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Sample records for enhanced ct impact

  1. The impact of the PET/CT in comparison with the same day contrast enhanced CT in breast cancer management

    International Nuclear Information System (INIS)

    Piperkova, E.; Raphael, B.; Altinyay, M.; Castellon, I.; Libes, R.; Abdel-Dayem, H.

    2006-01-01

    Full text: The aim of this study is to evaluate the impact of 18F-fluorodeoxyglucose FDG positron emission tomography with fused computerized tomography (PET/CT) in comparison with the same day contrast enhanced CT (CE-CT) in the breast cancer (BC) management. 68 studies in 48 BC patients, 8 for initial and 60 for restaging disease, after surgery, radiation/chemotherapy, for radiation therapy planning or evaluating treatment response were included. All patients underwent whole body PET/CT for diagnostic purposes followed by CE-CT diagnostic scans of selected body regions. PET/CT was performed approximately 90 minutes following 10-15 mCi of 18F-FDG on a GE Discovery PET/CT system. CT part acquired with low dose X-ray for localization and attenuation correction. The CE-CT was performed according to departmental protocol. Out of a total of 235 lesions in 68 PET/CT and CE-CT studies, 189 were concordant between PET/CT and CE-CT. However, there were 46 discordant lesions, which were verified by either follow-up or biopsy. PET/CT correctly identified 25 (True Positive-TP). CE-CT identified 2 TP lesions missed by PET/CT (False negative): one liver metastasis with necrosis, which is a known non-avid FDG, the other was a missed abdominal metastatic node, which did not change staging or treatment. PET/CT incorrectly identified 2 lesions (False Positive) while CE-CT incorrectly identified 17 FP. For evaluating treatment response in 40 follow up studies PET/CT reported complete response in 15, partial response in 11, stable disease in 2, progression in 5, and free of disease following surgery - in 7. The CE-CT described progression of the disease in 1 PET/CT true negative study and no progression in 2 TP PET/CT studies. In this study, PET/CT played more important role than CECT scans alone and provided an impact on the management of BC patients

  2. Solitary pulmonary nodules: Impact of quantitative contrast-enhanced CT on the cost-effectiveness of FDG-PET

    International Nuclear Information System (INIS)

    Comber, L.A.; Keith, C.J.; Griffiths, M.; Miles, K.A.

    2003-01-01

    AIM: To determine the impact of quantitative contrast-enhanced computed tomography (QECT) on the cost-effectiveness of diagnostic strategies for the assessment of solitary pulmonary nodules (SPNs). MATERIALS AND METHODS: Four diagnostic strategies were evaluated using decision tree analysis: conventional CT alone; conventional CT followed by QECT; conventional CT followed positron emission tomography (PET); and conventional CT followed by QECT and PET (QECT+PET). The average cost per patient, accuracy of management and incremental cost:accuracy ratio (ICAR) were determined for each strategy. Although baseline assumptions reflected the Australian setting, sensitivity analysis was used to extrapolate the results to the UK. RESULTS: At the baseline prevalence of malignancy (54%) and cost of PET relative to surgery (16%), the QECT strategy incurs the least cost ($5560/patient) but the QECT+PET strategy is the most cost-effective (ICAR $12059/patient). At reported levels of disease prevalence (68.5%) and cost of PET relative to surgery (29.9%) in the UK, the QECT strategy is the most cost-effective. CONCLUSION: QECT offers a cost-effective approach to evaluation of SPNs. Whether QECT is used alone or in combination with PET will depend upon local availability and regional values for prior probability of malignancy within SPNs and the cost of PET relative to surgery

  3. Contrast enhancement CT by iopamidol

    International Nuclear Information System (INIS)

    Mori, Masaki; Makita, Nobue; Yanai, Kyoko

    1984-01-01

    In order to evaluate the contrast enhancement effect and safety of iopamidol (IOP) in CT examination, IOP was compared with angiographin (AG). In the liver and abdominal aorta, peak CT values were obtained earlier and were higher in the group with AG than in the group with IOP. However, CT values in the group with IOP decreased a little more slowly than those in the group with AG. There was no significant difference in the effect on contrast enhancement between the groups. Intravenous injection of IOP caused lower degree of burning sensation than that of AG, and some of the patients with IOP did not feel burning sensation at all. Changes in clinical laboratory values were slight before and after intravenous injection of IOP. These results suggest that IOP is satisfactory in terms of safety and effect on contrast enhancement in CT examination. (Namekawa, K.)

  4. Contrast enhanced CT of spinal cord angioma

    International Nuclear Information System (INIS)

    Nakamura, Takahiko; Ebitani, Tsutomu; Honma, Takao; Sofue, Muroto; Nakamura, Shigeru

    1982-01-01

    Contrast enhanced CT on 6 patients with spinal cord angioma showed enhancement in 2 of them. The conditions to produce contrast enhancement were the window width of 100 - 200, and the window level of 0 - 50. In spinal cord angioma, contrast enhanced CT is presently only an adjunct to angiography and myelography. Nevertheless, contrast enhanced CT is useful in the screening test for spinal cord angioma, in the patients who are nonindicated to angiography, and in the postoperative follow-up. (Ueda, J.)

  5. Impact of the use of contrast-enhancement multidetector CT for acute appendicitis: a prospective comparison with the Alvarado score

    International Nuclear Information System (INIS)

    Choi, Mi Young; Yoon, Seong Eon; Lee, Young Hwan; Choi, Shi Sung; Park, Seong Hoon; Juhng, Seong Kwan; Yoon, Kwon Ha; Park, Seong Ho

    2007-01-01

    To determine the diagnostic performance of contrast-enhanced multidetector CT (MDCT) and the Alvarado score for acute appendicitis. MDCT and determination of the Alvarado score were prospectively performed in 282 patients with 146 pathologically proven cases of acute appendicitis and 136 pathologically proven or clinically diagnosed cases of non-acute appendicitis. To compare the diagnostic performance of MDCT and the Alvarado score, the patients were subdivided according to age and sex, and receiver operating characteristics (ROC) analysis and Spearman rank correlation were performed. ROC analysis revealed that the optimal cut off value of the CT appendicitis grades was 2 in all patients, resulting in a sensitivity of 96.6% and a specificity of 94.9%. The optimal cut off values of the Alvarado score was different according to age and sex, resulting in a sensitivity of 85.6% and a specificity of 48.5%. There was a significant correlation between the CT appendicitis grades and the surgical-pathological grades (r = 0.496, ρ < .0001). However, no significant correlation was observed between the Alvarado score and the surgical-pathological grades. Contrast-enhanced MDCT has a higher diagnostic accuracy and significant correlation with pathological findings than those of the Alvarado score in patients with acute appendicitis

  6. Impact of the use of contrast-enhancement multidetector CT for acute appendicitis: a prospective comparison with the Alvarado score

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    Choi, Mi Young; Yoon, Seong Eon; Lee, Young Hwan; Choi, Shi Sung; Park, Seong Hoon; Juhng, Seong Kwan; Yoon, Kwon Ha [Wonkwang University School of Medicine, Iksan (Korea, Republic of); Park, Seong Ho [University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2007-12-15

    To determine the diagnostic performance of contrast-enhanced multidetector CT (MDCT) and the Alvarado score for acute appendicitis. MDCT and determination of the Alvarado score were prospectively performed in 282 patients with 146 pathologically proven cases of acute appendicitis and 136 pathologically proven or clinically diagnosed cases of non-acute appendicitis. To compare the diagnostic performance of MDCT and the Alvarado score, the patients were subdivided according to age and sex, and receiver operating characteristics (ROC) analysis and Spearman rank correlation were performed. ROC analysis revealed that the optimal cut off value of the CT appendicitis grades was 2 in all patients, resulting in a sensitivity of 96.6% and a specificity of 94.9%. The optimal cut off values of the Alvarado score was different according to age and sex, resulting in a sensitivity of 85.6% and a specificity of 48.5%. There was a significant correlation between the CT appendicitis grades and the surgical-pathological grades (r = 0.496, {rho} < .0001). However, no significant correlation was observed between the Alvarado score and the surgical-pathological grades. Contrast-enhanced MDCT has a higher diagnostic accuracy and significant correlation with pathological findings than those of the Alvarado score in patients with acute appendicitis.

  7. CT findings of pancreatic carcinoma. Evaluation with the combined method of early enhancement CT and high dose enhancement CT

    International Nuclear Information System (INIS)

    Itoh, Shigeki; Endo, Tokiko; Isomura, Takayuki; Ishigaki, Takeo; Ikeda, Mitsuru; Senda, Kouhei.

    1995-01-01

    Computed tomographic (CT) findings of pancreatic ductal adenocarcinoma were studied with the combined method of early enhancement CT and high dose enhancement CT in 72 carcinomas. Common Findings were change in pancreatic contour, abnormal attenuation in a tumor and dilatation of the main pancreatic duct. The incidence of abnormal attenuation and dilatation of the main pancreatic duct and bile duct was constant regardless of tumor size. The finding of hypoattenuation at early enhancement CT was most useful for demonstrating a carcinoma. However, this finding was negative in ten cases, five of which showed inhomogenous hyperattenuation at high dose enhancement CT. The detection of change in pancreatic contour and dilatation of the main pancreatic duct was most frequent at high dose enhancement CT. The finding of change in pancreatic contour and/or abnormal attenuation in a tumor could be detected in 47 cases at plain CT, 66 at early enhancement CT and 65 at high dose enhancement CT. Since the four cases in which neither finding was detected by any CT method showed dilatated main pancreatic duct, there was no case without abnormal CT findings. This combined CT method will be a reliable diagnostic technique in the imaging of pancreatic carcinoma. (author)

  8. Evaluation of living liver donors using contrast enhanced multidetector CT – The radiologists impact on donor selection

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    Ringe Kristina

    2012-07-01

    Full Text Available Abstract Background Living donor liver transplantation (LDLT is a valuable and legitimate treatment for patients with end-stage liver disease. Computed tomography (CT has proven to be an important tool in the process of donor evaluation. The purpose of this study was to evaluate the significance of CT in the donor selection process. Methods Between May 1999 and October 2010 170 candidate donors underwent biphasic CT. We retrospectively reviewed the results of the CT and liver volumetry, and assessed reasons for rejection. Results 89 candidates underwent partial liver resection (52.4%. Based on the results of liver CT and volumetry 22 candidates were excluded as donors (31% of the cases. Reasons included fatty liver (n = 9, vascular anatomical variants (n = 4, incidental finding of hemangioma and focal nodular hyperplasia (n = 1 and small (n = 5 or large for size (n = 5 graft volume. Conclusion CT based imaging of the liver in combination with dedicated software plays a key role in the process of evaluation of candidates for LDLT. It may account for up to 1/3 of the contraindications for LDLT.

