WorldWideScience

Sample records for position indicator scan

  1. Is a positive L-dimer result a sufficient indication for performing a V/Q lung scan?

    International Nuclear Information System (INIS)

    Salanitri, G.C.; Kelly, M.J.; O'Donnell, M.; Kalff, V.

    2002-01-01

    Full text: At our institution there has developed a practice of referring some patients for assessment of pulmonary embolism (PE) because of a positive L-dimer test but without standard clinical indications. Therefore this study aimed to determine whether a positive L-dimer test result by itself is a sufficient indication to perform a ventilation/perfusion V/Q study. V/Q lung scan results, L-dimer test results and appropriate radiology results of 949 consecutive patients from August 2000 to October 2001 were retrospectively reviewed. Prediction of V/Q results by L-dimer results was compared with that of clinical risk factors for PE (Risk factor + or -) These factors were dyspnoea, current deep vein thrombosis (DVT), recent orthopaedic procedure or a past history of PE/DVT, Of the 949 patients in the study population, 254 patients had an L-dimer study, with 206 positive and 48 negative L-dimer results. Helical CT was performed in 8 patients with an equivocal V/Q - 4 showed PE and 4 did not. In the 27 patients with a positive L-dimer result and PE on either V-Q scan or CT, 25 (92.6%) had additional recognised major risk factors for PE. A positive L-dimer test is a poor predictor of a positive V/Q scan compared to conventional clinical indications. Thus, a positive L-dimer test result in isolation does not constitute an appropriate indication to perform a V/Q scan. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

  2. Clinical indications for Thallium-201 myocardial perfusion scanning

    International Nuclear Information System (INIS)

    Dunn, R.J.; Kelly, D.T.

    1982-01-01

    Thallium-201 myocardial perfusion scanning can assess regional myocardial perfusion non-invasively. As it is both time-consuming and expensive its use should be restricted to specific diagnostic problems. The clinical indications in known or suspected coronary artery disease are reviewed. In suspected coronary artery disease thallium scanning is most useful in patients with chest pain when the exercise ECG is uninterpretable, in men with probable angina but a negative exercise ECG, or conversely a positive exercise ECG without typical angina, and in women with probable angina and either a positive or a negative exercise ECG. In known coronary artery disease, thallium scanning may help determine the functional significance of a coronary obstruction found at angiography and may determine the site of myocardial ischaemia when multiple obstructions are present

  3. Bone scan indications in oncology

    International Nuclear Information System (INIS)

    Rocha, A.F.G. da; Marquiotti, M.

    1986-01-01

    The scintigraphic method is described and a critical analysis of its value in the research of bone metastases is presented. The method validity, the positivity of bone scan for metastases at the first examination and the preferencial distribution metastases in skeleton are related.Bone pain and the results of bone scintigram are correlated. (M.A.C.) [pt

  4. Multiple-scanning-probe tunneling microscope with nanoscale positional recognition function.

    Science.gov (United States)

    Higuchi, Seiji; Kuramochi, Hiromi; Laurent, Olivier; Komatsubara, Takashi; Machida, Shinichi; Aono, Masakazu; Obori, Kenichi; Nakayama, Tomonobu

    2010-07-01

    Over the past decade, multiple-scanning-probe microscope systems with independently controlled probes have been developed for nanoscale electrical measurements. We developed a quadruple-scanning-probe tunneling microscope (QSPTM) that can determine and control the probe position through scanning-probe imaging. The difficulty of operating multiple probes with submicrometer precision drastically increases with the number of probes. To solve problems such as determining the relative positions of the probes and avoiding of contact between the probes, we adopted sample-scanning methods to obtain four images simultaneously and developed an original control system for QSPTM operation with a function of automatic positional recognition. These improvements make the QSPTM a more practical and useful instrument since four images can now be reliably produced, and consequently the positioning of the four probes becomes easier owing to the reduced chance of accidental contact between the probes.

  5. ComPoScan: Adaptive Scanning for Efficient Concurrent Communications and Positioning with 802.11

    DEFF Research Database (Denmark)

    King, Thomas; Kjærgaard, Mikkel Baun

    2008-01-01

    and by validation in several real-world deployments. Results from the emulation show that the system can realize different trade-offs by changing parameters. Furthermore, the emulation shows that the system works independently of the environment, the network card, the signal strength measurement technology......Using 802.11 concurrently for communications and positioning is problematic, especially if location-based services (e.g., indoor navigation) are concurrently executed with real-time applications (e.g., VoIP, video conferencing). Periodical scanning for measuring the signal strength interrupts......, and number and placement of access points. We also show that ComPoScan does not harm the positioning accuracy of a positioning system. By validation in several real-world deployments, we provided evidence for that the real system works as predicted by the emulation. In addition, we provide results for Com...

  6. Excessive lateral patellar translation on axial computed tomography indicates positive patellar J sign.

    Science.gov (United States)

    Xue, Zhe; Song, Guan-Yang; Liu, Xin; Zhang, Hui; Wu, Guan; Qian, Yi; Feng, Hua

    2018-03-20

    The purpose of the study was to quantify the patellar J sign using traditional computed tomography (CT) scans. Fifty-three patients (fifty-three knees) who suffered from recurrent patellar instability were included and analyzed. The patellar J sign was evaluated pre-operatively during active knee flexion and extension. It was defined as positive when there was obvious lateral patellar translation, and negative when there was not. The CT scans were performed in all patients with full knee extension; and the parameters including bisect offset index (BOI), patellar-trochlear-groove (PTG) distance, and patellar lateral tilt angle (PLTA) were measured on the axial slices. All the three parameters were compared between the J sign-positive group (study group) and the J sign-negative group (control group). In addition, the optimal thresholds of the three CT scan parameters for predicting the positive patellar J sign were determined with receiver operating characteristic (ROC) curves, and the diagnostic values were assessed by the area under the curve (AUC). Among the fifty-three patients (fifty-three knees), thirty-seven (70%) showed obvious lateral patellar translation, which were defined as positive J sign (study group), and the remaining sixteen (30%) who showed no lateral translation were defined as negative J sign (control group). The mean values of the three CT parameters in the study group were all significantly larger compared to the control group, including BOI (121 ± 28% vs 88 ± 12%, P = 0.038), PTG distance (5.2 ± 6.6 mm vs - 4.4 ± 5.2 mm, P J sign was 97.5% (Sensitivity = 83.3%, Specificity = 87.5%). In this study, the prevalence of positive patellar J sign was 70%. The BOI measured from the axial CT scans of the knee joint can be used as an appropriate predictor to differentiate the positive J sign from the negative J sign, highlighting that the excessive lateral patellar translation on axial CT scan indicates positive

  7. A Study on the Effects of Position Change on the Liver Shape on Radioisotope Scan

    International Nuclear Information System (INIS)

    Hong, Kee Suk; Choi, Du Hyok; Yang, Young Tae; Koh, Chang Soon

    1982-01-01

    For this study, the authors obtained and examined anterior views of the liver and spleen in two different positions, upright and supine, of 39 normal subjects and 20 patients with hepatic pathology by means of 99m Tc-colloid and gamma camera. This examination confirms the following findings. In general, it is shown, left lobe of the liver in upright position becomes longer in height than in supine position, while the distance between lateral margin of the liver and that of spleen becomes father in with in supine position than in upright position. The upper margin of liver moves more downward in upright position than in supine. It is noticeable that as for 5 cases with severe chronic liver disease, there is minimal alteration of the liver shape between in two positions. The comparison of the both positions for the better liver scan shows the following findings. Prominent caudate and/or left lobe are marked in the upright position in 16 cases out of the total 59, while none is found in the supine. The false cold area in lower part of the liver disappears in 7 cases in the upright position, while only one shows the disappearance of the false cold area in the supine. Left liver margin due to close contact of spleen is blurred in 3 cases in the upright position. In total 23 cases out of 59 support that the upright position is better for the liver scan, while only 4 cases support the supine position is better. These findings support two assumptions. One is that upright view can be expected more improved resolution than supine view for liver scan. Second is that minimal change of the liver shape in both views indicate the serious abnormality in the liver.

  8. Position indicating device

    International Nuclear Information System (INIS)

    Fellchenfeld, M.M.; Connors, G.R.

    1987-01-01

    This patent describes a position indicating device for producing an indication of the position of a displaceable structure comprising: a position representing member mounted for movement in response to displacement of the structure; sensing elements spaced apart along the defined path such that each element is associated with a respective location along the defined path; means operatively coupling the elements into respective pairs of elements, having, for each pair of elements, an output producing a signal only when a single element of its respective pair is responding to the presence of the member; signal producing members each operative for producing a signal representing a predetermined logic state in response to a predetermined input signal, the number of the signal producing members being smaller than the number of the sensing elements; and circuit means operatively connecting the outputs to the signal producing members for causing a signal at each output to produce a predetermined input signal at a corresponding signal producing member and for causing a predetermined input signal to be produced at least one the signal producing member whenever a signal is present at either one of at least two of the outputs

  9. Monitoring positive mental health and its determinants in Canada: the development of the Positive Mental Health Surveillance Indicator Framework

    Directory of Open Access Journals (Sweden)

    H. Orpana

    2016-01-01

    Full Text Available Introduction: The Mental Health Strategy for Canada identified a need to enhance the collection of data on mental health in Canada. While surveillance systems on mental illness have been established, a data gap for monitoring positive mental health and its determinants was identified. The goal of this project was to develop a Positive Mental Health Surveillance Indicator Framework, to provide a picture of the state of positive mental health and its determinants in Canada. Data from this surveillance framework will be used to inform programs and policies to improve the mental health of Canadians. Methods: A literature review and environmental scan were conducted to provide the theoretical base for the framework, and to identify potential positive mental health outcomes and risk and protective factors. The Public Health Agency of Canada’s definition of positive mental health was adopted as the conceptual basis for the outcomes of this framework. After identifying a comprehensive list of risk and protective factors, mental health experts, other governmental partners and non-governmental stakeholders were consulted to prioritize these indicators. Subsequently, these groups were consulted to identify the most promising measurement approaches for each indicator. Results: A conceptual framework for surveillance of positive mental health and its determinants has been developed to contain 5 outcome indicators and 25 determinant indicators organized within 4 domains at the individual, family, community and societal level. This indicator framework addresses a data gap identified in Canada’s strategy for mental health and will be used to inform programs and policies to improve the mental health status of Canadians throughout the life course.

  10. False positive and false negative FDG-PET scans in various thoracic diseases

    International Nuclear Information System (INIS)

    Chang, Jung Min; Lee, Hyun Ju; Goo, Jin Mo; Lee, Ho Young; Lee, Jong Jin; Chung, June Key; Im, Jung Gi

    2006-01-01

    Fluorodeoxygucose (FDG)-positron emission tomography (PET) is being used more and more to differentiate benign form malignant focal lesions and it has been shown to be more efficacious than conventional chest computed tomography (CT). However, FDG is not a cancer-specific agent, and false positive findings in benign diseases have been reported. Infectious diseases (mycobacterial, fungal, bacterial infection), sarcoidosis, radiation pneumonitis and post-operative surgical conditions have shown intense uptake on PET scan. On the other hand, tumors with low glycolytic activity such as adenomas, bronchioloalveolar carcinomas, carcinoid tumors, low grade lymphomas and small sized tumors have revealed false negative findings on PET scan, Furthermore, in diseases located near the physiologic uptake sites (heart, bladder, kidney, and liver), FDG-PET should be complemented with other imaging modalities to confirm results and to minimize false negative findings. Familiarity with these false positive and negative findings will help radiologists interpret PET scans more accurately and also will help to determine the significance of the findings. In this review, we illustrate false positive and negative findings of PET scan in a variety of diseases

  11. Comparison of supine, upright, and prone positions for liver scans

    International Nuclear Information System (INIS)

    Harolds, J.A.; Brill, A.B.; Patton, J.A.; Touya, J.J.

    1983-01-01

    We compared liver scan interpretations based on anterior images obtained in the upright, prone, and supine positions. Receiver-operating-characteristic curves were generated for three well trained observers. Results showed that reading the three different views together was more accurate than the reading of any individual image. Furthermore, interpretations based on either the prone or upright view were superior to those using the supine view alone. The prone and upright views should be used more often in liver scanning

  12. Position indication apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, T

    1964-02-24

    A plurality of magnetically operated switches are spaced equally in the hollow tube of a control rod actuating mechanism. One side of each switch is connected, via a low resistance, to a corresponding tap of a low resistance voltage divider network consisting of an equivalent number of low resistance sections with the opposite side of each switch connected to a common conducting wire A. To both ends of the voltage dividing network are connected, respectively, conducting wires B and C. Wires A, B, and C are further coupled to a fuel rod position indicator comprising a voltmeter and power source external to the control rod actuating member. The control rod actuating member is adapted to slide in the hollow tube so that switches passing a position facing a magnet secured to the lower end of the actuating member are rendered closed. Hence, the position of the control rod may be read by reading the voltage off the meter.

  13. Review of design technology of control rod position indicators

    International Nuclear Information System (INIS)

    Yu, Je Yong; Huh, Hyung; Kim, Ji Ho; Kim, Jong In; Chang, Moon Hee

    1999-10-01

    An integral reactor SMART is under development at KAERI. The design characteristics of SMART are radically different from those employer in currently operating loop type water reactors in Korea. The objective of this report is to review the design technology of position indicator, and to study the various sensors which can be used in rod position indicator. Design criteria that rod position indicator should satisfy are also examined. Following position indicators are reviewed in this report. 1. Digital positioning indicator (DRPI), 2. Reed switch type position indicator (RSPT), 3. Choke sensor type position indicator, 4. Ultrasonic sensor type position indicator, 5. Comparison of each position indicator. (author)

  14. Automated SmartPrep tracker positioning in liver MRI scans

    International Nuclear Information System (INIS)

    Goto, Takao; Kabasawa, Hiroyuki

    2013-01-01

    This paper presents a new method for automated SmartPrep tracker positioning in liver MRI scans. SmartPrep is used to monitor the contrast bolus signal in order to detect the arrival time of the bolus. Accurately placing the tracker in the aorta while viewing three planar scout images is a difficult task for the operator and is an important problem from the workflow standpoint. The development of an automated SmartPrep tracker would therefore help to improve workflow in liver MRI scans. In our proposed method, the aorta is detected using AdaBoost (which is a machine learning technique) by searching around the cerebral spinal fluid (CSF) in the spinal cord. Analysis of scout scan images showed that our detection method functioned properly for a variety of axial MR images without intensity correction. A total of 234 images reconstructed from the datasets of 64 volunteers were analyzed, and the results showed that the detection error for the aorta was approximately 3 mm. (author)

  15. Adrenocortical Carcinoma: False Positive in an I-123 Metaiodobenzylguanidine Scan

    Energy Technology Data Exchange (ETDEWEB)

    Rey, Cristina Rodriguez; Candil, Aida Ortega; Galvan, Eliseo Vano; Martin, Maria Nieves Cabrera; Delgado, Jose Luis Carreras [Clinico San Carlos Hospital, Madrid (Spain)

    2016-06-15

    A 55-year-old man with a personal his history of left pheochromocytoma 2 years previously presented with an abdominal ultrasound showed a large left upper quadrant solid mass (calipers), with heterogeneous echogenicity and central cystic degeneration areas or necrosis. F-18 Fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT was performed as ACC was suspected. ACC is an uncommon malignant neoplasm of unknown cause; however, smoking and oral contraceptives may be risk factors. Patients usually present with advanced-stage disease and have poor prognosis, with a 2-year recurrence rate that ranges form 73 to 86 %. An MIBG scan was performed after injection of 185 MBq of I-123 MIBG intravenously. Single photon emission tomography (SPECT)/CT scan showed abnormal isotope accumulation in the tumor region. The patient underwent total resection of the tumor. The histology was of ACC, with areas of necrosis and cystic areas, so the result of the MIBG scan was a false positive. Authors divided false-positive MIBG studies into three categories. The first category is neuroendocrine lesions other than pheochromocytomas (tumors of the APUD series). the second category consists in adrenal lesions other than pheochromocytomas (adenomas, ACC) the reasons for this abnormal uptake are unclear. The third category consists of tracer uptake adjacent to the adrenal due to abnormalities in the route of excretion.

  16. Relevance and indications of the bone scan - an assessment

    International Nuclear Information System (INIS)

    Reinartz, P.; Buell, U.

    2002-01-01

    Due to its high sensitivity, the bone scan is one of the most frequently performed procedures in nuclear medicine. Although specificity is often criticized as its weak point, excellent results can be achieved under employment of modern acquisition techniques like SPECT imaging and multi-phased scintigraphy or under consideration of disease-specific scintigraphic patterns. Concerning the indication for a bone scan, the former rigid diagnostic plans are more and more replaced by flexible criteria or scores. This aspect as well as the growing use of CT and MRI leads to a slight decrease in the number of performed examinations. Further competition arises by the employment of positron emission tomography for the diagnosis of pathological osseous lesions using 18 F-FDG or 18 F-fluoride ion, especially in cases of malign or inflammatory disease. Although promising results have been achieved, it is doubtful whether PET will be able to replace bone scintigraphy, especially under consideration of the economic situation of the German health care system. In conclusion it can be stated that at least in the near future the conventional bone scan will remain an essential procedure within the realm of nuclear medicine. (orig.) [de

  17. Towards automatic patient positioning and scan planning using continuously moving table MR imaging.

    Science.gov (United States)

    Koken, Peter; Dries, Sebastian P M; Keupp, Jochen; Bystrov, Daniel; Pekar, Vladimir; Börnert, Peter

    2009-10-01

    A concept is proposed to simplify patient positioning and scan planning to improve ease of use and workflow in MR. After patient preparation in front of the scanner the operator selects the anatomy of interest by a single push-button action. Subsequently, the patient table is moved automatically into the scanner, while real-time 3D isotropic low-resolution continuously moving table scout scanning is performed using patient-independent MR system settings. With a real-time organ identification process running in parallel and steering the scanner, the target anatomy can be positioned fully automatically in the scanner's sensitive volume. The desired diagnostic examination of the anatomy of interest can be planned and continued immediately using the geometric information derived from the acquired 3D data. The concept was implemented and successfully tested in vivo in 12 healthy volunteers, focusing on the liver as the target anatomy. The positioning accuracy achieved was on the order of several millimeters, which turned out to be sufficient for initial planning purposes. Furthermore, the impact of nonoptimal system settings on the positioning performance, the signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) was investigated. The present work proved the basic concept of the proposed approach as an element of future scan automation. (c) 2009 Wiley-Liss, Inc.

  18. A positive 111in-pentetreotide scan in a patient with a pancreatic polypeptide secreting tumour

    International Nuclear Information System (INIS)

    Stanton, K.; Cehic, G.

    2003-01-01

    Full text: A 55-year-old male presented to our department with a known polypeptide secreting pancreatic tumour. An 111 In-pentetreotide scan (OctreoScan) was performed to determine whether the tumour expressed somatostatin receptors (SR) and thereby aid in therapy planning. 120 MBq 111 In-pentetreotide was administered intravenously. Images were acquired at 4 and 30 hours. Whole body images were acquired with spot views and tomography of the liver at 30 hours. Images showed intense uptake of the tracer in the lobular midline pancreatic mass. There was also uptake in multiple liver metastases. 111 In-pentetreotide is a synthetic somatostatin analogue and its uptake demonstrates the presence of SR on tumour cells, especially those of a neuro-endocrine nature. A 123 I Metaiodobenzylguanidine (MIBG) scan was also performed to determine whether the more widely available MIBG therapy would be appropriate for this patient. This scan was negative. The patient has received 3 cycles of chemotherapy with Streptozotocin and 5-fluorouracil. He has had a good partial response to therapy as demonstrated on CT scan. The patient is currently clinically well, his symptoms have resolved and weight stabilised. Good biochemical response to chemotherapy is indicated by halved pancreatic peptide levels. To date chemotherapy has been the mainstay of therapy for neuroendocrine tumours. Radioimmunotherapy (targeted to SR positive tumours) is currently being investigated as a therapy alternative and may be a future treatment option. Copyright (2003) The Australian and New Zealand Society of Nuclear Medicine Inc

  19. Glue-sniffing as a cause of a positive radio-isotope brain scan

    Energy Technology Data Exchange (ETDEWEB)

    Lamont, C M; Adams, F G

    1982-08-01

    Convulsions are a known complication of the acute intoxicant effects of solvent abuse. A radio-isotope brain scan done 9 months following status epilepticus secondary to toluene inhalation, in a previously normal school-boy, demonstrated several wedge-shaped areas of increased uptake, in both cerebral hemispheres, consistent with infarcts. It is worth remembering that a positive brain scan in a young person, with recent onset of epilepsy, may be due to glue-sniffing.

  20. Glue-sniffing as a cause of a positive radio-isotope brain scan

    International Nuclear Information System (INIS)

    Lamont, C.M.; Adams, F.G.

    1982-01-01

    Convulsions are a known complication of the acute intoxicant effects of solvent abuse. A radio-isotope brain scan done 9 months following status epilepticus secondary to toluene inhalation, in a previously normal school-boy, demonstrated several wedge-shaped areas if increased uptake, in both cerebral hemispheres, consistent with infarcts. It is worth remembering that a positive brain scan in a young person, with recent onset of epilepsy, may be due to glue-sniffing. (orig.)

  1. Radar Plan Position Indicator Scope

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Radar Plan Position Indicator Scope is the collection of weather radar imagery for the period prior to the beginning of the Next Generation Radar (NEXRAD) system...

  2. Laparoscopic Meckel's diverticulumectomy following positive Meckel's diverticulum scan

    International Nuclear Information System (INIS)

    Mansberg, R.; Roberts, J.M.; Tan, B.

    2002-01-01

    Full text: Laparoscopic or 'keyhole' surgery is increasingly performed to reduce morbidity and length of hospital admissions. Laparoscopic resection of a Meckel's Diverticulum has rarely been performed as the diagnosis is only rarely made prior to surgery and most patients proceed to exploratory laparotomy. A positive Meckel's scan and subsequent laparoscopic Meckel's Diverticulumectomy is presented. A 26-year-old male tourist presented with GIT bleeding following acute alcohol ingestion. He had previously been unsuccessfully investigated in England for GIT bleeding. Following a negative gastroscopy a Meckel's Diverticulum scan was performed. The study clearly demonstrated ectopic gastrin secreting mucosa in the right iliac fossa .The following day the patient went to theatre and at laparoscopy the Meckel's diverticulum was identified and resected. Histological examination confirmed the diagnosis of a Meckel's Diverticulum. The patient returned to England 2 days later. This case illustrates how a scintigraphic diagnosis can avoid exploratory surgery and result in less invasive laparoscopic surgery. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

  3. Liver-lung scan in the diagnosis of right subphrenic abscess

    International Nuclear Information System (INIS)

    Middleton, H.M. III; Patton, D.D.; Hoyumpa, A.M. Jr.; Schenker, S.

    1976-01-01

    To assess the value of liver-lung scanning in the diagnosis of right subphrenic abscess, 148 scans were reviewed against corresponding charts. Of 91 scans with adequate clinical data, overall scanning error was 19.3 percent with 14 false positive and 3 false negative scans. Among 49 scans (of the initial group of 91 studies) with presence or absence of actual pathology proved by surgery and/or autopsy, there were 3 true positive, 12 false positive, 29 true negative, and 3 false negative scans. Analysis of data indicated lower accuracy of scan interpretation than generally reported, low specificity for positive scans and high specificity for negative scans, correlation of false interpretations with atypical degrees of liver-lung separation and with scanning defects in liver and lung, and failure of rereading significantly to improve accuracy of interpretation

  4. Effect of scanning in the supine and prone positions on dilation of air-charged colon in CTVC

    International Nuclear Information System (INIS)

    Ye Jing; Chen Junkun; Zhang Zongjun; Wang Junpeng; Gao Dazhi

    2003-01-01

    Objective: To evaluate the effect of scanning in the supine and prone positions on dilation of air-charged colon in CT virtual colonoscopy (CTVC). Methods: Thirty cases underwent CTVC scanning in both the supine and prone positions immediately before colonoscopy, and the dilation of each intestine was graded. The differences of colon dilation in different positions were compared. Results: In supine and prone position, there were 26 (17.3%) and 22 (14.7%) insufficient dilating colon segments, respectively, and only 5 (3.3%) insufficient dilating colon segments in double positions. 15(50.0%) and 13(43.3%) colons dilated insufficiently in supine and prone position, respectively, and decreased to 5 (16.7%) in double positions. The dilation of rectum, sigmoid colon, and transverse colon had significant difference in different positions. Conclusion: When performing CTVC, it is highly necessary to scan in both the supine and prone positions in order to ensure the sufficient dilation of colon. In supine position, the dilation of transverse colon is better, while the dilation of rectum and sigmoid colon in prone position is superior to that in supine position

  5. An environmental scan of quality indicators in critical care.

    Science.gov (United States)

    Valiani, Sabira; Rigal, Romain; Stelfox, Henry T; Muscedere, John; Martin, Claudio M; Dodek, Peter; Lamontagne, François; Fowler, Robert; Gheshmy, Afshan; Cook, Deborah J; Forster, Alan J; Hébert, Paul C

    2017-06-21

    We performed a directed environmental scan to identify and categorize quality indicators unique to critical care that are reported by key stakeholder organizations. We convened a panel of experts ( n = 9) to identify key organizations that are focused on quality improvement or critical care, and reviewed their online publications and website content for quality indicators. We identified quality indicators specific to the care of critically ill adult patients and then categorized them according to the Donabedian and the Institute of Medicine frameworks. We also noted the organizations' rationale for selecting these indicators and their reported evidence base. From 28 targeted organizations, we identified 222 quality indicators, 127 of which were unique. Of the 127 indicators, 63 (32.5%) were safety indicators and 61 (31.4%) were effectiveness indicators. The rationale for selecting quality indicators was supported by consensus for 58 (26.1%) of the 222 indicators and by published research evidence for 45 (20.3%); for 119 indicators (53.6%), the rationale was not reported or the reader was referred to other organizations' reports. Of the 127 unique quality indicators, 27 (21.2%) were accompanied by a formal grading of evidence, whereas for 52 (40.9%), no reference to evidence was provided. There are many quality indicators related to critical care that are available in the public domain. However, owing to a paucity of rationale for selection, supporting evidence and results of implementation, it is not clear which indicators should be adopted for use. Copyright 2017, Joule Inc. or its licensors.

  6. Bone scanning in severe external otitis

    International Nuclear Information System (INIS)

    Levin, W.J.; Shary, J.H. III; Nichols, L.T.; Lucente, F.E.

    1986-01-01

    Technetium99 Methylene Diphosphate bone scanning has been considered an early valuable tool to diagnose necrotizing progressive malignant external otitis. However, to our knowledge, no formal studies have actually compared bone scans of otherwise young, healthy patients with severe external otitis to scans of patients with clinical presentation of malignant external otitis. Twelve patients with only severe external otitis were studied with Technetium99 Diphosphate and were compared to known cases of malignant otitis. All scans were evaluated by two neuroradiologists with no prior knowledge of the clinical status of the patients. Nine of the 12 patients had positive bone scans with many scans resembling those reported with malignant external otitis. Interestingly, there was no consistent correlation between the severity of clinical presentation and the amount of Technetium uptake. These findings suggest that a positive bone scan alone should not be interpreted as indicative of malignant external otitis

  7. Bench calibration of INDUS-2 beam position indicators

    International Nuclear Information System (INIS)

    Tyagi, Y.; Banerji, Anil; Kotaiah, S.

    2005-01-01

    A third generation synchrotron radiation source of energy 2.5 GeV named INDUS-2 at Centre for Advanced Technology (C.A.T), Indore (M.P) is in the advanced stage of construction. Accurate determination and correction of beam closed orbit in INDUS-2 machine within 100 of microns is a very desirable goal. Bench based calibration of Beam Position Indicators (BPI) play a very important and useful role during initial commissioning of electron machines. To precisely measure transverse position of electron beam in the Indus-2 storage ring, 56 Beam Position Indicators (BPI) will be installed in INDUS-2 machine. Out of 56 Beam Position Indicators 40 are of individual type whereas 16 are integrated with dipole vacuum chamber. The Beam Position Indicators are required to be calibrated before they can be installed. The calibration is done to determine electrical offset with respect to defined mechanical centre, to determine displacement sensitivities as well as non linearity's of BPI. Ideally when beam passes through the geometrical center of BPI's, all electrodes should have same signal strength. However due to different capacitance of electrodes and offset and drift in electronics, the electrical centre (mechanical x, y where all electrodes shows same signal strength) differs from mechanical centre of BPI. A fully automatic calibration system has been developed to carry out the calibration of Beam Position Indicators. A calibration software has been developed which has necessary utilities to process and display calibration data and results. This paper describes the calibration results of Indus-2 BPM. (author)

  8. A two-dimensional position sensitive gas chamber with scanned charge transfer readout

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, F. E-mail: faustgr@usc.es; Iglesias, A.; Lobato, R.; Mosquera, J.; Pardo, J.; Pena, J.; Pazos, A.; Pombar, M.; Rodriguez, A

    2003-10-21

    We have constructed and tested a two-dimensional position sensitive parallel-plate gas ionization chamber with scanned charge transfer readout. The scan readout method described here is based on the development of a new position-dependent charge transfer technique. It has been implemented by using gate strips perpendicularly oriented to the collector strips. This solution reduces considerably the number of electronic readout channels needed to cover large detector areas. The use of a 25 {mu}m thick kapton etched circuit allows high charge transfer efficiency with a low gating voltage, consequently needing a very simple commutating circuit. The present prototype covers 8x8 cm{sup 2} with a pixel size of 1.27x1.27 mm{sup 2}. Depending on the intended use and beam characteristics a smaller effective pixel is feasible and larger active areas are possible. This detector can be used for X-ray or other continuous beam intensity profile monitoring.

  9. A two-dimensional position sensitive gas chamber with scanned charge transfer readout

    International Nuclear Information System (INIS)

    Gomez, F.; Iglesias, A.; Lobato, R.; Mosquera, J.; Pardo, J.; Pena, J.; Pazos, A.; Pombar, M.; Rodriguez, A.

    2003-01-01

    We have constructed and tested a two-dimensional position sensitive parallel-plate gas ionization chamber with scanned charge transfer readout. The scan readout method described here is based on the development of a new position-dependent charge transfer technique. It has been implemented by using gate strips perpendicularly oriented to the collector strips. This solution reduces considerably the number of electronic readout channels needed to cover large detector areas. The use of a 25 μm thick kapton etched circuit allows high charge transfer efficiency with a low gating voltage, consequently needing a very simple commutating circuit. The present prototype covers 8x8 cm 2 with a pixel size of 1.27x1.27 mm 2 . Depending on the intended use and beam characteristics a smaller effective pixel is feasible and larger active areas are possible. This detector can be used for X-ray or other continuous beam intensity profile monitoring

  10. Prostate-Specific Antigen and Prostate-Specific Antigen Velocity as Threshold Indicators in 11C-Acetate PET/CTAC Scanning for Prostate Cancer Recurrence

    Science.gov (United States)

    Dusing, Reginald W.; Peng, Warner; Lai, Sue-Min; Grado, Gordon L.; Holzbeierlein, Jeffrey M.; Thrasher, J. Brantley; Hill, Jacqueline; Van Veldhuizen, Peter J.

    2014-01-01

    Purpose The aim of this study was to identify which patient characteristics are associated with the highest likelihood of positive findings on 11C-acetate PET/computed tomography attenuation correction (CTAC) (PET/CTAC) scan when imaging for recurrent prostate cancer. Methods From 2007 to 2011, 250 11C-acetate PET/CTAC scans were performed at a single institution on patients with prostate cancer recurrence after surgery, brachytherapy, or external beam radiation. Of these patients, 120 met our inclusion criteria. Logistic regression analysis was used to examine the relationship between predictability of positive findings and patients’ characteristics, such as prostate-specific antigen (PSA) level at the time of scan, PSA kinetics, Gleason score, staging, and type of treatment before scan. Results In total, 68.3% of the 120 11C-acetate PET/CTAC scans were positive. The percentage of positive scans and PSA at the time of scanning and PSA velocity (PSAV) had positive correlations. The putative sensitivity and specificity were 86.6% and 65.8%, respectively, when a PSA level greater than 1.24 ng/mL was used as the threshold for scanning. The putative sensitivity and specificity were 74% and 75%, respectively, when a PSAV level greater than 1.32 ng/mL/y was used as the threshold. No significant associations were found between scan positivity and age, PSA doubling time, Gleason score, staging, or type of treatment before scanning. Conclusions This retrospective study suggests that threshold models of PSA greater than 1.24 ng/mL or PSAV greater than 1.32 ng/mL per year are independent predictors of positive findings in 11C-acetate PET/CTAC imaging of recurrent prostate cancer. PMID:25036021

  11. Development of Seismic Resistance Position Indicator for the Integral Reactor

    International Nuclear Information System (INIS)

    Yu, Je-Yong; Huh, Hyung; Choi, Myoung-Hwan; Kim, Ji-Ho; Sohn, Dong-Seong

    2008-01-01

    The present paper is related to position sensing means and more particularly, to a magnetic position sensor using a permanent magnet and a compact arrangement of reed switches in a nuclear power plant. The reed switch position transmitter (RSPT) is used as a position indicator for the control rod in commercial nuclear power plants made by ABB-CE. But this position indicator has some problems when directly adopting it to the integral reactor. Its indicating resolution (1-1/2 inch (38.1mm)) is suitable to measure the position of a control rod which is driven by a motor having steps of 3/4 inch (19.05mm). But the Control Element Drive Mechanism (CEDM) for the integral reactor is designed to raise and lower the control rod in steps of 2mm in order to satisfy the design features of the integral reactor which are the soluble boron free operation and the use of a nuclear heating for the reactor start-up. These design features require a CEDM for the integral reactor to have a fine-step movement for a fine reactivity control. Therefore the resolution of the position indicator for the integral reactor should be achieved to sense the position of the control rod more precisely than that of the RSPT of the ABB-CE. This paper adopts seismic resistance reed switches to the position indicator in order to reduce the damages or impacts during the handling of the position indicator and earthquake. The control rod position indicator having a seismic resistance characteristic for the integral reactor was developed on the basis of the RSPT technology identified through the survey

  12. Development of a Nomogram Model Predicting Current Bone Scan Positivity in Patients Treated with Androgen-Deprivation Therapy for Prostate Cancer

    Science.gov (United States)

    Gotto, Geoffrey T.; Yu, Changhong; Bernstein, Melanie; Eastham, James A.; Kattan, Michael W.

    2014-01-01

    Purpose: To develop a nomogram predictive of current bone scan positivity in patients receiving androgen-deprivation therapy (ADT) for advanced prostate cancer; to augment clinical judgment and highlight patients in need of additional imaging investigations. Materials and methods: A retrospective chart review of bone scan records (conventional 99mTc-scintigraphy) of 1,293 patients who received ADT at the Memorial Sloan-Kettering Cancer Center from 2000 to 2011. Multivariable logistic regression analysis was used to identify variables suitable for inclusion in the nomogram. The probability of current bone scan positivity was determined using these variables and the predictive accuracy of the nomogram was quantified by concordance index. Results: In total, 2,681 bone scan records were analyzed and 636 patients had a positive result. Overall, the median pre-scan prostate-specific antigen (PSA) level was 2.4 ng/ml; median PSA doubling time (PSADT) was 5.8 months. At the time of a positive scan, median PSA level was 8.2 ng/ml; 53% of patients had PSA <10 ng/ml; median PSADT was 4.0 months. Five variables were included in the nomogram: number of previous negative bone scans after initiating ADT, PSA level, Gleason grade sum, and history of radical prostatectomy and radiotherapy. A concordance index value of 0.721 was calculated for the nomogram. This was a retrospective study based on limited data in patients treated in a large cancer center who underwent conventional 99mTc bone scans, which themselves have inherent limitations. Conclusion: This is the first nomogram to predict current bone scan positivity in ADT-treated prostate cancer patients, providing high predictive accuracy. PMID:25386410

  13. Development of a nomogram model predicting current bone scan positivity in patients treated with androgen-deprivation therapy for prostate cancer

    Directory of Open Access Journals (Sweden)

    Michael eKattan

    2014-10-01

    Full Text Available Purpose: To develop a nomogram predictive of current bone scan positivity in patients receiving androgen-deprivation therapy (ADT for advanced prostate cancer; to augment clinical judgment and highlight patients in need of additional imaging investigations.Materials and Methods: A retrospective chart review of bone scan records (conventional 99mTc-scintigraphy of 1,293 patients who received ADT at the Memorial Sloan-Kettering Cancer Center from 2000 to 2011. Multivariable logistic regression analysis was used to identify variables suitable for inclusion in the nomogram. The probability of current bone scan positivity was determined using these variables and the predictive accuracy of the nomogram was quantified by concordance index.Results: In total, 2,681 bone scan records were analyzed and 636 patients had a positive result. Overall, the median pre-scan prostate-specific antigen (PSA level was 2.4 ng/ml; median PSA doubling time (PSADT was 5.8 months. At the time of a positive scan, median PSA level was 8.2 ng/ml; 53% of patients had PSA <10 ng/ml; median PSADT was 4.0 months. Five variables were included in the nomogram: number of previous negative bone scans after initiating ADT, PSA level, Gleason grade sum, and history of radical prostatectomy and radiotherapy. A concordance index value of 0.721 was calculated for the nomogram. This was a retrospective study based on limited data in patients treated in a large cancer centre who underwent conventional 99mTc bone scans, which themselves have inherent limitations. Conclusions: This is the first nomogram to predict current bone scan positivity in ADT-treated prostate cancer patients, providing high predictive accuracy.

  14. Fluorodeoxyglucose-positron emission tomography scan-positive recurrent papillary thyroid cancer and the prognosis and implications for surgical management

    Directory of Open Access Journals (Sweden)

    Schreinemakers Jennifer MJ

    2012-09-01

    Full Text Available Abstract Background To compare outcomes for patients with recurrent or persistent papillary thyroid cancer (PTC who had metastatic tumors that were fluorodeoxyglucose-positron emission tomography (FDG-PET positive or negative, and to determine whether the FDG-PET scan findings changed the outcome of medical and surgical management. Methods From a prospective thyroid cancer database, we retrospectively identified patients with recurrent or persistent PTC and reviewed data on demographics, initial stage, location and extent of persistent or recurrent disease, clinical management, disease-free survival and outcome. We further identified subsets of patients who had an FDG-PET scan or an FDG-PET/CT scan and whole-body radioactive iodine scans and categorized them by whether they had one or more FDG-PET-avid (PET-positive lesions or PET-negative lesions. The medical and surgical treatments and outcome of these patients were compared. Results Between 1984 and 2008, 41 of 141 patients who had recurrent or persistent PTC underwent FDG-PET (n = 11 or FDG-PET/CT scans (n = 30; 22 patients (54% had one or more PET-positive lesion(s, 17 (41% had PET-negative lesions, and two had indeterminate lesions. Most PET-positive lesions were located in the neck (55%. Patients who had a PET-positive lesion had a significantly higher TNM stage (P = 0.01, higher age (P = 0.03, and higher thyroglobulin (P = 0.024. Only patients who had PET-positive lesions died (5/22 vs. 0/17 for PET-negative lesions; P = 0.04. In two of the seven patients who underwent surgical resection of their PET-positive lesions, loco-regional control was obtained without evidence of residual disease. Conclusion Patients with recurrent or persistent PTC and FDG-PET-positive lesions have a worse prognosis. In some patients loco-regional control can be obtained without evidence of residual disease by reoperation if the lesion is localized in the neck or mediastinum.

  15. Heart position variability during voluntary moderate deep inspiration breath-hold radiotherapy for breast cancer determined by repeat CBCT scans.

    Science.gov (United States)

    van Haaren, Paul; Claassen-Janssen, Fiere; van de Sande, Ingrid; Boersma, Liesbeth; van der Sangen, Maurice; Hurkmans, Coen

    2017-08-01

    Voluntary moderate deep inspiration breath hold (vmDIBH) in left-sided breast cancer radiotherapy reduces cardiac dose. The aim of this study was to investigate heart position variability in vmDIBH using CBCT and to compare this variability with differences in heart position between vmDIBH and free breathing (FB). For 50 patients initial heart position with respect to the field edge (HP-FE) was measured on a vmDIBH planning CT scan. Breath-hold was monitored using an in-house developed vertical plastic stick. On pre-treatment CBCT scans, heart position variability with respect to the field edge (Δ HP-FE ) was measured, reflecting heart position variability when using an offline correction protocol. After registering the CBCT scan to the planning CT, heart position variability with respect to the chest wall (Δ HP-CW ) was measured, reflecting heart position variability when using an online correction protocol. As a control group, vmDIBH and FB computed tomography (CT) scans were acquired for 30 patients and registering both scans on the chest wall. For 34 out of 50 patients, the average HP-FE and HP-CW increased over the treatment course in comparison to the planning CT. Averaged over all patients and all treatment fractions, the Δ HP-FE and the Δ HP-CW was 0.8±4.2mm (range -9.4-+10.6mm) and 1.0±4.4mm (range -8.3-+10.4mm) respectively. The average gain in heart to chest wall distance was 11.8±4.6mm when using vmDIBH instead of FB. In conclusion, substantial variability in heart position using vmDIBH was observed during the treatment course. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  16. A digital position-indication system for control rods

    International Nuclear Information System (INIS)

    Nishizawa, Yukio; Hayakawa, Toshifumi

    1979-01-01

    Systems that detect and indicate the position of the control rods that regulate the thermal output of a nuclear reactor play a particularly important role in monitoring its operational status. Conventionally, control rod position indication in pressurized water reactors has been of the analog type, utilizing the principle of the differential transformer. The present digital system was developed with the objective of achieving greater stability, greater accuracy, and higher reliability. The article gives a general description of the system and describes its advantages. (author)

  17. False positive indium-111 white blood cell scan in a closed clavicle fracture

    International Nuclear Information System (INIS)

    Friedman, R.J.; Gordon, L.

    1988-01-01

    Aggressive treatment of the multiply injured patient often requires early fixation of many fractures, some of which may be open. Often, patients develop postoperative fevers requiring a thorough workup to rule out infection. Recently, indium-111 white blood cell (WBC) imaging has become a valuable adjunct in the diagnosis of acute infection. The patient described had a simple, closed clavicle fracture with markedly increased activity on an indium-111 WBC scan obtained for fever workup. This subsequently proved to be a normal, healing, noninfected fracture by other diagnostic techniques. Noninfected, simple closed fractures should be added to the list of causes for a false-positive indium-111 WBC scan

  18. 21 CFR 872.1850 - Lead-lined position indicator.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1850 Lead-lined position indicator. (a... dental x-ray tube and intended to aid in positioning the tube, to prevent the misfocusing of the x-rays by absorbing divergent radiation, and to prevent leakage of radiation. (b) Classification. Class I...

  19. Digital, electromagnetic rod position indicator with compensation

    International Nuclear Information System (INIS)

    Feilchenfeld, M.M.; Geis, C.G.

    1985-01-01

    A digital rod position indicator having discrete coils L 0 , L 1 , L 2 ..... spaced along the travel path of an elongate magnetically permeable member stores in digital form compensation signals for automatically adjusting the location relative to the coils at which a digital output signal representative of the position of the end of the elongate member transitions from one code to the next. The appropriate compensation signal is addressed using the digital output signal and a correction factor which takes into account the direction of movement including reversals. Reference is made to the positioning of the control rods in a pressurized water reactor. (author)

  20. An Autonomous Ultra-Wide Band-Based Attitude and Position Determination Technique for Indoor Mobile Laser Scanning

    Directory of Open Access Journals (Sweden)

    Lawrence Lau

    2018-04-01

    Full Text Available Mobile laser scanning (MLS has been widely used in three-dimensional (3D city modelling data collection, such as Google cars for Google Map/Earth. Building Information Modelling (BIM has recently emerged and become prominent. 3D models of buildings are essential for BIM. Static laser scanning is usually used to generate 3D models for BIM, but this method is inefficient if a building is very large, or it has many turns and narrow corridors. This paper proposes using MLS for BIM 3D data collection. The positions and attitudes of the mobile laser scanner are important for the correct georeferencing of the 3D models. This paper proposes using three high-precision ultra-wide band (UWB tags to determine the positions and attitudes of the mobile laser scanner. The accuracy of UWB-based MLS 3D models is assessed by comparing the coordinates of target points, as measured by static laser scanning and a total station survey.

  1. Indications for direct multidirectional or multiplanar electronic reconstructions in CT-scanning of the head

    International Nuclear Information System (INIS)

    Kaiser, M.C.; Veiga-Pires, J.A.; Gooskens, R.; Troost, J.

    1982-01-01

    The authors set out to indicate the optimal applications at minimum radiation penalty of both direct multidirectional and multiplanar electronic reconstruction modes in CT-scanning of the head by means of two illustrative case reports of midline congenital tumours. (orig.)

  2. 46 CFR 169.555 - Emergency position indicating radio beacon (EPIRB).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Emergency position indicating radio beacon (EPIRB). 169.555 Section 169.555 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS... Emergency position indicating radio beacon (EPIRB). (a) Each vessel certificated for exposed waters must...

  3. 46 CFR 169.744 - Emergency position indicating radio beacon (EPIRB).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Emergency position indicating radio beacon (EPIRB). 169.744 Section 169.744 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS... position indicating radio beacon (EPIRB). Each EPIRB must be marked with the vessel's name. ...

  4. Examination of CT-AEC when the positioning changes after planning of CT scanning

    International Nuclear Information System (INIS)

    Esaki, Tooru; Yamazaki, Shoichi

    2009-01-01

    CT-automatic exposure control (AEC) controls tube current collecting information of the subject from positioning shooting. Because of this, we consider that CT-AEC does not get to operate properly if the body position of the test subject changes after the positioning shooting. However, we often experience in body positions of test subjects after the positioning shooting. In cases like this, we measured by using a phantom again to see how they affect the tube current value and standard deviation (SD) value comparing them to the normal scan where a body position does not change. As a result of the measurement, there was an impact on CT-AEC that optimization of tube current becomes insufficient if the body position of a test subject changes. As the image quality is deteriorated and radiation exposure increases because of this, taking positioning shooting again is required on the part of users and it's desirable on the part of manufacturers to develop CT-AEC that can be controlled with high accuracy. (author)

  5. The abdominal technetium scan (a decade of experience)

    International Nuclear Information System (INIS)

    Cooney, D.R.; Duszynski, D.O.; Camboa, E.; Karp, M.P.; Jewett, T.C. Jr.

    1982-01-01

    Out of 270 children with gastrointestinal symptoms, the indications for technetium scanning were: gastrointestinal tract bleeding (165 patients), abdominal pain (99 patients) and a history of intussusception (6 patients). Thirty children had abnormal findings, while the remaining 240 patients had normal scans. Four of the 30 children with positive scans were not explored, while the others underwent laparotomy. Of the 26 operated patients, 12 (46%) had a Meckel's diverticulum. Nine patients (34%) had other pathologic lesions that were detected by the scan. Five had true false positives as no pathologic lesions were found. Of the 240 children with negative scans, 19 were eventually explored because of persistent symptoms or clinical findings. Two of these had a Meckel's diverticulum. Eleven had a negative exploration while six had other surgical lesions. Technitium scan should reliably detect around 80%-90% of Meckel's diverticula. It will also accurately exclude the diagnosis of Meckel's diverticulum in over 90% of patients

  6. Consensus-based identification of factors related to false-positives in ultrasound scanning of synovitis and tenosynovitis.

    Science.gov (United States)

    Ikeda, Kei; Narita, Akihiro; Ogasawara, Michihiro; Ohno, Shigeru; Kawahito, Yutaka; Kawakami, Atsushi; Ito, Hiromu; Matsushita, Isao; Suzuki, Takeshi; Misaki, Kenta; Ogura, Takehisa; Kamishima, Tamotsu; Seto, Yohei; Nakahara, Ryuichi; Kaneko, Atsushi; Nakamura, Takayuki; Henmi, Mihoko; Fukae, Jun; Nishida, Keiichiro; Sumida, Takayuki; Koike, Takao

    2016-01-01

    We aimed to identify causes of false-positives in ultrasound scanning of synovial/tenosynovial/bursal inflammation and provide corresponding imaging examples. We first performed systematic literature review to identify previously reported causes of false-positives. We next determined causes of false-positives and corresponding example images for educational material through Delphi exercises and discussion by 15 experts who were an instructor and/or a lecturer in the 2013 advanced course for musculoskeletal ultrasound organized by Japan College of Rheumatology Committee for the Standardization of Musculoskeletal Ultrasonography. Systematic literature review identified 11 articles relevant to sonographic false-positives of synovial/tenosynovial inflammation. Based on these studies, 21 candidate causes of false-positives were identified in the consensus meeting. Of these items, 11 achieved a predefined consensus (≥ 80%) in Delphi exercise and were classified as follows: (I) Gray-scale assessment [(A) non-specific synovial findings and (B) normal anatomical structures which can mimic synovial lesions due to either their low echogenicity or anisotropy]; (II) Doppler assessment [(A) Intra-articular normal vessels and (B) reverberation)]. Twenty-four corresponding examples with 49 still and 23 video images also achieved consensus. Our study provides a set of representative images that can help sonographers to understand false-positives in ultrasound scanning of synovitis and tenosynovitis.

  7. Value of 201Tl imaging in predicting therapeutic 131I uptake in patients with thyroglobulin-positive but 131I scan-negative differentiated thyroid carcinoma

    International Nuclear Information System (INIS)

    Conlu, R.A.O.; Obaldo, J.M.

    2004-01-01

    Background: Serum thyroglobulin assay and 131Iodine (1311) whole body scan are considered complementary in detecting malignant thyroid tissue or metastases. A large number of patients, however, are encountered presenting with scan-negative, thyroglobulin-positive differentiated thyroid carcinoma posing a dilemma in therapeutic management. One of the first alternative scanning agents to be employed is 201Thallium (201Tl). Recent studies have demonstrated its usefulness in identifying lesions that are not visualized with traditional 131I whole body scan. It is not clear, however, whether 201Tl scan helps in the decision-making for subsequent 131I therapy. This study was conducted to determine if 201Tl scan can predict therapeutic 131I uptake and to define the clinical role of 201Tl scanning in these patients. Methods and results: A total of 12 patients (20-63 y/o), 5 males and 7 females, underwent surgery for differentiated thyroid cancer and all had serum thyroglobulin values above 10 ng/ml and normal TPO autoantibodies. Pre-therapy 131I scan using 111 MBq (3mCi) of 131I were obtained. As required for inclusion, all patients had negative pre-therapy scan and negative TPO autoantibody results and underwent 20lTl scanning within 3 weeks. All patients were given 131I therapy (3.7-5.5 GBq or 100-150 mCi) between one to two months after 201Tl scanning. Within a week after therapy, all patients underwent whole body 1311 scanning. 201Tl imaging demonstrated thyroid remnants in 9 out of 12 patients having positive 201Tl scan but negative pre-therapy 1311 scan. However, only 2 of the positive 201Tl scans showed 131I uptake post-therapy (positive predictive value of 20%). None of the subjects presented with a negative 201Tl scan and a positive post-therapy 131I scan. Conclusion: Our study suggests that evidence of remnants or metastases on 201Tl scanning may be an inappropriate basis for the decision to proceed with 131I therapy. The role of 20lTl imaging in this subset of

  8. Pattern of Prostate-Specific Antigen (PSA) Failure Dictates the Probability of a Positive Bone Scan in Patients With an Increasing PSA After Radical Prostatectomy

    Science.gov (United States)

    Dotan, Zohar A.; Bianco, Fernando J.; Rabbani, Farhang; Eastham, James A.; Fearn, Paul; Scher, Howard I.; Kelly, Kevin W.; Chen, Hui-Ni; Schöder, Heiko; Hricak, Hedvig; Scardino, Peter T.; Kattan, Michael W.

    2007-01-01

    Purpose Physicians often order periodic bone scans (BS) to check for metastases in patients with an increasing prostate-specific antigen (PSA; biochemical recurrence [BCR]) after radical prostatectomy (RP), but most scans are negative. We studied patient characteristics to build a predictive model for a positive scan. Patients and Methods From our prostate cancer database we identified all patients with detectable PSA after RP. We analyzed the following features at the time of each bone scan for association with a positive BS: preoperative PSA, time to BCR, pathologic findings of the RP, PSA before the BS (trigger PSA), PSA kinetics (PSA doubling time, PSA slope, and PSA velocity), and time from BCR to BS. The results were incorporated into a predictive model. Results There were 414 BS performed in 239 patients with BCR and no history of androgen deprivation therapy. Only 60 (14.5%) were positive for metastases. In univariate analysis, preoperative PSA (P = .04), seminal vesicle invasion (P = .02), PSA velocity (P < .001), and trigger PSA (P < .001) predicted a positive BS. In multivariate analysis, only PSA slope (odds ratio [OR], 2.71; P = .03), PSA velocity (OR, 0.93; P = .003), and trigger PSA (OR, 1.022; P < .001) predicted a positive BS. A nomogram for predicting the bone scan result was constructed with an overfit-corrected concordance index of 0.93. Conclusion Trigger PSA, PSA velocity, and slope were associated with a positive BS. A highly discriminating nomogram can be used to select patients according to their risk for a positive scan. Omitting scans in low-risk patients could reduce substantially the number of scans ordered. PMID:15774789

  9. Measurement of position and profile of undulator radiation in Indus-2 using scanning wire monitor

    International Nuclear Information System (INIS)

    Kant, Chander; Lal, Sohan; Raghuwanshi, V.K.; Prasad, Vijendra

    2015-01-01

    Two planar undulators (U1 and U2) for Atomic Molecular Spectroscopy (AMOS) beamline and Angle Resolved Photoelectron Spectroscopy (ARPES) beamline have been installed in Indus-2. The U1 undulator is designed to produce photons in the energy range of 6 eV to 250 eV and U2 undulator is designed to produce photons in the energy range of 30 eV to 600 eV. In order to measure the position and vertical profile of photon beams emitted from these undulators, one scanning wire monitor has been installed in each beamline front end. In these scanning wire monitors, a gold coated tungsten wire of 100 μm thickness, stretched between a fork shaped alumina ceramic holder, is scanned vertically perpendicular to the direction of propagation of photon beam by using a precisely controlled stepper motor. The photo-electron current generated in the wire is measured by an electrometer. A graphical user interface has been developed which facilitates the scanning as per the given range, plots the graphs and stores the scanned data in Excel file. This paper describes our experience and usefulness of these wire monitors during commissioning of planar undulators in Indus-2. (author)

  10. Registration accuracy and image quality of time averaged mid-position CT scans for liver SBRT

    NARCIS (Netherlands)

    Kruis, Matthijs F.; van de Kamer, Jeroen B.; Sonke, Jan-Jakob; Jansen, Edwin P. M.; van Herk, Marcel

    2013-01-01

    The purpose was to validate the accuracy of motion models derived from deformable registration from four-dimensional computed tomography (4DCT) and breath-hold contrast enhanced computed tomography (BHCCT) scans for liver SBRT. Additionally, the image quality of the time averaged mid-position (MidP)

  11. Economic evaluation of reprocessing - Indicative Belgian position

    International Nuclear Information System (INIS)

    1979-05-01

    This paper, which also appears as an Appendix to the final Working Group 4 report, forms part of the overall economic evaluation of reprocessing. The indicative national position and illustrative ''phase diagram'' for Belgium is presented. Other factors which influence the Belgian viewpoint and which are not included on the phase diagram are given

  12. Bone scans in nasopharyngeal carcinoma: local experience

    International Nuclear Information System (INIS)

    Tiong, S.

    2004-01-01

    correct in the true positive group of patients but uncertain in the false negative group.The incidence of positive bone scans appears to suggest relatively higher rate of bone metastasis in the patients of advanced stages. Conclusion: The number of present series of NPC patients studied and the relative incidences of true and false positives are small. However the findings indicate that bone scans using TC99 is a good screening test as it helps Clinicians realize the sites of likely metastasis and decision for further confirmatory X ray imagings; this is especially true in the case of treated patients.It is hoped that the patient sample size will be increased in the future for improved assessment and evaluation. (authors)

  13. Tri-code inductance control rod position indicator with several multi-coding-bars

    International Nuclear Information System (INIS)

    Shi Jibin; Jiang Yueyuan; Wang Wenran

    2004-01-01

    A control rod position indicator named as tri-code inductance control rod position indicator with multi-coding-bars, which possesses simple structure, reliable operation and high precision, is developed. The detector of the indicator is composed of K coils, a compensatory coil and K coding bars. Each coding bar consists of several sections of strong magnetic cores, several sections of weak magnetic cores and several sections of non-magnetic portions. As the control rod is withdrawn, the coding bars move in the center of the coils respectively, while the constant alternating current passes the coils and makes them to create inductance alternating voltage signals. The outputs of the coils are picked and processed, and the tri-codes indicating rod position can be gotten. Moreover, the coding principle of the detector and its related structure are introduced. The analysis shows that the indicator owns more advantage over the coils-coding rod position indicator, so it can meet the demands of the rod position indicating in nuclear heating reactor (NHR). (authors)

  14. Preliminary performance test of control rod position indicator for ballscrew type CEDM

    International Nuclear Information System (INIS)

    Yoo, J. Y.; Kim, J. H.; Hu, H.; Lee, J. S.; Kim, J. I.

    2003-01-01

    The reliability and accuracy of the information on control rod position are very important to the reactor safety and the design of the core protection system. A survey on the RSPT(Reed Switch Position Transmitter) type control rod position indication system and its actual implementation in the exiting nuclear power plants in Korea was performed first. The prototype of control rod position indicator having the high performance for the ballscrew type CEDM was developed on the basis of RSPT technology identified through the survey. The characteristics of control rod position indicator was defined and documented through design procedure and preliminary performance test

  15. Bone scan and joint scan of hands and feet in rheumatoid arthritis

    International Nuclear Information System (INIS)

    Carpentier, N.; Verbeke, S.; Perdrisot, R.; Grilo, R.M.; Quenesson, E.; Bonnet, C.; Vergne, P.; Treves, R.; Bertin, P.; Boutros-Toni, F.

    2000-01-01

    The aim of this study was to determine the ability of joint scan and bone scan of hands and feet, in patients with rheumatoid arthritis, to localize the altered joints. The sensitivity, the specificity, the positive predictive value (PPV) and the negative predictive value (NPV) of joint scan were determined in comparison with clinical joint assessment. Fifteen patients (780 joints) were clinically examined (pain and synovitis); during the same day, a bone scan and a joint scan were realized by oxidronate 99m Tc intravenous injection. Patients were scanned 5 minutes (tissual time, T t ) and 3 hours 1/4 (bone time, T 0 ) after the administration. The uptake of the bi-phosphonate was evaluated with a qualitative method using a grey scale. The uptake of 99m Tc oxidronate was quantitated using an extra-articular region of interest. The sensitivity, specificity, PPV and NPV of the scan at Tt were 46%, 96%, 85% et 78%. The same parameters were 75%, 66%, 53% and 84% for the scan realized at T 0 . The joint scan has showed 22% of false positive. These false positives could be a consequence of an earlier detection of joint alterations by scan. The joint scan should forecast the evolution of joints in patients with rheumatoid arthritis. (author)

  16. Characterization of Line Nanopatterns on Positive Photoresist Produced by Scanning Near-Field Optical Microscope

    Directory of Open Access Journals (Sweden)

    Sadegh Mehdi Aghaei

    2015-01-01

    Full Text Available Line nanopatterns are produced on the positive photoresist by scanning near-field optical microscope (SNOM. A laser diode with a wavelength of 450 nm and a power of 250 mW as the light source and an aluminum coated nanoprobe with a 70 nm aperture at the tip apex have been employed. A neutral density filter has been used to control the exposure power of the photoresist. It is found that the changes induced by light in the photoresist can be detected by in situ shear force microscopy (ShFM, before the development of the photoresist. Scanning electron microscope (SEM images of the developed photoresist have been used to optimize the scanning speed and the power required for exposure, in order to minimize the final line width. It is shown that nanometric lines with a minimum width of 33 nm can be achieved with a scanning speed of 75 µm/s and a laser power of 113 mW. It is also revealed that the overexposure of the photoresist by continuous wave laser generated heat can be prevented by means of proper photoresist selection. In addition, the effects of multiple exposures of nanopatterns on their width and depth are investigated.

  17. New approach for control rod position indication system for light water power reactor

    International Nuclear Information System (INIS)

    Bahuguna, Sushil; Dhage, Sangeeta; Nawaj, S.; Salek, C.; Lahiri, S.K.; Marathe, P.P.; Mukhopadhyay, S.; Taly, Y.K.

    2015-01-01

    Control rod position indication system is an important system in a nuclear power plant to monitor and display control rod position in all regimes of reactor operation. A new approach to design a control rod position indication system for sensing absolute position of control rod in Light Water Power Reactor has been undertaken. The proposed system employs an inductive type, hybrid measurement strategy providing both analog position as well as digital zone indication with built-in temperature compensation. The new design approach meets single failure criterion through redundancy in design without sacrificing measurement resolution. It also provides diversity in measurement technique by indirect position sensing based on analysis of drive coil current signature. Prototype development and qualification at room temperature of the control rod position indication system (CRPIS) has been demonstrated. The article presents the design philosophy of control rod position indication system, the new measurement strategy for sensing absolute position of control rod, position estimation algorithm for both direct and indirect sensing and a brief account associated processing electronics. (author)

  18. Influence of antibacterial therapy on bone scan indices at foot inflammation in diabetes mellitus accompanied by diabetic foot syndrome

    International Nuclear Information System (INIS)

    Slavnov, V.M.; Bolgars'ka, S.V.; Taran, E.V.; Markov, V.V.

    2004-01-01

    The influence of antibacterial therapy on bone scan indices at foot inflammation in patients with diabetes mellitus (DM) accompanied by diabetic foot syndrome was studied. Bone scan was performed using scintillation tomographic gamma-camera hours after intravenous injection of 99m Tc-methylene diphosphonate

  19. Validation of a new noniterative method for accurate position determination of a scanning laser vibrometer

    Science.gov (United States)

    Pauwels, Steven; Boucart, Nick; Dierckx, Benoit; Van Vlierberghe, Pieter

    2000-05-01

    The use of a scanning laser Doppler vibrometer for vibration testing is becoming a popular instrument. The scanning laser Doppler vibrometer is a non-contacting transducer that can measure many points at a high spatial resolution in a short time. Manually aiming the laser beam at the points that need to be measured is very time consuming. In order to use it effectively, the position of the laser Doppler vibrometer needs to be determined relative to the structure. If the position of the laser Doppler vibrometer is known, any visible point on the structure can be hit and measured automatically. A new algorithm for this position determination is developed, based on a geometry model of the structure. After manually aiming the laser beam at 4 or more known points, the laser position and orientation relative to the structure is determined. Using this calculated position and orientation a list with the mirror angles for every measurement point is generated, which is used during the measurement. The algorithm is validated using 3 practical cases. In the first case a plate is used of which the points are measured very accurately, so the geometry model is assumed to be perfect. The second case is a brake disc. Here the geometry points are measured with a ruler, thus not so accurate. The final validation is done on a body in white of a car. A reduced finite element model is used as geometry model. This calibration shows that the new algorithm is very effective and practically usable.

  20. Efficacy of brain scanning in epilepsy of late onset

    International Nuclear Information System (INIS)

    Jain, A.N.; Ramanathan, P.; Ganatra, R.D.

    1978-01-01

    Brain scans of 513 patients with epilepsy of late onset were analysed with reference to the patient's age and sex and to the nature of convulsion. Only 17 of them showed an abnormal concentration of radionuclide indicating a space-occupying lesion in the brain. The findings of those patients who had positive brain scans were correlated with EEG findings. It was found that the incidence of epilepsy of late onset is almost 3 times higher in males than in females and that the age cannot be considered as a criterion for screening the patients for brain scan investigation as far as epilepsy of late onset is concerned. In the authors' opinion, the incidence of 3.3% is not too low. A positive brain scan finding calls for further investigation and helps in deciding the management and further line of treatment of the patients. Moreover, a normal scan rules out the presence of a space-occupying lesion and helps as a screening procedure. (orig.) 891 MG [de

  1. Economic evaluation of reprocessing. Indicative Netherlands position

    International Nuclear Information System (INIS)

    1979-05-01

    The paper, which also appears as an Appendix to the final Working Group 4 report, forms part of the overall economic evaluation of reprocessing. The indicative national position and illustrative ''phase diagram'' for the Netherlands is presented. Two alternative scenarios have been assumed for the variation of uranium price in the future; a 2% per annum price rise and a 5% per annum price rise

  2. Angiotensin-I-converting enzyme and gallium scan in noninvasive evaluation of sarcoidosis

    Energy Technology Data Exchange (ETDEWEB)

    Nosal, A. (Harbor General Hospital, Torrance, CA); Schleissner, L.A.; Mishkin, F.S.; Lieberman, J.

    1979-03-01

    Angiotensin-converting enzyme assays and gallium-scan results were obtained from 27 patients with biopsy-proven, clinically active sarcoidosis. Twenty-three of these patients had elevated converting enzyme levels, and 22 had positive gallium-scan results. Three of four patients with normal or borderline-elevated levels of angiotensin-converting enzyme also had positive gallium-scan results. Of 156 nonsarcoid patients (pulmonary and other diseases), 27 were found to have elevated serum converting enzyme levels, and 25 of these had negative gallium-scan results. These results indicate that the combination of an assay of angiotensin-converting enzyme and gallium scan increases diagnostic specificity from 83% to 99% without sacrificing sensitivity. It was concluded that the concurrent use of angiotensin-converting enzyme assay and gallium scan is of value in the diagnosis of sarcoidosis.

  3. Angiotensin-I-converting enzyme and gallium scan in noninvasive evaluation of sarcoidosis

    International Nuclear Information System (INIS)

    Nosal, A.; Schleissner, L.A.; Mishkin, F.S.; Lieberman, J.

    1979-01-01

    Angiotensin-converting enzyme assays and gallium-scan results were obtained from 27 patients with biopsy-proven, clinically active sarcoidosis. Twenty-three of these patients had elevated converting enzyme levels, and 22 had positive gallium-scan results. Three of four patients with normal or borderline-elevated levels of angiotensin-converting enzyme also had positive gallium-scan results. Of 156 nonsarcoid patients (pulmonary and other diseases), 27 were found to have elevated serum converting enzyme levels, and 25 of these had negative gallium-scan results. These results indicate that the combination of an assay of angiotensin-converting enzyme and gallium scan increases diagnostic specificity from 83% to 99% without sacrificing sensitivity. It was concluded that the concurrent use of angiotensin-converting enzyme assay and gallium scan is of value in the diagnosis of sarcoidosis

  4. The uterine blush. A potential false-positive in Meckel's scan interpretation

    International Nuclear Information System (INIS)

    Fink-Bennett, D.

    1982-01-01

    To determine the presence, prevalence, and clinical importance of /sup 99m/Tc pertechnetate uterine uptake, this retrospective analysis of 71 Meckel's scans was undertaken. Specifically, each study was evaluated for the presence of a focal accumulation of radiotracer cephalad to the bladder. Patients received an intravenous dose of 150 microCi/kg of /sup 99m/Tc pertechnetate. Each study consisted of 15 one minute anterior serial gamma camera images, and a 15, 30, and 60 minute anterior, right lateral and posterior scintiscan. Menstrual histories were obtained from all patients except two. No males (33/33), nor premenstrual (13/13), menopausal (4/4) or posthysterectomy (2/2) patients revealed a uterine blush. Eleven of 15 patients (73%) with regular menses demonstrated a uterine blush. They were in the menstrual or secretory phases of their cycle. Four demonstrated no uterine uptake, had regular periods, but were in the proliferative phase of their cycle. Two with irregular periods, and one with no recorded menstrual history, manifested the blush. Radiotracer should be expected in the uterus during the menstrual and secretory phases of the menstrual cycle. It is a manifestation of a normal physiologic phenomenon, and must be recognized to prevent false-positive Meckel's scan interpretations

  5. Self-motivated visual scanning predicts flexible navigation in a virtual environment

    Directory of Open Access Journals (Sweden)

    Elisabeth Jeannette Ploran

    2014-01-01

    Full Text Available The ability to navigate flexibly (e.g., reorienting oneself based on distal landmarks to reach a learned target from a new position may rely on visual scanning during both initial experiences with the environment and subsequent test trials. Reliance on visual scanning during navigation harkens back to the concept of vicarious trial and error, a description of the side-to-side head movements made by rats as they explore previously traversed sections of a maze in an attempt to find a reward. In the current study, we examined if visual scanning predicted the extent to which participants would navigate to a learned location in a virtual environment defined by its position relative to distal landmarks. Our results demonstrated a significant positive relationship between the amount of visual scanning and participant accuracy in identifying the trained target location from a new starting position as long as the landmarks within the environment remain consistent with the period of original learning. Our findings indicate that active visual scanning of the environment is a deliberative attentional strategy that supports the formation of spatial representations for flexible navigation.

  6. Scanning of bone metastases

    International Nuclear Information System (INIS)

    Robillard, J.

    1977-01-01

    The Centers against cancer of Caen, Angers, Montpellier, Strasbourg and 'the Curie Foundation' have confronted their experience in detection of bone metastases by total body scanning. From the investigation by this procedure, of 1,467 patients with cancer, it results: the confrontation between radio and scanning shows a rate of false positive and false negative identical to the literature ones; the countage scanning allows to reduce the number of false positive; scanning allows to direct bone biopsy and to improve efficiency of histological examination [fr

  7. Position indicating systems and reed contact unit assemblies for such systems

    International Nuclear Information System (INIS)

    Foxworthy, M.K.

    1980-01-01

    Specifications are given for a position indicating system for determining the position of a movable member inside a sealed container such as the position of a control rod in a nuclear reactor. The system comprises a magnetic flux producing member mounted to the movable member so as to move with it, a series of magnetic reed contact units mounted along the outside of the sealed container to be individually actuated by the flux producer as the movable member moves within the sealed container to indicate the position of this member. Each of the reed contact units is connected to a source of alternating electric current to produce a magnetic flux field to minimize the flux differential between the actuated and unactuated reed contact positions. A second aspect of the invention provides for a low operating flux differential reed contact unit assembly for a position indicating system such that it is actuated by the magnetic member at one magnetic flux level and deactivated at a second level. There is a source of alternating current connected to a coil surrounding the reed contact unit so as to produce an alternating magnetic flux with amplitude less than the difference between the two levels. Variations are given, also diagrams and benefits. (U.K.)

  8. CT scanning in pediatric head trauma: correlation of clinical features with CT scan diagnosis

    International Nuclear Information System (INIS)

    Arkoncel, Mary Ann P.; Posadas, Ma. Belen A.

