive control study that demonstrated the benefit of percutaneous device closure of a PFO compared to medical therapy in patients with CVA. Additionally, few clinical data exist for Japanese patients in this field. We demonstrate the initial experiences in catheter closure of a PFO as secondary prevention of CVA in Japan. Catheter closure of a PFO was attempted in 7 patients who were diagnosed with cryptogenic CVA. Mean age at the procedure was 54 ± 19 years. The presence of spontaneous interatrial right-to-left shunts was demonstrated by transesophageal contrast echocardiography without Valsalva maneuver in all of the patients. Amplatzer Cribriform device (n = 4) or Amplatzer PFO Occluder (n = 3) was used for the procedure and was successfully deployed. Device-related complications were not observed at the time of the procedure or during the follow-up period (mean period of 16 ± 9 months). Catheter closure of a PFO could be safely performed with Amplatzer Cribriform or Amplatzer PFO Occluder. This procedure may contribute to prevention of recurrent cryptogenic CVA in Japanese patients.

  3. Single-port laparoscopic approach of the left liver: initial experience.

    Science.gov (United States)

    Camps Lasa, Judith; Cugat Andorrà, Esteban; Herrero Fonollosa, Eric; García Domingo, María Isabel; Sánchez Martínez, Raquel; Vargas Pierola, Harold; Rodríguez Campos, Aurora

    2014-11-01

    New technological advances have enabled the development of single-port laparoscopic surgery. This approach began with cholecystectomy and subsequently with other abdominal surgeries. However, few publications on laparoscopic liver surgery have described the use of complete single-port access. We present our initial experience of a single-port laparoscopic hepatectomy. Between May 2012 and December 2013, 5 single-port laparoscopic hepatectomies were performed: one for benign disease and four for colorectal liver metastases. The lesions were approached through a 3-5 cm right supraumbilical incision using a single-port access device. All the lesions were located in hepatic segments II or III. Four left lateral sectorectomies and one left hepatectomy were performed. Median operative time was 135 min. No cases were converted to conventional laparoscopic or open surgery. The oral intake began at 18 h. There were no postoperative complications and no patients required blood transfusion. The median hospital stay was 3 days. The degree of satisfaction was very good in 4 cases and good in one. Patients resumed their normal daily activities at 8 days. Single-port laparoscopic hepatectomy is safe and feasible in selected cases and may reduce surgical aggression and offer better cosmetic results. Comparative studies are needed to determine the real advantages of this approach. Copyright © 2014 AEC. Published by Elsevier Espana. All rights reserved.

  4. Initial experience of two national centers in transcatheter aortic prosthesis implantation.

    Science.gov (United States)

    Lluberas, Sebastián; Abizaid, Alexandre; Siqueira, Dimytri; Ramos, Auristela; Costa, J Ribamar; Arrais, Magaly; Kambara, Antônio; Bihan, David Le; Sousa, Amanda; Sousa, J Eduardo

    2014-04-01

    Transcatheter aortic valve implantation is an effective alternative to surgical treatment of severe aortic stenosis in patients who are inoperable or at high surgical risk. To report the immediate and follow-up clinical and echocardiographic results of the initial experience of transcatheter aortic valve implantation. From 2009 June to 2013 February, 112 patients underwent transcatheter aortic valve implantation. Mean age was 82.5 ± 6.5 years, and the logistic EuroSCORE was 23.6 ± 13.5. Procedural success was 84%. After the intervention, a reduction in the mean systolic gradient was observed (pre: 54.7 ± 15.3 vs. post: 11.7 ± 4.0 mmHg; p < 0.01). Cerebrovascular accidents occurred in 3.6%, vascular complications in 19% and permanent pacemaker was required by 13% of the patients. Thirty-day mortality and at follow-up of 16 ± 11 months was 14% and 8.9% respectively. The presence of chronic obstructive pulmonary disease was the only predictor of mortality at 30 days and at follow-up. During follow up, aortic valve area and mean systolic gradient did not change significantly. Transcatheter aortic valve implantation is an effective and safe procedure for the treatment of aortic stenosis in high-surgical risk or inoperable patients. The presence of chronic obstructive pulmonary disease was the only independent predictor of mortality identified both in the first month post-intervention and at follow-up.

  5. Lateral Transorbital Endoscopic Access to the Hippocampus, Amygdala, and Entorhinal Cortex: Initial Clinical Experience.

    Science.gov (United States)

    Chen, H Isaac; Bohman, Leif-Erik; Emery, Lyndsey; Martinez-Lage, Maria; Richardson, Andrew G; Davis, Kathryn A; Pollard, John R; Litt, Brian; Gausas, Roberta E; Lucas, Timothy H

    2015-01-01

    Transorbital approaches traditionally have focused on skull base and cavernous sinus lesions medial to the globe. Lateral orbital approaches to the temporal lobe have not been widely explored despite several theoretical advantages compared to open craniotomy. Recently, we demonstrated the feasibility of the lateral transorbital technique in cadaveric specimens with endoscopic visualization. We describe our initial clinical experience with the endoscope-assisted lateral transorbital approach to lesions in the temporal lobe. Two patients with mesial temporal lobe pathology presenting with seizures underwent surgery. The use of a transpalpebral or Stallard-Wright eyebrow incision enabled access to the intraorbital compartment, and a lateral orbital wall 'keyhole' opening permitted visualization of the anterior temporal pole. This approach afforded adequate access to the surgical target and surrounding structures and was well tolerated by the patients. To the best of our knowledge, this report constitutes the first case series describing the endoscope-assisted lateral transorbital approach to the temporal lobe. We discuss the limits of exposure, the nuances of opening and closing, and comparisons to open craniotomy. Further prospective investigation of this approach is warranted for comparison to traditional approaches to the mesial temporal lobe. © 2015 S. Karger AG, Basel.

  6. Implementing a robotics curriculum at an academic general surgery training program: our initial experience.

    Science.gov (United States)

    Winder, Joshua S; Juza, Ryan M; Sasaki, Jennifer; Rogers, Ann M; Pauli, Eric M; Haluck, Randy S; Estes, Stephanie J; Lyn-Sue, Jerome R

    2016-09-01

    The robotic surgical platform is being utilized by a growing number of hospitals across the country, including academic medical centers. Training programs are tasked with teaching their residents how to utilize this technology. To this end, we have developed and implemented a robotic surgical curriculum, and share our initial experience here. Our curriculum was implemented for all General Surgical residents for the academic year 2014-2015. The curriculum consisted of online training, readings, bedside training, console simulation, participating in ten cases as bedside first assistant, and operating at the console. 20 surgical residents were included. Residents were provided the curriculum and notified the department upon completion. Bedside assistance and operative console training were completed in the operating room through a mix of biliary, foregut, and colorectal cases. During the fiscal years of 2014 and 2015, there were 164 and 263 robot-assisted surgeries performed within the General Surgery Department, respectively. All 20 residents completed the online and bedside instruction portions of the curriculum. Of the 20 residents trained, 13/20 (65 %) sat at the Surgeon console during at least one case. Utilizing this curriculum, we have trained and incorporated residents into robot-assisted cases in an efficient manner. A successful curriculum must be based on didactic learning, reading, bedside training, simulation, and trainin