  9. Evaluation of living liver donors using contrast enhanced multidetector CT – The radiologists impact on donor selection

    International Nuclear Information System (INIS)

    Ringe, Kristina Imeen; Ringe, Bastian Paul; Falck, Christian von; Shin, Hoen-oh; Becker, Thomas; Pfister, Eva-Doreen; Wacker, Frank; Ringe, Burckhardt

    2012-01-01

    Living donor liver transplantation (LDLT) is a valuable and legitimate treatment for patients with end-stage liver disease. Computed tomography (CT) has proven to be an important tool in the process of donor evaluation. The purpose of this study was to evaluate the significance of CT in the donor selection process. Between May 1999 and October 2010 170 candidate donors underwent biphasic CT. We retrospectively reviewed the results of the CT and liver volumetry, and assessed reasons for rejection. 89 candidates underwent partial liver resection (52.4%). Based on the results of liver CT and volumetry 22 candidates were excluded as donors (31% of the cases). Reasons included fatty liver (n = 9), vascular anatomical variants (n = 4), incidental finding of hemangioma and focal nodular hyperplasia (n = 1) and small (n = 5) or large for size (n = 5) graft volume. CT based imaging of the liver in combination with dedicated software plays a key role in the process of evaluation of candidates for LDLT. It may account for up to 1/3 of the contraindications for LDLT

  10. Patterns of uterine enhancement with helical CT

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    Kaur, H.; Loyer, E.M.; Charnsangavej, C. [Department of Diagnostic Radiology, Box 57, The University of Texas, M.D. Anderson Cancer Center, 1515 Holcombe Blvd. Houston, TX 77030 (United States); Minami, M. [Department of Radiology, Faculty of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113 (Japan)

    1998-10-01

    Objective: The purpose of this study was to evaluate the enhancement characteristics of the normal uterine body and cervix using dynamic contrast-enhanced helical CT. Methods: Thirty-eight women scheduled for pelvic CT for non-gynecologic malignancies underwent dynamic contrast-enhanced helical CT of the pelvis. Data acquisition was during the arterial phase (30-45 s after the start of injection), the parenchymal phase (90-120 s after the start of injection), and delayed phase (3-9 min after the start of injection). The images were evaluated by four radiologists for the pattern of myometrial and cervical enhancement. Correlation was made with the age and menstrual status of the patients. Results: In the uterine body, three types of enhancement were observed. Type 1 enhancement, seen in 16 patients (42%), was characterized by the visualization of a subendometrial zone of enhancement, 30-120 s after the start of injection. Eight of these patients also showed an enhancing zone in the outer myometrium. Both zones were transitory, and in all cases, the uterus became homogeneous in the delayed phase. This pattern was seen predominantly in premenopausal women with a mean age of 34 years. Type 2 enhancement, seen in 17 cases (45%), was defined by the absence of subendometrial enhancement in the early phase. Enhancement was either diffuse from the outset or originated in the outer myometrium. This pattern was seen nearly equally in premenopausal and postmenopausal women with a mean age of 40 years. Type 3 enhancement was seen in five postmenopausal patients (13%) with a mean age of 53 years and was characterized by faint diffuse enhancement. In the cervix, a zonal pattern of enhancement defining inner and outer stroma was seen in 23 patients (61%). Fifteen patients were premenopausal and eight were postmenopausal. Conclusion: In this study, we have shown a transitory zonal distribution of the contrast in the myometrium and cervix using dynamic contrast-enhanced helical CT

  11. Patterns of uterine enhancement with helical CT

    International Nuclear Information System (INIS)

    Kaur, H.; Loyer, E.M.; Charnsangavej, C.; Minami, M.

    1998-01-01

    Objective: The purpose of this study was to evaluate the enhancement characteristics of the normal uterine body and cervix using dynamic contrast-enhanced helical CT. Methods: Thirty-eight women scheduled for pelvic CT for non-gynecologic malignancies underwent dynamic contrast-enhanced helical CT of the pelvis. Data acquisition was during the arterial phase (30-45 s after the start of injection), the parenchymal phase (90-120 s after the start of injection), and delayed phase (3-9 min after the start of injection). The images were evaluated by four radiologists for the pattern of myometrial and cervical enhancement. Correlation was made with the age and menstrual status of the patients. Results: In the uterine body, three types of enhancement were observed. Type 1 enhancement, seen in 16 patients (42%), was characterized by the visualization of a subendometrial zone of enhancement, 30-120 s after the start of injection. Eight of these patients also showed an enhancing zone in the outer myometrium. Both zones were transitory, and in all cases, the uterus became homogeneous in the delayed phase. This pattern was seen predominantly in premenopausal women with a mean age of 34 years. Type 2 enhancement, seen in 17 cases (45%), was defined by the absence of subendometrial enhancement in the early phase. Enhancement was either diffuse from the outset or originated in the outer myometrium. This pattern was seen nearly equally in premenopausal and postmenopausal women with a mean age of 40 years. Type 3 enhancement was seen in five postmenopausal patients (13%) with a mean age of 53 years and was characterized by faint diffuse enhancement. In the cervix, a zonal pattern of enhancement defining inner and outer stroma was seen in 23 patients (61%). Fifteen patients were premenopausal and eight were postmenopausal. Conclusion: In this study, we have shown a transitory zonal distribution of the contrast in the myometrium and cervix using dynamic contrast-enhanced helical CT

  12. CT angiography. Abdominal CT using intravenous aortography for contrast enhancement

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    Nagai, J; Nakauma, Y; Egawa, J; Kawamura, M [Teikyo Univ., Tokyo (Japan). Faculty of Medicine

    1980-04-01

    To obtain imaging effects close to those of abdominal aortography and investigate a technique with little invasion to patients, intravenous aortography was applied to contrast enhancement (CE) in abdominal CT, and its usefulness was discussed. Intravenous aortography could clearly visualize lesions with rich neovascularity such as hepatocellular carcinoma and renal cell carcinoma. Differing from a drip infusion method, this method has complexities in its technique that contrast medium is injected at once, blood circulation time which is represented by the time between the injection and the time when the patients feel bitterness (10 - 12 seconds) must be measured before CE, and scanning begins 2 seconds before the patients feel bitterness. However, the invasion to patients due to this method is slight, and the capacity of this method to visualize neovascularity is superior to CE by a drip infusion method. Therefore, qualitative diagnosis by CT will be improved by using this method together with a drip infusion method.

  13. CT of hepatocellular carcinoma. Analysis of contrast-enhanced CT using CT arteriography

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    Nakamura, H; Tanaka, T; Hori, S; Tokunaga, K; Yoshioka, H [Osaka Univ. (Japan). Faculty of Medicine

    1981-02-01

    Although changes in the CT appearance resulting from contrast enhancement (CE) for hepatocellular carcinoma have been considered in association with vascularity of tumors, no detailed studies have yet been made. We analyzed changes in the CT appearance following CE by comparing with hepatic arteriogram and CT arteriogram (CTA) performed during intraarterial infusion of contrast medium. When tumors showing low density in the plain CT were enhanced by contrast, the results were variable, ranging from intensification of the low density to replacement by high density, and the results were classified into L/sub 0/ to L/sub 3/ according to vascularity of tumors. The results after CE could also be classified into I/sub 0/ to I/sub 3/ when tumors showed isodensity in the plain CT. There was a correlation between vascularity presumed from CE and vascularity by CTA. It may be concluded that tumor vascularity could be estimated by the findings of CE which might indicate a possibility of qualitative diagnosis of tumors.

  14. Calcium scoring in unenhanced and enhanced CT data of the aorta-iliacal arteries: impact of image acquisition, reconstruction, and analysis parameter settings

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    Komen, N. (Dept. of Surgery, Univ. Medical Center Rotterdam, Erasmus MC, Rotterdam (Netherlands); Dept. of Surgery, Univ. Hospital Antwerp, Edegem (Belgium)), email: nielskomen@hotmail.com; Klitsie, P.; Jeekel, J.; Lange, J.F. (Dept. of Surgery, Univ. Medical Center Rotterdam, Erasmus MC, Rotterdam (Netherlands)); Hermans, J.J.; Niessen, W.J. (Dept. of Radiology, Univ. Medical Center Rotterdam, Erasmus MC, Rotterdam (Netherlands)); Kleinrensink, G.J. (Dept. of Neurosciences and Anatomy, Univ. Medical Center Rotterdam, Erasmus MC, Rotterdam (Netherlands))

    2011-11-15

    Background. Several studies have been published on the matter of abdominal aortic and iliac calcifications and the association to clinical entities such as diabetes mellitus and renal failure. However, comparing of these studies is questionable since quantification methods for atherosclerosis differ. Purpose. To evaluate the effect of image acquisition settings, reconstruction parameters, and analysis methods on calcium quantification in the abdominal aorta. Material and Methods. Calcium scores were retrospectively determined on standardized abdominal CT scans of 15 patients. Two researchers obtained calcium scores with 10 different lower thresholds (LT) (130, 145, 160, 175, 200, 300, 400, 500, 600, 1000) in CT scans with and without contrast enhancement, with slice thicknesses (ST) varying between 2.0-5.0 mm for the non-contrast-enhanced series and between 1.0-5.0 mm for the contrast-enhanced series. In addition calcium scores obtained with two convolution kernels (B10f, B20f) were compared. Inter-observer variability was calculated. Results. Calcium scoring at higher STs is overestimated compared to smaller STs and this effect was more pronounced with increasing calcium loads. Concerning the convolution kernel, scores obtained with kernel B10f were overestimated compared to kernel B20f. Increase of LT resulted in a decrease of the calcium score and scoring in contrast-enhanced series resulted in higher scores compared to non-contrast-enhanced series. These effects are more apparent in patients with higher calcium loads. Calcium scoring reproducibility with the reference standard is limited for the aorta-iliac trajectory, whereas scoring with the remaining settings is reproducible. Conclusion. Scores obtained with different settings cannot be compared. The inter-observer reproducibility was limited using the reference standard and practical difficulties were substantial. Scoring with higher LT, ST, and contrast enhancement is faster and has less practical

  15. Is contrast-enhanced CT indicated in acute head injury

    International Nuclear Information System (INIS)

    Mauser, H.W.; Nieuwenhuizen, O. van; Veiga-Pires, J.A.