    1997-01-01

    A retrospective review was conducted on 205 cases of pediatric head trauma for which cranial computed tomography scans were done at the Makati Medical Center, to determine which clinical features might positively predict an abnormality on CT scan. The clinical findings of loss of consciousness, GCS < 12, vomiting headache, seizures, and focal abnormalities on Neurologic Examination were significantly associated with abnormal findings on CT scan. However, a significant discrepancy does exist as to how accurately clinical findings do in fact predict normal and abnormal CT scan findings. Such a discrepancy allows us to conclude that a more liberal use of CT Scanning in cases of pediatric head trauma must be stressed to insure proper diagnosis. This study shows that when a patient presents with the aforementioned positive signs and symptoms, or with a focal neurologic deficit, or in combination, a 60-100 % positive prediction of abnormal CT Scan can be made. However, prediction of normal CT Scan is only 0-40%. (Author)

  9. Economic evaluation of reprocessing. Indicative UK position

    International Nuclear Information System (INIS)

    1979-05-01

    This paper, which also appears as an Appendix to the final Working Group 4 report, forms part of the overall economic assessment of reprocessing. The indicative national position and illustrative ''phase diagram'' for the United Kingdom is presented. Under conditions pertaining in the United Kingdom the diagram suggests that: if uranium prices rise rapidly the fast reactor would become economic in the decade 1990-2000, if uranium prices rise more slowly, the fast reactor would become economic in the decade 2000-2010

  10. MutScan: fast detection and visualization of target mutations by scanning FASTQ data.

    Science.gov (United States)

    Chen, Shifu; Huang, Tanxiao; Wen, Tiexiang; Li, Hong; Xu, Mingyan; Gu, Jia

    2018-01-22

    Some types of clinical genetic tests, such as cancer testing using circulating tumor DNA (ctDNA), require sensitive detection of known target mutations. However, conventional next-generation sequencing (NGS) data analysis pipelines typically involve different steps of filtering, which may cause miss-detection of key mutations with low frequencies. Variant validation is also indicated for key mutations detected by bioinformatics pipelines. Typically, this process can be executed using alignment visualization tools such as IGV or GenomeBrowse. However, these tools are too heavy and therefore unsuitable for validating mutations in ultra-deep sequencing data. We developed MutScan to address problems of sensitive detection and efficient validation for target mutations. MutScan involves highly optimized string-searching algorithms, which can scan input FASTQ files to grab all reads that support target mutations. The collected supporting reads for each target mutation will be piled up and visualized using web technologies such as HTML and JavaScript. Algorithms such as rolling hash and bloom filter are applied to accelerate scanning and make MutScan applicable to detect or visualize target mutations in a very fast way. MutScan is a tool for the detection and visualization of target mutations by only scanning FASTQ raw data directly. Compared to conventional pipelines, this offers a very high performance, executing about 20 times faster, and offering maximal sensitivity since it can grab mutations with even one single supporting read. MutScan visualizes detected mutations by generating interactive pile-ups using web technologies. These can serve to validate target mutations, thus avoiding false positives. Furthermore, MutScan can visualize all mutation records in a VCF file to HTML pages for cloud-friendly VCF validation. MutScan is an open source tool available at GitHub: https://github.com/OpenGene/MutScan.

  11. Development of control rod position indicator using seismic-resistance reed switches for integral reactor

    International Nuclear Information System (INIS)

    Yu, Je Yong; Kim, Ji Ho; Huh, Hyung; Choi, Myoung Hwan; Sohn, Dong Seong

    2008-01-01

    The Reed Switch Position Transmitter (RSPT) is used as a position indicator for the control rod in commercial nuclear power plants made by ABB-CE. But this position indicator has some problems when directly adopting it to the integral reactor. The Control Element Drive Mechanism (CEDM) for the integral reactor is designed to raise and lower the control rod in steps of 2mm in order to satisfy the design features of the integral reactor which are the soluble boron free operation and the use of a nuclear heating for the reactor start-up. Therefore the resolution of the position indicator for the integral reactor should be achieved to sense the position of the control rod more precisely than that of the RSPT of the ABB-CE. This paper adopts seismic resistance reed switches to the position indicator in order to reduce the damages or impacts during the handling of the position indicator and earthquake

  12. [Indications and instructions to patients for a positron emission tomography-PET scan. The importance of the hybridic PET/CT-computerised tomography scan and which specialty should be responsible for its function].

    Science.gov (United States)

    Grammaticos, Philip; Datseris, Ioannis; Gerali, Sofia; Papantoniou, Vassilios; Valsamaki, Pipitsa; Boundas, Dimitrios

    2007-01-01

    Indications and instructions to patients for performing a positron emission tomography - PET scan are mentioned. Although PET camera was developed in 1970 its clinical indications were established in about 1998. The hybridic PET/CT- computerized tomography scanner appeared in 2001 and its clinical indications are still under discussion. These discussions refer to both the use of PET/CT as an acquisition correction and anatomic localization device for PET images (AC/A) and to its use as a diagnostic CT scan (dCT). Most of the patients submitted for a PET scan have already done a dCT scan. This was the case in 286 out of the first 300 patients referred to "Evangelismos" hospital in Athens for a PET scan. These two scans can be matched electronically. Extra cost, space, personnel and radiation absorption dose especially in children, are additional factors to be considered in using the PET/CT scanner. The specialty of Nuclear Medicine is now based on the PET camera, its best part and main equipment for molecular imaging. It is very much easier and faster for a Nuclear Medicine physician who routinely reports tomographic PET and SPET images, to be familiar with the CT images than for a Radiologist to get to "know how" about the PET camera and the whole Nuclear Medicine Department. Nuclear Medicine is about open radiation sources, molecular imaging, specific radio-pharmacology, radiobiology, radiation protection etc, while on the other hand in some countries, Nuclear Physicians have already spent, as part of their official training, six months in a Radiology Department whose function is considered to be at least 25% about the CT scanner. We come to the conclusion that the PET/CT scanner should be under the responsibility of the Nuclear Medicine Department and the Radiologist should act as an advisor.

  13. Influence of PET/CT-introduction on PET scanning frequency and indications. Results of a multicenter study

    International Nuclear Information System (INIS)

    Stergar, H.; Bockisch, A.; Eschmann, S.M.; Krause, B.J.; Roedel, R.; Tiling, R.; Weckesser, M.

    2007-01-01

    Aim: to evaluate the influence of the introduction of combined PET/CT scanners into clinical routine. This investigation addresses the quantitative changes between PET/CT and stand alone PET. Methods: the study included all examinations performed on stand alone PET- or PET/CT-scanners within 12 month prior to and after implementation of PET/CT. The final data analysis included five university hospitals and a total number of 15 497 exams. We distinguished exams on stand alone tomographs prior to and after installation of the combined device as well as PET/CT scans particularly with regard to disease entities. Various further parameters were investigated. Results: the overall number of PET scans (PET and PET/CT) rose by 146% while the number of scans performed on stand alone scanners declined by 22%. Only one site registered an increase in stand alone PET. The number of exams for staging in oncology increased by 196% while that of cardiac scans decreased by 35% and the number of scans in neurology rose by 47%. The use of scans for radiotherapy planning increased to 7% of all PET/CT studies. The increase of procedures for so-called classic PET oncology indications was moderate compared to the more common tumors. An even greater increase was observed in some rare entities. Conclusions: the introduction of PET/CT led to more than a doubling of overall PET procedures with a main focus on oncology. Some of the observed changes in scanning frequency may be caused by a rising availability of new radiotracers and advancements of competing imaging methods. Nevertheless the evident increase in the use of PET/CT for the most common tumour types demonstrates its expanding role in cancer staging. The combination of molecular and morphologic imaging has not only found its place but is still gaining greater importance with new developments in technology and radiochemistry. (orig.)

  14. A genome scan for positive selection in thoroughbred horses.

    Science.gov (United States)

    Gu, Jingjing; Orr, Nick; Park, Stephen D; Katz, Lisa M; Sulimova, Galina; MacHugh, David E; Hill, Emmeline W

    2009-06-02

    Thoroughbred horses have been selected for exceptional racing performance resulting in system-wide structural and functional adaptations contributing to elite athletic phenotypes. Because selection has been recent and intense in a closed population that stems from a small number of founder animals Thoroughbreds represent a unique population within which to identify genomic contributions to exercise-related traits. Employing a population genetics-based hitchhiking mapping approach we performed a genome scan using 394 autosomal and X chromosome microsatellite loci and identified positively selected loci in the extreme tail-ends of the empirical distributions for (1) deviations from expected heterozygosity (Ewens-Watterson test) in Thoroughbred (n = 112) and (2) global differentiation among four geographically diverse horse populations (F(ST)). We found positively selected genomic regions in Thoroughbred enriched for phosphoinositide-mediated signalling (3.2-fold enrichment; PThoroughbred athletic phenotype. We report for the first time candidate athletic-performance genes within regions targeted by selection in Thoroughbred horses that are principally responsible for fatty acid oxidation, increased insulin sensitivity and muscle strength: ACSS1 (acyl-CoA synthetase short-chain family member 1), ACTA1 (actin, alpha 1, skeletal muscle), ACTN2 (actinin, alpha 2), ADHFE1 (alcohol dehydrogenase, iron containing, 1), MTFR1 (mitochondrial fission regulator 1), PDK4 (pyruvate dehydrogenase kinase, isozyme 4) and TNC (tenascin C). Understanding the genetic basis for exercise adaptation will be crucial for the identification of genes within the complex molecular networks underlying obesity and its consequential pathologies, such as type 2 diabetes. Therefore, we propose Thoroughbred as a novel in vivo large animal model for understanding molecular protection against metabolic disease.

  15. The utility of repeat sestamibi scans in patients with primary hyperparathyroidism after an initial negative scan.

    Science.gov (United States)

    Krishnamurthy, Vikram D; Sound, Sara; Okoh, Alexis K; Yazici, Pinar; Yigitbas, Hakan; Neumann, Donald; Doshi, Krupa; Berber, Eren

    2017-06-01

    We analyzed the utility of repeated sestambi scans in patients with primary hyperparathyroidism and its effects on operative referral. We carried out a retrospective review of patients with primary hyperparathyroidism who underwent repeated sestambi scans exclusively within our health system between 1996-2015. Patient demographic, presentation, laboratory, imaging, operative, and pathologic data were reviewed. Univariate analysis with JMP Pro v12 was used to identify factors associated with conversion from an initial negative to a subsequent positive scan. After exclusion criteria (including reoperations), we identified 49 patients in whom 59% (n = 29) of subsequent scans remained negative and 41% (n = 20) converted to positive. Factors associated with an initial negative to a subsequent positive scan included classic presentation and second scans with iodine subtraction (P = .04). Nonsurgeons were less likely to order an iodine-subtraction scan (P < .05). Fewer patients with negative imaging were referred to surgery (33% vs 100%, P = .005), and median time to operation after the first negative scan was 25 months (range 1.4-119). Surgeon-performed ultrasonography had greater sensitivity and positive predictive value than repeated sestamibi scans. Negative sestambi scans decreased and delayed operative referral. Consequently, we identified several process improvement initiatives, including education regarding superior institutional imaging. Combining all findings, we created an algorithm for evaluating patients with primary hyperparathyroidism after initially negative sestamibi scans, which incorporates surgeon-performed ultrasonography. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Gallium scan in recurrent Hodgkin's disease in children

    International Nuclear Information System (INIS)

    Yeh, S.D.; Benua, R.S.; Tan, C.T.

    1979-01-01

    In 18 of 88 children with biopsy proven and previously untreated Hodgkin's disease, recurrence developed during a period from four to 53 months after therapy (median period, 22 months). In 16 patients in whom gallium scans were performed, 21 positive gallium scans were obtained during 26 episodes of recurrence. Abnormalities were noted in half of them during a period from one to 10 months prior to physical, laboratory, radiographic or histologic confirmation of recurrence (median period about 5 months). We have concluded that the gallium scan is very useful in initial workup and is sensitive in detecting early recurrence in children with Hodgkin's disease. Such scans are indicated when there is clinical suspicion of recurrence, when other modalities are unavailable or when the results of other studies are equivocal

  17. Multiple myeloma: radiology or bone scanning

    International Nuclear Information System (INIS)

    Leonard, R.C.F.; Owen, J.P.; Proctor, S.J.; Hamilton, P.J.

    1981-01-01

    A comparative study of radionuclide bone scanning and skeletal radiology in patients with multiple myeloma revealed four principal findings: (i) There were no cases of negative bone scans with positive skeletal radiographs. (ii) Lytic bone lesions were seriously underestimated by bone scans. (iii) Bone scans tended to pick up lesions in ribs missed on the skeletal surveys. (iv) Patients with bone pain were more likely to have positive bone scans and skeletal radiographs than asymptomatic patients. (author)

  18. False-positive liver scans due to portal hypertension: correlation with percutaneous transhepatic portograms in 33 patients

    International Nuclear Information System (INIS)

    Takayasu, K.; Moriyama, N.; Suzuki, M.; Yamada, T.; Fukutake, T.; Shima, Y.; Kobayashi, C.; Musha, H.; Okuda, K.

    1983-01-01

    Tc-99m-phytate scanning of the liver and percutaneous transhepatic catheterization of the portal vein were performed in 33 patients--26 with cirrhosis, 3 with chronic active hepatitis, 2 with idiopathic portal hypertension, and 2 with unresolved acute hepatitis. A discrete defect in the porta hepatis area was seen in 6 of 28 patients who had portal vein pressure above 200 mm H2O. In 5 of the 6 patients with a false-positive scan, the umbilical portion of the left portal vein branch was dilated (larger than 25 x 20 mm) on the portogram, with or without a patent paraumbilical vein. The anatomical basis of this phenomenon is discussed, and it is suggested that this area be given special attention

  19. Performance estimation of control rod position indicator due to aging of magnet

    International Nuclear Information System (INIS)

    Yu, Je Yong; Kim, Ji Ho; Huh, Hyung; Choi, Myoung Hwan; Sohn, Dong Seong

    2009-01-01

    The Control Element Drive Mechanism (CEDM) for the integral reactor is designed to raise and lower the control rod in steps of 2mm in order to satisfy the design features of the integral reactor which are the soluble boron free operation and the use of a nuclear heating for the reactor start-up. The actual position of the control rod could be achieved to sense the magnet connected to the control rod by the position indicator around the upper pressure housing of CEDM. It is sufficient that the actual position information of control rod at 20mm interval from the position indicator is used for the core safety analysis. As the magnet moves upward along the position indicator assembly from the bottom to the top in the upper pressure housing, the output voltage increases linearly step-wise at 0.2VDC increments. Between every step there are transient areas which occur by a contact closing of three reed switches which is the 2-3-2 contact closing sequence. In this paper the output voltage signal corresponding to the position of control rod was estimated on the 2-1-2 contact closing sequence due to the aging of the magnet.

  20. Positive findings on bone scan in multiple myeloma

    International Nuclear Information System (INIS)

    Lin Lin

    2004-01-01

    We report a case of multiple myeloma in which the CT only shows osteolytic lesions and MRI only shows compressive fractrue, but the scan shows some interesting imaging that make us to think of multiple myeloma. (authors)

  1. Bone scanning in the evaluation of lung cancer

    International Nuclear Information System (INIS)

    Jung, Kun Sik; Zeon, Seok Kil; Lee, Hee Jung; Song, Hong Suk

    1994-01-01

    We studied the diagnostic significance of bone scan in evaluation of bone metastasis by lung cancer, prevalence rate, and the causes of false positive bone scan and soft tissue accumulation of bone seeking agent. This subject include 73 lung cancer patients with bone scan, We analyzed the frequency of the metastasis, its distribution and configuration, and any relationship between bone pain and corresponding region on bone scan. The positive findings of bone scans were compared with simple X-ray film, CT, MRI and other diagnostic modalities. The false positive bone scan and the soft tissue accumulation of bone seeking agent were analyzed. The positive findings on bone scan were noted in 26 cases(36%) and they were coexistent with bone pain in 30%. The correspondence between bone scan and bone X-ray was 38%. False positive bone scans were seen in 12 cases(16%), which include fracture due to thoracotomy and trauma, degenerative bone disease, and bifid rib. Accumulation of bone seeking agent in soft tissue were seen in 13 cases(18%), which included primary tumor, enlarged cervical lymph node, pleural effusion, ascites and pleural thickening. Bone scans should be carefully interpreted in detecting bone metastasis in primary malignancy, because of the 16% false positivity and 18% soft tissue accumulation rate. It is very important to note that the correlation between bone pain and positive findings of bone scans was only 38%

  2. Bone scanning in the evaluation of lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kun Sik; Zeon, Seok Kil; Lee, Hee Jung; Song, Hong Suk [School of Medicine, Keimyung University, Daegu (Korea, Republic of)

    1994-05-15

    We studied the diagnostic significance of bone scan in evaluation of bone metastasis by lung cancer, prevalence rate, and the causes of false positive bone scan and soft tissue accumulation of bone seeking agent. This subject include 73 lung cancer patients with bone scan, We analyzed the frequency of the metastasis, its distribution and configuration, and any relationship between bone pain and corresponding region on bone scan. The positive findings of bone scans were compared with simple X-ray film, CT, MRI and other diagnostic modalities. The false positive bone scan and the soft tissue accumulation of bone seeking agent were analyzed. The positive findings on bone scan were noted in 26 cases(36%) and they were coexistent with bone pain in 30%. The correspondence between bone scan and bone X-ray was 38%. False positive bone scans were seen in 12 cases(16%), which include fracture due to thoracotomy and trauma, degenerative bone disease, and bifid rib. Accumulation of bone seeking agent in soft tissue were seen in 13 cases(18%), which included primary tumor, enlarged cervical lymph node, pleural effusion, ascites and pleural thickening. Bone scans should be carefully interpreted in detecting bone metastasis in primary malignancy, because of the 16% false positivity and 18% soft tissue accumulation rate. It is very important to note that the correlation between bone pain and positive findings of bone scans was only 38%.

  3. An interchangeable scanning Hall probe/scanning SQUID microscope

    International Nuclear Information System (INIS)

    Tang, Chiu-Chun; Lin, Hui-Ting; Wu, Sing-Lin; Chen, Tse-Jun; Wang, M. J.; Ling, D. C.; Chi, C. C.; Chen, Jeng-Chung

    2014-01-01

    We have constructed a scanning probe microscope for magnetic imaging, which can function as a scanning Hall probe microscope (SHPM) and as a scanning SQUID microscope (SSM). The scanning scheme, applicable to SHPM and SSM, consists of a mechanical positioning (sub) micron-XY stage and a flexible direct contact to the sample without a feedback control system for the Z-axis. With the interchangeable capability of operating two distinct scanning modes, our microscope can incorporate the advantageous functionalities of the SHPM and SSM with large scan range up to millimeter, high spatial resolution (⩽4 μm), and high field sensitivity in a wide range of temperature (4.2 K-300 K) and magnetic field (10 −7 T-1 T). To demonstrate the capabilities of the system, we present magnetic images scanned with SHPM and SSM, including a RbFeB magnet and a nickel grid pattern at room temperature, surface magnetic domain structures of a La 2/3 Ca 1/3 MnO 3 thin film at 77 K, and superconducting vortices in a striped niobium film at 4.2 K

  4. A hand-held 3D laser scanning with global positioning system of subvoxel precision

    International Nuclear Information System (INIS)

    Arias, Nestor; Meneses, Nestor; Meneses, Jaime; Gharbi, Tijani

    2011-01-01

    In this paper we propose a hand-held 3D laser scanner composed of an optical head device to extract 3D local surface information and a stereo vision system with subvoxel precision to measure the position and orientation of the 3D optical head. The optical head is manually scanned over the surface object by the operator. The orientation and position of the 3D optical head is determined by a phase-sensitive method using a 2D regular intensity pattern. This phase reference pattern is rigidly fixed to the optical head and allows their 3D location with subvoxel precision in the observation field of the stereo vision system. The 3D resolution achieved by the stereo vision system is about 33 microns at 1.8 m with an observation field of 60cm x 60cm.

  5. Economic evaluation of reprocessing - Indicative Canadian position

    International Nuclear Information System (INIS)

    1979-05-01

    This paper, which also appears as an Appendix to the final Working Group 4 report, forms part of the overall economic evaluation of reprocessing. The indicative national position and illustrative ''phase diagram'' for Canada is presented. Three fuel cycles are considered. (1) CANDU operating on the natural uranium, once-through fuel cycle. (2) CANDU operating with low enrichment (1.2%) once-through fuel cycle. (3) CANDU operating with recycle of plutonium and depleted uranium which has been extracted from spent CANDU natural uranium fuel. The diagrams show that reprocessing and recycle of fuel can be used to reduce further the sensitivity of CANDU fuelling costs to increasing uranium ore price

  6. Economic evaluation of reprocessing - Indicative German position

    International Nuclear Information System (INIS)

    1979-05-01

    This paper, which also appears as an Appendix to the final Working Group 4 report, forms part of the overall economic assessment of reprocessing. The indicative national position and illustrative ''phase diagram'' for the Federal Republic of Germany is presented. Advantages to be gained from the recycling of plutonium in thermal reactors are identified and it is concluded that many of these are not explicitly taken into account in the ''phase diagram''. Under the conditions pertaining in the Federal Republic of Germany thermal recycle will be economic under present day uranium prices. On the other hand the fast breeder reactor might become commercially economic around the year 2000

  7. Role of technetium-99m planar bone scanning in the evaluation of low back pain

    International Nuclear Information System (INIS)

    Valdez, D.C.; Johnson, R.G.

    1994-01-01

    The records of 1018 patients with low back pain in a tertiary spine referral practice were reviewed. One hundred thirty-nine out of 1018 (13.6%) underwent technetium-99m planar bone scannings as part of their investigation. Seventy-three out of 139 scans (52%) showed increased uptake in some area, but only 27 out of 139 (19.4%) showed increased uptake specifically in the low back. Scans consistently yielded no findings with reference to the back when the prescan diagnosis was spinal stenosis, lumbar pain syndrome, herniated nucleus pulposus, or postlaminectomy syndrome. Some scans gave positive findings in patients with a diagnosis of degenerative disc disease, pseudoarthrosis, spondylolisthesis, fracture, infection, metabolic disorder, or tumor. Positive scans were generally obtained early after presentation (within 3 months) and negative scans obtained later (after 6 months), suggesting that clinical suspicion is still the main indication for early scanning. Planar bone scanning was helpful in both diagnosis and therapeutic decision-making in many conditions. (orig.)

  8. Early appearance of SARS on chest CT scan

    International Nuclear Information System (INIS)

    Cheng Xiaoguang; Feng Suchen; Xia Guoguang; Zhao Tao; Gu Xiang; Qu Hui

    2003-01-01

    Objective: To evaluate the early appearance of SARS on chest CT scan and its role in the early diagnosis. Methods: Forty cases of SARS in keeping with the criteria of the Ministry of Health had chest CT scans within 7 days of onset of symptoms, and CR chest X-ray films were available as well. These chest X-rays and CT images were retrospectively reviewed to determine if there were any abnormalities on the images. The lesions on the chest CT images were then further analyzed in terms of the number, location, size, and density. Results: Positive abnormalities on chest CT scans were revealed in all 40 SARS cases. Positive findings on CR chest films were showed in only 25 cases, equivocal in 6, and normal in 9 cases. The main abnormalities seen on CT and X-rays were pulmonary infiltrations varied markedly in severity. 70 % cases had 1 or 2 lesions on chest CT scan, 30 % cases had 3 or more lesions. The lesions seen on chest CT scan tended to be ground-glass opacification, sometimes with consolidation which was very faint and inhomogeneous, easily missed on chest X-rays. Typically the lesions were located in the periphery of the lung, or both central and peripheral lung, but very rare in a pure central location. They were commonly in the shape of patch or ball. Conclusions: Chest CT scan is much more sensitive in detecting the lesions of the lung in SARS. The early appearance of SARS on chest CT scan is characteristic but non-specific, indicating that chest CT scan plays a very important role in the early diagnosis and differential diagnosis of SARS

  9. Position display device

    International Nuclear Information System (INIS)

    Nishizawa, Yukio.

    1974-01-01

    Object: To provide a device capable of easily and quickly reading mutual mounting relations of control bodies such as control rods mounted on a nuclear reactor and positions to which the control bodies are driven. Structure: A scanning circuit is provided to scan positions of controllably mounted control bodies such as control rods. Values detected by scanning the positions are converted into character signals according to the values and converted into preranked color signals. The character signals and color signals are stored in a memory circuit by synchronous signals in synchronism with the scanning in the scanning circuit. Outputs of the memory circuit are displayed by a display unit such as a color Braun tube in accordance with the synchronous signals to provide color representations according to positions to which control bodies are driven in the same positional relation as the mounting of the control bodies. (Kamimura, M.)

  10. Low back pain: an assessment using positional MRI and MDT.

    Science.gov (United States)

    Hedberg, Karen; Alexander, Lyndsay A; Cooper, Kay; Hancock, Elizabeth; Ross, Jenny; Smith, Francis W

    2013-04-01

    Current guidelines advise against the use of routine imaging for low back pain. Positional MRI can provide enhanced assessment of the lumbar spine in functionally loaded positions which are often relevant to the presenting clinical symptoms. The purpose of this case report is to highlight the use of positional MRI in the assessment and classification of a subject with low back pain. A low back pain subject underwent a Mechanical Diagnosis and Therapy (MDT) assessment and positional MRI scan of the lumbar spine. The MDT assessment classified the subject as "other" since the subjective history indicated a possible posterior derangement whilst the objective assessment indicated a possible anterior derangement. Positional MRI scanning in flexed, upright and extended sitting postures confirmed the MDT assessment findings to reveal a dynamic spinal stenosis which reduced in flexion and increased in extension. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. The uterine blush. A potential false-positive in Meckel's scan interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Fink-Bennett, D.

    1982-10-01

    To determine the presence, prevalence, and clinical importance of /sup 99m/Tc pertechnetate uterine uptake, this retrospective analysis of 71 Meckel's scans was undertaken. Specifically, each study was evaluated for the presence of a focal accumulation of radiotracer cephalad to the bladder. Patients received an intravenous dose of 150 microCi/kg of /sup 99m/Tc pertechnetate. Each study consisted of 15 one minute anterior serial gamma camera images, and a 15, 30, and 60 minute anterior, right lateral and posterior scintiscan. Menstrual histories were obtained from all patients except two. No males (33/33), nor premenstrual (13/13), menopausal (4/4) or posthysterectomy (2/2) patients revealed a uterine blush. Eleven of 15 patients (73%) with regular menses demonstrated a uterine blush. They were in the menstrual or secretory phases of their cycle. Four demonstrated no uterine uptake, had regular periods, but were in the proliferative phase of their cycle. Two with irregular periods, and one with no recorded menstrual history, manifested the blush. Radiotracer should be expected in the uterus during the menstrual and secretory phases of the menstrual cycle. It is a manifestation of a normal physiologic phenomenon, and must be recognized to prevent false-positive Meckel's scan interpretations.

  12. CLINICOPATHOLOGICAL FACTORS ASSOCIATED WITH POSITIVE PREOPERATIVE AXILLARY ULTRASOUND SCANNING IN BREAST CANCER PATIENTS

    Directory of Open Access Journals (Sweden)

    Lona Jalini

    2016-01-01

    Full Text Available Background: Axillary lymph node status is the most important breast cancer prognostic factor. Preoperative axillary ultrasound examination (PAUS is used to triage patients for sentinel lymph node biopsy (SLNB or axillary lymph node dissection (ALND. We assessed the detection rate of lymph node metastases by PAUS in a screening unit and evaluated associations between clinicopathological factors and PAUS positivity. Patients and Methods: This was a single-centre retrospective analysis of data extracted from a hospital breast cancer database and clinical records. Clinical, radiological, and pathological and prognostic indices were compared between PAUS-positive and PAUS-negative patients subsequently found to have lymph node metastases on histopathological analysis. Results: Two hundred and two patients were eligible for analysis. 50.5% of lymph node-positive patients were correctly identified as PAUS positive. Patients with PAUS-positive lymph nodes had less favorable disease characteristics, namely clinically palpable lymph nodes, higher Nottingham prognostic (NPI index, high lymph node burden according to the European Society of Medical Oncology (ESMO group classification, and larger, grade 3 tumors with lymphovascular invasion and extranodal spread. Moreover, PAUS-positive patients had more macrometastases and lymph node involvement than PAUS-negative patients. Conclusion: PAUS-positive patients and PAUS-negative (SLNB-positive patients have different clinicopathological characteristics. The presence of LVI, extranodal spread, grade 3 histology, or large tumors with poor prognostic indices in PAUS-negative patients should be regarded with caution and perhaps prompt second-look ultrasound examination.

  13. An interchangeable scanning Hall probe/scanning SQUID microscope

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Chiu-Chun; Lin, Hui-Ting; Wu, Sing-Lin [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Chen, Tse-Jun; Wang, M. J. [Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 10617, Taiwan (China); Ling, D. C. [Department of Physics, Tamkang University, Tamsui Dist., New Taipei City 25137, Taiwan (China); Chi, C. C.; Chen, Jeng-Chung [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu 30013, Taiwan (China)

    2014-08-15

    We have constructed a scanning probe microscope for magnetic imaging, which can function as a scanning Hall probe microscope (SHPM) and as a scanning SQUID microscope (SSM). The scanning scheme, applicable to SHPM and SSM, consists of a mechanical positioning (sub) micron-XY stage and a flexible direct contact to the sample without a feedback control system for the Z-axis. With the interchangeable capability of operating two distinct scanning modes, our microscope can incorporate the advantageous functionalities of the SHPM and SSM with large scan range up to millimeter, high spatial resolution (⩽4 μm), and high field sensitivity in a wide range of temperature (4.2 K-300 K) and magnetic field (10{sup −7} T-1 T). To demonstrate the capabilities of the system, we present magnetic images scanned with SHPM and SSM, including a RbFeB magnet and a nickel grid pattern at room temperature, surface magnetic domain structures of a La{sub 2/3}Ca{sub 1/3}MnO{sub 3} thin film at 77 K, and superconducting vortices in a striped niobium film at 4.2 K.

  14. The Utility and indication of FDG-PET scan in patients with cervical cancer: experience in patients with no evidence of recurrence with conventional radiologic examination and tumor markers

    International Nuclear Information System (INIS)

    Kim, Jong Hoon

    2000-12-01

    The purpose of this study was to investigate the clinical feasibility of FDG-PET(Positron Emission Tomography) scan in patients with clinically no evidence of disease after treatment of cervical cancer. One hundred and one patients with clinically NED(no evidence of disease) state after treatment of cervical cancer underwent PET scan. FDG-PET scan was obtained with a GE Advance Scanner, beginning at 50 minutes after injection of 370-555 MBq(10-15 mCi) of 18F FDG. Regional scan was also obtained with emission image. Uptake exceeding 3.0 SUV was determined as a positive finding. Recurrence was confirmed by CT, MRI, and needle biopsy if possible. Among 101 patients showing no evidence of disease, 17 patients(16.8%) showed abnormal PET scan findings. Clinically, 8 patients(7.9%) were confirmed to have recurrent lesion by CT, MRI or by needle biopsy. PET scan could detect recurrent lesions in the mediastinum or lung(10/17), pelvis(7/17), and supraclavicular lymph node(2/17). The sensitivity and specificity of PET scan in patients with cervical cancer showing no evidence of disease were 100% and 90.3%, respectively. The positive predictive value, negative predictive value and false positive rate were 47.1%, 100% and 52.9%. PET scan could detect 7.9% of early recurrence in patients with cervical cancer with NED status. FDG-PET scan may be a useful method in detecting metastases or recurrence of a cervical cancer showing no evidence of disease by routine conventional imaging studies

  15. Comparison of CPR1000 and AP1000 rod position indication systems

    International Nuclear Information System (INIS)

    Lei Qing

    2009-01-01

    This paper introduces the structure, the function, the digital detection principle of reactor control rod position and monitoring systems in CPR1000 and AP1000, comparing with the characteristics of the system design. The results show that the operation mode and function of AP1000 Rod position indication system are similar to that of CPR1000, but AP1000 rod position system provides higher reliability, and reduces the numbers of containment electrical penetrations and is with better characteristics than that of CPR1000, since it incorporated the redundancy design and data communication. (authors)

  16. A genome scan for positive selection in thoroughbred horses.

    Directory of Open Access Journals (Sweden)

    Jingjing Gu

    2009-06-01

    Full Text Available Thoroughbred horses have been selected for exceptional racing performance resulting in system-wide structural and functional adaptations contributing to elite athletic phenotypes. Because selection has been recent and intense in a closed population that stems from a small number of founder animals Thoroughbreds represent a unique population within which to identify genomic contributions to exercise-related traits. Employing a population genetics-based hitchhiking mapping approach we performed a genome scan using 394 autosomal and X chromosome microsatellite loci and identified positively selected loci in the extreme tail-ends of the empirical distributions for (1 deviations from expected heterozygosity (Ewens-Watterson test in Thoroughbred (n = 112 and (2 global differentiation among four geographically diverse horse populations (F(ST. We found positively selected genomic regions in Thoroughbred enriched for phosphoinositide-mediated signalling (3.2-fold enrichment; P<0.01, insulin receptor signalling (5.0-fold enrichment; P<0.01 and lipid transport (2.2-fold enrichment; P<0.05 genes. We found a significant overrepresentation of sarcoglycan complex (11.1-fold enrichment; P<0.05 and focal adhesion pathway (1.9-fold enrichment; P<0.01 genes highlighting the role for muscle strength and integrity in the Thoroughbred athletic phenotype. We report for the first time candidate athletic-performance genes within regions targeted by selection in Thoroughbred horses that are principally responsible for fatty acid oxidation, increased insulin sensitivity and muscle strength: ACSS1 (acyl-CoA synthetase short-chain family member 1, ACTA1 (actin, alpha 1, skeletal muscle, ACTN2 (actinin, alpha 2, ADHFE1 (alcohol dehydrogenase, iron containing, 1, MTFR1 (mitochondrial fission regulator 1, PDK4 (pyruvate dehydrogenase kinase, isozyme 4 and TNC (tenascin C. Understanding the genetic basis for exercise adaptation will be crucial for the identification of genes

  17. Positioning irrigation of contrast cystography for diagnosis of occult vesicoureteric reflux: association with technetium-99m dimercaptosuccinic acid scans.

    Science.gov (United States)

    Berger, Christoph; Becker, Tanja; Koen, Mark; Zeino, Mazen; Fitz, Friedrich; Beheshti, Mohsen; Wolf-Kohlmeier, Iris; Haim, Silke; Riccabona, Marcus

    2013-12-01

    Positioning irrigation of contrast (PIC) cystography identifies occult or PIC vesicoureteral reflux (PIC-VUR) in children with recurrent febrile urinary tract infections (UTI) but no vesicoureteric reflux (VUR) on standard voiding cystourethrogram (VCUG). We sought to identify the relationship between PIC-VUR and renal scarring in technetium-99m dimercaptosuccinic acid (DMSA) scans. We retrospectively analysed PIC cystograms and DMSA scans for 154 kidneys in 81 children (65 girls; 16 boys; median age, 4.7 years; range, 0.9-15.2). Renal scarring was graded on a scale of 0-3. DMSA scans were pathologic in 66 patients (81%). Children had experienced mean 3.8 febrile UTI (range 1-25). Forty-seven (58%) children had a history of reflux, including 15 (19%) with previous anti-reflux operations. Indications for PIC cystography were recurrence of febrile UTI after either bilateral negative VCUG (66 children) or unilateral VUR (15 children) with contralateral/bilateral scarring or reflux that had changed sides in subsequent VCUGs. PIC-VUR was bilateral in 63, unilateral in 12, and absent in 6 children. Statistically significant associations between PIC-VUR grade and severity of renal scarring were identified in inter-individual (n = 77, p = 0.017) and intra-individual (refluxing vs. nonrefluxing kidney; n = 12, p = 0.008) analyses. After excluding patients with history of VUR, statistical significance was maintained in inter-individual analysis (n = 49; p = 0.018). The data suggest an association between PIC-VUR and severity of renal scarring, and legitimise the use of PIC cystography in children with renal scarring due to recurrent febrile UTI but negative findings on VCUG. Copyright © 2012 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

  18. Compact very low temperature scanning tunneling microscope with mechanically driven horizontal linear positioning stage.

    Science.gov (United States)

    Suderow, H; Guillamon, I; Vieira, S

    2011-03-01

    We describe a scanning tunneling microscope for operation in a dilution refrigerator with a sample stage which can be moved macroscopically in a range up to a cm and with an accuracy down to the tens of nm. The position of the tip over the sample as set at room temperature does not change more than a few micrometers when cooling down. This feature is particularly interesting for work on micrometer sized samples. Nanostructures can be also localized and studied, provided they are repeated over micrometer sized areas. The same stage can be used to approach a hard single crystalline sample to a knife and cleave it, or break it, in situ. In situ positioning is demonstrated with measurements at 0.1 K in nanofabricated samples. Atomic resolution down to 0.1 K and in magnetic fields of 8 T is demonstrated in NbSe(2). No heat dissipation nor an increase in mechanical noise has been observed at 0.1 K when operating the slider.

  19. Selenomethionine Se 75 thymus scans in myasthenia gravis

    Energy Technology Data Exchange (ETDEWEB)

    Toole, J.F.; Cowan, R.; Maynard, D.; Witcofski, R.L.; Janeway, R.

    1975-01-01

    In 1966, Toole and Witcofski introduced selenomethionine Se 75 mediastinal scanning as a diagnostic test for thymomas. Since then we have performed such scans on patients with myasthenic syndrome. Because the technique is atraumatic, safe, and accurate, it can be performed on critically ill myasthenics. Two hundred and fifty microcuries of selenomethionine Se 75 is injected intravenously. Within 1 hour the mediastinum from the suprasternal notch to the ziphoid process is scanned, using a 2 x 3 inch scanner. Delayed scans have been made in a few instances but they have not increased the number of positive cases. Selenomethionine Se 75 is incorporated into tissues undergoing rapid protein synthesis such as thyroid, pancreas, liver, and lymphomas. Of the 34 mediastinal scans performed on myasthenics between 1966 and December 31, 1974, 4 were positive for thymoma. In addition, there was a positive scan with uptake in an area of atelectasis of the lung adjacent to the mediastinum. Of interest is the fact that 1 patient with carcinoma of the lung had a positive scan over the lesion. In 13 patients with chronic lymphatic leukemia the mediastinal scans were negative. In another patient with a mediastinal mass noted on chest x-ray, a variety of differential diagnostic possibilities were considered, such as pericardial cyst, dermoid, and aneurysm. A selenomethionine scan was strongly positive, suggesting a thymoma which subsequent surgery confirmed.

  20. Analysis of Carina Position as Surrogate Marker for Delivering Phase-Gated Radiotherapy

    International Nuclear Information System (INIS)

    Weide, Lineke van der; Soernsen de Koste, John R. van; Lagerwaard, Frank J.; Vincent, Andrew; Triest, Baukelien van; Slotman, Ben J.; Senan, Suresh

    2008-01-01

    Purpose: Respiratory gating can mitigate the effect of tumor mobility in radiotherapy (RT) for lung cancer. Because the tumor is generally not visualized, external surrogates of tumor position are used to trigger respiration-gated RT. We evaluated the suitability of the carina position as a surrogate in respiration-gated RT. Methods and Materials: A total of 30 four-dimensional (4D) computed tomography (CT) scans from 14 patients with lung cancer were retrospectively analyzed. Both uncoached (free breathing) and audio-coached 4D-CT scans were acquired from 9 patients, and 12 uncoached 4D-CT scans were acquired from 5 other patients during a 2-4-week period of stereotactic RT. The repeat scans were co-registered. The carina position was identified on the coronal cut planes in all 4D-CT phases. The correlation between the carina position and the total lung volume for each phase was determined, and the reproducibility of the carina position was studied in the 5 patients with repeat uncoached 4D-CT scans. Results: The mean extent of carina motion in 21 uncoached scans was 5.3 ± 1.6 mm in the craniocaudal (CC), 2.3 ± 1.4 mm in the anteroposterior, and 1.5 ± 0.7 mm in the mediolateral direction. Audio coaching resulted in a twofold increase in carina mobility in all directions. The CC carina position correlated with changes in the total lung volume (R = 0.89 ± 0.14), but the correlation was better for the audio-coached than for the uncoached 4D-CT scans (R = 0.93 ± 0.08 vs. R = 0.85 ± 0.17; paired t test, p = 0.034). Preliminary data from the 5 patients indicated that the CC carina motion correlated better with tumor motion than did the motion of the diaphragm. Conclusions: The CC position of the carina correlated well with the total lung volume, indicating that the carina is a good surrogate for verifying the total lung volume during respiration-gated RT

  1. When are false-positive and false-negative 18F'FDG PET scans really false?

    International Nuclear Information System (INIS)

    Binns, D.S.; Hicks, R.J.; Fawcett, M.E.

    1999-01-01

    Full text: A 61-year-old male presented with locally advanced squamous cell carcinoma of the base of tongue. In the absence of wider metastatic disease on conventional staging, he was enrolled in a phase I, dose escalation chemoradiotherapy trial. In this study, therapeutic response to radiotherapy combined with cisplatin and a chemotherapeutic agent which specifically targets hypoxic cells (tirapazamine) was evaluated with serial 18 F-FDG PET scans. Baseline 18 F-FDG PET confirmed locally advanced disease, although a previously undetected lower cervical lymph node was identified and included in the radiotherapy portal. Whole-body PET revealed a small metabolically active area adjacent to the right hemidiaphragm. Respiratory gated, high-resolution helical CT failed to find structural evidence of disease and, as a result, the patient was enrolled in the 7 week therapy regime on the assumption that the PET finding was a false-positive result. Repeat 18 F-FDG PET scans at the middle, end and 12 weeks post-treatment showed excellent therapeutic response in the head and neck which was discordant with clinical and CT findings, and resolution of the metabolically active chest lesion. Despite the negative PET scan, persistent clinical and CT evidence of a residual tumour mass suggested a false-negative result and resulted in a neck lymph node dissection. This showed no evidence of malignant cells. Five months following treatment, the patient presented with pleural effusion at the base on the right lung. Subsequent CT scanning showed a small pleural lesion at the site of initial 18 F-FDG uptake. Biopsy confirmed metastatic disease. The apparent transient resolution of 18 F-FDG uptake in the pleural lesion with treatment presumably reflected a combination of reduced metabolic activity and size due to the partial, but not complete, cytotoxic effects of cisplatin. In conclusion, this case emphasizes the importance of pathological review and clinical follow-up in reconciling

  2. Adrenal scan in 17-alpha-hydroxylase deficiency: false indication of adrenal adenoma

    International Nuclear Information System (INIS)

    Shore, R.M.; Lieberman, L.M.; Newman, T.J.; Friedman, A.; Bargman, G.J.

    1981-01-01

    A patient who was thought to have testicular feminization syndrome and primary aldosteronism had an adrenal scan that suggested an adrenal adenoma. After later diagnosis of 17-alpha-hydroxylase deficiency, she was treated with glucocorticoids rather than surgery. Her clinical course and a repeat adrenal scan confirmed she did not have a tumor

  3. 46 CFR 169.831 - Emergency position indicating radio beacon (EPIRB).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Emergency position indicating radio beacon (EPIRB). 169.831 Section 169.831 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS... radio beacon (EPIRB). The master shall ensure that— (a) The EPIRB required in § 169.555 of this...

  4. Whole-body computed tomography in trauma patients: optimization of the patient scanning position significantly shortens examination time while maintaining diagnostic image quality

    Directory of Open Access Journals (Sweden)

    Hickethier T

    2018-05-01

    Full Text Available Tilman Hickethier,1,* Kamal Mammadov,1,* Bettina Baeßler,1 Thorsten Lichtenstein,1 Jochen Hinkelbein,2 Lucy Smith,3 Patrick Sven Plum,4 Seung-Hun Chon,4 David Maintz,1 De-Hua Chang1 1Department of Radiology, University Hospital of Cologne, Cologne, Germany; 2Department of Anesthesiology and Intensive Care Medicine, University Hospital of Cologne, Cologne, Germany; 3Faculty of Medicine, Memorial University of Newfoundland, St. John’s, Canada; 4Department of General, Visceral and Cancer Surgery, University Hospital of Cologne, Cologne, Germany *These authors contributed equally to this work Background: The study was conducted to compare examination time and artifact vulnerability of whole-body computed tomographies (wbCTs for trauma patients using conventional or optimized patient positioning. Patients and methods: Examination time was measured in 100 patients scanned with conventional protocol (Group A: arms positioned alongside the body for head and neck imaging and over the head for trunk imaging and 100 patients scanned with optimized protocol (Group B: arms flexed on a chest pillow without repositioning. Additionally, influence of two different scanning protocols on image quality in the most relevant body regions was assessed by two blinded readers. Results: Total wbCT duration was about 35% or 3:46 min shorter in B than in A. Artifacts in aorta (27 vs 6%, liver (40 vs 8% and spleen (27 vs 5% occurred significantly more often in B than in A. No incident of non-diagnostic image quality was reported, and no significant differences for lungs and spine were found. Conclusion: An optimized wbCT positioning protocol for trauma patients allows a significant reduction of examination time while still maintaining diagnostic image quality. Keywords: CT scan, polytrauma, acute care, time requirement, positioning

  5. Scanning behavior in echolocating common pipistrelle bats (Pipistrellus pipistrellus.

    Directory of Open Access Journals (Sweden)

    Anna-Maria Seibert

    Full Text Available Echolocating bats construct an auditory world sequentially by analyzing successive pulse-echo pairs. Many other mammals rely upon a visual world, acquired by sequential foveal fixations connected by visual gaze saccades. We investigated the scanning behavior of bats and compared it to visual scanning. We assumed that each pulse-echo pair evaluation corresponds to a foveal fixation and that sonar beam movements between pulses can be seen as acoustic gaze saccades. We used a two-dimensional 16 microphone array to determine the sonar beam direction of succeeding pulses and to characterize the three dimensional scanning behavior in the common pipistrelle bat (Pipistrellus pipistrellus flying in the field. We also used variations of signal amplitude of single microphone recordings as indicator for scanning behavior in open space. We analyzed 33 flight sequences containing more than 700 echolocation calls to determine bat positions, source levels, and beam aiming. When searching for prey and orienting in space, bats moved their sonar beam in all directions, often alternately back and forth. They also produced sequences with irregular or no scanning movements. When approaching the array, the scanning movements were much smaller and the beam was moved over the array in small steps. Differences in the scanning pattern at various recording sites indicated that the scanning behavior depended on the echolocation task that was being performed. The scanning angles varied over a wide range and were often larger than the maximum angle measurable by our array. We found that echolocating bats use a "saccade and fixate" strategy similar to vision. Through the use of scanning movements, bats are capable of finding and exploring targets in a wide search cone centered along flight direction.

  6. Arrangement of permanent magnet and reed switches for control rod position indicator of SMART CEDM

    International Nuclear Information System (INIS)

    Yoo, J. Y.; Kim, J. I.; Kim, J. H.; Hur, H.; Jang, M. H.

    2001-01-01

    The reliability and accuracy of the information on control rod position are very important to the reactor safety and the design of the core protection system. A survey on the RSPT(Reed Switch Position Transmitter) type control rod position indication system and its actual implementation in the exiting nuclear power plants in Korea was performed first. The control rod position indicator having the high performance for SMART was developed on the basis of RSPT technology identified through the survey. The arrangement of permanent magnet and reed switches is the most important procedure in the design of control rod position indication. In this study, the characteristics of permanent magnet and reed switches are introduced and the calculation method for arrangement of permanent magnet and reed switch is presented

  7. A comparison between intrastomal 3D ultrasonography, CT scanning and findings at surgery in patients with stomal complaints.

    Science.gov (United States)

    Näsvall, P; Wikner, F; Gunnarsson, U; Rutegård, J; Strigård, K

    2014-10-01

    Since there are no reliable investigative tools for imaging parastomal hernia, new techniques are needed. The aim of this study was to assess the validity of intrastomal three-dimensional ultrasonography (3D) as an alternative to CT scanning for the assessment of stomal complaints. Twenty patients with stomal complaints, indicating surgery, were examined preoperatively with a CT scan in the supine position and 3D intrastomal ultrasonography in the supine and erect positions. Comparison with findings at surgery, considered to be the true state, was made. Both imaging methods, 3D ultrasonography and CT scanning, showed high sensitivity (ultrasound 15/18, CT scan 15/18) and specificity (ultrasound 2/2, CT scan 1/2) when judged by a dedicated radiologist. Corresponding values for interpretation of CT scans in routine clinical practice was for sensitivity 17/18 and for specificity 1/2. 3D ultrasonography has a high validity and is a promising alternative to CT scanning in the supine position to distinguish a bulge from a parastomal hernia.

  8. Tumor scanning with /sup 57/Co-bleomycin

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, S; Hasegawa, Y; Matsuda, Minoru; Ho, T; Doi, O [Osaka Prefectural Center for Adult Diseases (Japan)

    1975-06-01

    The clinical application of /sup 57/Co-bleomycin as a tumor scanning radiopharmaceutical was firstly reported by Nouel and Maeda respectively. The authors conducted studies on the diagnostic significance of this tumor scanning agent and presented the results obtained in 40 patients with malignant and non malignant lesions. Six hours and 24 hours after the injection of 500 ..mu..Ci of /sup 57/Co-bleomycin, scintigrams were taken with a 3-inch scintiscanner. Positive scans were found in 20 out of 36 patients with various malignant tumors. Of 20 patients with lung cancer, positive scans were obtained in 17 cases (85%) and of 6 with breast cancer, 3 cases showed positive scans. False negative scans were obtained in another 10 cases of malignant tumors (3 cases of thyroid carcinoma, 4 cases of hepatoma, and 1 case each of gastric carcinoma, peritoneal carcinomatosis, and reticulum cell sarcoma). Of 4 patients with non malignant disease, one case of pulmonary tuberculosis showed a positive scan. In 8 cases of lung cancer and 6 of breast cancer, the relationship between the size of the excised tumor and the scintigram findings was studied. The smallest tumors detected by scintigram were 2 cm in lung cancer and 3.2 cm in breast cancer.

  9. Evaluation of 111In leukocyte whole body scanning

    International Nuclear Information System (INIS)

    McDougall, I.R.; Baumert, J.E.; Lantieri, R.L.

    1979-01-01

    Indium-111 oxine, polymorphonuclear cells isolated and labeled with 111 In were used for studying abscesses and inflammatory conditions. There were 64 total scans done in 59 patients, 32 male and 27 female, aged 3 to 81 years (average, 51). The original clinical diagnosis was abscess in 33 patients. The whole blood cell scan was abnormal in 12 (36%) of these, and a good clinical correlation was obtained in 11 of the 12. In the 21 with a normal scan, 18 had no evidence of abscess, yielding one false-positive and three false-negative interpretations in the abscess group. Thirteen patients had fever of unknown origin, nine had negative scans and no subsequent evidence of abscess, and four had positive scans with good correlation in three. Acute bone and joint infections were positive on scan (4/4), whereas chronic osteomyelitis was negative (0/2). Three patients with acute myocardial infarction and three of four with subacute bacterial endocarditis had normal scans. All three studies in renal transplant rejection showed positive uptake in the pelvic kidneys. Indium-111 white blood cell scans have proved useful to diagnose or exclude a diagnosis of abscess or inflammatory condition infiltrated with polymorphonuclear leukocytes

  10. LIDAR COMBINED SCANNING UNIT

    Directory of Open Access Journals (Sweden)

    V. V. Elizarov

    2016-11-01

    Full Text Available Subject of Research. The results of lidar combined scanning unit development for locating leaks of hydrocarbons are presented The unit enables to perform high-speed scanning of the investigated space in wide and narrow angle fields. Method. Scanning in a wide angular field is produced by one-line scanning path by means of the movable aluminum mirror with a frequency of 20Hz and amplitude of 20 degrees of swing. Narrowband scanning is performed along a spiral path by the deflector. The deflection of the beam is done by rotation of the optical wedges forming part of the deflector at an angle of ±50. The control function of the scanning node is performed by a specialized software product written in C# programming language. Main Results. This scanning unit allows scanning the investigated area at a distance of 50-100 m with spatial resolution at the level of 3 cm. The positioning accuracy of the laser beam in space is 15'. The developed scanning unit gives the possibility to browse the entire investigated area for the time not more than 1 ms at a rotation frequency of each wedge from 50 to 200 Hz. The problem of unambiguous definition of the beam geographical coordinates in space is solved at the software level according to the rotation angles of the mirrors and optical wedges. Lidar system coordinates are determined by means of GPS. Practical Relevance. Development results open the possibility for increasing the spatial resolution of scanning systems of a wide range of lidars and can provide high positioning accuracy of the laser beam in space.

  11. Indicators chest rheography at swimmers at rest and after exercise in different body positions

    Directory of Open Access Journals (Sweden)

    Mariya Sinyugina

    2014-12-01

    Full Text Available Purpose: Study of chest rheography for skilled swimmers when the dosage of physical activity in different body positions. Materials and Methods: the study involved 20 qualified swimmers for middle and long distance. Results: studies changes rheographic indicators from qualified swimmers in response to exercise in different positions of the body showed a clear dependence of the structure and functional hemodynamic changes the position of the body in which the exercise is carried out. Conclusions: found that when evaluating the success of readiness of swimmers and planning training loads must be based on indicators of physical performance obtained during exercise in a horizontal position of the body.

  12. Side-Scan Sonar Image Mosaic Using Couple Feature Points with Constraint of Track Line Positions

    Directory of Open Access Journals (Sweden)

    Jianhu Zhao

    2018-06-01

    Full Text Available To obtain large-scale seabed surface image, this paper proposes a side-scan sonar (SSS image mosaic method using couple feature points (CFPs with constraint of track line positions. The SSS geocoded images are firstly used to form a coarsely mosaicked one and the overlapping areas between adjacent strip images can be determined based on geographic information. Inside the overlapping areas, the feature point (FP detection and registration operation are adopted for both strips. According to the detected CFPs and track line positions, an adjustment model is established to accommodate complex local distortions as well as ensure the global stability. This proposed method effectively solves the problem of target ghosting or dislocation and no accumulated errors arise in the mosaicking process. Experimental results show that the finally mosaicked image correctly reflects the object distribution, which is meaningful for understanding and interpreting seabed topography.

  13. Scanning Tunneling Microscope For Use In Vacuum

    Science.gov (United States)

    Abel, Phillip B.

    1993-01-01

    Scanning tunneling microscope with subangstrom resolution developed to study surface structures. Although instrument used in air, designed especially for use in vacuum. Scanning head is assembly of small, mostly rigid components made of low-outgassing materials. Includes coarse-positioning mechanical-translation stage, on which specimen mounted by use of standard mounting stub. Tunneling tip mounted on piezoelectric fine-positioning tube. Application of suitable voltages to electrodes on piezoelectric tube controls scan of tunneling tip across surface of specimen. Electronic subsystem generates scanning voltages and collects data.

  14. Renal mobility during uncoached quiet respiration: An analysis of 4DCT scans

    International Nuclear Information System (INIS)

    Soernsen de Koste, John R. van; Senan, Suresh; Kleynen, Catharina E.; Slotman, Ben J.; Lagerwaard, Frank J.

    2006-01-01

    Purpose: Data on organ mobility is required for optimizing radiotherapy. Renal mobility was studied in four-dimensional computed tomography (4DCT) scans acquired during uncoached respiration. Methods and Materials: The 4DCT scans of 54 patients, in whom at least the upper pole of both kidneys were visualized in all 10 respiratory phases, were analyzed. Scans were performed on a 16-slice CT scanner (slice index and reconstruction, 2.5 mm) during quiet, uncoached respiration. Mobility of the renal apex was evaluated in all patients by use of the z-position on CT slices. Reproducibility of mobility was studied in 8 patients who underwent 1 or 2 repeat 4DCT scans. Results: Mobility was predominantly craniocaudal, with a mean of 9.8 mm for the left kidney and 9.0 mm for the right kidney. Large interpatient variations were observed that ranged from 2.5 to 30 mm (left) and 2.5 to 20 mm (right), and mobility of 1 kidney did not predict for mobility of the contralateral organ. Reproducibility of renal mobility and position at end-expiration was poor, with positional variations in repeat scans appearing to correlate with changes in the amplitude of respiratory waveform and total lung volume. Conclusions: Large interpatient variations in renal movement occur during uncoached respiration, which indicates that respiratory coaching is useful for 4DCT imaging and treatment delivery

  15. Social position and health in old age: the relevance of different indicators of social position

    DEFF Research Database (Denmark)

    Avlund, Kirsten; Holstein, Bjørn E; Osler, Merete

    2003-01-01

    for men and women. In men the odds ratios of housing tenure on four health variables were strong and unaffected by education and occupation while in women the odds ratios of income on three health variables were strong and unaffected by education and occupation. CONCLUSION: This study demonstrates strong......AIMS: An analysis was undertaken to investigate social inequalities in health among old men and women in relation to five indicators of social position. METHODS: The study is based on a population-based cross-sectional survey among 748 75-year-old men and women, which was performed as clinical......, consistent associations between variables of material wealth indicators and various measures of health among 75-year-old men and women....

  16. Economic evaluation of reprocessing. Indicative US position

    International Nuclear Information System (INIS)

    1979-05-01

    This paper, which also appears as an Appendix to the final Working Group 4 report, forms part of the overall economic assessment of reprocessing. The indicative national position and illustrative ''phase diagram'' for the United States is presented. The prospective costs of nuclear power are given for four equilibrium modes of LWR operation: once-through, 15% and 25% improved once-through and thermal recycle. For a particular representative choice of fuel cycle parameters the economic cross over at which thermal recycle becomes economic relative to a 15% improved once-through cycle is above 100/lb U 3 O 8 . Thus the US believes that for the next several decades there is no economic incentive for thermal recycle. As a planning guide the US considers that the fast reactor will not become commercialised in the US before the year 2020

  17. Bone scanning as a routine examination of patients with mammary carcinoma; a critical consideration. [Preoperative scanning

    Energy Technology Data Exchange (ETDEWEB)

    Heslinga, J M; Pauwels, E K.J.; Zwaveling, A [Rijksuniversiteit Leiden (Netherlands). Academisch Ziekenhuis

    1982-06-05

    The usefulness of bone scanning as a routine examination was evaluated in 136 female patients with mammary carcinoma of whom 81 were staged as Columbia A and 55 as Columbia B/C. The preoperative bone scanning was positive in only 4 patients (2.9%). Consequently, bone scanning is no longer performed in the authors clinic for the preoperative detection of skeletal metastases. Bone scanning as a routine examination at 6-month intervals does not appear to be useful for the first 4 years of the follow-up, either. Most of the patients with a positive bone scan displayed other signs of skeletal metastases at the same time, such as ostealgia and a raised serum alkaline phosphatase level. Further increase of the frequency of bone scanning during the follow-up period would increase the costs considerably, almost prohibitively, even apart from the question whether such a measure might indeed significantly influence the patient's prognosis. The authors conclude that bone scanning should only be performed on the basis of the anamnesis, physical and laboratory findings, both prior to operation and during the follow-up period.

  18. Codification of scan path parameters and development of perimeter scan strategies for 3D bowl-shaped laser forming

    Science.gov (United States)

    Tavakoli, A.; Naeini, H. Moslemi; Roohi, Amir H.; Gollo, M. Hoseinpour; Shahabad, Sh. Imani

    2018-01-01

    In the 3D laser forming process, developing an appropriate laser scan pattern for producing specimens with high quality and uniformity is critical. This study presents certain principles for developing scan paths. Seven scan path parameters are considered, including: (1) combined linear or curved path; (2) type of combined linear path; (3) order of scan sequences; (4) the position of the start point in each scan; (5) continuous or discontinuous scan path; (6) direction of scan path; and (7) angular arrangement of combined linear scan paths. Regarding these path parameters, ten combined linear scan patterns are presented. Numerical simulations show continuous hexagonal, scan pattern, scanning from outer to inner path, is the optimized. In addition, it is observed the position of the start point and the angular arrangement of scan paths is the most effective path parameters. Also, further experimentations show four sequences due to creat symmetric condition enhance the height of the bowl-shaped products and uniformity. Finally, the optimized hexagonal pattern was compared with the similar circular one. In the hexagonal scan path, distortion value and standard deviation rather to edge height of formed specimen is very low, and the edge height despite of decreasing length of scan path increases significantly compared to the circular scan path. As a result, four-sequence hexagonal scan pattern is proposed as the optimized perimeter scan path to produce bowl-shaped product.

  19. Accurate identification of ALK positive lung carcinoma patients: novel FDA-cleared automated fluorescence in situ hybridization scanning system and ultrasensitive immunohistochemistry.

    Directory of Open Access Journals (Sweden)

    Esther Conde

    Full Text Available BACKGROUND: Based on the excellent results of the clinical trials with ALK-inhibitors, the importance of accurately identifying ALK positive lung cancer has never been greater. However, there are increasing number of recent publications addressing discordances between FISH and IHC. The controversy is further fuelled by the different regulatory approvals. This situation prompted us to investigate two ALK IHC antibodies (using a novel ultrasensitive detection-amplification kit and an automated ALK FISH scanning system (FDA-cleared in a series of non-small cell lung cancer tumor samples. METHODS: Forty-seven ALK FISH-positive and 56 ALK FISH-negative NSCLC samples were studied. All specimens were screened for ALK expression by two IHC antibodies (clone 5A4 from Novocastra and clone D5F3 from Ventana and for ALK rearrangement by FISH (Vysis ALK FISH break-apart kit, which was automatically captured and scored by using Bioview's automated scanning system. RESULTS: All positive cases with the IHC antibodies were FISH-positive. There was only one IHC-negative case with both antibodies which showed a FISH-positive result. The overall sensitivity and specificity of the IHC in comparison with FISH were 98% and 100%, respectively. CONCLUSIONS: The specificity of these ultrasensitive IHC assays may obviate the need for FISH confirmation in positive IHC cases. However, the likelihood of false negative IHC results strengthens the case for FISH testing, at least in some situations.

  20. Indications for computerized tomography in the case of headache

    International Nuclear Information System (INIS)

    Huk, W.J.

    1987-01-01

    Of the large number of patients with headache only very few suffer from an intracranial tumor. On the other hand, brain tumors may grow silently for a long period of time. Clinical analysis of patients with headache has demonstrated that a CT-scan is not indicated in cases where an adequate cause can be found and when the headache disappears together with the underlaying cause in a reasonable amount of time. A CT-scan, however, should be performed when an adequate cause is missing, when the headache recurs with increasing frequency, intensity and duration, when it is accentuated in the morning and in certain positions, and when it is associated with personality chances, dizziness and blurred vision. In chronic headache a CT-scan is indicated when a change in the character of the headache and its various qualities (location, frequency and duration of attacks, temporal coincidence etc.) can be detected. A thorough history, including the family history, of the complains together with an accurate clinical examination will deliver the criteria to avoid unnecessary CT-scanning. (orig.) [de

  1. Design of magnetic flux concentrator of permancent magnet for control rod position indicator of SMART CEDM

    International Nuclear Information System (INIS)

    Yoo, J. Y.; Kim, J. H.; Hur, H.; Kim, J. I.

    2002-01-01

    The reliability and accuracy of the information on control rod position are very important to the reactor safety and the design of the core protection system. A survey on the RSPT(Reed Switch Position Transmitter) type control rod position indication system and its actual implementation in the exiting nuclear power plants in Korea was performed first. The control rod position indicator having the high performance for SMART was developed on the basis of RSPT technology identified through the survey. The arrangement of permanent magnet and reed switches is the most important procedure in the design of control rod position indication. In this study, the magnetic flux concentrator of permanent magnet is introduced and the calculation method for effective flux area for reed switch is presented

  2. Arterial scan versus radiographic angiography in detection of shallow arterial ulcers

    International Nuclear Information System (INIS)

    Pollak, E.W.; Webber, M.M.; Cragin, M.D.; Wolfman, E.F. Jr.

    1977-01-01

    A comparison of 99m-technetium albumin aggregated arterial scan and radiographic angiography for detection of shallow intimal carotid artery ulcerations was made in a series of 12 anesthetized dogs, having a total of 16 acute arterial ulcerations. Radiographic angiography showed positive findings related to presence of stenosis or mural thrombosis in 12 instances. Direct visualization of ulceration was only exceptionally encountered. Arterial scan detected 14 of 16 intimal ulcers. The radionuclide method was reliable even in absence of stenosis or when only minimal mural thrombosis was present. Moreover, autopsy scan of the isolated arterial segments detected all 16 intimal lesions. These results indicate that the arterial scan was a more reliable method for detection of shallow arterial ulcers in this experimental model than radiographic angiography, especially when arterial lumen stenosis or mural thrombosis was minimal or absent

  3. Translate rotate scanning method for X-ray imaging

    International Nuclear Information System (INIS)

    Eberhard, J.W.; Kwog Cheong Tam.

    1990-01-01

    Rapid x-ray inspection of objects larger than an x-ray detector array is based on a translate rotate scanning motion of the object related to the fan beam source and detector. The scan for computerized tomography imaging is accomplished by rotating the object through 360 degrees at two or more positions relative to the source and detector array, in moving to another position the object is rotated and the object or source and detector are translated. A partial set of x-ray data is acquired at every position which are combined to obtain a full data set for complete image reconstruction. X-ray data for digital radiography imaging is acquired by scanning the object vertically at a first position at one view angle, rotating and translating the object relative to the source and detector to a second position, scanning vertically, and so on to cover the object field of view, and combining the partial data sets. (author)

  4. A High Rigidity and Precision Scanning Tunneling Microscope with Decoupled XY and Z Scans.

    Science.gov (United States)

    Chen, Xu; Guo, Tengfei; Hou, Yubin; Zhang, Jing; Meng, Wenjie; Lu, Qingyou

    2017-01-01

    A new scan-head structure for the scanning tunneling microscope (STM) is proposed, featuring high scan precision and rigidity. The core structure consists of a piezoelectric tube scanner of quadrant type (for XY scans) coaxially housed in a piezoelectric tube with single inner and outer electrodes (for Z scan). They are fixed at one end (called common end). A hollow tantalum shaft is coaxially housed in the XY -scan tube and they are mutually fixed at both ends. When the XY scanner scans, its free end will bring the shaft to scan and the tip which is coaxially inserted in the shaft at the common end will scan a smaller area if the tip protrudes short enough from the common end. The decoupled XY and Z scans are desired for less image distortion and the mechanically reduced scan range has the superiority of reducing the impact of the background electronic noise on the scanner and enhancing the tip positioning precision. High quality atomic resolution images are also shown.

  5. A High Rigidity and Precision Scanning Tunneling Microscope with Decoupled XY and Z Scans

    Directory of Open Access Journals (Sweden)

    Xu Chen

    2017-01-01

    Full Text Available A new scan-head structure for the scanning tunneling microscope (STM is proposed, featuring high scan precision and rigidity. The core structure consists of a piezoelectric tube scanner of quadrant type (for XY scans coaxially housed in a piezoelectric tube with single inner and outer electrodes (for Z scan. They are fixed at one end (called common end. A hollow tantalum shaft is coaxially housed in the XY-scan tube and they are mutually fixed at both ends. When the XY scanner scans, its free end will bring the shaft to scan and the tip which is coaxially inserted in the shaft at the common end will scan a smaller area if the tip protrudes short enough from the common end. The decoupled XY and Z scans are desired for less image distortion and the mechanically reduced scan range has the superiority of reducing the impact of the background electronic noise on the scanner and enhancing the tip positioning precision. High quality atomic resolution images are also shown.

  6. Evaluation of /sup 111/In leukocyte whole body scanning

    Energy Technology Data Exchange (ETDEWEB)

    McDougall, I.R.; Baumert, J.E.; Lantieri, R.L.

    1979-11-01

    Indium-111 oxine, polymorphonuclear cells isolated and labeled with /sup 111/In were used for studying abscesses and inflammatory conditions. There were 64 total scans done in 59 patients, 32 male and 27 female, aged 3 to 81 years (average, 51). The original clinical diagnosis was abscess in 33 patients. The whole blood cell scan was abnormal in 12 (36%) of these, and a good clinical correlation was obtained in 11 of the 12. In the 21 with a normal scan, 18 had no evidence of abscess, yielding one false-positive and three false-negative interpretations in the abscess group. Thirteen patients had fever of unknown origin, nine had negative scans and no subsequent evidence of abscess, and four had positive scans with good correlation in three. Acute bone and joint infections were positive on scan (4/4), whereas chronic osteomyelitis was negative (0/2). Three patients with acute myocardial infarction and three of four with subacute bacterial endocarditis had normal scans. All three studies in renal transplant rejection showed positive uptake in the pelvic kidneys. Indium-111 white blood cell scans have proved useful to diagnose or exclude a diagnosis of abscess or inflammatory condition infiltrated with polymorphonuclear leukocytes.

  7. Exact cone beam CT with a spiral scan

    International Nuclear Information System (INIS)

    Tam, K.C.; Samarasekera, S.; Sauer, F.

    1998-01-01

    A method is developed which makes it possible to scan and reconstruct an object with cone beam x-rays in a spiral scan path with area detectors much shorter than the length of the object. The method is mathematically exact. If only a region of interest of the object is to be imaged, a top circle scan at the top level of the region of interest and a bottom circle scan at the bottom level of the region of interest are added. The height of the detector is required to cover only the distance between adjacent turns in the spiral projected at the detector. To reconstruct the object, the Radon transform for each plane intersecting the object is computed from the totality of the cone beam data. This is achieved by suitably combining the cone beam data taken at different source positions on the scan path; the angular range of the cone beam data required at each source position can be determined easily with a mask which is the spiral scan path projected on the detector from the current source position. The spiral scan algorithm has been successfully validated with simulated cone beam data. (author)

  8. Left ventricular filling rate change as an earlier indicator than ejection fraction of chemotherapeutic cardiotoxicity in cancer paptents' nuclear medicine MUGA scans

    International Nuclear Information System (INIS)

    Miko, T.G.

    2004-01-01

    According to Wang Siegel has long suggested that an earlier indicator of damage to the hearts of cancer patients undergoing potentially cardiotoxic chemotherapy could be change in the left ventricular filling rate (LVFT) rather than dependence on the left ventricular ejection fraction (LVEF) as a measure for when to discontinue chemotherapy. Currently ejection fraction obtained by performing the nuclear medicine MUGA scan is the gold standard for determining further treatment of patients with these cardiotoxic agents. We are seeking to see if changes in filling rate (LVFR) are an earlier indicator of cardiotoxicity by performing a retrospective analysis of MUGA scans performed at our facility pre- and post-chemotherapy and performing a statistical analysis of changes in ejection fraction us filling rate in patients known to have cardiotoxic changes due to chemotherapy. (authors)

  9. Prosthetic graft infection: limitations of indium white blood cell scanning

    International Nuclear Information System (INIS)

    Brunner, M.C.; Mitchell, R.S.; Baldwin, J.C.; James, D.R.; Olcott, C. IV; Mehigan, J.T.; McDougall, I.R.; Miller, D.C.

    1986-01-01

    The lack of a rapid, noninvasive, and accurate method to confirm or rule out prosthetic graft infection continues to constitute a compelling and vexing clinical problem. A host of adjunctive diagnostic techniques has been used in the past, but early promising results subsequently have usually not yielded acceptable sensitivity (reflecting false negatives) and specificity (reflecting false positive) data. White blood cell (WBC) indium 111 scanning has recently been added to this list. The utility and accuracy of 111 In WBC scans were assessed by retrospective review of WBC scan results in 70 patients undergoing evaluation for possible prosthetic graft infection over a 7-year period. Operative and autopsy data (mean follow-up, 18 months for survivors with negative scans) were used to confirm the 22 positive, 45 negative, and three equivocal WBC scans. The false positive rate (+/- 70% confidence limits) was 36% +/- 6% (n = 8) among the 22 patients with positive scans (44% +/- 6% [11 of 25] if the three equivocal scans are included as false positive), yielding a specificity of 85% +/- 5% and an overall accuracy rate of 88% +/- 4% (80% +/- 5% and 84% +/- 5%, respectively, if the three equivocal cases are considered as false positive). All three patients with equivocal scans ultimately were judged not to have prosthetic graft infection. As implied by the high accuracy rate, the sensitivity of the test was absolute (100% [14 of 14]); there were no false negative results

  10. Analysis of magnetic field and hysteresis of reed switches for control rod position indicator of SMART CEDM

    International Nuclear Information System (INIS)

    Yoo, J. W.; Kim, J. H.; Heo, H.; Kim, J. I.; Jang, M. H.

    2002-01-01

    The reliability and accuracy of the information on control rod position are very important to the reactor safety and the design of the core protection system. A survey on the RSPT(Reed Switch Position Transmitter) type control rod position indication system and its actual implementation in the exiting nuclear power plants in Korea was performed first. The control rod position indicator having the high performance for SMART was developed on the basis of RSPT technology identified through the survey. The hysteresis of reed switches is one of the important factors in a repeat accuracy of control rod position indication. In this study, the hysteresis of reed switches is introduced and the design method using the magnetic analysis of reed switches in presented

  11. Positive indium-III bone marrow scan in metastatic breast carcinoma. Case report

    International Nuclear Information System (INIS)

    LaManna, M.M.; Hyzinski, M.; Swami, V.K.; Parker, J.A.

    1984-01-01

    Indium is generally presumed to localize in the bone marrow within the erythroid cell line. Fibrosis, inflammation, lymphoma, extended field radiation, chemotherapy, or combinations of both treatment modalities generally depress the uptake of indium by the marrow in a complex fashion. We report a case of metastatic breast carcinoma and pancytopenia in which the In-111 scan appeared qualitatively similar to a Tc-99m MDP bone scan. Findings were confirmed by bone marrow biopsy

  12. Scan path entropy and Arrow plots: Capturing scanning behavior of multiple observers

    Directory of Open Access Journals (Sweden)

    Ignace T C Hooge

    2013-12-01

    Full Text Available Designers of visual communication material want their material to attract and retain attention. In marketing research, heat maps, dwell time, and time to AOI first hit are often used as evaluation parameters. Here we present two additional measures 1 scan path entropy to quantify gaze guidance and 2 the arrow plot to visualize the average scan path. Both are based on string representations of scan paths. The latter also incorporates transition matrices and time required for 50% of the observers to first hit AOIs (T50. The new measures were tested in an eye tracking study (48 observers, 39 advertisements. Scan path entropy is a sensible measure for gaze guidance and the new visualization method reveals aspects of the average scan path and gives a better indication in what order global scanning takes place.

  13. Differentiation of osteomyelitis and infarction in sickle-cell hemoglobinopathies using combined bone-marrow and gallium scanning

    International Nuclear Information System (INIS)

    Hatfield, M.K.; Kahn, C.E.; Ryan, J.W.; Martin, W.B.

    1986-01-01

    The clinical records and scintigrams of patients with sickle cell hemoglobinopathies in whom acute symptoms developed suggestive of possible osteomyelitis and who had undergone sequential Tc-99m bone marrow scans and gallium scintigraphy of the affected sites were reviewed. Osteomyelitis was correctly diagnosed in six of 18 cases when gallium was focally increased relative to a site of decreased or absent bone marrow activity. Of 12 episodes of infarction, both studies showed focally decreased activity in a concordant manner in 11. The remaining, false-positive study indicated slightly increased gallium in 11. The remaining, false-positive indicated slightly increased gallium concentration at a site of decreased bone marrow activity. Overall, a protocol of sequential Tc-99m bone marrow scans and gallium scintigraphy is an effective means of distinguishing osteomyelitis from infarction in patients with sickle cell hemoglobinopathies

  14. Fault tolerant, multiplexed control rod position detection and indication system for nuclear power plants

    International Nuclear Information System (INIS)

    Dufek, W.L.; Jelovich, J.J.; Neuner, J.A.

    1977-01-01

    The majority of Westinghouse nuclear plants placed in service thus far have incorporated a Rod Position Indication system based upon an analog design philosophy. This system, while meeting all functional and accuracy requirements, has proven somewhat cumbersome, particularly in the area of initial field calibration and maintenance. This paper describes a new Digital Rod Position Indication system (DRPI) developed for use with pressurized water reactors. The system is based upon a digital design philosophy and meets all previous design constraints and environmental requirements. Further, fault tolerance, improved accuracy, interference from adjacent rods and the elimination of adjustments and calibration has been provided

  15. Gallium scans in myasthenia gravis

    International Nuclear Information System (INIS)

    Swick, H.M.; Preston, D.F.; McQuillen, M.P.

    1976-01-01

    A study was conducted to determine whether 67 Ga scans could be used for the detection of thymomas and to investigate the activity of the thymus gland in patients with myasthenia gravis. Scans of the anterior mediastinum proved to be a reliable way to detect thymomas. The scans were positive in eight patients including three with myasthenia gravis and histologically proved thymomas, three others with severe myasthenia gravis and thymic tumors, and two with histologically proved thymomas not associated with myasthenia. Activity on 67 Ga scans was not directly related to the increased activity of the thymus gland that is presumed to be associated with myasthenia gravis

  16. Gallium scans in myasthenia gravis

    Energy Technology Data Exchange (ETDEWEB)

    Swick, H.M. (Univ. of Kentucky, Lexington); Preston, D.F.; McQuillen, M.P.

    1976-01-01

    A study was conducted to determine whether /sup 67/Ga scans could be used for the detection of thymomas and to investigate the activity of the thymus gland in patients with myasthenia gravis. Scans of the anterior mediastinum proved to be a reliable way to detect thymomas. The scans were positive in eight patients including three with myasthenia gravis and histologically proved thymomas, three others with severe myasthenia gravis and thymic tumors, and two with histologically proved thymomas not associated with myasthenia. Activity on /sup 67/Ga scans was not directly related to the increased activity of the thymus gland that is presumed to be associated with myasthenia gravis. (HLW)

  17. 241-AN-A valve pit manifold valves and position indication acceptance test procedure

    Energy Technology Data Exchange (ETDEWEB)

    VANDYKE, D.W.

    1999-08-25

    This document describes the method used to test design criteria for gear actuated ball valves installed in 241-AN-A Valve Pit located at 200E Tank Farms. The purpose of this procedure is to demonstrate the following: Equipment is properly installed, labeled, and documented on As-Built drawings; New Manifold Valves in the 241-AN-A Valve Pit are fully operable using the handwheel of the valve operators; New valve position indicators on the valve operators will show correct valve positions; New valve position switches will function properly; and New valve locking devices function properly.

  18. The utility of bone scans in rheumatology

    International Nuclear Information System (INIS)

    Duncan, I.; Dorai-Raj, A.; Khoo, K.; Tymans, K.; Brook, A.

    1997-01-01

    Full text: Introduction: Bone scans are the commonest diagnostic imaging services requested by Australian rheumatologists. Medicare figures suggest that an average rheumatologist orders about $50 000 (AUS) of bone scans annually. Aims: To ascertain the reasons why rheumatologists request bone scans and how it affects their patient management. Methods: A two-part prospective survey was administered before and after every bone scan ordered by four rheumatologists over a six-month period in 1996. Results: A total of 136 bone scans were requested (66.2% whole body; 33.8% regional; 6% SPECT). The primary indications for scanning were (1) to confirm a clinical diagnosis (38%); (2) to exclude a diagnosis (34%); (3) to localize site of pain (17%); and (4) to assist in management (6%). The common diseases that rheumatologists were attempting to confirm/exclude with bone scanning were inflammatory arthritis, malignancy, and fracture. However, the commonest provisional and final diagnosis was soft tissue rheumatism (18%) followed by inflammatory arthritis (15%) and osteoarthritis (11%). In 24% of patients with a provisional diagnosis of soft tissue rheumatism the diagnosis was changed by the bone scan. The scan was successful in excluding a diagnosis in 88 per cent where this was the primary indication for the test. It was successful in confirming a diagnosis in 79 per cent where this was the primary indication. In 32 per cent the bone scan altered the clinical diagnosis and in 43 per cent it altered management. The bone scan result prevented further investigations in 60 per cent. Conclusions: The commonest pre-scan and post-scan diagnosis is soft tissue rheumatism. Rheumatologists predominantly request bone scanning to confirm or exclude their clinical suspicion of inflammatory arthritis, malignancy, and fracture. Bone scans were successful in achieving these objectives in at least 79 per cent of cases

  19. Impact of Audio-Coaching on the Position of Lung Tumors

    International Nuclear Information System (INIS)

    Haasbeek, Cornelis J.A.; Spoelstra, Femke; Lagerwaard, Frank J.; Soernsen de Koste, John R. van; Cuijpers, Johan P.; Slotman, Ben J.; Senan, Suresh

    2008-01-01

    Purpose: Respiration-induced organ motion is a major source of positional, or geometric, uncertainty in thoracic radiotherapy. Interventions to mitigate the impact of motion include audio-coached respiration-gated radiotherapy (RGRT). To assess the impact of coaching on average tumor position during gating, we analyzed four-dimensional computed tomography (4DCT) scans performed both with and without audio-coaching. Methods and Materials: Our RGRT protocol requires that an audio-coached 4DCT scan is performed when the initial free-breathing 4DCT indicates a potential benefit with gating. We retrospectively analyzed 22 such paired scans in patients with well-circumscribed tumors. Changes in lung volume and position of internal target volumes (ITV) generated in three consecutive respiratory phases at both end-inspiration and end-expiration were analyzed. Results: Audio-coaching increased end-inspiration lung volumes by a mean of 10.2% (range, -13% to +43%) when compared with free breathing (p = 0.001). The mean three-dimensional displacement of the center of ITV was 3.6 mm (SD, 2.5; range, 0.3-9.6mm), mainly caused by displacement in the craniocaudal direction. Displacement of ITV caused by coaching was more than 5 mm in 5 patients, all of whom were in the subgroup of 9 patients showing total tumor motion of 10 mm or more during both coached and uncoached breathing. Comparable ITV displacements were observed at end-expiration phases of the 4DCT. Conclusions: Differences in ITV position exceeding 5 mm between coached and uncoached 4DCT scans were detected in up to 56% of mobile tumors. Both end-inspiration and end-expiration RGRT were susceptible to displacements. This indicates that the method of audio-coaching should remain unchanged throughout the course of treatment

  20. Automated surface-scanning detection of pathogenic bacteria on fresh produce

    Science.gov (United States)

    Horikawa, Shin; Du, Songtao; Liu, Yuzhe; Chen, I.-Hsuan; Xi, Jianguo; Crumpler, Michael S.; Sirois, Donald L.; Best, Steve R.; Wikle, Howard C.; Chin, Bryan A.

    2017-05-01

    This paper investigates the effects of surface-scanning detector position on the resonant frequency and signal amplitude of a wireless magnetoelastic (ME) biosensor for direct pathogen detection on solid surfaces. The experiments were conducted on the surface of a flat polyethylene (PE) plate as a model study. An ME biosensor (1 mm × 0.2 mm × 30 μm) was placed on the PE surface, and a surface-scanning detector was brought close and aligned to the sensor for wireless resonant frequency measurement. The position of the detector was accurately controlled by using a motorized three-axis translation system (i.e., controlled X, Y, and Z positions). The results showed that the resonant frequency variations of the sensor were -125 to +150 Hz for X and Y detector displacements of +/-600 μm and Z displacements of +100 to +500 μm. These resonant frequency variations were small compared to the sensor's initial resonant frequency (< 0.007% of 2.2 MHz initial resonant frequency) measured at the detector home position, indicating high accuracy of the measurement. In addition, the signal amplitude was, as anticipated, found to decrease exponentially with increasing detection distance (i.e., Z distance). Finally, additional experiments were conducted on the surface of cucumbers. Similar results were obtained.

  1. Three phase bone scan , Ga-67 and Tc-99m nanocoll scan in detection of osteomyelitis caused by war injuries

    International Nuclear Information System (INIS)

    Banek, T.; Reljica-Kostic, Z.; Kurnik, G.

    1994-01-01

    Thirty three injured soldiers were surgically treated because of pierce wounds of extremities. Treatment was either osteosynthesis or external fixation. Two to four weeks post treatment clinical signs of osteomyelitis appeared. X-ray was negative in all patients. Three-phase bone scan was performed in order to establish diagnosis. Bone scan was positive in all patients. For 11 patients only bone scan was sufficient for decision of further treatment. In 22 patients Ga-67 or Tc-99m- nanocoll or both examinations were performed on surgeon's request. In 2 patients out of 5 with additional Ga-67 scan, Ga-67 scan showed more lesions than it was seen on bone scan. In 3 patients out of 5 with additional Tc-99m-nanocoll scan, Tc-99m-nanocoll scan showed more lesions than it was seen on bone scan. In 12 patients with positive bone scan and negative or unclear Ga-67, Tc-99m-nanocoll scan was performed. In 5 out of 12 patients Tc-99m- nanocoll scan established diagnosis in others confirmed finding on bone and Ga-67 scan. Our results showed that in one third of our causes bone scan was sufficient for diagnosing of osteomyelitis caused by war injuries. In selected cases where bone scan was not sufficient for diagnosis and decision for treatment Tc-99m-nanocoll was more sensitive than Ga-67. In our experience three-phase bone scan is more sensitive than Ga-67. In our opinion three-phase bone scan is the method of choice for diagnosing osteomyelitis in war situation with a lot of casualties. (author)

  2. Repeated CT scans in trauma transfers: An analysis of indications, radiation dose exposure, and costs

    International Nuclear Information System (INIS)

    Hinzpeter, Ricarda; Sprengel, Kai; Wanner, Guido A.; Mildenberger, Peter; Alkadhi, Hatem

    2017-01-01

    Highlights: • Repetition of CT in trauma patients occurs relatively often. • Repetition of CT is mainly caused by inadequate image data transfer. • Potentially preventable CT examinations add radiation dose to patients. • Repeated CT is associated with excess costs to the health care system. - Abstract: Objectives: To identify the number of CT scans repeated in acute trauma patients receiving imaging before being referred to a trauma center, to define indications, and to assess radiation doses and costs of repeated CT. Methods: This retrospective study included all adult trauma patients transferred from other hospitals to a Level-I trauma center during 2014. Indications for repeated CT scans were categorized into: inadequate CT image data transfer, poor image quality, repetition of head CT after head injury together with completion to whole-body CT (WBCT), and follow-up of injury known from previous CT. Radiation doses from repeated CT were determined; costs were calculated using a nation-wide fee schedule. Results: Within one year, 85/298 (28.5%) trauma patients were transferred from another hospital because of severe head injury (n = 45,53%) and major body trauma (n = 23;27%) not manageable in the referring hospital, repatriation from a foreign country (n = 14;16.5%), and no ICU-capacity (n = 3;3.5%). Of these 85 patients, 74 (87%) had repeated CT in our center because of inadequate CT data transfer (n = 29;39%), repetition of head CT with completion to WBCT (n = 24;32.5%), and follow-up of known injury (n = 21;28.5%). None occurred because of poor image quality. Cumulative dose length product (DLP) and annual costs of potential preventable, repeated CT (inadequate data transfer) was 631mSv (81′304mGy*cm) and 35′233€, respectively. Conclusion: A considerable number of transferred trauma patients undergo potentially preventable, repeated CT, adding radiation dose to patients and costs to the health care system.

  3. Repeated CT scans in trauma transfers: An analysis of indications, radiation dose exposure, and costs

    Energy Technology Data Exchange (ETDEWEB)

    Hinzpeter, Ricarda, E-mail: Ricarda.Hinzpeter@usz.ch [Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Raemistr. 100, Zurich CH-8091 (Switzerland); Sprengel, Kai, E-mail: Kai.Sprengel@usz.ch [Division of Trauma Surgery, Department of Surgery, University Hospital Zurich, University of Zurich, Raemistr. 100, CH-8091 Zurich (Switzerland); Wanner, Guido A., E-mail: Guido.Wanner@sbk-vs.de [Division of Trauma Surgery, Department of Surgery, University Hospital Zurich, University of Zurich, Raemistr. 100, CH-8091 Zurich (Switzerland); Department of General Surgery, Schwarzwald-Baar Klinikum, University of Freiburg, Klinikstr. 11, D-78052 Villingen-Schwenningen (Germany); Mildenberger, Peter, E-mail: peter.mildenberger@unimedizin-mainz.de [Department of Diagnostic and Interventional Radiology, University Hospital of Mainz, Langenbeckstr. 1, D-55131 Mainz (Germany); Alkadhi, Hatem, E-mail: hatem.alkadhi@usz.ch [Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Raemistr. 100, Zurich CH-8091 (Switzerland)

    2017-03-15

    Highlights: • Repetition of CT in trauma patients occurs relatively often. • Repetition of CT is mainly caused by inadequate image data transfer. • Potentially preventable CT examinations add radiation dose to patients. • Repeated CT is associated with excess costs to the health care system. - Abstract: Objectives: To identify the number of CT scans repeated in acute trauma patients receiving imaging before being referred to a trauma center, to define indications, and to assess radiation doses and costs of repeated CT. Methods: This retrospective study included all adult trauma patients transferred from other hospitals to a Level-I trauma center during 2014. Indications for repeated CT scans were categorized into: inadequate CT image data transfer, poor image quality, repetition of head CT after head injury together with completion to whole-body CT (WBCT), and follow-up of injury known from previous CT. Radiation doses from repeated CT were determined; costs were calculated using a nation-wide fee schedule. Results: Within one year, 85/298 (28.5%) trauma patients were transferred from another hospital because of severe head injury (n = 45,53%) and major body trauma (n = 23;27%) not manageable in the referring hospital, repatriation from a foreign country (n = 14;16.5%), and no ICU-capacity (n = 3;3.5%). Of these 85 patients, 74 (87%) had repeated CT in our center because of inadequate CT data transfer (n = 29;39%), repetition of head CT with completion to WBCT (n = 24;32.5%), and follow-up of known injury (n = 21;28.5%). None occurred because of poor image quality. Cumulative dose length product (DLP) and annual costs of potential preventable, repeated CT (inadequate data transfer) was 631mSv (81′304mGy*cm) and 35′233€, respectively. Conclusion: A considerable number of transferred trauma patients undergo potentially preventable, repeated CT, adding radiation dose to patients and costs to the health care system.

  4. Influence of Peer Social Experiences on Positive and Negative Indicators of Mental Health among High School Students

    Science.gov (United States)

    Suldo, Shannon M.; Gelley, Cheryl D.; Roth, Rachel A.; Bateman, Lisa P.

    2015-01-01

    Modern definitions of complete mental health include both positive and negative indicators of psychological functioning. We examined the associations between peer relationships (victimization and receipt of prosocial acts) and multiple indicators of mental health that represent subjective well-being (i.e., life satisfaction, positive and negative…

  5. Postprocessing Algorithm for Driving Conventional Scanning Tunneling Microscope at Fast Scan Rates.

    Science.gov (United States)

    Zhang, Hao; Li, Xianqi; Chen, Yunmei; Park, Jewook; Li, An-Ping; Zhang, X-G

    2017-01-01

    We present an image postprocessing framework for Scanning Tunneling Microscope (STM) to reduce the strong spurious oscillations and scan line noise at fast scan rates and preserve the features, allowing an order of magnitude increase in the scan rate without upgrading the hardware. The proposed method consists of two steps for large scale images and four steps for atomic scale images. For large scale images, we first apply for each line an image registration method to align the forward and backward scans of the same line. In the second step we apply a "rubber band" model which is solved by a novel Constrained Adaptive and Iterative Filtering Algorithm (CIAFA). The numerical results on measurement from copper(111) surface indicate the processed images are comparable in accuracy to data obtained with a slow scan rate, but are free of the scan drift error commonly seen in slow scan data. For atomic scale images, an additional first step to remove line-by-line strong background fluctuations and a fourth step of replacing the postprocessed image by its ranking map as the final atomic resolution image are required. The resulting image restores the lattice image that is nearly undetectable in the original fast scan data.

  6. Postprocessing Algorithm for Driving Conventional Scanning Tunneling Microscope at Fast Scan Rates

    Directory of Open Access Journals (Sweden)

    Hao Zhang

    2017-01-01

    Full Text Available We present an image postprocessing framework for Scanning Tunneling Microscope (STM to reduce the strong spurious oscillations and scan line noise at fast scan rates and preserve the features, allowing an order of magnitude increase in the scan rate without upgrading the hardware. The proposed method consists of two steps for large scale images and four steps for atomic scale images. For large scale images, we first apply for each line an image registration method to align the forward and backward scans of the same line. In the second step we apply a “rubber band” model which is solved by a novel Constrained Adaptive and Iterative Filtering Algorithm (CIAFA. The numerical results on measurement from copper(111 surface indicate the processed images are comparable in accuracy to data obtained with a slow scan rate, but are free of the scan drift error commonly seen in slow scan data. For atomic scale images, an additional first step to remove line-by-line strong background fluctuations and a fourth step of replacing the postprocessed image by its ranking map as the final atomic resolution image are required. The resulting image restores the lattice image that is nearly undetectable in the original fast scan data.

  7. Where is the place of bone scan in breast cancer?

    International Nuclear Information System (INIS)

    Nowferesti, G. H.; Ghavam Nasiri, M. R.; Anvari, K.

    2002-01-01

    Breast cancer is the most common female cancer in west and in Iran. The incidence in all over the world in year 2000 was 1050000 cases out of which 370000 were dead. General y bone is the most common site of distant. Metastases in beast cancer. Bone scan has an important place in the bone metastases and extent of bone disease and even in the staging and treatment protocol. In study done during 1 year, breast cancer patients and place of bone scan were studied. Every year more than 2000 new patients with cancer are diagnosed and treated in Khorasan state. And more than half of them are treated in Omid Hospital. In the year 2000 a study was done. 1336 new cases were admitted for treatment out of which 164 persons (13%) were breast cancer patients. 100 patients were selected randomly and different factors were studied. How many patients had bone scan and its place in breast cancer? Where is the most common metastatic place and relation with bone scan? The differential diagnosis in positive bone scans and comparing with radiography and patient's clinic were studied. Bone scan is positive in 35% of patients in stage III. Bone is the most common place for distant metastases in breast cancer in patients admitted in Omid hospital in year 2000. Clinical and para clinical study such as radiography and tumour markers were adjusted with bone scan, more in stages III and IV. 39 patients out of 100 studied patients had bone scan. 28 bone scan were adjusted radiologically. In 20 positive bone scan out of 28 patients with metastases 12 patients had bone metastases. Despite 5% positive bone scan in early stages can suggest that bone scan be taken for all patients with breast cancer as a basic step?

  8. Improvement of Diagnostic Accuracy by Standardization in Diuretic Renal Scan

    International Nuclear Information System (INIS)

    Hyun, In Young; Lee, Dong Soo; Lee, Kyung Han; Chung, June Key; Lee, Myung Chul; Koh, Chang Soon; Kim, Kwang Myung; Choi, Hwang; Choi, Yong

    1995-01-01

    We evaluated diagnostic accuracy of diuretic renal scan with standardization in 45 children(107 hydronephrotic kidneys) with 91 diuretic assessments. Sensitivity was 100% specificity was 78%, and accuracy was 84% in 49 hydronephrotic kidneys with standardization. Diuretic renal scan without standardization, sensitivity was 100%, specificity was 38%, and accuracy was 57% in 58 hydronephrotic kidneys. The false-positive results were observed in 25 cases without standardization, and in 8 cases with standardization. In duretic renal scans without standardization, the causes of false-positive results were 10 early injection of lasix before mixing of radioactivity in loplsty, 6 extrarenal pelvis, and 3 immature kidneys of false-positive results were 2 markedly dilated systems postpyeloplsty, 2 etrarenal pevis, 1 immature kidney of neonate , and 2 severe renal dysfunction, 1 vesicoureteral, reflux. In diuretic renal scan without standardization the false-positive results by inadequate study were common, but false-positive results by inadequate study were not found after standardization. The false-positive results by dilated pelvo-calyceal systems postpyeloplsty, extrarenal pelvis, and immature kidneys of, neonates were not dissolved after standardization. In conclusion, diagnostic accuracy of diuretic renal scan with standardization was useful in children with renal outflow tract obstruction by improving specificity significantly.

  9. Tomographic scanning apparatus

    International Nuclear Information System (INIS)

    Abele, M.

    1983-01-01

    A computerized tomographic scanning apparatus suitable for diagnosis and for improving target identification in stereotactic neurosurgery is described. It consists of a base, a source of penetrating energy, a detector which produces scanning signals and detector positioning means. A frame with top and bottom arms secures the detector and source to the top and bottom arms respectively. A drive mechanism rotates the frame about an axis along which the frame may also be moved. Finally, the detector may be moved relative to the bottom arm in a direction contrary to the rotation of the frame. (U.K.)

  10. Clinical Usefulness of F-18 FDG PET/CT in papillary thyroid cancer with negative radioiodine scan and elevated thyroglobulin level or positive anti-thyroglobulin antibody

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Su Jung; Jung, Kyung Pyo; Lee, Sun Seong; Park, Yun Soo; Lee, Seok Mo [Dept. of Nuclear Medicine, Busan Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of); Bae, Sang Kyun [Dept. of Nuclear Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of)

    2016-06-15

    Elevated thyroglobulin (Tg) levels, along with a negative radioiodine scan, present a clinical problem for the diagnosis of recurrence in papillary thyroid cancer (PTC) patients. The purpose of this study was to assess (1) the usefulness of 18F-fluorodeoxyglucose (F-18 FDG) positron emission tomography (PET)/computed tomography (CT) for PTC patients with negative diagnostic radioiodine scan and elevated serum Tg level or positive anti-thyroglobulin antibody (TgAb), and (2) the effect of endogenous thyroid stimulating hormone (TSH) stimulation (ETS) on detecting recurrence in these circumstances. Eighty-four patients with negative diagnostic radioiodine scan and elevated serum Tg or positive TgAb under ETS were included. Correlation with clinicopathological features and recurrence, detectability of FDG PET/CT and cut-off value of serum Tg for recurrence in PTC patients with these circumstance were assessed. In addition, detectability of F-18 FDG PET/CT under ETS and suppression were compared. In Cox regression analysis, only serum Tg level was significantly associated with recurrence (P<0.001, HR  = 1.13; 95 % CI, 1.061–1.208). The cut-off level of Tg was 21.5 ng/mL (AUC, 0.919; P < 0.001) for discriminating the recurrence in the patients with positive PET/CT finding. The sensitivity, specificity, PPV, NPV, and accuracy of F-18 FDG PET/CT for detecting recurrence were 64 %, 94 %, 86 %, 81 %, and 83 %. In the analysis of F-18 FDG PET/CT under ETS, the sensitivity, specificity, PPV, NPV and accuracy was 64 %, 94 %, 88 %, 81 % and 83 %. Those under TSH suppression were 67 %, 92 %, 80 %, 85 % and 83 %. F-18 FDG PET/CT, although less sensitive, showed high specificity, PPV, NPV, and accuracy and therefore can be useful for the patients with negative diagnostic radioiodine scan and elevated serum Tg or positive TgAb. In addition, FDG PET/CT under ETS does not seem to have an additive role in detecting recurrence in these patients.

  11. Detection of Recurrent Cervical Cancer by Whole-body FDG PET Scans

    Institute of Scientific and Technical Information of China (English)

    Jiaxin Yang; Jinhui Wang; Zhaohui Zhu; Keng Shen; Bocheng Wang

    2008-01-01

    OBJECTIVE To evaluate the role of whole-body {18F} fluro-2-dexoxyglucose (FDG) positron emission tomography (PET) scans in the detection of recurrent cervical cancer.METHODS Between June, 2000 and January, 2006, 25 patients had undergone a PET scan at the Peking Union Medical College Hospital to evaluate possible recurrent cervical cancer. All the PET findings were reviewed and compared to available clinical data to classify each PET scan result as a true positive, true negative, false positive, or false negative.RESULTS A total of 38 PET scans were conducted on the 25patients whose median age was 46 years. The Stage distributions were IA (n = 1), IB (n = 11), IIA (n = 5), IIB (n = 4), IIIB (n = 2), WB (n= 1), and unknown Stage (n = 1). There were 22 cases of squamous cell carcinoma and 3 cases of adenocarcinoma resulting in 9 true positive PET scans, 27 true negatives, 2 false positives and no false negatives. The sensitivity of the FDG PET scans for detecting recurrent cervical cancer was 100%, specificity 93.1%, positive predictive value 81.8%, and negative predictive value 100%.CONCLUSION The whole body FDG PET scans are a sensitive and specific imaging modality for the detection of recurrent cervical cancer. However the cost of PET scans is too high at this time. A large prospective study will determine whether this modality should be used routinely and take the place of other imaging methods in the early detection of recurrent cervical carcinoma

  12. Clinical significance of bone scintigraphy and computerized tomography (CT scan) in the evaluation of renal osteodystrophy in haemodialysed and non-haemodialysed patients

    International Nuclear Information System (INIS)

    Yatsuboshi, Motohiko

    1978-01-01

    For the evaluation of renal osteodystophy in both haemodialysed and non-haemodialysed patients, bone scintigraphy and computerized tomography (CT) scan were performed. Twenty-six patients with chronic renal failure were objectives of the study. For the control study of CT scan, patients with brain tumor without renal disease were selected. Bone scan was performed approximately 3 hours after sup(99m) Tc-EHDP (ethane-1-hydroxy-1, 1-diphosphonate) administration. The numericals which were printed out from CT scanner were analyzed in the area of frontal bone. The number of positive group was 9 and that of negative was 17. Positive group in non-haemodialysed patients showed lower serum calcium level and creatinine clearance and higher serum levels of inorganic phosphate and BUN compared with those of negative group. Positive scan group showed longer duration of dialysis and higher serum levels of parathyroid hormone and alkaline phosphatase than those of negative group. Frequency of abnormal findings detected by bone scan was higher than that elicited by roentgenographic examination. CT number of positive scan group was lower than that of negative group or control group. CT number in patients with subperiosteal resorption of phalanx and abnormal findings of calvarium was lower than that of patients without such roentgenographic abnormalities. These findings indicate that bone scan is useful in detecting bone changes of secondary hyperparathyroidism in chronic renal failure. CT scan could also help to estimate the decrease of bone density of calvarium in chronic renal failure. (author)

  13. Rapid line scan MR angiography

    International Nuclear Information System (INIS)

    Frahm, J.; Merboldt, K.D.; Hanicke, W.; Bruhn, H.

    1987-01-01

    Direct MR angiography may be performed using line scan imaging techniques combined with presaturation of stationary spins. Thus, a single line scan echo yields a projection of vessels due to the signal from reflowing unsaturated spins. Reconstruction of an angiographic image is performed line by line at slightly incremented positions. In particular, line scan angiography is direct and fast without a sensitivity to artifacts even for high flow rates. Image resolution and field of view may be chosen without restrictions, and zoom images using enhanced gradients may be recorded without aliasing artifacts. The method is robust with respect to eddy currents and pulsatile flow. Line scan MR angiograms of phantoms, animals, and human volunteers have been recorded using 90 0 radio frequency pulses and gradient-recalled echoes

  14. Body indices and basic vital signs in Helicobacter pylori positive and negative persons

    International Nuclear Information System (INIS)

    Kopacova, Marcela; Bures, Jan; Koupil, Ilona; Rejchrt, Stanislav; Vorisek, Viktor; Seifert, Bohumil; Pozler, Oldrich; Zivny, Pavel; Douda, Tomas; Palicka, Vladimir; Holcik, Jan

    2007-01-01

    It has been hypothesized that Helicobacter pylori (Hp) infection may contribute to reduced stature, risk of hypertension or obesity. The aim was to evaluate body indices in Hp positive and negative persons. A total of 2436 subjects (4-100 years old) were tested for Hp status by 13 C-urea breath test. Data on height and weight were collected for 84%, and blood pressure for 80% of the study subjects. The prevalence of Hp infection was 41.6%. The odds ratio for a 10-year increase in age was 1.21 (95% CI 1.17-1.25, p-value <0.001). Statistically significant negative association of Hp positivity with body height was most pronounced in the younger age groups, while a positive association of Hp positivity with body mass index was only seen in those aged 15+ years. There was a negative effect of Hp positivity on systolic and diastolic blood pressure in subjects below 25 and a relatively strong positive effect on blood pressure in subjects over 65 years. Residual confounding by social characteristics as a possible explanation for the associations of Hp positivity with height and blood pressure cannot be excluded. Unmeasured factors related to social and family environment may cause the apparent association between Hp positivity and children's growth and blood pressure

  15. Evaluation of positional plagiocephaly: Conventional anthropometric measurement versus laser scanning method.

    Science.gov (United States)

    Nahles, Susanne; Klein, Martin; Yacoub, Anke; Neyer, Julia

    2018-01-01

    The incidence of plagiocephaly has increased in the 25 years since the "Back to Sleep" campaign in 1991 to prevent sudden infant death. Plagiocephaly is not considered to be a pathological condition. It is more of an esthetic impairment and could have potentially negative psychological or psychosocial consequences; therefore, treatment is recommended. The aim of this study is to compare conventional anthropometry and laser scanning - two different measurement methods - as diagnostic instruments for plagiocephaly. The present study also tests the measurement time of both methods and whether one method is easier on the patient than the other. A total of 44 children (21 girls, 23 boys) with a mean age of 8.8 months were involved in the present study. Of all patients, the following parameters were routinely evaluated using a standard protocol with the conventional anthropometric method and the scan method: head circumference, head length, head width, head diagonals, and distances ex-t. Furthermore, the time required to obtain measurements and the behavior of the children during measurement were documented. For statistical analysis, a t-test and a Wilcoxon test were used to analyze differences between the two methods. The results for head circumference showed a mean of 441.5 mm for the anthropometric measurements and 441.6 mm for the scan method, with no significant difference between the two methods. A significant difference was found regarding the head width, head length, diagonals, and distance ex-t. The measurement process using the scan method needed a mean of 579.6 s in contrast to the manual anthropometric method, which required a mean time of 180.5 s. In comparison with the conventional anthropometric method, measurements made with a 3D laser scanner yield inconsistent results. Moreover, the current state of technology of 3D cephalometry has no advantages compared with the conventional anthropometric method. Disadvantages worth mentioning appear to be the

  16. Clinical indications to the use of (99m)Tc-EDDA/HYNIC-TOC to detect somatostatin receptor-positive neuroendocrine tumors.

    Science.gov (United States)

    Parisella, M G; Chianelli, M; D'Alessandria, C; Todino, V; Mikolajczak, R; Papini, E; Dierckx, R A; Scopinaro, F; Signore, A

    2012-02-01

    The aim of this study was to define, retrospectively, the utility to perform (99m)Tc-EDDA/HYNIC-Tyr3-octreotide ((99m)Tc-EDDA/HYNIC-TOC) scan in patients with NET. We studied 50 consecutive patients affected by different types of NET and divided in two groups. Group 1: 34 patients with known lesions in which (99m)Tc-EDDA/HYNIC-TOC was performed for staging, characterisation or to choose the appropriate treatment. Group 2: 16 patients suspected of having NET or in follow up after surgery. Patients were injected with 370 MBq of (99m)Tc-EDDA/HYNIC-Tyr3-octreotide and whole-body and SPET images acquired 2-3 hours after injection. Overall, 29 patients (58%) had a positive scan, with a sensitivity, specificity and accuracy of 70.3%, 76.9% and 72%, respectively (78.1%, 50% and 76.5%, in group 1 and 20%, 81.2%, 62.5% in group 2). In patients from group 1 (99m)Tc-HYNIC-TOC scintigraphy showed a concordance of 68% with another imaging procedure and in 9 patients revealed a greater number of lesions. In the second group, false negative results were especially found in patients with medullary thyroid cancer with negative radiological findings and elevated calcitonin. In conclusion, (99m)Tc-EDDA/HYNIC-TOC is highly indicated for in vivo histological characterization of known NET lesions, previously identified by other imaging modalities or biopsy, to plan appropriate therapy especially for patients with inoperable disease. In patients with only biochemical suspicion of NET and in those with negative markers, this scintigraphy does not significantly modify the clinical management.

  17. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... the gland following medication use, surgery, radiotherapy or chemotherapy top of page How should I prepare? You ... but is often performed on hospitalized patients as well. Thyroid Scan You will be positioned on an ...

  18. Different nutritional-state indicators of HIV-positive individuals undergoing antiretroviral therapy

    Directory of Open Access Journals (Sweden)

    J. Geraix

    2008-01-01

    Full Text Available This study aimed at learning about the nutritional profile of HIV-positive individuals undergoing antiretroviral therapy and at comparing the performance of nutritional-state indicators. A transversal study was performed on 94 patients attending the Tropical Diseases Outpatient Hospital of Botucatu Medical School (FMB - UNESP. The body mass index (BMI and the classification by Papini-Berto (PB were used to evaluate nutritional state, aiming at detecting malnutrition and obesity. The waist-to-hips ratio (W/HR and waist circumference (WC were adopted for identification of abdominal obesity and lipodystrophy. According to BMI, most of the individuals were eutrophic, followed by 30.9% overweight and 6.4% malnourished. By using the PB classification, the frequency of malnourished increased (22.3%. The analysis of the PB classification in relation to BMI indicated that the former presented high sensitivity and good specificity for malnutrition diagnosis, namely 100% and 83%, respectively. The prevalence of abdominal obesity was 7.44% according to WC, and a higher prevalence (38.3% was observed when taking W/HR into account. There was significant positive association between nutritional diagnosis according to PB and T CD4+ lymphocyte. The results support the use of PB classification for malnutrition detection as well as that of BMI and W/HR for overweight and fat redistribution.

  19. Developments in Scanning Hall Probe Microscopy

    Science.gov (United States)

    Chouinard, Taras; Chu, Ricky; David, Nigel; Broun, David

    2009-05-01

    Low temperature scanning Hall probe microscopy is a sensitive means of imaging magnetic structures with high spatial resolution and magnetic flux sensitivity approaching that of a Superconducting Quantum Interference Device. We have developed a scanning Hall probe microscope with novel features, including highly reliable coarse positioning, in situ optimization of sensor-sample alignment and capacitive transducers for linear, long range positioning measurement. This has been motivated by the need to reposition accurately above fabricated nanostructures such as small superconducting rings. Details of the design and performance will be presented as well as recent progress towards time-resolved measurements with sub nanosecond resolution.

  20. The diagnostic value of monoclonal antibody scan (leucoscan) compared with 99mTc MDP bone scan and Ga 67 in diagnosing bone and joint infection

    International Nuclear Information System (INIS)

    Koukouraki, S.I.; Velidaki, A.; Prassopoulos, V.; Karkavitsas, N.; Vavouranakis, H.; Hatjipavlou, A.

    2002-01-01

    Full text: Nowadays different radiopharmaceuticals have been developed as 99mTc MDP, 67Ga citrate, 111In oxine- and 99mTc HMPAO labeled leucocytes for the accurate localization of bone/joint infection, but all of them have limitations that encouraged the search of new agents characterized from high and early uptake in infectious/inflammatory tissues, low toxicity and no accumulation in non inflamed tissues. The purpose of this study is to compare the diagnostic value of a 99mTc labeled antigranulocyte Fab' fragment (Leucoscan) with 99mTc MDP bone scan and 67 Ga. The monoclonal antibody, Leucoscan, is an IgG murine Fab' fragment directed against a NCA-90 epitope located on the surface of granulocytes. 45 patients with suspected bone and joint infection (18 total hip prosthesis, 4 knee prosthesis, 8 vertebral infection and 15 long bones) were included in this study. All patients underwent conventional Rx, bone scan, 67Ga scan and Leucoscan. Three phase 99mTc MDP bone scan and 67Ga scan were performed using standard procedures. For Leucoscan the antibody was labeled with 25 mCi of 99mTc and was infected intravenously over 30 seconds. Ten minutes planar images were taken 1 h and 2 hrs p.i using a GE Millennium γ camera provided with a LEGP collimator. Images were evaluated as score 1 (no abnormal uptake), score 2 (probably positive), score 3 (definitely infected) according the intensity of abnormally increased uptake. Results were compared with 99mTc MDP bone scan and 67Ga scans. The final diagnosis was given by the surgical verification with histopathology or culture. All 45 patients had pathologic proof of presence/absence of bone and joint infection. 36/45 were positive for bone or joint infection and 9/45 were negative.30/36 patients with surgically proven bone and joint infection had true positive Leucoscan, 26/36 had true positive MDP bone scan and 20/36 true positive 67Ga scan. Nine out of 9 patients with proven absence of inflammation had true negative

  1. Role of delayed indium-111 labeled leukocyte scan in the management of Crohn's disease

    International Nuclear Information System (INIS)

    Slaton, G.D.; Navab, F.; Boyd, C.M.; Diner, W.C.; Texter, E.C. Jr.

    1985-01-01

    Comparison of nine patients with Crohn's disease who had a positive delayed (24 hr) 111 indium leukocyte scan and 10 patients with negative scan showed no significant difference between the two groups for the Crohn's disease activity index, sedimentation rate, survival, complications, number of days in hospital, outpatient visits, or readmissions. Despite the apparent lack of statistical significance in Crohn's disease activity index, the scan was positive in nine of 16 patients with a Crohn's disease activity index more than 150, and none of three patients with Crohn's disease activity index less than 150. In the patients studied, there were no false-positive leukocyte scans. In nine of 10 patients with ileocolonic disease, scanning results correctly predicted the proper management. Six patients with positive scan and enteroclysis responded to medical treatment. Four patients had positive enteroclysis and negative scan; of these, three had radiographic features of chronic ileal stricture which was confirmed at operation. The results suggest that a negative delayed indium-111 leukocyte scan may be useful in diagnosis of chronic fibrotic ileal stricture

  2. Optical vortex scanning inside the Gaussian beam

    International Nuclear Information System (INIS)

    Masajada, J; Leniec, M; Augustyniak, I

    2011-01-01

    We discussed a new scanning method for optical vortex-based scanning microscopy. The optical vortex is introduced into the incident Gaussian beam by a vortex lens. Then the beam with the optical vortex is focused by an objective and illuminates the sample. By changing the position of the vortex lens we can shift the optical vortex position at the sample plane. By adjusting system parameters we can get 30 times smaller shift at the sample plane compared to the vortex lens shift. Moreover, if the range of vortex shifts is smaller than 3% of the beam radius in the sample plane the amplitude and phase distribution around the phase dislocation remains practically unchanged. Thus we can scan the sample topography precisely with an optical vortex

  3. Comparison of thallium-201 scan and Tc-99m sestamibi scan in the differential diagnosis of breast mass

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Ihn Ho; Won, Kyu Jang; Lee, Hyung Woo; Lee, Soon Jung [College of Medicine, Yonsei Univ., Seoul (Korea, Republic of)

    1999-02-01

    We performed this study to compare Tl-201 and Tc-99m MIBI scans for the differentiation of malignant from benign breast mass. Thirty-eight female patients underwent Tl-201 breast scan and thirty-two of them also underwent Tc-99m MIBI scan of the breast. After intravenous injection of 74-111 MBq of Tl-201, early (10 minutes) and delayed (3 hours) images were obtained. Then, 555-740 MBq of Tc-99m MIBI was injected and images after 30 minutes were obtained. We compared Tl-201 and Tc-99m MIBI scans with pathologic results. Twenty-three patients were confirmed to have infiltrating duct carcinoma and fifteen patients to have benign breast mass by excisonal biopsy. The sensitivity of early and delayed Tl-201 scan and Tc-99m MIBI scan in the detection of malignant breast lesion were 100% (23/23), 82% (18/22), and 90% (18/20), respectively. The sensitivity of early Tl-201 scan was significantly higher than that of delayed Tl-201 scan, (p<0.05). The specificity of early and delayed Tl-201 scan and Tc-99m MIBI scan were 73% (11/15), 73% (11/15) and 83% (10/12), respectively (p: not significant). Three patients out of nine with fibroadenoma and one patient with atypical duct hyperplasia were false positive in both early and delayed Tl-201 scans. The size of fibroadenoma with false positive in early and delayed Tl-201 scan (4 cases) was larger than that of 11 fibroadenoma with true negative scan (p<0.01). Metastatic axillary lymph node involvement was present in fifteen patients. The sensitivity to detect metastatic nodes was 38% (5/13) for early Tl-201 images, 15% (2/13) for delayed Tl-201 images, 58% (7/12) for Tc-99m MIBI planar images and 67% (4/6) for Tc-99m MIBI SPECT. The sensitivity of Tc-99m MIBI planar or SPECT was significantly higher than that of delayed Tl-201 images (p<0.05). Early Tl-201 and Tc-99m MIBI scan are useful noninvasive methods to differentiate malignant from benign mass of breast. Tc-99m MIBI scan was sensitive in detecting axillary lymph node

  4. Evaluation of muscular lesions in connective tissue diseases: thallium 201 muscular scans

    International Nuclear Information System (INIS)

    Guillet, G.; Guillet, J.; Sanciaume, C.; Maleville, J.; Geniaux, M.; Morin, P.

    1988-01-01

    We performed thallium 201 muscle scans to assess muscular involvement in 40 patients with different connective tissue diseases (7 with dermatomyositis, 7 with systemic lupus erythematosus, 12 with progressive systemic scleroderma, 2 with calcinosis, Raynaud's phenomenon, esophageal involvement, sclerodactyly, and telangiectasia (CREST) syndrome, 3 with monomelic scleroderma, 6 with morphea, and 3 with Raynaud's disease). Only 12 of these patients complained of fatigability and/or myalgia. Electromyography was performed and serum levels of muscle enzymes were measured in all patients. Comparison of thallium 201 exercise recording with the other tests revealed that scan sensitivity is greater than electromyographic and serum muscle enzymes levels. Thallium 201 scans showed abnormal findings in 32 patients and revealed subclinical lesions in 18 patients, while electromyography findings were abnormal in 25 of these 32 patients. Serum enzyme levels were raised in only 8 patients. Thallium 201 scanning proved to be a useful guide for modifying therapy when laboratory data were conflicting. It was useful to evaluate treatment efficacy. Because our data indicate a 100% positive predictive value, we believe that thallium 201 scanning should be advised for severe systemic connective tissue diseases with discordant test results

  5. Evaluation of muscular lesions in connective tissue diseases: thallium 201 muscular scans

    Energy Technology Data Exchange (ETDEWEB)

    Guillet, G.; Guillet, J.; Sanciaume, C.; Maleville, J.; Geniaux, M.; Morin, P.

    1988-04-01

    We performed thallium 201 muscle scans to assess muscular involvement in 40 patients with different connective tissue diseases (7 with dermatomyositis, 7 with systemic lupus erythematosus, 12 with progressive systemic scleroderma, 2 with calcinosis, Raynaud's phenomenon, esophageal involvement, sclerodactyly, and telangiectasia (CREST) syndrome, 3 with monomelic scleroderma, 6 with morphea, and 3 with Raynaud's disease). Only 12 of these patients complained of fatigability and/or myalgia. Electromyography was performed and serum levels of muscle enzymes were measured in all patients. Comparison of thallium 201 exercise recording with the other tests revealed that scan sensitivity is greater than electromyographic and serum muscle enzymes levels. Thallium 201 scans showed abnormal findings in 32 patients and revealed subclinical lesions in 18 patients, while electromyography findings were abnormal in 25 of these 32 patients. Serum enzyme levels were raised in only 8 patients. Thallium 201 scanning proved to be a useful guide for modifying therapy when laboratory data were conflicting. It was useful to evaluate treatment efficacy. Because our data indicate a 100% positive predictive value, we believe that thallium 201 scanning should be advised for severe systemic connective tissue diseases with discordant test results.

  6. Metrological large range scanning probe microscope

    International Nuclear Information System (INIS)

    Dai Gaoliang; Pohlenz, Frank; Danzebrink, Hans-Ulrich; Xu Min; Hasche, Klaus; Wilkening, Guenter

    2004-01-01

    We describe a metrological large range scanning probe microscope (LR-SPM) with an Abbe error free design and direct interferometric position measurement capability, aimed at versatile traceable topographic measurements that require nanometer accuracy. A dual-stage positioning system was designed to achieve both a large measurement range and a high measurement speed. This dual-stage system consists of a commercially available stage, referred to as nanomeasuring machine (NMM), with a motion range of 25 mmx25 mmx5 mm along x, y, and z axes, and a compact z-axis piezoelectric positioning stage (compact z stage) with an extension range of 2 μm. The metrological LR-SPM described here senses the surface using a stationary fixed scanning force microscope (SFM) head working in contact mode. During operation, lateral scanning of the sample is performed solely by the NMM. Whereas the z motion, controlled by the SFM signal, is carried out by a combination of the NMM and the compact z stage. In this case the compact z stage, with its high mechanical resonance frequency (greater than 20 kHz), is responsible for the rapid motion while the NMM simultaneously makes slower movements over a larger motion range. To reduce the Abbe offset to a minimum the SFM tip is located at the intersection of three interferometer measurement beams orientated in x, y, and z directions. To improve real time performance two high-end digital signal processing (DSP) systems are used for NMM positioning and SFM servocontrol. Comprehensive DSP firmware and Windows XP-based software are implemented, providing a flexible and user-friendly interface. The instrument is able to perform large area imaging or profile scanning directly without stitching small scanned images. Several measurements on different samples such as flatness standards, nanostep height standards, roughness standards as well as sharp nanoedge samples and 1D gratings demonstrate the outstanding metrological capabilities of the instrument

  7. Magnetically scanned proton therapy beams: rationales and techniques

    International Nuclear Information System (INIS)

    Jones, D.T.L.; Schreuder, A.N.

    2000-01-01

    Perhaps the most important advantages of beam scanning systems for proton therapy in comparison with conventional passive beam spreading systems are: (1) Intensity modulation and inverse planning are possible. (2) There is negligible reduction in the range of the beam. (3) Integral dose is reduced as dose conformation to the proximal edge of the lesion is possible. (4) In principle no field-specific modifying devices are required. (5) There is less activation of the surroundings. (6) Scanning systems axe almost infinitely flexible. The main disadvantages include: (1) Scanning systems are more complicated and therefore potentially less reliable and more dangerous. (2) The development of such systems is more demanding in terms of cost, time and manpower. (3) More stable beams are required. (4) Dose and beam position monitoring are more difficult. (5) The problems associated with patient and organ movement axe more severe. There are several techniques which can be used for scanning. For lateral beam spreading, circular scanning (wobbling) or linear scanning can be done. In the latter case the beam can be scanned continuously or in a discrete fashion (spot scanning). Another possibility is to undertake the fastest scan in one dimension (strip scanning) and translate the patient or the scanning magnet in the other dimension. Depth variation is achieved by interposing degraders in the beam (cyclotrons) or by changing the beam energy (synchrotrons). The aim of beam scanning is to deliver a predetermined dose at any point in the body. Special safety precautions must be taken because of the high instantaneous dose rates. The beam position and the dose delivered at each point must be accurately and redundantly determined. (author)

  8. Colon distension and scan protocol for CT-colonography: An overview

    Energy Technology Data Exchange (ETDEWEB)

    Boellaard, Thierry N., E-mail: t.n.boellaard@amc.uva.nl [Department of Radiology, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands); Haan, Margriet C. de, E-mail: m.c.dehaan@amc.uva.nl [Department of Radiology, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands); Venema, Henk W., E-mail: h.w.venema@amc.uva.nl [Department of Radiology, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands); Department of Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands); Stoker, Jaap, E-mail: j.stoker@amc.uva.nl [Department of Radiology, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands)

    2013-08-15

    This article reviews two important aspects of CT-colonography, namely colonic distension and scan parameters. Adequate distension should be obtained to visualize the complete colonic lumen and optimal scan parameters should be used to prevent unnecessary radiation burden. For optimal distension, automatic carbon dioxide insufflation should be performed, preferably via a thin, flexible catheter. Hyoscine butylbromide is – when available – the preferred spasmolytic agent because of the positive effect on insufflation and pain/burden and its low costs. Scans in two positions are required for adequate distension and high polyp sensitivity and decubitus position may be used as an alternative for patients unable to lie in prone position. The great intrinsic contrast between air or tagging and polyps allows the use of low radiation dose. Low-dose protocol without intravenous contrast should be used when extracolonic findings are deemed unimportant. In patients suspected for colorectal cancer, normal abdominal CT scan protocols and intravenous contrast should be used in supine position for the evaluation of extracolonic findings. Dose reduction can be obtained by lowering the tube current and/or voltage. Tube current modulation reduces the radiation dose (except in obese patients), and should be used when available. Iterative reconstructions is a promising dose reducing tool and dual-energy CT is currently evaluated for its applications in CT-colonography. This review also provides our institution's insufflation procedure and scan parameters.

  9. The value of indicated computed tomography scan of the chest and abdomen in addition to the conventional radiologic work-up for blunt trauma patients.

    NARCIS (Netherlands)

    Deunk, J.; Dekker, H.M.; Brink, M.; Vugt, R. van; Edwards, M.J.R.; Vugt, A.B. van

    2007-01-01

    BACKGROUND: Multidetector computed tomography (CT) is more sensitive and specific in detecting traumatic injuries than conventional radiology is. However, still little is known about the diagnostic value and the therapeutic impact of indicated thoraco-abdominal CT scan when it is performed in

  10. Radioisotope spleen scan in patients with splenic injury

    International Nuclear Information System (INIS)

    Mishalany, H.G.; Miller, J.H.; Woolley, M.M.

    1982-01-01

    The technetium /sup 99m/Tc sulfur colloid liver-spleen scan is a valuable aid in diagnosis and treatment of patients with splenic injury. After reviewing the charts of 47 patients who were ill as a result of splenic trauma, we came to the following conclusions: (1) the scan identified the injury, accurately mapped its extent, and indicated the presence or absence of associated liver injuries; (2) the scans were useful in following the extent and rate of healing of the splenic injury; (3) the scan is an indirect measurement of of return of splenic fuction; (4) the procedure can be performed in a reasonable time frame with no serious morbidity; and (5) the indications, contraindications, and timing of scans are now reasonably well established

  11. Radioisotope spleen scan in patients with splenic injury

    Energy Technology Data Exchange (ETDEWEB)

    Mishalany, H.G.; Miller, J.H.; Woolley, M.M.

    1982-09-01

    The technetium /sup 99m/Tc sulfur colloid liver-spleen scan is a valuable aid in diagnosis and treatment of patients with splenic injury. After reviewing the charts of 47 patients who were ill as a result of splenic trauma, we came to the following conclusions: (1) the scan identified the injury, accurately mapped its extent, and indicated the presence or absence of associated liver injuries; (2) the scans were useful in following the extent and rate of healing of the splenic injury; (3) the scan is an indirect measurement of of return of splenic fuction; (4) the procedure can be performed in a reasonable time frame with no serious morbidity; and (5) the indications, contraindications, and timing of scans are now reasonably well established.

  12. False-positive I-131 scan by contaminated muffler in a patient with thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Han Kyung; Kim, Min Woo; Jeong, Hwan Jeong; Sohn, Myung Hee [Chonbuk National University Hospital, Chonju (Korea, Republic of)

    2006-02-15

    A 39-year-old female patient who had undergone a total thyroidectomy for a papillary thyroid carcinoma underwent a whole body scan with I-131. The I-131 scan was performed 72 hours after administering 185 MBq (5 mGi) of an I-131 solution. The anterior image of head, neck, and upper chest showed multiple areas of increased uptake in the mediastinal area considering of functional metastasis. However, radioactivity was not evident in the image taken after removing her clothes and muffler. The image obtained after placing the muffler on the pallet showed that the radioactivity was still present. It is well known that artifacts on an I-131 scan can be produced by styling hair sputum, drooling during sleep, chewing gum, and paper or a cloth handkerchief that is contaminated with the radioactive iodine from either perspiration or saliva. This activity might be mistaken for a functional metastasis. Therefore, it is essential that an image be obtained after removing the patient's clothes. In this study, artifacts due to a contaminated muffler on the I-131 scan were found. These mimicked a functional metastasis of the mediastinal area in a patient with a papillary thyroid carcinoma.

  13. Reduction of motion artifacts for PET imaging by respiratory correlated dynamic scanning

    International Nuclear Information System (INIS)

    Chuang, K.-S.; Chen, T.-J.; Chang, C.-C.; Wu, J.; Chen, S.; Wu, L.-C.; Liu, R.-S.

    2006-01-01

    Organ motion caused by respiration is a major challenge in positron emission tomography (PET) imaging. This work proposes a technique to reduce smearing in PET imaging caused by respiratory motion. Dynamic scanning at 1 frame/s is used. A point source, used as a marker, is attached to the object's abdomen during the scan. The source position in the projection view moves with respiratory motion and can be used to represent the respiratory phase within the time interval in which each frame data are acquired. One hundred and twenty frames are obtained for each study. The range of the positions of the marker is divided into four groups, representing different respiratory phases. The frames in which the organ positions (phases) are the same summed to produce a static sub-sinogram. Each sub-sinogram then undergoes regular image reconstruction to yield a motion-free image. The technique is applied to one volunteer under both free and coached breathing conditions. A parameter called the volume reduction factor is adopted to evaluate the effectiveness of this motion-reduction technique. The preliminary results indicate that the proposed technique effectively reduces motion artifacts in the image. Coached breathing yields better results than free breathing condition. The advantages of this method are that (1) the scanning time remains the same; (2) free breathing is allowed during the acquisition of the image; and (3) no user intervention is required

  14. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... process that regulates the rate at which the body converts food to energy. top of page What are some common uses of the procedure? The thyroid scan is used to determine the size, shape and position of the thyroid gland. The ...

  15. A map of recent positive selection in the human genome.

    Directory of Open Access Journals (Sweden)

    Benjamin F Voight

    2006-03-01

    Full Text Available The identification of signals of very recent positive selection provides information about the adaptation of modern humans to local conditions. We report here on a genome-wide scan for signals of very recent positive selection in favor of variants that have not yet reached fixation. We describe a new analytical method for scanning single nucleotide polymorphism (SNP data for signals of recent selection, and apply this to data from the International HapMap Project. In all three continental groups we find widespread signals of recent positive selection. Most signals are region-specific, though a significant excess are shared across groups. Contrary to some earlier low resolution studies that suggested a paucity of recent selection in sub-Saharan Africans, we find that by some measures our strongest signals of selection are from the Yoruba population. Finally, since these signals indicate the existence of genetic variants that have substantially different fitnesses, they must indicate loci that are the source of significant phenotypic variation. Though the relevant phenotypes are generally not known, such loci should be of particular interest in mapping studies of complex traits. For this purpose we have developed a set of SNPs that can be used to tag the strongest approximately 250 signals of recent selection in each population.

  16. Scan analysis in myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Ell, P J [Landesunfallkrankenhaus, Feldkirch (Austria). Inst. fuer Strahlenmedizin

    1976-08-01

    Myocardial scans with sup(99m)Tc-labelled phosphates are reported to be useful in the diagnosis of acute myocardial infarction. A retrospective survey of 205 patients referred for sup(99m)Tc-phophate bone scanning and with no evidence of recent heart disease revealed an occurrence of 10% of false positive images, that is to say, uptake of phosphate in non-infarcted mayocardium. These striking findings stress the need for critical assessment of the usefulness of this diagnostic technique.

  17. [Molecular beacon based PNA-FISH method combined with fluorescence scanning for rapid detection of Listeria monocytogenes].

    Science.gov (United States)

    Wu, Shan; Zhang, Xiaofeng; Shuai, Jiangbing; Li, Ke; Yu, Huizhen; Jin, Chenchen

    2016-07-04

    To simplify the PNA-FISH (Peptide nucleic acid-fluorescence in situ hybridization) test, molecular beacon based PNA probe combined with fluorescence scanning detection technology was applied to replace the original microscope observation to detect Listeria monocytogenes The 5′ end and 3′ end of the L. monocytogenes specific PNA probes were labeled with the fluorescent group and the quenching group respectively, to form a molecular beacon based PNA probe. When PNA probe used for fluorescence scanning and N1 treatment as the control, the false positive rate was 11.4%, and the false negative rate was 0; when N2 treatment as the control, the false positive rate decreased to 4.3%, but the false negative rate rose to 18.6%. When beacon based PNA probe used for fluorescence scanning, taken N1 treatment as blank control, the false positive rate was 8.6%, and the false negative rate was 1.4%; taken N2 treatment as blank control, the false positive rate was 5.7%, and the false negative rate was 1.4%. Compared with PNA probe, molecular beacon based PNA probe can effectively reduce false positives and false negatives. The success rates of hybridization of the two PNA probes were 83.3% and 95.2% respectively; and the rates of the two beacon based PNA probes were 91.7% and 90.5% respectively, which indicated that labeling the both ends of the PNA probe dose not decrease the hybridization rate with the target bacteria. The combination of liquid phase PNA-FISH and fluorescence scanning method, can significantly improve the detection efficiency.

  18. Complementary role of CT and In-111 leukocyte scans in the diagnosis of infected hematoma and thrombosis

    International Nuclear Information System (INIS)

    Kim, E.E.; Pjura, G.A.; Floyd, W.; Raval, B.; Sandler, C.; Gobuty, A.H.

    1984-01-01

    Patients with traumatic hematomas or those with indwelling catheters who subsequently develop fever and sepsis without clinical localizing signs to indicate an inflammatory focus can present a diagnostic dilemma. Early diagnosis of an infected hematoma or thrombus is important to optimal management. CT can provide, exquisite delineation of anatomy identifying and localizing a post-traumatic fluid collection but cannot reliably distinguish hematoma from abscess in all cases. A thrombus at a catheter tip may be too small to be resolved; when identified, the question of infection again remains. In-111 leukocyte scanning provides a method for identifying or ruling out infection in these situations. The authors performed In-111 leukocyte scans on 15 patients with indwelling catheters. Five of these patients were febrile with positive blood cultures. In-111 leukocyte scans showed positive findings in 8 patients: 5 showed surgically confirmed infected hematomas in the abdomen (3 in the pelvis, 1 in a kidney, 1 in the splenic bed), and 3 showed infected thrombosis in catheter tips. The authors conclude that CT scanning and In-111 leukocyte scanning play complementary roles in the evaluation of traumatic hematomas and thrombosis, the former providing precise anatomic delineation and the latter providing evidence of inflammation

  19. Role of mediastinal and multi-organ CT scans in staging presumable surgical candidates with non-small-cell lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Osada, Hiroaki; Nakajima, Yasuo; Taira, Yasuhiko; Yokote, Kumio; Noguchi, Teruhiko

    1987-09-01

    In order to evaluate the role of CT scan and bone scan in staging patients with non-small-cell lung cancer presumably indicated for surgery, 70 consecutive patients who underwent thoracotomy were reviewed. Most of them received mediastinal and multi-organ (brain, liver and adrenal) CT scans and a bone scan. In the most recent 40 of the 70 patients, CT findings of the mediastinal lymph nodes were compared to the pathology following complete sampling. The overall accuracy of the mediastinal CT was 60.0 per cent (12 true positive and 12 true negative), but the negative predictable value was 12/(12 + 3) or 80.0 per cent, whereas 3 were false negatives though they showed an acceptable postoperative course. Sixteen out of 21 patients with one, or at the most, three enlarged nodes detected on CT also did well postoperatively and retrospectively, were considered not to have required mediastinoscopy. A group of patients showing no, or at the most, three enlarged mediastinal lymph nodes on CT may be considered as candidates for surgery even without mediastinoscopy. Multi-organ survey by means of CT was believed cost-ineffective and omittable. Bone scan however, retrospectively detected three true positives among 20 patients with a positive uptake, so that it cannot be omitted out of hand, though further examination of this point is required.

  20. National quality indicators and policies from 15 countries leading in adult end-of-life care: a systematic environmental scan.

    Science.gov (United States)

    Virdun, Claudia; Luckett, Tim; Lorenz, Karl A; Phillips, Jane

    2018-06-01

    The importance of measuring the quality of end-of-life care provision is undisputed, but determining how best to achieve this is yet to be confirmed. This study sought to identify and describe national end-of-life care quality indicators and supporting policies used by countries leading in their end-of-life care provision. A systematic environmental scan that included a web search to identify relevant national policies and indicators; hand searching for additional materials; information from experts listed for the top 10 (n=15) countries ranked in the 'quality of care' category of the 2015 Quality of Death Index study; and snowballing from Index experts. Ten countries (66%) have national policy support for end-of-life care measurement, five have national indicator sets, with two indicator sets suitable for all service providers. No countries mandate indicator use, and there is limited evidence of consumer engagement in development of indicators. Two thirds of the 128 identified indicators are outcomes measures (62%), and 38% are process measures. Most indicators pertain to symptom management (38%), social care (32%) or care delivery (27%). Measurement of end-of-life care quality varies globally and rarely covers all care domains or service providers. There is a need to reduce duplication of indicator development, involve consumers, consider all care providers and ensure measurable and relevant indicators to improve end-of-life care experiences for patients and families. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  1. Nuclear scanning in necrotizing progressive ''malignant'' external otitis

    International Nuclear Information System (INIS)

    Parisier, S.C.; Lucente, F.E.; Som, P.M.; Hirschman, S.Z.; Arnold, L.M.; Roffman, J.D.

    1982-01-01

    The usefulness of radionuclear scanning in the treatment of 18 patients with necrotizing progressive ''malignant'' external otitis is discussed. A Tc 99-m bone scan, a valuable test since results are positive in early cases of osteomyelitis of the temporal bone and base of skull, showed increased uptake in all 18 patients. In 6 patients, Ga-67 citrate scans were obtained at the start of therapy and at 5-6 week intervals thereafter. The serial gallium scans were useful in evaluating the effectiveness of therapy since the uptake decrease with control of infection

  2. Automatic calibration method of voxel size for cone-beam 3D-CT scanning system

    International Nuclear Information System (INIS)

    Yang Min; Wang Xiaolong; Wei Dongbo; Liu Yipeng; Meng Fanyong; Li Xingdong; Liu Wenli

    2014-01-01

    For a cone-beam three-dimensional computed tomography (3D-CT) scanning system, voxel size is an important indicator to guarantee the accuracy of data analysis and feature measurement based on 3D-CT images. Meanwhile, the voxel size changes with the movement of the rotary stage along X-ray direction. In order to realize the automatic calibration of the voxel size, a new and easily-implemented method is proposed. According to this method, several projections of a spherical phantom are captured at different imaging positions and the corresponding voxel size values are calculated by non-linear least-square fitting. Through these interpolation values, a linear equation is obtained that reflects the relationship between the voxel size and the rotary stage translation distance from its nominal zero position. Finally, the linear equation is imported into the calibration module of the 3D-CT scanning system. When the rotary stage is moving along X-ray direction, the accurate value of the voxel size is dynamically exported. The experimental results prove that this method meets the requirements of the actual CT scanning system, and has virtues of easy implementation and high accuracy. (authors)

  3. False Positive Uptake in Bilateral Gynecomastia on 68Ga-PSMA PET/CT Scan.

    Science.gov (United States)

    Sasikumar, Arun; Joy, Ajith; Nair, Bindu P; Pillai, M R A; Madhavan, Jayaprakash

    2017-09-01

    A 66-year-old man on hormonal therapy with prostate cancer was referred for Ga-PSMA PET/CT scan for biochemical recurrence. Ga-PSMA PET/CT scan detected moderate heterogeneous tracer concentration in bilateral breast parenchyma, in addition to the abnormal tracer concentration in enlarged prostate gland, right external iliac lymph node, and sclerotic lesion in L4 vertebra. On clinical examination, he was found to have bilateral gynecomastia. Abnormal concentration of Ga-PSMA in breast cancer is now well known, and in this context, it is important to know that tracer localization can occur in gynecomastia as well, as evidenced in this case.

  4. Qualitative evaluation of coronary flow during anesthetic induction using thallium-201 perfusion scans

    Energy Technology Data Exchange (ETDEWEB)

    Kleinman, B.; Henkin, R.E.; Glisson, S.N.; el-Etr, A.A.; Bakhos, M.; Sullivan, H.J.; Montoya, A.; Pifarre, R.

    1986-02-01

    Qualitative distribution of coronary flow using thallium-201 perfusion scans immediately postintubation was studied in 22 patients scheduled for elective coronary artery bypass surgery. Ten patients received a thiopental (4 mg/kg) and halothane induction. Twelve patients received a fentanyl (100 micrograms/kg) induction. Baseline thallium-201 perfusion scans were performed 24 h prior to surgery. These scans were compared with the scans performed postintubation. A thallium-positive scan was accepted as evidence of relative hypoperfusion. Baseline hemodynamic and ECG data were obtained prior to induction of anesthesia. These data were compared with the data obtained postintubation. Ten patients developed postintubation thallium-perfusion scan defects (thallium-positive scan), even though there was no statistical difference between their baseline hemodynamics and hemodynamics at the time of intubation. There was no difference in the incidence of thallium-positive scans between those patients anesthetized by fentanyl and those patients anesthetized with thiopental-halothane. The authors conclude that relative hypoperfusion, and possibly ischemia, occurred in 45% of patients studied, despite stable hemodynamics, and that the incidence of these events was the same with two different anesthetic techniques.

  5. Qualitative evaluation of coronary flow during anesthetic induction using thallium-201 perfusion scans

    International Nuclear Information System (INIS)

    Kleinman, B.; Henkin, R.E.; Glisson, S.N.; el-Etr, A.A.; Bakhos, M.; Sullivan, H.J.; Montoya, A.; Pifarre, R.

    1986-01-01

    Qualitative distribution of coronary flow using thallium-201 perfusion scans immediately postintubation was studied in 22 patients scheduled for elective coronary artery bypass surgery. Ten patients received a thiopental (4 mg/kg) and halothane induction. Twelve patients received a fentanyl (100 micrograms/kg) induction. Baseline thallium-201 perfusion scans were performed 24 h prior to surgery. These scans were compared with the scans performed postintubation. A thallium-positive scan was accepted as evidence of relative hypoperfusion. Baseline hemodynamic and ECG data were obtained prior to induction of anesthesia. These data were compared with the data obtained postintubation. Ten patients developed postintubation thallium-perfusion scan defects (thallium-positive scan), even though there was no statistical difference between their baseline hemodynamics and hemodynamics at the time of intubation. There was no difference in the incidence of thallium-positive scans between those patients anesthetized by fentanyl and those patients anesthetized with thiopental-halothane. The authors conclude that relative hypoperfusion, and possibly ischemia, occurred in 45% of patients studied, despite stable hemodynamics, and that the incidence of these events was the same with two different anesthetic techniques

  6. Voltage directive drive with claw pole motor and control without rotor position indicator

    Science.gov (United States)

    Stroenisch, Volker Ewald

    Design and testing of a voltage directive drive for synchronous variable speed claw pole motor and control without rotor position indicator is described. Economic analysis of the designed regulation is performed. Computations of stationary and dynamic behavior are given and experimental operational behavior is determined. The motors can be used for electric transportation vehicles, diesel motors, and electric railway engines.