    1984-01-01

    The authors discuss the value of intravenous contrast enhancement in CT scanning in acute head injury. In a series of seventy consecutive patients they conclude that no incremental information was obtained by performing contrast-enhanced CT scans in the acute phase of the head injury. (orig.)

  16. Osteoblastic Metastases Mimickers on Contrast Enhanced CT

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    Fahad Al-Lhedan

    2017-01-01

    Full Text Available Secondary osseous involvement in lymphoma is more common compared to primary bone lymphoma. The finding of osseous lesion can be incidentally discovered during the course of the disease. However, osseous metastases are infrequently silent. Detection of osseous metastases is crucial for accurate staging and optimal treatment planning of lymphoma. The aim of imaging is to identify the presence and extent of osseous disease and to assess for possible complications such as pathological fracture of the load-bearing bones and cord compression if the lesion is spinal. We are presenting two patients with treated lymphoma who were in complete remission. On routine follow-up contrast enhanced CT, there were new osteoblastic lesions in the spine worrisome for metastases. Additional studies were performed for further evaluation of both of them which did not demonstrate any corresponding suspicious osseous lesion. The patients have a prior history of chronic venous occlusive thrombosis that resulted in collaterals formation. Contrast enhancement of the vertebral body marrow secondary to collaterals formation and venous flow through the vertebral venous plexus can mimic the appearance of spinal osteoblastic metastases.

  17. PET/CT in malignant melanoma: contrast-enhanced CT versus plain low-dose CT

    International Nuclear Information System (INIS)

    Pfluger, Thomas; Schneider, Vera; Fougere, Christian la; Bartenstein, Peter; Weiss, Mayo; Melzer, Henriette Ingrid; Coppenrath, Eva; Berking, Carola

    2011-01-01

    The aim of this study was to evaluate the diagnostic value of contrast-enhanced CT (CECT) versus non-enhanced low-dose CT (NECT) in the staging of advanced malignant melanoma with 18 F-fluordeoxyglucose (FDG) positron emission tomography (PET)/CT. In total, 50 18 F-FDG PET/CT examinations were performed in 50 patients with metastasized melanoma. For attenuation correction, whole-body NECT was performed followed by diagnostic CECT with contrast agent. For the whole-body PET, 18 F-FDG was applied. Criteria for evaluation were signs of vital tumour tissue (extent of lesions, contrast enhancement, maximum standardized uptake value >2.5). Findings suspicious for melanoma were considered lesions. NECT, CECT and 18 F-FDG PET were evaluated separately, followed by combined analysis of PET/NECT and PET/CECT. Findings were verified histologically and/or by follow-up (>6 months). Overall, 232 lesions were analysed, and 151 proved to be metastases. The sensitivity of NECT, CECT, PET, PET/NECT and PET/CECT was 62, 85, 90, 97 and 100%, and specificity was 52, 63, 88, 93 and 93%, respectively. Compared to CECT, NECT obtained additional false-negative results: lymph node (n = 19) and liver/spleen metastases (n = 9). Misinterpreted physiological structures mainly caused additional false-positive findings (n = 17). In combined analysis of PET/NECT, six false-positive [other tumours (n = 2), inflammatory lymph nodes (n = 2), inflammatory lung lesion (n = 1), blood vessel (n = 1)] and five false-negative findings [liver (n = 3), spleen (n = 1), lymph node metastases (n = 1)] remained. On PET/CECT, six false-positive [inflammatory lymph nodes (n = 3), other tumours (n = 2), inflammatory lung lesion (n = 1)] and no false-negative findings occurred. However, additional false findings on PET/NECT (6 of 232) did not change staging compared to PET/CECT. Our results indicate that it is justified to perform PET/NECT instead of PET/CECT for melanoma staging. (orig.)

  18. Cranial CT revisited: do we really need contrast enhancement?

    International Nuclear Information System (INIS)

    Demaerel, P.; Buelens, C.; Wilms, G.; Baert, A.L.

    1998-01-01

    The aim of this study was to define guidelines for intravenous contrast administration in cranial CT, as currently there are no recent guidelines based on a large series of patients. In 1900 consecutive patients (1480 adults and 420 children) pre- and post-contrast scan was analysed in order to assess the contribution of contrast enhancement to the diagnosis. The findings were grouped according to whether abnormalities were seen on the pre- and/or post-contrast scan, or whether no abnormalities were seen at all. Sensitivity, specificity, positive predictive value, negative predictive value and accurracy of a pre-contrast scan were used to determine validity. Intravenous contrast enhancement only contributes to the diagnosis if a suspicious abnormality is seen on the unenhanced scan or in the appropriate clinical setting (33.6 %). In the remaining patients (65.6 %) there is no diagnostic contribution, except for a small number of abnormalities (0.8 %). These are often anatomical variants and have no therapeutic impact. The number of contrast-enhanced cranial CT examinations can significantly be reduced by using four general guidelines for contrast administration resulting in considerable cost savings without affecting the quality of service to the patient. These guidelines are defined by the clinical findings/presentation or by the findings on the unenhanced scan. The number of contrast-related complications will be reduced, which may have medicolegal implications. These guidelines can be applied in any radiology department. (orig.) (orig.)

  19. Late Adverse Events after Enhanced and Unenhanced MRI and CT

    DEFF Research Database (Denmark)

    Azzouz, Manal; Rømsing, Janne; Thomsen, Henrik S.

    2014-01-01

    Prospective evaluation of frequency of late and very late adverse events in patients undergoing enhanced or unenhanced magnetic resonance imaging (MRI) or computed tomography (CT). The imaging procedure was performed according to the protocols of the department. All patients were contacted three...... of LAEs was significantly higher in the enhanced MRI (38%) and CT (27%) groups than unenhanced MRI (20%) and CT (16%) groups. The frequency of nausea, dizziness, abdominal pain and diarrhoea was significantly higher in the enhanced MRI group than in the MRI control group, while taste sensation...

  20. Non-enhanced CT versus contrast-enhanced CT in integrated PET/CT studies for nodal staging of rectal cancer

    International Nuclear Information System (INIS)

    Tateishi, Ukihide; Maeda, Tetsuo; Morimoto, Tsuyoshi; Miyake, Mototaka; Arai, Yasuaki; Kim, E.E.

    2007-01-01

    The purpose of the present study was to determine the diagnostic accuracy of non-enhanced CT and contrast-enhanced CT in integrated PET/CT studies for preoperative nodal staging of rectal cancer. Retrospective analysis was performed in 53 patients with pathologically proven rectal cancer who had been referred for preoperative staging. All patients underwent integrated PET/CT consisting of non-enhanced and contrast-enhanced CT followed by whole-body fluorine-18-fluorodeoxyglucose ([ 18 F]FDG) PET. Both non-enhanced and contrast-enhanced PET/CT images were evaluated separately by two observers in consensus. The reference standard was histopathologic results. For nodal staging of rectal cancer, we compared diagnostic accuracy on a per-patient basis between the two modalities. Nodal staging was correctly determined with non-enhanced studies in 37 patients (70%) and with contrast-enhanced studies in 42 patients (79%). On a per-patient basis, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of regional lymph node staging were 85%, 68%, 83%, 72%, and 79%, respectively, with contrast-enhanced studies, and 85%, 42%, 73%, 62%, and 70%, respectively, with non-enhanced studies. The difference in the accuracy of nodal staging between the two modalities was not significant (p = 0.063). Compared with non-enhanced studies, contrast-enhanced studies determined more correctly the status of pararectal lymph nodes (p 0.002), internal iliac lymph nodes (p = 0.004), and obturator lymph nodes (p < 0.0001). Contrast-enhanced PET/CT is superior to non-enhanced PET/CT for precise definition of regional nodal status in rectal cancer. (orig.)

  1. PET/CT and contrast enhanced CT in single vs. two separate sessions: a cost analysis study.

    Science.gov (United States)

    Picchio, M; Mansueto, M; Crivellaro, C; Guerra, L; Marcelli, S; Arosio, M; Sironi, S; Gianolli, L; Grimaldi, A; Messa, C

    2012-06-01

    Aim of the study was to quantify the economic impact of PET/CT and contrast enhanced (c.e.) CT performed in a single session examination vs. stand-alone modalities in oncological patients. One-hundred-forty-five cancer patients referred to both PET/CT and c.e. CT, to either stage (N.=46) or re-stage (N.=99) the disease, were included. Seventy-two/145 performed both studies in a single session (innovative method) and 73/145 in two different sessions (traditional method). The cost-minimization analysis was performed by evaluating: 1) institutional costs, data obtained by hospital accountability (staff, medical materials, equipment maintenance and depreciation, departments utilities); 2) patients costs, data obtained by a specific survey provided to patients (travel, food, accommodation costs, productivity loss). Economic data analysis showed that the costs for innovative method was lower than those of traditional method, both for Institution (106 € less per test) and for patient (21 € less per patient). The loss of productivity for patient and caregivers resulted lower for the innovative method than the traditional method (3 work-hour less per person). PET/CT and c.e. CT performed in a single session is more cost-effective than stand-alone modalities, by reducing both Institutional and patients costs. These advantages are mainly due to lower Institutional cost (single procedure) and to lower cost related to travel and housing.