  7. Small-size low-temperature scanning tunnel microscope

    International Nuclear Information System (INIS)

    Al'tfeder, I.B.; Khajkin, M.S.

    1989-01-01

    A small-size scanning tunnel microscope, designed for operation in transport helium-filled Dewar flasks is described. The microscope design contains a device moving the pin to the tested sample surface and a piezoelectric fine positioning device. High vibration protection of the microscope is provided by its suspension using silk threads. The small-size scanning tunnel microscope provides for atomic resolution

  8. Two unusual causes of peripatellar nonmetastatic positive bone scans in patients with malignancies: case reports

    International Nuclear Information System (INIS)

    Turner, J.W.; Syed, I.B.; Spencer, R.P.

    1976-01-01

    Bone scans performed with /sup 99m/Tc-polyphosphate in two patients with epidermoid carcinoma of the lung each showed activity in one knee area. In the first case, radiographs of the area revealed Pellegrini-Stieda calcification over the internal femoral condyle. Uptake corresponded to this process, rather than to a lesion deep in the bone. In the second case, the activity accumulation in the right tibia was the only abnormality noted in the scan. An open biopsy revealed Paget's disease, and no radiographic evidence of Paget's disease was found in any other bone. These cases again illustrate that localized accumulation of a bone-scanning agent, in patients with known primary tumors, does not necessarily denote malignancy in bone

  9. Over-all accuracy of sup(99m)Tc-pertechnetate brain scanning for brain tumours

    International Nuclear Information System (INIS)

    Bjoernsson, O.G.; Petursson, E.; Sigurbjoernsson, B.; Davidsson, D.

    1978-01-01

    A 3-year follow-up and re-evaluation of all scans on all patients referred for brain scanning in Iceland during 1 year was performed in order to assess the diagnostic reliability of radioisotope scanning for brain tumours. The study included 471 patients. Of these 25 had primary brain tumours and 7 brain metastases. Scans were positive and correctly interpreted in 68% of the patients with primary brain tumours and in 3 of the 7 patients with metastases. The over-all accuracy of brain scanning for brain tumours defined as the total number of correct positive scans and correct negative scans versus total number of scans examined was 96%, this figure being mainly influenced by the high number of true negative scans. (orig.) [de

  10. Scanning holograms

    International Nuclear Information System (INIS)

    Natali, S.

    1984-01-01

    This chapter reports on the scanning of 1000 holograms taken in HOBC at CERN. Each hologram is triggered by an interaction in the chamber, the primary particles being pions at 340 GeV/c. The aim of the experiment is the study of charm production. The holograms, recorded on 50 mm film with the ''in line'' technique, can be analyzed by shining a parallel expanded laser beam through the film, obtaining immediately above it the real image of the chamber which can then be scanned and measured with a technique half way between emulsions and bubble chambers. The results indicate that holograms can be analyzed as quickly and reliably as in other visual techniques and that to them is open the same order of magnitude of large scale experiments

  11. Is scanning in probed order recall articulatory?

    Science.gov (United States)

    Farrell, Simon; Lelièvre, Anna

    2009-09-01

    We consider how theories of serial recall might apply to other short-term memory tasks involving recall of order. In particular, we consider the possibility that when participants are cued to recall an item at an arbitrary position in a sequence, they covertly serially recall the list up to the cued position. One question is whether such "scanning" is articulatory in nature. Two experiments are presented in which the syllabic length of words preceding and following target positions were manipulated, to test the prediction of an articulatory-based mechanism that time to recall an item at a particular position will depend on the number of preceding long words. Although latency was dependent on target position, no word length effects on latency were observed. Additionally, the effects of word length on accuracy replicate recent demonstrations in serial recall that recall accuracy is dependent on the word length of all list items, not just that of target items, in line with distinctiveness assumptions. It is concluded that if scanning does occur, it is not carried out by covert or overt articulation.

  12. Optimization of transmission-scan time for the FixER method: a MR-based PET attenuation correction with a weak fixed-position external radiation source

    Energy Technology Data Exchange (ETDEWEB)

    Kawaguchi, Hiroshi; Hirano, Yoshiyuki; Kershaw, Jeff; Yoshida, Eiji [Molecular Imaging Center, National Institute of Radiological Sciences, Chiba (Japan); Shiraishi, Takahiro [Molecular Imaging Center, National Institute of Radiological Sciences, Chiba (Japan); Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Suga, Mikio [Molecular Imaging Center, National Institute of Radiological Sciences, Chiba (Japan); Center for Frontier Medical Engineering, Chiba University (Japan); Obata, Takayuki [Molecular Imaging Center, National Institute of Radiological Sciences, Chiba (Japan); Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Ito, Hiroshi; Yamaya, Taiga [Molecular Imaging Center, National Institute of Radiological Sciences, Chiba (Japan)

    2014-07-29

    In recent work, we proposed an MRI-based attenuation-coefficient (μ-value) estimation method that uses a weak fixed-position external radiation source to construct an attenuation map for PET/MRI. In this presentation we refer to this method as FixER, and perform a series of simulations to investigate the duration of the transmission scan required to accurately estimate μ-values.

  13. Optimization of transmission-scan time for the FixER method: a MR-based PET attenuation correction with a weak fixed-position external radiation source

    International Nuclear Information System (INIS)

    Kawaguchi, Hiroshi; Hirano, Yoshiyuki; Kershaw, Jeff; Yoshida, Eiji; Shiraishi, Takahiro; Suga, Mikio; Obata, Takayuki; Ito, Hiroshi; Yamaya, Taiga

    2014-01-01

    In recent work, we proposed an MRI-based attenuation-coefficient (μ-value) estimation method that uses a weak fixed-position external radiation source to construct an attenuation map for PET/MRI. In this presentation we refer to this method as FixER, and perform a series of simulations to investigate the duration of the transmission scan required to accurately estimate μ-values.

  14. Navicular bone position determined by positional MRI

    DEFF Research Database (Denmark)

    Hansen, Philip; Johannsen, Finn E; Hangaard, Stine

    2016-01-01

    -scanner). Scanning was performed in supine and standing position, respectively. Two radiologists evaluated the images in a blinded manner. Reliability and agreement were assessed by calculation of intraclass correlation coefficient (ICC) and 95 % limits of agreement as a percentage of the mean (LOA%). RESULTS...

  15. Comparison of pyrophosphate and gluconate scan of dog hearts with experimental cardiomyopathy

    International Nuclear Information System (INIS)

    Duska, F.; Novak, J.; Kafka, P.; Kubicek, J.; Vizda, J.; Mazurova, Y.; Veverkova, O.

    1983-01-01

    High intravenous doses of theophylline with adrenalin were used to produce experimental cardiomyopathy in dogs. This damage was visualized scintigraphically using either sup(99m)Tc-pyrophosphate (10 dogs) or sup(99m)Tc-gluconate (another 10 dogs). Scintigraphic examinations using sup(99m)Tc-pyrophosphate were carried out 48 hours after the damage had developed: in two dogs the examination was negative, in two cases boundary, in 6 cases the scintigraphic finding was clearly positive. sup(99m)Tc-gluconate was used in the examination of 5 animals four hours after the damage had developed. In this case the scan was significantly positive in all cases. The gluconate scan was made 24 hours after damage, again in 5 dogs. Here the positive change was less explicit, in one case the finding was negative. Histological examination of the affected myocardium showed in all cases a very light damage, in many instances on the limit of resolution by light microscopy. The findings were always degenerative (dystrophic) changes and microcirculation disorders without any necrosis. The work showed that both studied radiopharmaceutical preparations are a very sensitive but nonspecific indicator of non-ischemic disorders of the myocardium. For sup(99m)Tc-gluconate this is an original finding. (author)

  16. New nuclear scanning and surveillance systems for global security and safeguards

    International Nuclear Information System (INIS)

    Kemeny, L. G.

    2003-01-01

    This paper discusses new innovative techniques for both cargo and personnel scanning and plant and infrastructure surveillance and protection. It contains Intellectual Property and some of the systems described are covered by Patents. For example, a typical container inspection system is based on Pulsed Fast Neutron Analysis operating on the following principles: 1. An accelerator produced pulses of fast neutrons, which interact with the elemental composition of the cargo under inspection. In a manner similar to radar scanning the timing and positioning of the pulsed neutrons indicates where the interactions occurs. These interactions initiate the emission of gamma radiation which characterises the elemental composition and which is collected by sensor arrays. 2. The gamma ray signals are analysed in a high speed processor which identifies the presence and location of the chemical element combinations in all types of contraband. These may be drugs, explosives or nuclear material. 3. High resolution images display the location and shape of all contraband in the cargo under inspection. An x-ray like image of the cargo can also be provided. Because the scanning system software already contains standard gamma ray material signatures, the need for time consuming and unreliable manual interpretation of complicated images obtained in x-ray scanning systems is completely eliminated

  17. Gallium scans of the thorax in patients with acquired immune deficiency syndrome (AIDS): Description and utilization

    Energy Technology Data Exchange (ETDEWEB)

    Le, G.; Chen, D.C.P.; Siegel, M.E.

    1984-01-01

    The pattern of distribution of gallium uptake in the thorax was investigated in patients (pts) with AIDS. Eleven pts (ages 18-53), all active homosexual males suspected of having acute pulmonary infection were studied. Ga lung scans were performed at 24-48 and/or 72 hrs. post injection. The diagnosis of AIDS was based on appropriate clinical and laboratory findings. The Ga activity in the lung was graded from zero = background to 4+ which is > liver activity. Eight of eleven pts have positive Ga scan while seven of eleven pts had positive CXR. Six pts had both positive CXR and Ga scan. One pt had a positive Ga scan with negative CXR, and one with positive CXR and negative Ga scan. The positive Ga scans included 3 pts with 4+ diffuse uptake, two pts with 2+ diffuse uptake, two pts with 1+ diffuse uptake, and two with hilar node uptake. Three pts have focal increased uptake superimposed on diffuse uptake. Two pts with 4+ diffuse uptake had mild abnormality on their CXR. One pt with 4+ uptake in the initial scan shows decreased activity on follow-up with clinical improvement after therapy. Thus, all but two pts with positive Ga scans had diffuse lung uptake. These two patients alone had B cell immunoblastic sarcoma and oral candidiasis. The pattern of Ga lung uptake in pts with AIDS reveal that a majority of positive scans are diffuse (6/8) and the intensity may suggest more active disease than CXR (2 normal) and, thus, the study may be useful in detecting changes from atypical pulmonary infection in this population.

  18. Gallium scans of the thorax in patients with acquired immune deficiency syndrome (AIDS): Description and utilization

    International Nuclear Information System (INIS)

    Le, G.; Chen, D.C.P.; Siegel, M.E.

    1984-01-01

    The pattern of distribution of gallium uptake in the thorax was investigated in patients (pts) with AIDS. Eleven pts (ages 18-53), all active homosexual males suspected of having acute pulmonary infection were studied. Ga lung scans were performed at 24-48 and/or 72 hrs. post injection. The diagnosis of AIDS was based on appropriate clinical and laboratory findings. The Ga activity in the lung was graded from zero = background to 4+ which is > liver activity. Eight of eleven pts have positive Ga scan while seven of eleven pts had positive CXR. Six pts had both positive CXR and Ga scan. One pt had a positive Ga scan with negative CXR, and one with positive CXR and negative Ga scan. The positive Ga scans included 3 pts with 4+ diffuse uptake, two pts with 2+ diffuse uptake, two pts with 1+ diffuse uptake, and two with hilar node uptake. Three pts have focal increased uptake superimposed on diffuse uptake. Two pts with 4+ diffuse uptake had mild abnormality on their CXR. One pt with 4+ uptake in the initial scan shows decreased activity on follow-up with clinical improvement after therapy. Thus, all but two pts with positive Ga scans had diffuse lung uptake. These two patients alone had B cell immunoblastic sarcoma and oral candidiasis. The pattern of Ga lung uptake in pts with AIDS reveal that a majority of positive scans are diffuse (6/8) and the intensity may suggest more active disease than CXR (2 normal) and, thus, the study may be useful in detecting changes from atypical pulmonary infection in this population

  19. An Evaluation of Two Internal Surrogates for Determining the Three-Dimensional Position of Peripheral Lung Tumors

    International Nuclear Information System (INIS)

    Spoelstra, Femke; Soernsen de Koste, John R. van; Vincent, Andrew; Cuijpers, Johan P.; Slotman, Ben J.; Senan, Suresh

    2009-01-01

    Purpose: Both carina and diaphragm positions have been used as surrogates during respiratory-gated radiotherapy. We studied the correlation of both surrogates with three-dimensional (3D) tumor position. Methods and Materials: A total of 59 repeat artifact-free four-dimensional (4D) computed tomography (CT) scans, acquired during uncoached breathing, were identified in 23 patients with Stage I lung cancer. Repeat scans were co-registered to the initial 4D CT scan, and tumor, carina, and ipsilateral diaphragm were manually contoured in all phases of each 4D CT data set. Correlation between positions of carina and diaphragm with 3D tumor position was studied by use of log-likelihood ratio statistics. Models to predict 3D tumor position from internal surrogates at end inspiration (EI) and end expiration (EE) were developed, and model accuracy was tested by calculating SDs of differences between predicted and actual tumor positions. Results: Motion of both the carina and diaphragm significantly correlated with tumor motion, but log-likelihood ratios indicated that the carina was more predictive for tumor position. When craniocaudal tumor position was predicted by use of craniocaudal carina positions, the SDs of the differences between the predicted and observed positions were 2.2 mm and 2.4 mm at EI and EE, respectively. The corresponding SDs derived with the diaphragm positions were 3.7 mm and 3.9 mm at EI and EE, respectively. Prediction errors in the other directions were comparable. Prediction accuracy was similar at EI and EE. Conclusions: The carina is a better surrogate of 3D tumor position than diaphragm position. Because residual prediction errors were observed in this analysis, additional studies will be performed using audio-coached scans.

  20. Segmentation of Planar Surfaces from Laser Scanning Data Using the Magnitude of Normal Position Vector for Adaptive Neighborhoods.

    Science.gov (United States)

    Kim, Changjae; Habib, Ayman; Pyeon, Muwook; Kwon, Goo-rak; Jung, Jaehoon; Heo, Joon

    2016-01-22

    Diverse approaches to laser point segmentation have been proposed since the emergence of the laser scanning system. Most of these segmentation techniques, however, suffer from limitations such as sensitivity to the choice of seed points, lack of consideration of the spatial relationships among points, and inefficient performance. In an effort to overcome these drawbacks, this paper proposes a segmentation methodology that: (1) reduces the dimensions of the attribute space; (2) considers the attribute similarity and the proximity of the laser point simultaneously; and (3) works well with both airborne and terrestrial laser scanning data. A neighborhood definition based on the shape of the surface increases the homogeneity of the laser point attributes. The magnitude of the normal position vector is used as an attribute for reducing the dimension of the accumulator array. The experimental results demonstrate, through both qualitative and quantitative evaluations, the outcomes' high level of reliability. The proposed segmentation algorithm provided 96.89% overall correctness, 95.84% completeness, a 0.25 m overall mean value of centroid difference, and less than 1° of angle difference. The performance of the proposed approach was also verified with a large dataset and compared with other approaches. Additionally, the evaluation of the sensitivity of the thresholds was carried out. In summary, this paper proposes a robust and efficient segmentation methodology for abstraction of an enormous number of laser points into plane information.

  1. 67Ga lung scan

    International Nuclear Information System (INIS)

    Niden, A.H.; Mishkin, F.S.; Khurana, M.M.L.; Pick, R.

    1977-01-01

    Twenty-three patients with clinical signs of pulmonary embolic disease and lung infiltrates were studied to determine the value of gallium citrate 67 Ga lung scan in differentiating embolic from inflammatory lung disease. In 11 patients without angiographically proved embolism, only seven had corresponding ventilation-perfusion defects compatible with inflammatory disease. In seven of these 11 patients, the 67 Ga concentration indicated inflammatory disease. In the 12 patients with angiographically proved embolic disease, six had corresponding ventilation-perfusion defects compatible with inflammatory disease. None had an accumulation of 67 Ga in the area of pulmonary infiltrate. Thus, ventilation-perfusion lung scans are of limited value when lung infiltrates are present. In contrast, the accumulation of 67 Ga in the lung indicates an inflammatory process. Gallium imaging can help select those patients with lung infiltrates who need angiography

  2. Simulating Various Terrestrial and Uav LIDAR Scanning Configurations for Understory Forest Structure Modelling

    Science.gov (United States)

    Hämmerle, M.; Lukač, N.; Chen, K.-C.; Koma, Zs.; Wang, C.-K.; Anders, K.; Höfle, B.

    2017-09-01

    Information about the 3D structure of understory vegetation is of high relevance in forestry research and management (e.g., for complete biomass estimations). However, it has been hardly investigated systematically with state-of-the-art methods such as static terrestrial laser scanning (TLS) or laser scanning from unmanned aerial vehicle platforms (ULS). A prominent challenge for scanning forests is posed by occlusion, calling for proper TLS scan position or ULS flight line configurations in order to achieve an accurate representation of understory vegetation. The aim of our study is to examine the effect of TLS or ULS scanning strategies on (1) the height of individual understory trees and (2) understory canopy height raster models. We simulate full-waveform TLS and ULS point clouds of a virtual forest plot captured from various combinations of max. 12 TLS scan positions or 3 ULS flight lines. The accuracy of the respective datasets is evaluated with reference values given by the virtually scanned 3D triangle mesh tree models. TLS tree height underestimations range up to 1.84 m (15.30 % of tree height) for single TLS scan positions, but combining three scan positions reduces the underestimation to maximum 0.31 m (2.41 %). Combining ULS flight lines also results in improved tree height representation, with a maximum underestimation of 0.24 m (2.15 %). The presented simulation approach offers a complementary source of information for efficient planning of field campaigns aiming at understory vegetation modelling.

  3. SIMULATING VARIOUS TERRESTRIAL AND UAV LIDAR SCANNING CONFIGURATIONS FOR UNDERSTORY FOREST STRUCTURE MODELLING

    Directory of Open Access Journals (Sweden)

    M. Hämmerle

    2017-09-01

    Full Text Available Information about the 3D structure of understory vegetation is of high relevance in forestry research and management (e.g., for complete biomass estimations. However, it has been hardly investigated systematically with state-of-the-art methods such as static terrestrial laser scanning (TLS or laser scanning from unmanned aerial vehicle platforms (ULS. A prominent challenge for scanning forests is posed by occlusion, calling for proper TLS scan position or ULS flight line configurations in order to achieve an accurate representation of understory vegetation. The aim of our study is to examine the effect of TLS or ULS scanning strategies on (1 the height of individual understory trees and (2 understory canopy height raster models. We simulate full-waveform TLS and ULS point clouds of a virtual forest plot captured from various combinations of max. 12 TLS scan positions or 3 ULS flight lines. The accuracy of the respective datasets is evaluated with reference values given by the virtually scanned 3D triangle mesh tree models. TLS tree height underestimations range up to 1.84 m (15.30 % of tree height for single TLS scan positions, but combining three scan positions reduces the underestimation to maximum 0.31 m (2.41 %. Combining ULS flight lines also results in improved tree height representation, with a maximum underestimation of 0.24 m (2.15 %. The presented simulation approach offers a complementary source of information for efficient planning of field campaigns aiming at understory vegetation modelling.

  4. Scan posture definition and hip girth measurement: the impact on clothing design and body scanning.

    Science.gov (United States)

    Gill, Simeon; Parker, Christopher J

    2017-08-01

    Ergonomic measurement is central to product design and development; especially for body worn products and clothing. However, there is a large variation in measurement definitions, complicated by new body scanning technology that captures measurements in a posture different to traditional manual methods. Investigations of hip measurement definitions in current clothing measurement practices supports analysis of the effect of scan posture and hip measurement definition on the circumferences of the hip. Here, the hip girth is a key clothing measurement that is not defined in current body scanning measurement standards. Sixty-four participants were scanned in the standard scan posture of a [TC] 2 body scanner, and also in a natural posture similar to that of traditional manual measurement collection. Results indicate that scan posture affects hip girth circumferences, and that some current clothing measurement practices may not define the largest lower body circumference. Recommendations are made concerning how the hip is defined in measurement practice and within body scanning for clothing product development. Practitioner Summary: The hip girth is an important measurement in garment design, yet its measurement protocol is not currently defined. We demonstrate that body posture during body scanning affects hip circumferences, and that current clothing measurement practices may not define the largest lower body circumference. This paper also provides future measurement practice recommendations.

  5. Experimental study on pure titanium during the positive-torsion and positive-negative-torsion

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Han; Li, Fuguo, E-mail: fuguolx@nwpu.edu.cn; Li, Jinghui; Zhao, Zhen; Zhou, Shunshun; Wan, Qiong

    2016-09-30

    The results of the mechanical properties, microstructure and fracture analysis of the pure titanium deformed by positive-torsion (PT) and positive-negative-torsion (PNT) are investigated by uniaxial tensile (UT) test, micro-indentation (MI) test, optical microscope (OM), transmission electron microscope (TEM) and scanning electron microscope (SEM). The UT test indicates that the strength increases obviously with the increase of torsion radian during PT. However, the strength firstly increases quickly, and then tends to steady with the increase of deformation during PNT. The similar phenomena are also shown through MI hardness analysis. The results from geometrically necessary dislocations (GNDs) and statistically stored dislocations (SSDs) indicate that the dislocation density varies differently with the increase of deformation during PT and PNT. OM observation shows the grains are elongated and large numbers of deformation twins are observed during PT while the equiaxial grains are always presented during PNT. The variations of dislocation density during PT and PNT are verified by TEM. Besides, quantities of subgrains (SGs) are observed owing to the accumulated larger plastic strain during PNT while large numbers of deformation twins intersect with each other during PT. The fracture analysis indicates that large numbers of micro-voids distribute non-uniformly on fracture surface of sample twisted by PNT. However, the characteristics of ductile and brittle fracture are observed on fracture surface of sample twisted by PT.

  6. Intracochlear Position of Cochlear Implants Determined Using CT Scanning versus Fitting Levels: Higher Threshold Levels at Basal Turn.

    Science.gov (United States)

    van der Beek, Feddo B; Briaire, Jeroen J; van der Marel, Kim S; Verbist, Berit M; Frijns, Johan H M

    2016-01-01

    In this study, the effects of the intracochlear position of cochlear implants on the clinical fitting levels were analyzed. A total of 130 adult subjects who used a CII/HiRes 90K cochlear implant with a HiFocus 1/1J electrode were included in the study. The insertion angle and the distance to the modiolus of each electrode contact were determined using high-resolution CT scanning. The threshold levels (T-levels) and maximum comfort levels (M-levels) at 1 year of follow-up were determined. The degree of speech perception of the subjects was evaluated during routine clinical follow-up. The depths of insertion of all the electrode contacts were determined. The distance to the modiolus was significantly smaller at the basal and apical cochlear parts compared with that at the middle of the cochlea (p basal end of the cochlea (3.4 dB). Additionally, the M-levels, which were fitted in our clinic using a standard profile, also increased toward the basal end, although with a lower amplitude (1.3 dB). Accordingly, the dynamic range decreased toward the basal end (2.1 dB). No correlation was found between the distance to the modiolus and the T-level or the M-level. Furthermore, the correlation between the insertion depth and stimulation levels was not affected by the duration of deafness, age at implantation or the time since implantation. Additionally, the T-levels showed a significant correlation with the speech perception scores (p stimulation levels of the cochlear implants were affected by the intracochlear position of the electrode contacts, which were determined using postoperative CT scanning. Interestingly, these levels depended on the insertion depth, whereas the distance to the modiolus did not affect the stimulation levels. The T-levels increased toward the basal end of the cochlea. The level profiles were independent of the overall stimulation levels and were not affected by the biographical data of the patients, such as the duration of deafness, age at

  7. Is decreased diameter of renal pelvis in prone position an indicator of successful pyeloplasty?

    International Nuclear Information System (INIS)

    Sharma, Gyanendra; Sharma, Anshu; Leung, Vivian Yee-Fong; Chu, Winnie Chiu-Wing

    2016-01-01

    To evaluate patients who had undergone pyeloplasty for pelviureteric junction obstruction, by measuring the anteroposterior diameter (APD) of the renal pelvis in supine and prone positions, and determine whether a decrease in APD in prone position can exclude obstruction in dilated renal system. From January 2012 to December 2013, patients who had undergone pyeloplasty were evaluated by ultrasound in two centers. The difference of APD of the renal pelvis in supine and prone positions was obtained. Correlation was made with the pre- and post-pyeloplasty renal function by radionuclide renogram. There were 42 patients (31 males, 11 females; age range 5 months to 18 years). Residual hydronephrosis was detected in 41 patients of whom 35 patients (85%) showed decrease in APD by >10% in prone position. These patients and the one without hydronephrosis showed either no deterioration or improvement in renal function. Six patients (15%) showed either no change or increase in APD in prone position. Three patients (7.5%) were confirmed to have decrease in renal function indicating obstruction. Three patients (7.5%) showed no deterioration of renal function, but sluggish drainage on radionuclide renogram. Demonstration of decreased APD of renal pelvis in prone position by ultrasound is useful to differentiate obstructed from non-obstructed dilated renal system, and it correctly identified 85% candidates with successful pyeloplasty. In patients with no decrease or increase in APD at prone position, further follow-up is recommended to rule out obstruction

  8. Mouse manipulation through single-switch scanning.

    Science.gov (United States)

    Blackstien-Adler, Susie; Shein, Fraser; Quintal, Janet; Birch, Shae; Weiss, Patrice L Tamar

    2004-01-01

    Given the current extensive reliance on the graphical user interface, independent access to computer software requires that users be able to manipulate a pointing device of some type (e.g., mouse, trackball) or be able to emulate a mouse by some other means (e.g., scanning). The purpose of the present study was to identify one or more optimal single-switch scanning mouse emulation strategies. Four alternative scanning strategies (continuous Cartesian, discrete Cartesian, rotational, and hybrid quadrant/continuous Cartesian) were selected for testing based on current market availability as well as on theoretical considerations of their potential speed and accuracy. Each strategy was evaluated using a repeated measures study design by means of a test program that permitted mouse emulation via any one of four scanning strategies in a motivating environment; response speed and accuracy could be automatically recorded and considered in view of the motor, cognitive, and perceptual demands of each scanning strategy. Ten individuals whose disabilities required them to operate a computer via single-switch scanning participated in the study. Results indicated that Cartesian scanning was the preferred and most effective scanning strategy. There were no significant differences between results from the Continuous Cartesian and Discrete Cartesian scanning strategies. Rotational scanning was quite slow with respect to the other strategies, although it was equally accurate. Hybrid Quadrant scanning improved access time but at the cost of fewer correct selections. These results demonstrated the importance of testing and comparing alternate single-switch scanning strategies.

  9. Significance of leukocyte scanning in infected endoprostheses

    Energy Technology Data Exchange (ETDEWEB)

    Becker, W.; Pasurka, B.; Boerner, W.

    1989-03-01

    31 patients with suspected septic loosening of an endoprosthesis (hip endoprosthesis n=30; knee endoprosthesis n=1) were examined with leukocyte scans (10 MBq /sup 111/In-oxine: n=22; 300 MBq /sup 99m/Tc-HMPAO: n=9). The results were compared with results of the bacterial growth (n=22), the histology (n=12) and of the bone scans (/sup 99m/Tc-MDP: n=20) which were performed within 4 days. The sensitivity of the bone scan was 100%, the specificity 30% and the diagnostic accuracy regarding a septic loosening of the arthroplasty was 55%. For the leukocyte scans a comparable sensitivity of 100%, but a higher specificity (86%) and accuracy (91%) could be calculated. A false positive leukocyte scan could be observed in a periprosthetic granuloma, an ossifying periarthritis and in a patient with negative bacterial growth with the histological proof of an inflammation.

  10. Colorectal cancer detection by hyperspectral imaging using fluorescence excitation scanning

    Science.gov (United States)

    Leavesley, Silas J.; Deal, Joshua; Hill, Shante; Martin, Will A.; Lall, Malvika; Lopez, Carmen; Rider, Paul F.; Rich, Thomas C.; Boudreaux, Carole W.

    2018-02-01

    Hyperspectral imaging technologies have shown great promise for biomedical applications. These techniques have been especially useful for detection of molecular events and characterization of cell, tissue, and biomaterial composition. Unfortunately, hyperspectral imaging technologies have been slow to translate to clinical devices - likely due to increased cost and complexity of the technology as well as long acquisition times often required to sample a spectral image. We have demonstrated that hyperspectral imaging approaches which scan the fluorescence excitation spectrum can provide increased signal strength and faster imaging, compared to traditional emission-scanning approaches. We have also demonstrated that excitation-scanning approaches may be able to detect spectral differences between colonic adenomas and adenocarcinomas and normal mucosa in flash-frozen tissues. Here, we report feasibility results from using excitation-scanning hyperspectral imaging to screen pairs of fresh tumoral and nontumoral colorectal tissues. Tissues were imaged using a novel hyperspectral imaging fluorescence excitation scanning microscope, sampling a wavelength range of 360-550 nm, at 5 nm increments. Image data were corrected to achieve a NIST-traceable flat spectral response. Image data were then analyzed using a range of supervised and unsupervised classification approaches within ENVI software (Harris Geospatial Solutions). Supervised classification resulted in >99% accuracy for single-patient image data, but only 64% accuracy for multi-patient classification (n=9 to date), with the drop in accuracy due to increased false-positive detection rates. Hence, initial data indicate that this approach may be a viable detection approach, but that larger patient sample sizes need to be evaluated and the effects of inter-patient variability studied.

  11. SU-C-12A-07: Effect of Vertical Position On Dose Reduction Using X-Care

    International Nuclear Information System (INIS)

    Silosky, M; Marsh, R

    2014-01-01

    Purpose: Reduction of absorbed dose to radiosensitive tissues is an important goal in diagnostic radiology. Siemens Medical has introduced a technique (X-CARE) to lower CT dose to anterior anatomy by reducing the tube current during 80° of rotation over radiosensitive tissues. Phantom studies have shown 30-40% dose reduction when phantoms are positioned at isocenter. However, for CT face and sinus exams, the center of the head is commonly positioned below isocenter. This work investigated the effects of vertical patient positioning on dose reduction using X-CARE. Methods: A 16cm Computed Tomography Dose Index phantom was scanned on a Siemens Definition Flash CT scanner using a routine head protocol, with the phantom positioned at scanner isocenter. Optically stimulated luminescent dosimeters were placed on the anterior and posterior sides of the phantom. The phantom was lowered in increments of 2cm and rescanned, up to 8cm below isocenter. The experiment was then repeated using the same scan parameters but adding the X-CARE technique. The mean dosimeter counts were determined for each phantom position, and the difference between XCARE and routine scans was plotted as a function of distance from isocenter. Results: With the phantom positioned at isocenter, using XCARE reduced dose to the anterior side of the phantom by 40%, compared to dose when X-CARE was not used. Positioned below isocenter, anterior dose was reduced by only 20-27%. Additionally, using X-CARE at isocenter reduced dose to the anterior portion of the phantom by 45.6% compared to scans performed without X-CARE 8cm below isocenter. Conclusion: While using X-CARE substantially reduced dose to the anterior side of the phantom, this effect was diminished when the phantom was positioned below isocenter, simulating common practice for face and sinus scans. This indicates that centering the head in the gantry will maximize the effect of X-CARE

  12. The sensitivity of computed tomography (CT) scans in detecting trauma: are CT scans reliable enough for courtroom testimony?

    Science.gov (United States)

    Molina, D Kimberley; Nichols, Joanna J; Dimaio, Vincent J M

    2007-09-01

    Rapid and accurate recognition of traumatic injuries is extremely important in emergency room and surgical settings. Emergency departments depend on computed tomography (CT) scans to provide rapid, accurate injury assessment. We conducted an analysis of all traumatic deaths autopsied at the Bexar County Medical Examiner's Office in which perimortem medical imaging (CT scan) was performed to assess the reliability of the CT scan in detecting trauma with sufficient accuracy for courtroom testimony. Cases were included in the study if an autopsy was conducted, a CT scan was performed within 24 hours before death, and there was no surgical intervention. Analysis was performed to assess the correlation between the autopsy and CT scan results. Sensitivity, specificity, positive predictive value, and negative predictive value were defined for the CT scan based on the autopsy results. The sensitivity of the CT scan ranged from 0% for cerebral lacerations, cervical vertebral body fractures, cardiac injury, and hollow viscus injury to 75% for liver injury. This study reveals that CT scans are an inadequate detection tool for forensic pathologists, where a definitive diagnosis is required, because they have a low level of accuracy in detecting traumatic injuries. CT scans may be adequate for clinicians in the emergency room setting, but are inadequate for courtroom testimony. If the evidence of trauma is based solely on CT scan reports, there is a high possibility of erroneous accusations, indictments, and convictions.

  13. Variants and pitfalls on radioiodine scans in pediatric patients with differentiated thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Mostafa, Mohamed; Vali, Reza; Chan, Jeffrey; Omarkhail, Yusuaf; Shammas, Amer [University of Toronto, Nuclear Medicine Division, Department of Medical Imaging, The Hospital for Sick Children, Toronto, Ontario (Canada)

    2016-10-15

    Potentially false-positive findings on radioiodine scans in children with differentiated thyroid carcinoma can mimic functioning thyroid tissue and functioning thyroid carcinomatous tissue. Such false-positive findings comprise variants and pitfalls that can vary slightly in children as compared with adults. To determine the patterns and frequency of these potential false-positive findings on radioiodine scans in children with differentiated thyroid carcinoma. We reviewed a total of 223 radioiodine scans from 53 pediatric patients (mean age 13.3 years, 37 girls) with differentiated thyroid carcinoma. Focal or regional activity that likely did not represent functioning thyroid tissue or functioning thyroid carcinomatous tissue were categorized as variants or pitfalls. The final diagnosis was confirmed by reviewing the concurrent and follow-up clinical data, correlative ultrasonography, CT scanning, serum thyroglobulin and antithyroglobulin antibody levels. We calculated the frequency of these variants and pitfalls from diagnostic and post-therapy radioiodine scans. The most common variant on the radioiodine scans was the thymic activity (24/223, 10.8%) followed by the cardiac activity (8/223, 3.6%). Salivary contamination and star artifact, caused by prominent thyroid remnant, were the most important observed pitfalls. Variants and pitfalls that mimic functioning thyroid tissue or functioning thyroid carcinomatous tissue on radioiodine scan in children with differentiated thyroid carcinoma are not infrequent, but they decrease in frequency on successive radioiodine scans. Potential false-positive findings can be minimized with proper knowledge of the common variants and pitfalls in children and correlation with clinical, laboratory and imaging data. (orig.)

  14. Analysis the findings of chest radiograph and CT scan in 217 acute thoracic trauma

    International Nuclear Information System (INIS)

    Huang Shaoying

    2005-01-01

    Objective: To evaluate chest radiograph and CT scan in assessing acute thoracic trauma. Methods: Retrospectively analyzed the findings of chest radiograph and CT scan in 217 cases of acute thoracic trauma and positive rate of each modality was compared. Results: The positive rate of rib and clavicle fracture was higher in chest radiograph than these in CT scan. But the positive rate of chest wall hematoma, mediastinum and subcutaneous emphysema, pneumothorax, hydropneumothorax, damage of lung parenchyma and traumatic pulmonary atelectasis was higher in CT scan than those in chest radiograph. Conclusion: The application of the combined imaging modalities improves assessing of acute thoracic trauma, because the imaging manifestation of the lesion is various. (authors)

  15. Slope excavation quality assessment and excavated volume calculation in hydraulic projects based on laser scanning technology

    Directory of Open Access Journals (Sweden)

    Chao Hu

    2015-04-01

    Full Text Available Slope excavation is one of the most crucial steps in the construction of a hydraulic project. Excavation project quality assessment and excavated volume calculation are critical in construction management. The positioning of excavation projects using traditional instruments is inefficient and may cause error. To improve the efficiency and precision of calculation and assessment, three-dimensional laser scanning technology was used for slope excavation quality assessment. An efficient data acquisition, processing, and management workflow was presented in this study. Based on the quality control indices, including the average gradient, slope toe elevation, and overbreak and underbreak, cross-sectional quality assessment and holistic quality assessment methods were proposed to assess the slope excavation quality with laser-scanned data. An algorithm was also presented to calculate the excavated volume with laser-scanned data. A field application and a laboratory experiment were carried out to verify the feasibility of these methods for excavation quality assessment and excavated volume calculation. The results show that the quality assessment indices can be obtained rapidly and accurately with design parameters and scanned data, and the results of holistic quality assessment are consistent with those of cross-sectional quality assessment. In addition, the time consumption in excavation quality assessment with the laser scanning technology can be reduced by 70%–90%, as compared with the traditional method. The excavated volume calculated with the scanned data only slightly differs from measured data, demonstrating the applicability of the excavated volume calculation method presented in this study.

  16. Home continuous positive airway pressure for cardiopulmonary indications in infants and children.

    Science.gov (United States)

    Al-Iede, Montaha; Kumaran, Radhagini; Waters, Karen

    2018-04-30

    A number of reports exist regarding the use of continuous positive airway pressure (CPAP) to manage obstructive sleep apnoea (OSA) in children, which we term 'conventional CPAP'. In contrast, there are few reports of home CPAP use for other indications, which we have grouped under the term 'cardiopulmonary'. The aims of this study were to (1) document cardiopulmonary indications for CPAP use in a cohort of infants and children, and (2) evaluate its effectiveness in this group. Hospital records were reviewed for 645 patients who were commenced on long-term CPAP over a 10-year period at a single-tertiary hospital (Children's Hospital at Westmead). This study evaluated the group where the primary indication for CPAP was not OSA ('cardiopulmonary CPAP'). Data evaluated included: demographics, diagnoses, indications for CPAP, hours of use (compliance) and sleep study results at baseline and on CPAP. Of 645 children, 148 (23%) used home CPAP for cardiopulmonary indications; and 130 (87.8%) of these were included. For this group, mean age at CPAP initiation was 18.6 ± 33.6 months (range one week to 16.8 years). Cardiopulmonary indications for CPAP use included: primary airway diseases 65 (50%), chronic lung diseases 33 (25.4%), congenital heart disease (CHD) 20 (15.4%), and both CHD and airway malacia 12 (9.2%). All sleep study variables improved on CPAP relative to the diagnostic sleep study (p 4 h/night). Interstitial lung diseases and other cardiorespiratory disorders, often of congenital origin, can be effectively treated with home CPAP whether they are associated with OSA or not. Sleep studies demonstrated improved gas exchange, sleep and reduced work of breathing with CPAP use. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Laser scanning of experimental solar cells

    Science.gov (United States)

    Plunkett, B. C.; Lasswell, P. G.

    1980-01-01

    A description is presented of a laser scanning instrument which makes it possible to display and measure the spatial response of a solar cell. Examples are presented to illustrate the use of generated micrographs in the isolation of flaws and features of the cell. The laser scanner system uses a 4 mW, CW helium-neon laser, operating a wavelength of 0.633 micrometers. The beam is deflected by two mirror galvanometers arranged to scan in orthogonal directions. After being focused on the solar cell by the beam focusing lens, the moving light spot raster scans the specimen. The current output of the photovoltaic device under test, as a function of the scan dot position, can be displayed in several modes. The laser scanner has proved to be a very useful diagnostic tool in optimizing the process design of transparent metal film photovoltaic devices on Zn3P2, a relatively new photovoltaic material.

  18. Bridging centrality: A new indicator to measure the positioning of actors in R&D networks

    Energy Technology Data Exchange (ETDEWEB)

    Scherngell, T.; Wanzenboeck, I.; Berge, L.

    2016-07-01

    In the recent past, we can observe growing interest in the STI community in the notion of positioning indicators, shifting emphasis to actors in the innovation process and their R&D inter-linkages with other actors. In relation to this, we suggest a new approach for assessing the positioning of actors relying on the notion of bridging centrality (BC). Based on the concept of bridging paths, i.e. a set of two links connecting three actors across three different aggregate nodes (e.g. organisations, regions or countries), we argue that triangulation in networks is a key issue for knowledge recombinations and the extension of an actor's knowledge base. As bridges are most often not empirically observable at the individual level of research teams, we propose an approximated BC measure that provides a flexible framework for dealing with the aggregation problem in positioning actors. Hereby, BC is viewed as a function of an aggregate node's (i) participation intensity in the network, (ii) its openness to other nodes (i.e. the relative outward orientation of network links), and iii) the diversification of links to other nodes. In doing so, we provide an integrative perspective that enables us to achieve a better understanding of the positioning of certain actors in R&D networks. An illustrative example on the co-patent network of European regions demonstrates the performance and usefulness of our BC measure for networks constructed at the aggregated level, i.e. regions in our example. A region's outward orientation and the diversification of its network links moderates the influence of regional scale on network centrality. This is a major strength of the measure, and it paves the way for future studies to examine the role of certain aggregate node's, and, by this, contributes to the debate on positioning indicators in the STI context. (Author)

  19. Segmentation of Planar Surfaces from Laser Scanning Data Using the Magnitude of Normal Position Vector for Adaptive Neighborhoods

    Directory of Open Access Journals (Sweden)

    Changjae Kim

    2016-01-01

    Full Text Available Diverse approaches to laser point segmentation have been proposed since the emergence of the laser scanning system. Most of these segmentation techniques, however, suffer from limitations such as sensitivity to the choice of seed points, lack of consideration of the spatial relationships among points, and inefficient performance. In an effort to overcome these drawbacks, this paper proposes a segmentation methodology that: (1 reduces the dimensions of the attribute space; (2 considers the attribute similarity and the proximity of the laser point simultaneously; and (3 works well with both airborne and terrestrial laser scanning data. A neighborhood definition based on the shape of the surface increases the homogeneity of the laser point attributes. The magnitude of the normal position vector is used as an attribute for reducing the dimension of the accumulator array. The experimental results demonstrate, through both qualitative and quantitative evaluations, the outcomes’ high level of reliability. The proposed segmentation algorithm provided 96.89% overall correctness, 95.84% completeness, a 0.25 m overall mean value of centroid difference, and less than 1° of angle difference. The performance of the proposed approach was also verified with a large dataset and compared with other approaches. Additionally, the evaluation of the sensitivity of the thresholds was carried out. In summary, this paper proposes a robust and efficient segmentation methodology for abstraction of an enormous number of laser points into plane information.

  20. Indium-111-labeled leukocyte scan in detection of synthetic vascular graft infection: The effect of antibiotic treatment

    International Nuclear Information System (INIS)

    Chung, C.J.; Hicklin, O.A.; Payan, J.M.; Gordon, L.

    1991-01-01

    To determine the sensitivity and specificity of the indium-111-( 111 In) labeled leukocyte scan for prosthetic vascular graft infection in patients treated with antibiotic therapy, a retrospective study was performed. Of 41 consecutive 111 In-labeled leukocyte scans performed to evaluate possible vascular graft infection, 23 scans were performed in patients treated with antibiotics. The average duration of antibiotic therapy was 21 days. Twelve positive and 11 negative scans for graft infection were found. By surgical and autopsy correlation of all positive cases, and clinical correlation (of all negative cases), there were 10 true-positive, 11 true-negative, 2 false-positive, and no false-negative scans for graft infections, for an overall sensitivity of 100% and specificity of 85%

  1. Commissioning of output factors for uniform scanning proton beams

    International Nuclear Information System (INIS)

    Zheng Yuanshui; Ramirez, Eric; Mascia, Anthony; Ding Xiaoning; Okoth, Benny; Zeidan, Omar; Hsi Wen; Harris, Ben; Schreuder, Andries N.; Keole, Sameer

    2011-01-01

    Purpose: Current commercial treatment planning systems are not able to accurately predict output factors and calculate monitor units for proton fields. Patient-specific field output factors are thus determined by either measurements or empirical modeling based on commissioning data. The objective of this study is to commission output factors for uniform scanning beams utilized at the ProCure proton therapy centers. Methods: Using water phantoms and a plane parallel ionization chamber, the authors first measured output factors with a fixed 10 cm diameter aperture as a function of proton range and modulation width for clinically available proton beams with ranges between 4 and 31.5 cm and modulation widths between 2 and 15 cm. The authors then measured the output factor as a function of collimated field size at various calibration depths for proton beams of various ranges and modulation widths. The authors further examined the dependence of the output factor on the scanning area (i.e., uncollimated proton field), snout position, and phantom material. An empirical model was developed to calculate the output factor for patient-specific fields and the model-predicted output factors were compared to measurements. Results: The output factor increased with proton range and field size, and decreased with modulation width. The scanning area and snout position have a small but non-negligible effect on the output factors. The predicted output factors based on the empirical modeling agreed within 2% of measurements for all prostate treatment fields and within 3% for 98.5% of all treatment fields. Conclusions: Comprehensive measurements at a large subset of available beam conditions are needed to commission output factors for proton therapy beams. The empirical modeling agrees well with the measured output factor data. This investigation indicates that it is possible to accurately predict output factors and thus eliminate or reduce time-consuming patient-specific output

  2. A laser sheet self-calibration method for scanning PIV

    Science.gov (United States)

    Knutsen, Anna N.; Lawson, John M.; Dawson, James R.; Worth, Nicholas A.

    2017-10-01

    Knowledge of laser sheet position, orientation, and thickness is a fundamental requirement of scanning PIV and other laser-scanning methods. This paper describes the development and evaluation of a new laser sheet self-calibration method for stereoscopic scanning PIV, which allows the measurement of these properties from particle images themselves. The approach is to fit a laser sheet model by treating particles as randomly distributed probes of the laser sheet profile, whose position is obtained via a triangulation procedure enhanced by matching particle images according to their variation in brightness over a scan. Numerical simulations and tests with experimental data were used to quantify the sensitivity of the method to typical experimental error sources and validate its performance in practice. The numerical simulations demonstrate the accurate recovery of the laser sheet parameters over range of different seeding densities and sheet thicknesses. Furthermore, they show that the method is robust to significant image noise and camera misalignment. Tests with experimental data confirm that the laser sheet model can be accurately reconstructed with no impairment to PIV measurement accuracy. The new method is more efficient and robust in comparison with the standard (self-) calibration approach, which requires an involved, separate calibration step that is sensitive to experimental misalignments. The method significantly improves the practicality of making accurate scanning PIV measurements and broadens its potential applicability to scanning systems with significant vibrations.

  3. A fluorescent screen + CCD system for quality assurance of therapeutic scanned ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Takeshita, E., E-mail: eriuli@nirs.go.jp [National Institute of Radiological Sciences, Chiba (Japan); Furukawa, T., E-mail: t_furu@nirs.go.jp [National Institute of Radiological Sciences, Chiba (Japan); Inaniwa, T., E-mail: taku@nirs.go.jp [National Institute of Radiological Sciences, Chiba (Japan); Sato, S., E-mail: shin_s@nirs.go.jp [National Institute of Radiological Sciences, Chiba (Japan); Himukai, T., E-mail: himukai@nirs.go.jp [National Institute of Radiological Sciences, Chiba (Japan); Shirai, T., E-mail: t_shirai@nirs.go.jp [National Institute of Radiological Sciences, Chiba (Japan); Noda, K., E-mail: noda_k@nirs.go.jp [National Institute of Radiological Sciences, Chiba (Japan)

    2011-12-15

    A fluorescent screen + a charge coupled device (CCD) system were developed to verify the performance of scanned ion beams at the HIMAC. The fluorescent light from the screen is observed by the CCD camera. Two-dimensional fields, produced by the scanning process, i.e., the position and the size of the beam for each scan, represent of the important issues in scanning irradiation. In the developed system, the two-dimensional relative fluence and the flatness of the irradiation field were measured in a straightforward technique from the luminance distribution on the screen. The position and the size of the beams were obtained from centroid computation results of the brightness. By the good sensitivity and spatial resolution of the fluorescent screen + CCD system, the scanned ion beams were verified as the measurements at the HIMAC prototype scanning system.

  4. A fluorescent screen + CCD system for quality assurance of therapeutic scanned ion beams

    Science.gov (United States)

    Takeshita, E.; Furukawa, T.; Inaniwa, T.; Sato, S.; Himukai, T.; Shirai, T.; Noda, K.

    2011-12-01

    A fluorescent screen + a charge coupled device (CCD) system were developed to verify the performance of scanned ion beams at the HIMAC. The fluorescent light from the screen is observed by the CCD camera. Two-dimensional fields, produced by the scanning process, i.e., the position and the size of the beam for each scan, represent of the important issues in scanning irradiation. In the developed system, the two-dimensional relative fluence and the flatness of the irradiation field were measured in a straightforward technique from the luminance distribution on the screen. The position and the size of the beams were obtained from centroid computation results of the brightness. By the good sensitivity and spatial resolution of the fluorescent screen + CCD system, the scanned ion beams were verified as the measurements at the HIMAC prototype scanning system.

  5. Measuring socio-economic position in dietary research: is choice of socio-economic indicator important?

    Science.gov (United States)

    Turrell, Gavin; Hewitt, Belinda; Patterson, Carla; Oldenburg, Brian

    2003-04-01

    To examine the association between socio-economic position (SEP) and diet, by assessing the unadjusted and simultaneously adjusted (independent) contributions of education, occupation and household income to food purchasing behaviour. The sample was randomly selected using a stratified two-stage cluster design, and the response rate was 66.4%. Data were collected by face-to-face interview. Food purchasing was examined on the basis of three composite indices that reflected a household's choice of grocery items (including meat and chicken), fruit and vegetables. Brisbane City, Australia, 2000. : Non-institutionalised residents of private dwellings located in 50 small areas (Census Collectors Districts). When shopping, respondents in lower socio-economic groups were less likely to purchase grocery foods that were high in fibre and low in fat, salt and sugar. Disadvantaged groups purchased fewer types of fresh fruits and vegetables, and less often, than their counterparts from more advantaged backgrounds. When the relationship between SEP and food purchasing was examined using each indicator separately, education and household income made an unadjusted contribution to purchasing behaviour for all three food indices; however, occupation was significantly related only with the purchase of grocery foods. When education and occupation were simultaneously adjusted for each other, the socio-economic patterning with food purchase remained largely unchanged, although the strength of the associations was attenuated. When household income was introduced into the analysis, the association between education, occupation and food purchasing behaviour was diminished or became non-significant; income, however, showed a strong, graded association with food choice. The food purchasing behaviours of socio-economically disadvantaged groups were least in accord with dietary guideline recommendations, and hence are more consistent with greater risk for the development of diet

  6. Hi-Res scan mode in clinical MDCT systems: Experimental assessment of spatial resolution performance.

    Science.gov (United States)

    Cruz-Bastida, Juan P; Gomez-Cardona, Daniel; Li, Ke; Sun, Heyi; Hsieh, Jiang; Szczykutowicz, Timothy P; Chen, Guang-Hong

    2016-05-01

    The introduction of a High-Resolution (Hi-Res) scan mode and another associated option that combines Hi-Res mode with the so-called High Definition (HD) reconstruction kernels (referred to as a Hi-Res/HD mode in this paper) in some multi-detector CT (MDCT) systems offers new opportunities to increase spatial resolution for some clinical applications that demand high spatial resolution. The purpose of this work was to quantify the in-plane spatial resolution along both the radial direction and tangential direction for the Hi-Res and Hi-Res/HD scan modes at different off-center positions. A technique was introduced and validated to address the signal saturation problem encountered in the attempt to quantify spatial resolution for the Hi-Res and Hi-Res/HD scan modes. Using the proposed method, the modulation transfer functions (MTFs) of a 64-slice MDCT system (Discovery CT750 HD, GE Healthcare) equipped with both Hi-Res and Hi-Res/HD modes were measured using a metal bead at nine different off-centered positions (0-16 cm with a step size of 2 cm); at each position, both conventional scans and Hi-Res scans were performed. For each type of scan and position, 80 repeated acquisitions were performed to reduce noise induced uncertainties in the MTF measurements. A total of 15 reconstruction kernels, including eight conventional kernels and seven HD kernels, were used to reconstruct CT images of the bead. An ex vivo animal study consisting of a bone fracture model was performed to corroborate the MTF results, as the detection of this high-contrast and high frequency task is predominantly determined by spatial resolution. Images of this animal model generated by different scan modes and reconstruction kernels were qualitatively compared with the MTF results. At the centered position, the use of Hi-Res mode resulted in a slight improvement in the MTF; each HD kernel generated higher spatial resolution than its counterpart conventional kernel. However, the MTF along the

  7. Intraoral scan bodies in implant dentistry: A systematic review.

    Science.gov (United States)

    Mizumoto, Ryan M; Yilmaz, Burak

    2018-04-05

    Intraoral scan body (ISB) design is highly variable and its role in the digital workflow and accuracy of digital impressions is not well understood. The purpose of this systematic review was to determine the relevant reports pertaining to ISBs with regard to design and accuracy and to describe their evolution and role in the digital dentistry workflow. Special attention was placed on their key features in relation to intraoral scanning technology and the digitization process. A MEDLINE/PubMed search was performed to identify relevant reports pertaining to ISB usage in dentistry. This search included but was not limited to scan body features and design, scan body accuracy, and scan body techniques and the role of ISBs in computer-aided design and computer-aided manufacturing (CAD-CAM) processes. Commercially available scan bodies were examined, and a patient situation was shown highlighting the use of ISBs in the digital workflow. Deficiencies in the reports were found regarding various scan body topics, including ISB features/design, accuracy, and the role of ISBs in CAD-CAM processes. ISBs are complex implant-positioning-transfer devices that play an essential role in the digital workflow and fabrication of accurately fitting implant-supported restorations. With scanner technology rapidly evolving and becoming more widespread, future studies are needed and should be directed toward all parts of the digital workflow when using ISBs. By understanding the basic components of ISBs and how they relate to digital scanning and CAD-CAM technology, more emphasis may be placed on their importance and usage in the digital workflow to ensure accurate transfer of implant position to the virtual and analog definitive cast. Efforts should be made by clinicians to identify an optimal ISB design in relation to the specific intraoral scanning technology being used. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights

  8. Comparative study on skull CT scan and bone scintigraphy in chronic hemodialysed patients

    International Nuclear Information System (INIS)

    Ochi, Hironobu; Inoue, Yuichi; Fukuda, Teruo; Shibakiri, Ippei; Tsuda, Kazuyoshi

    1981-01-01

    A comparative study of computed tomography (XCT) scan utilizing EMI head unit and radionuclide bone scan was performed in 17 patients with chronic renal failure on maintenance hemodialysis. Bone scintigram was positive in 7 out of 17 patients. EMI number of the skull in the positive bone scintigram group was significantly lower than that of the negative bone scintigram. Radionuclide bone scan is the most useful method to detect early bone change and XCT scan will determine the grade of the bone mineral contents. XCT is especially useful to follow patients under the medical treatment (active vitamine D 3 therapy) in order to know the therapeutic effect. (author)

  9. Small nodule detectability evaluation using a generalized scan-statistic model

    International Nuclear Information System (INIS)

    Popescu, Lucretiu M; Lewitt, Robert M

    2006-01-01

    In this paper is investigated the use of the scan statistic for evaluating the detectability of small nodules in medical images. The scan-statistic method is often used in applications in which random fields must be searched for abnormal local features. Several results of the detection with localization theory are reviewed and a generalization is presented using the noise nodule distribution obtained by scanning arbitrary areas. One benefit of the noise nodule model is that it enables determination of the scan-statistic distribution by using only a few image samples in a way suitable both for simulation and experimental setups. Also, based on the noise nodule model, the case of multiple targets per image is addressed and an image abnormality test using the likelihood ratio and an alternative test using multiple decision thresholds are derived. The results obtained reveal that in the case of low contrast nodules or multiple nodules the usual test strategy based on a single decision threshold underperforms compared with the alternative tests. That is a consequence of the fact that not only the contrast or the size, but also the number of suspicious nodules is a clue indicating the image abnormality. In the case of the likelihood ratio test, the multiple clues are unified in a single decision variable. Other tests that process multiple clues differently do not necessarily produce a unique ROC curve, as shown in examples using a test involving two decision thresholds. We present examples with two-dimensional time-of-flight (TOF) and non-TOF PET image sets analysed using the scan statistic for different search areas, as well as the fixed position observer

  10. New scanning technique for the optical vortex microscope.

    Science.gov (United States)

    Augustyniak, Ireneusz; Popiołek-Masajada, Agnieszka; Masajada, Jan; Drobczyński, Sławomir

    2012-04-01

    In the optical vortex microscopy the focused Gaussian beam with optical vortex scans a sample. An optical vortex can be introduced into a laser beam with the use of a special optical element--a vortex lens. When moving the vortex lens, the optical vortex changes its position inside the spot formed by a focused laser beam. This effect can be used as a new precise scanning technique. In this paper, we study the optical vortex behavior at the sample plane. We also estimate if the new scanning technique results in observable effects that could be used for a phase object detection.

  11. PET scanning in plastic and reconstructive surgery

    International Nuclear Information System (INIS)

    Eirini, L.; Emmanouil, L.; Othonas, P.; Hans-Guenther, M.; Nikolaos, P.A.

    2012-01-01

    In this report we highlight the use of position emission tomography (PET) scan in plastic and reconstructive surgery. PET scanning is a very important tool in plastic surgery oncology (melanoma, soft-tissue sarcomas and bone sarcomas, head and neck cancer, peripheral nerve sheath tumors of the extremities and breast cancer after breast esthetic surgery), as diagnosis, staging, treatment planning and follow-up of cancer patients is based on imaging. PET scanning seems also to be useful as a flap monitoring system as well as an infection's imaging tool, for example in the management of diabetic foot ulcer. PET also contributes to the understanding of pathophysiology of keloids which remain a therapeutic challenge. (author)

  12. Construction of a four tip scanning tunneling microscope/scanning electron microscope combination and conductivity measurements of silicide nanowires

    International Nuclear Information System (INIS)

    Zubkov, Evgeniy

    2013-01-01

    In this work the combination of a four-tip scanning tunneling microscope with a scanning electron microscope is presented. By means of this apparatus it is possible to perform the conductivity measurements on the in-situ prepared nanostructures in ultra-high vacuum. With the aid of a scanning electron microscope (SEM), it becomes possible to position the tunneling tips of the four-tip scanning tunneling microscope (STM), so that an arrangement for a four-point probe measurement on nanostructures can be obtained. The STM head was built according to the novel coaxial Beetle concept. This concept allows on the one hand, a very compact arrangement of the components of the STM and on the other hand, the new-built STM head has a good mechanical stability, in order to achieve atomic resolution with all four STM units. The atomic resolution of the STM units was confirmed by scanning a Si(111)-7 x 7 surface. The thermal drift during the STM operation, as well as the resonant frequencies of the mechanical structure of the STM head, were determined. The scanning electron microscope allows the precise and safe navigation of the tunneling tips on the sample surface. Multi tip spectroscopy with up to four STM units can be performed synchronously. To demonstrate the capabilities of the new-built apparatus the conductivity measurements were carried out on metallic yttrium silicide nanowires. The nanowires were prepared by the in-situ deposition of yttrium on a heated Si(110) sample surface. Current-voltage curves were recorded on the nanowires and on the wetting layer in-between. The curves indicate an existence of the Schottky barrier between the yttrium silicide nanowires and the silicon bulk. By means of the two-tip measurements with a gate, the insulating property of the Schottky barrier has been confirmed. Using this Schottky barrier, it is possible to limit the current to the nanowire and to prevent it from flowing through the silicon bulk. A four-tip resistance measurement

  13. Correlation of Major Scan Findings and Esophageal Varices in Liver Cirrhosis

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, J S; Bahk, Y W; Lim, J L [Catholic University College of Medicine, Seoul (Korea, Republic of)

    1970-03-15

    In an endeavor to help understand some typical scan findings and portal hemodynamics in liver cirrhosis, several commonly occurring scan changes and esophageal varices as demonstrated by esophagram were correlated one another from quantitative and qualitative stand points. Clinical materials consisted of 34 patients with proven diagnosis of liver cirrhosis and esophageal varices. Liver scan was performed with colloidal 198-Au and the changes in the size and internal architecture of the Liver, splenic uptake and splenomegaly were graded and scored by repeated double-blind readings. The variceal changes on esophagrams were also graded according to the classification of Shanks and Kerley following modification. Of 34 patients, 91% showed definite reducing in liver volume(shrinkage) constituting the most frequent scan change. The splenic uptake and splenomegaly were noted in 73.5 and 79.4%, respectively. The present study revealed no positive correlation between the graded scan findings including shrinkage of the liver, splenic uptake or splenomegaly and severity of variceal changes of the esophagus. Exceptionally, however, apparently paradoxical correlation was noted between the severity of mottling and varices. Thus, in the majority(73.5%) of patients mottling were either absent or mild. This interesting observation is in favor of the view held by Christie et al. who consider the mottlings to be not faithful expression of actual scarring of the cirrhosis liver. This also would indicate that variceal changes are to be the results of intrahepatic arteriovenous shunting of blood with hypervolemic load to the portal system rather than simple hypertension secondary to fibrosis and shrinkage.

  14. Correlation of Major Scan Findings and Esophageal Varices in Liver Cirrhosis

    International Nuclear Information System (INIS)

    Ahn, J. S.; Bahk, Y. W.; Lim, J. L.

    1970-01-01

    In an endeavor to help understand some typical scan findings and portal hemodynamics in liver cirrhosis, several commonly occurring scan changes and esophageal varices as demonstrated by esophagram were correlated one another from quantitative and qualitative stand points. Clinical materials consisted of 34 patients with proven diagnosis of liver cirrhosis and esophageal varices. Liver scan was performed with colloidal 198-Au and the changes in the size and internal architecture of the Liver, splenic uptake and splenomegaly were graded and scored by repeated double-blind readings. The variceal changes on esophagrams were also graded according to the classification of Shanks and Kerley following modification. Of 34 patients, 91% showed definite reducing in liver volume(shrinkage) constituting the most frequent scan change. The splenic uptake and splenomegaly were noted in 73.5 and 79.4%, respectively. The present study revealed no positive correlation between the graded scan findings including shrinkage of the liver, splenic uptake or splenomegaly and severity of variceal changes of the esophagus. Exceptionally, however, apparently paradoxical correlation was noted between the severity of mottling and varices. Thus, in the majority(73.5%) of patients mottling were either absent or mild. This interesting observation is in favor of the view held by Christie et al. who consider the mottlings to be not faithful expression of actual scarring of the cirrhosis liver. This also would indicate that variceal changes are to be the results of intrahepatic arteriovenous shunting of blood with hypervolemic load to the portal system rather than simple hypertension secondary to fibrosis and shrinkage.

  15. Influence of heart rhythm, breathing and arm position during computed tomography scanning on the registration accuracy of electro anatomical map (EAM) images, left atrium three-dimensional computed tomography angiography images, and fluoroscopy time during ablation to treat atrial fibrillation

    International Nuclear Information System (INIS)

    Chono, Taiki; Shimoshige, Shinya; Yoshikawa, Kenta; Mizonobe, Kazuhusa; Ogura, Keishi

    2013-01-01

    In CARTOMERGE for treatment of atrial fibrillation (AF) by ablation, by integrating electro anatomical map (EAM) and left atrium three-dimensional computed tomography angiography (3D-CTA) images, identification of the ablation points is simplified and the procedure can be made carried out more rapidly. However, the influence that heart rhythm, breathing and arm position during CT scanning have on registration accuracy and fluoroscopy time is not clear. To clarify the influence on registration accuracy and fluoroscopy time of heart rhythm, breathing and arm position during CT scanning. The patients were CT-scanned during both sinus rhythm (SR) and AF in each study subject. We evaluated the registration accuracy of images reconstructed between the cardiac cycle and assessed the registration accuracy and fluoroscopy time of images obtained during inspiratory breath-hold, expiratory breath-hold and up and down position of the arm. Although the registration accuracy of the EAM image and left atrium 3D-CTA image showed a significant difference during SR, no significant difference was seen during AF. Expiratory breath-hold and down position of the arm resulted in the highest registration accuracy and the shortest fluoroscopy time. However, arm position had no significant effect on registration accuracy. Heart rhythm and breathing during CT scanning have a significant effect on the registration accuracy of EAM images, left atrium 3D-CTA images, and fluoroscopy time. (author)

  16. Contrast enhanced CT-scans are not comparable to non-enhanced scans in emphysema quantification

    International Nuclear Information System (INIS)

    Heussel, C.P.; Kappes, J.; Hantusch, R.; Hartlieb, S.; Weinheimer, O.; Kauczor, H.-U.; Eberhardt, R.

    2010-01-01

    Systemic, interventional and surgical treatments have gone new ways in treatment of emphysema. For longitudinal therapy monitoring and as end-points for clinical trials, quantification of the disease is necessary. Sensitive, easy to measure, as well as stable and reproducible parameters have to be characterized. One parameter that might affect emphysema quantification is IV contrast enhancement, which might also be indicated. Whether or not the contrast enhanced scan is also suited for emphysema quantification or an additional scan is necessary, a retrospective analysis of 12 adult patients undergoing clinically indicated both, a non-enhanced and enhanced thin section MSCT within a week (median 0 days, range 0-4 days) was done. The in-house YACTA software was used for automatic quantification of lung and emphysema volume, emphysema index, mean lung density, and 5th, 10th, 15th percentile. After IV contrast administration, the median CT derived lung volume decreased mild by 1.1%, while median emphysema volume decreased by relevant 11%. This results in a decrease of median emphysema index by 9%. The median lung density (15th percentile) increased after contrast application by 18 HU (9 HU). CT quantification delivers emphysema values that are clearly affected by IV contrast application. The detected changes after contrast application show the results of higher density in the lung parenchyma. Therefore the amount of quantified emphysema is reduced and the lung density increased after contrast enhancement. In longitudinal analyses, non-enhanced scans should be the reference, while enhanced scans cannot be used.

  17. Technetium 99mTc Pertechnetate Brain Scanning

    International Nuclear Information System (INIS)

    Rhee, Sang Min; Park, Jin Yung; Lee, Ahn Ki; Chung, Choo Il; Hong, Chang Gi; Rhee, Chong Heon; Koh, Chang Soon

    1968-01-01

    Technetium 99 mTc pertechnetate brain scanning were performed in 3 cases of head injury (2 chronic subdural hematomas and 1 acute epidural hematoma), 2 cases of brain abscess and 1 case of intracerebral hematoma associated with arteriovenous anomaly. In all the cases brain scintigrams showed 'hot areas.' Literatures on radioisotope scanning of intracranial lesions were briefly reviewed. With the improvement of radioisotope scanner and development of new radiopharmaceuticals brain scanning became a safe and useful screening test for diagnosis of intracranial lesions. Brain scanning can be easily performed even to a moribund patient without any discomfort and risk to the patient which are associated with cerebral angiography or pneumoencephalography. Brain scanning has been useful in diagnosis of brain tumor, brain abscess, subdural hematoma, and cerebral vascular diseases. In 80 to 90% of brain tumors positive scintigrams can be expected. Early studies were done with 203 Hg-Neohydrin or 131 I-serum albumin. With these agents, however, patients receive rather much radiation to the whole body and kidneys. In 1965 Harper introduced 99 mTc to reduce radiation dose to the patient and improve statistical variation in isotope scanning.

  18. /sup 67/Ga lung scan

    Energy Technology Data Exchange (ETDEWEB)

    Niden, A.H.; Mishkin, F.S.; Khurana, M.M.L.; Pick, R.

    1977-03-21

    Twenty-three patients with clinical signs of pulmonary embolic disease and lung infiltrates were studied to determine the value of gallium citrate /sup 67/Ga lung scan in differentiating embolic from inflammatory lung disease. In 11 patients without angiographically proved embolism, only seven had corresponding ventilation-perfusion defects compatible with inflammatory disease. In seven of these 11 patients, the /sup 67/Ga concentration indicated inflammatory disease. In the 12 patients with angiographically proved embolic disease, six had corresponding ventilation-perfusion defects compatible with inflammatory disease. None had an accumulation of /sup 67/Ga in the area of pulmonary infiltrate. Thus, ventilation-perfusion lung scans are of limited value when lung infiltrates are present. In contrast, the accumulation of /sup 67/Ga in the lung indicates an inflammatory process. Gallium imaging can help select those patients with lung infiltrates who need angiography.

  19. Method and apparatus for scanning x-ray tomography

    International Nuclear Information System (INIS)

    Albert, R.D.

    1988-01-01

    In a method of producing a tomographic image of a subject that includes the steps of generating X-rays at a moving origin point by directing a charged particle beam to a target surface, deflecting the charged particle beam to travel the origin point through a predetermined raster scan at the surface, detecting variations of X-ray intensity during the course of the raster scan at spaced apart detection points situated at the opposite side of the subject from the origin point, generating a first sequence of data values that is indicative of variations of X-ray intensity at a first of the detection points at successive times during the course of the raster scan and generating at least a second sequence of data values that is indicative of variations of X-ray intensity at a second of the detection points at successive times during the course of the same raster scan, the improvement is described comprising: combining successive individual data values of the first sequence that are generated by X-rays from successive particular locations in the raster scan with at least individual data values of the second sequence that are generated by X-rays from predetermined successive different locations in the same raster scan in order to produce a composite sequence of data values, and producing an image corresponding to at least a portion of the raster scan which depicts variations of the magnitude of successive data values of the composite sequence

  20. A generalized mean-squared displacement from inelastic fixed window scans of incoherent neutron scattering as a model-free indicator of anomalous diffusion confinement

    International Nuclear Information System (INIS)

    Roosen-Runge, F.; Seydel, T.

    2015-01-01

    Elastic fixed window scans of incoherent neutron scattering are an established and frequently employed method to study dynamical changes, usually over a broad temperature range or during a process such as a conformational change in the sample. In particular, the apparent mean-squared displacement can be extracted via a model-free analysis based on a solid physical interpretation as an effective amplitude of molecular motions. Here, we provide a new account of elastic and inelastic fixed window scans, defining a generalized mean-squared displacement for all fixed energy transfers. We show that this generalized mean-squared displacement in principle contains all information on the real mean-square displacement accessible in the instrumental time window. The derived formula provides a clear understanding of the effects of instrumental resolution on the apparent mean-squared displacement. Finally, we show that the generalized mean-square displacement can be used as a model-free indicator on confinement effects within the instrumental time window. (authors)

  1. Survey regarding the clinical practice of cardiac CT in Germany. Indications, scanning technique and reporting

    Energy Technology Data Exchange (ETDEWEB)

    Maurer, Marc H.; Hamm, B.; Dewey, M. [Inst. fuer Radiologie, Charite - Universitaetsmedizin Berlin (Germany)

    2009-12-15

    Purpose: to obtain an overview of the current clinical practice of cardiac computed tomography (CT) in Germany. Materials and methods: a 30-item question-naire was mailed to 149 providers of cardiac CT in Germany. The items asked about indications, scanning technique and reporting, data storage, and cost of the examination. Results: overall 45 questionnaires could be analyzed (30%). The majority of centers (76%, 34 of 45 centers) used CT scanners of the latest generation (at least 64 rows). The most common appropriate indications were exclusion of coronary artery disease (91%, 41/45), coronary anomalies (80%, 36/45), and follow-up after coronary artery bypass grafting (53%, 24/45). Each center examined on average 243 {+-} 310 patients in 2007 and the number of centers performing cardiac CT increased significantly in 2007 (p = 0.035) compared with the preceding year. Most used sublingual nitroglycerin (84%, 38/45; median of 2 sprays = 0.8 mg) and/or a beta blocker (86%, 39/44; median of 5 mg IV, median heart rate threshold: 70 beats/min). Many providers used ECG-triggered tube current modulation (65%, 29/44) and/or adjusted the tube current to the body mass index or body weight (63%, 28/44). A median slice thickness of 0.75 mm with a 0.5 mm increment and a 20 cm field-of-view was most commonly used. Source images in orthogonal planes (96%, 43/45), curved MPRs (93%, 42/45), and thin-slice MIPs (69%, 31/45) were used most frequently for interpretation. Extracardiac structures were also evaluated by 84% of the centers (38/45). The mean examination time was 16.2 min and reporting took an average of 28.8 min. (orig.)

  2. A False Positive {sup 18}F-FDG PET/CT Scan Caused by Breast Silicone Injection

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chao Jung; Lee, Bi Fang; Yao, Wei Jen; Wu, Pei Shan; Chen, Wen Chung; Peng, Shu Lin; Chiu, Nan Tsing [Cheng Kung University Medical College and Hospital, Tainan (Turkmenistan)

    2009-04-15

    We present here the case of a 40-year-old woman with a greater than 10 year prior history of bilateral breast silicone injection and saline bag implantation. Bilateral palpable breast nodules were observed, but the ultrasound scan was suboptimal and the magnetic resonance imaging showed no gadolinium enhanced tumor. The {sup 18}F-FDG PET/CT scan showed a hypermetabolic nodule in the left breast with a 30% increase of {sup 18}F-FDG uptake on the delayed imaging, and this mimicked breast cancer. She underwent a left partial mastectomy and the pathology demonstrated a siliconoma.

  3. Hepatobiliary scan in neonatal Jaundice

    International Nuclear Information System (INIS)

    Nahar, Nurun; Hasan, Mizanul; Karim, M.A.

    2002-01-01

    Jaundice is more or less common in newborn babies. Through physiological jaundice is most common cause of neonatal jaundice, possibility of obstructive jaundice especially biliary atresia should be kept in mind. Early diagnosis of biliary atresia followed by surgical treatment can save baby's life. Otherwise death is inevitable due to liver failure. Hepatobiliary scan is the imaging study of choice in neonatal jaundice especially when there is persistent conjugated hyperbilirubinaemia. Total 27 newborn babies of suspected biliary atresia, aged 14 days to 4 months were referred to Institute of Nuclear Medicine for Hepatobiliary scan. All of them had high serum bilirubin ranged from 6.0 mg/dl with an average of 9.35 ng/dl serum bilirubin level. Ultrasonography of hepatobiliary system was performed in 14 cases showing normal sized liver in 4 cases and hepatomegaly in 10 cases. Hepatobiliary scan was done with 99m Tc-Mebrofenin (Br IDA) after preparing the baby with phenobarbitone for 3-5 days. 20 (67%) cases were scan positive suggesting biliary atresia (BA) and 7(27%) cases were scan negative. In BA there will be increased hepatic uptake of the radionuclide without any significant excretion even in 24 hours delayed images. Presence of radiotracer in the bowel exclude the diagnosis of BA. Early diagnosis of biliary atresia is very important because in this condition surgery should be performed early (within 60 days of life). Studies suggest that hepatobiliary scan after hepatic stimulation with phenobarbitone for a period of 3-5 days is highly accurate for differentiating biliary atresia from other causes of neonatal jaundice. It is very important to perform hepatobiliary scan in a case of neonatal jaundice to exclude biliary atresia for the sake of baby's life.(author)

  4. Nondestructive evaluation of adhesive joints by C-scan ultrasonic testing

    International Nuclear Information System (INIS)

    Zeighami, Mehdi; Honarvar, Farhang

    2009-01-01

    Evaluation of the quality of adhesive bonding is an important issue in many industries who incorporate adhesive joints in their products. Over the past few decades, numerous acoustical techniques have been developed for nondestructive testing (NDT) of adhesively bonded joints. Among these techniques, the ultrasonic pulse-echo method is the most promising means for inspection of adhesive bonds. In practice, due to low impedance matching between adhesive and metal, the discrimination of a good bond from a bad bond is difficult. The low impedance matching also results in low contrast between perfect and disbanded zone in a C-scan image. In this paper, the quality of the interface between aluminum and epoxy is investigated by using an in-house built ultrasonic C-scan system. Two adhesion indices are proposed for producing C-scan images. To verify the capability of these indices, an adhesively bonded sample was fabricated using aluminum plates and epoxy. An artificial defect was implanted in the first interface of the specimens. The C-scan measurement prepared based on the proposed indices was able to reveal the defect much better than the C-scan image prepared by conventional approach. (author)

  5. Liver scanning in short interval autopsy material of cancer patients

    International Nuclear Information System (INIS)

    Appelqvist, P.; Salmo, M.; Kostiainen, S.

    1980-01-01

    The accuracy of liverscanning alkaline phosphatase and 5'-nucleotidase in the detection of the hepatic metastases was studied in short interval autopsy material of 243 cancer patients. The highest percentage of correct diagnosis was by 5'-nucleotidase, alkaline phosphatase was the second, and scanning third. The overall accuracy of liver scan was 68 per cent. It was the better the shorter the time interval between scanning and autopsy. The higher percentage of incorrect diagnoses of the scan was related to a larger number of false positives, the causes of which were to be verified only in half of the cases. (orig.) [de

  6. Biochemical aspects of the neoplastic cell in relation to positive indicators

    International Nuclear Information System (INIS)

    Strom, R.

    1975-01-01

    In scintigraphic diagnoses with positive indicators, the capacity of these indicators to fix themselves or to selectively concentrate in the neoplastic tissue is utilized. This selectivity could be due to several biochemical peculiarities of the tumor cells in relation to surrounding cells: the presence on the membrane of particular chemical groups which allow these cells to invade adjacent tissue without being subject to contact inhibition; the presence on these same membranes of antigenic determinants which are particular to these cells and which can be revealed with specific antibodies; a high concentration of nucleic acid in tumor cells, with the associated possibility of fixing substances having a particular tropism for nucleic acids or for their chemical constituents; an elevated rate of nucleic acid synthesis, with an associated increase in the incorporation of precursors and also of substances which specifically interfere with this biochemical pathway; in numerous cases, tumor cells produce high quantities of acidic metabolites which must be neutralized by equivalent quantities of anions, the latter entering the cells by active transport phenomena; in tumors which develop particularly rapidly, there is a development of degenerative processes with an accumulation of degradation products; in metastatic tumors, the cells have metabolic and biosynthetic activities which are a function of the original tissue, with the possiblity of a clear metabolic difference in relation to adjacent tissues [fr

  7. Improving diagnosis of acute appendicitis with atypical findings by Tc-99m HMPAO leukocyte scan

    International Nuclear Information System (INIS)

    Shung-Shung, S.; Kao, A.; Mei-Due, Y.; Hwei-Chung, W.

    2002-01-01

    Aim: Even with careful observation, the overall false-positive rate of laparotomy remains 10-15% when acute appendicitis was suspected. Therefore, the clinical efficacy of Tc-99m HMPAO labeled leukocyte (TC-WBC) scan for the diagnosis of acute appendicitis in patients presenting with atypical clinical findings is assessed. Patients and Methods: Eighty patients presenting with acute abdominal pain and possible acute appendicitis but atypical findings were included in this study. After intravenous injection of TC-WBC, serial anterior abdominal/pelvic images at 30, 60, 120 and 240 min with 800 k counts were obtained with a gamma camera. Any abnormal localization of radioactivity in the right lower quadrant of the abdomen, equal to or greater than bone marrow activity, was considered as a positive scan. Results: 36 out of 49 patients showing positive TC-WBC scans received appendectomy. They all proved to have positive pathological findings. Five positive TC-WBC were not related to acute appendicitis, because of other pathological lesions. Eight patients were not operated and clinical follow-up after one month revealed no acute abdominal condition. Three of 31 patients with negative TC-WBC scans received appendectomy. They also presented positive pathological findings. The remaining 28 patients did not receive operations and revealed no evidence of appendicitis after at least one month of follow-up. The overall sensitivity, specificity, accuracy, positive and negative predictive values for TC-WBC scan to diagnose acute appendicitis were 92, 78, 86, 82, and 90%, respectively. Conclusion: TC-WBC scan provides a rapid and highly accurate method for the diagnosis of acute appendicitis in patients with equivocal clinical examination. It proved useful in reducing the false-positive rate of laparotomy and shortens the time necessary for clinical observation. (orig.)

  8. The role of FDG-PET/CT in preoperative staging of sentinel lymph node biopsy-positive melanoma patients

    DEFF Research Database (Denmark)

    Frary, Charles; Gad, Dorte; Bastholt, Lars

    2016-01-01

    or uncover anything else of relevance. FDG-PET/CT did, however, provide false positive findings in 13 % (6/46) of these patients. These scans triggered additional, predominantly invasive, procedures, which did not ultimately have an impact on the therapeutic strategy. Thus, these findings indicate a need...

  9. The comparing results of carcinoma between three-phase and delayed whole body bone scan

    International Nuclear Information System (INIS)

    Si Hongwei; Li Xianfeng

    2004-01-01

    Purpose: Three phase bone scan is an imaging technology in nuclear medicine, which composed of blood flow phase, blood pool phase and delayed phase and the last one is often performed in routine works in department of nuclear medicine. The purpose of this study is to evaluate the merit of three-phase bone scan.Methods: In this study, we chose 54 patients who were having an regional pain which caused by benign or malignant carcinoma that diagnosed by CT, X-ray, ECT, MRI or other examinations. The imaging were acquired simultaneously from both anterior and posterior views, after a bolus injection of 1110 MBq technetium-99m-labelled methylene diphosphonate (MDP), blood phase contains 20 frame sand 3 seconds per frame, blood pool phase contains 5 frames and 1 minute per frame, delayed phase was performed 2.5 hour later. According to the results of three-phase bone scan, the patients were divided into 2 groups: normal and abnormal groups. The abnormal group includes early phase positive,delay positive and all three phase positive sets. The comparing among the 3 sets were analyzed by chi-square test and other statistic means.Results: There were 54 patients who had suffered lung cancer, breast cancer and other cancer,involved in this study, 34 males and 20 females, ranged age 17 to 88 years, were normal in 15 cases,positive in 22 cases, the results in delayed phase were positive in 9 cases, blood flow and blood pool phase showed blood flow changes in 4 cases and soft tissue tumors were seen in 4 cases. Three phase bone scan was more sensitive than delayed whole body bone scan in detecting the abnormal sites (p 0.05) The sensitivity of detecting tumors in blood flow and blood pool phase,delayed phase were respectively lower than in three phase bone scan (p<0.001).Conclusion: It is more sensitivity of detecting tumor lesions in three phase bone scan than in delayed phase whole body bone scan and the changes of blood flow and soft tissue can be seen in three phase bone scan

  10. Multiphoton minimal inertia scanning for fast acquisition of neural activity signals

    Science.gov (United States)

    Schuck, Renaud; Go, Mary Ann; Garasto, Stefania; Reynolds, Stephanie; Dragotti, Pier Luigi; Schultz, Simon R.

    2018-04-01

    Objective. Multi-photon laser scanning microscopy provides a powerful tool for monitoring the spatiotemporal dynamics of neural circuit activity. It is, however, intrinsically a point scanning technique. Standard raster scanning enables imaging at subcellular resolution; however, acquisition rates are limited by the size of the field of view to be scanned. Recently developed scanning strategies such as travelling salesman scanning (TSS) have been developed to maximize cellular sampling rate by scanning only select regions in the field of view corresponding to locations of interest such as somata. However, such strategies are not optimized for the mechanical properties of galvanometric scanners. We thus aimed to develop a new scanning algorithm which produces minimal inertia trajectories, and compare its performance with existing scanning algorithms. Approach. We describe here the adaptive spiral scanning (SSA) algorithm, which fits a set of near-circular trajectories to the cellular distribution to avoid inertial drifts of galvanometer position. We compare its performance to raster scanning and TSS in terms of cellular sampling frequency and signal-to-noise ratio (SNR). Main Results. Using surrogate neuron spatial position data, we show that SSA acquisition rates are an order of magnitude higher than those for raster scanning and generally exceed those achieved by TSS for neural densities comparable with those found in the cortex. We show that this result also holds true for in vitro hippocampal mouse brain slices bath loaded with the synthetic calcium dye Cal-520 AM. The ability of TSS to ‘park’ the laser on each neuron along the scanning trajectory, however, enables higher SNR than SSA when all targets are precisely scanned. Raster scanning has the highest SNR but at a substantial cost in number of cells scanned. To understand the impact of sampling rate and SNR on functional calcium imaging, we used the Cramér-Rao Bound on evoked calcium traces recorded

  11. 67Ga scanning and upper gastrointestinal series for gastric lymphomas

    International Nuclear Information System (INIS)

    Ichiya, Y.; Oshiumi, Y.; Kamoi, I.; Imoto, T.; Shimoda, Y.; Kitagawa, S.; Matsuura, K.

    1982-01-01

    67 Ga scanning and upper gastrointestinal (UGI) series were performed in 13 patients with gastric lymphomas before any treatment was initiated. Seven of these patients also underwent both examinations after completing chemotherapy and/or radiation therapy. Prior to treatment, all 13 patients had abnormalities on the UGI examination, and 12 of them had abnormalities on the 67 Ga scans. In 6 patients, more extensive gastric abnormalities were demonstrated by 67 Ga scanning than by UGI examination. Although persistent 67 Ga uptake after treatment was indicative of relatively poor therapeutic response, lack of uptake did not always indicate a good response to treatment

  12. Social position and health in old age. The relevance of different indicators of social position

    DEFF Research Database (Denmark)

    Avlund, Kirsten; Holstein, Bjørn Evald; Osler, Merete

    2002-01-01

    Social medicine, social position, chronic diseases, material wealth, income, tenure, oral health, functional ability, well-being, mobility......Social medicine, social position, chronic diseases, material wealth, income, tenure, oral health, functional ability, well-being, mobility...

  13. Detection of Arthritis by Joint Scanning

    Energy Technology Data Exchange (ETDEWEB)

    Maxfield, W. S. [Dept, of Radiology, Louisiana State University School of Medicine, New Orleans, LA (United States); Weiss, T. E.; Tutton, R. H.; Hidalgo, J. U. [Ochsner Clinic and Ochsner Foundation Hospital, New Orleans, LA (United States)

    1969-05-15

    Detection and identification of early arthritis is frequently difficult with routine methods. Several tracers, {sup 131}I human serum albumin (25 {mu}Ci/10 lb), {sup 99m}Tc human serum albumin (1-3 mCi), {sup 131}I iodipamide (40 {mu}Ci/10 lb), and {sup 99m}Tc pertechnetate (10 mCi), have been employed for joint scanning to detect synovitis produced by arthritis in joints of the extremities. When administered intravenously, the 25% increase in localization of these tracers in the synovial membrane, if there is active synovitis, can be demonstrated by scintillation scanning. This ability to detect synovitis at an early stage enables the joint scan to show areas of active synovitis not demonstrated on roentgenograms. The scan may objectively confirm or disprove questionable physical findings. From this standpoint the technique has been useful in determining whether joint pain is functional or due to arthritis as a negative localization tends to rule out active synovitis as the cause of the pain. The scan demonstration of a positive localization of the tracer in several joints when only one area is symptomatic is evidence that joint pain is due to systemic disease. The short half-life tracera permit serial studies to follow the course of an arthritis process. Use of {sup 99m}Tc pertechnetate and an Anger camera have made joint scanning a practical technique for clinical use. A review of the accuracy of joint scanning in 130 cases as compared to roentgenograms is presented. (author)

  14. Positive Result by Serology Indicates Active Helicobacter pylori Infection in Patients with Atrophic Gastritis

    OpenAIRE

    Kokkola, Arto; Rautelin, Hilpi; Puolakkainen, Pauli; Sipponen, Pentti; Färkkilä, Martti; Haapiainen, Reijo; Kosunen, Timo U.

    1998-01-01

    Patients with atrophic corpus gastritis and elevated Helicobacter pylori antibody titers but 13C-urea breath test (13C-UBT) and histology results negative for H. pylori were randomized into eradication therapy or follow-up only. Antibody levels decreased significantly in six out of seven patients in the eradication group, while in the follow-up group, the titers declined in only one out of eight patients. In patients with atrophic corpus gastritis, positive serology results may indicate an on...

  15. Significance of calcific valvular heart disease in /sup 99m/Tc pyrophosphate myocardial infarction scanning: radiographic, scintigraphic, and pathological correlation

    International Nuclear Information System (INIS)

    Jengo, J.A.; Mena, I.; Joe, S.H.; Criley, J.M.

    1977-01-01

    Technetium-99m pyrophosphate (PP/sub i/) is currently considered the best scanning agent for the diagnosis of acute myocardial infarction. False-positive scans have been reported in association with unstable angina, alcoholic cardiomyopathy, and ventricular aneurysms. In this study, 86 percent of patients (12/14) with either calcific aortic or mitral valvular heart disease had positive PP/sub i/ cardiac scintiscans and the location of the PP/sub i/ uptake was limited to the calcific valve in all (9/9) of the patients who underwent valve replacement surgery. Six patients with valvular disease without radiologic evidence of calcium had negative PP/sub i/ heart images. Three of these patients had surgical valve replacement, and in none was there increased uptake in the resected valve. Seventy-five percent of the patients with calcified aortic valves had localization of the PP/sub i/ activity to the area of the aortic valve, whereas 50 percent of the patients with calcified mitral valves showed a diffuse pattern of uptake on the cardiac image. In vitro demonstration of increased radioactivity in surgically removed cardiac valves warrants the conclusion that Tc-99m PP/sub i/ is taken up by calcified heart valves. We conclude that while PP/sub i/ heart scanning is a sensitive indicator of acute myocardial infarction, false-positive scans can occur in the presence of calcific valvular disease, due to localization of PP/sub i/ in the calcified portion of the valve

  16. Significance of calcific valvular heart disease in /sup 99m/Tc pyrophosphate myocardial infarction scanning: radiographic, scintigraphic, and pathological correlation

    Energy Technology Data Exchange (ETDEWEB)

    Jengo, J.A.; Mena, I.; Joe, S.H.; Criley, J.M.

    1977-08-01

    Technetium-99m pyrophosphate (PP/sub i/) is currently considered the best scanning agent for the diagnosis of acute myocardial infarction. False-positive scans have been reported in association with unstable angina, alcoholic cardiomyopathy, and ventricular aneurysms. In this study, 86 percent of patients (12/14) with either calcific aortic or mitral valvular heart disease had positive PP/sub i/ cardiac scintiscans and the location of the PP/sub i/ uptake was limited to the calcific valve in all (9/9) of the patients who underwent valve replacement surgery. Six patients with valvular disease without radiologic evidence of calcium had negative PP/sub i/ heart images. Three of these patients had surgical valve replacement, and in none was there increased uptake in the resected valve. Seventy-five percent of the patients with calcified aortic valves had localization of the PP/sub i/ activity to the area of the aortic valve, whereas 50 percent of the patients with calcified mitral valves showed a diffuse pattern of uptake on the cardiac image. In vitro demonstration of increased radioactivity in surgically removed cardiac valves warrants the conclusion that Tc-99m PP/sub i/ is taken up by calcified heart valves. We conclude that while PP/sub i/ heart scanning is a sensitive indicator of acute myocardial infarction, false-positive scans can occur in the presence of calcific valvular disease, due to localization of PP/sub i/ in the calcified portion of the valve.

  17. High positive computed tomography yields in the emergency ...

    African Journals Online (AJOL)

    when the diagnosis is uncertain.[1,2] It is therefore ... Methods. This was a retrospective record review of all patients who received CT ... period. Primary outcomes were to establish CT scan usage and positive yield rates. ... scans performed in the hospital. ... considered for surgical intervention may have a negative scan and.

  18. Localisation of malignant germ-cell tumours by external scanning after injection of radiolabelled anti-alpha-fetoprotein

    International Nuclear Information System (INIS)

    Halsall, A.K.; Fairweather, D.S.; Bradwell, A.R.; Blackburn, J.C.; Howell, A.; Dykes, P.W.; Reeder, A.; Hine, K.R.

    1981-01-01

    Sheep IgG antibody to alpha-fetoprotein was labelled with 131 I and used to identify human germ-cell tumours by emission scanning. Eleven patients were studied after resection of their primary tumours. Ten had malignant teratoma and one an endodermal sinus tumour. All eight patients with raised serum alpha-fetoprotein concentrations had metastases apparent in the antibody scans. Of the remaining three patients with normal serum alpha-fetoprotein concentrations, two had positive scans. Three of the patients with positive results were scanned twice; the second scans were negative after treatment, when the alpha-fetoprotein concentrations had returned to normal. These results suggest that antibody scans are useful in the clinical management of patients with germ-cell tumours. (author)

  19. Quantitative measurement of ventricular dilatation on CT scan

    International Nuclear Information System (INIS)

    Okita, Naoshi; Mochizuki, Hiroshi; Takase, Sadao

    1985-01-01

    Cerebral atrophy might be judged from the ventricular dilatation with some indices, calculated from various ventricular width. But, there is no general agreement on what index is the most reliable. In this paper, we attempted to establish the index, easy to measure and most reliable. Our method is as follow. 1) We carried out the CT scan (EMI 1010) on 89 neurologically intact patients. Scans were parallel to orbito-meatal line (OML), and were 10 mm in thickness. On CT scan films, various width, area of anterior horns and area of bodies of lateral ventricles were measured. Measurement about the anterior horns of lateral ventricles were carried out on image the most clearly showed the foramen of Monro. And measurements about the bodies of lateral ventricles were on image, 20 mm above the image of anterior horn. Correlations of various width and areas were calculated. Then we proposed new indices with high correlations (over 0.9) with ventricular area; Anterior horn CVI (Cerebro-Ventricular Index) and Body CVI. 2) Patients with myotonic dystrophy show cerebral atrophy. We carried out the CT scan (GECT/T 8800) on 17 myotonic dystrophy patients and 30 controls. Between the two groups, age and sex were almost matched. In the two groups, we calculated our new indices as well as various indices which have been reported; Huckman number, Bifrontal CVI, Bicaudal CVI, Anterior horn index, Hirajima's index, and Cella-media index. The data were analyzed statistically. The ventricular dilatation of myotonic dystrophy patients is more definite with Anterior horn CVI, Bicaudal CVI and Body CVI (p<0.01). These indices have higher correlations with the ventricular area (about 0.9). (J.P.N.)

  20. Bone position emission tomography with or without CT Is more accurate than bone scan for detection of bone metastasis

    International Nuclear Information System (INIS)

    Lee, Soo Jin; Lee, Wom Woo; Kim, Sang Eun

    2013-01-01

    Na1 8F bone positron emission tomography (bone PET) is a new imaging modality which is useful for the evaluation of bone diseases. Here, we compared the diagnostic accuracies between bone PET and bone scan for the detection of bone metastasis (BM). Sixteen cancer patients (M:F = 10:6, mean age = 60 ± 12 years) who underwent both bone PET and bone scan were analyzed. Bone PET was conducted 30 minutes after the injection of 370 MBq Na1 8F , and a bone scan was performed 3 hours after the injection of 1295 MBq 9 9mT c-hydroxymethylene diphosphonate. In the patient-based analysis (8 patients with BM and 8 without BM), the sensitivities of bone PET (100% 8/8) and bone scan (87.5% = 7/8) were not significantly different (p > 0.05), whereas the specificity of bone PET (87.5% = 7/8) was significantly greater than that of the bone scan (25% = 2/8) (p 8F bone PET is more accurate than bone scan for BM evaluation.

  1. CS-Studio Scan System Parallelization

    Energy Technology Data Exchange (ETDEWEB)

    Kasemir, Kay [ORNL; Pearson, Matthew R [ORNL

    2015-01-01

    For several years, the Control System Studio (CS-Studio) Scan System has successfully automated the operation of beam lines at the Oak Ridge National Laboratory (ORNL) High Flux Isotope Reactor (HFIR) and Spallation Neutron Source (SNS). As it is applied to additional beam lines, we need to support simultaneous adjustments of temperatures or motor positions. While this can be implemented via virtual motors or similar logic inside the Experimental Physics and Industrial Control System (EPICS) Input/Output Controllers (IOCs), doing so requires a priori knowledge of experimenters requirements. By adding support for the parallel control of multiple process variables (PVs) to the Scan System, we can better support ad hoc automation of experiments that benefit from such simultaneous PV adjustments.

  2. [Social self-positioning as indicator of socioeconomic status].

    Science.gov (United States)

    Fernández, E; Alonso, R M; Quer, A; Borrell, C; Benach, J; Alonso, J; Gómez, G

    2000-01-01

    Self-perceived class results from directly questioning subjects about his or her social class. The aim of this investigation was to analyse self-perceived class in relation to other indicator variables of socioeconomic level. Data from the 1994 Catalan Health Interview Survey, a cross-sectional survey of a representative sample of the non-institutionalised population of Catalonia was used. We conducted a discriminant analysis to compute the degree of right classification when different socioeconomic variables potentially related to self-perceived class were considered. All subjects who directly answered the questionnaire were included (N = 12,245). With the aim of obtaining the discriminant functions in a group of subjects and to validate it in another one, the subjects were divided into two random samples, containing approximately 75% and 25% of subjects (analysis sample, n = 9,248; and validation sample, n = 2,997). The final function for men and women included level of education, social class (based in occupation) and equivalent income. This function correctly classified 40.9% of the subjects in the analysis sample and 39.2% in the validation sample. Two other functions were selected for men and women separately. In men, the function included level of education, professional category, and family income (39.2% of classification in analysis sample and 37.2% in validation sample). In women, the function (level of education, working status, and equivalent income) correctly classified 40.3% of women in analysis sample whereas the percentage was 38.9% in validation sample. The percentages of right classification were higher for the highest and lowest classes. These results show the utility of a simple variable to self-position within the social scale. Self-perceived class is related to education, income, and working determinants.

  3. Bone scanning in Shin Splint evaluation

    International Nuclear Information System (INIS)

    Dumont, M.; Lamoureux, F.; Lamoureux, J.; Danais, S.; Lacoste, P.; Duranceau, J.

    1983-01-01

    Jogging is increasingly popular; in U.S.A., in 1979 more than 25 millions people were considered joggers. Lesions of the locomotive system of the lower limbs are very frequent in athletes and the Shin Splint syndrome, for one, is very frequent. However this precise clinical entity, usually X-Ray negative, is ill-known. A bone scan study in a series of 30 athletes suffering from Shin Splints is presented. The bone scans being positive and typical were highly useful in confirming the clinical diagnosis. Moreover, follow-up studies were done in a number of these patients and results correlated well with the clinical evolution [fr

  4. Clinical significance of segmental parenchymal excretion delay on Tc-99m DISIDA hepatobiliary scan

    International Nuclear Information System (INIS)

    Kang, D. Y.; Ryu, J. S.; Moon, D. H.; Lee, S. K.; Kim, M. H.; Lee, H. K.

    1998-01-01

    Segmental parenchymal excretion delay on Tc-99m DISIDA scan in caused by intrahepatic bile duct obstruction. However, the diagnostic value for intrahepatic bile duct obstruction is unknown. We conducted this study to assess the positive predictive value of segmental excretion delay for the diagnosis of intrahepatic bile duct obstruction, and additional benefit over other noninvasive radiologic studies. The study population consisted of 43 patients (48 scans) who showed segmental parenchymal excretion delay on Tc-99m DISIDA scan. The results of abdominal CT or ultrasonography, which was done within 1 month of Tc-99m DISIDA scan, were compared with scintigraphic findings. The etiology of segmental parenchymal excretion delay was determined by ERC or PTC in 31 scans, and follow-up studies in 13 scans. No causes were identified in 4 scans. The positive predictive value of segmental parenchymal excretion delay for intrahepatic bile duct obstruction was 92% (44/48). On the other hand, 13% (5/38) of CT and 28% (5/18) of ultrasonography were normal. In 18% *7/38) of CT and 17% (3/18) of ultrasonography, only intrahepatic bile duct dilatation was noted without any diagnostic findings of intrahepatic bile duct obstruction. Segmental parenchymal excretion delay on Tc-99m DISIDA scan had a high positive predictive value for the diagnosis of intrahepatic bile duct obstruction. Tc-99m DISIDA scan may be useful for the diagnosis of intrahepatic bile duct obstruction, especially in patients with nondiagnostic CT or ultrasonography. The diagnostic usefulness need to be confirmed by further prospective studies

  5. CT MEASUREMENTS OF TWO CEREBROVENTRICULAR INDICES AND THEIR RELATION WITH AGE

    Directory of Open Access Journals (Sweden)

    Ambili Puthanveettil

    2017-01-01

    Full Text Available BACKGROUND Cerebroventricular Indices are the relative measurements of the size of lateral ventricle to that of brain. A normal study of these indices are necessary in order to understand any changes in size of the ventricles or other associated abnormalities of the brain. The study uses measurements from Computerised Tomography (CT which is uniformly calibrated, has reproducible data and is less expensive than MRI. MATERIALS AND METHODS CT scans of 186 apparently healthy normal individuals of age group 1 to 85 years were taken and the subjects were categorized into age intervals of 10 years; males and females taken separately. The linear measurements of lateral ventricle and brain were taken directly from the screen. The cerebrovascular indices were calculated. The mean values in each group were compared with age and sex, using appropriate statistical tests. RESULTS Mean value for Bifrontal index was 0.31±0.03 and that of Bicaudate index was 0.12±0.02. Both indices showed a positive correlation with age. The relative size of the lateral ventricle with the brain did not show any gender difference. CONCLUSION The study results coincide with previous similar studies. Both the indices showed positive correlation with age, of which the Bicaudate index was more sensitive.

  6. Comparison of reliability of five patellar position indices at various stifle joint angles in pelvic limbs obtained from cadavers of red foxes (Vulpes vulpes)

    DEFF Research Database (Denmark)

    Miles, James E; Nielsen, Dorte H; Jensen, Bente Rona

    2012-01-01

    To compare 5 patellar position indices at various stifle joint angles in cadavers of red foxes, determine measurement reliability, and assess the suitability of these indices for clinical use.......To compare 5 patellar position indices at various stifle joint angles in cadavers of red foxes, determine measurement reliability, and assess the suitability of these indices for clinical use....

  7. Scanning laser microscope for imaging nanostructured superconductors

    International Nuclear Information System (INIS)

    Ishida, Takekazu; Arai, Kohei; Akita, Yukio; Miyanari, Mitsunori; Minami, Yusuke; Yotsuya, Tsutomu; Kato, Masaru; Satoh, Kazuo; Uno, Mayumi; Shimakage, Hisashi; Miki, Shigehito; Wang, Zhen

    2010-01-01

    The nanofabrication of superconductors yields various interesting features in superconducting properties. A variety of different imaging techniques have been developed for probing the local superconducting profiles. A scanning pulsed laser microscope has been developed by the combination of the XYZ piezo-driven stages and an optical fiber with an aspheric focusing lens. The scanning laser microscope is used to understand the position-dependent properties of a superconducting MgB 2 stripline of length 100 μm and width of 3 μm under constant bias current. Our results show that the superconducting stripline can clearly be seen in the contour image of the scanning laser microscope on the signal voltage. It is suggested from the observed image that the inhomogeneity is relevant in specifying the operating conditions such as detection efficiency of the sensor.

  8. Scanning laser microscope for imaging nanostructured superconductors

    Science.gov (United States)

    Ishida, Takekazu; Arai, Kohei; Akita, Yukio; Miyanari, Mitsunori; Minami, Yusuke; Yotsuya, Tsutomu; Kato, Masaru; Satoh, Kazuo; Uno, Mayumi; Shimakage, Hisashi; Miki, Shigehito; Wang, Zhen

    2010-10-01

    The nanofabrication of superconductors yields various interesting features in superconducting properties. A variety of different imaging techniques have been developed for probing the local superconducting profiles. A scanning pulsed laser microscope has been developed by the combination of the XYZ piezo-driven stages and an optical fiber with an aspheric focusing lens. The scanning laser microscope is used to understand the position-dependent properties of a superconducting MgB 2 stripline of length 100 μm and width of 3 μm under constant bias current. Our results show that the superconducting stripline can clearly be seen in the contour image of the scanning laser microscope on the signal voltage. It is suggested from the observed image that the inhomogeneity is relevant in specifying the operating conditions such as detection efficiency of the sensor.

  9. Assessment of the accuracy of AortaScan for detection of abdominal aortic aneurysm (AAA).

    Science.gov (United States)

    Abbas, A; Smith, A; Cecelja, M; Waltham, M

    2012-02-01

    AortaScan AMI 9700 is a portable 3D ultrasound device that automatically measures the maximum diameter of the abdominal aorta without the need for a trained sonographer. It is designed to rapidly diagnose or exclude an AAA and may have particular use in screening programs. Our objective was to determine its accuracy to detect AAA. Subjects from our AAA screening and surveillance programs were examined. The aorta was scanned using the AortaScan and computed tomography (CT). Ninety-one subjects underwent imaging (44 AAA on conventional ultrasound surveillance and 47 controls). The largest measurement obtained by AortaScan was compared against the CT-aortic measurement. The mean aortic diameter was 2.8 cm. The CT scan confirmed the diagnosis of AAA in 43 subjects. There was one false positive measurement on conventional ultrasound. AortaScan missed the diagnosis of AAA in eight subjects. There were thirteen false positive measurements. The sensitivity, specificity, positive and negative predictive values were 81%, 72%, 72% and 81% respectively. A device to detect AAA without the need for a trained operator would have potential in a community-based screening programme. The AortaScan, however, lacks adequate sensitivity and significant technical improvement is necessary before it could be considered a replacement for trained screening personnel. Copyright © 2011 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  10. Technetium {sup 99m}Tc Pertechnetate Brain Scanning

    Energy Technology Data Exchange (ETDEWEB)

    Rhee, Sang Min; Park, Jin Yung; Lee, Ahn Ki; Chung, Choo Il; Hong, Chang Gi [Capital Army Hospital, ROKA, Seoul (Korea, Republic of); Rhee, Chong Heon; Koh, Chang Soon [Radiological Research Institute, Seoul (Korea, Republic of)

    1968-03-15

    Technetium {sup 99}mTc pertechnetate brain scanning were performed in 3 cases of head injury (2 chronic subdural hematomas and 1 acute epidural hematoma), 2 cases of brain abscess and 1 case of intracerebral hematoma associated with arteriovenous anomaly. In all the cases brain scintigrams showed 'hot areas.' Literatures on radioisotope scanning of intracranial lesions were briefly reviewed. With the improvement of radioisotope scanner and development of new radiopharmaceuticals brain scanning became a safe and useful screening test for diagnosis of intracranial lesions. Brain scanning can be easily performed even to a moribund patient without any discomfort and risk to the patient which are associated with cerebral angiography or pneumoencephalography. Brain scanning has been useful in diagnosis of brain tumor, brain abscess, subdural hematoma, and cerebral vascular diseases. In 80 to 90% of brain tumors positive scintigrams can be expected. Early studies were done with 203 Hg-Neohydrin or {sup 131}I-serum albumin. With these agents, however, patients receive rather much radiation to the whole body and kidneys. In 1965 Harper introduced {sup 99}mTc to reduce radiation dose to the patient and improve statistical variation in isotope scanning.

  11. Reappraisal of radionuclide liver scans for preoperative gastric cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, Makoto; Yonahara, Yoshio; Yamashita, Shoji; Ando, Yutaka; Mohri, Makoto [National Second Hospital of Tokyo (Japan)

    1983-04-01

    Radionuclide liver scans were obtained in 89 preoperative patients with gastric cancer. Eight showed definite defects on liver scans. At laparotomy, 14 patients were found to have liver involvement secondary to gastric cancer. The sensitivity of liver scans to predict liver involvement is 57% (8/14), and the specificity is 100% (75/75). The patients with definite defects on liver scans had a lower rate of palliative resection of the primary tumors (2/8) than the patients with liver involvement and no scan abnormality (4/6). The patients with advanced lesions but without liver involvement had the highest probability of resecting the primary tumors (57/63 : 47 radical, and 10 palliative). Normal serum levels of liver chemistries did not preclude the presence of defects on liver scans. Additional three patients were found to have cirrhosis of the liver solely based on liver scans, which was confirmed at laparotomy. Radionuclide liver scans can predict liver involvement with very few false positives, and may discriminate patients unsuitable for laparotomy even with palliative intent.

  12. SU-E-J-220: Assessment of MRI Geometric Distortion in Head and Neck Cancer Patients Scanned in Immobilized Radiation Treatment Position

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, C; Mohamed, A; Weygand, J; Ding, Y; Fuller, C; Frank, S; Wang, J [MD Anderson Cancer Center, Houston, TX (United States)

    2015-06-15

    Purpose: Uncertainties about geometric distortion have somewhat hindered MRI simulation in radiation therapy. Most of the geometric distortion studies were performed with phantom measurements but another major aspect of MR distortion is patient related. We studied the geometric distortion in patient images by comparing their MRI scans with the corresponding CT, using CT as the non-distorted gold standard. Methods: Ten H&N cancer patients were imaged with MRI as part of a prospective IRB approved study. All patients had their treatment planning CT done on the same day or within one week of the MRI. MR Images were acquired with a T2 SE sequence (1×1×2.5mm voxel size) in the same immobilization position as in the CT scans. MRI to CT rigid registration was then done and geometric distortion comparison was done by measuring the corresponding anatomical landmarks on both the MRI and the CT images by two observers. Several skin to skin (9 landmarks), bone to bone (8 landmarks), and soft tissue (3 landmarks) were measured at specific levels in horizontal and vertical planes of both scans. Results: The mean distortion for all landmark measurements in all scans was 1.8±1.9mm. For each patient 11 measurements were done in the horizontal plane while 9 were done in the vertical plane. The measured geometric distortion were significantly lower in the horizontal axis compared to the vertical axis (1.3±0.16 mm vs 2.2±0.19 mm, respectively, P=0.003*). The magnitude of distortion was lower in the bone to bone landmarks compared to the combined soft tissue and skin to skin landmarks (1.2±0.19 mm vs 2.3±0.17 mm, P=0.0006*). The mean distortion measured by observer one was not significantly different compared toobserver 2 (2.3 vs 2.4 mm, P=0.4). Conclusion: MRI geometric distortions were quantified in H&N patients with mean error of less than 2 mm. JW received a corporate sponsored research grant from Elekta.

  13. Double-phase Tc-99m tetrofosmin parathyroid scan in hyperparathyroidism: comparison with ultrasonography

    International Nuclear Information System (INIS)

    Kim, In Soo; Kim, Sang Yoon; Zeon, Seok Kil; Won, Kyoung Sook

    2004-01-01

    This study was performed to evaluate the utility of double-phase Tc-99m Tetrofosmin(TF) parathyroid scan in the detection of pathologic lesions of primary hyperparathyroidism, and comparison with the ultrasonography(US). The double phase TF parathyroid scan of the anterior neck including upper mediastinum with 800 MBq TF were acquired at ten minutes (early phase) and at two hours (delayed phase) after radiopharmaceutical injection, in 24 consecutive patients under the clinical impression of primary hyperparathyroidism and hypercalcaemia. The images were evaluated for abnormal focal areas of increased tracer localization in the anterior neck and superior mediastinum in early phase, and visualization of parathyroid gland radioactivity after wash-out of the thyroid gland radioactivity in delayed phase. US of the anterior neck including upper mediastinum was performed by a diagnostic radiologist in 24 consecutive patients, within one week before or after the scan. The findings of double phase TF parathyroid scan and US were compared with the pathologic results. Ten of 24 patients were surgically explored and pathologic results showed eight adenomas and two hyperplasia. The double phase TF parathyroid scan showed positive findings in seven patients of eight adenomas and one patient of two hyperplasia patients. US image showed positive findings in six patients of eight adenomas and no positive findings of two hyperplasia. The sensitivity of the double phase TF scan for detection of the causes of the primary hyperparathyroidism was 80% and US was 60%. The double phase Tc-99m Tetrofosmin parathyroid scan showed higher sensitivity in detection of the pathologic lesions of primary hyperparathyroidism than ultrasonography

  14. Evaluation of supine and sitting cardiac blood pool scans with sup(99m)Tc-HSA

    International Nuclear Information System (INIS)

    Bunko, Hisashi; Kuwajima, Akira; Hisada, Kinichi

    1977-01-01

    In the differential diagnosis of enlarged cardiac silhouette on plain chest x-ray film, cardiac blood pool scan was usually performed at first. However, small amount of pericardial effusion was difficult to detect on cardiac blood pool scan and differentiation of pericardial effusion from myocardial thickening was sometimes difficult. We evaluated cardiac blood pool scan with sup(99m)Tc-HSA(human serum albumin) and gamma camera imaged on both supine and sitting position, and evaluated diagnostic efficiency of criteria for pericardial effusion of these scans. Fifty-seven patients suspected of having pericardial effusion were included in the study. Sixteen of these patients had pericardial effusion and 2 of these 16 patients had free pleural effusion. Three patients had pleural effusion alone and excluded from the study. Of the five criteria for pericardial effusion, separation between heart and right lung activities was most frequent in both effusion (true positive, TP=100% on both supine and sitting) and no effusion (false positive, FP=18.4% on supine and 23.7% on sitting) groups. However, increased heart and right lung separation on sitting position was rather frequent in effusion group, and this finding was also thought to be typical for effusion but not for myocardial thickening. Decreased cardiohepatic separation on sitting position was frequent in no effusion group, and FP rate was decreased from 18.4% (supine) to 10.5% (sitting). Two patients with both pericardial effusion and free pleural effusion were easily diagnosed on sitting cardiac blood pool scan. With ROC(receiver operating characteristic) curve, three criteria should be agreed on either supine or sitting scan for diagnosis of pericardial effusion, and six criteria should be agreed when both supine and sitting scans were employed for diagnosis of pericardial effusion. (auth.)

  15. Dose profile study on computerized tomography scanning of skull with simulator object

    International Nuclear Information System (INIS)

    Mourao, A.P.

    2011-01-01

    This work presents a comparison among the dose profiles in scanning of computerized tomography of a simulator object of PMMA in its periphery region. To obtain the deposited dose at the PMMA thermoluminescent dosemeters were used positioned at the interior of PMMA simulated object longitudinal to periphery and at the center of cylinder (positions denominated North, South, East, West and Center). Eight scanning were performed of simulator object using the routine protocol for skull in eight different services of radiodiagnostic by TC

  16. Bone scan in the diagnosis and management of acute osteoarticular infection in children

    International Nuclear Information System (INIS)

    Coll, C.; Massardo, T.; Cifras, J.L.; Moya, H.; Verdugo, M.A.; Soza, F.

    2002-01-01

    Introduction: One of the most important causes of children residual damage in the skeleton in Chile are untreated or treated incompletely osteoarticular infections (OAI). The goal of this study was to assess the value of emergency in-hospital pediatric three-phase bone scan in the evaluation of OAI. Methods: The inclusion criteria were: a) high clinical suspicion of acute OAI and b) a suspect of a secondary localization in a known recent OAI. In this prospective study the gold standard was the final diagnosis at discharge. Thirty-eight children were studied with 54 triphasic bone scans using MDP-Tc99m; some with 4th phase. The population mean age was 4±5 years, 66% of them male. Nine children had their first scan prior to surgical intervention (5 of them had also a posterior follow-up scan) and 17 had a post surgery scan (within a median of 5 days ranging from 1-34 days after surgery). Twelve cases were not submitted to surgery. Results: The global analysis showed 28 cases principally articular and 9 osteomyelitis. The most common germ observed were staphylococcus aureus (37%) and staphylococcus coagulase negative (37%), less common was streptococcus (11%); the hip was affected in 41% of the cases, and less frequently knee and femur. Nine patients with preoperative scans were positive with 16 locations foci. Eighty four % of them were confirmed by surgery/culture (true positive) and surgery was performed within 24 h. There were 3 lesions detected in 2 of the patients with no clinical confirmation (16% false positive). There were not any true negative with surgical confirmation in this group, even though, in 2 clinically suspected sites the bone scan were negative and the patients follow-up was not suggestive of infection in those additional localization. Seven children have negative bone scans (without surgery requirement) that did not present posterior clinical symptomatology in the follow-up up to 3 m. In 5 other cases the vascular phase demonstrated only soft

  17. Nodule detection methods using autocorrelation features on 3D chest CT scans

    International Nuclear Information System (INIS)

    Hara, T.; Zhou, X.; Okura, S.; Fujita, H.; Kiryu, T.; Hoshi, H.

    2007-01-01

    Lung cancer screening using low dose X-ray CT scan has been an acceptable examination to detect cancers at early stage. We have been developing an automated detection scheme for lung nodules on CT scan by using second-order autocorrelation features and the initial performance for small nodules (< 10 mm) shows a high true-positive rate with less than four false-positive marks per case. In this study, an open database of lung images, LIDC (Lung Image Database Consortium), was employed to evaluate our detection scheme as an consistency test. The detection performance for solid and solitary nodules in LIDC, included in the first data set opened by the consortium, was 83% (10/12) true-positive rate with 3.3 false-positive marks per case. (orig.)

  18. Synchronized control of spiral CT scan for security inspection device

    International Nuclear Information System (INIS)

    Wang Jue; Jiang Zenghui; Wang Fuquan

    2008-01-01

    In security inspection system of spiral CT, the synchronization between removing and rotating, and the scan synchronization between rotating and sampling influence quality of image reconstruction, so it is difficulty and important that how to realize synchronized scan. According to the controlling demand of multi-slice Spiral CT, the method to realize synchronized scan is given. a synchronized control system is designed, in which we use a industrial PC as the control computer, use magnetic grids as position detectors, use alternating current servo motor and roller motor as drivers respectively drive moving axis and rotating axis. This method can solve the problem of synchronized scan, and has a feasibility and value of use. (authors)

  19. Radiation exposure distribution in patients undergoing CT brain scans

    International Nuclear Information System (INIS)

    Yang Zhanshan; Feng Dinghua; Chang Zichi; Li Shijun

    1989-12-01

    The distribution of surface exposures in patients undergoing single and multiple computerized tomographic brain scans with Hitachi CT-W500 was measured by LiF(Mg, Ti) thermoluminescent dosimetry. It was found that there was no significant difference in the sufrace exposures from different scanning slices. However, the exposure doses at different scanning angles around the head were different significantly. The reference point of the maximum surface exposure was at the temporal part of the head. the maximum surface exposure was at 1.65 x 10 -3 C·kg -1 while the average exposure was 1.55 x 10 -3 C·kg -1 . The ratio of the average dose resulting from nine scans to that from a single scan was 1.3, and the surface exposure contribution of scattered radiation was computed. At the same time the radiation doses to eyes, thyroid, chest and gonads of patiens at corresponding position were also measured and were compared with those from CT cranial scans in children and skull radiographic procedures respectively

  20. Scanning For Hotspots In Lamp Filaments

    Science.gov (United States)

    Powers, Charles E.; Van Sant, Tim; Leidecker, Henning

    1993-01-01

    Scanning photometer designed for use in investigation of failures of incandescent lamp filaments. Maps brightness as function of position along each filament to identify bright (hot) spots, occurring at notches and signifying incipient breaks or rewelds. Also used to measure nonuniformity in outputs of such linear devices as light-emitting diodes, and to measure diffraction patterns of lenses.

  1. Indications of CT scan after minor head trauma in children. Can age younger than 2 years be a risk factor?

    International Nuclear Information System (INIS)

    Ozaki, Mitsunori; Seo, Yoshinobu; Nakamura, Hirohiko

    2010-01-01

    The indications of CT scan after minor head trauma in children are often discussed, including risks of radiation-induced malignancy. Our aim is to identify whether children younger than 2 years have greater risk of traumatic brain injury compared to older children. We enrolled and analysed 1,830 patients younger than 7 years who underwent CT scans after head trauma in our institute. Patients without any symptoms (n=916) were defined as Group A (age<2: n=391, age 2-6: n=525). Patients with extracranial traumatic findings such as scalp hematoma or laceration, and without any neurological symptoms (n=600) were defined as Group B (age<2: n=163, age 2-6: n=437). In order to analyze whether children younger than 2 years have risks of abnormal CT findings due to head trauma, we used the chi-square test in both Group A and Group B. A P-value of less than 0.05 was considered statistically significant. In Group A, there was no significant difference in the frequency of abnormal CT findings between the younger and older groups (p=0.526). In Group B, however, there was a significant difference between those groups (p=0.0186). We suggest that, based on our findings, children younger than 2 years without any symptoms don't have a greater risk of brain injury compared to older children after minor head trauma. This study might contribute to save those children from receiving unnecessary radiation. (author)

  2. A fully automated non-external marker 4D-CT sorting algorithm using a serial cine scanning protocol.

    Science.gov (United States)

    Carnes, Greg; Gaede, Stewart; Yu, Edward; Van Dyk, Jake; Battista, Jerry; Lee, Ting-Yim

    2009-04-07

    Current 4D-CT methods require external marker data to retrospectively sort image data and generate CT volumes. In this work we develop an automated 4D-CT sorting algorithm that performs without the aid of data collected from an external respiratory surrogate. The sorting algorithm requires an overlapping cine scan protocol. The overlapping protocol provides a spatial link between couch positions. Beginning with a starting scan position, images from the adjacent scan position (which spatial match the starting scan position) are selected by maximizing the normalized cross correlation (NCC) of the images at the overlapping slice position. The process was continued by 'daisy chaining' all couch positions using the selected images until an entire 3D volume was produced. The algorithm produced 16 phase volumes to complete a 4D-CT dataset. Additional 4D-CT datasets were also produced using external marker amplitude and phase angle sorting methods. The image quality of the volumes produced by the different methods was quantified by calculating the mean difference of the sorted overlapping slices from adjacent couch positions. The NCC sorted images showed a significant decrease in the mean difference (p < 0.01) for the five patients.

  3. Reconstruction of a time-averaged midposition CT scan for radiotherapy planning of lung cancer patients using deformable registration.

    Science.gov (United States)

    Wolthaus, J W H; Sonke, J J; van Herk, M; Damen, E M F

    2008-09-01

    lower lobe lung tumors move with amplitudes of up to 2 cm due to respiration. To reduce respiration imaging artifacts in planning CT scans, 4D imaging techniques are used. Currently, we use a single (midventilation) frame of the 4D data set for clinical delineation of structures and radiotherapy planning. A single frame, however, often contains artifacts due to breathing irregularities, and is noisier than a conventional CT scan since the exposure per frame is lower. Moreover, the tumor may be displaced from the mean tumor position due to hysteresis. The aim of this work is to develop a framework for the acquisition of a good quality scan representing all scanned anatomy in the mean position by averaging transformed (deformed) CT frames, i.e., canceling out motion. A nonrigid registration method is necessary since motion varies over the lung. 4D and inspiration breath-hold (BH) CT scans were acquired for 13 patients. An iterative multiscale motion estimation technique was applied to the 4D CT scan, similar to optical flow but using image phase (gray-value transitions from bright to dark and vice versa) instead. From the (4D) deformation vector field (DVF) derived, the local mean position in the respiratory cycle was computed and the 4D DVF was modified to deform all structures of the original 4D CT scan to this mean position. A 3D midposition (MidP) CT scan was then obtained by (arithmetic or median) averaging of the deformed 4D CT scan. Image registration accuracy, tumor shape deviation with respect to the BH CT scan, and noise were determined to evaluate the image fidelity of the MidP CT scan and the performance of the technique. Accuracy of the used deformable image registration method was comparable to established automated locally rigid registration and to manual landmark registration (average difference to both methods noise of individual 4D CT scan frames. We implemented an accurate method to estimate the motion of structures in a 4D CT scan. Subsequently, a

  4. Osmotic blood-brain barrier modification: clinical documentation by enhanced CT scanning and/or radionuclide brain scanning

    International Nuclear Information System (INIS)

    Neuwelt, E.A.; Specht, H.D.; Howieson, J.; Haines, J.E.; Bennett, M.J.; Hill, S.A.; Frenkel, E.P.

    1983-01-01

    Results of initial clinical trials of brain tumor chemotherapy after osmotic blood-brain barrier disruption are promising. In general, the procedure is well tolerated. The major complication has been seizures. In this report, data are presented which indicate that the etiology of these seizures is related to the use of contrast agent (meglumine iothalamate) to monitor barrier modification. A series of 19 patients underwent a total of 85 barrier modification procedures. Documentation of barrier disruption was monitored by contrast-enhanced computed tomographic (CT) scanning, radionuclide brain scanning, or a combination of both techniques. In 56 procedures (19 patients) monitored by enhanced CT, seizures occurred a total of 10 times in eight patients. Twenty-three barrier modification procedures (in nine of these 19 patients) documented by nuclear brain scans alone, however, resulted in only one focal motor seizure in each of two patients. In eight of the 19 patients who had seizures after barrier disruption and enhanced CT scan, four subsequently had repeat procedures monitored by radionuclide scan alone. In only one of these patients was further seizure activity noted; a single focal motor seizure was observed. Clearly, the radionuclide brain scan does not have the sensitivity and spatial resolution of enhanced CT, but at present it appears safer to monitor barrier modification by this method and to follow tumor growth between barrier modifications by enhanced CT. Four illustrative cases showing methods, problems, and promising results are presented

  5. Clinical discussion of adrenal scan by 131I-adosterol

    International Nuclear Information System (INIS)

    Kubo, Atsushi

    1976-01-01

    131 I-adosterol adrenal scan was conducted to 31 patients. Clear positive images were obtained at the adrenal gland at the side of cortical adenoma on scintigram in all of 5 patients with primary aldosteronism and 5 patients with Cushing's syndrome. It was found that the quantitative measurements of 131 I-adosterol % uptake and of right-to-left uptake ratio do not only make a regional diagnosis of adrenocortical tumor more positive, but also they make the state of adrenocortical function known to an extent. Adrenal scan is easy to be used, and is non-invasive to patients. The obtained results are diagnostically valuable. It is considered that 131 I-Adosterol is an excellent radiopharmaceutical having the sufficient efficacy for adrenal diseases. (Ichikawa, K.)

  6. Scanning with Au198 in experimental hepatic trauma

    International Nuclear Information System (INIS)

    Faifer, J.G.; Macedo, A.R. de; Vicentini, M.L.M.; Hossne, W.S.

    1977-01-01

    Scintiscanning of the liver with Au 198 was performed in 30 mongrel dogs, with the purpose of evaluating the importance of this method in the diagnostic of liver traumatisms. In 18 animals the scanning was performed after 3 differents types of hepatic trauma: intraparenchymal hematoma, stab wound and lasceration of liver. In 12 dogs without hepatic trauma the scanning was performed with the purpose of establishing the pattern of the normal liver scan in the dog. Results indicate that scintiscanning of the liver is a good propaedeutic method in the evaluation of the presence and localization of traumatic hepatic lesion [pt

  7. T-scan III system diagnostic tool for digital occlusal analysis in orthodontics - a modern approach.

    Science.gov (United States)

    Trpevska, Vesna; Kovacevska, Gordana; Benedeti, Alberto; Jordanov, Bozidar

    2014-01-01

    This systematic literature review was performed to establish the mechanism, methodology, characteristics, clinical application and opportunities of the T-Scan III System as a diagnostic tool for digital occlusal analysis in different fields of dentistry, precisely in orthodontics. Searching of electronic databases, using MEDLINE and PubMed, hand searching of relevant key journals, and screening of reference lists of included studies with no language restriction was performed. Publications providing statistically examined data were included for systematic review. Twenty potentially relevant Randomized Controlled Trials (RCTs) were identified. Only ten met the inclusion criteria. The literature demonstrates that using digital occlusal analysis with T-Scan III System in orthodontics has significant advantage with regard to the capability of measuring occlusal parameters in static positions and during dynamic of the mandible. Within the scope of this systematic review, there is evidence to support that T-Scan system is rapid and accurate in identifying the distribution of the tooth contacts and it shows great promise as a clinical diagnostic screening device for occlusion and for improving the occlusion after various dental treatments. Additional clinical studies are required to advance the indication filed of this system. Importance of using digital occlusal T-Scan analysis in orthodontics deserves further investigation.

  8. Technological features and clinical feasibility of megavoltage CT scanning

    International Nuclear Information System (INIS)

    Nakagawa, Keiichi; Aoki, Yukimasa; Akanuma, Atsuo; Sakata, Kouichi; Karasawa, Katsuyuki; Terahara, Atsurou; Onogi, Yuzou; Hasezawa, Kenji; Sasaki, Yasuhito

    1992-01-01

    Megavoltage CT scanning using 4-MV and 6-MV radiotherapy beams has been developed and applied to verify errors in patient positioning. A detector system composed of 120 pairs of cadmium tungstate scintillators with photodiodes is mounted to the treatment unit at a distance of 160 cm from the beam source. Image reconstruction is performed with a standard filtered back-projection algorithm. Scanning time and reconstruction time for a slice is approximately 35 s and 60 s respectively. Although spatial resolution is as large as 4 mm, it has sufficient image quality to be applied for treatment planning and verification. The delivered dose with 4 MV and 6 MV is about 1.4 cGy and 2.8 cGy respectively. When a megavoltage CT image is taken in treatment position, the positioning errors are easily detected by comparing it with diagnostic CT sections for treatment planning. Several clinical examples are presented. (orig.)

  9. Clinical efficacy of FDG-PET scan as preoperative diagnostic tool in cervical cancer stage Ib and IIa: comparison between the results of FDG-PET scan and operative findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Hoon

    1999-12-01

    This study was done to evaluate the clinical feasibility of FDG-PET scan for routine preoperative diagnostic methods in cervical carcinoma. PET-scans were performed from March, 1999 to November, 1999. There were 6 stage Ib and 7 IIa patients and all patients were performed radical hysterectomy and bilateral pelvic lymph node dissections and were evaluated by FDG-PET scan before operation. The mean age of the patients were 50.3 years old. Six cases had lymph node metastases by pelvis MRI, and three cases by FDG-PET scan. We could not find any lymph node metastases at surgery in 3 patients (50.0%) among 6 patients who were diagnosed by nodal metastases by pelvis MRI. And we found 1 patients with nodal metastases who had negative findings by pelvis MRI. By FDG-PET scan, we could find metastases in all positive patients. But we also found 2 additional metastatic cases in the patients with negative findings. In this study, the comparison was very difficult due to the individual differences in the comparison would be made by site-specific not person. The sensitivity of MRI and FDG-PET scan were 50.0% and 30.0%. The specificity were 94.1 % and 95.6%. The positive predictive value were 55.6 % and 50.0 %. In conclusion, we could find any superiority of FDG-PET scan in the diagnosis of lymph node metastases the pelvis MRI. So there are limitations to use the FDG-PET scan in the routine preoperative diagnostic tools in cervical cancer. But if we have more experiences to use the FDG-PET scan such as precise cut-off value of SUV and combination of other imaging technique, the FDG-PET scan are still promising diagnostic tools in cervical cancer.

  10. Indium-granulocyte scanning in the painful prosthetic joint

    International Nuclear Information System (INIS)

    Pring, D.J.; Henderson, R.G.; Keshavarzian, A.; Rivett, A.G.; Krausz, T.; Coombs, R.R.; Lavender, J.P.

    1986-01-01

    The value of indium-111-labeled granulocyte scanning to determine the presence of infection was assessed in 50 prosthetic joints (41 of which were painful) in 40 patients. Granulocytes were obtained from the patients' blood and labeled in plasma with indium 111 tropolonate. Abnormal accumulation of indium 111 in the region of the prosthesis was noted. Proven infection occurred in 11 prostheses, and all of the infections were detected by indium-111-labeled granulocyte scanning. Nineteen were not infected (including nine asymptomatic controls) and only two produced false-positive scans. This represents a specificity of 89.5%, sensitivity of 100%, and overall accuracy of 93.2%. These results compare favorably with plain radiography. There was no radiologic evidence of infection in three of the infected prostheses, and 10 of the noninfected prostheses had some radiologic features that suggested sepsis. We conclude that indium-granulocyte scanning can reliably detect or exclude infection in painful prosthetic joints and should prove useful in clinical management

  11. Nonlinear Optical Characteristics of Crystal VioletDye Doped Polystyrene Films by Using Z-Scan Technique

    Directory of Open Access Journals (Sweden)

    Mahasin F. Hadi

    2017-07-01

    Full Text Available Z-scan technique was employed to study the nonlinear optical properties (nonlinear refractive index and nonlinear absorption coefficient for crystal violet doped polystyrene films as a function of doping ratio in chloroform solvent. Samples exhibits in closed aperture Z-scan positive nonlinear refraction (self-focusing. While in the open aperture Z-scan gives reverse saturation absorption (RSA (positive absorption for all film with different doping ratio making samples candidates for optical limiting devices for protection of sensors and eyes from energetic laser light pulses under the experimental conditions.

  12. The Ulysses fast latitude scans: COSPIN/KET results

    Directory of Open Access Journals (Sweden)

    B. Heber

    2003-06-01

    Full Text Available Ulysses, launched in October 1990, began its second out-of-ecliptic orbit in December 1997, and its second fast latitude scan in September 2000. In contrast to the first fast latitude scan in 1994/1995, during the second fast latitude scan solar activity was close to maximum. The solar magnetic field reversed its polarity around July 2000. While the first latitude scan mainly gave a snapshot of the spatial distribution of galactic cosmic rays, the second one is dominated by temporal variations. Solar particle increases are observed at all heliographic latitudes, including events that produce >250 MeV protons and 50 MeV electrons. Using observations from the University of Chicago’s instrument on board IMP8 at Earth, we find that most solar particle events are observed at both high and low latitudes, indicating either acceleration of these particles over a broad latitude range or an efficient latitudinal transport. The latter is supported by "quiet time" variations in the MeV electron background, if interpreted as Jovian electrons. No latitudinal gradient was found for >106 MeV galactic cosmic ray protons, during the solar maximum fast latitude scan. The electron to proton ratio remains constant and has practically the same value as in the previous solar maximum. Both results indicate that drift is of minor importance. It was expected that, with the reversal of the solar magnetic field and in the declining phase of the solar cycle, this ratio should increase. This was, however, not observed, probably because the transition to the new magnetic cycle was not completely terminated within the heliosphere, as indicated by the Ulysses magnetic field and solar wind measurements. We argue that the new A<0-solar magnetic modulation epoch will establish itself once both polar coronal holes have developed.Key words. Interplanetary physics (cosmic rays; energetic particles; interplanetary magnetic fields

  13. Role of B-scan ultrasonography in pre-operative cataract patients.

    Science.gov (United States)

    Qureshi, Manzoor A; Laghari, Khalida

    2010-01-01

    To visualize the posterior portion of eye globe in dense cataract patients with B scan ultrasound, and to find out any posterior segment lesion in such pre-operative cases. We performed diagnostic B-scan ultrasound on 750 cataract patients before surgery. This was a prospective diagnostic study which was conducted in the Department of Opthalmology, Liaquat University Eye Hospital, Hyderabad Sind, Pakistan from January 2007 to July 2007. Detailed history and some basic eye examination techniques, like slit lamp and tonometry were done in two groups of patients, traumatic (71) and non traumatic(679). Patients in the age range of 1 to 79 years of both sexes were included. Patients having already posterior segment lesions and those who had previous history of ocular surgery were excluded from the study. An ultrasound machine Nidek Echo Scan Model US-3300 with a probe of direct contact was used. Out of 750 patients, 90 patients had posterior segment lesions. Among traumatic group of 71 patients, 39 (55%) had positive posterior segment lesions, while in the non traumatic group of 679 patients, only 51 (7%) cases had positive posterior segment lesions. Out of the 90 positive cases, 25 (3%) had retinal detachment, 14 (2%) had posterior vitreous detachment, 24 (3%) had vitreous hemorrhage, 12 (2%) were asteroid hyolosis, while posterior staphyloma and intra-ocular foreign body were found with the frequency of 9 (1.2%) and 6 (1%), respectively. We concluded that two dimensional B-scan ultrasound can be one of the diagnostic tool for the detection of hidden posterior segment lesions and can be performed routinely in pre-operative cataract patients, as this would help in surgical planning. In cases, where a two dimensional B-scan is not sufficient or helpful. a three dimensional ultrasound would be justified.

  14. Medical Radioisotope Scanning, Vol. II. Proceedings of the Symposium on Medical Radioisotope Scanning

    International Nuclear Information System (INIS)

    1964-01-01

    Medical applications of radioisotopes continue to grow in number and importance and medical centres in almost all countries of the world are now using radioactive materials both in the diagnosis and treatment of disease. An increasing proportion of these applications involves studies of the spatial distribution of radioactive material within the human body, for which purpose highly specialized scanning methods have been elaborated. By these methods it is possible to study the position, size and functional state of different organs, to detect tumours, cysts and other abnormalities and to obtain much useful information about regions of the body that are otherwise inaccessible, except by surgery. Progress in scanning methods in recent years has been very rapid and there have been many important advances in instrumentation and technique. The development of new forms of the gamma camera and of colour-scanning techniques are but two examples of recent improvements. The production of new radioisotopes and new labelled compounds has further extended the scope of these methods. To survey these new advances the International Atomic Energy Agency held a Symposium on Medical Radioisotope Scanning in Athens from 20-24 April 1964. The scientific programme of the meeting covered all aspects of scanning methods including theoretical principles, instrumentation, techniques and clinical applications. The World Health Organization assisted in the selection of papers by providing a consultant to the selection committee. The meeting followed the earlier IAEA/WHO Seminar on Medical Radioisotope Scanning in Vienna in 1959, which was attended by 36 participants and at which 14 papers were presented. Some idea of the growth of interest in the subject may be gained from the fact that the Symposium was attended by 160 participants from 26 countries and 4 international organizations, and that 58 papers were presented. The published proceedings, comprising two volumes, contain all the

  15. Bone scanning as a routine examination of patients with mammary carcinoma; a critical consideration

    International Nuclear Information System (INIS)

    Heslinga, J.M.; Pauwels, E.K.J.; Zwaveling, A.

    1982-01-01

    The usefulness of bone scanning as a routine examination was evaluated in 136 female patients with mammary carcinoma of whom 81 were staged as Columbia A and 55 as Columbia B/C. The preoperative bone scanning was positive in only 4 patients (2.9%). Consequently, bone scanning is no longer performed in the authors clinic for the preoperative detection of skeletal metastases. Bone scanning as a routine examination at 6-month intervals does not appear to be useful for the first 4 years of the follow-up, either. Most of the patients with a positive bone scan displayed other signs of skeletal metastases at the same time, such as ostealgia and a raised serum alkaline phosphatase level. Further increase of the frequency of bone scanning during the follow-up period would increase the costs considerably, almost prohibitively, even apart from the question whether such a measure might indeed significantly influence the patient's prognosis. The authors conclude that bone scanning should only be performed on the basis of the anamnesis, physical and laboratory findings, both prior to operation and during the follow-up period. (Auth.)

  16. Comparative yield of positive brain Computed Tomography after implementing the NICE or SIGN head injury guidelines in two equivalent urban populations

    International Nuclear Information System (INIS)

    Summerfield, R.; Macduff, R.; Davis, R.; Sambrook, M.; Britton, I.

    2011-01-01

    Aims: To compare the yield of positive computed tomography (CT) brain examinations after the implementation of the National Institute for Clinical Excellence (NICE) or the Scottish Intercollegiate Guidance Network (SIGN) guidelines, in comparable urban populations in two teaching hospitals in England and Scotland. Materials and methods: Four hundred consecutive patients presenting at each location following a head injury who underwent a CT examination of the head according to the locally implemented guidelines were compared. Similar matched populations were compared for indication and yield. Yield was measured according to (1) positive CT findings of the sequelae of trauma and (2) intervention required with anaesthetic or intensive care unit (ICU) support, or neurosurgery. Results: The mean ages of patients at the English and Scottish centres were 49.9 and 49.2 years, respectively. Sex distribution was 64.1% male and 66.4% male respectively. Comparative yield was 23.8 and 26.5% for positive brain scans, 3 and 2.75% for anaesthetic support, and 3.75 and 2.5% for neurosurgical intervention. Glasgow Coma Score (GCS) 10% yield of positive scans. The choice of guideline to follow should be at the discretion of the local institution. The indications GCS <13 and clinical or radiological evidence of a skull fracture are highly predictive of intracranial pathology, and their presence should be an absolute indicator for fast-tracking the management of the patient.

  17. Driving and positioning arrangement for radiography

    International Nuclear Information System (INIS)

    Ingham, W.E.; Williams, A.M.

    1980-01-01

    Details of the design of novel equipment for use in computerised axial tomographic scanning are given. The apparatus enables accurate driving and positioning of the tomographic apparatus while the patient retains a horizontal position. Furthermore, the movement is effected automatically and in a controllable manner. (UK)

  18. Case report: a position to delineate pelvic radionuclide uptake

    International Nuclear Information System (INIS)

    Giga, J.H.L.; Jimenez, T.; Lobred, S.K.

    1981-01-01

    An innovative position is described for patients undergoing technetium 99m bone imaging in the pelvic area. The position, called Gaga squat, requires the patient to sit on the scintillation camera face. This allows recognition of metastatic disease in areas which may be masked by bladder activity. The view may also be used to complement conventional views for studies such as TcO 4 testicular scans or gallium-67 scans

  19. New approach to imaging HIV-positive patients with pyrexia of undetermined origin

    International Nuclear Information System (INIS)

    Buscombe, J.; Miller, R.; Lui, D.; Ell, P.J.

    1990-01-01

    This paper established if imaging with Tc-99m human immunoglobulin (HIG) in addition to Ga-67 citrate increased the diagnostic sensitivity in patients who have pyrexia of unknown origin (PUO) and who have tested positive for human immunodeficiency virus (HIV). The authors studied 18 HIV-positive patients with PUO for 3 or more weeks. Imaging was performed 4 and 20 hours after administration of 200 MBq of Tc-99m HIG and 24, 48, and (if indicated) 72 hours after administration of 300 MBq of Ga-67. Anterior whole body and relevant spot view were obtained for both agents. Twenty-four sites of infection were confirmed microbiologically in 12 patients. Ga-67 scan results were positive in 22 of these sites, and Tc-99m HIG results were positive in 13; the nine Ga-positive sites that were Tc-negative were intrathoracic (one Pneumocystis carinii, eight Mycobacterium intracellulare)

  20. Prognostic impact of pre-transplantation computed tomography and 67gallium scanning in chemosensitive diffuse large B cell lymphoma patients undergoing hematopoietic stem-cell transplantation

    International Nuclear Information System (INIS)

    Escobar, Ignacio G.; Alonso, Pilar T.; Barrigon, Dolores C.; Perez-Simon, Jose A.; Mateos Manteca, Maria V.; San Miguel Izquierdo, Jesus F.