  2. FDG-PET/contrast-enhanced CT as a post-treatment tool in head and neck squamous cell carcinoma: comparison with FDG-PET/non-contrast-enhanced CT and contrast-enhanced CT

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    Suenaga, Yuko; Kitajima, Kazuhiro; Sugimura, Kazuro [Kobe University Graduate School of Medicine, Department of Radiology, Kobe (Japan); Ishihara, Takeaki; Sasaki, Ryohei [Kobe University Graduate, School of Medicine, Department of Radiology, Division of Radiation Oncology, Kobe (Japan); Otsuki, Naoki; Nibu, Ken-ichi [Kobe University Graduate, School of Medicine, Department of Otolaryngology-Head and Neck Surgery, Kobe (Japan); Minamikawa, Tsutomu [Kobe University Graduate School of Medicine, Department of Oral and Maxillofacial Surgery, Kobe (Japan); Kiyota, Naomi [Kobe University Hospital, Department of Medical Oncology and Hematology, Kobe (Japan)

    2016-04-15

    To evaluate the accuracy of PET/CT using {sup 18}F-fluorodeoxyglucose (FDG) with IV contrast for suspected recurrent head and neck squamous cell carcinoma (HNSCC). One hundred and seventy patients previously treated for HNSCC underwent PET/CT, consisting of non-contrast-enhanced and contrast-enhanced CT, to investigate suspected recurrence. Diagnostic performance of PET/contrast-enhanced CT (PET/ceCT), PET/non-contrast-enhanced CT (PET/ncCT) and contrast-enhanced CT (ceCT) for local or regional recurrence, distant metastasis, overall recurrence and second primary cancer was evaluated. The reference standard included histopathology, treatment change and imaging follow-up. The patient-based areas under the receiver operating characteristic curves (AUC) for ceCT, PET/ncCT and PET/ceCT were 0.82, 0.96 and 0.98 for local recurrence, 0.73, 0.86 and 0.86 for regional recurrence, 0.86, 0.91 and 0.92 for distant metastasis, 0.72, 0.86 and 0.87 for overall recurrence, and 0.86, 0.89 and 0.91 for a second primary cancer. Both PET/ceCT and PET/ncCT statistically showed larger AUC than ceCT for recurrence, and the difference between PET/ceCT and PET/ncCT for local recurrence reached a significant level (p = 0.039). The accuracy of PET/ceCT for diagnosing overall recurrence was high, irrespective of the time interval after the last treatment (83.3-94.1 %). FDG-PET/CT was a more accurate HNSCC restaging tool than ceCT. The added value of ceCT at FDG-PET/CT is minimal. (orig.)

  3. Recurrent postoperative sciatica: Evaluation with MR imaging and enhanced CT

    International Nuclear Information System (INIS)

    Duoauferrier, R.; Frocrain, L.; Husson, J.L.

    1987-01-01

    The authors prospectively compared surface coil MR (SCMR) imaging and CT with iodinate contrast enhancement in 50 patients with recurrent postoperative sciatica. Of the 50 patients enrolled in the study, surgical treatment was elected in 27 patients after independent examination of SCMR imaging and enhanced CT. All predictions made with the 27 SCMR images were surgically confirmed. The surgical findings were 20 recurrent disk herniations, five recurrent disk herniations with scar tissue, one disk herniation above the level of diskectomy, and one disk herniation below the level of diskectomy. The surgical findings of the 12 patients who had scar tissue on CT were seven recurrent disk herniations, four recurrent disk herniations with scar tissue, and one disk herniation below the operated level. SCMR imaging was more sensitive and more specific than CT to differentiate scar tissue from recurrent disk herniation

  4. Low-dose non-enhanced CT versus full-dose contrast-enhanced CT in integrated PET/CT studies for the diagnosis of uterine cancer recurrence

    Energy Technology Data Exchange (ETDEWEB)

    Kitajima, Kazuhiro [Institute of Biomedical Research and Innovation, Department of PET Diagnosis, Kobe (Japan); Kobe University Graduate School of Medicine, Department of Radiology, Kobe (Japan); Suzuki, Kayo [Institute of Biomedical Research and Innovation, Department of PET Diagnosis, Kobe (Japan); Nakamoto, Yuji [Kyoto University Hospital, Department of Diagnostic Radiology, Kyoto (Japan); Onishi, Yumiko; Sakamoto, Setsu; Sugimura, Kazuro [Kobe University Graduate School of Medicine, Department of Radiology, Kobe (Japan); Senda, Michio [Institute of Biomedical Research and Innovation, Department of Molecular Imaging, Kobe (Japan); Kita, Masato [Kobe City Medical Center General Hospital, Department of Obstetrics and Gynecology, Kobe (Japan)

    2010-08-15

    To evaluate low-dose non-enhanced CT (ldCT) and full-dose contrast-enhanced CT (ceCT) in integrated {sup 18}F-fluorodeoxyglucose (FDG) PET/CT studies for restaging of uterine cancer. A group of 100 women who had undergone treatment for uterine cervical (n=55) or endometrial cancer (n=45) underwent a conventional PET/CT scans with ldCT, and then a ceCT scan. Two observers retrospectively reviewed and interpreted the PET/ldCT and PET/ceCT images in consensus using a three-point grading scale (negative, equivocal, or positive) per patient and per lesion. Final diagnoses were obtained by histopathological examination, or clinical follow-up for at least 6 months. Patient-based analysis showed that the sensitivity, specificity and accuracy of PET/ceCT were 90% (27/30), 97% (68/70) and 95% (95/100), respectively, whereas those of PET/ldCT were 83% (25/30), 94% (66/70) and 91% (91/100), respectively. Sensitivity, specificity and accuracy did not significantly differ between two methods (McNemar test, p=0.48, p=0.48, and p=0.13, respectively). There were 52 sites of lesion recurrence: 12 pelvic lymph node (LN), 11 local recurrence, 8 peritoneum, 7 abdominal LN, 5 lung, 3 supraclavicular LN, 3 liver, 2 mediastinal LN, and 1 muscle and bone. The grading results for the 52 sites of recurrence were: negative 5, equivocal 0 and positive 47 for PET/ceCT, and negative 5, equivocal 4 and positive 43 for PET/ldCT, respectively. Four equivocal regions by PET/ldCT (local recurrence, pelvic LN metastasis, liver metastasis and muscle metastasis) were correctly interpreted as positive by PET/ceCT. PET/ceCT is an accurate imaging modality for the assessment of uterine cancer recurrence. Its use reduces the frequency of equivocal interpretations. (orig.)

  5. Solitary pulmonary nodules: impact of functional CT on the cost-effectiveness of FDG-PET

    International Nuclear Information System (INIS)

    Miles, K.A.; Keith, C.J.; Wong, D.C.; Griffiths, M.R.

    2002-01-01

    Full text: FDG-PET has been shown to be cost-effective for the evaluation of solitary pulmonary nodules (SPNs) in Australia. This study evaluates the impact on cost-effectiveness produced by incorporating a novel CT technique, functional CT, into diagnostic algorithms for characterisation of SPNs. Four diagnostic strategies were evaluated using decision tree sensitivity analysis. The first strategy comprised patients undergoing conventional CT alone (CT). The second comprised conventional CT followed by functional CT study (FCT), when the SPN was not benign on conventional CT. The third strategy comprised conventional CT, which if positive is followed by FDG-PET (PET) and a fourth strategy where patients with a positive conventional CT undergo functional CT, which if positive also undergo FDG-PET (FCT+PET). Values for disease prevalence and diagnostic accuracy of PET, CT and functional CT were obtained from a literature review, using Australia values where available. Procedure costs were derived from the Medicare Benefits Schedule and DRG Cost Weights for Australian public hospitals. The cost per patient, accuracy and Incremental Cost-Accuracy Ratio (ICAR) were determined for each strategy. Sensitivity analysis evaluated the effect of disease prevalence on cost-effectiveness. Results: At the prevalence of malignancy reported from Australian series (54%), the FCT strategy incurs the least cost ($5560/patient), followed by the FCT+PET ($5910/patient). The FCT+PET strategy is the most cost-effective strategy with an ICAR of $12059/patient, followed by the PET strategy with an ICAR of $12300/patient. At levels of disease prevalence below 54% the above relationship for cost-effectiveness remains the same. For high levels of disease prevalence, CT or FCT are found to be more cost-effective. At typical prevalence of malignancy the cost-effectiveness of PET is enhanced by the addition of functional CT, but at high prevalence functional CT alone is most cost

  6. Accuracy Enhancement of CT Measurements using Data Filtering

    DEFF Research Database (Denmark)

    Stolfi, Alessandro; Kallasse, Maarja-Helena; Carli, Lorenzo

    2016-01-01

    This paper describes the impact of data filtering on CT capability to inspect assemblies. The investigation was carried out using an industrial multi-material assembly provided by Novo Nordisk A/S. The assembly comprises two parts made of polyoxymethylene (POM) and of an alloy comprising polycarb...

  7. Restaging of patients with lymphoma. Comparison of low dose CT (20 mAs) with contrast enhanced diagnostic CT in combined [18F]-FDG PET/CT

    International Nuclear Information System (INIS)

    Fougere, C. la; Pfluger, T.; Schneider, V.; Hacker, M.; Broeckel, N.; Bartenstein, P.; Tiling, R.; Morhard, D.; Hundt, W.; Becker, C.

    2008-01-01

    Aim: assessment of the clinical benefit of i.v. contrast enhanced diagnostic CT (CE-CT) compared to low dose CT with 20 mAs (LD-CT) without contrast medium in combined [ 18 F]-FDG PET/CT examinations in restaging of patients with lymphoma. Patients, methods: 45 patients with non-Hodgkin lymphoma (n = 35) and Hodgkin's disease (n = 10) were included into this study. PET, LD-CT and CE-CT were analyzed separately as well as side-by-side. Lymphoma involvement was evaluated separately for seven regions. Indeterminate diagnoses were accepted whenever there was a discrepancy between PET and CT findings. Results for combined reading were calculated by rating indeterminate diagnoses according the suggestions of either CT or PET. Each patient had a clinical follow-up evaluation for > 6 months. Results: region-based evaluation suggested a sensitivity/specificity of 66/93% for LD-CT, 87%/91% for CE-CT, 95%/96% for PET, 94%/99% for PET/LD-CT and 96%/99% for PET/CE-CT. The data for PET/CT were obtained by rating indeterminate results according to the suggestions of PET, which turned out to be superior to CT. Lymphoma staging was changed in two patients using PET/CE-CT as compared to PET/LD-CT. Conclusion: overall, there was no significant difference between PET/LD-CT and PET/CE-CT. However, PET/CE-CT yielded a more precise lesion delineation than PET/LD-CT. This was due to the improved image quality of CE-CT and might lead to a more accurate investigation of lymphoma. (orig.)

  8. Recurrent postoperative sciatica: Evaluation with MR imaging and enhanced CT

    International Nuclear Information System (INIS)

    Duvauferrier, R.; Frocain, L.; Husson, J.L.