    2008-01-01

    In the present study, we evaluated computed tomography (CT) and 67 gallium scanning ( 67 Ga scan) pre-transplant as prognostic factors for overall survival (OS) and event-free survival (EFS) in patients with diffuse large B cell lymphoma, undergoing high-dose chemotherapy and stem-cell transplantation. Forty-two patients were included. Of these, 9 (21%) had both positive CT and 67 Ga scans, 17 (41%) negative results with both techniques, and 16 (38%) positive CT/negative 67 Ga scan. Whole-body planar imaging and single-photon emission computed tomography (SPECT) were performed 72 h after an intravenous administration of 67 Ga citrate measuring between 7 mCi and 10 mCi (259-370 MBq). Patients with positive CT/positive 67 Ga scan had a significantly worse EFS and OS at 5 years than those with negative 67 Ga scan regardless of whether it was associated with a positive or a negative CT scan (29% and 16% vs. 81% and 93% vs. 88% and 100%, respectively, P 67 Ga scan and those with positive CT/negative 67 Ga scan, with an EFS and OS at 5 years of 88% versus 81% and 100% versus 93%, respectively. In multivariate analysis, the presence of a pre-transplant positive CT/ 67 Ga scans adversely influenced both EFS and OS [HR 8, 95% confidence interval (CI) (1.4-38), P=0.03 and HR 2; 95% CI (1.3-8), P=0.02, respectively]. 67 Ga scan helps to identify, in the pre-transplant evaluation, two groups with a different outcome: one group of patients with positive CT and negative 67 Ga scans pre-transplant, who showed a favorable outcome with a low rate of relapse, and the other group of patients with both positive CT and 67 Ga scans pre-transplant, who showed a poor prognosis and did not benefit from autologous stem-cell transplantation. They should have been offered other therapeutic strategies. (author)

  1. NEW SCANNING DEVICE FOR SCANNING TUNNELING MICROSCOPE APPLICATIONS

    NARCIS (Netherlands)

    SAWATZKY, GA; Koops, Karl Richard

    A small, single piezo XYZ translator has been developed. The device has been used as a scanner for a scanning tunneling microscope and has been tested successfully in air and in UHV. Its simple design results in a rigid and compact scanning unit which permits high scanning rates.

  2. Prospective evaluation of radionuclide scanning in detection of intestinal necrosis in neonatal necrotizing enterocolitis

    International Nuclear Information System (INIS)

    Haase, G.M.; Sfakianakis, G.N.; Lobe, T.E.; Boles, E.T.

    1981-01-01

    The ability of external imaging to demonstrate intestinal infarction in neonatal necrotizing enterocolitis (NEC) was prospectively evaluated. The radiopharmaceutical technetium--99m diphosphonate was injected intravenously and the patients subsequently underwent abdominal scanning. Clinical patient care and interpretation of the images were entirely independent throughout the study. Of 33 studies, 7 were positive, 4 were suspicious, and 22 were negative. One false positive study detected ischemia without transmural infarction. The second false positive scan occurred postoperatively and was due to misinterpretation of the hyperactivity along the surgical incision. None of the suspicious cases had damaged bowel. The two false negative studies clearly failed to demonstrate frank intestinal necrosis. The presence of very small areas of infarction, errors in technical settings, subjective interpretation of scans and delayed clearance of the radionuclide in a critically ill neonate may all limit the accuracy of external abdominal scanning. However, in spite of an error rate of 12%, it is likely that this technique will enhance the present clinical, laboratory, and radiologic parameters of patient management in NEC

  3. Quantitative Assessment of Orbital Implant Position--A Proof of Concept.

    Directory of Open Access Journals (Sweden)

    Ruud Schreurs

    Full Text Available In orbital reconstruction, the optimal location of a predefined implant can be planned preoperatively. Surgical results can be assessed intraoperatively or postoperatively. A novel method for quantifying orbital implant position is introduced. The method measures predictability of implant placement: transformation parameters between planned and resulting implant position are quantified.The method was tested on 3 human specimen heads. Computed Tomography scans were acquired at baseline with intact orbits (t0, after creation of the defect (t1 and postoperatively after reconstruction of the defect using a preformed implant (t2. Prior to reconstruction, the optimal implant position was planned on the t0 and t1 scans. Postoperatively, the planned and realized implant position were compared. The t0 and t2 scans were fused using iPlan software and the resulting implant was segmented in the fused t2 scan. An implant reference frame was created (Orbital Implant Positioning Frame; the planned implant was transformed to the reference position using an Iterative Closest Point approach. The segmentation of the resulting implant was also registered on the reference position, yielding rotational (pitch, yaw, roll as well as translational parameters of implant position.Measurement with the Orbital Implant Positioning Frame proved feasible on all three specimen. The positional outcome provided more thorough and accurate insight in resulting implant position than could be gathered from distance measurements alone. Observer-related errors were abolished from the process, since the method is largely automatic.A novel method of quantifying surgical outcome in orbital reconstructive surgery was presented. The presented Orbital Implant Positioning Frame assessed all parameters involved in implant displacement. The method proved to be viable on three human specimen heads. Clinically, the method could provide direct feedback intraoperatively and could improve

  4. A robust method for processing scanning probe microscopy images and determining nanoobject position and dimensions

    NARCIS (Netherlands)

    Silly, F.

    2009-01-01

    P>Processing of scanning probe microscopy (SPM) images is essential to explore nanoscale phenomena. Image processing and pattern recognition techniques are developed to improve the accuracy and consistency of nanoobject and surface characterization. We present a robust and versatile method to

  5. Nuclear Scans

    Science.gov (United States)

    Nuclear scans use radioactive substances to see structures and functions inside your body. They use a special ... images. Most scans take 20 to 45 minutes. Nuclear scans can help doctors diagnose many conditions, including ...

  6. Study of 67Ga scan in sarcoidosis

    International Nuclear Information System (INIS)

    Han Lijun; Qu Wanyin; Liu Xiuqin

    1997-01-01

    Gallium scan and serum angiotensin-converting enzyme assay (SACE) were compared in patients with sarcoidosis. The examination of 67 Ga scan, SACE determination, pulmonary function test, chest CT and chest X-ray in 24 cases with sarcoidosis were studied. The results revealed that 4 of 24 cases had obviously high uptake of 67 Ga exceeding hepatic activity (3+) in clinical active stage, 3 patients had resembling the Greek letter lambda, symmetrically located in bilateral hilar lymph nodes, and among them two had an uptake of 67 Ga in the bilateral lacrimal and parotid gland simulating 'Panda Face'. 8 of 20 cases with inactive sarcoidosis had an abnormal 67 Ga scan (1+). In those patients with normal SACE level but increased uptake of 67 Ga, active stage of disease was demonstrated and steroid therapy was indicated. Gallium scan is a valuable method for the staging of its activity and evaluation of the therapeutic effect in the follow-up patients with sarcoidosis

  7. Assessment of hybrid rotation-translation scan schemes for in vivo animal SPECT imaging

    International Nuclear Information System (INIS)

    Xia Yan; Liu Yaqiang; Wang Shi; Ma Tianyu; Yao Rutao; Deng Xiao

    2013-01-01

    To perform in vivo animal single photon emission computed tomography imaging on a stationary detector gantry, we introduced a hybrid rotation-translation (HRT) tomographic scan, a combination of translational and limited angle rotational movements of the image object, to minimize gravity-induced animal motion. To quantitatively assess the performance of ten HRT scan schemes and the conventional rotation-only scan scheme, two simulated phantoms were first scanned with each scheme to derive the corresponding image resolution (IR) in the image field of view. The IR results of all the scan schemes were visually assessed and compared with corresponding outputs of four scan scheme evaluation indices, i.e. sampling completeness (SC), sensitivity (S), conventional system resolution (SR), and a newly devised directional spatial resolution (DR) that measures the resolution in any specified orientation. A representative HRT scheme was tested with an experimental phantom study. Eight of the ten HRT scan schemes evaluated achieved a superior performance compared to two other HRT schemes and the rotation-only scheme in terms of phantom image resolution. The same eight HRT scan schemes also achieved equivalent or better performance in terms of the four quantitative indices than the conventional rotation-only scheme. As compared to the conventional index SR, the new index DR appears to be a more relevant indicator of system resolution performance. The experimental phantom image obtained from the selected HRT scheme was satisfactory. We conclude that it is feasible to perform in vivo animal imaging with a HRT scan scheme and SC and DR are useful predictors for quantitatively assessing the performance of a scan scheme. (paper)

  8. Play and optimal welfare: Does play indicate the presence of positive affective states?

    Science.gov (United States)

    Ahloy-Dallaire, Jamie; Espinosa, Julia; Mason, Georgia

    2017-11-16

    Play is commonly used to assess affective states in both humans and non-human animals. Play appears to be most common when animals are well-fed and not under any direct threats to fitness. Could play and playfulness therefore indicate pre-existing positive emotions, and thence optimal animal welfare? We examine this question by surveying the internal and external conditions that promote or suppress play in a variety of species, starting with humans. We find that negative affective states and poor welfare usually do suppress play (although there are notable exceptions where the opposite occurs). Furthermore, research in children suggests that beyond the frequency or total duration of play, poor welfare may additionally be reflected in qualitative aspects of this heterogeneous behaviour (e.g. display of solitary over social play; and the 'fragmentation' of play bouts) that are often overlooked in animals. There are surprisingly few studies of play in subjects with pre-existing optimal welfare or in unambiguously highly positive affective states, making it currently impossible to determine whether play can distinguish optimal or good welfare from merely neutral welfare. This therefore represents an important and exciting area for future research. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Patient-provider relationship predicts mental and physical health indicators for HIV-positive men who have sex with men.

    Science.gov (United States)

    Bankoff, Sarah M; McCullough, Mary B; Pantalone, David W

    2013-06-01

    We used secondary data analysis to examine associations among aspects of patient-provider relationships and mental and physical health indicators. Positive patient perceptions of patient-provider relationships were associated with fewer mental health symptoms in this outpatient sample of HIV-positive men who have sex with men (N = 171). Regression analyses revealed the role of anxiety and depression in explaining associations between two aspects of patient-provider relationships (i.e. quality of information offered and provider interactional style) and health-related quality of life. The findings demonstrated the importance of patient-provider relationships to improving physical health and functioning and maintaining engagement in care, among HIV-positive men who have sex with men.

  10. Correlation between bone scan findings and serum PSA level in prostate cancer patients in Bangladesh: both newly diagnosed and hormonally treated cases

    International Nuclear Information System (INIS)

    Yasmeen, S.; Nasreen, F.; Kabir, M.F.

    2007-01-01

    who received treatment for their prostate cancer. All patients underwent a bone scan and serum PSA measurement. Results: Only 6% of 242 patients with newly diagnosed prostate cancer had positive bone scan on initial evaluation. Scans were positive in 0 of 112 with PSA level below 10 ng/ml, 5 of 76 with PSA level between 10 to 20 ng/ml and 09 of 54 with PSA level above 30 ng/ml. In newly diagnosed cases the sensitivity of PSA in predicting bony mets was found to be appreciably high and did not decrease notably with the increase of cut off value from 10ng/ml to 30ng/ml. From this study it was evident that PSA level between 10-30ng/ml has optimum sensitivity and specificity in newly diagnosed cases. In case of patients on hormone therapy bone scan was positive in 49 cases at PSA level 20ng/ml. PSA alone would have failed to detect a significant number of patients in hormonally treated cases indicating a low sensitivity in this group. Conclusion: Patients with newly diagnosed and untreated prostate cancer should undergo bone scintigraphy if there is bone pain. Recent reports discourage the routine use of a bone scan when serum PSA is <20ng/ml. In newly diagnosed cases, the incidence of bone metastasis increased with the increasing level of serum PSA. The likelihood of bone metastasis is low in newly diagnosed cases when PSA level is low. In hormonally treated cases bone scan was positive even when the PSA level was low. PSA is a major predictor for positive bone scan. About two third of the patients analyzed were in the low risk group and elimination of a bone scan in these patients would result in considerable economic saving. Serum PSA level may remain low even in presence of metastases in hormonally treated cases. For assessment of hormonally treated cases bone scan should be done. (author)

  11. SU-F-207-03: Dosimetric Effect of the Position of Arms in Torso CT Scan with Tube Current Modulation

    International Nuclear Information System (INIS)

    Liu, H; Gao, Y; Xu, X; Zhuo, W; Wu, J

    2015-01-01

    Purpose: To evaluate the patient organ dose differences between the arms-raised and arms-lowered postures in Torso multidetector computed tomography (MDCT) scan protocols with tube current modulation (TCM). Methods: Patient CT organ doses were simulated using the Monte Carlo method with human phantoms and a validated CT scanner model. A set of adult human phantoms with arms raised and arms lowered postures were developed using advanced BREP-based mesh surface geometries. Organ doses from routine Torso scan protocols such as chest, abdomen-pelvis, and CAP scans were simulated. The organ doses differences caused by two different posutres were investigated when tube current modulation (TCM) were applied during the CT scan. Results: With TCM applied, organ doses of all the listed organs of arms-lowered posture phantom are larger than those of arms raised phantom. The dose difference for most of the organs or tissues are larger than 50%, and the skin doses difference for abdomen-pelvis scan even reaches 112.03%. This is due to the fact that the tube current for patient with arms-lowered is much higher than for the arms raised posture. Conclusion: Considering CT scan with TCM, which is commonly applied clinically, patients who could not raise their arms will receive higher radiation dose than the arms raised patient, with dose differences for some tissues such as the skin being larger than 100%. This is due to the additional tube current necessary to penetrate the arms while maintaining consistent image quality. National Nature Science Foundation of China(No.11475047)

  12. An RFID-Based Smart Structure for the Supply Chain: Resilient Scanning Proofs and Ownership Transfer with Positive Secrecy Capacity Channels

    Directory of Open Access Journals (Sweden)

    Mike Burmester

    2017-07-01

    Full Text Available The National Strategy for Global Supply Chain Security published in 2012 by the White House identifies two primary goals for strengthening global supply chains: first, to promote the efficient and secure movement of goods, and second to foster a resilient supply chain. The Internet of Things (IoT, and in particular Radio Frequency Identification (RFID technology, can be used to realize these goals. For product identification, tracking and real-time awareness, RFID tags are attached to goods. As tagged goods move along the supply chain from the suppliers to the manufacturers, and then on to the retailers until eventually they reach the customers, two major security challenges can be identified: (I to protect the shipment of goods that are controlled by potentially untrusted carriers; and (II to secure the transfer of ownership at each stage of the chain. For the former, grouping proofs in which the tags of the scanned goods generate a proof of “simulatenous” presence can be employed, while for the latter, ownership transfer protocols (OTP are used. This paper describes enhanced security solutions for both challenges. We first extend earlier work on grouping proofs and group codes to capture resilient group scanning with untrusted readers; then, we describe a modified version of a recently published OTP based on channels with positive secrecy capacity adapted to be implemented on common RFID systems in the supply chain. The proposed solutions take into account the limitations of low cost tags employed in the supply chain, which are only required to generate pseudorandom numbers and compute one-way hash functions.

  13. An RFID-Based Smart Structure for the Supply Chain: Resilient Scanning Proofs and Ownership Transfer with Positive Secrecy Capacity Channels.

    Science.gov (United States)

    Burmester, Mike; Munilla, Jorge; Ortiz, Andrés; Caballero-Gil, Pino

    2017-07-04

    The National Strategy for Global Supply Chain Security published in 2012 by the White House identifies two primary goals for strengthening global supply chains: first, to promote the efficient and secure movement of goods, and second to foster a resilient supply chain. The Internet of Things (IoT), and in particular Radio Frequency Identification (RFID) technology, can be used to realize these goals. For product identification, tracking and real-time awareness, RFID tags are attached to goods. As tagged goods move along the supply chain from the suppliers to the manufacturers, and then on to the retailers until eventually they reach the customers, two major security challenges can be identified: (I) to protect the shipment of goods that are controlled by potentially untrusted carriers; and (II) to secure the transfer of ownership at each stage of the chain. For the former, grouping proofs in which the tags of the scanned goods generate a proof of "simulatenous" presence can be employed, while for the latter, ownership transfer protocols (OTP) are used. This paper describes enhanced security solutions for both challenges. We first extend earlier work on grouping proofs and group codes to capture resilient group scanning with untrusted readers; then, we describe a modified version of a recently published OTP based on channels with positive secrecy capacity adapted to be implemented on common RFID systems in the supply chain. The proposed solutions take into account the limitations of low cost tags employed in the supply chain, which are only required to generate pseudorandom numbers and compute one-way hash functions.

  14. Pulmonary aspergilloma: A rare differential diagnosis to lung cancer after positive FDG PET scan

    Directory of Open Access Journals (Sweden)

    Franziska Spycher

    2014-01-01

    Full Text Available Early diagnosis and treatment of lung cancer, one of the leading causes of cancer-related death, is important to improve morbidity and mortality. Therefore any suspect solitary pulmonary nodule should prompt the pursuit for a definitive histological diagnosis. We describe the case of a 55-years-old male ex-smoker, who was admitted to our hospital due to recurrent hemoptysis and dry cough. A CT scan showed an irregular nodule of increasing size (28 mm in diameter in the left lower lobe (LLL. A whole body PET-CT scan (643 MBq F-18 FDG i.v. was performed and confirmed an avid FDG uptake of the nodule in the LLL, highly suspicious of lung cancer, without any evidence of lymphogenic or hematogenic metastasis. Bronchoscopy was not diagnostic and due to severe adhesions after prior chest trauma and the central location of the nodule, a lobectomy of the LLL was performed. Surprisingly, histology showed a simple aspergilloma located in a circumscribed bronchiectasis with no evidence of malignancy. This is a report of an informative example of an aspergilloma, which presented with symptoms and radiological features of malignant lung cancer.

  15. Real-Space Analysis of Scanning Tunneling Microscopy Topography Datasets Using Sparse Modeling Approach

    Science.gov (United States)

    Miyama, Masamichi J.; Hukushima, Koji

    2018-04-01

    A sparse modeling approach is proposed for analyzing scanning tunneling microscopy topography data, which contain numerous peaks originating from the electron density of surface atoms and/or impurities. The method, based on the relevance vector machine with L1 regularization and k-means clustering, enables separation of the peaks and peak center positioning with accuracy beyond the resolution of the measurement grid. The validity and efficiency of the proposed method are demonstrated using synthetic data in comparison with the conventional least-squares method. An application of the proposed method to experimental data of a metallic oxide thin-film clearly indicates the existence of defects and corresponding local lattice distortions.

  16. Brain PET scan

    Science.gov (United States)

    ... results on a PET scan. Blood sugar or insulin levels may affect the test results in people with diabetes . PET scans may be done along with a CT scan. This combination scan is called a PET/CT. Alternative Names Brain positron emission tomography; PET scan - brain References Chernecky ...

  17. 111In-labeled nonspecific immunoglobulin scanning in the detection of focal infection

    International Nuclear Information System (INIS)

    Rubin, R.H.; Fischman, A.J.; Callahan, R.J.; Khaw, B.A.; Keech, F.; Ahmad, M.; Wilkinson, R.; Strauss, H.W.

    1989-01-01

    We performed radionuclide scanning after the intravenous injection of human IgG labeled with indium-111 in 128 patients with suspected focal sites of inflammation. Localization of 111In-labeled IgG correlated with clinical findings in 51 infected patients (21 with abdominal or pelvic infections, 11 with intravascular infections, 7 with pulmonary infections, and 12 with skeletal infections). Infecting organisms included gram-positive bacteria, gram-negative bacteria, Pneumocystis carinii, Mycoplasma pneumoniae, and Candida albicans. No focal localization of 111In-labeled IgG was observed in 63 patients without infection. There were five false negative results, and nine results were unusable. Serial scans were carried out in eight patients: continued localization correctly predicted relapse in six, and the absence of localization indicated resolution in two. To determine whether 111In-labeled IgG localization was specific for inflammation, we studied 16 patients with cancer. Focal localization occurred in 13 of these patients (5 with melanomas, 5 with gynecologic cancers, and 1 each with lymphoma, prostate cancer, and malignant fibrous histiocytoma). No localization was seen in patients with renal or colon cancer or metastatic medullary carcinoma of the thyroid. We conclude that 111In-labeled IgG imaging is effective for the detection of focal infection and that serial scans may be useful in assessing therapeutic efficacy. This technique may also be helpful in the evaluation of certain cancers

  18. Scanning reference electrode techniques in localized corrosion

    International Nuclear Information System (INIS)

    Isaacs, H.S.; Vyas, B.

    1979-04-01

    The principles, advantages, and implementations of scanning reference electrode techniques are reviewed. Data related to pitting, intergranular corrosion, welds and stress corrosion cracking are presented. The technique locates the position of localized corrosion and can be used to monitor the development of corrosion and changes in the corrosion rate under a wide range of conditions

  19. What expects orthopedic surgeon from bone scan?

    International Nuclear Information System (INIS)

    Sutter, B.; Cazenave, A.

    2003-01-01

    The isotope bone scan continues to be one of the 'lost widely performed nuclear medicine investigations. Beyond the common clinical indication like detection of skeletal metastases, bone scan use is increasing in benign orthopedic conditions, and after orthopedic surgery, despite development of new investigations modalities (US, MRI). Three (or two) phase bone scintigraphy, Single Photon Emission Computer Tomography have increased its value and provided new clinical roles. This review emphasizes through some practical clinical examples how to increase diagnostic value of the method and to offer an adapted response to the orthopedic surgeon's attempts. (author)

  20. Technetium scanning in Kaposi's sarcoma and its simulators

    International Nuclear Information System (INIS)

    Gunnoe, R.; Kalivas, J.

    1982-01-01

    The clinical picture of ulcerated purple plaques on the legs often suggests several diagnoses: Kaposi's sarcoma, stasis dermatitis, atrophie blanche (livedoid vasculitis), and a poorly understood condition called acroangiodermatitis of Favre-Chaix (pseudo-Kaposi's sarcoma). Even the skin biopsy may not always be conclusive. We describe our experience with three patients with pseudo-Kaposi's sarcoma, one with true Kaposi's sarcoma and two with atrophie blanche. Clinical and histopathologic similarities among these three conditions pointed up the need for additional confirmatory studies, i.e., isotope scanning. The technetium scan was positive in both Kaposi's sarcoma and pseudo-Kaposi's sarcoma but negative in atrophie blanche

  1. Closed-Loop Autofocus Scheme for Scanning Electron Microscope

    Directory of Open Access Journals (Sweden)

    Cui Le

    2015-01-01

    Full Text Available In this paper, we present a full scale autofocus approach for scanning electron microscope (SEM. The optimal focus (in-focus position of the microscope is achieved by maximizing the image sharpness using a vision-based closed-loop control scheme. An iterative optimization algorithm has been designed using the sharpness score derived from image gradient information. The proposed method has been implemented and validated using a tungsten gun SEM at various experimental conditions like varying raster scan speed, magnification at real-time. We demonstrate that the proposed autofocus technique is accurate, robust and fast.

  2. Implementation of dual energy CT scanning

    International Nuclear Information System (INIS)

    Marshall, W.; Hall, E.; Doost-Hoseini, A.; Alvarez, R.; Macovski, A.; Cassel, D.

    1984-01-01

    A prereconstruction method for dual energy (PREDECT) analysis of CT scans is described. In theory, this method can (a) eliminate beam hardening and produce an accuracy comparable with monoenergetic scans and (b) provide the effective atomic number and electron density of any voxel scanned. The implementation proves these statements and eliminates some of the objectionable noise. A phantom was constructed with a cylindrical sleeve-like compartment containing known amounts of high atomic number material simulating a removable skull. Conventional scans, with and without this beam hardener, were done of a water bath containing tubes of high electron and high atomic number material. Dual energy scans were then done for PREDECT. To increase the effective separation of the low and high energy beams by using more appropriate tube filtration, a beam filter changer was fabricated containing erbium, tungsten, aluminum, and steel. Erbium, tungsten, and steel were used at high energy and aluminum, steel, and erbium at low energy for data acquisition. The reconstructions were compared visually and numerically for noise levels with the original steel only filtration. A decrease was found in noise down to approximately one-half the prior level when erbium/aluminum or tungsten/aluminum replaced the steel/steel filter. Erbium and tungsten were equally effective. Steel/erbium and steel/aluminum also significantly reduced image noise. The noise in the photoelectric (P) and Compton (C) images is negatively correlated. At any pixel, if the noise is positive in the P image, it is most probably negative in the C. Using this fact, the noise was reduced by postreconstruction processing

  3. A study of respiration-correlated cone-beam CT scans to correct target positioning errors in radiotherapy of thoracic cancer

    Energy Technology Data Exchange (ETDEWEB)

    Santoro, J. P.; McNamara, J.; Yorke, E.; Pham, H.; Rimner, A.; Rosenzweig, K. E.; Mageras, G. S. [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York 10065 (United States); Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York 10065 (United States); Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York 10065 (United States)

    2012-10-15

    Purpose: There is increasingly widespread usage of cone-beam CT (CBCT) for guiding radiation treatment in advanced-stage lung tumors, but difficulties associated with daily CBCT in conventionally fractionated treatments include imaging dose to the patient, increased workload and longer treatment times. Respiration-correlated cone-beam CT (RC-CBCT) can improve localization accuracy in mobile lung tumors, but further increases the time and workload for conventionally fractionated treatments. This study investigates whether RC-CBCT-guided correction of systematic tumor deviations in standard fractionated lung tumor radiation treatments is more effective than 2D image-based correction of skeletal deviations alone. A second study goal compares respiration-correlated vs respiration-averaged images for determining tumor deviations. Methods: Eleven stage II-IV nonsmall cell lung cancer patients are enrolled in an IRB-approved prospective off-line protocol using RC-CBCT guidance to correct for systematic errors in GTV position. Patients receive a respiration-correlated planning CT (RCCT) at simulation, daily kilovoltage RC-CBCT scans during the first week of treatment and weekly scans thereafter. Four types of correction methods are compared: (1) systematic error in gross tumor volume (GTV) position, (2) systematic error in skeletal anatomy, (3) daily skeletal corrections, and (4) weekly skeletal corrections. The comparison is in terms of weighted average of the residual GTV deviations measured from the RC-CBCT scans and representing the estimated residual deviation over the treatment course. In the second study goal, GTV deviations computed from matching RCCT and RC-CBCT are compared to deviations computed from matching respiration-averaged images consisting of a CBCT reconstructed using all projections and an average-intensity-projection CT computed from the RCCT. Results: Of the eleven patients in the GTV-based systematic correction protocol, two required no correction

  4. A study of respiration-correlated cone-beam CT scans to correct target positioning errors in radiotherapy of thoracic cancer

    International Nuclear Information System (INIS)

    Santoro, J. P.; McNamara, J.; Yorke, E.; Pham, H.; Rimner, A.; Rosenzweig, K. E.; Mageras, G. S.

    2012-01-01

    Purpose: There is increasingly widespread usage of cone-beam CT (CBCT) for guiding radiation treatment in advanced-stage lung tumors, but difficulties associated with daily CBCT in conventionally fractionated treatments include imaging dose to the patient, increased workload and longer treatment times. Respiration-correlated cone-beam CT (RC-CBCT) can improve localization accuracy in mobile lung tumors, but further increases the time and workload for conventionally fractionated treatments. This study investigates whether RC-CBCT-guided correction of systematic tumor deviations in standard fractionated lung tumor radiation treatments is more effective than 2D image-based correction of skeletal deviations alone. A second study goal compares respiration-correlated vs respiration-averaged images for determining tumor deviations. Methods: Eleven stage II–IV nonsmall cell lung cancer patients are enrolled in an IRB-approved prospective off-line protocol using RC-CBCT guidance to correct for systematic errors in GTV position. Patients receive a respiration-correlated planning CT (RCCT) at simulation, daily kilovoltage RC-CBCT scans during the first week of treatment and weekly scans thereafter. Four types of correction methods are compared: (1) systematic error in gross tumor volume (GTV) position, (2) systematic error in skeletal anatomy, (3) daily skeletal corrections, and (4) weekly skeletal corrections. The comparison is in terms of weighted average of the residual GTV deviations measured from the RC-CBCT scans and representing the estimated residual deviation over the treatment course. In the second study goal, GTV deviations computed from matching RCCT and RC-CBCT are compared to deviations computed from matching respiration-averaged images consisting of a CBCT reconstructed using all projections and an average-intensity-projection CT computed from the RCCT. Results: Of the eleven patients in the GTV-based systematic correction protocol, two required no correction

  5. Positive gallium scan in the syndrome of opsoclonus-myoclonus treated with adrenocorticotropic hormone

    International Nuclear Information System (INIS)

    Gumbinas, M.; Gratz, E.S.; Johnston, G.S.; Schwartz, A.D.

    1984-01-01

    The syndrome of opsoclonus and myoclonus may be the first presenting symptom of neuroblastoma. The disorder is often controlled by treatment with adrenocorticotropic hormone (ACTH). A child with this disorder and treated with ACTH gel had abnormal uptake of 67 Ga in both adrenal glands during studies to attempt to detect an occult neuroblastoma. Repeat 67 Ga scans proved to be normal once the ACTH was discontinued and the patient was treated with prednisone. It is concluded that ACTH stimulation of normal adrenal tissue was responsible for these abnormal findings

  6. Radionuclide scanning

    International Nuclear Information System (INIS)

    Shapiro, B.

    1986-01-01

    Radionuclide scanning is the production of images of normal and diseased tissues and organs by means of the gamma-ray emissions from radiopharmaceutical agents having specific distributions in the body. The gamma rays are detected at the body surface by a variety of instruments that convert the invisible rays into visible patterns representing the distribution of the radionuclide in the body. The patterns, or images, obtained can be interpreted to provide or to aid diagnoses, to follow the course of disease, and to monitor the management of various illnesses. Scanning is a sensitive technique, but its specificity may be low when interpreted alone. To be used most successfully, radionuclide scanning must be interpreted in conjunction with other techniques, such as bone radiographs with bone scans, chest radiographs with lung scans, and ultrasonic studies with thyroid scans. Interpretation is also enhanced by providing pertinent clinical information because the distribution of radiopharmaceutical agents can be altered by drugs and by various procedures besides physiologic and pathologic conditions. Discussion of the patient with the radionuclide scanning specialist prior to the study and review of the results with that specialist after the study are beneficial

  7. Retention index of thallium-201 single photon emission computerised tomography (SPECT) as an indicator of metastasis in adenocarcinoma of the lung.

    Science.gov (United States)

    Takekawa, H.; Itoh, K.; Abe, S.; Ogura, S.; Isobe, H.; Sukou, N.; Furudate, M.; Kawakami, Y.

    1994-01-01

    We examined the relationship between the retention of thallium-201 (201Tl) on a delayed scan and the metastatic potential of adenocarcinomas of the lung. We studied 43 patients with adenocarcinoma of the lung and divided them into two groups according to the presence or absence of lymph node metastasis. 201Tl single photon emission computerised tomography (SPECT) was conducted twice: 15 min (early scan) and 120 min (delayed scan) after intravenous injection of 3 mCi of 201Tl chloride. We calculated the retention index in order to evaluate the degree of 201Tl retention in the primary tumour. The retention indices were significantly higher in the group that was positive for lymph node metastasis than in the negative group. In adenocarcinomas with high metastatic potential, 201Tl SPECT demonstrated slow washout or increased retention on the delayed scan. The retention index of 201Tl SPECT is a useful indicator of metastatic potential, thereby facilitating the prediction of prognosis, and provides insight into the relationship between 201Tl uptake and malignancy. This is the first report demonstrating a significant relationship between the retention of 201Tl SPECT and lymph node metastasis. Images Figure 1 PMID:8054281

  8. Computed tomography scan in supine and prone positions: an alternative method to detect intramural gas in emphysematous cystitis and to evaluate efficacy after adjuvant continuous intravesical irrigation treatment.

    Science.gov (United States)

    Cortés-González, Jeff R; Ortiz-Lara, Gerardo E; Salinas, Matías; Hernández-Galván, Fernando; Gómez-Guerra, Lauro S

    2013-04-01

    To evaluate the efficacy of continuous intravesical irrigation with saline plus amikacin as adjuvant therapy and to evaluate the computed tomography (CT) scan in supine and prone positions (CystoCT scan) as an alternative diagnostic and evaluation method of intramural gas in emphysematous cystitis (EC) before and after treatment. Consecutive patients with a diagnosis of EC who were hospitalized between March 2006 and January 2011 were investigated. The diagnosis was made by CystoCT scan. Treatment consisted of intravenous antibiotics, control of concomitant diseases, and placement of a 3-way urinary catheter for continuous irrigation of 500 mg of amikacin diluted in 1 l of saline given on days 0, 3, and 7. Treatment was considered successful when there was an absence of gas in the bladder wall, the urine culture was negative, there was clinical improvement, and there was an absence of toxicity. Eleven patients were hospitalized with a diagnosis of EC during the study period. Four were excluded from the study, 2 due to the lack of confirmation of the diagnosis with the CystoCT scan. Treatment was successful in all patients; for 6 (86%) this was achieved in 3 days and for 1 (14%) in 7 days. No toxicity was reported. Continuous intravesical irrigation with saline plus amikacin as adjuvant treatment of EC is an inexpensive, effective, and safe tool that might help conventional treatment and provide a rapid recovery. The CystoCT scan is an alternative method to diagnose and evaluate intramural gas in EC patients. These findings should be challenged in a randomized, multi-centre, placebo-controlled clinical trial.

  9. Influence of Lymphatic Invasion on Locoregional Recurrence Following Mastectomy: Indication for Postmastectomy Radiotherapy for Breast Cancer Patients With One to Three Positive Nodes

    International Nuclear Information System (INIS)

    Matsunuma, Ryoichi; Oguchi, Masahiko; Fujikane, Tomoko; Matsuura, Masaaki; Sakai, Takehiko; Kimura, Kiyomi; Morizono, Hidetomo; Iijima, Kotaro; Izumori, Ayumi; Miyagi, Yumi; Nishimura, Seiichiro; Makita, Masujiro; Gomi, Naoya; Horii, Rie; Akiyama, Futoshi; Iwase, Takuji

    2012-01-01

    Purpose: The indication for postmastectomy radiotherapy (PMRT) in breast cancer patients with one to three positive lymph nodes has been in discussion. The purpose of this study was to identify patient groups for whom PMRT may be indicated, focusing on varied locoregional recurrence rates depending on lymphatic invasion (ly) status. Methods and Materials: Retrospective analysis of 1,994 node-positive patients who had undergone mastectomy without postoperative radiotherapy between January 1990 and December 2000 at our hospital was performed. Patient groups for whom PMRT should be indicated were assessed using statistical tests based on the relationship between locoregional recurrence rate and ly status. Results: Multivariate analysis showed that the ly status affected the locoregional recurrence rate to as great a degree as the number of positive lymph nodes (p < 0.001). Especially for patients with one to three positive nodes, extensive ly was a more significant factor than stage T3 in the TNM staging system for locoregional recurrence (p < 0.001 vs. p = 0.295). Conclusion: Among postmastectomy patients with one to three positive lymph nodes, patients with extensive ly seem to require local therapy regimens similar to those used for patients with four or more positive nodes and also seem to require consideration of the use of PMRT.

  10. Bone metastases from breast cancer at the time or radical mastectomy as detected by bone scan. Eight-year follow-up.

    Science.gov (United States)

    Sklaroff, R B; Sklaroff, D M

    1976-07-01

    Sixty-four women with Stage II breast cancer who had Sr85 bone scans at the time of radical mastectomy were followed for 8 years in a prospective study. Those women with positive scans had a slight, but statistically significant, increased incidence of metastic disease, particularly for metastases to bone.However, 40% of those women with positive bone scans and negative roentgenograms survived 8 years without evidence of any metastatic disease. Therefore, it has not been shown at this time that bone scans should be obtained in order to exclude bone metastasis before regional therapy for breast cancer is instituted. Also, a significant percentage of women with negative bone scans developed both bone and soft tissue metastases. As many as 30% of asymptomatic women with a history of breast cancer and positive bone scans and negative bone roentgenograms may still harbor disease in bone after 8 years.

  11. Method and apparatus for a high-resolution three dimensional confocal scanning transmission electron microscope

    Science.gov (United States)

    de Jonge, Niels [Oak Ridge, TN

    2010-08-17

    A confocal scanning transmission electron microscope which includes an electron illumination device providing an incident electron beam propagating in a direction defining a propagation axis, and a precision specimen scanning stage positioned along the propagation axis and movable in at least one direction transverse to the propagation axis. The precision specimen scanning stage is configured for positioning a specimen relative to the incident electron beam. A projector lens receives a transmitted electron beam transmitted through at least part of the specimen and focuses this transmitted beam onto an image plane, where the transmitted beam results from the specimen being illuminated by the incident electron beam. A detection system is placed approximately in the image plane.

  12. A scan for positively selected genes in the genomes of humans and chimpanzees.

    Directory of Open Access Journals (Sweden)

    Rasmus Nielsen

    2005-06-01

    Full Text Available Since the divergence of humans and chimpanzees about 5 million years ago, these species have undergone a remarkable evolution with drastic divergence in anatomy and cognitive abilities. At the molecular level, despite the small overall magnitude of DNA sequence divergence, we might expect such evolutionary changes to leave a noticeable signature throughout the genome. We here compare 13,731 annotated genes from humans to their chimpanzee orthologs to identify genes that show evidence of positive selection. Many of the genes that present a signature of positive selection tend to be involved in sensory perception or immune defenses. However, the group of genes that show the strongest evidence for positive selection also includes a surprising number of genes involved in tumor suppression and apoptosis, and of genes involved in spermatogenesis. We hypothesize that positive selection in some of these genes may be driven by genomic conflict due to apoptosis during spermatogenesis. Genes with maximal expression in the brain show little or no evidence for positive selection, while genes with maximal expression in the testis tend to be enriched with positively selected genes. Genes on the X chromosome also tend to show an elevated tendency for positive selection. We also present polymorphism data from 20 Caucasian Americans and 19 African Americans for the 50 annotated genes showing the strongest evidence for positive selection. The polymorphism analysis further supports the presence of positive selection in these genes by showing an excess of high-frequency derived nonsynonymous mutations.

  13. Xenon ventilation-perfusion lung scans. The early diagnosis of inhalation injury

    International Nuclear Information System (INIS)

    Schall, G.L.; McDonald, H.D.; Carr, L.B.; Capozzi, A.

    1978-01-01

    The use of xenon Xe-133 ventilation-perfusion lung scans for the early diagnosis of inhalation injury was evaluated in 67 patients with acute thermal burns. Study results were interpreted as normal if there was complete pulmonary clearance of the radioactive gas by 150 seconds. Thirty-two scans were normal, 32 abnormal, and three technically inadequate. There were three true false-positive study results and one false-negative study result. Good correlation was found between the scan results and various historical, physical, and laboratory values currently used to evaluate inhalation injury. The scans appeared to be the most sensitive method for the detection of early involvement, often being abnormal several days before the chest roentgenogram. Xenon lung scanning is a safe, easy, accurate, and sensitive method for the early diagnosis of inhalation injury and has important therapeutic and prognostic implications as well

  14. Comparative Functional Alanine Positional Scanning of the α-Melanocyte Stimulating Hormone and NDP-Melanocyte Stimulating Hormone Demonstrates Differential Structure-Activity Relationships at the Mouse Melanocortin Receptors.

    Science.gov (United States)

    Todorovic, Aleksandar; Ericson, Mark D; Palusak, Ryan D; Sorensen, Nicholas B; Wood, Michael S; Xiang, Zhimin; Haskell-Luevano, Carrie

    2016-07-20

    The melanocortin system has been implicated in the regulation of various physiological functions including melanogenesis, steroidogenesis, energy homeostasis, and feeding behavior. Five melanocortin receptors have been identified to date and belong to the family of G protein-coupled receptors (GPCR). Post-translational modification of the proopiomelanocortin (POMC) prohormone leads to the biosynthesis of the endogenous melanocortin agonists, including α-melanocyte stimulating hormone (α-MSH), β-MSH, γ-MSH, and adrenocorticotropic hormone (ACTH). All the melanocortin agonists derived from the POMC prohormone contain a His-Phe-Arg-Trp tetrapeptide sequence that has been implicated in eliciting the pharmacological responses at the melanocortin receptors. Herein, an alanine (Ala) positional scan is reported for the endogenous α-MSH ligand and the synthetic, more potent, NDP-MSH peptide (Ac-Ser(1)-Tyr(2)-Ser(3)-Nle(4)-Glu(5)-His(6)-DPhe(7)-Arg(8)-Trp(9)-Gly(10)-Lys(11)-Pro(12)-Val(13)-NH2) at the cloned mouse melanocortin receptors to test the assumption that the structure-activity relationships of one ligand would apply to the other. Several residues outside of the postulated pharmacophore altered potency at the melanocortin receptors, most notably the 1560-, 37-, and 15-fold potency loss when the Glu(5) position of α-MSH was substituted with Ala at the mMC1R, mMC3R, and mMC4R, respectively. Importantly, the altered potencies due to Ala substitutions in α-MSH did not necessarily correlate with equivalent Ala substitutions in NDP-MSH, indicating that structural modifications and corresponding biological activities in one of these melanocortin ligands may not be predictive for the other agonist.

  15. Value of hepatobiliary scanning in complex liver trauma

    International Nuclear Information System (INIS)

    Gartman, D.M.; Zeman, R.K.; Cahow, C.E.; Baker, C.C.

    1985-01-01

    To evaluate the use of biliary scintigraphy with /sup 99m/Tc-dimethyl analogs (HIDA) in traumatic liver injuries, a group of 26 patients with penetrating and blunt liver injuries were studied. The results indicate that HIDA scanning is an effective noninvasive method of evaluating the hepatobiliary tree in the post-traumatic setting. The HIDA scan is a sensitive tool for studying the hepatic parenchyma and the presence or absence of bile leaks. Its evaluation of the extrahepatic biliary ductal system is not specific and should be assessed with further studies. Gallbladder nonvisualization by HIDA scans in this setting cannot be presumed to be secondary to acute cholecystitis and should be interpreted with extreme caution

  16. Optimal scanning and image processing with the STEM

    International Nuclear Information System (INIS)

    Crewe, A.V.; Ohtsuki, M.

    1981-01-01

    We have recently published a theory of an optimal scanning system which is particularly suited for the STEM. One concludes from the theory that the diffraction limit of the electron probe should be a fixed fraction of the full-scale deflection in order to avoid scanning artifacts. More recently, we have confirmed the value of this technique by direct experiments. Our program now is to combine the use of optimal scanning with the use of a programmable digital refresh memory for image analysis. Limited experience to date indicates that false color conversion is probably more useful than histogram equalization in black and white and that this system is particularly valuable for rotational averaging and selected area Fourier transforms. (orig.)

  17. A cause of false positive of the whole body scanning with iodine 131: obstructive hydronephrosis; Une cause de faux-positif du balayage corps entier a l'iode 131: l'hydronephrose obstructive

    Energy Technology Data Exchange (ETDEWEB)

    Sellem, A.; Elbez, I.; Rejeb, O.; Elkadri, N.; Hammami, H. [Service de medecine nucleaire, hopital Militaire, Tunis, (Tunisia)

    2009-05-15

    The objective is to report the case of a differentiated carcinoma of the thyroid with a false positive aspect to the whole-body scanning with iodine 131 in relation with an accumulation of the tracer at the level of an obstructive appearance hydronephrosis. (N.C.)

  18. Simultaneous emission and transmission scanning in positron emission tomography

    International Nuclear Information System (INIS)

    Satoh, Tomohiko; Tanaka, Kazumi; Kitamura, Keishi; Amano, Masaharu; Miura, Shuichi

    2001-01-01

    Examination by PET (positron emission tomography) scanning, following the dosage of 2-deoxy- 18 F fluoro-D-glucose (FDG), is positively utilized for the diagnosis of cancers, rather than for the purpose of studies. This is because the examination by FDG-PET (PET scanning following the dosage of FDG) ensures higher efficiency in discrimination of cancers, than conventional CT and PET. The method of whole body scanning by PET scanning following the dosage of FDG is effectively utilized not only for discrimination cancers, but also for determining the degree of malignancy of tumors and evaluating the methods of treatment of cancers. In conventional methods for examining the degree of malignancy of tumors and evaluating the methods of cancer treatment, it is necessary to correct for the gamma-ray attenuation, which requires a longer time for examination, increasing the physical and psychological pains of the patients. We have installed the simultaneous emission and transmission scanning capability into the HEADTOME-V of the Shimadzu SET-2000W Series positron emission tomographic scanning instruments, to establish an instrument that permits FDG-PET whole body scanning in actual clinical fields, with minimized physical and psychological pains of patients concerned, yet ensuring an outstandingly high examination efficiency. This report also presents some data obtained by this newly developed instrument and those obtained in practical applications. (author)

  19. Combined use of fine-needle aspiration biopsy, MIBI scans and frozen section biopsy offers the best diagnostic accuracy in the assessment of the hypofunctioning solitary thyroid nodule

    International Nuclear Information System (INIS)

    Hurtado-Lopez, Luis Mauricio; Arellano-Montano, Sara; Torres-Acosta, Evelyn Migdalia; Zaldivar-Ramirez, Felipe Rafael; Duarte-Torres, Reyna Margarita; Alonso-de-Ruiz, Patricia; Martinez-Duncker, Ivan; Martinez-Duncker, Carlos

    2004-01-01

    The probability of malignancy is increased in hypofunctioning solitary thyroid nodules (HFNs). Fine-needle aspiration biopsy (FNA), 99m Tc-methoxyisobutylisonitrile (MIBI) and frozen section biopsy (FS) have limited independent diagnostic accuracy for the differential diagnosis of HFNs. The goal of this study was to assess the accuracy of the three independent diagnostic methods in distinguishing between benign and malignant disease. A total of 130 patients with an HFN on the 99m Tc-pertechnetate scan were included in this study. FNA, MIBI scans, FS, thyroidectomy and histological analysis of surgical specimens for final diagnosis were performed in all patients. Of the 130 patients, 80 (61.54%) had benign lesions and 50 (38.46%), malignant lesions. FNA was diagnostic in 78/130 (60%) patients and non-diagnostic in 52/130 (40%) patients. None of the patients with a negative MIBI scan had a final histological diagnosis of malignancy, and MIBI scans were negative in 38.46% of patients with non-diagnostic FNA results. FS was diagnostic in 104/130 (80%) patients and non-diagnostic in 26/130 (20%) patients. Sensitivity, specificity, positive and negative predictive values and positive and negative likelihood ratios were 81.3%, 97.8%, 96%, 88%, 36.95 and 0.19 respectively for FNA; 100%, 61.3%, 61.7%, 100%, 2.58 and 0 respectively for MIBI; and 80.5%, 100%, 100%, 89%, 0 and 0.2 respectively for FS. Use of both MIBI scans and FS in patients with non-diagnostic FNA rendered a specificity and sensitivity of 100%. MIBI scans exclude malignancy in a significant proportion of patients with non-diagnostic FNAs (38% in this study). Cystic nodules with a positive MIBI scan should be further investigated even when the FNA result indicates a benign lesion. Combined use of FNA, MIBI and FS offers the best diagnostic accuracy. (orig.)

  20. Diagnosis of gynecologic pelvic masses by CT scans

    International Nuclear Information System (INIS)

    Ito, Hisao; Kubo, Atsushi; Takagi, Yaeko; Kinoshita, Fumio; Maekawa, Akira.

    1981-01-01

    Two hundred eighty four patients with gynecologic pelvic masses were evaluated with CT scans. Of the patients, 196 had subsequent surgical determination of abnormalities and pathological proof of diagnosis was obtained. Only these 196 patients were included in this study. The CT scans could provide correct diagnosis in 113 of 114 (99%) patients with benign uterine tumor and in all (100%) patients with either serous cystadenoma or dermoid cyst. However, evaluation of mucinous cystadenoma (44%) and endometriosis cyst (37%) by CT scan has some limitations. It was difficult to differentiate mucinous cystadenoma from ovarian carcinoma, because both lesions had partial multiloculation and solid-like areas in the cyst. The CT findings of endometriosis cyst had similarity with serous cystadenoma, and 5 of 8 patients with this disease were diagnosed as serous cystadenoma. Ovarian fibroma and endometrial cancer were also not determined by CT scans. CT identified 87% of patients with ovarian cancer, while false positive rate of this disease was 38% (8/21). In 6 of 13 patients with both of leiomyoma and ovarian cyst, CT was able to demonstrate ovarian lesions that were overlooked by bimanual examinations. The role of CT scanning in our clinical practice is discussed. (author)

  1. prokaryote genome annotation with GeneScan and GLIMMER

    Indian Academy of Sciences (India)

    Unknown

    The number of false predictions (both positive and negative) is higher for GeneScan as compared to GLIMMER, but in a ... on whether they need to be trained on a set of genes in order to ..... FP has partial matches to the kdpA gene in C. jejuni.

  2. Reconstruction of a time-averaged midposition CT scan for radiotherapy planning of lung cancer patients using deformable registration

    International Nuclear Information System (INIS)

    Wolthaus, J. W. H.; Sonke, J.-J.; Herk, M. van; Damen, E. M. F.

    2008-01-01

    Purpose: lower lobe lung tumors move with amplitudes of up to 2 cm due to respiration. To reduce respiration imaging artifacts in planning CT scans, 4D imaging techniques are used. Currently, we use a single (midventilation) frame of the 4D data set for clinical delineation of structures and radiotherapy planning. A single frame, however, often contains artifacts due to breathing irregularities, and is noisier than a conventional CT scan since the exposure per frame is lower. Moreover, the tumor may be displaced from the mean tumor position due to hysteresis. The aim of this work is to develop a framework for the acquisition of a good quality scan representing all scanned anatomy in the mean position by averaging transformed (deformed) CT frames, i.e., canceling out motion. A nonrigid registration method is necessary since motion varies over the lung. Methods and Materials: 4D and inspiration breath-hold (BH) CT scans were acquired for 13 patients. An iterative multiscale motion estimation technique was applied to the 4D CT scan, similar to optical flow but using image phase (gray-value transitions from bright to dark and vice versa) instead. From the (4D) deformation vector field (DVF) derived, the local mean position in the respiratory cycle was computed and the 4D DVF was modified to deform all structures of the original 4D CT scan to this mean position. A 3D midposition (MidP) CT scan was then obtained by (arithmetic or median) averaging of the deformed 4D CT scan. Image registration accuracy, tumor shape deviation with respect to the BH CT scan, and noise were determined to evaluate the image fidelity of the MidP CT scan and the performance of the technique. Results: Accuracy of the used deformable image registration method was comparable to established automated locally rigid registration and to manual landmark registration (average difference to both methods <0.5 mm for all directions) for the tumor region. From visual assessment, the registration was good

  3. Intraoral 3D Scanning or Dental Impressions for the Assessment of Dental Arch Relationships in Cleft Care: Which is Superior?

    Science.gov (United States)

    Chalmers, E V; McIntyre, G T; Wang, W; Gillgrass, T; Martin, C B; Mossey, P A

    2016-09-01

    This study was undertaken to evaluate intraoral 3D scans for assessing dental arch relationships and obtain patient/parent perceptions of impressions and intraoral 3D scanning. Forty-three subjects with nonsyndromic unilateral cleft lip and palate (UCLP) had impressions taken for plaster models. These and the teeth were scanned using the R700 Orthodontic Study Model Scanner and Trios® Digital Impressions Scanner (3Shape A/S, Copenhagen, Denmark) to create indirect and direct digital models. All model formats were scored by three observers on two occasions using the GOSLON and modified Huddart Bodenham (MHB) indices. Participants and parents scored their perceptions of impressions and scanning from 1 (very good) to 5 (very bad). Intra- and interexaminer reliability were tested using GOSLON and MHB data (Cronbach's Alpha >0.9). Bland and Altman plots were created for MHB data, with each model medium (one-sample t tests, P 0.9) were good for all formats with the direct digital models having the lowest interexaminer differences. Participants had higher ratings for scanning comfort (84.8%) than impressions (44.2%) (P impressions (51.2%) (P > .05). None disliked scanning, but 16.3% disliked impressions. Data for parents and children positively correlated (P 3D scans was superior to indirect digital and to plaster models; Subjects with UCLP preferred intra-oral 3D scanning to dental impressions, mirrored by parents/carers; This study supports the replacement of conventional impressions with intra-oral 3D scans in longitudinal evaluations of the outcomes of cleft care.

  4. Safe Active Scanning for Energy Delivery Systems Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Helms, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Salazar, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Scheibel, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Engels, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reiger, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-30

    The Department of Energy’s Cybersecurity for Energy Delivery Systems Program has funded Safe(r) Active Scanning for Energy Delivery Systems, led by Lawrence Livermore National Laboratory, to investigate and analyze the impacts of active scanning in the operational environment of energy delivery systems. In collaboration with Pacific Northwest National Laboratory and Idaho National Laboratory, active scans across three testbeds including 38 devices were performed. This report gives a summary of the initial literature survey performed on the SASEDS project as well as industry partner interview summaries and main findings from Phase 1 of the project. Additionally, the report goes into the details of scanning techniques, methodologies for testing, testbed descriptions, and scanning results, with appendices to elaborate on the specific scans that were performed. As a result of testing, a single device out of 38 exhibited problems when actively scanned, and a reboot was required to fix it. This single failure indicates that active scanning is not likely to have a detrimental effect on the safety and resilience of energy delivery systems. We provide a path forward for future research that could enable wide adoption of active scanning and lead utilities to incorporate active scanning as part of their default network security plans to discover and rectify rogue devices, adversaries, and services that may be on the network. This increased network visibility will allow operational technology cybersecurity practitioners to improve their situational awareness of networks and their vulnerabilities.

  5. Three-dimensional scanning force/tunneling spectroscopy at room temperature

    International Nuclear Information System (INIS)

    Sugimoto, Yoshiaki; Ueda, Keiichi; Abe, Masayuki; Morita, Seizo

    2012-01-01

    We simultaneously measured the force and tunneling current in three-dimensional (3D) space on the Si(111)-(7 × 7) surface using scanning force/tunneling microscopy at room temperature. The observables, the frequency shift and the time-averaged tunneling current were converted to the physical quantities of interest, i.e. the interaction force and the instantaneous tunneling current. Using the same tip, the local density of states (LDOS) was mapped on the same surface area at constant height by measuring the time-averaged tunneling current as a function of the bias voltage at every lateral position. LDOS images at negative sample voltages indicate that the tip apex is covered with Si atoms, which is consistent with the Si-Si covalent bonding mechanism for AFM imaging. A measurement technique for 3D force/current mapping and LDOS imaging on the equivalent surface area using the same tip was thus demonstrated. (paper)

  6. Three phase bone scan in sports injuries

    International Nuclear Information System (INIS)

    Chauhan, M.S.; Chowhan, M.

    2007-01-01

    Full text: Sports injuries are common in individual who participate in sports and exercise related activities. In majority of sports related injuries such as stress fracture, periosteitits, acute stress reaction of bone, the radiological investigations are usually normal in early stages. These injuries can lead to serious complications if not detected early and managed properly. This study was jointly carried out in premier medical institutes. All patients were referred from premier sports institute of the country and also by orthopedic surgeons. All patients were subjected for relevant radiological investigations and 3 phase bone scan. Total number of cases included in this study was 70 (N=70) among which bone scan was positive for stress fracture in 45 patients and shin splint was detected in 15 patients and avulsion injury seen in 3 patients. However, only one patient showed features of avulsion injury in X ray and in 1 patient X-ray was inconclusive. Conclusion:-The study shows that 3 phase bone scan is the most sensitive and relatively an inexpensive study. Bone scan has the ability for early detection of sports injuries and provide physiological information and evaluate multiple sites in single examination.SPECT study will help in the diagnostic specificity. (author)

  7. The scanning Compton polarimeter for the SLD experiment

    International Nuclear Information System (INIS)

    Woods, M.

    1996-10-01

    For the 1994/95 run of the SLD experiment at SLAC, a Compton polarimeter measured the luminosity-weighted electron beam polarization to be (77.2 ± 0.5)%. This excellent accuracy is achieved by measuring the rate asymmetry of Compton-scattered electrons near the kinematic endpoint. The polarimeter takes data continuously while the electron and positron beams are in collision and achieves a statistical precision of better than 1% in a three minute run. To calibrate the polarimeter and demonstrate its accuracy, many scans are frequently done. These include scans of the laser polarization, the detector position with respect to the kinematic edge, and the laser power

  8. Scanning gate microscopy on graphene: charge inhomogeneity and extrinsic doping

    International Nuclear Information System (INIS)

    Jalilian, Romaneh; Tian Jifa; Chen, Yong P; Jauregui, Luis A; Lopez, Gabriel; Roecker, Caleb; Jovanovic, Igor; Yazdanpanah, Mehdi M; Cohn, Robert W

    2011-01-01

    We have performed scanning gate microscopy (SGM) on graphene field effect transistors (GFET) using a biased metallic nanowire coated with a dielectric layer as a contact mode tip and local top gate. Electrical transport through graphene at various back gate voltages is monitored as a function of tip voltage and tip position. Near the Dirac point, the response of graphene resistance to the tip voltage shows significant variation with tip position, and SGM imaging displays mesoscopic domains of electron-doped and hole-doped regions. Our measurements reveal substantial spatial fluctuation in the carrier density in graphene due to extrinsic local doping from sources such as metal contacts, graphene edges, structural defects and resist residues. Our scanning gate measurements also demonstrate graphene's excellent capability to sense the local electric field and charges.

  9. Digital Position Encoding Of Galvanometer Scanner In A Laser Microscope

    Science.gov (United States)

    Liljeborg, Anders

    1988-09-01

    An account is given of a realization of a feedback method to digitize the analog position signal from a moving iron galvanometer. It is employed in a confocal scanning laser microscope for generating digital images. The photometric sampling has to be closely coupled to the position of a mirror that scans a focused laser beam across a microscope specimen. Pictures with low geometric distortion are obtained up to the size 1024 x 1024 pixels.

  10. Scanning Emitter Lifetime Imaging Microscopy for Spontaneous Emission Control

    DEFF Research Database (Denmark)

    Frimmer, Martin; Chen, Yuntian; Koenderink, A. Femius

    2011-01-01

    We report an experimental technique to map and exploit the local density of optical states of arbitrary planar nanophotonic structures. The method relies on positioning a spontaneous emitter attached to a scanning probe deterministically and reversibly with respect to its photonic environment while...

  11. Contribution of brain imaging techniques: CT-scan and magnetic resonance imaging (MRI)

    International Nuclear Information System (INIS)

    Pasco-Papon, A.; Gourdier, A.L.; Papon, X.; Caron-Poitreau, C.

    1996-01-01

    In light of the current lack of consensus on the benefit of carotid artery surgery to treat asymptomatic carotid artery stenosis, the decision to operate on a patient depends on individual evaluation and characterization of risk factors on carotid artery stenosis greater than 70 %. The assessment of such risk factors is based especially on non-invasive brain imaging techniques.Computed tomography scanning (CT-scan) and magnetic resonance imaging (MRI) enable two types of stenosis to be differentiated, i.e. stenoses which are symptomatic and those that are radiologically proven versus those which are clinically and radiologically silent. CT-scan investigation (with and without injection of iodinated contrast media) still continues to be a common routine test in 1996 whenever a surgical revascularization procedure is planned. The presence of deep lacunar infarcts ipsilateral to the carotid artery stenosis generally evidence the reality of stenosis and thus are useful to the surgeon in establishing whether surgery is indicated. In the absence a consensus on indications for surgical management, the surgeon could use the CT-scan and MRI as medicolegal records which could be compared to a subsequent postoperative CT-scan in case of ischemic complications associated with the surgical procedure. Furthermore, recent cerebral ischemia as evidenced by filling with contrast material, will call for postponing treatment by a few weeks. Although conventional MRI is more contributive than brain CT-scan in terms of sensibility and specificity, its indications are narrower because of its limited availability and cost constraints. But, development of angio-MRI and functional imaging promise that its future is assured and even perhaps as the sole diagnostic method if its indications are expanded to include preoperative angiographic evaluation of atheromatous lesions of supra-aortic trunks. (authors). 37 refs

  12. Liver scanning with sup(99m)Tc-phytate

    Energy Technology Data Exchange (ETDEWEB)

    Kubo, A; Isobe, Y; Kobayashi, T; (Keio Univ., Tokyo (Japan). School of Medicine); Kinoshita, Fumio; Shibata, Masayoshi

    1975-03-01

    /sup 198/Au-colloid has been widely used for liver scanning in Japan but it is not the best scanning agent because of the large exposure dose to the patient. The authors performed a few basic experiments with sup(99m)Tc-phytate, the preparation of which is very easy. The labeling efficiency was found to be 97.5% immediately after preparation and it remained fairly stable for a period of time. As a result, the compound can be used up to 6 hours after preparation without fear of chemical instability. Liver scanning with sup(99m)Tc-phytate was done on 116 patients and was compared with /sup 198/Au-colloid liver-scanning. Scans made with sup(99m)Tc were found to be superior to those made with /sup 198/Au in the resolution of surface defects in the liver, while at increasing depths the resolution with sup(99m)Tc dropped rapidly, apparently due to absorption of its relatively low energy photon. This indicates the importance of taking multidirectional views. The degrees of splenic concentration of sup(99m)Tc-phytate were fairly close to those of /sup 198/Au-colloid. Therefore, liver scanning with sup(99m)Tc-phytate is useful in the diagnostic evaluation of diffuse parenchymal liver disease.

  13. Liver scanning with sup(99m)Tc-phytate

    International Nuclear Information System (INIS)

    Kubo, Atsushi; Isobe, Yoshinori; Kobayashi, Takeshi; Kinoshita, Fumio; Shibata, Masayoshi.

    1975-01-01

    198 Au-colloid has been widely used for liver scanning in Japan but it is not the best scanning agent because of the large exposure dose to the patient. The authors performed a few basic experiments with sup(99m)Tc-phytate, the preparation of which is very easy. The labeling efficiency was found to be 97.5% immediately after preparation and it remained fairly stable for a period of time. As a result, the compound can be used up to 6 hours after preparation without fear of chemical instability. Liver scanning with sup(99m)Tc-phytate was done on 116 patients and was compared with 198 Au-colloid liver-scanning. Scans made with sup(99m)Tc were found to be superior to those made with 198 Au in the resolution of surface defects in the liver, while at increasing depths the resolution with sup(99m)Tc dropped rapidly, apparently due to absorption of its relatively low energy photon. This indicates the importance of taking multidirectional views. The degrees of splenic concentration of sup(99m)Tc-phytate were fairly close to those of 198 Au-colloid. Therefore, liver scanning with sup(99m)Tc-phytate is useful in the diagnostic evaluation of diffuse parenchymal liver disease. (auth.)

  14. Controlling molecular condensation/diffusion of copper phthalocyanine by local electric field induced with scanning tunneling microscope tip

    Science.gov (United States)

    Nagaoka, Katsumi; Yaginuma, Shin; Nakayama, Tomonobu

    2018-02-01

    We have discovered the condensation/diffusion phenomena of copper phthalocyanine (CuPc) molecules controlled with a pulsed electric field induced by the scanning tunneling microscope tip. This behavior is not explained by the conventional induced dipole model. In order to understand the mechanism, we have measured the electronic structure of the molecule by tunneling spectroscopy and also performed theoretical calculations on molecular orbitals. These data clearly indicate that the molecule is positively charged owing to charge transfer to the substrate, and that hydrogen bonding exists between CuPc molecules, which makes the molecular island stable.

  15. Patterns of positive selection in six Mammalian genomes

    DEFF Research Database (Denmark)

    Kosiol, Carolin; Vinar, Tomás; da Fonseca, Rute R

    2008-01-01

    Genome-wide scans for positively selected genes (PSGs) in mammals have provided insight into the dynamics of genome evolution, the genetic basis of differences between species, and the functions of individual genes. However, previous scans have been limited in power and accuracy owing to small...... several new lineage- and clade-specific tests to be applied. Of approximately 16,500 human genes with high-confidence orthologs in at least two other species, 400 genes showed significant evidence of positive selection (FDR... showed evidence of positive selection on particular lineages or clades. As in previous studies, the identified PSGs were enriched for roles in defense/immunity, chemosensory perception, and reproduction, but enrichments were also evident for more specific functions, such as complement-mediated immunity...

  16. Association between red blood cell indices and CD4 count in HIV-positive reproductive women

    Science.gov (United States)

    Lumbanraja, S. N.; Siregar, D. I. S.

    2018-03-01

    Red blood cell indices, hemoglobin, and hematocrit reflect rapidity of HIV disease progression. This study aims to determine red blood cell indices and CD4 count in HIV-positive reproductive women. This study was a cross sectional study conducted at AIDS outpatient clinic at Haji Adam Malik General Hospital, Medan Indonesia. All seropositive reproductive women within antiretroviral therapy consented for blood count and CD4 examination. Data were collected and analyzed with SPSS 19. In subjects with CD4≤350 mm3, mean hemoglobin was 10.95 ± 2.01, hematocrit was 31.83 ± 5.04%, MCV was 84.17 ± 11.41, MCH was 25.98 ± 2.65, and MCHC was 32.18 ± 2.17. Mean hemoglobin, hematocrit, and MCH value was significantly lower in subjects with CD4 ≤350 mm3 (p=0.014; p=0.001; p=0.01; respectively). Lower Hb, Ht, and MCH associated with thelower CD4 count.

  17. An RFID-Based Smart Structure for the Supply Chain: Resilient Scanning Proofs and Ownership Transfer with Positive Secrecy Capacity Channels †

    Science.gov (United States)

    Ortiz, Andrés

    2017-01-01

    The National Strategy for Global Supply Chain Security published in 2012 by the White House identifies two primary goals for strengthening global supply chains: first, to promote the efficient and secure movement of goods, and second to foster a resilient supply chain. The Internet of Things (IoT), and in particular Radio Frequency Identification (RFID) technology, can be used to realize these goals. For product identification, tracking and real-time awareness, RFID tags are attached to goods. As tagged goods move along the supply chain from the suppliers to the manufacturers, and then on to the retailers until eventually they reach the customers, two major security challenges can be identified: (I) to protect the shipment of goods that are controlled by potentially untrusted carriers; and (II) to secure the transfer of ownership at each stage of the chain. For the former, grouping proofs in which the tags of the scanned goods generate a proof of “simulatenous” presence can be employed, while for the latter, ownership transfer protocols (OTP) are used. This paper describes enhanced security solutions for both challenges. We first extend earlier work on grouping proofs and group codes to capture resilient group scanning with untrusted readers; then, we describe a modified version of a recently published OTP based on channels with positive secrecy capacity adapted to be implemented on common RFID systems in the supply chain. The proposed solutions take into account the limitations of low cost tags employed in the supply chain, which are only required to generate pseudorandom numbers and compute one-way hash functions. PMID:28677637

  18. Geographic analysis of forest health indicators using spatial scan statistics

    Science.gov (United States)

    John W. Coulston; Kurt H. Riitters

    2003-01-01

    Forest health analysts seek to define the location, extent, and magnitude of changes in forest ecosystems, to explain the observed changes when possible, and to draw attention to the unexplained changes for further investigation. The data come from a variety of sources including satellite images, field plot measurements, and low-altitude aerial surveys. Indicators...

  19. {sup 11}C-Choline PET/CT for restaging prostate cancer. Results from 4,426 scans in a single-centre patient series

    Energy Technology Data Exchange (ETDEWEB)

    Graziani, Tiziano; Ceci, Francesco; Polverari, Giulia; Lima, Giacomo Maria; Lodi, Filippo; Fanti, Stefano [S. Orsola-Malpighi Hospital, University of Bologna, Service of Nuclear Medicine, Bologna (Italy); Castellucci, Paolo [S. Orsola-Malpighi Hospital, University of Bologna, Service of Nuclear Medicine, Bologna (Italy); Azienda Ospedaliero-Universitaria di Bologna, Policlinico S. Orsola-Malpighi, UO Medicina Nucleare, Bologna (Italy); Morganti, Alessio Giuseppe [S. Orsola-Malpighi Hospital, University of Bologna, Department of Radiotherapy, Bologna (Italy); Ardizzoni, Andrea [S. Orsola-Malpighi Hospital, University of Bologna, Department of Oncology, Bologna (Italy); Schiavina, Riccardo [S. Orsola-Malpighi Hospital, University of Bologna, Department of Urology, Bologna (Italy)

    2016-10-15

    To evaluate {sup 11}C-choline PET/CT as a diagnostic tool for restaging prostate cancer (PCa), in a large, homogeneous and clinically relevant population of patients with biochemical recurrence (BCR) of PCa after primary therapy. The secondary aim was to assess the best timing for performing {sup 11}C-choline PET/CT during BCR. We retrospectively analysed 9,632 {sup 11}C-choline PET/CT scans performed in our institution for restaging PCa from January 2007 to June 2015. The inclusion criteria were: (1) proven PCa radically treated with radical prostatectomy (RP) or with primary external beam radiotherapy (EBRT); (2) PSA serum values available; (3) proven BCR (PSA >0.2 ng/mL after RP or PSA >2 ng/mL above the nadir after primary EBRT with rising PSA levels). Finally, 3,203 patients with recurrent PCa matching all the inclusion criteria were retrospectively enrolled and 4,426 scans were analysed. Overall, 52.8 % of the {sup 11}C-choline PET/CT scans (2,337/4,426) and 54.8 % of the patients (1,755/3,203) were positive. In 29.4 % of the scans, at least one distant finding was observed. The mean and median PSA values were, respectively, 4.9 and 2.1 ng/mL at the time of the scan (range 0.2 - 50 ng/mL). In our series, 995 scans were performed in patients with PSA levels between 1 and 2 ng/mL. In this subpopulation the positivity rate in the 995 scans was 44.7 %, with an incidence of distant findings of 19.2 % and an incidence of oligometastatic disease (one to three lesions) of 37.7 %. The absolute PSA value at the time of the scan and ongoing androgen deprivation therapy were associated with an increased probability of a positive {sup 11}C-choline PET/CT scan (p < 0.0001). In the ROC analysis, a PSA value of 1.16 ng/mL was the optimal cut-off value. In patients with a PSA value <1.16 ng/mL, 26.8 % of 1,426 {sup 11}C-choline PET/CT scans were positive, with oligometastatic disease in 84.7 % of positive scans. In a large cohort of patients, the feasibility of {sup 11}C

  20. Scientific journals in the SciELO database, indicators of impact and the relative position of Ambiente & Água

    Directory of Open Access Journals (Sweden)

    Nelson Wellausen Dias

    2010-12-01

    Full Text Available This editorial describes the process of periodic evaluation by CAPES, based on commercial indices proposed by companies such as the ISI FI by Thomson Reuters and SCImago by Scopus and public indices as proposed by SciELO and other freely calculated indices based on Google Scholar and investigates the impact position of the journal Ambiente & Agua compared with journals from the SciELO base. Results show that Ambiente & Agua is in the right path in the search for quality. Its editorial board strongly recommends that Brazilian public scientific agencies consider tools that are cost free and have large coverage for impact evaluation to allow the impact assessment of a range of emerging journals in a common and wide basis for all scientific journals.

  1. Scanning small angle X-ray scattering investigations of bone

    International Nuclear Information System (INIS)

    Rinnerthaler, S.

    1998-06-01

    An important characteristic of bone is its strength, which is determined by bone mass, architecture and material quality. From a physical point of view bone is a composite material consisting of an organic matrix (collagen) and of inlets of mineral crystals (hydroxyapatite). These components build up a hierarchical, heterogeneous structure. The size of the mineral crystals lies in the nano-meter range and can be investigated by positionsensitive Small-Angle X-ray Scattering (Scanning-SAXS) in a non-destructive way. The average thickness, the degree and direction of the predominant orientation, as well as some information about shape and arrangement of the mineral crystals were determined in bones of humans, mice, and baboons by Scanning-SAXS with respect to age, bone diseases (osteogenesis imperfecta, pycnodysostosis) or medical treatments (fluoride or alendronate) of osteoporosis. The crystal thickness and the degree of orientation is much smaller in young individuals than in adults and the predominant orientation of the mineral crystals is different in a mixture of bone and mineralized cartilage compared to bone. Further, because position-resolved measurements are now possible, results from Scanning-SAXS measurements could be compared with the results of other position resolved methods. Due to this new feature it was possible, for the first time, to correlate directly 'mottled' bone visible in back-scattered electron imaging with small η-parameters evaluated from SAXS-patterns and the course of the collagen fibers with the predominant orientation of the mineral crystals. Scanning-SAXS proved to be a powerful tool to characterize bone nano-structure. (author)

  2. Head CT scan

    Science.gov (United States)

    ... scan - orbits; CT scan - sinuses; Computed tomography - cranial; CAT scan - brain ... head size in children Changes in thinking or behavior Fainting Headache, when you have certain other signs ...

  3. Improving Completeness of Geometric Models from Terrestrial Laser Scanning Data

    Directory of Open Access Journals (Sweden)

    Clemens Nothegger

    2011-12-01

    Full Text Available The application of terrestrial laser scanning for the documentation of cultural heritage assets is becoming increasingly common. While the point cloud by itself is sufficient for satisfying many documentation needs, it is often desirable to use this data for applications other than documentation. For these purposes a triangulated model is usually required. The generation of topologically correct triangulated models from terrestrial laser scans, however, still requires much interactive editing. This is especially true when reconstructing models from medium range panoramic scanners and many scan positions. Because of residual errors in the instrument calibration and the limited spatial resolution due to the laser footprint, the point clouds from different scan positions never match perfectly. Under these circumstances many of the software packages commonly used for generating triangulated models produce models which have topological errors such as surface intersecting triangles, holes or triangles which violate the manifold property. We present an algorithm which significantly reduces the number of topological errors in the models from such data. The algorithm is a modification of the Poisson surface reconstruction algorithm. Poisson surfaces are resilient to noise in the data and the algorithm always produces a closed manifold surface. Our modified algorithm partitions the data into tiles and can thus be easily parallelized. Furthermore, it avoids introducing topological errors in occluded areas, albeit at the cost of producing models which are no longer guaranteed to be closed. The algorithm is applied to scan data of sculptures of the UNESCO World Heritage Site Schönbrunn Palace and data of a petrified oyster reef in Stetten, Austria. The results of the method’s application are discussed and compared with those of alternative methods.

  4. Heart PET scan

    Science.gov (United States)

    ... nuclear medicine scan; Heart positron emission tomography; Myocardial PET scan ... A PET scan requires a small amount of radioactive material (tracer). This tracer is given through a vein (IV), ...

  5. Fluorescence image excited by a scanning UV-LED light

    Science.gov (United States)

    Tsai, Hsin-Yi; Chen, Yi-Ju; Huang, Kuo-Cheng

    2013-03-01

    An optical scanning system using UV-LED light to induced fluorescence technology can enhance a fluorescence image significantly in a short period. It has several advantages such as lower power consumption, no scattering effect in skins, and multilayer images can be obtained to analyze skin disease. From the experiment results, the light intensity increases with increase spot size and decrease scanning speed, but the image resolution is oppositely. Moreover, the system could be widely used in clinical diagnosis and photodynamic therapy for skin disease because even the irradiated time of fluorescence substance is short but it will provide accurately positioning of fluorescence object.

  6. Influence of metabolic indicators, smoking, alcohol and socioeconomic position on mortality after breast cancer

    DEFF Research Database (Denmark)

    Larsen, Signe Benzon; Kroman, Niels; Ibfelt, Else Helene

    2015-01-01

    BACKGROUND: Factors differently distributed among social groups like obesity, metabolic syndrome, diabetes, smoking, and alcohol intake predict survival after breast cancer diagnosis and therefore might mediate part of the observed social inequality in survival. MATERIAL AND METHODS: We conducted...... a cohort study among 1250 postmenopausal breast cancer patients identified among 29 875 women in the Danish Diet, Cancer and Health Study. Participants completed questionnaires and anthropometric measurements were made at enrollment. Information on survival, socioeconomic position, and comorbidity...... circumference and diabetes, and smoking and alcohol affected but did not explain the social gradient. CONCLUSION: The findings indicate that these factors explain some but not all the social inequality in survival after breast cancer and that improvement of lifestyle to some extent would improve survival among...

  7. Aperture Determination in the LHC Based on an Emittance Blowup Technique with Collimator Position Scan

    CERN Document Server

    Assmann, R W; del Carmen Alabau, M; Giovannozzi, M; Muller, GJ; Redaelli, S; Schmidt, F; Tomas, R; Wenninger, J; Wollmann, D

    2011-01-01

    A new method to determine the LHC aperture was proposed. The new component is a collimator scan technique that refers the globally measured aperture limit to the shadow of the primary collimator, expressed in sigmas of rms beam size. As a by-product the BLM response to beam loss is quantified. The method is described and LHC measurement results are presented.

  8. Position and orientation tracking system

    International Nuclear Information System (INIS)

    Burks, B.L.; DePiero, F.W.; Armstrong, G.A.; Jansen, J.F.; Muller, R.C.; Gee, T.F.

    1998-01-01

    A position and orientation tracking system presents a laser scanning apparatus having two measurement pods, a control station, and a detector array. The measurement pods can be mounted in the dome of a radioactive waste storage silo. Each measurement pod includes dual orthogonal laser scanner subsystems. The first laser scanner subsystem is oriented to emit a first line laser in the pan direction. The second laser scanner is oriented to emit a second line laser in the tilt direction. Both emitted line lasers scan planes across the radioactive waste surface to encounter the detector array mounted on a target robotic vehicle. The angles of incidence of the planes with the detector array are recorded by the control station. Combining measurements describing each of the four planes provides data for a closed form solution of the algebraic transform describing the position and orientation of the target robotic vehicle. 14 figs

  9. Combined Modality Treatment for PET-Positive Non-Hodgkin Lymphoma: Favorable Outcomes of Combined Modality Treatment for Patients With Non-Hodgkin Lymphoma and Positive Interim or Postchemotherapy FDG-PET

    Energy Technology Data Exchange (ETDEWEB)

    Halasz, Lia M. [Harvard Radiation Oncology Program, Boston, Massachusetts (United States); Jacene, Heather A. [Department of Imaging, Dana-Farber Cancer Institute, and Department of Radiology, Brigham and Women' s Hospital, Boston, Massachusetts (United States); Catalano, Paul J. [Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Van den Abbeele, Annick D. [Department of Imaging, Dana-Farber Cancer Institute, and Department of Radiology, Brigham and Women' s Hospital, Boston, Massachusetts (United States); LaCasce, Ann [Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Mauch, Peter M. [Department of Radiation Oncology, Dana-Farber Cancer Institute, Brigham and Women' s Hospital, Boston, Massachusetts (United States); Ng, Andrea K., E-mail: ang@lroc.harvard.edu [Department of Radiation Oncology, Dana-Farber Cancer Institute, Brigham and Women' s Hospital, Boston, Massachusetts (United States)

    2012-08-01

    Purpose: To evaluate outcomes of patients treated for aggressive non-Hodgkin lymphoma (NHL) with combined modality therapy based on [{sup 18}F]fluoro-2-deoxy-2-D-glucose positron emission tomography (FDG-PET) response. Methods and Materials: We studied 59 patients with aggressive NHL, who received chemotherapy and radiation therapy (RT) from 2001 to 2008. Among them, 83% of patients had stage I/II disease. Patients with B-cell lymphoma received R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone)-based chemotherapy, and 1 patient with anaplastic lymphoma kinase-negative anaplastic T-cell lymphoma received CHOP therapy. Interim and postchemotherapy FDG-PET or FDG-PET/computed tomography (CT) scans were performed for restaging. All patients received consolidated involved-field RT. Median RT dose was 36 Gy (range, 28.8-50 Gy). Progression-free survival (PFS) and local control (LC) rates were calculated with and without a negative interim or postchemotherapy FDG-PET scan. Results: Median follow-up was 46.5 months. Thirty-nine patients had negative FDG-PET results by the end of chemotherapy, including 12 patients who had a negative interim FDG-PET scan and no postchemotherapy PET. Twenty patients were FDG-PET-positive, including 7 patients with positive interim FDG-PET and no postchemotherapy FDG-PET scans. The 3-year actuarial PFS rates for patients with negative versus positive FDG-PET scans were 97% and 90%, respectively. The 3-year actuarial LC rates for patients with negative versus positive FDG-PET scans were 100% and 90%, respectively. Conclusions: Patients who had a positive interim or postchemotherapy FDG-PET had a PFS rate of 90% at 3 years after combined modality treatment, suggesting that a large proportion of these patients can be cured with consolidated RT.

  10. Image quality of high-resolution CT with 16-channel multidetector-row CT. Comparison between helical scan and conventional step-shoot scan

    International Nuclear Information System (INIS)

    Sumikawa, Hiromitsu; Johkoh, Takeshi; Koyama, Mitsuhiro

    2005-01-01

    The aim of this study was to evaluate the image quality of high-resolution CT (HRCT) reconstructed from volumetric data with 16-channel multidetector-row CT (MDCT). Eleven autopsy lungs that were diagnosed histopathologically were scanned by 16-channel MDCT with the step-and-shoot scan mode and three helical scan modes. Each helical mode had each size of focal spot, pitch, and time of gantry rotation. HRCT images were reconstructed from the volumetric data with each helical mode and axial sequence data. Two observers evaluated the image quality and noted the most appropriate diagnosis for each imaging. Visualization of abnormal structures with one helical mode was equal to those with axial mode, whereas those with the other two helical modes were inferior to those with axial mode (Wilcoxon signed rank test; p<0.0001). There was no significant difference in diagnostic efficacy between modes. The image quality of HRCT with appropriate helical mode is equal to that with axial mode and diagnostic efficacy is equal among all modes. These results may indicate that sufficient HRCT images can be obtained by only one helical scan without the addition of conventional axial scans. (author)

  11. Evaluation of three lidar scanning strategies for turbulence measurements

    DEFF Research Database (Denmark)

    Newman, Jennifer F.; Klein, Petra M.; Wharton, Sonia

    2016-01-01

    Several errors occur when a traditional Doppler beam swinging (DBS) or velocity-azimuth display (VAD) strategy is used to measure turbulence with a lidar. To mitigate some of these errors, a scanning strategy was recently developed which employs six beam positions to independently estimate the u,...

  12. Position indicating split toroid for the RACE experiment

    International Nuclear Information System (INIS)

    Hurst, B.; Folkman, K.

    2007-01-01

    Aspects of the recent reactor accelerator coupled experiments (RACE) carried out at University of Texas Nuclear Engineering Teaching Laboratory will be discussed. In particular, a compact instrument that allowed a continuous non-invasive means of determining the relative electron beam position was developed. The operation of the instrument is similar to an inductive current pick up toroid except that the core is sectioned radially, which allows spatial information to be derived from the induced voltages. Results of initial tests, both in beam and with a pulser, will be presented along with plans to optimize future designs

  13. Design and performance of a beetle-type double-tip scanning tunneling microscope

    International Nuclear Information System (INIS)

    Jaschinsky, Philipp; Coenen, Peter; Pirug, Gerhard; Voigtlaender, Bert

    2006-01-01

    A combination of a double-tip scanning tunneling microscope with a scanning electron microscope in ultrahigh vacuum environment is presented. The compact beetle-type design made it possible to integrate two independently driven scanning tunneling microscopes in a small space. Moreover, an additional level for coarse movement allows the decoupling of the translation and approach of the tunneling tip. The position of the two tips can be controlled from the millimeter scale down to 50 nm with the help of an add-on electron microscope. The instrument is capable of atomic resolution imaging with each tip

  14. Comparative yield of positive brain Computed Tomography after implementing the NICE or SIGN head injury guidelines in two equivalent urban populations

    Energy Technology Data Exchange (ETDEWEB)

    Summerfield, R., E-mail: ruth.summerfield@uhns.nhs.u [Medical Imaging, University Hospital of North Staffordshire, City General Hospital, Stoke-on-Trent, Staffordshire ST4 6QG (United Kingdom); Macduff, R. [Glasgow Royal Infirmary, 84 Castle Street, Glasgow G4 0SF (United Kingdom); Davis, R. [Medical Imaging, University Hospital of North Staffordshire, City General Hospital, Stoke-on-Trent, Staffordshire ST4 6QG (United Kingdom); Sambrook, M. [Glasgow Royal Infirmary, 84 Castle Street, Glasgow G4 0SF (United Kingdom); Britton, I. [Medical Imaging, University Hospital of North Staffordshire, City General Hospital, Stoke-on-Trent, Staffordshire ST4 6QG (United Kingdom)

    2011-04-15

    Aims: To compare the yield of positive computed tomography (CT) brain examinations after the implementation of the National Institute for Clinical Excellence (NICE) or the Scottish Intercollegiate Guidance Network (SIGN) guidelines, in comparable urban populations in two teaching hospitals in England and Scotland. Materials and methods: Four hundred consecutive patients presenting at each location following a head injury who underwent a CT examination of the head according to the locally implemented guidelines were compared. Similar matched populations were compared for indication and yield. Yield was measured according to (1) positive CT findings of the sequelae of trauma and (2) intervention required with anaesthetic or intensive care unit (ICU) support, or neurosurgery. Results: The mean ages of patients at the English and Scottish centres were 49.9 and 49.2 years, respectively. Sex distribution was 64.1% male and 66.4% male respectively. Comparative yield was 23.8 and 26.5% for positive brain scans, 3 and 2.75% for anaesthetic support, and 3.75 and 2.5% for neurosurgical intervention. Glasgow Coma Score (GCS) <13 (NICE) and GCS {<=}12 and radiological or clinical evidence of skull fracture (SIGN) demonstrated the greatest statistical association with a positive CT examination. Conclusion: In a teaching hospital setting, there is no significant difference in the yield between the NICE and SIGN guidelines. Both meet the SIGN standard of >10% yield of positive scans. The choice of guideline to follow should be at the discretion of the local institution. The indications GCS <13 and clinical or radiological evidence of a skull fracture are highly predictive of intracranial pathology, and their presence should be an absolute indicator for fast-tracking the management of the patient.

  15. Scanning gamma camera

    International Nuclear Information System (INIS)

    Engdahl, L.W.; Batter, J.F. Jr.; Stout, K.J.

    1977-01-01

    A scanning system for a gamma camera providing for the overlapping of adjacent scan paths is described. A collimator mask having tapered edges provides for a graduated reduction in intensity of radiation received by a detector thereof, the reduction in intensity being graduated in a direction normal to the scanning path to provide a blending of images of adjacent scan paths. 31 claims, 15 figures

  16. Scanning usefulness for bone metastases diagnosis in the breast cancer follow-up

    International Nuclear Information System (INIS)

    Guillen, G.; Martinez, P.; Garcia, F.; Tres, A.

    1988-01-01

    It is studied the incidence of osseus metastases and the usefulness of 179 bone scanning realized in the diagnosis and follow-up (average: 23,6 months) of 87 patients operated by breast cancer. It is obvious the scan sensitivity and its unspecificity (15,08% phase-positives). In 13 (14,9%) patients who showed them, during the follow-up, scan was pathological at the moment of the osseus metastases diagnosis or a bit later; there were other clinical data or abnormal analytical ones of suspicion in 77% of them. The time average of appearance is 27 months after surgery. We concluded that the bone scan in the follow-up of breast cancer will be realized only when clinical or analytical suspicion of bone metastases. (Author)

  17. Pyrophosphate scan of the temporarily ischemized dog myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Duska, F.; Novak, J.; Vizda, J.; Kubicek, J.; Kafka, P.; Veverkova, O.

    1981-12-01

    In 9 dogs a transient myocardial ischemia was provoked using complete occlusion of the ramus interventricularis anterior of the left coronary artery. The occlusion was removed after 5, 10 or 15 min. Four hrs after removal of the occlusion a scan of the myocardium was carried out using sup(99m)Tc-labelled pyrophosphate. In 7 out of 9 dogs under study the scan was markedly positive, in 2 dogs negative. ECG demonstrated ischemic changes practically in all dogs; the changes became normal after removal of the occlusion, namely in 5 to 35 min. The histological examination of the tissue demonstrated in all 9 dogs only a slight impairment of the myocardium.

  18. Correlation between PSA, bone scan and Gleason score in patients with prostate cancer

    International Nuclear Information System (INIS)

    Mendoza, G.; Cano, R.; Morales, R.; Munoz, L.; Saavedra, P.; Aguilar, C.

    2004-01-01

    Full text: Prostate cancer is the third most common cancer among Peruvian males. Although radionuclide bone scans (BS) are frequently recommended as part of the staging evaluation for newly diagnosed prostate cancer, most scans are negative for metastases. It has been suggested that a routine bone scan is unnecessary in recently diagnosed prostate cancer if serum PSA is under 10 ng/mL. We hypothesized that Gleason score plus prostate-specific antigen (PSA), could predict for a positive bone scan (better that PSA alone), and that a low - risk group of patients could be identified in whom BS might be omitted. All patients who had both pathologic review of their prostate cancer biopsies and radionuclide BS at our institution from 1/93 to 12/95 were studied. Gleason score, PSA, and bone scan (Soloway Index) were determined in 165 patients. Bivariate analysis using chi (x2) was performed. The mean age of the 165 patients was 71.3 years, 109/165 (66.1%) had a 7-9 Gleason score and only 9/165 (5.5%) were well differentiated prostrate cancer. 82/165 (49.7%) had negative BS. When classifying patients according to their histological grade, the PSA median values were 11.8 ng/mL, 74.8 ng/mL and 116.4 ng/mL in well, median and poorly differentiated prostate cancer respectively. Using a cut off point of 10 ng/mL of PSA, the probability of having a positive BS in Gleason 7, 8 and 9 tumors were 0.109, 0.121 and 0.133 respectively. By using a cut off point of 20 ng/mL of PSA the possibility to have a positive BS in Gleason 7, 8 and 9 tumours were 0.182, 0.206 and 0.224 respectively. Gleason score plus PSA were independent predictors for a positive radionuclide BS in newly diagnosed prostate cancer patients. Considering that most of our patients have Gleason 7-9, the risk of bone metastases despite PSA levels between 10 - 20 ng/mL is not negligible. In our opinion, it is important to continue including bone scan in the staging assessment of prostate cancer. (author)

  19. Plague and the gallium scan: case report

    International Nuclear Information System (INIS)

    Stahly, T.L.; Shoop, J.D.

    1975-01-01

    Inflammation in the right axillary lymph nodes and the meninges was detected by 67 Ga-citrate scans in an 11-year-old boy with Yersinia pestis infection. This case provides another example of 67 Ga localizing to areas of infection, indicating potential utility in future cases of bubonic plague

  20. Automatic classification of DMSA scans using an artificial neural network

    Science.gov (United States)

    Wright, J. W.; Duguid, R.; Mckiddie, F.; Staff, R. T.

    2014-04-01

    DMSA imaging is carried out in nuclear medicine to assess the level of functional renal tissue in patients. This study investigated the use of an artificial neural network to perform diagnostic classification of these scans. Using the radiological report as the gold standard, the network was trained to classify DMSA scans as positive or negative for defects using a representative sample of 257 previously reported images. The trained network was then independently tested using a further 193 scans and achieved a binary classification accuracy of 95.9%. The performance of the network was compared with three qualified expert observers who were asked to grade each scan in the 193 image testing set on a six point defect scale, from ‘definitely normal’ to ‘definitely abnormal’. A receiver operating characteristic analysis comparison between a consensus operator, generated from the scores of the three expert observers, and the network revealed a statistically significant increase (α quality assurance assistant in clinical practice.

  1. Positive selection in octopus haemocyanin indicates functional links to temperature adaptation.

    Science.gov (United States)

    Oellermann, Michael; Strugnell, Jan M; Lieb, Bernhard; Mark, Felix C

    2015-07-05

    Octopods have successfully colonised the world's oceans from the tropics to the poles. Yet, successful persistence in these habitats has required adaptations of their advanced physiological apparatus to compensate impaired oxygen supply. Their oxygen transporter haemocyanin plays a major role in cold tolerance and accordingly has undergone functional modifications to sustain oxygen release at sub-zero temperatures. However, it remains unknown how molecular properties evolved to explain the observed functional adaptations. We thus aimed to assess whether natural selection affected molecular and structural properties of haemocyanin that explains temperature adaptation in octopods. Analysis of 239 partial sequences of the haemocyanin functional units (FU) f and g of 28 octopod species of polar, temperate, subtropical and tropical origin revealed natural selection was acting primarily on charge properties of surface residues. Polar octopods contained haemocyanins with higher net surface charge due to decreased glutamic acid content and higher numbers of basic amino acids. Within the analysed partial sequences, positive selection was present at site 2545, positioned between the active copper binding centre and the FU g surface. At this site, methionine was the dominant amino acid in polar octopods and leucine was dominant in tropical octopods. Sites directly involved in oxygen binding or quaternary interactions were highly conserved within the analysed sequence. This study has provided the first insight into molecular and structural mechanisms that have enabled octopods to sustain oxygen supply from polar to tropical conditions. Our findings imply modulation of oxygen binding via charge-charge interaction at the protein surface, which stabilize quaternary interactions among functional units to reduce detrimental effects of high pH on venous oxygen release. Of the observed partial haemocyanin sequence, residue 2545 formed a close link between the FU g surface and the

  2. SU-E-J-227: Breathing Pattern Consistency and Reproducibility: Comparative Analysis for Supine and Prone Body Positioning

    International Nuclear Information System (INIS)

    Laugeman, E; Weiss, E; Chen, S; Hugo, G; Rosu, M

    2014-01-01

    Purpose: Evaluate and compare the cycle-to-cycle consistency of breathing patterns and their reproducibility over the course of treatment, for supine and prone positioning. Methods: Respiratory traces from 25 patients were recorded for sequential supine/prone 4DCT scans acquired prior to treatment, and during the course of the treatment (weekly or bi-weekly). For each breathing cycle, the average(AVE), end-of-exhale(EoE) and end-of-inhale( EoI) locations were identified using in-house developed software. In addition, the mean values and variations for the above quantities were computed for each breathing trace. F-tests were used to compare the cycle-to-cycle consistency of all pairs of sequential supine and prone scans. Analysis of variances was also performed using population means for AVE, EoE and EoI to quantify differences between the reproducibility of prone and supine respiration traces over the treatment course. Results: Consistency: Cycle-to-cycle variations are less in prone than supine in the pre-treatment and during-treatment scans for AVE, EoE and EoI points, for the majority of patients (differences significant at p<0.05). The few cases where the respiratory pattern had more variability in prone appeared to be random events. Reproducibility: The reproducibility of breathing patterns (supine and prone) improved as treatment progressed, perhaps due to patients becoming more comfortable with the procedure. However, variability in supine position continued to remain significantly larger than in prone (p<0.05), as indicated by the variance analysis of population means for the pretreatment and subsequent during-treatment scans. Conclusions: Prone positioning stabilizes breathing patterns in most subjects investigated in this study. Importantly, a parallel analysis of the same group of patients revealed a tendency towards increasing motion amplitude of tumor targets in prone position regardless of their size or location; thus, the choice for body positioning

  3. Intrathoracic kidney. Diagnostic value of CT scan imaging

    International Nuclear Information System (INIS)

    Baillet, A.M.; Escure, M.N.

    1988-01-01

    Two cases are reported of an ectopic right kidney that was partially intrathoracic in position. Diagnosis was simple from CT scan imaging appearances, the examination being performed to investigate an intrathoracic mass. Images showed a tissular mass within a fatty zone in sections without contrast and the typical appearance of the kidney on sections with contrast [fr

  4. Trial making of a positive drawing phantom and its application to whole-body imaging devices

    International Nuclear Information System (INIS)

    Saegusa, Kenji; Arimizu, Noboru; Nakata, Tsuneo; Toyama, Haruo; Shiina, Isamu.

    1980-01-01

    In whole-body RI imaging, there are more instances of the positive pictures detecting the radioisotopes accumulating in morbid positions, such as Tc-99m bone scanning. The phantoms used to mutually compare RI imaging devices and to test their performance employ negative drawing targets embedded rather than positive ones. A simple positive drawing phantom has been made for trial, and applying this to whole-body scanning devices, the performance and the target drawing ability under different scanning conditions were comparatively examined. Though similar to Rollo's phantom, the phantom made for positive drawing uses acryl plate for its outer structure and target portions. The positive targets are cylindrical, and the diameters are 2, 4, 6, 8, 10, and 20 mm, and the subject contrasts are 5, 2, 1, 0.5 and 0.2. The aqueous solution of Tc-99m of about 2 mCi was injected into the phantom, and this was scanned with a whole-body camera and a multi-detector type whole-body scanner. With the phantom pictures close to actual clinical condition, the positive drawing phantom is conveniently capable of comparing the respective imaging devices for intended purposes. (J.P.N.)

  5. Cardiac events in patients with positive exercise ECG and normal myocardial perfusion scan - a retrospective study

    International Nuclear Information System (INIS)

    Marshman, K.; Thomson, L.E.J.; Rowe, C.C.; Burns, A.J.; Woon, F.S.

    2002-01-01

    Full text: The low risk of future cardiac events following a normal myocardial perfusion study with normal stress ECG has been well documented. However, there is little literature regarding the prognosis in patients with a positive stress ECG (PosETT) and normal myocardial perfusion scan (MPS). A search of our database over an eighteen month period identified 21 patients who fitted study criteria. A PosETT was defined as stress induced horizontal or downsloping ST depression > 1mm in one or more leads with a normal baseline 12 lead ECG. Patients were divided into two subgroups depending on the severity of ST depression. A mildly PosETT was defined as ST depression of 1-1.5mm (n=10) and strongly PosETT was defined as ST depression of >2mm in at least one lead with depression in other leads (n=l 1). A normal MPS was defined as absence of reversible perfusion defects on SPECT imaging. Technetium 99m Tetrofosmin was the imaging agent used in 18/21 patients. All 21 patients exercised using the Bruce protocol for 3-12 minutes, and 9 experienced chest pain 12 months after the MPS, referring physicians were contacted. Cardiac events were defined as cardiac death, myocardial infarction, unstable angina, cardiac failure, revascularisation or a coronary angiogram demonstrating >70% stenosis. To date, follow up is complete in 11 patients with one confirmed case of single vessel revascularisation 3 months post MPS. Full follow up data will be presented. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

  6. Relationship of condylar position to disc position and morphology

    Energy Technology Data Exchange (ETDEWEB)

    Incesu, L.; Taskaya-Yilmaz, N. E-mail: nergizy@omu.edu.tr; Oeguetcen-Toller, M.; Uzun, E

    2004-09-01

    Introduction/objective: The purpose of this study was to assess whether condylar position, as depicted by magnetic resonance imaging, was an indicator of disc morphology and position. Methods and material: One hundred and twenty two TMJs of 61 patients with temporomandibular joint disorder were examined. Condylar position, disc deformity and degree of anterior disc displacement were evaluated by using magnetic resonance imaging. Results and discussion: Posterior condyle position was found to be the main feature of temporomandibular joints with slight and moderate anterior disc displacement. No statistical significance was found between the condylar position, and reducing and nonreducing disc positions. On the other hand, superior disc position was found to be statistically significant for centric condylar position. Conclusion: It was concluded that posterior condyle position could indicate anterior disc displacement whereas there was no relation between the position of condyle and the disc deformity.

  7. A case of pineal teratoma with intraventricular free fat on CT scan

    International Nuclear Information System (INIS)

    Uede, Teiji; Takaya, Satoru; Shinya, Toshiyuki; Tanabe, Sumiyoshi; Hashi, Kazuo; Sohma, Tsutomu.

    1986-01-01

    Detection of an intraventricular or intratumoral fat-fluid level on the plain craniograms has been known as a characteristic sign indicating the presence of intracranial teratomatous tumors. On CT scans, however, only thirteen cases have been previously reported to be found an intraventricular and/or subarachnoid free fat associated with spontaneous ruptures of these tumors. We reported a case of pineal teratoma with intraventricular free-fat seen on CT scans. A nine-year-old male with precocious puberty was admitted to our hospital complaining a moderate nonpulsatile headache. Neurological examinations were normal without signs of meningeal irritation. The serum and CSF titer of HCG were raised markedly. The laboratory data of the CSF were normal and there were no pathological cells in the CSF. The CT scans revealed a large heterogeneous mass containing multiple areas of negative density in the pineal region. There were negative density droplets in the bilateral frontal horn on the same CT scans indicating a presence of free fats. At surgery, an yellowish oily material was drained from the tumor, but there was no sign of meningitis over the cortical surface of the occipital lobe. An intraventricular free fat on CT scan have been reported in fourteen cases including ours following the first case described by Fawcitt in 1976. Although most of the cases presented headache, only two cases was diagnosed clinically as chemical meningitis. Pathological changes indicating granulomatous meningitis, however, were noted in five cases, all of them presenting seizure attacks. (author)

  8. Navicular bone position determined by positional MRI: a reproducibility study

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Philip; Nybing, Janus D. [Copenhagen University Hospital Frederiksberg and Bispebjerg, Department of Radiology, Frederiksberg (Denmark); Johannsen, Finn E.; Stallknecht, Sandra E. [Copenhagen University Hospital Bispebjerg, Institute of Sports Medicine Copenhagen, Copenhagen, NV (Denmark); Hangaard, Stine; Hansen, Bjarke B. [Copenhagen University Hospital Frederiksberg, Parker Institute, Department of Rheumatology, Frederiksberg (Denmark); Boesen, Mikael [Copenhagen University Hospital Frederiksberg and Bispebjerg, Department of Radiology, Frederiksberg (Denmark); Copenhagen University Hospital Frederiksberg, Parker Institute, Department of Rheumatology, Frederiksberg (Denmark)

    2016-02-15

    To examine intraobserver, interobserver and between-day reproducibility of positional MRI for evaluation of navicular bone height (NVH) and medial navicular position (MNP). Positional MRI (pMRI) of the foot was performed on ten healthy participants (0.25 T G-scanner). Scanning was performed in supine and standing position, respectively. Two radiologists evaluated the images in a blinded manner. Reliability and agreement were assessed by calculation of intraclass correlation coefficient (ICC) and 95 % limits of agreement as a percentage of the mean (LOA%). Intraobserver and interobserver reliability was ''substantial'' in both supine and standing position (ICC 0.86-0.98) and showed good agreement (LOA% 4.9-14.7 %). Between-day reliability of navicular height and medial navicular position in standing position remained substantial (ICC 0.85-0.92) with adequate agreement (LOA% 8.3-19.8 %). In supine position between-day reliability was ''moderate'' for NVH (ICC 0.72) and ''slight'' for MNP (ICC 0.39). Agreement remained adequate between-days for MNP in supine position (LOA% 17.7 %), but it was less than adequate for NVH in supine position (LOA% 24.2 %). Navicular height and medial navicular position can be measured by pMRI in a very reproducible manner within and between observers. Increased measurement variation is observed between-days in supine position, which may be due to small positional differences or other unknown biomechanical factors. (orig.)

  9. Navicular bone position determined by positional MRI: a reproducibility study

    International Nuclear Information System (INIS)

    Hansen, Philip; Nybing, Janus D.; Johannsen, Finn E.; Stallknecht, Sandra E.; Hangaard, Stine; Hansen, Bjarke B.; Boesen, Mikael

    2016-01-01

    To examine intraobserver, interobserver and between-day reproducibility of positional MRI for evaluation of navicular bone height (NVH) and medial navicular position (MNP). Positional MRI (pMRI) of the foot was performed on ten healthy participants (0.25 T G-scanner). Scanning was performed in supine and standing position, respectively. Two radiologists evaluated the images in a blinded manner. Reliability and agreement were assessed by calculation of intraclass correlation coefficient (ICC) and 95 % limits of agreement as a percentage of the mean (LOA%). Intraobserver and interobserver reliability was ''substantial'' in both supine and standing position (ICC 0.86-0.98) and showed good agreement (LOA% 4.9-14.7 %). Between-day reliability of navicular height and medial navicular position in standing position remained substantial (ICC 0.85-0.92) with adequate agreement (LOA% 8.3-19.8 %). In supine position between-day reliability was ''moderate'' for NVH (ICC 0.72) and ''slight'' for MNP (ICC 0.39). Agreement remained adequate between-days for MNP in supine position (LOA% 17.7 %), but it was less than adequate for NVH in supine position (LOA% 24.2 %). Navicular height and medial navicular position can be measured by pMRI in a very reproducible manner within and between observers. Increased measurement variation is observed between-days in supine position, which may be due to small positional differences or other unknown biomechanical factors. (orig.)

  10. Scanning tunneling microscopy II further applications and related scanning techniques

    CERN Document Server

    Güntherodt, Hans-Joachim

    1992-01-01

    Scanning Tunneling Microscopy II, like its predecessor, presents detailed and comprehensive accounts of the basic principles and broad range of applications of STM and related scanning probe techniques. The applications discussed in this volume come predominantly from the fields of electrochemistry and biology. In contrast to those described in Vol. I, these sudies may be performed in air and in liquids. The extensions of the basic technique to map other interactions are described inchapters on scanning force microscopy, magnetic force microscopy, scanning near-field optical microscopy, together with a survey of other related techniques. Also described here is the use of a scanning proximal probe for surface modification. Togehter, the two volumes give a comprehensive account of experimental aspcets of STM. They provide essentialreading and reference material for all students and researchers involvedin this field.

  11. PWMScan: a fast tool for scanning entire genomes with a position-specific weight matrix.

    Science.gov (United States)

    Ambrosini, Giovanna; Groux, Romain; Bucher, Philipp

    2018-03-05

    Transcription factors (TFs) regulate gene expression by binding to specific short DNA sequences of 5 to 20-bp to regulate the rate of transcription of genetic information from DNA to messenger RNA. We present PWMScan, a fast web-based tool to scan server-resident genomes for matches to a user-supplied PWM or TF binding site model from a public database. The web server and source code are available at http://ccg.vital-it.ch/pwmscan and https://sourceforge.net/projects/pwmscan, respectively. giovanna.ambrosini@epfl.ch. SUPPLEMENTARY DATA ARE AVAILABLE AT BIOINFORMATICS ONLINE.

  12. CT Scan

    Science.gov (United States)

    ... disease, lung nodules and liver masses Monitor the effectiveness of certain treatments, such as cancer treatment Detect ... scan done in a hospital or an outpatient facility. CT scans are painless and, with newer machines, ...

  13. Renal scan

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003790.htm Renal scan To use the sharing features on this ... anaphylaxis . Alternative Names Renogram; Kidney scan Images Kidney anatomy Kidney - blood and urine flow References Chernecky CC, ...

  14. Precursor and Neutral Loss Scans in an RF Scanning Linear Quadrupole Ion Trap

    Science.gov (United States)

    Snyder, Dalton T.; Szalwinski, Lucas J.; Schrader, Robert L.; Pirro, Valentina; Hilger, Ryan; Cooks, R. Graham

    2018-03-01

    Methodology for performing precursor and neutral loss scans in an RF scanning linear quadrupole ion trap is described and compared to the unconventional ac frequency scan technique. In the RF scanning variant, precursor ions are mass selectively excited by a fixed frequency resonance excitation signal at low Mathieu q while the RF amplitude is ramped linearly to pass ions through the point of excitation such that the excited ion's m/z varies linearly with time. Ironically, a nonlinear ac frequency scan is still required for ejection of the product ions since their frequencies vary nonlinearly with the linearly varying RF amplitude. In the case of the precursor scan, the ejection frequency must be scanned so that it is fixed on a product ion m/z throughout the RF scan, whereas in the neutral loss scan, it must be scanned to maintain a constant mass offset from the excited precursor ions. Both simultaneous and sequential permutation scans are possible; only the former are demonstrated here. The scans described are performed on a variety of samples using different ionization sources: protonated amphetamine ions generated by nanoelectrospray ionization (nESI), explosives ionized by low-temperature plasma (LTP), and chemical warfare agent simulants sampled from a surface and analyzed with swab touch spray (TS). We lastly conclude that the ac frequency scan variant of these MS/MS scans is preferred due to electronic simplicity. In an accompanying manuscript, we thus describe the implementation of orthogonal double resonance precursor and neutral loss scans on the Mini 12 using constant RF voltage. [Figure not available: see fulltext.

  15. A scanning point source for quality control of FOV uniformity in GC-PET imaging

    International Nuclear Information System (INIS)

    Bergmann, H.; Minear, G.; Dobrozemsky, G.; Nowotny, R.; Koenig, B.

    2002-01-01

    Aim: PET imaging with coincidence cameras (GC-PET) requires additional quality control procedures to check the function of coincidence circuitry and detector zoning. In particular, the uniformity response over the field of view needs special attention since it is known that coincidence counting mode may suffer from non-uniformity effects not present in single photon mode. Materials and methods: An inexpensive linear scanner with a stepper motor and a digital interface to a PC with software allowing versatile scanning modes was developed. The scanner is used with a source holder containing a Sodium-22 point source. While moving the source along the axis of rotation of the GC-PET system, a tomographic acquisition takes place. The scan covers the full axial field of view of the 2-D or 3-D scatter frame. Depending on the acquisition software, point source scanning takes place continuously while only one projection is acquired or is done in step-and-shoot mode with the number of positions equal to the number of gantry steps. Special software was developed to analyse the resulting list mode acquisition files and to produce an image of the recorded coincidence events of each head. Results: Uniformity images of coincidence events were obtained after further correction for systematic sensitivity variations caused by acquisition geometry. The resulting images are analysed visually and by calculating NEMA uniformity indices as for a planar flood field. The method has been applied successfully to two different brands of GC-PET capable gamma cameras. Conclusion: Uniformity of GC-PET can be tested quickly and accurately with a routine QC procedure, using a Sodium-22 scanning point source and an inexpensive mechanical scanning device. The method can be used for both 2-D and 3-D acquisition modes and fills an important gap in the quality control system for GC-PET

  16. The value of SPECT bone scans in diagnosis of patients with zygapophseal joint pain

    International Nuclear Information System (INIS)

    Hu Jiajia; Liang Yu; Li Biao; Zhu Chengmo; Chen Gang; Wang Chao; Tian Weijia; Qu Liumin

    2008-01-01

    Objective: Bone scintigraphy with SPECT of the lumbar spine allows identification of lesions not seen with planar imaging, in patients with chronic low back pain. The aim of this study was to investigate the value of SPECT bone scans in diagnosis of patients with zygapophyseal joint pain. Methods: Thirty-five consecutive patients in Ruijin hospital from July 2006 to March 2007 with low back pain were en- rolled. All patients underwent bone scintigraphy with SPECT. According to the results of SPECT, patients with isotope-uptake joints received injections at the levels where abnormalities were identified on the scan. Patients with negative scans received other treatment (conservative treatment or surgery) but not facet joint injection. Clinical records were collected at 1-, 3-, and 6-month in SPECT-positive group after their initial treatment. And the SPECT-negative group were followed up at 6-month after therapy. Statistical analysis was performed with SPSS 10.0. Patients with SPECT-positive and -negative results were performed with the grouped t-test. Visual analog scales (VAS) were with the paired t-test used in patients with positive scans at before and after treatment. Results: Fifteen cases had facetal uptake of isotope on SPECT bone scans. After facet joint injection, 85.7% patients (12/14, 1 patient was excluded for operation) had improvement in pain score at 1-month, 78.6% (11/14) at 3-month, and 50.0% (7/14) at 6-month. Of 20 negative cases, 3 were treated by surgery and 17 by conservative treatment. All 20 cases were followed up for 6 months and 70.0% (14/20) had long time pain relief. Conclusion: SPECT bone scans are helpful to identify patients with low back pain who would benefit from facet joint injections. (authors)

  17. 99mTc-MDP Three Phase Bone Scan - An Important Imaging Modality in the Diagnosis of Bone Infection in Children

    International Nuclear Information System (INIS)

    Sethi, R.S.; Mittal, B.R.; Bhattacharya, A.; Singh, B.; Jindal, S.K.

    2002-01-01

    In patients suspected to have osteomyelitis, three-phase bone scan is one of the earlier investigations to become positive. Early diagnosis helps in starting the appropriate therapy and thus reducing morbidity. A retrospective analysis of scintigraphic findings of 53 children (37 boys, 16 girls) with mean age of 7.4 years (25 days - 2 years), referred for three-phase bone scan to rule out osteomyelitis was done. The presenting signs and symptoms in all children in order of frequency were swelling of body part, guarding, fever of unknown origin. Limitation of movement of body part was the most frequent sign in infants below 6 months of age. In 32 (60.3%) of these 53 children, x-rays were normal. Eleven (20.7%) of the 53 children had normal three phase bone scan. Nine children (16.9%) had increased blood flow along with increased soft tissue tracer concentration in the involved area suggesting soft tissue inflammation / infection. Five (9.4%) children who presented with multiple abscesses over extremities with the suspicion of immunodeficiency also had positive three-phase bone scan. All these 5 children had pus culture positive for staphylococcus aureus. Four (7.5%) children had thalassemia major and were on regular blood transfusion. Three of these 4 children showed positive three-phase bone scan while in the fourth patient bone phase (3rd phase) was normal suggesting soft tissue inflammation only. One child who was a case of Non-Hodgkin's lymphoma and had recently finished chemotherapy also showed positive three-phase bone scan. One infant who had positive three-phase bone scan with nonspecific abnormality on chest x-ray was diagnosed to have Caffey's disease, while his other twin showed a normal bone scan. In twenty-four children (45.2%) three-phase bone scan was positive involving mostly one extremity. According to the frequency of site of involvement these were knee, elbow and ankle. Most frequent bones involved were femur followed by humerus. Staphylococcus

  18. Precision controlled atomic resolution scanning transmission electron microscopy using spiral scan pathways

    Science.gov (United States)

    Sang, Xiahan; Lupini, Andrew R.; Ding, Jilai; Kalinin, Sergei V.; Jesse, Stephen; Unocic, Raymond R.

    2017-03-01

    Atomic-resolution imaging in an aberration-corrected scanning transmission electron microscope (STEM) can enable direct correlation between atomic structure and materials functionality. The fast and precise control of the STEM probe is, however, challenging because the true beam location deviates from the assigned location depending on the properties of the deflectors. To reduce these deviations, i.e. image distortions, we use spiral scanning paths, allowing precise control of a sub-Å sized electron probe within an aberration-corrected STEM. Although spiral scanning avoids the sudden changes in the beam location (fly-back distortion) present in conventional raster scans, it is not distortion-free. “Archimedean” spirals, with a constant angular frequency within each scan, are used to determine the characteristic response at different frequencies. We then show that such characteristic functions can be used to correct image distortions present in more complicated constant linear velocity spirals, where the frequency varies within each scan. Through the combined application of constant linear velocity scanning and beam path corrections, spiral scan images are shown to exhibit less scan distortion than conventional raster scan images. The methodology presented here will be useful for in situ STEM imaging at higher temporal resolution and for imaging beam sensitive materials.

  19. Modeling of MOEMS electromagnetic scanning grating mirror for NIR micro-spectrometer

    Directory of Open Access Journals (Sweden)

    Ying Zhou

    2016-02-01

    Full Text Available In this paper, the mathematical model is developed for researching the detailed electromagnetic mechanism of MOEMS scanning mirror. We present the relationship between spectral range and optical scanning angle. Furthermore, the variation tendencies of resonant frequency and maximal torsional angle are studied in detail under different aspect ratios of MOEMS scanning mirror and varied dimensions of torsional bar. The numerical results and Finite Element Analysis simulations both indicate that the thickness of torsional bar is the most important factor. The maximal torsional angle appears when the aspect ratio equals to 1. This mathematical model is an effective way for designing the MOEMS electromagnetic scanning grating mirror in actual fabrication.

  20. Comparison of radionuclide scans with computer-assisted tomography in diagnosis of intracranial disease

    International Nuclear Information System (INIS)

    Clifford, J.R.; Connolly, E.S.; Voorhies, R.M.

    1976-01-01

    Radionuclide brain scans were compared with computer-assisted tomography (CAT) for the diagnosis of intracranial disorders in 297 patients. The diagnosis was confirmed in 281 patients who formed the population for the study. The radionuclide scan was false positive for 12 patients (3.9 percent) and false negative for eight (2.6 percent). The CAT was false positive for three patients (1 percent) and false negative for one (0.3 percent). In the 133 patients in whom both tests were negative, no evidence of central nervous system pathology has been found during the 6 to 18 month follow-up. Brain tumors and intracerebral hemorrhage are more readily detectable with CAT

  1. Commissioning and cross-comparison of four scanning water tanks

    Directory of Open Access Journals (Sweden)

    Daniel Saenz

    2016-03-01

    Full Text Available Purpose: Water scanning systems are commonly used for data collection to characterize dosimetric properties of photon and electron beams, and the commissioning of such systems has been previously described. The aim in this study, however, was to investigate tank-specific dependencies as well as conduct a dosimetric comparison between four distinct water scanning systems.Methods: Four water scanning systems were studied including the PTW MP3-M Phantom Tank, the Standard Imaging DoseView 3D, the IBA Blue Phantom, and the Sun Nuclear 3D Scanner. Mechanical accuracy and reproducibility was investigated by driving the chamber holder to nominal positions relative to a zero point and using a leveled caliper with 30 cm range to measure the actual position. Dosimetric measurements were also performed not only to compare percent-depth-dose (PDD curves and profiles between tanks but also to assess dependencies such as directionality, scanning speed, and reproducibility for each tank individually. A PTW Semiflex 31010 ionization chamber with a sensitive volume of 0.125 cc was used at a Varian Clinac 2300 linear accelerator.Results: Mechanical precision was ensured to within 0.1 mm with the standard deviation (SD of reproducibility <0.1 mm for measurements made with calipers. Dependencies on scanning direction and speed are presented. 6 MV PDDs between tanks agreed to within 0.6% relative to an averaged PDD beyond dmax and within 2.5% in the build-up region. Specifically, the maximum difference was 1.0% between MP3-M and Blue Phantom at 6.1 cm depth. Lateral profiles agreed between tanks within 0.5% in the central 80% of the field. 6 MeV PDD maximum difference was 1.3% occurring at the steepest portion, where the R50 was nevertheless within 0.6 mm across tanks. Setup uncertainties estimated at ≤1 mm are presumed to have contributed some of the difference between water tank data.Conclusion: Modern water scanning systems have achieved high accuracy across

  2. Fuzzy-neural network in the automatic detection and volumetry of the spleen on spiral CT scans

    International Nuclear Information System (INIS)

    Heitmann, K.R.; Mainz Univ.; Rueckert, S.; Heussel, C.P.; Thelen, M.; Kauczor, H.U.; Uthmann, T.

    2000-01-01

    Purpose: To assess spleen segmentation and volumetry in spiral CT scans with and without pathological changes of splenic tissue. Methods: The image analysis software HYBRIKON is based on region growing, self-organized neural nets, and fuzzy-anatomic rules. The neural nets were trained with spiral CT data from 10 patients, not used in the following evaluation on spiral CT scans from 19 patients. An experienced radiologist verified the results. The true positive and false positive areas were compared in terms to the areas marked by the radiologist. The results were compared with a standard thresholding method. Results: The neural nets achieved a higher accuracy than the thresholding method. Correlation coefficient of the fuzzy-neural nets: 0.99 (thresholding: 0.63). Mean true positive rate: 90% (thresholding: 75%), mean false positive rate: 5% (thresholding>100%). Pitfalls were caused by accessory spleens, extreme changes in the morphology (tumors, metastases, cysts), and parasplenic masses. Conclusions: Self-organizing neural nets combined with fuzzy rules are ready for use in the automatic detection and volumetry of the spleen in spiral CT scans. (orig.) [de

  3. Nanomanipulation and nanofabrication with multi-probe scanning tunneling microscope: from individual atoms to nanowires.

    Science.gov (United States)

    Qin, Shengyong; Kim, Tae-Hwan; Wang, Zhouhang; Li, An-Ping

    2012-06-01

    The wide variety of nanoscale structures and devices demands novel tools for handling, assembly, and fabrication at nanoscopic positioning precision. The manipulation tools should allow for in situ characterization and testing of fundamental building blocks, such as nanotubes and nanowires, as they are built into functional devices. In this paper, a bottom-up technique for nanomanipulation and nanofabrication is reported by using a 4-probe scanning tunneling microscope (STM) combined with a scanning electron microscope (SEM). The applications of this technique are demonstrated in a variety of nanosystems, from manipulating individual atoms to bending, cutting, breaking carbon nanofibers, and constructing nanodevices for electrical characterizations. The combination of the wide field of view of SEM, the atomic position resolution of STM, and the flexibility of multiple scanning probes is expected to be a valuable tool for rapid prototyping in the nanoscience and nanotechnology.

  4. Seleno methionine-75 as a scanning agent for neuroblastoma

    International Nuclear Information System (INIS)

    Covington, E.E.; D'Angio, G.J.; Helson, L.; Romano, R.W.

    1974-01-01

    Neuroblastoma is a functioning tumor and patients with this tumor are known to excrete vanilmandelic acid and other degradation products of norepinephrine. It also accumulates and produces excess cystathionine for which methionine is a precursor in the normal anabolic pathway. This was the rationale for testing 75 Se-methionine as a possible scanning agent in patients with neuroblastoma. D'Angio et al reported the results of a preliminary investigation in which 3 of 4 patients with neuroblastoma, all with known metastases of the skull, had positive scans correctly localizing the disease. These preliminary data seemed encouraging, and further investigation was undertaken. The results are reported

  5. Wear Analysis of Die Inserts in the Hot Forging Process of a Forked Type Forging Using Reverse Scanning Techniques

    Directory of Open Access Journals (Sweden)

    Łukasz Dworzak

    2017-12-01

    Full Text Available This article presents a wear analysis of die inserts used in the hot forging process of a forked forging (yoke, an element applied in steering systems of passenger vehicles. Studies involved the application of an original reverse scanning method intended for rapid and reliable wear analysis of forging tools (with complicated shape affording easy assessment without the need to dismount tools from the forging unit. The developed method involves analysis of progressive wear of forging tools based on measurements (scanning of forgings periodically collected from the process and constitutes a useful tool for measurement and testing. As the authors’ earlier works have demonstrated, the proposed new approach to analysis of tool wear with the application of reverse 3D scanning has proven successful in multiple instances in the case of axially symmetrical objects. The presented results of studies indicate that it is possible to utilize the expanded method to analyze the lifetime of forging tools, including tools with complex geometry. Application of the reverse scanning method allows for continuous and practical monitoring of the condition of forging tools over the course of the forging process and should have a positive impact on improving production output and reducing production costs.

  6. Immune complexes, gallium lung scans, and bronchoalveolar lavage in idiopathic interstitial pneumonitis-fibrosis

    International Nuclear Information System (INIS)

    Gelb, A.F.; Dreisen, R.B.; Epstein, J.D.; Silverthorne, J.D.; Bickel, Y.; Fields, M.; Border, W.A.; Taylor, C.R.

    1983-01-01

    We obtained results of lung immune complexes (LIC), circulating immune complexes (CIC), 48-hour gallium lung scans (scans), bronchoalveolar lavage (BAL), and pulmonary function tests in 20 patients with idiopathic interstitial pneumonitis-fibrosis. Sixteen patients had predominantly interstitial (13 cases UIP) and/or intraalveolar (3 cases DIP) cellular disease (group 1). Prior to corticosteroid therapy in group 1, scans were positive in 75 percent, CIC were elevated in 86 percent, LIC were present in 64 percent, and BAL was abnormal in 90 percent. Duration of follow-up after treatment was 3.5 +/- 1.0 year. In group 1 after treatment with corticosteroids in 13 patients and corticosteroids and penicillamine (three patients) and plasmapheresis (one patient), only four patients remain stable or improved. After corticosteroid therapy, elevated CIC returned to normal values despite progressive patient deterioration. In three patients, lung immune complexes were still detected after circulating immune complexes had returned to normal after corticosteroid therapy. In group 2 were four patients with fibrotic disease; scans and CIC were uniformly negative, LIC were weakly present in only one patient, and BAL was abnormal in all. Despite corticosteroid therapy, all have died or deteriorated. These results suggest that positive gallium lung scans, BAL, circulating immune complexes, and to a lesser extent, lung immune complexes are associated with the cellular phase of interstitial pneumonia, but do not reliably identify a corticosteroid-responsive group

  7. High-speed, random-access fluorescence microscopy: I. High-resolution optical recording with voltage-sensitive dyes and ion indicators.

    Science.gov (United States)

    Bullen, A; Patel, S S; Saggau, P

    1997-07-01

    The design and implementation of a high-speed, random-access, laser-scanning fluorescence microscope configured to record fast physiological signals from small neuronal structures with high spatiotemporal resolution is presented. The laser-scanning capability of this nonimaging microscope is provided by two orthogonal acousto-optic deflectors under computer control. Each scanning point can be randomly accessed and has a positioning time of 3-5 microseconds. Sampling time is also computer-controlled and can be varied to maximize the signal-to-noise ratio. Acquisition rates up to 200k samples/s at 16-bit digitizing resolution are possible. The spatial resolution of this instrument is determined by the minimal spot size at the level of the preparation (i.e., 2-7 microns). Scanning points are selected interactively from a reference image collected with differential interference contrast optics and a video camera. Frame rates up to 5 kHz are easily attainable. Intrinsic variations in laser light intensity and scanning spot brightness are overcome by an on-line signal-processing scheme. Representative records obtained with this instrument by using voltage-sensitive dyes and calcium indicators demonstrate the ability to make fast, high-fidelity measurements of membrane potential and intracellular calcium at high spatial resolution (2 microns) without any temporal averaging.

  8. Using a laser scanning camera for reactor inspection

    International Nuclear Information System (INIS)

    Armour, I.A.; Adrain, R.S.; Klewe, R.C.

    1984-01-01

    Inspection of nuclear reactors is normally carried out using TV or film cameras. There are, however, several areas where these cameras show considerable shortcomings. To overcome these difficulties, laser scanning cameras have been developed. This type of camera can be used for general visual inspection as well as the provision of high resolution video images with high ratio on and off-axis zoom capability. In this paper, we outline the construction and operation of a laser scanning camera and give examples of how it has been used in various power stations, and indicate future potential developments. (author)

  9. Next-generation sequencing indicates false-positive MRD results and better predicts prognosis after SCT in patients with childhood ALL.

    Science.gov (United States)

    Kotrova, M; van der Velden, V H J; van Dongen, J J M; Formankova, R; Sedlacek, P; Brüggemann, M; Zuna, J; Stary, J; Trka, J; Fronkova, E

    2017-07-01

    Minimal residual disease (MRD) monitoring via quantitative PCR (qPCR) detection of Ag receptor gene rearrangements has been the most sensitive method for predicting prognosis and making post-transplant treatment decisions for patients with ALL. Despite the broad clinical usefulness and standardization of this method, we and others have repeatedly reported the possibility of false-positive MRD results caused by massive B-lymphocyte regeneration after stem cell transplantation (SCT). Next-generation sequencing (NGS) enables precise and sensitive detection of multiple Ag receptor rearrangements, thus providing a more specific readout compared to qPCR. We investigated two cohorts of children with ALL who underwent SCT (30 patients and 228 samples). The first cohort consisted of 17 patients who remained in long-term CR after SCT despite having low MRD positivity (SCT monitoring using qPCR. Only one of 27 qPCR-positive samples was confirmed to be positive by NGS. Conversely, 10 of 15 samples with low qPCR-detected MRD positivity from 13 patients who subsequently relapsed were also confirmed to be positive by NGS (P=0.002). These data show that NGS has a better specificity in post-SCT ALL management and indicate that treatment interventions aimed at reverting impending relapse should not be based on qPCR only.

  10. Indication, organization, practical implementation and interpretation guidelines for retrospective CGM recording: A French position statement.

    Science.gov (United States)

    Joubert, M; Baillot-Rudoni, S; Catargi, B; Charpentier, G; Esvant, A; Franc, S; Guerci, B; Guilhem, I; Melki, V; Merlen, E; Penfornis, A; Renard, E; Riveline, J P; Schaepelynck, P; Sola-Gazagnes, A; Hanaire, H

    2015-12-01

    The benefits of retrospective continuous glucose monitoring (retroCGM) recording have been widely explored in clinical studies, and many diabetes physicians routinely use this examination. However, the method of interpretation of CGM recordings has never been precisely described. An expert French panel of physicians met for two days to discuss several aspects of retroCGM use and to produce a position statement. The guidelines cover the indications for retroCGM, the general organization and practical implementation of CGM recordings, a description of the different devices available and guidelines for the interpretation of retroCGM recordings. This consensus document should help clinicians in the proper use of retroCGM. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  11. Gallium-67 scanning in patients with malignant pleural mesothelioma

    International Nuclear Information System (INIS)

    Nakano, Takashi; Maeda, Juichiro; Iwahashi, Noriaki; Tamura, Shinsuke; Hada, Toshikazu; Higashino, Kazuya

    1990-01-01

    The findings of gallium-67 scans in eleven patients with malignant pleural mesothelioma were reviewed and compared to those of chest CT findings. All patients had an abnormal thoracic Ga-67 accumulation. Six out of 11 showed a diffuse accumulation over the entire involved hemithorax and a localized uptake was shown in 5. A marked diffuse thickening of pleura in the absence of adequate gallium accumulation was observed in one patient. Two out of 11 had a reduction of gallium uptake after having combination chemotherapy. These results suggest that a diffusely increased uptake over the entire involved hemithorax is the most characteristic finding of Ga-67 scan in malignant pleural mesothelioma, and that Ga-67 scans may be helpful as a valuable indicator of the proper therapy. However, the superiority of Ga-67 scan to thoracic CT as a means of determining the extent of disease process could not be verified. (author)

  12. Does aspiration of bones and joints affect results of later bone scanning

    International Nuclear Information System (INIS)

    Canale, S.T.; Harkness, R.M.; Thomas, P.A.; Massie, J.D.

    1985-01-01

    To determine the effect, if any, of needle aspiration on /sup 99m/Tc bone scanning, three different areas of 15 dogs were first aspirated and then imaged with technetium bone scintigraphy. The hip joint was aspirated, the distal femoral metaphysis was drilled and aspirated, and the tibial periosteum was scraped with an 18- or 20-gauge needle. Varying amounts of trauma were inflicted to simulate varying difficulties at aspiration. /sup 99m/Tc bone scans were obtained from 5 h to 10 days later. There was no evidence of focal technetium uptake after any hip joint aspiration. This was consistent regardless of the amount of trauma inflicted or the time from aspiration to bone scanning. Metaphyseal cortical drilling and tibial periosteal scraping occasionally caused some focal uptake when scanning was delayed greater than 2 days. When osteomyelitis or pyarthrosis is clinically suspected, joint aspiration can be performed without fear of producing a false- positive bone scan

  13. Dose error analysis for a scanned proton beam delivery system

    International Nuclear Information System (INIS)

    Coutrakon, G; Wang, N; Miller, D W; Yang, Y

    2010-01-01

    All particle beam scanning systems are subject to dose delivery errors due to errors in position, energy and intensity of the delivered beam. In addition, finite scan speeds, beam spill non-uniformities, and delays in detector, detector electronics and magnet responses will all contribute errors in delivery. In this paper, we present dose errors for an 8 x 10 x 8 cm 3 target of uniform water equivalent density with 8 cm spread out Bragg peak and a prescribed dose of 2 Gy. Lower doses are also analyzed and presented later in the paper. Beam energy errors and errors due to limitations of scanning system hardware have been included in the analysis. By using Gaussian shaped pencil beams derived from measurements in the research room of the James M Slater Proton Treatment and Research Center at Loma Linda, CA and executing treatment simulations multiple times, statistical dose errors have been calculated in each 2.5 mm cubic voxel in the target. These errors were calculated by delivering multiple treatments to the same volume and calculating the rms variation in delivered dose at each voxel in the target. The variations in dose were the result of random beam delivery errors such as proton energy, spot position and intensity fluctuations. The results show that with reasonable assumptions of random beam delivery errors, the spot scanning technique yielded an rms dose error in each voxel less than 2% or 3% of the 2 Gy prescribed dose. These calculated errors are within acceptable clinical limits for radiation therapy.

  14. Iterative learning control with basis functions for media positioning in scanning inkjet printers

    NARCIS (Netherlands)

    Bolder, J.J.; Lemmen, B.P.; Koekebakker, S.H.; Oomen, T.A.E.; Bosgra, O.H.; Steinbuch, M.

    2012-01-01

    In printing systems, the positioning accuracy of the medium with respect to the print heads directly impacts print quality. In a regular document inkjet printer, the main task of the media positioning drive is to shift the medium after the printhead has finished a pass. Most media have the tendency

  15. Cerebral FDG-PET scanning abnormalities in optimally treated HIV patients

    DEFF Research Database (Denmark)

    Andersen, Ase B; Law, Ian; Krabbe, Karen S

    2010-01-01

    with no history of virological failure, a CD4 count above 200 x 106 cells/l and no other co-morbidities. The distribution of the regional cerebral metabolic rate of glucose metabolism was measured using fluorine-18-flourodeoxyglucose positron emission tomography (FDG-PET) scanning. The PET scans were evaluated...... in the relative metabolic rate of glucose. Compared to healthy subjects, the patients with abnormal FDG-PET scanning results had a shorter history of known HIV infection, fewer years on antiretroviral therapy and higher levels of circulating TNF alpha and IL-6 (p = 0.08). CONCLUSION: A large proportion...... of optimally treated HIV patients exhibit cerebral FDG-PET scanning abnormalities and elevated TNF alpha and IL-6 levels, which may indicate imminent neuronal damage. The neuroprotective effect of early ARV treatment should be considered in future prospective follow-up studies....

  16. The value of combined examination of serum CYFRA21-1 levels and bone scan in the diagnosis of bone metastasis in lung cancer

    International Nuclear Information System (INIS)

    Yu Jing; Wang Junhong; Zhengping

    2007-01-01

    Objective: To explore the value of combined examination of serum tumor markers CYFRA21-1 and bone scan in the diagnosis of bone metastasis in lung cancer. Methods: Bone scan and serum CYFRA21-1 levels (with CLIA) determination were performed in 138 patients with lung cancer and 56 patients with benign lung diseases. Results: The serum level of CYFRA21-1 were significantly higher in patients with bone metastasis than those in patients without bone metastasis. The levels were also higher in patients without bone metastasis than those in controls. Most patients with bone metastasis had positive results in bone scan (97.4%), only 2 of the 78 had negative bone scan but positive with CT or MRI. A few patients without bone metastasis and controls had positive bone scan results, caused by previous operation or injury. Conclusion: The combined detection of CYFRA21-1 and bone scan were valuable in the diagnosis of bone metastasis of lung cancer. (authors)

  17. [Diagnoses of rice nitrogen status based on characteristics of scanning leaf].

    Science.gov (United States)

    Zhu, Jin-Xia; Deng, Jin-Song; Shi, Yuan-Yuan; Chen, Zhu-Lu; Han, Ning; Wang, Ke

    2009-08-01

    In the present research, the scanner was adopted as the digital image sensor, and a new method to diagnose the status of rice based on image processing technology was established. The main results are as follows: (1) According to the analysis of relations between leaf percentage nitrogen contents and color parameter, the sensitive color parameters were abstracted as B, b, b/(r+g), b/r and b/g. The leaf position (vertical spatial variation) effects on leaf chlorophyll contents were investigated, and the third fully expanded leaf was selected as the diagnosis leaf. (2) Field ground data such as ASD were collected simultaneously. Then study on the relationships between scanned leaf color characteristics and hyperspectral was carried out. The results indicated that the diagnosis of nitrogen status based on the scanned color characteristic is able to partly reflect the hyperspectral properties. (3) The leaf color and shape features were intergrated and the model of diagnosing the status of rice was established with calculated at YIQ color system. The distinct accuracy of nitrogen status was as follows: N0: 74.9%; N1 : 52%; N2 : 84.7%; N3 : 75%. The preliminary study showed that the methodology has been proved successful in this study and provides the potential to monitor nitrogen status in a cost-effective and accurate way based on the scanned digital image. Although, some confusion exists, with rapidly increasing resolution of digital platform and development of digital image technology, it will be more convenient for larger farms that can afford to use mechanized systems for site-specific nutrient management. Moreover, deeper theory research and practice experiment should be needed in the future.

  18. An empirical Bayes method for updating inferences in analysis of quantitative trait loci using information from related genome scans.

    Science.gov (United States)

    Zhang, Kui; Wiener, Howard; Beasley, Mark; George, Varghese; Amos, Christopher I; Allison, David B

    2006-08-01

    Individual genome scans for quantitative trait loci (QTL) mapping often suffer from low statistical power and imprecise estimates of QTL location and effect. This lack of precision yields large confidence intervals for QTL location, which are problematic for subsequent fine mapping and positional cloning. In prioritizing areas for follow-up after an initial genome scan and in evaluating the credibility of apparent linkage signals, investigators typically examine the results of other genome scans of the same phenotype and informally update their beliefs about which linkage signals in their scan most merit confidence and follow-up via a subjective-intuitive integration approach. A method that acknowledges the wisdom of this general paradigm but formally borrows information from other scans to increase confidence in objectivity would be a benefit. We developed an empirical Bayes analytic method to integrate information from multiple genome scans. The linkage statistic obtained from a single genome scan study is updated by incorporating statistics from other genome scans as prior information. This technique does not require that all studies have an identical marker map or a common estimated QTL effect. The updated linkage statistic can then be used for the estimation of QTL location and effect. We evaluate the performance of our method by using extensive simulations based on actual marker spacing and allele frequencies from available data. Results indicate that the empirical Bayes method can account for between-study heterogeneity, estimate the QTL location and effect more precisely, and provide narrower confidence intervals than results from any single individual study. We also compared the empirical Bayes method with a method originally developed for meta-analysis (a closely related but distinct purpose). In the face of marked heterogeneity among studies, the empirical Bayes method outperforms the comparator.

  19. Laser scanning of a recirculation zone on the Bolund escarpment

    DEFF Research Database (Denmark)

    Mann, Jakob; Angelou, Nikolas; Sjöholm, Mikael

    2014-01-01

    Rapid variations in the height of the recirculation zone are measured with a scanning wind lidar over a small escarpment on the Bolund Peninsula. The lidar is essentially a continuous-wave laser Doppler anemometer with the capability of rapidly changing the focus distance and the beam direction....... The instrument measures the line-of-sight velocity 390 times per second and scans ten wind profiles from the ground up to seven meters per second. We observe a sharp interface between slow and fast moving fluid after the escarpment, and the interface is moving rapidly up and down. This implies that the position...

  20. Scanning control and data acquisition interface for a spectroscopy diagnostic

    International Nuclear Information System (INIS)

    Lopez-Callejas, R.; Galindo, S.; Benitez-Read, J.S.; Pacheco-Sotelo, J.; Longoria-Gandara, L.C.; Valencia-Alvarado, R.

    2001-01-01

    This work presents the design of a PC supported interface unit that improves the operation of a mechanically driven Czerny-Turner monochromator to the point of meeting the conditions required to be useful in wavelength separation and spectrum analysis for breakdown and conditioning discharges in plasma physics diagnostics. The PC supported interface verifies and sets the position and scan range of the instrument scanning drive. The interface consists of a microcontroller and its associated circuitry. The microcontroller is also used as a data acquisition and data manipulation element. An example of obtained spectra illustrating the instrument greatly improved performance is presented

  1. Head-positioning scintillation camera and head holder therefor

    International Nuclear Information System (INIS)

    Kay, T.D.

    1976-01-01

    A holder for immobilizing the head of a patient undergoing a vertex brain scan by a Gamma Scintillation Camera is described. The holder has a uniquely designed shape capable of comfortably supporting the head. In addition, this holder can be both adjustably and removably utilized in combination with the scintillation camera so as to enable the brain scan operation to take place while the patient is in the seated position

  2. Scanning tunneling microscopy II further applications and related scanning techniques

    CERN Document Server

    Güntherodt, Hans-Joachim

    1995-01-01

    Scanning Tunneling Microscopy II, like its predecessor, presents detailed and comprehensive accounts of the basic principles and broad range of applications of STM and related scanning probe techniques. The applications discussed in this volume come predominantly from the fields of electrochemistry and biology. In contrast to those described in STM I, these studies may be performed in air and in liquids. The extensions of the basic technique to map other interactions are described in chapters on scanning force microscopy, magnetic force microscopy, and scanning near-field optical microscopy, together with a survey of other related techniques. Also described here is the use of a scanning proximal probe for surface modification. Together, the two volumes give a comprehensive account of experimental aspects of STM. They provide essential reading and reference material for all students and researchers involved in this field. In this second edition the text has been updated and new methods are discussed.

  3. Value of liver scan in the follow-up study of patients with adenocarcinoma of the colon and rectum

    International Nuclear Information System (INIS)

    Cedermark, B.J.; Schultz, S.S.; Bakshi, S.; Parthasarathy, K.L.; Mittelman, A.; Evans, J.T.