    1987-01-01

    The authors prospectively compared MR imaging performed with a surface coil and CT performed with iodinated contrast agent enhancement in 50 patients with recurrent postoperative sciatica. Surgical decision was an objective measure of accuracy. Surgical treatment was selected for 27 patients. All 27 underwent MR imaging. The 15 patients who underwent CT/surgical treatment were included in the 27 indications of SCMR. All predictions based on MR imaging findings were confirmed at surgery. There were 25 recurrent disk herniations, including five with scar tissue, and two disk herniations above or below the level of the diskectomy. In the 12 patients with scar tissue detected on CT there were seven recurrent disk hernitions, four recurrent disk herniations with scar tissue, and one disk herniation below the level of the diskectomy

  9. Intense Adrenal Enhancement: A CT Feature of Cardiogenic Shock

    International Nuclear Information System (INIS)

    Hrabak-Paar, Maja

    2016-01-01

    In this report, images of intense adrenal enhancement in a 79-year-old female patient with right-sided heart failure and severe tricuspid insufficiency are presented. Only two cases of intense adrenal enhancement as a sign of cardiogenic shock were previously reported in the literature. Intense adrenal enhancement could be one of the earliest CT signs of cardiogenic shock. Its presence should be immediately reported to the referring physician as a sign of significant hemodynamic instability warranting early critical-care management

  10. Intense Adrenal Enhancement: A CT Feature of Cardiogenic Shock

    Energy Technology Data Exchange (ETDEWEB)

    Hrabak-Paar, Maja, E-mail: maja.hrabak.paar@mef.hr [University of Zagreb School of Medicine, Department of Diagnostic and Interventional Radiology, University Hospital Center Zagreb (Croatia)

    2016-02-15

    In this report, images of intense adrenal enhancement in a 79-year-old female patient with right-sided heart failure and severe tricuspid insufficiency are presented. Only two cases of intense adrenal enhancement as a sign of cardiogenic shock were previously reported in the literature. Intense adrenal enhancement could be one of the earliest CT signs of cardiogenic shock. Its presence should be immediately reported to the referring physician as a sign of significant hemodynamic instability warranting early critical-care management.

  11. CT findings in autoimmune pancreatitis: assessment using multiphase contrast-enhanced multisection CT

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, K., E-mail: Kojiro@med.nagoya-u.ac.j [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Itoh, S. [Department of Radiology, Nagoya Hirokoji Clinic, Nagoya (Japan); Nagasaka, T. [Departments of Medical Technology, Nagoya University School of Health Science, Nagoya (Japan); Ogawa, H.; Ota, T.; Naganawa, S. [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan)

    2010-09-15

    Aim: To assess the spectrum of findings using multiphase contrast-enhanced computed tomography (CT) in patients with autoimmune pancreatitis (AIP). Materials and methods: Fifty patients (four female and 46 male, mean age 65 years) were retrospectively identified from consecutive patients with abnormal CT findings of the pancreas and negative work-up for known causes. These patients had at least one finding supporting the diagnosis of AIP: serological abnormality, histopathological abnormality, or response to steroid. Two radiologists evaluated multiphase contrast-enhanced CT images in consensus. Results: The pancreas showed diffuse enlargement (n = 16; 32%), focal enlargement (n = 18; 36%), or no enlargement (n = 16; 32%). Forty-nine (98%) patients showed abnormal contrast enhancement in the affected pancreatic parenchyma, including hypoattenuation during the pancreatic phase (n = 45; 90%) and hyperattenuation during the delayed phase (n = 39; 87%). The following findings were also seen in the pancreas: a capsule-like rim (n = 24; 48%); no visualization of the main pancreatic duct lumen (n = 48; 96%); ductal enhancement (n = 26; 52%); upstream dilatation of the main pancreatic duct (n = 27; 54%); upstream atrophy of the pancreatic parenchyma (n = 27; 54%); calcification (n = 7; 14%); and cysts (n = 5; 10%). Forty-two (84%) patients showed one or more of the following extrapancreatic findings: biliary duct or gallbladder abnormality (n = 40; 80%); peripancreatic (n = 8; 16%) or para-aortic (n = 10; 20%) soft-tissue proliferation; and renal involvement (n = 15; 30%). Conclusion: Patients with AIP presented with a variety of CT findings in the pancreas and the extrapancreatic organs. The present study highlights pancreatic ductal enhancement in a subset of patients with AIP.

  12. Impact of {sup 18}F-FDG PET/CT on the management of adrenocortical carcinoma: analysis of 106 patients

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, Satoshi; Macapinlac, Homer A.; Chuang, Hubert H. [The University of Texas MD Anderson Cancer Center, Department of Nuclear Medicine, Houston, TX (United States); Balachandran, Aparna [The University of Texas MD Anderson Cancer Center, Department of Diagnostic Radiology, Houston, TX (United States); Habra, Mouhammed Amir [The University of Texas MD Anderson Cancer Center, Department of Endocrine Neoplasia and Hormonal Disorders, Houston, TX (United States); Phan, Alexandria T. [The University of Texas MD Anderson Cancer Center, Department of Gastrointestinal Medical Oncology, Houston, TX (United States); Bassett, Roland L. [The University of Texas MD Anderson Cancer Center, Department of Biostatistics, Houston, TX (United States)

    2014-11-15

    Adrenocortical carcinoma (ACC) is a rare and aggressive malignancy. Limited data are available about on value of {sup 18}F-FDG PET/CT in ACC. We evaluated the impact of PET/CT on the management of ACC. We performed a retrospective review in patients with ACC who had undergone PET/CT. The impact of PET/CT on the management plan was evaluated by comparing the findings on PET/CT to the findings on contrast-enhanced CT. The sensitivity, specificity, and accuracy of each form of imaging were calculated. The correlations between PET/CT parameters, including maximum standardized uptake value (SUV{sub max}), total lesion glycolysis, and decline in SUV{sub max} after chemotherapy, and clinical outcome were evaluated. Included in the analysis were 106 patients with 180 PET/CT scans. Of the 106 patients, 7 underwent PET/CT only for initial staging, 84 underwent PET/CT only for restaging, and 15 underwent PET/CT for both initial staging and restaging. PET/CT changed the management plan in 1 of 22 patients (5 %) at initial staging and 9 of 99 patients (9 %) at restaging. In 5 of the patients in whom PET/CT changed the management plan, PET/CT showed response to chemotherapy but contrast-enhanced CT showed stable disease. Sensitivity, specificity, and accuracy were 100 %, 100 %, and 100 % for PET/CT at initial staging; 92.6 %, 100 %, and 96.4 % for CT at initial staging; 98.4 %, 100 %, and 99.5 % for PET/CT at restaging; and 96.8 %, 98.6 %, and 98.0 % for CT at restaging, respectively. No PET/CT parameters were associated with survival at either initial diagnosis or recurrence. PET/CT findings could substantially change the management plan in a small proportion of patients with ACC. Although lesion detection was similar between PET/CT and CT, PET/CT may be preferred for chemotherapeutic response assessment because it may predict response before anatomic changes are detected on CT. (orig.)

  13. Performance of integrated FDG-PET/contrast-enhanced CT in the staging and restaging of colorectal cancer: Comparison with PET and enhanced CT

    International Nuclear Information System (INIS)

    Dirisamer, Albert; Halpern, Benjamin S.; Floery, Daniel; Wolf, Florian; Beheshti, Mohsen; Mayerhoefer, Marius E.; Langsteger, Werner

    2010-01-01

    Objective: The purpose of this study was to assess the diagnostic value of PET/CT as a one step examination in patients with colorectal cancer. Therefore we proved whether diagnostic PET/CT adds information over PET or contrast-enhanced CT alone for staging or restaging of patients with colorectal cancer. Methods: Seventy-three patients (46 males and 27 females; age range: 50-81 years; mean age: 67 years) with known colorectal cancer underwent 18F-FDG-PET/CT for staging or restaging. Results: Of the 73 patients 26 patients underwent PET/CT for staging and 47 for restaging. 266 metastases could be detected in 60 patients. Contrast-enhanced PET/CT had a lesion-based sensitivity of 100%, contrast-enhanced CT of 91% and PET of 85%. PET/CT identified 2 lesions as false positive. PET/CT could also reach a patient-based sensitivity of 100%, which was superior to contrast-enhanced CT and PET. Conclusion: Our study clearly demonstrated the added value of contrast-enhanced PET/CT in staging and restaging patients with colorectal cancer over CT and PET alone.

  14. A prolapsed cervical disc with diffuse contrast enhancement on CT

    International Nuclear Information System (INIS)

    Goto, Jun; Shinpo, Tomoyuki; Inoue, Kiyoharu; Shigeno, Taku; Ochiai, Chikayuki

    1985-01-01

    A 48-year-old woman with the C5/6 disc herniation was reported. She had noticed vague pains in the left shoulder a half year earlier. Neurological examination showed left lower cervical radicular pains and incomplete Brown-Sequard syndrome of the same side. The disc herniation was diagnosed by myelography and discography. On the CT examination, surprisingly, the prolapsed disc was homogenously enhanced after the administration of intravenous contrast medium. The vertebral angiography showed increased vascularity behind the C5/6 intervertebral space. At operation, a prolapsed nucleus pulposus with proliferated connective tissue was found and curetted. The etiology of contrast enhancement was discussed. (author)

  15. Contrast-enhanced dedicated breast CT detection of invasive breast cancer preceding mammographic diagnosis

    Directory of Open Access Journals (Sweden)

    Nicolas D. Prionas, MD, PhD

    2015-01-01

    Full Text Available Dedicated breast computed tomography (bCT generates high-resolution, three-dimensional images of the pendent uncompressed breast. Intravenous iodinated contrast during bCT provides additional physiologic information. In this case, a 10.0-mm invasive ductal carcinoma was visualized using contrast-enhanced breast CT one year before mammographic detection. Mammography four months before bCT was negative. The bCT contrast enhancement pattern closely matched the dynamic contrast-enhanced MRI obtained after diagnosis. Lesion enhancement at contrast-enhanced breast CT matched previously published enhancement values of breast cancer. Contrast-enhanced dedicated bCT provided high-resolution tomographic images and physiologic contrast enhancement data that facilitated the detection of an early breast cancer.

  16. Applications of contrast enhanced CT through external jugular access

    International Nuclear Information System (INIS)

    Xu Qiaolan; Zou Wenxing; Chen Meixia; Xie Hongbo

    2005-01-01

    Objective: A retrospective analysis and evaluation for the effects of contrast enhanced computed tomography through external jugular access. Methods: 1250 cases (male 692 and female 558) underwent CT contrast enhanced examination were retrospectively reviewed from May, 2002 to Oct, 2002. The patients aged from 12 to 86 years, averagely 49 years. Contrast agent (Ultravist) was given through an intravenous catheter placed in the cubital vein. Precise injection rates were ensured by a power injector (Medrad MCT310, USA). Excellent enhancement was achieved with this protocol in most of the patients, while external jugular access was established in 96 cases because it was unable to setup a cubital venous access. Results: Good enhancement were acquired when 96 cases of contrast agent injected through external jugular vein. And the external jugular access was setup successfully with a single puncture. Conclusion: It is a common occasion when patient undergoing contrast enhanced CT scan is in poor conditions: debility, cachexia, or with complication of chemotherapy or radiation therapy, which often results in invalidity of cabital venous access, and consequently, making bolus injection impossible. The external jugular vein is a large and central blood vessel, which is easy to setup an access. In our experience, an external jugular access should be recommended as a substitution if the cubital venous access is not available. (authors)

  17. Applications of contrast enhanced CT through external jugular access

    Energy Technology Data Exchange (ETDEWEB)

    Qiaolan, Xu; Wenxing, Zou; Meixia, Chen; Hongbo, Xie [The First Affiliated Hospital of Sun Yat-sen University, Guangzhou (China). Dept. of Radiology

    2005-09-15

    Objective: A retrospective analysis and evaluation for the effects of contrast enhanced computed tomography through external jugular access. Methods: 1250 cases (male 692 and female 558) underwent CT contrast enhanced examination were retrospectively reviewed from May, 2002 to Oct, 2002. The patients aged from 12 to 86 years, averagely 49 years. Contrast agent (Ultravist) was given through an intravenous catheter placed in the cubital vein. Precise injection rates were ensured by a power injector (Medrad MCT310, USA). Excellent enhancement was achieved with this protocol in most of the patients, while external jugular access was established in 96 cases because it was unable to setup a cubital venous access. Results: Good enhancement were acquired when 96 cases of contrast agent injected through external jugular vein. And the external jugular access was setup successfully with a single puncture. Conclusion: It is a common occasion when patient undergoing contrast enhanced CT scan is in poor conditions: debility, cachexia, or with complication of chemotherapy or radiation therapy, which often results in invalidity of cabital venous access, and consequently, making bolus injection impossible. The external jugular vein is a large and central blood vessel, which is easy to setup an access. In our experience, an external jugular access should be recommended as a substitution if the cubital venous access is not available. (authors)

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

    Science.gov (United States)

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

    2005-01-01

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

  19. Demonstration of pulmonary embolism with gadolinium-enhanced spiral CT

    Energy Technology Data Exchange (ETDEWEB)

    Coche, E.E.; Hammer, F.D.; Goffette, P.P. [Dept. of Radiology, St. Luc University Hospital, Brussels (Belgium)

    2001-11-01

    The authors report a case of successful detection of pulmonary embolism using gadolinium-enhanced spiral CT (Gadodiamide, 0.4 mmol/kg, 2 ml/s, delay 18 s) in a 77-year-old woman, with previous allergy to iodinated contrast medium, and renal failure, who presented with pulmonary arterial hypertension. Doppler ultrasound of the lower limbs was first performed and revealed a deep venous thrombosis of the right lower limb. To establish if venous thrombosis was the cause of pulmonary hypertension and to confirm that pulmonary endarterectomy was not indicated in this situation, several imaging modalities were performed. Lung scintigraphy and MRI were non-diagnostic. Gadolinium-enhanced spiral CT demonstrated a large thrombus located proximally and in a segmental artery of the right lower lobe. This case illustrates the potential usefulness of gadolinium as alternative contrast agent with spiral CT to diagnose pulmonary embolism and elucidate the cause of pulmonary arterial hypertension in a patient with some contraindications for iodinated contrast medium injection. (orig.)

  20. Demonstration of pulmonary embolism with gadolinium-enhanced spiral CT

    International Nuclear Information System (INIS)

    Coche, E.E.; Hammer, F.D.; Goffette, P.P.

    2001-01-01

    The authors report a case of successful detection of pulmonary embolism using gadolinium-enhanced spiral CT (Gadodiamide, 0.4 mmol/kg, 2 ml/s, delay 18 s) in a 77-year-old woman, with previous allergy to iodinated contrast medium, and renal failure, who presented with pulmonary arterial hypertension. Doppler ultrasound of the lower limbs was first performed and revealed a deep venous thrombosis of the right lower limb. To establish if venous thrombosis was the cause of pulmonary hypertension and to confirm that pulmonary endarterectomy was not indicated in this situation, several imaging modalities were performed. Lung scintigraphy and MRI were non-diagnostic. Gadolinium-enhanced spiral CT demonstrated a large thrombus located proximally and in a segmental artery of the right lower lobe. This case illustrates the potential usefulness of gadolinium as alternative contrast agent with spiral CT to diagnose pulmonary embolism and elucidate the cause of pulmonary arterial hypertension in a patient with some contraindications for iodinated contrast medium injection. (orig.)

  1. Detection of skeletal muscle metastasis: torso FDG PET-CT versus contrast-enhanced chest or abdomen CT.

    Science.gov (United States)

    So, Young; Yi, Jeong Geun; Song, Inyoung; Lee, Won Woo; Chung, Hyun Woo; Park, Jeong Hee; Moon, Sung Gyu

    2015-07-01

    Skeletal muscle metastasis (SMM) in cancer patients has not been sufficiently evaluated regarding prevalence and proper method of detection. To determine the prevalence of SMM and compare the diagnostic competencies for SMM of torso F-18 fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-CT) and contrast-enhanced chest or abdomen CT. We investigated 18,225 PET-CT studies of 6359 cancer patients performed from 2005 to 2012. The PET-CT studies describing potential SMM were retrieved and the corresponding medical records were reviewed. The gold standard for SMM was histopathologically-proven SMM or imaging study-based disease progression. The detectability of SMM was compared between PET-CT and contrast-enhanced CT. Twenty-six patients had 84 SMM lesions, representing a SMM prevalence of 0.41%. Lung cancer was the most common SMM-associated malignancy (54%) and the gluteal/pelvic girdle muscle was the most frequently involved SMM site (37%). All 84 SMM lesions were visualized on PET-CT (100%). Of these PET-CT positive 84 SMM lesions, 51 lesions were in the CT field of view (FOV) (61%), whereas 33 lesions were out of the CT FOV (39%). Among these 51 lesions, 17 lesions showed rim-enhancing nodules/masses (33%), eight lesions showed homogeneously enhancing nodules (16%), three lesions showed heterogeneously enhancing nodules (6%), and 23 SMM lesions (45%) were non-diagnostic by CT. All 51 SMM lesions within CT FOV were detected on PET-CT (100%), whereas only 28 were visualized on CT (54.9%), resulting in a significant difference (P SMM was revealed by PET-CT. The prevalence of SMM was as low as 0.41% in the current large cohort of cancer patients. Torso PET-CT was a more competent modality than contrast-enhanced CT in the detection of SMM. © The Foundation Acta Radiologica 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  2. Obscure pulmonary masses: bronchial impaction revealed by CT

    International Nuclear Information System (INIS)

    Pugatch, R.D.; Gale, M.E.

    1983-01-01

    Dilated bronchi impacted with mucus or tumor are recognized on standard chest radiographs because they are surrounded by aerated pulmonary parenchyma. When imaged in different projections, these lesions produce a variety of appearances that are generally familiar. This report characterizes less familiar computed tomographic (CT) findings in eight patients with pathologic bronchial distension of congenital, neoplastic, or infectious etiologies and correlates them with chest films. In seven patients, CT readily revealed dilated bronchi and/or regional lung hypodensity. In four of these cases, CT led to the initial suspicion of dilated bronchi. CT should be used early in the evaluation of atypical pulmonary mass lesions or to confirm suspected bronchial impaction because of the high probability it will reveal diagnostic features

  3. Towards enhanced CSR impact?

    International Nuclear Information System (INIS)

    Lunde, Leiv; Swanson, Phil

    2004-01-01

    This paper was produced by ECON Analysis in conjunction with the Fridtjof Nansen Institute (FNI) for the Norwegian Research Council's 'Petropol' programme. It is part of a joint project entitled, 'Oil companies and the new petroleum provinces: ethics, business and politics'. This paper examines the possibilities for partnerships between oil companies and multilateral government institutions to address the negative impacts of oil projects that often prevent the resulting revenues leading to social and economic benefits for the host country (author) (ml)

  4. Xenon-enhanced CT using subtraction CT: Basic and preliminary clinical studies for comparison of its efficacy with that of dual-energy CT and ventilation SPECT/CT to assess regional ventilation and pulmonary functional loss in smokers

    International Nuclear Information System (INIS)

    Ohno, Yoshiharu; Yoshikawa, Takeshi; Takenaka, Daisuke; Fujisawa, Yasuko; Sugihara, Naoki; Kishida, Yuji; Seki, Shinichiro; Koyama, Hisanobu; Sugimura, Kazuro

    2017-01-01

    Purpose: To prospectively and directly compare the capability for assessments of regional ventilation and pulmonary functional loss in smokers of xenon-ventilation CT obtained with the dual-energy CT (DE-CT) and subtraction CT (Sub-CT) Materials and methods: Twenty-three consecutive smokers (15 men and 8 women, mean age: 69.7 ± 8.7 years) underwent prospective unenhanced and xenon-enhanced CTs, the latter by Sub-CT and DE-CT methods, ventilation SPECT and pulmonary function tests. Sub-CT was generated from unenhanced and xenon-enhanced CT, and all co-registered SPECT/CT data were produced from SPECT and unenhanced CT data. For each method, regional ventilation was assessed by using a 11-point scoring system on a per-lobe basis. To determine the functional lung volume by each method, it was also calculated for individual sublets with a previously reported method. To determine inter-observer agreement for each method, ventilation defect assessment was evaluated by using the χ2 test with weighted kappa statistics. For evaluation of the efficacy of each method for pulmonary functional loss assessment, functional lung volume was correlated with%FEV 1 . Results: Each inter-observer agreement was rated as substantial (Sub-CT: κ = 0.69, p < 0.0001; DE-CT: κ = 0.64, p < 0.0001; SPECT/CT: κ = 0.64, p < 0.0001). Functional lung volume for each method showed significant to good correlation with%FEV 1 (Sub-CT: r = 0.72, p = 0.0001; DE-CT: r = 0.74, p < 0.0001; SPECT/CT: r = 0.66, p = 0.0006). Conclusion: Xenon-enhanced CT obtained by Sub-CT can be considered at least as efficacious as that obtained by DE-CT and SPECT/CT for assessment of ventilation abnormality and pulmonary functional loss in smokers.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-10-15

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

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

    International Nuclear Information System (INIS)

    Goo, Hyun Woo

    2017-01-01

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

  7. Xe enhanced CT in the human newborn infant

    International Nuclear Information System (INIS)

    Fuse, Yozen; Nemoto, Yuko; Shimizu, Mitsumasa; Uga, Naoki; Tada, Hiroshi; Fujii, Toshi; Machida, Keiichi; Kikuchi, Hideo; Izumi, Shigemitsu.