    1977-01-01

    Seventy consecutive patients with adenocarcinoma of the colon and rectum had a liver scan followed by surgical exploration of the liver. Preoperatively, blood chemistry studies were done in addition to palpation of the abdomen. Surgical findings were correlated to results of the liver scans, function tests and palpation of the liver. The overall concordance of liver scans with surgical findings was 78 percent. Thirty percent had false-positive results and 15 percent, false-negative results. The correlation of the liver scan with surgical findings was improved with increasing extent of metastases. When less than 25 percent of the liver was replaced by tumor, there was a random correlation of scan to surgical findings. By combining liver scans and liver function tests, metastases could be predicted with increased reliability only in patients who had severe metastatic disease of the liver. It is strongly recommended that patients with liver scans suggestive of metastatic disease and with most liver function tests within normal limits undergo exploration to establish the diagnosis. Exploratory laparotomy seems to be the only way to avoid chemotherapeutic treatment of patients with false-positive scans and still allow detection and treatment of metastases to the liver to occur at earlier stages

  4. USE OF PLASTIC MATERIAL AND TRIPLE SCAN IN THE PREPARATION OF SURGICAL GUIDES FOR THE DENTAL IMPLANT TREATMENT-CASE REPORT

    Directory of Open Access Journals (Sweden)

    Rosen Borisov

    2016-09-01

    Full Text Available The use of surgical guides in implant treatment increases the accuracy of the dental implant positioning compared with manual methods. Regardless of how they are made, deviations of implants from their intended position are established in all kinds of surgical guides. This article considers the use of plastic material and new scanning technique for the production of CAD/CAM surgical guides that aim to overcome the deficiencies of the currently applied technologies in the production of surgical guides. Materials and methods: The study shows the techniques used to overcome degraded by metal artifacts CBCT images in implant treatment of patients with partial edentulism, and located medially to the defect metal-ceramic crowns. When planning implant treatment, a triple scan method has been implied. At the beginning, CBCT scan of the patient with a silicone impression material is made in the zone of interest. Secondly, CBCT scan only of the silicon impression is made, and thirdly - intraoral scanning of the patient with an intraoral scanner. Virtual analogues have been created of images from the three scans and have been repositioned one over another; as thereby an intraoral image have been accurately positioned over the CBCT image of the patient. Virtual planning of the implant positioning has been performed, and a model of surgical guide has been made for their placement. The guide has been printed with an SLA 3D printer technology of photopolymer with dualistic characteristics-rigid in the working part and plastic in the fixing part. Through it, implants have been placed to the treatment planning. Postoperative CBCT has been done on the patient to measure the implant deviation to their position in the treatment planning. Results: Axes angular deviation of the planned and placed implants has not been established. Average linear displacement of 240 μ (+/- 40 μ has been found. Conclusions: Using the triple scan method is possible to overcome the

  5. Gallium scanning in differentiating malignant from benign asbestos-related pleural disease

    International Nuclear Information System (INIS)

    Teirstein, A.S.; Chahinian, P.; Goldsmith, S.J.; Sorek, M.

    1986-01-01

    In order to assess the utility of 67gallium citrate in delineating malignant pleural mesothelioma from benign asbestos-related pleural disease, 49 patients with malignant mesothelioma and 16 with benign asbestos-related pleural disease were studied. Seven patients with malignant mesothelioma had no history of asbestos exposure, while the remaining 58 patients were exposed. Forty-three of the 49 patients (88%) with malignant mesothelioma had a positive 67gallium scan including 36 of the 42 (86%) patients with asbestos exposure and all 7 patients without a history of asbestos exposure. Three of 16 patients (19%) with benign asbestos-related pleural disease had a positive scan. 67Gallium radionuclide imaging is nonspecific but may be valuable in noninvasive monitoring of asbestos-exposed populations, which have a high risk for the late development of benign and/or malignant pleural disease

  6. Prognosis of ischemic heart disease based on pyrophosphate scan of myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Duska, F [Karlova Univ., Hradec Kralove (Czechoslovakia). Lekarska Fakulta

    1982-11-01

    A brief survey is given of the present knowledge of the problems, based on literary data. Pyrophosphate myocardial scan is an important examination in establishing the diagnosis of acute myocardial infarction and some other myocardial diseases. Apart from this, it is of great importance in determining the prognosis. In the early phase of the disease, an apparently worse prognosis is found in patients with extensive lesion, and in those with an infarction intensively accumulating the radiopharmaceutical. In a certain number of infarctions, scintigraphic examination is positive over several months; usually the radiopharmaceutical disappears within two weeks. Patients with long-persisting positivity have a markedly worse prognosis. On the basis of early and late heart scan, it is thus possible to estimate the future fate of patients w+th ischemic heart disease. Large and long-persisting lesions serve as a warning for the physician.

  7. SU-F-T-213: Commissioning Results of the Prototype Active Scanning Irradiation System of Korea Heavy Ion Medical Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Kim, C; Seduk, J; Yang, T [Korea Institute of Radiological And Medical Sciences, Seoul, Seoul (Korea, Republic of)

    2016-06-15

    Purpose: A prototype actives scanning beam delivery system was designed, manufactured and installed as a part of the Korea Heavy Ion Medical Accelerator Project. The prototype system includes the most components for steering, modulating, detecting incident beam to patient. The system was installed in MC-50 cyclotron beam line and tested to extract the normal operation conditions. Methods: The commissioning process was completed by using 45 MeV of proton beam. To measure the beam position accuracy along the scanning magnet power supply current, 25 different spots were scanning and measured. The scanning results on GaF film were compared with the irradiation plan. Also, the beam size variation and the intensity reduction using range shifter were measured and analyzed. The results will be used for creating a conversion factors for asymmetric behavior of scanning magnets and a dose compensation factor for longitudinal direction. Results: The results show asymmetry operations on both scanning × and y magnet. In case of scanning magnet × operation, the current to position conversion factors were measured 1.69 mm/A for positive direction and 1.74 mm/A for negative direction. The scanning magnet y operation shows 1.38mm/A and 1.48 mm/A for both directions. The size of incoming beam which was 18 mm as sigma becomes larger up to 55 mm as sigma while using 10 mm of the range shifter plate. As the beam size becomes large, the maximum intensity of the was decreased. In case of using 10 mm of range shifter, the maximum intensity was only 52% compared with no range shifter insertion. Conclusion: For the appropriate operation of the prototype active scanning system, the commissioning process were performed to measure the beam characteristics variation. The obtained results would be applied on the irradiation planning software for more precise dose delivery using the active scanning system.

  8. Acquiring 4D thoracic CT scans using a multislice helical method

    International Nuclear Information System (INIS)

    Keall, P J; Starkschall, G; Shukla, H; Forster, K M; Ortiz, V; Stevens, C W; Vedam, S S; George, R; Guerrero, T; Mohan, R

    2004-01-01

    Respiratory motion degrades anatomic position reproducibility during imaging, necessitates larger margins during radiotherapy planning and causes errors during radiation delivery. Computed tomography (CT) scans acquired synchronously with the respiratory signal can be used to reconstruct 4D CT scans, which can be employed for 4D treatment planning to explicitly account for respiratory motion. The aim of this research was to develop, test and clinically implement a method to acquire 4D thoracic CT scans using a multislice helical method. A commercial position-monitoring system used for respiratory-gated radiotherapy was interfaced with a third generation multislice scanner. 4D cardiac reconstruction methods were modified to allow 4D thoracic CT acquisition. The technique was tested on a phantom under different conditions: stationary, periodic motion and non-periodic motion. 4D CT was also implemented for a lung cancer patient with audio-visual breathing coaching. For all cases, 4D CT images were successfully acquired from eight discrete breathing phases, however, some limitations of the system in terms of respiration reproducibility and breathing period relative to scanner settings were evident. Lung mass for the 4D CT patient scan was reproducible to within 2.1% over the eight phases, though the lung volume changed by 20% between end inspiration and end expiration (870 cm 3 ). 4D CT can be used for 4D radiotherapy, respiration-gated radiotherapy, 'slow' CT acquisition and tumour motion studies

  9. Gwyscan: a library to support non-equidistant scanning probe microscope measurements

    International Nuclear Information System (INIS)

    Klapetek, Petr; Grolich, Petr; Valtr, Miroslav; Yacoot, Andrew; Nečas, David

    2017-01-01

    We present a software library and related methodology for enabling easy integration of adaptive step (non-equidistant) scanning techniques into metrological scanning probe microscopes or scanning probe microscopes where individual x , y position data are recorded during measurements. Scanning with adaptive steps can reduce the amount of data collected in SPM measurements thereby leading to faster data acquisition, a smaller amount of data collection required for a specific analytical task and less sensitivity to mechanical and thermal drift. Implementation of adaptive scanning routines into a custom built microscope is not normally an easy task: regular data are much easier to handle for previewing (e.g. levelling) and storage. We present an environment to make implementation of adaptive scanning easier for an instrument developer, specifically taking into account data acquisition approaches that are used in high accuracy microscopes as those developed by National Metrology Institutes. This includes a library with algorithms written in C and LabVIEW for handling data storage, regular mesh preview generation and planning the scan path on basis of different assumptions. A set of modules for Gwyddion open source software for handling these data and for their further analysis is presented. Using this combination of data acquisition and processing tools one can implement adaptive scanning in a relatively easy way into an instrument that was previously measuring on a regular grid. The performance of the presented approach is shown and general non-equidistant data processing steps are discussed. (paper)

  10. Gwyscan: a library to support non-equidistant scanning probe microscope measurements

    Science.gov (United States)

    Klapetek, Petr; Yacoot, Andrew; Grolich, Petr; Valtr, Miroslav; Nečas, David

    2017-03-01

    We present a software library and related methodology for enabling easy integration of adaptive step (non-equidistant) scanning techniques into metrological scanning probe microscopes or scanning probe microscopes where individual x, y position data are recorded during measurements. Scanning with adaptive steps can reduce the amount of data collected in SPM measurements thereby leading to faster data acquisition, a smaller amount of data collection required for a specific analytical task and less sensitivity to mechanical and thermal drift. Implementation of adaptive scanning routines into a custom built microscope is not normally an easy task: regular data are much easier to handle for previewing (e.g. levelling) and storage. We present an environment to make implementation of adaptive scanning easier for an instrument developer, specifically taking into account data acquisition approaches that are used in high accuracy microscopes as those developed by National Metrology Institutes. This includes a library with algorithms written in C and LabVIEW for handling data storage, regular mesh preview generation and planning the scan path on basis of different assumptions. A set of modules for Gwyddion open source software for handling these data and for their further analysis is presented. Using this combination of data acquisition and processing tools one can implement adaptive scanning in a relatively easy way into an instrument that was previously measuring on a regular grid. The performance of the presented approach is shown and general non-equidistant data processing steps are discussed.

  11. Spiral scan long object reconstruction through PI line reconstruction

    International Nuclear Information System (INIS)

    Tam, K C; Hu, J; Sourbelle, K

    2004-01-01

    The response of a point object in a cone beam (CB) spiral scan is analysed. Based on the result, a reconstruction algorithm for long object imaging in spiral scan cone beam CT is developed. A region-of-interest (ROI) of the long object is scanned with a detector smaller than the ROI, and a portion of it can be reconstructed without contamination from overlaying materials. The top and bottom surfaces of the ROI are defined by two sets of PI lines near the two ends of the spiral path. With this novel definition of the top and bottom ROI surfaces and through the use of projective geometry, it is straightforward to partition the cone beam image into regions corresponding to projections of the ROI, the overlaying objects or both. This also simplifies computation at source positions near the spiral ends, and makes it possible to reduce radiation exposure near the spiral ends substantially through simple hardware collimation. Simulation results to validate the algorithm are presented

  12. Bone scan and serum CA 15-3 in bone metastasis in breast cancer

    International Nuclear Information System (INIS)

    Mendoza, G.; Cano, R.; Morales, R.; Guzman, C.

    1996-01-01

    CA 15-3 is a tumor marker useful in evolution control of breast cancer, being the serum levels trend the most important parameter. The purpose of this study was to report our experience and show the concordance of bone scan and CA 15-3 in patients with breast cancer attending the Breast and Bone Department of INEN from June to December 1993. One hundred patients had serum CA 15-3 quantification between June and December of 1993 in Nuclear Medicine Center (Peruvian Institute of Nuclear Energy and National Institute of Neoplasic Diseases). We selected 52 patients which simultaneously had a bone scan performed. Patients age ranged from 21 to 67 years (media of 44,57 years). 99m Tc methylenediphosphonate produced by IPEN was the radiopharmaceutical employed. A GE AZS-400 gamma camera was utilized to obtain the bone scans. Ca 15-5 quantification was performed with ELSA-CA 15-3 (CIS bio France) IRMA kit. Bone scan and CA 15-3 media of 17,06 U/ml (DS 15,4). Eight patients had a positive bone scan with a CA 15-3 media of 41,6 U/ml (SD 23,0). CA 15-3 levels ranged between 4,6 and 96,0 U/ml in the first group and 10,1 U/ml to 75,0 U/ml in the second group. Using a cut-off point of 30 U/ml the sensitivity of CA 15-3 was 62,5% and the specificity 93,2% respectively. Mean CA 15-3 values of the negative and positive bone scan groups were significantly different (p=0,0361). The high negative predictive value of CA 15-3 may help to establish which patients will benefit from bone scan procedure. (authors) 42 refs., 2 tabs

  13. Bone scanning with technetium /sup 99m/Tc polyphosphate in tuberculous osteomyelitis

    Energy Technology Data Exchange (ETDEWEB)

    Fanning, A; Dierich, H; Lentle, B

    1974-09-01

    Bone scans in 7 patients with tuberculosis have indicated bony involvement in 3. This was unsuspected in 2 and in all 3 radiographic correlation has been obtained. The present ready availability of more modern bone scanning agents and their safety is important to remember. They provide an elegant and sensitive, if non-specific, index of bone disease.

  14. IMPROVED REAL-TIME SCAN MATCHING USING CORNER FEATURES

    Directory of Open Access Journals (Sweden)

    H. A. Mohamed

    2016-06-01

    Full Text Available The automation of unmanned vehicle operation has gained a lot of research attention, in the last few years, because of its numerous applications. The vehicle localization is more challenging in indoor environments where absolute positioning measurements (e.g. GPS are typically unavailable. Laser range finders are among the most widely used sensors that help the unmanned vehicles to localize themselves in indoor environments. Typically, automatic real-time matching of the successive scans is performed either explicitly or implicitly by any localization approach that utilizes laser range finders. Many accustomed approaches such as Iterative Closest Point (ICP, Iterative Matching Range Point (IMRP, Iterative Dual Correspondence (IDC, and Polar Scan Matching (PSM handles the scan matching problem in an iterative fashion which significantly affects the time consumption. Furthermore, the solution convergence is not guaranteed especially in cases of sharp maneuvers or fast movement. This paper proposes an automated real-time scan matching algorithm where the matching process is initialized using the detected corners. This initialization step aims to increase the convergence probability and to limit the number of iterations needed to reach convergence. The corner detection is preceded by line extraction from the laser scans. To evaluate the probability of line availability in indoor environments, various data sets, offered by different research groups, have been tested and the mean numbers of extracted lines per scan for these data sets are ranging from 4.10 to 8.86 lines of more than 7 points. The set of all intersections between extracted lines are detected as corners regardless of the physical intersection of these line segments in the scan. To account for the uncertainties of the detected corners, the covariance of the corners is estimated using the extracted lines variances. The detected corners are used to estimate the transformation parameters

  15. Cooperative scans

    NARCIS (Netherlands)

    M. Zukowski (Marcin); P.A. Boncz (Peter); M.L. Kersten (Martin)

    2004-01-01

    textabstractData mining, information retrieval and other application areas exhibit a query load with multiple concurrent queries touching a large fraction of a relation. This leads to individual query plans based on a table scan or large index scan. The implementation of this access path in most

  16. Relative value of thallium-201 and iodine-131 scans in the detection of recurrence or distant metastasis of well differentiated thyroid carcinoma

    International Nuclear Information System (INIS)

    Lin Jen-Der; Weng Hsiao-Fen; Lu Wen-Tsoung; Kao Pan-Fu; Huang Miau-Ju

    1998-01-01

    Radioactive iodine ( 131 I) has been found to be more sensitive and more specific than thallium-201 for the detection of distant metastases and thyroid remnants in the neck in cases of well-differentiated thyroid carcinoma. 201 Tl has been deemed particularly useful in localizing metastases or recurrence in patients with a negative 131 I scan and abnormal levels of serum thyroglobulin (Tg). This study aimed to: (1) determine the value of 201 Tl imaging in localizing metastases or recurrence in patients with well-differentiated thyroid carcinoma, and (2) evaluate the false-positive and false-negative results of 131 I and 201 Tl scintigraphy. Sixty-two thyroid remnant ablated patients who underwent simultaneous postoperative 201 Tl and 131 I scans and and serum Tg determinations were evaluated. Fifty patients had papillary thyroid carcinomas and 12 had follicular thyroid carcinomas. 201 Tl imaging was performed before the 131 I studies. Of the 62 patients who underwent 201 Tl imaging studies, 24 were found to have positive results, with local recurrence or distant metastases. Patients with positive results in the 201 Tl imaging studies tended to be older, were mor often male, had higher Tg levels and had a higher recurrence rate. Of these 24 patients, ten had negative diagnostic or therapeutic 131 I scans. Concurrently, serum Tg levels were less than 5 ng/ml in five of these ten patients. Three patients were deemed false positive by 201 Tl scans; one had a parotid tumour, one a periodontal abscess and one lung metastasis. Among the 38 patients with negative 201 Tl scans, 11 had positive findings on 131 I scans. Three had distant metastases: two with lung metastases and one with bone metastases. Patients with false-positive results on 131 I scans included those with biliary tract stones, ovarian cysts, and breast secretion. Of the 27 patients with negative 201 Tl and 131 I scans, 15 had elevated serum Tg levels. Among these, local recurrence followed by lung

  17. Remote Sensing of Cloud Top Heights Using the Research Scanning Polarimeter

    Science.gov (United States)

    Sinclair, Kenneth; van Diedenhoven, Bastiaan; Cairns, Brian; Yorks, John; Wasilewski, Andrzej

    2015-01-01

    Clouds cover roughly two thirds of the globe and act as an important regulator of Earth's radiation budget. Of these, multilayered clouds occur about half of the time and are predominantly two-layered. Changes in cloud top height (CTH) have been predicted by models to have a globally averaged positive feedback, however observational changes in CTH have shown uncertain results. Additional CTH observations are necessary to better and quantify the effect. Improved CTH observations will also allow for improved sub-grid parameterizations in large-scale models and accurate CTH information is important when studying variations in freezing point and cloud microphysics. NASA's airborne Research Scanning Polarimeter (RSP) is able to measure cloud top height using a novel multi-angular contrast approach. RSP scans along the aircraft track and obtains measurements at 152 viewing angles at any aircraft location. The approach presented here aggregates measurements from multiple scans to a single location at cloud altitude using a correlation function designed to identify the location-distinct features in each scan. During NASAs SEAC4RS air campaign, the RSP was mounted on the ER-2 aircraft along with the Cloud Physics Lidar (CPL), which made simultaneous measurements of CTH. The RSPs unique method of determining CTH is presented. The capabilities of using single and combinations of channels within the approach are investigated. A detailed comparison of RSP retrieved CTHs with those of CPL reveal the accuracy of the approach. Results indicate a strong ability for the RSP to accurately identify cloud heights. Interestingly, the analysis reveals an ability for the approach to identify multiple cloud layers in a single scene and estimate the CTH of each layer. Capabilities and limitations of identifying single and multiple cloud layers heights are explored. Special focus is given to sources of error in the method including optically thin clouds, physically thick clouds, multi

  18. Special raster scanning for reduction of charging effects in scanning electron microscopy.

    Science.gov (United States)

    Suzuki, Kazuhiko; Oho, Eisaku

    2014-01-01

    A special raster scanning (SRS) method for reduction of charging effects is developed for the field of SEM. Both a conventional fast scan (horizontal direction) and an unusual scan (vertical direction) are adopted for acquiring raw data consisting of many sub-images. These data are converted to a proper SEM image using digital image processing techniques. About sharpness of the image and reduction of charging effects, the SRS is compared with the conventional fast scan (with frame-averaging) and the conventional slow scan. Experimental results show the effectiveness of SRS images. By a successful combination of the proposed scanning method and low accelerating voltage (LV)-SEMs, it is expected that higher-quality SEM images can be more easily acquired by the considerable reduction of charging effects, while maintaining the resolution. © 2013 Wiley Periodicals, Inc.

  19. A review of patient dose and optimisation methods in adult and paediatric CT scanning

    International Nuclear Information System (INIS)

    Dougeni, E.; Faulkner, K.; Panayiotakis, G.

    2012-01-01

    Highlights: ► CT scanning frequency has grown with the development of new clinical applications. ► Up to 32-fold dose variation was observed for similar type of procedures. ► Scanning parameters should be optimised for patient size and clinical indication. ► Cancer risks knowledge amongst physicians of certain specialties was poor. ► A significant number of non-indicated CT scans could be eliminated. - Abstract: An increasing number of publications and international reports on computed tomography (CT) have addressed important issues on optimised imaging practice and patient dose. This is partially due to recent technological developments as well as to the striking rise in the number of CT scans being requested. CT imaging has extended its role to newer applications, such as cardiac CT, CT colonography, angiography and urology. The proportion of paediatric patients undergoing CT scans has also increased. The published scientific literature was reviewed to collect information regarding effective dose levels during the most common CT examinations in adults and paediatrics. Large dose variations were observed (up to 32-fold) with some individual sites exceeding the recommended dose reference levels, indicating a large potential to reduce dose. Current estimates on radiation-related cancer risks are alarming. CT doses account for about 70% of collective dose in the UK and are amongst the highest in diagnostic radiology, however the majority of physicians underestimate the risk, demonstrating a decreased level of awareness. Exposure parameters are not always adjusted appropriately to the clinical question or to patient size, especially for children. Dose reduction techniques, such as tube-current modulation, low-tube voltage protocols, prospective echocardiography-triggered coronary angiography and iterative reconstruction algorithms can substantially decrease doses. An overview of optimisation studies is provided. The justification principle is discussed along

  20. Pulmonary embolic disease: roles of angiography and lung scanning in diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, D C; Tyson, J W; Johnsrude, I S; Wilkinson, Jr, R H

    1975-06-01

    The definitive diagnosis of pulmonary embolism remains difficult despite recent advances in nuclear medicine and angiography. In 10% of a selected series of 145 patients a negative chest x-ray and a positive lung scan was associated with no arteriographic evidence of pulmonary emboli. A normal perfusion lung scan excludes significant pulmonary embolism. When pulmonary arteriography is necessary, a biplane selective pulmonary angiogram should be performed and subselective injections may be required. Pulmonary arteriography is less of a threat to a patient suspected of having pulmonary embolic disease than inappropriate treatment.

  1. Scanning-beam digital x-ray (SBDX) technology for interventional and diagnostic cardiac angiography

    International Nuclear Information System (INIS)

    Speidel, Michael A.; Wilfley, Brian P.; Star-Lack, Josh M.; Heanue, Joseph A.; Van Lysel, Michael S.

    2006-01-01

    The scanning-beam digital x-ray (SBDX) system is designed for x-ray dose reduction in cardiac angiographic applications. Scatter reduction, efficient detection of primary x-rays, and an inverse beam geometry are the main components of the entrance dose reduction strategy. This paper reports the construction of an SBDX prototype, image reconstruction techniques, and measurements of spatial resolution and x-ray output. The x-ray source has a focal spot that is electronically scanned across a large-area transmission target. A multihole collimator beyond the target defines a series of x-ray beams directed at a distant small-area detector array. The prototype has a 23 cmx23 cm target, 100x100 focal spot positions, and a 5 cmx5 cm CdTe detector positioned 150 cm from the target. With this nonmechanical method of beam scanning, patient images with low detected scatter are generated at up to 30 frame/s. SBDX data acquisition is tomosynthetic. The prototype simultaneously reconstructs 16 planes spaced throughout the cardiac volume using shift-and-add backprojection. Image frames analogous to conventional projection images are generated with a multiplane compositing algorithm. Single-plane versus multiplane reconstruction of contrast-filled coronary arteries is demonstrated with images of the porcine heart. Phantom and porcine imaging studies show multiplane reconstruction is practicable under clinically realistic levels of patient attenuation and cardiac motion. The modulation transfer function for an in-plane slit at mechanical isocenter measured 0.41-0.56 at 1 cycle/mm, depending on the detector element to image pixel interpolation technique. Modeling indicates that desired gains in spatial resolution are achievable by halving the detector element width. The x-ray exposure rate 15 cm below isocenter, without table or patient in the beam, measured 11.5 R/min at 120 kVp, 24.3 kWp and 3.42 R/min at 70 kVp, 14.2 kWp

  2. Diagnostic efficacy and pitfalls of a 64-raw multislice computed tomography scan for mild head injuries in children

    International Nuclear Information System (INIS)

    Matsumoto, Yoshihisa; Nawashiro, Hiroshi; Uozumi, Youichi

    2010-01-01

    The aim of this study is to analyze the usefulness of 64-raw multislice computed tomography (CT) scans and bone images of three-dimensional CT (3D-CT) scans for evaluation of mild head injuries in children. Thirteen children (9 boys and 4 girls, less than or equal to 15 years old) with mild head injury were included in the study. Head CT scans obtained within 24 hours after injury. All children had no episodes of loss of consciousness, amnesia, epilepsy, vomiting, and no neurological abnormality on arrival at hospital. We detected 9 positive findings on CT scans, which looked like fracture lines at the frontal bone in 7 cases. The bone images of CT axial views revealed a true fracture in one case in which a skull X-ray could not demonstrate a fracture line, but, other positive findings turned out to be a diploic vein surrounded by a thin bone cortex. All false positive findings were detected in the patients under the age of 6. By the 3D-reconstructive CT scan, it is easier to detect not only the intracranial lesions but also the cranial fracture. But, the diploic vein is apt to be misdiagnosed as the fracture line, especially in patients under the age of 6. (author)

  3. Prospective evaluation of the super scan of metabolic bone disease (abstract)

    International Nuclear Information System (INIS)

    Khan, A.U.; Ahmad, S.; Khan, A.A.; Khan, S.M.; Rauf, M.

    1999-01-01

    A total of 27 cases (23 females and 4 males) having super scan of metabolic bone disease were prospectively evaluated over a period of 2 years (Jan. 1997 to Dec. 1998) at the Nuclear Medicine Department (NMD), institute of Radiotherapy and Nuclear Medicine (IRNUM), Peshawar to identify various causes for the super scan picture on Tc-99m MDP bone scintigraphy in our clinical environment. After the three observer confirmation of the bone scan, the serum calcium and Parathyroid Hormone (PTH) estimation was done. The patients having serum PTH greater than 250 Pg/L under went two phase Parathyroid MIBI Scintigraphy 2PP MIBI scan) for the detection of parathyroid adenoma. The patients having positive scans for parathyroid Adenoma were subjected to surgery and histopathological confirmation was obtained. Selected cases under went a trial of deport preparation of vitamin D3 calcium supplementation. The final diagnosis of 16 patients was osteomalacia (59%), six patients had histopathologically confirmed parathyroid adenoma (22.2%), one case each was that of toxic thyroid adenoma (3.7%) and chronic renal failure (3.7%). In three cases the final diagnosis was not reached (11.21%). Osteomalacia and parathyroid adenoma are the two most common causes for the super scan picture on bone scintigraphy. (author)

  4. Optical nonlinearity of organic dyes as studied by Z-scan and ...

    Indian Academy of Sciences (India)

    Unknown

    Keywords. Excited state absorption; Z-scan; nonlinear refractive index; excited .... The σes value can be determined with the help of three and four level .... laser pulse the molecules in the thermal equilibrium position of first excited state (level 2.

  5. Consecutive Renal Scanning with {sup 131}I And {sup 203}Hg in Obstructive Uropathy

    Energy Technology Data Exchange (ETDEWEB)

    Poshyachinda, V. [Chulalongkorn Hospital, Bangkok (Thailand)

    1969-05-15

    Two patients with obstructive uropathy were scanned after injections of {sup 131}I sodium orthoiodohippurate (OlH) and {sup 203}Hg chlormerodrin. The {sup 131}I OIH scan was performed 30 min after the injection with the patient in the prone position. The {sup 203}Hg chlormerodrin was injected as soon as a negligible amount of {sup 131}I OIH was detected over the kidney, and the patient was scanned again 30 min later. A third patient and a normal subject were scanned 20 min after the simultaneous injection of {sup 131}I OIH and {sup 203}Hg chlormerodrin. Three scans with different analyser settings were done in sequence. The first scan was done with a window setting for {sup 131}I, and the second scan included both {sup 131}I and {sup 203}Hg; in the third scan, the analyser was set for {sup 203}Hg only. Evidence of hydronephroses, hydroureter and the residual functioning renal tissue were demonstrated by this scanning technique. The intravenous pyelograms in all three cases had failed to give satisfactory results. The simultaneous injection technique was found advantageous over the separate injection technique. (author)

  6. Diagnostic I-131 scintigraphy in patients with differentiated thyroid cancer. No additional value of higher scan dose

    International Nuclear Information System (INIS)

    Phan, T.T.H.; Tol, K.M. van; Links, T.P.; Piers, D.A.; Vries, E.G.E. de; Dullaart, R.P.F.; Jager, P.L.

    2004-01-01

    After initial treatment with total thyroidectomy and radio iodine ablation, most follow-up protocols for patients with differentiated thyroid carcinoma contain cyclic diagnostic I-131 imaging and serum thyroglobulin (Tg) measurements. The applied diagnostic I-131 doses vary between 37 and 370 MBq. The aim of this study was to determine the yield of a diagnostic scan with 370 MBq I-131 in patients with a negative diagnostic scan with 74 MBq I-131. Retrospective evaluation of 158 patients who received a high-dose diagnostic scan with 370 MBq I-131 because of a negative low-dose diagnostic scan with 74 MBq I-131. Special attention was paid to the patients with positive high-dose diagnostic scanning and undetectable serum Tg levels after thyroid hormone withdrawal. In 127 (80%) of patients the 370 MBq I-131 scan was negative, just like the preceding low-dose scan. In 31 (20%) of patients abnormal uptake was present on the 370 MBq diagnostic scan. In 19 of these 31 patients serum Tg was undetectable. In 15/19 the high-dose diagnostic scan proved either false positive or demonstrated clinically irrelevant minor ablation rests. In only four patients (2.5%) did the high-dose diagnostic scans reveal possibly relevant uptake caused by residual differentiated thyroid cancer. In 98% of patients a 370 MBq dose of I-131 for diagnostic whole-body scintigraphy (WBS) had no additional value. The combination of a low-dose diagnostic I-131 scan using only 74 MBq combined with a serum Tg level measurement proved sufficient for correct clinical decision making regarding whether the patient requires additional I-131 therapy. (authors)

  7. Scanning a DNA molecule for bound proteins using hybrid magnetic and optical tweezers.

    Directory of Open Access Journals (Sweden)

    Marijn T J van Loenhout

    Full Text Available The functional state of the genome is determined by its interactions with proteins that bind, modify, and move along the DNA. To determine the positions and binding strength of proteins localized on DNA we have developed a combined magnetic and optical tweezers apparatus that allows for both sensitive and label-free detection. A DNA loop, that acts as a scanning probe, is created by looping an optically trapped DNA tether around a DNA molecule that is held with magnetic tweezers. Upon scanning the loop along the λ-DNA molecule, EcoRI proteins were detected with ~17 nm spatial resolution. An offset of 33 ± 5 nm for the detected protein positions was found between back and forwards scans, corresponding to the size of the DNA loop and in agreement with theoretical estimates. At higher applied stretching forces, the scanning loop was able to remove bound proteins from the DNA, showing that the method is in principle also capable of measuring the binding strength of proteins to DNA with a force resolution of 0.1 pN/[Formula: see text]. The use of magnetic tweezers in this assay allows the facile preparation of many single-molecule tethers, which can be scanned one after the other, while it also allows for direct control of the supercoiling state of the DNA molecule, making it uniquely suitable to address the effects of torque on protein-DNA interactions.

  8. CT Scanning in Identification of Sheep Cystic Echinococcosis.

    Science.gov (United States)

    Mao, Rui; Qi, Hongzhi; Pei, Lei; Hao, Jie; Dong, Jian; Jiang, Tao; Ainiwaer, Abudula; Shang, Ge; Xu, Lin; Shou, Xi; Zhang, Songan; Wu, Ge; Lu, Pengfei; Bao, Yongxing; Li, Haitao

    2017-01-01

    We aim to determine the efficiency of CT in identification of cystic echinococcosis in sheep. Fifty-three sheep with liver cysts confirmed by ultrasonography were subject to CT scan to evaluate the number, size, and type of the cysts in liver and lung, confirmed using necropsy. The correlation of numbers between liver cysts and lung cysts was calculated using Pearson analysis. Necropsy indicated a 98% consensus on size, location, number, and activity compared with CT scan. The viable cysts were 53.1% and 50.6% in the liver and lung, respectively. Among the cysts in liver, 35.5%, 9.5%, 5.7%, 10.2%, and 39.1% were Types CE1, CE2, CE3, CE4, and CE5, respectively. The cysts in the lungs, 17.4%, 26.9%, 12.1%, 11.6%, and 32.1%, were Types CE1, CE2, CE3, CE4, and CE5, respectively. A significant correlation was noticed between the number of cysts in liver and those in lung ( R = 0.770, P < 0.001). CT scan is a suitable tool in determining the size and type of cystic hydatid cysts in both liver and lung of sheep. A significant correlation was noticed between the numbers in liver and lung, indicating that lung infection was likely due to the expansion of liver cyst burden pressure.

  9. Flash Glucose Monitoring: Differences Between Intermittently Scanned and Continuously Stored Data.

    Science.gov (United States)

    Pleus, Stefan; Kamecke, Ulrike; Link, Manuela; Haug, Cornelia; Freckmann, Guido

    2018-03-01

    The flash glucose monitoring system FreeStyle Libre (Abbott Diabetes Care Ltd., Witney, UK) measures interstitial glucose concentrations and continuously stores measurement values every 15 minutes. To obtain a current glucose reading, users have to scan the sensor with the reader. In a clinical trial, 5% of the scanned data showed relative differences of more than ±10% compared with continuously stored data points (median -0.5%). Such differences might impact results of studies using this system. It should be indicated whether scanned or continuously stored data were used for analyses. Health care professionals might have to differentiate between data reports from clinical software and the scanned data their patients are provided with. Additional information on these differences and their potential impact on therapeutic decisions would be helpful.

  10. Error analysis of terrestrial laser scanning data by means of spherical statistics and 3D graphs.

    Science.gov (United States)

    Cuartero, Aurora; Armesto, Julia; Rodríguez, Pablo G; Arias, Pedro

    2010-01-01

    This paper presents a complete analysis of the positional errors of terrestrial laser scanning (TLS) data based on spherical statistics and 3D graphs. Spherical statistics are preferred because of the 3D vectorial nature of the spatial error. Error vectors have three metric elements (one module and two angles) that were analyzed by spherical statistics. A study case has been presented and discussed in detail. Errors were calculating using 53 check points (CP) and CP coordinates were measured by a digitizer with submillimetre accuracy. The positional accuracy was analyzed by both the conventional method (modular errors analysis) and the proposed method (angular errors analysis) by 3D graphics and numerical spherical statistics. Two packages in R programming language were performed to obtain graphics automatically. The results indicated that the proposed method is advantageous as it offers a more complete analysis of the positional accuracy, such as angular error component, uniformity of the vector distribution, error isotropy, and error, in addition the modular error component by linear statistics.

  11. LIDAR AND INS FUSION IN PERIODS OF GPS OUTAGES FOR MOBILE LASER SCANNING MAPPING SYSTEMS

    Directory of Open Access Journals (Sweden)

    I. Klein

    2012-09-01

    Full Text Available Mobile laser scanning systems are becoming an increasingly popular means to obtain 3D coverage on a large scale. To perform the mapping, the exact position of the vehicle must be known throughout the trajectory. Exact position is achieved via integration of Global Positioning Systems (GPS and Inertial Navigation Systems (INS. Yet, in urban environments, cases of complete or even partial GPS outages may occur leaving the navigation solution to rely only on the INS. The INS navigation solution degrades with time as the Inertial Measurement Unit (IMU measurements contains noise, which permeates into the navigation equations. Degradation of the position determination leads to loss of data in such segments. To circumvent such drift and its effects, we propose fusing INS with lidar data by using building edges. This detection of edges is then translated into position data, which is used as an aiding to the INS. It thereby enables the determination of the vehicle position with a satisfactory level accuracy, sufficient to perform the laser-scanning based mapping in those outage periods.

  12. SU-E-J-72: Geant4 Simulations of Spot-Scanned Proton Beam Treatment Plans

    Energy Technology Data Exchange (ETDEWEB)

    Kanehira, T; Sutherland, K; Matsuura, T; Umegaki, K; Shirato, H [Hokkaido University, Sapporo, Hokkaido (Japan)

    2014-06-01

    Purpose: To evaluate density inhomogeneities which can effect dose distributions for real-time image gated spot-scanning proton therapy (RGPT), a dose calculation system, using treatment planning system VQA (Hitachi Ltd., Tokyo) spot position data, was developed based on Geant4. Methods: A Geant4 application was developed to simulate spot-scanned proton beams at Hokkaido University Hospital. A CT scan (0.98 × 0.98 × 1.25 mm) was performed for prostate cancer treatment with three or four inserted gold markers (diameter 1.5 mm, volume 1.77 mm3) in or near the target tumor. The CT data was read into VQA. A spot scanning plan was generated and exported to text files, specifying the beam energy and position of each spot. The text files were converted and read into our Geant4-based software. The spot position was converted into steering magnet field strength (in Tesla) for our beam nozzle. Individual protons were tracked from the vacuum chamber, through the helium chamber, steering magnets, dose monitors, etc., in a straight, horizontal line. The patient CT data was converted into materials with variable density and placed in a parametrized volume at the isocenter. Gold fiducial markers were represented in the CT data by two adjacent voxels (volume 2.38 mm3). 600,000 proton histories were tracked for each target spot. As one beam contained about 1,000 spots, approximately 600 million histories were recorded for each beam on a blade server. Two plans were considered: two beam horizontal opposed (90 and 270 degree) and three beam (0, 90 and 270 degree). Results: We are able to convert spot scanning plans from VQA and simulate them with our Geant4-based code. Our system can be used to evaluate the effect of dose reduction caused by gold markers used for RGPT. Conclusion: Our Geant4 application is able to calculate dose distributions for spot scanned proton therapy.

  13. Probabilistic scan mode of a robot manipulator workspace using EEG signals. Part I

    International Nuclear Information System (INIS)

    Auat Cheein, Fernando A; Di Sciascio, Fernando; Freire Bastos, Teodiano; Carelli, Ricardo

    2007-01-01

    In this paper a probabilistic-based workspace scan mode of a manipulator robot is presented. The scan mode is governed by a Brain Computer Interface (BCI) based on Event Related Potentials (Synchronization and Dessynchronization events). The user is capable to select a specific position at the robot's workspace, which should be reached by the manipulator. The robot workspace is divided into cells. Each cell has a probability value associated with it. Once the robot reaches a cell, its probability value is updated. The mode the scan is made is determined by the probability of all cells at the workspace. Finally, the manipulator is teleoperated via TCP/IP

  14. Indications of laparoscopic cholecystectomy based on preoperative imaging findings

    International Nuclear Information System (INIS)

    Wakizaka, Yoshitaka; Sano, Syuichi; Nakanishi, Yoshimi; Koike, Yoshinobu; Ozaki, Susumu; Iwanaga, Rikizo; Uchino, Junichi.

    1994-01-01

    We studied the indications for laparoscopic cholecystectomy (LC) and values of preoperative imaging findings in 82 patients who underwent preoperative imaging diagnostic tests (abdominal echogram, abdominal CAT scan, ERCP). We analyzed mainly patients who were considered to be indicated for LC but whose gallbladders could be removed by open laparotomy, or whose gallbladders were removed by open laparotomy but were considered indicated for LC from retrospective study. We found the following results. LC could be easily performed in patients with a history of severe acute cholecystitis if they had no findings of a thickened wall or negative gallbladder signs. Abdominal echogram and CAT scan were the best preoperative imaging tests for determining the gallbladder's state, especially for obstruction of the cystic duct. These results are important today when the operative indications of LC are extremely indefinite because of the accumulation of operative experience and technological improvements. (author)

  15. [Relationships between Myers-Briggs Type Indicator (MBTI) psychological type and marital satisfaction, divorce proneness, positive affect, and conflict regulation in clinic couples].

    Science.gov (United States)

    Kong, Seong Sook

    2010-06-01

    The purpose of the study was to investigate the relationships between the Myers-Briggs Type Indicator (MBTI) psychological type and marital satisfaction, divorce proneness, positive affect, and conflict regulation in couple visiting a clinic. Couples (n=62) who visited "M" couple clinic participated in the study. Data were collected from March to June 2009 using the Marital Satisfaction Scale, Marital Status Inventory, Positive Affect Inventory, and Conflict Regulation Inventory. The couples showed no significant differences in marital satisfaction, positive affect, and conflict regulation according to similarities between spouses in MBTI types. However, they showed significant differences in divorce proneness of husband according to a similarity in the Sensing/Intuition indicator. They also showed significant differences in divorce proneness, positive affect, and conflict regulation between the couples for ISTJ (Introversion, Sensing, Thinking, Judging) or ESTJ (Extraversion, Sensing, Thinking, Judging) types compared to other couples. When nurses counsel couples, they should understand that differences in psychological type between spouses affects their marital relationship. In addition, nurses should educate couples on the characteristics of each type according to the couple's types and help them to understand each other, especially for couples where one spouse is the ISTJ/ESTJ type. These interventions will improve marital satisfaction and prevent the divorce in these couples.

  16. Radiological site assessment at sun rose claim utilizing ScanPlot{sup SM} technology

    Energy Technology Data Exchange (ETDEWEB)

    Downey, H., E-mail: heath.downey@amecfw.com [Amec Foster Wheeler, Portland, ME (United States)

    2015-07-01

    ScanPlot{sup SM} gamma spectroscopy land survey system was utilized for the overland survey of uranium at the Sun Rose Claim in the Northwest Territories. The Sun Rose Claim is a former uranium exploration site and previous investigations had identified uranium ore and waste rock. ScanPlot{sup SM} radiological scan surveys were performed utilizing a backpack system. ScanPlot{sup SM} platform utilized spectroscopy grade sodium iodide detectors configured for optimal spatial coverage and radiation detection. Survey locations were recorded using an on-board global positioning system (GPS). The radiological spectral data from the radiation detectors is automatically logged and linked with the GPS coordinates to an on-board computer to create isocontour figures using a color scale to represent radioactivity levels. The advantage of utilizing the ScanPlot{sup SM} system for this assessment is that the nature and extent of uranium is provided without having to collect and assay a large number of samples. (author)

  17. High-speed scanning: an improved algorithm

    Science.gov (United States)

    Nachimuthu, A.; Hoang, Khoi

    1995-10-01

    In using machine vision for assessing an object's surface quality, many images are required to be processed in order to separate the good areas from the defective ones. Examples can be found in the leather hide grading process; in the inspection of garments/canvas on the production line; in the nesting of irregular shapes into a given surface... . The most common method of subtracting the total area from the sum of defective areas does not give an acceptable indication of how much of the `good' area can be used, particularly if the findings are to be used for the nesting of irregular shapes. This paper presents an image scanning technique which enables the estimation of useable areas within an inspected surface in terms of the user's definition, not the supplier's claims. That is, how much useable area the user can use, not the total good area as the supplier estimated. An important application of the developed technique is in the leather industry where the tanner (the supplier) and the footwear manufacturer (the user) are constantly locked in argument due to disputed quality standards of finished leather hide, which disrupts production schedules and wasted costs in re-grading, re- sorting... . The developed basic algorithm for area scanning of a digital image will be presented. The implementation of an improved scanning algorithm will be discussed in detail. The improved features include Boolean OR operations and many other innovative functions which aim at optimizing the scanning process in terms of computing time and the accurate estimation of useable areas.

  18. [Significance and mechanism of MSCT perfusion scan on differentiation of NSCLC].

    Science.gov (United States)

    Liu, Jin-Kang; Hu, Cheng-Ping; Zhou, Mo-Ling; Zhou, Hui; Xiong, Zeng; Xia, Yu; Chen, Wei

    2009-06-01

    To determine the significance of MSCT perfusion scan on differentiation of NSCLC and to investigate its possible mechanisms. Forty four NSCLC patients underwent CT perfusion scan by MSCT. Among them, 22 cases were selected to detected the two-dimensional tumor microvascular architecture phenotype (2D-TMAP), the relationships between CT perfusion parameters (BF, BV, PEI, TIP), and the differentiation of NSCLC were analysed by using the correlation analysis and trend test. Spearman correlation analysis was used to study the relationships between CT perfusion parameters, differentiation, and 2D-TMAP. The total BF, BV and PEI decreased with decreasing differentiation of NSCLC (P<0.05). The total PEI showed a positive correlation with the total MVD (P<0.05). There were negative correlations between the surrounding area BF, the total BF, BV, and PEI, the uncomplete lumen of the surrounding area MVD, and expression of PCNA, respectively (P<0.05). There were positive correlations between degree of differentiation and the uncomplete lumen of the surrounding area MVD (P<0.05). It was the same as degree of differentiation and expression of PCNA, VEGF, respectively. There were positive correlations between the uncomplete lumen of the surrounding area MVD and expression of VEGF, ephrinB2, EphB4, and PCNA, respectively (P<0.05). Perfusion parameters reflect the difference of density of vassels with mature functional lumen. Careful evaluation of the differences of blood flow pattern in pulmonary space-occupying lesions by MSCT perfusion scan can be used to identify the degree of NSCLC differentiation.

  19. Rapid-scan EPR imaging.

    Science.gov (United States)

    Eaton, Sandra S; Shi, Yilin; Woodcock, Lukas; Buchanan, Laura A; McPeak, Joseph; Quine, Richard W; Rinard, George A; Epel, Boris; Halpern, Howard J; Eaton, Gareth R

    2017-07-01

    In rapid-scan EPR the magnetic field or frequency is repeatedly scanned through the spectrum at rates that are much faster than in conventional continuous wave EPR. The signal is directly-detected with a mixer at the source frequency. Rapid-scan EPR is particularly advantageous when the scan rate through resonance is fast relative to electron spin relaxation rates. In such scans, there may be oscillations on the trailing edge of the spectrum. These oscillations can be removed by mathematical deconvolution to recover the slow-scan absorption spectrum. In cases of inhomogeneous broadening, the oscillations may interfere destructively to the extent that they are not visible. The deconvolution can be used even when it is not required, so spectra can be obtained in which some portions of the spectrum are in the rapid-scan regime and some are not. The technology developed for rapid-scan EPR can be applied generally so long as spectra are obtained in the linear response region. The detection of the full spectrum in each scan, the ability to use higher microwave power without saturation, and the noise filtering inherent in coherent averaging results in substantial improvement in signal-to-noise relative to conventional continuous wave spectroscopy, which is particularly advantageous for low-frequency EPR imaging. This overview describes the principles of rapid-scan EPR and the hardware used to generate the spectra. Examples are provided of its application to imaging of nitroxide radicals, diradicals, and spin-trapped radicals at a Larmor frequency of ca. 250MHz. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Reference nano-dimensional metrology by scanning transmission electron microscopy

    International Nuclear Information System (INIS)

    Dai, Gaoliang; Fluegge, Jens; Bosse, Harald; Heidelmann, Markus; Kübel, Christian; Prang, Robby

    2013-01-01

    Traceable and accurate reference dimensional metrology of nano-structures by scanning transmission electron microscopy (STEM) is introduced in the paper. Two methods, one based on the crystal lattice constant and the other based on the pitch of a feature pair, were applied to calibrate the TEM magnification. The threshold value, which was defined as the half-intensity of boundary materials, is suggested to extract the boundary position of features from the TEM image. Experimental investigations have demonstrated the high potential of the proposed methods. For instance, the standard deviation from ten repeated measurements of a line structure with a nominal 100 nm critical dimension (CD) reaches 1σ = 0.023 nm, about 0.02%. By intentionally introduced defocus and larger sample alignment errors, the investigation shows that these influences may reach 0.20 and 1.3 nm, respectively, indicating the importance of high-quality TEM measurements. Finally, a strategy for disseminating the destructive TEM results is introduced. Using this strategy, the CD of a reference material has been accurately determined. Its agreement over five independent TEM measurements is below 1.2 nm. (paper)

  1. A new method of CT scanning for the diagnosis of mandibular fractures

    International Nuclear Information System (INIS)

    Tsukagoshi, Taku; Satoh, Kaneshige; Onizuka, Takuya

    1990-01-01

    The condylar neck of the mandible is one of the most common fracture sites in the facial skeleton. Such a fracture is routinely diagnosed by A-P, lateral oblique, and Towne projection roentgenography or orthopantomography. Despite the combination of these films, fracture of the neck of the mandible is still difficult to diagnose definitely. Therefore, a new CT scanning method was developed for diagnosing fractures of the neck of the condylar mandible. The CT axis is projected along the length of the mandible, extending from the condyle to the symphysis. This projection visualizes both the condyle and the mandibular symphysis in the same plane. The patient is placed in a supine position with the head fully extended. The base line, a line extending from the midpoint of the glenoid fossa to the menton, is determined with a lateral facial cephalogram. CT scanning with a 5 mm window is performed in parallel with and 2 cm anterior to and 2 cm posterior to the base line. When CT scanning was performed in a healthy volunteer, the condition of the condyle and the condylar neck of the mandible was clearly shown, and the view extended from the condyle to the symphysis. For automobile accident patients in whom fracture of the neck of the mandible was associated with fracture of the symphysis, two fractures were found in the same plane. A newly developed CT scanning technique is useful in the diagnosis of fractures of the condylar neck of the mandible and in the identification of fractures at other mandibular sites. It also allows scanning of patients in a supine position, which may aid in managing patients with multiple traumas. (N.K.)

  2. Mass-positioning of Nanodiamonds Using Squeegee Technique

    OpenAIRE

    Cui, Ran; Shalaginov, Mikhail Y.; Shalaev, Vladimir M.

    2015-01-01

    Fluorescent color centers in diamond nanocrystals have recently become the focus of researchers because of their potential applications in quantum information processing, nano-sensing, biomarking, and bioimaging. One of the biggest challenges in working with nanodiamonds is how to position them precisely and efficiently to create strong interaction with nanoscale photonic structures. The most popular methods to position nanodiamonds are spin-coating and transporting via scanning probe microsc...

  3. Thallium 201 thyroid scan: differential diagnosis of benign and malignant nodules

    International Nuclear Information System (INIS)

    Oh, Jong Sub; Kim, Byong Geun; Park, Byung Ran; Kim, Se Jong; Ko, Kang Seok; Kim, Min Joong; Ji, Joo Yun

    1995-01-01

    To evaluate useful findings and diagnostic value of TI-201 thyroid scan in differentiating benign from malignant nodules. We studied 77 cold thyroid nodules proven histologically(27 malignant and 50 benign). Early (5-15 min) and delayed images(3-5 hours) were obtained after intravenous injection of thallium 201. In these nodules, we retrospectively analyzed the degree of TI-201 uptake in early and delayed images, histopathologic type, size, and presence or absence of cystic change in the sonograms of 22 malignant nodules. Useful finding for diagnosis of malignant nodules was strong uptake of TI-201 in early and delayed images(specificity: 98%, sensitivity: 63%, positive predictive value: 94.4%). Useful finding for benign nodules was no uptake of TI-201 in delayed image(specificity: 88.9%, sensitivity: 68%, positive predictive value: 91.9%). The accuracy of TI-201 thyroid scan in differentiating benign from malignant nodules was 66.2%. The nodules with strong TI-201 uptake in early image and low TI-201 uptake in delayed image were malignant in 29.4%. Cystic changes were found in 40% of malignant nodules with atypical TI-201 uptake. TI-201 thyroid scan showed high specificity in follicular neoplasm and adenomatous goiter in which differentiation of benignancy and malignancy is difficult with only cytologic examination. We consider that TI-201 thyroid scan is valuable in differentiating benign from malignant nodules and when combined with fine needle aspiration and ultrasound examination, it will enable more accurate differential diagnosis between benign and malignant thyroid nodules

  4. Positive enteric contrast material for abdominal and pelvic CT with automatic exposure control: What is the effect on patient radiation exposure?

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhen J., E-mail: jane.wang@radiology.ucsf.edu [Department of Radiology, University of California San Francisco, 505 Parnassus Avenue, San Francisco, CA 94143-0628 (United States); Chen, Katherine S.; Gould, Robert; Coakley, Fergus V.; Fu Yanjun; Yeh, Benjamin M. [Department of Radiology, University of California San Francisco, 505 Parnassus Avenue, San Francisco, CA 94143-0628 (United States)

    2011-08-15

    Objective: To assess the effect of positive enteric contrast administration on automatic exposure control (AEC) CT radiation exposure in (1) a CT phantom, and (2) a retrospective review of patients. Materials and methods: We scanned a CT phantom containing simulated bowel that was sequentially filled with water and positive enteric contrast, and recorded the mean volume CT dose index (CTDIvol). We also identified 17 patients who had undergone 2 technically comparable CT scans of the abdomen and pelvis, one with positive enteric contrast and the other with oral water. Paired Student's t-tests were used to compare the mean CTDIvol between scans performed with and without positive enteric contrast. Both the phantom and patient CT scans were performed using AEC with a fixed noise index. Results: The mean CTDIvol for the phantom with simulated bowel containing water and positive enteric contrast were 8.2 {+-} 0.2 mGy, and 8.7 {+-} 0.1 mGy (6.1% higher than water, p = 0.02), respectively. The mean CTDIvol for patients scanned with oral water and with positive enteric contrast were 11.8 mGy and 13.1 mGy, respectively (p = 0.003). This corresponded to a mean CTDIvol which was 11.0% higher (range: 0.0-20.7% higher) in scans with positive enteric contrast than those with oral water in patients. Conclusions: When automatic exposure control is utilized for abdominopelvic CT, the radiation exposure, as measured by CTDIvol, is higher for scans performed with positive enteric contrast than those with oral water.

  5. Is there a role of whole-body bone scan in patients with esophageal squamous cell carcinoma

    Science.gov (United States)

    2012-01-01

    Background Correct detection of bone metastases in patients with esophageal squamous cell carcinoma is pivotal for prognosis and selection of an appropriate treatment regimen. Whole-body bone scan for staging is not routinely recommended in patients with esophageal squamous cell carcinoma. The aim of this study was to investigate the role of bone scan in detecting bone metastases in patients with esophageal squamous cell carcinoma. Methods We retrospectively evaluated the radiographic and scintigraphic images of 360 esophageal squamous cell carcinoma patients between 1999 and 2008. Of these 360 patients, 288 patients received bone scan during pretreatment staging, and sensitivity, specificity, positive predictive value, and negative predictive value of bone scan were determined. Of these 360 patients, surgery was performed in 161 patients including 119 patients with preoperative bone scan and 42 patients without preoperative bone scan. Among these 161 patients receiving surgery, 133 patients had stages II + III disease, including 99 patients with preoperative bone scan and 34 patients without preoperative bone scan. Bone recurrence-free survival and overall survival were compared in all 161 patients and 133 stages II + III patients, respectively. Results The diagnostic performance for bone metastasis was as follows: sensitivity, 80%; specificity, 90.1%; positive predictive value, 43.5%; and negative predictive value, 97.9%. In all 161 patients receiving surgery, absence of preoperative bone scan was significantly associated with inferior bone recurrence-free survival (P = 0.009, univariately). In multivariate comparison, absence of preoperative bone scan (P = 0.012, odds ratio: 5.053) represented the independent adverse prognosticator for bone recurrence-free survival. In 133 stages II + III patients receiving surgery, absence of preoperative bone scan was significantly associated with inferior bone recurrence-free survival (P = 0

  6. Is there a role of whole-body bone scan in patients with esophageal squamous cell carcinoma

    International Nuclear Information System (INIS)

    Li, Shau-Hsuan; Huang, Yung-Cheng; Huang, Wan-Ting; Lin, Wei-Che; Liu, Chien-Ting; Tien, Wan-Yu; Lu, Hung-I

    2012-01-01

    Correct detection of bone metastases in patients with esophageal squamous cell carcinoma is pivotal for prognosis and selection of an appropriate treatment regimen. Whole-body bone scan for staging is not routinely recommended in patients with esophageal squamous cell carcinoma. The aim of this study was to investigate the role of bone scan in detecting bone metastases in patients with esophageal squamous cell carcinoma. We retrospectively evaluated the radiographic and scintigraphic images of 360 esophageal squamous cell carcinoma patients between 1999 and 2008. Of these 360 patients, 288 patients received bone scan during pretreatment staging, and sensitivity, specificity, positive predictive value, and negative predictive value of bone scan were determined. Of these 360 patients, surgery was performed in 161 patients including 119 patients with preoperative bone scan and 42 patients without preoperative bone scan. Among these 161 patients receiving surgery, 133 patients had stages II + III disease, including 99 patients with preoperative bone scan and 34 patients without preoperative bone scan. Bone recurrence-free survival and overall survival were compared in all 161 patients and 133 stages II + III patients, respectively. The diagnostic performance for bone metastasis was as follows: sensitivity, 80%; specificity, 90.1%; positive predictive value, 43.5%; and negative predictive value, 97.9%. In all 161 patients receiving surgery, absence of preoperative bone scan was significantly associated with inferior bone recurrence-free survival (P = 0.009, univariately). In multivariate comparison, absence of preoperative bone scan (P = 0.012, odds ratio: 5.053) represented the independent adverse prognosticator for bone recurrence-free survival. In 133 stages II + III patients receiving surgery, absence of preoperative bone scan was significantly associated with inferior bone recurrence-free survival (P = 0.003, univariately) and overall survival (P = 0

  7. Relative value of thallium-201 and iodine-131 scans in the detection of recurrence or distant metastasis of well differentiated thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Lin Jen-Der; Weng Hsiao-Fen; Lu Wen-Tsoung [Division of Endocrinology and Metabolism, Chang Gung Memorial Hospital (Taiwan, Province of China); Kao Pan-Fu; Huang Miau-Ju [Department of Nuclear Medicine, Chang Gung Memorial Hospital, Taiwan (Taiwan, Province of China)

    1998-07-01

    Radioactive iodine ({sup 131}I) has been found to be more sensitive and more specific than thallium-201 for the detection of distant metastases and thyroid remnants in the neck in cases of well-differentiated thyroid carcinoma. {sup 201}Tl has been deemed particularly useful in localizing metastases or recurrence in patients with a negative {sup 131}I scan and abnormal levels of serum thyroglobulin (Tg). This study aimed to: (1) determine the value of {sup 201}Tl imaging in localizing metastases or recurrence in patients with well-differentiated thyroid carcinoma, and (2) evaluate the false-positive and false-negative results of {sup 131}I and {sup 201}Tl scintigraphy. Sixty-two thyroid remnant ablated patients who underwent simultaneous postoperative {sup 201}Tl and {sup 131}I scans and and serum Tg determinations were evaluated. Fifty patients had papillary thyroid carcinomas and 12 had follicular thyroid carcinomas. {sup 201}Tl imaging was performed before the {sup 131}I studies. Of the 62 patients who underwent {sup 201}Tl imaging studies, 24 were found to have positive results, with local recurrence or distant metastases. Patients with positive results in the {sup 201}Tl imaging studies tended to be older, were mor often male, had higher Tg levels and had a higher recurrence rate. Of these 24 patients, ten had negative diagnostic or therapeutic {sup 131}I scans. Concurrently, serum Tg levels were less than 5 ng/ml in five of these ten patients. Three patients were deemed false positive by {sup 201}Tl scans; one had a parotid tumour, one a periodontal abscess and one lung metastasis. Among the 38 patients with negative {sup 201}Tl scans, 11 had positive findings on {sup 131}I scans. Three had distant metastases: two with lung metastases and one with bone metastases. Patients with false-positive results on {sup 131}I scans included those with biliary tract stones, ovarian cysts, and breast secretion. Of the 27 patients with negative {sup 201}Tl and {sup 131}I

  8. Incidental Visualization of Thyroid Gland on Bone Scan Caused by Graves' Hyperthyroidism

    International Nuclear Information System (INIS)

    Sohn, Myung Hee; Jeong, Hwan Jeong; Kim, Dong Wook; Lim, Seok Tae

    2009-01-01

    A 45-year-old man presented with fatigue and weight loss underwent a Tc-99m MDP bone scan because of increased serum alkaline phosphatase. Delayed images at 4 hours demonstrated diffuse increased activity throughout both lobes of the thyroid in the absence of activity of the stomach and salivary glands. Thyroid laboratory indices and a Tc-99m pertechnetate thyroid scan suggested Graves' hyperthyroidism

  9. Radiopharmaceutical scanning agents

    International Nuclear Information System (INIS)

    1976-01-01

    This invention is directed to dispersions useful in preparing radiopharmaceutical scanning agents, to technetium labelled dispersions, to methods for preparing such dispersions and to their use as scanning agents

  10. Innovation indices: the need for positioning them where they properly belong.

    Science.gov (United States)

    Kozłowski, Jan

    A specific quality of the discussion about innovation indices (scoreboards) is that more often than not the subject is dealt with from a purely technical point of view. Such a narrow approach silently assumes that indices used as a policy tool are an accurate reflection of the phenomenon and should not be questioned, and also that the whole discussion concerning them should refer to methodological aspects and is best left to the statisticians. This author is of the opinion that for an accurate evaluation of the value of indices as a policy tool, it is necessary to consider the matter from the broader point of view and from the context in which such indices are generated and used. This article puts forward the thesis that progress in science and innovation policy studies depends on a diversity of issues, approaches and perspectives. If that is the case, maintaining thematic and methodological variety may be more important than creating coherent and closed analytical tools, i.e. indices. The advantage of indices is that they focus attention on those variables which are deemed to be key. Among their disadvantages, however, are their highly abstract nature (in order to understand innovation-related phenomena, it is necessary to study them in tangible, composite forms); their tendency to skip unmeasurable determinants; their prior acceptance of definitions and concepts of innovation (instead of searching for them); the way they apply a single yardstick to diverse countries and regions, assumed linearity and causality in a complex and non-linear world, the way they direct policy towards implementing indicators (rather than identifying and solving problems). It is suggested that big data revolution will allow the emergence of a new measurement tools that will replace innovation indices.

  11. The clinical impact of PET scanning in patients with melanoma: A prospective study

    International Nuclear Information System (INIS)

    Kalff, V.; Hicks, R.J.; Binns, D.S.; Henderson, M.A.; Ainslie, J.; Jenner, D.A.

    1998-01-01

    Full text: Small series have shown that PET scanning using F-18 fluorodeoxyglucose (FDG), can quite accurately stage patients melanoma. At this Institute these patients are only sent for PET imaging if they have high risk melanomas ( >3 Clarke's grade primaries) or there remains any significant doubt as to their clinical staging or management after the completion of conventional screening. This prospective study examines how PET scan findings influenced the clinical management decisions in 53 patients (29 males, mean age 54±13 yrs: range 31-81 yrs) Referring doctors were asked to indicate reason for the PET scan, stage their patients on the basis of all their current investigations, and to indicate their management plans prior to PET scanning. Follow-up of subsequent patient management at 2-4 weeks post PET scan was then obtained and compared to pre PET plans. PET was used to stage 26 patients, restage 17, follow-up 5, assess recurrence in 3, and other in 2 patients. To date follow-up has shown that in 32/49 (65%) patients PET was used to triage patients to locoregional surgery (10 patients), radical radiotherapy (5 patients), or to continuing follow-up only (17 patients). Three further high risk patients with negative PET scans had sentinel mode biopsy. In only 13 patients was management already determined, with planned treatment being changed in 6. Four patients have not had their post PET scan review yet. To date proven false negative PET scans have occurred in 3 cases, 2 sentinel node biopsies showed microscopic disease, and one scan incorrectly labelled gall-bladder melanoma as hydro-nephrotic kidney. Interestingly in 3 cases, PET discovered other unsuspected tumours (rectum x 2, plasmacytoma). PET scanning has been incorporated into routine management to triage most high risk patients, but it still alters interventions in half of those patients where management has already been planned. PET clearly misses small volume disease, the importance of which is

  12. Construction of a four tip scanning tunneling microscope/scanning electron microscope combination and conductivity measurements of silicide nanowires; Aufbau einer Vierspitzen-Rastertunnelmikroskop/Rasterelektronenmikroskop-Kombination und Leitfaehigkeitsmessungen an Silizid Nanodraehten

    Energy Technology Data Exchange (ETDEWEB)

    Zubkov, Evgeniy

    2013-09-01

    In this work the combination of a four-tip scanning tunneling microscope with a scanning electron microscope is presented. By means of this apparatus it is possible to perform the conductivity measurements on the in-situ prepared nanostructures in ultra-high vacuum. With the aid of a scanning electron microscope (SEM), it becomes possible to position the tunneling tips of the four-tip scanning tunneling microscope (STM), so that an arrangement for a four-point probe measurement on nanostructures can be obtained. The STM head was built according to the novel coaxial Beetle concept. This concept allows on the one hand, a very compact arrangement of the components of the STM and on the other hand, the new-built STM head has a good mechanical stability, in order to achieve atomic resolution with all four STM units. The atomic resolution of the STM units was confirmed by scanning a Si(111)-7 x 7 surface. The thermal drift during the STM operation, as well as the resonant frequencies of the mechanical structure of the STM head, were determined. The scanning electron microscope allows the precise and safe navigation of the tunneling tips on the sample surface. Multi tip spectroscopy with up to four STM units can be performed synchronously. To demonstrate the capabilities of the new-built apparatus the conductivity measurements were carried out on metallic yttrium silicide nanowires. The nanowires were prepared by the in-situ deposition of yttrium on a heated Si(110) sample surface. Current-voltage curves were recorded on the nanowires and on the wetting layer in-between. The curves indicate an existence of the Schottky barrier between the yttrium silicide nanowires and the silicon bulk. By means of the two-tip measurements with a gate, the insulating property of the Schottky barrier has been confirmed. Using this Schottky barrier, it is possible to limit the current to the nanowire and to prevent it from flowing through the silicon bulk. A four-tip resistance measurement

  13. Multi-hop localization algorithm based on grid-scanning for wireless sensor networks.

    Science.gov (United States)

    Wan, Jiangwen; Guo, Xiaolei; Yu, Ning; Wu, Yinfeng; Feng, Renjian

    2011-01-01

    For large-scale wireless sensor networks (WSNs) with a minority of anchor nodes, multi-hop localization is a popular scheme for determining the geographical positions of the normal nodes. However, in practice existing multi-hop localization methods suffer from various kinds of problems, such as poor adaptability to irregular topology, high computational complexity, low positioning accuracy, etc. To address these issues in this paper, we propose a novel Multi-hop Localization algorithm based on Grid-Scanning (MLGS). First, the factors that influence the multi-hop distance estimation are studied and a more realistic multi-hop localization model is constructed. Then, the feasible regions of the normal nodes are determined according to the intersection of bounding square rings. Finally, a verifiably good approximation scheme based on grid-scanning is developed to estimate the coordinates of the normal nodes. Additionally, the positioning accuracy of the normal nodes can be improved through neighbors' collaboration. Extensive simulations are performed in isotropic and anisotropic networks. The comparisons with some typical algorithms of node localization confirm the effectiveness and efficiency of our algorithm.

  14. Nuclear Heart Scan

    Science.gov (United States)

    ... Home / Nuclear Heart Scan Nuclear Heart Scan Also known as Nuclear Stress Test , ... Learn More Connect With Us Contact Us Directly Policies Privacy Policy Freedom of Information Act (FOIA) Accessibility ...

  15. Fast IMRT with narrow high energy scanned photon beams

    Energy Technology Data Exchange (ETDEWEB)

    Andreassen, Bjoern; Straaring t, Sara Janek; Holmberg, Rickard; Naefstadius, Peder; Brahme, Anders [Department of Medical Radiation Physics, Karolinska Institutet and Stockholm University, P.O. Box 260, SE-171 76 Stockholm (Sweden); Department of Hospital Physics, Karolinska University Hospital, SE-171 76 Stockholm (Sweden); Department of Medical Radiation Physics, Karolinska Institutet and Stockholm University, P.O. Box 260, SE-171 76 Stockholm, Sweden and Department of Hospital Physics, Karolinska University Hospital, SE-171 76 Stockholm (Sweden)

    2011-08-15

    Purpose: Since the first publications on intensity modulated radiation therapy (IMRT) in the early 1980s almost all efforts have been focused on fairly time consuming dynamic or segmental multileaf collimation. With narrow fast scanned photon beams, the flexibility and accuracy in beam shaping increases, not least in combination with fast penumbra trimming multileaf collimators. Previously, experiments have been performed with full range targets, generating a broad bremsstrahlung beam, in combination with multileaf collimators or material compensators. In the present publication, the first measurements with fast narrow high energy (50 MV) scanned photon beams are presented indicating an interesting performance increase even though some of the hardware used were suboptimal. Methods: Inverse therapy planning was used to calculate optimal scanning patterns to generate dose distributions with interesting properties for fast IMRT. To fully utilize the dose distributional advantages with scanned beams, it is necessary to use narrow high energy beams from a thin bremsstrahlung target and a powerful purging magnet capable of deflecting the transmitted electron beam away from the generated photons onto a dedicated electron collector. During the present measurements the scanning system, purging magnet, and electron collimator in the treatment head of the MM50 racetrack accelerator was used with 3-6 mm thick bremsstrahlung targets of beryllium. The dose distributions were measured with diodes in water and with EDR2 film in PMMA. Monte Carlo simulations with geant4 were used to study the influence of the electrons transmitted through the target on the photon pencil beam kernel. Results: The full width at half-maximum (FWHM) of the scanned photon beam was 34 mm measured at isocenter, below 9.5 cm of water, 1 m from the 3 mm Be bremsstrahlung target. To generate a homogeneous dose distribution in a 10 x 10 cm{sup 2} field, the authors used a spot matrix of 100 equal intensity

  16. Atmospheric scanning electron microscope for correlative microscopy.

    Science.gov (United States)

    Morrison, Ian E G; Dennison, Clare L; Nishiyama, Hidetoshi; Suga, Mitsuo; Sato, Chikara; Yarwood, Andrew; O'Toole, Peter J

    2012-01-01

    The JEOL ClairScope is the first truly correlative scanning electron and optical microscope. An inverted scanning electron microscope (SEM) column allows electron images of wet samples to be obtained in ambient conditions in a biological culture dish, via a silicon nitride film window in the base. A standard inverted optical microscope positioned above the dish holder can be used to take reflected light and epifluorescence images of the same sample, under atmospheric conditions that permit biochemical modifications. For SEM, the open dish allows successive staining operations to be performed without moving the holder. The standard optical color camera used for fluorescence imaging can be exchanged for a high-sensitivity monochrome camera to detect low-intensity fluorescence signals, and also cathodoluminescence emission from nanophosphor particles. If these particles are applied to the sample at a suitable density, they can greatly assist the task of perfecting the correlation between the optical and electron images. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Scanning Electron Microscope Calibration Using a Multi-Image Non-Linear Minimization Process

    Science.gov (United States)

    Cui, Le; Marchand, Éric

    2015-04-01

    A scanning electron micros