    1990-01-01

    With a cranial computed tomography (CT) using stable xenon gas as a diffusible tracer, we measured regional cerebral blood flow (rCBF) in 6 newborn infants with a variety of neurological abnormalities. Gestational ages and birthweights were 35 to 43 weeks and 2436 to 3540 g, respectively. Four infants exhibited hypoxic-ischemic encephalopathy (HIE), one infant had subdural hemorrhage and the other one was the infant with hyponatremia. A baseline CT was done during denitrogenation by 100% oxygen breathing and then a mixture of 35% xenon and 65% oxygen was breathed for 6 minutes. Six scans were obtained during the inhalation period then the infant was returned to breathing 100% oxygen and additional 7 scans were taken. Four samples of arterial blood were collected every 2 minutes before and during inhalation of the xenon gas. A rCBF was calculated with the changes of Hounsfield units in brain tissue and arterial blood. Relatively high blood flows in the region of the basal nuclei as well as decreased flows in the occipital white matter were observed in the infants with HIE. In an infant with subdural hemorrhage, the blood flows were markedly reduced in the areas adjacent to the lesion, including the basal nuclei, and frontal white matter in the opposite hemisphere. Xenon-enhanced CT by inhaling low concentration of the xenon gas enables to measure rCBF in the human newborn infants without no obvious side effect. (author)

  8. Diagnosis value of dual-phase contrast enhancement CT combined with virtual non-enhanced images by dual-energy CT in clear cell renal cell carcinoma

    International Nuclear Information System (INIS)

    Ma Zhoupeng; Zhou Jianjun; Liu Xueling; Wang Chun; Zhang Shunzhuang

    2012-01-01

    Objective: To explore the diagnostic value of dual-phase contrast enhancement CT combined with virtual non-enhanced images by dual-energy CT in clear cell renal cell carcinoma. Methods: Sixty patients who were suspected of clear cell renal cell carcinoma underwent non-enhanced CT and contrast enhancement CT of early interface-phase between cortex -medulla and parenchymal phase on a dual-energy CT. The true non-enhanced kidney CT (TNCT) was performed in a single-energy acquisition mode, but the dual-phase contrast enhancement CT were performed in a dual-energy mode of 80 kV and 140 kV respectively. The virtual non-enhanced CT (VNCT) images were derived from the data of early interface phase using liver virtual non-contrast software. The diagnose according to VNCT combined dual-phase contrast enhancement CT and dual-phase contrast enhancement CT only were made respectively and compared with χ 2 test. Between the true non-contrast CT and the virtual non-contrast CT, the image quality was compared with Wilcoxon test; The radiation dose of volume CT dose index (CTDIvol) and dose length product(DLP) in a single-phase and total examination, the mean CT HU values of the tumours were compared with t test. Results: The accuracy of VNCT combined dual-phase contrast enhancement CT was higher than that of dual-phase contrast enhancement CT only [93.3% (56/60) vs.78.3% (47/60); χ 2 =5.6, P<0.05]. The detective ability (score) of VNCT was near to that of TNCT and the difference was not obvious (Z=0.00, P>0.05). The radiation dose of volume CT dose index (CTDIvol) and dose length product (DLP) in a single phase and total examination of VNCT [(8.85 ± 1.28) mGy, (196.45 ±21.12) mGy·cm, (17.69±2.35) mGy, (392.90±42.25) mGy · cm] were lower than that of TNCT [(10.20 ± 1.44) mGy,(218.29 ± 29.60) mGy · cm, (30.61 ± 3.27) mGy and (654.86 ± 88.81) mGy ·cm], t=4.21, 3.58, 23.63, 16.12 respectively, P<0.05. The mean CT HU values of tumours on VNCT images was higher than that

  9. Multimodality functional imaging of spontaneous canine tumors using 64CU-ATSM and 18FDG PET/CT and dynamic contrast enhanced perfusion CT

    DEFF Research Database (Denmark)

    Hansen, Anders E; Kristensen, Annemarie T; Law, Ian

    2012-01-01

    To compare the distribution and uptake of the hypoxia tracer (64)Cu-diacetyl-bis(N(4)-methylthiosemicarbazone) ((64)Cu-ATSM) PET/CT, FDG PET/CT and dynamic contrast enhanced perfusion CT (DCE-pCT) in spontaneous canine tumors. In addition (64)Cu-ATSM distribution over time was evaluated.......To compare the distribution and uptake of the hypoxia tracer (64)Cu-diacetyl-bis(N(4)-methylthiosemicarbazone) ((64)Cu-ATSM) PET/CT, FDG PET/CT and dynamic contrast enhanced perfusion CT (DCE-pCT) in spontaneous canine tumors. In addition (64)Cu-ATSM distribution over time was evaluated....

  10. Iohexol for contrast enhancement of bowel in pediatric abdominal CT

    International Nuclear Information System (INIS)

    Smevik, B.; Westvik, J.

    1990-01-01

    Abdominal CT scans from 160 examinations performed on pediatric patients using iohexol 2 percent as contrast medium for bowel enhancement were evaluated retrospectively. When diluted with a beverage of the child's choice, iohexol has a neutral taste and cannot be detected, and 139 out of 142 patients drank the full amount of dilute contrast offered to them. The enhancement of bowel in the area of interest was graded as good (58%), reasonable (23%), or poor (19%). The contrast medium was prepared from leftovers from our angiocardiography studies. We conclude that the use of water-soluble contrast medium in a low concentration is a safe and cost-effective way of facilitating ingesion of sufficient amounts of the medium in oncologic pediatric patients undergoing cytotoxic and/or radiation treatment. (orig.)

  11. Pathomechanism of ring enhancement in intracerebral hematomas on CT

    International Nuclear Information System (INIS)

    Takasugi, Shinsuke; Kageyama, Takefumi; Yamashita, Shigeru; Kusaka, Kazumasa; Ueda, Shin

    1980-01-01

    As a simulation of hypertensive intracerebral hematoma, about 3.5 ml of autologus venous blood were injected into an artificial cavity of a unilateral cerebral hemisphere in dogs. The cavity was made by the insertion and inflation of a balloon canula near the basal ganglia region of the dog. At the acute stage after the injection, the hematoma showed a round-shaped and homogeneous high density. 9 days later, a positive ring enhancement appeared around this high-density area in most of the cases. Subsequently, the hematoma changed into an isodensity with a tendency toward the concentric concentration of the ring enhancement and to the final low-density stage with a spotted enhancement in the center. That is our experimental intracerebral hematoma of the dog showed a pattern of the chronological course of the CT appearance quite similar to that of clinical cases of hypertensive intracerebral hematomas. At the onset of the ring enhancement, many new and immature capillaries were noted in the adjacent tissue of the hematoma, corresponding to the positive enhancement. The new capillaries were gradually shifted to the center of the hematoma; the enhancement also coincided with them. The ultrastructures of these new capillaries were examined electronmicroscopically. There was some resemblance to the capillaries of muscle with many pinocytotic vesicles and shallowed tight junctions. These experimental facts suggest that the enhancement phenomenon occurred in close relationship to the newly produced hypervascularization of the capillaries around the hematoma, which was a phenomenon of the healing process of the lesion. Therefore, the pathomechanism of the enhancement was thought to be involved the pooling of the contrast media in the increased vascular bed as well as a loss of blood brain barrier in these newly produced immature capillaries. (J.P.N.)

  12. Pulmonary CT angiography: optimization of contrast enhancement technique

    International Nuclear Information System (INIS)

    Ma Lianju; Tang Guangjian; Fu Jiazhen

    2012-01-01

    Objective: To derive and evaluate the formula of exactly calculating the contrast dosage used during pulmonary CT angiography (CTPA). Methods: Time density curves in 27 patients who underwent CTPA were collected and analyzed,the formula for calculating contrast dosage during CTPA was derived. 68 patients suspected of pulmonary embolism (PE) clinically but no PE on CTPA were divided randomly into group A, with bolus tracing technique (n=26), and group B, with small dose injection contrast test (SDCT) (n=42). The CT values of the right main pulmonary artery (RMPA), right upper pulmonary vein (RUPV), right posterior basal PA, right lower PV (RLPV) and the aorta were calculated. The total contrast dosage and the hard beam artifact in the SVC were compared between the two groups.Student's t test, Chi-square test and Mann-Whitney U test were used. Results: The ratio of the time from starting injection to enhancement peak of caudal end of SVC and the time to enhancement peak of the main pulmonary trunk was 0.65 ±0.09 (about 2/3), the formula for contrast dosage calculation was derived as (DTs/3 + STs/2) FR ml/s. The CT values of RMPA and RLPA between the two groups [(301 ±117), (329 ± 122) and (283 ±95), (277 ±98) HU respectively] were not significantly different (t=1.060, P=0.292; t=2.056, P=0.044), but the differences of CT values in the paired PA and PV between the two groups (median were 22.5, 58.0 and 170.5, 166.5 HU respectively) were significant (U=292, P=0.001 and U=325, P=0.005), contrast artifact of the SVC (grade 1-3) in group B (n=34, 7, 1 respectively) was significantly less than in group A (n=11, 10, 5 respectively, χ 2 =10.714, P=0.002), the contrast dosage injected in group A was ( 87.6 ± 7.3) ml, and in group B was (40.0 ±5.4) ml (P<0.01). Conclusion: CTPA with SDCT technique is superior to that with conventional bolus tracing technique regarding contrast dosage and contrast artifact in the SVC. (authors)

  13. Prevalence and characteristics of intravertebral enhancement on contrast-enhanced CT scans in cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Rasselet, Benjamin [Medical Imaging Department and Biostatistics Department, Montpellier University Hospital, 191 Avenue du Doyen Gaston Giraud, 34 295 Montpellier Cedex 5 (France); Larbi, Ahmed; Viala, Pierre [Medical Imaging Department, Nimes University Hospital, 4 rue du Professeur Robert Debré, 30029 Nîmes (France); Molinari, Nicolas [Biostatistics Department, Montpellier University Hospital, 191 Avenue du Doyen Gaston Giraud, 34 295 Montpellier Cedex 5 (France); Tetreau, Raphael [Medical Imaging Department, Montpellier Cancer Institute (ICM), 208 Avenue des Apothicaires, 34298 Montpellier Cedex 5 (France); Faruch-Bilfeld, Marie [Medical Imaging Department, Toulouse University Hospital, Place du Docteur Baylac, 31059 Toulouse Cedex 9 (France); Taourel, Patrice [Medical Imaging Department and Biostatistics Department, Montpellier University Hospital, 191 Avenue du Doyen Gaston Giraud, 34 295 Montpellier Cedex 5 (France); Cyteval, Catherine, E-mail: c-cyteval@chu-montpellier.fr [Medical Imaging Department and Biostatistics Department, Montpellier University Hospital, 191 Avenue du Doyen Gaston Giraud, 34 295 Montpellier Cedex 5 (France)

    2017-01-15

    Highlights: • 2.8% of collateral venous circulation seen on CT scan in a cancer population. • 37% of intravertebral enhancement in this population with collateral venous circulation. • 80.8% of intravertebral enhancements are located between C6 and. • 73% of intravertebral enhancements are located ipsilateral to the injection side. -  Abstract: Study design: This was a single center, retrospective observational study. Objective: to investigate—in a cancer population—the prevalence and hallmarks of intravertebral enhancement (IVE) detected on contrast-enhanced CT. Summary of background data: Intravertebral enhancements secondary to iodinated contrast stagnation have been described. Cancer patients have an increased risk of perivertebral venous thrombosis or stenosis secondary to several risk factors (cancer or drug induced hypercoagulability, deterioration of venous flow linked to catheter insertion, prolonged immobilization). In case of a high density lesion identified on CT, the diagnostic choice between metastasis and contrast media within bone marrow vessels may be an issue, especially as oncologic follow-up CT scans are usually performed with contrast medium injection. Methods: 2572 contrast-enhanced body CT scans performed in cancer patients over 3 months in the medical imaging department of a university hospital were retrospectively reviewed. IVE was sought when paravertebral venous collateral circulation was detected and bone metastasis ruled out and classified as linear or nodular. Their locations within vertebra, their relation to the injection side and the predominant collateral venous network side were evaluated. Results: Sixty-seven (2.8%) patients had a collateral paravertebral venous system and among them 21 had IVE (37%). There were 208 IVE locations involving 75 vertebrae. 199 IVE were linear-shaped (95.7%) and 9 nodular-shaped (4.3%). 80.8% were located between C6 and T4. 88.9% were localized in the vertebral body. 73.1% were located

  14. Prevalence and characteristics of intravertebral enhancement on contrast-enhanced CT scans in cancer patients

    International Nuclear Information System (INIS)

    Rasselet, Benjamin; Larbi, Ahmed; Viala, Pierre; Molinari, Nicolas; Tetreau, Raphael; Faruch-Bilfeld, Marie; Taourel, Patrice; Cyteval, Catherine

    2017-01-01

    Highlights: • 2.8% of collateral venous circulation seen on CT scan in a cancer population. • 37% of intravertebral enhancement in this population with collateral venous circulation. • 80.8% of intravertebral enhancements are located between C6 and. • 73% of intravertebral enhancements are located ipsilateral to the injection side. -  Abstract: Study design: This was a single center, retrospective observational study. Objective: to investigate—in a cancer population—the prevalence and hallmarks of intravertebral enhancement (IVE) detected on contrast-enhanced CT. Summary of background data: Intravertebral enhancements secondary to iodinated contrast stagnation have been described. Cancer patients have an increased risk of perivertebral venous thrombosis or stenosis secondary to several risk factors (cancer or drug induced hypercoagulability, deterioration of venous flow linked to catheter insertion, prolonged immobilization). In case of a high density lesion identified on CT, the diagnostic choice between metastasis and contrast media within bone marrow vessels may be an issue, especially as oncologic follow-up CT scans are usually performed with contrast medium injection. Methods: 2572 contrast-enhanced body CT scans performed in cancer patients over 3 months in the medical imaging department of a university hospital were retrospectively reviewed. IVE was sought when paravertebral venous collateral circulation was detected and bone metastasis ruled out and classified as linear or nodular. Their locations within vertebra, their relation to the injection side and the predominant collateral venous network side were evaluated. Results: Sixty-seven (2.8%) patients had a collateral paravertebral venous system and among them 21 had IVE (37%). There were 208 IVE locations involving 75 vertebrae. 199 IVE were linear-shaped (95.7%) and 9 nodular-shaped (4.3%). 80.8% were located between C6 and T4. 88.9% were localized in the vertebral body. 73.1% were located

  15. Budd-Chiari syndrome: dynamic enhancement findings with multi-slice helical CT and CT angiography analysis

    International Nuclear Information System (INIS)

    Meng Xiaochun; Shan Hong; Zhu Kangshun; Xu Chuan; Zhang Jiansheng; Liu Lingyun; Ye Binbin

    2005-01-01

    Objective: To investigate the dynamic enhancement regulations of liver and their mechanism in Budd-Chiari syndrome (BCS) by using multi-slice CT and evaluate the value of CT angiography in the diagnosis of BCS. Methods: 28 cases with BCS confirmed by digital subtraction angiography (DSA) were retrospectively analyzed. All patients underwent dynamic enhancement examinations with multi-slice CT within 1 week before DSA. The relevant vessels were reconstructed respectively with MIP, VR and MPR. Compared with the results of DSA, we analyzed the dynamic enhancement regulations of liver in BCS, estimated the value of dynamic enhancement CT exams and CTA techniques in judging the obstruction level and showing collateral vessels. Results: Of all 28 cases, CT correctly showed the obstruction level in 26 cases, and 2 had incorrect results which proved to be membranous obstruction of the inferior vena cava superior to diaphragm. In 22 cases with hepatic vein obstructions, hepatic parenchyma displayed typical patchy enhancement in 19, atypical patchy enhancement in 3.8 cases among these showed benign nodules. Simultaneously, CT showed stenosis and rigidity of portal vein branches in 20, enlargement of hepatic artery in 14, hepatic collateral vessels in 20 out of 22 cases. In 6 cases with simple obstruction of inferior vena cava, hepatic changes were not found. Collateral circulations in or out of liver corresponded to the obstruction level. Conclusion: Dynamic enhancement examinations with multi-slice CT can correctly reflect the hepatic hemodynamic changes. Transverse images, combined with CTA, can explicitly display the obstruction level of vascular lesions and collateral circulations in BCS. (authors)

  16. Assessment of pulmonary ventilation patterns by nonradioactive Xe enhanced CT

    International Nuclear Information System (INIS)

    Shiraishi, Tomokuni; Mizuno, Masayoshi; Harima, Yoko; Kobayashi, Akitomo; Hasegawa, Takeo

    1984-01-01

    To assess the patterns of regional pulmonary ventilation in conjunction with pulmonary blood flow, pulmonary Xe enhanced CT was performed in 26 patients with interstitial disorders including 3 with chest irradiation and 23 with old myocardial infarction and in 2 control patients. Washout time was short and its patterns were not influenced by an increased or decreased blood flow in the control group. In the group with chest irradiation, a decreased blood flow and slight disturbance were seen in the affected lung, while an increased blood flow and a slightly increased resistance of the pulmonary periphery were suspected in the opposite lung. Furthermore, a prolonged washout and relative reduction of the washout seemed to be reflective of the interstitial degeneration and decreased blood flow, respectively. In the group with old myocardial infarction, the prolongation of washout became marked because of a decreased blood flow caused by venous congestion. (Namekawa, K.)

  17. 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.

  18. Adaptive radiotherapy based on contrast enhanced cone beam CT imaging

    International Nuclear Information System (INIS)

    Soevik, Aaste; Skogmo, Hege K.; Roedal, Jan; Lervaag, Christoffer; Eilertsen, Karsten; Malinen, Eirik

    2010-01-01

    Cone beam CT (CBCT) imaging has become an integral part of radiation therapy, with images typically used for offline or online patient setup corrections based on bony anatomy co-registration. Ideally, the co-registration should be based on tumor localization. However, soft tissue contrast in CBCT images may be limited. In the present work, contrast enhanced CBCT (CECBCT) images were used for tumor visualization and treatment adaptation. Material and methods. A spontaneous canine maxillary tumor was subjected to repeated cone beam CT imaging during fractionated radiotherapy (10 fractions in total). At five of the treatment fractions, CECBCT images, employing an iodinated contrast agent, were acquired, as well as pre-contrast CBCT images. The tumor was clearly visible in post-contrast minus pre-contrast subtraction images, and these contrast images were used to delineate gross tumor volumes. IMRT dose plans were subsequently generated. Four different strategies were explored: 1) fully adapted planning based on each CECBCT image series, 2) planning based on images acquired at the first treatment fraction and patient repositioning following bony anatomy co-registration, 3) as for 2), but with patient repositioning based on co-registering contrast images, and 4) a strategy with no patient repositioning or treatment adaptation. The equivalent uniform dose (EUD) and tumor control probability (TCP) calculations to estimate treatment outcome for each strategy. Results. Similar translation vectors were found when bony anatomy and contrast enhancement co-registration were compared. Strategy 1 gave EUDs closest to the prescription dose and the highest TCP. Strategies 2 and 3 gave EUDs and TCPs close to that of strategy 1, with strategy 3 being slightly better than strategy 2. Even greater benefits from strategies 1 and 3 are expected with increasing tumor movement or deformation during treatment. The non-adaptive strategy 4 was clearly inferior to all three adaptive strategies

  19. Detection of breast abnormalities on enhanced chest CT: Correlation with breast composition on mammography

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Eun Mi; Kang, Hee; Shin, Young Gyung; Yun, Jong Hyouk; Oh, Kyung Seung [Dept. of Radiology, Kosin University Gospel Hospital, Kosin University College of Medicine, Busan (Korea, Republic of)

    2017-02-15

    To investigate the capability of enhanced chest computed tomography (CT) for detecting breast abnormalities and to assess the influence of breast composition on this detectability. From 2000 to 2013, 75 patients who underwent mammography, breast sonography, and enhanced chest CT within one month and had abnormalities on sonography were included. Detection rate of breast abnormality on enhanced chest CT was compared among 4 types of breast composition by the Breast Imaging Reporting and Data System. Contribution of breast composition, size and enhancement of target lesions to detectability of enhanced chest CT was assessed using logistic regression and chi-square test. Of the 75 target lesions, 34 (45.3%) were detected on enhanced chest CT, corresponding with those on breast sonography; there were no significantly different detection rates among the 4 types of breast composition (p = 0.078). Breast composition [odds ratio (OR) = 1.07, p = 0.206] and enhancement (OR = 21.49, p = 0.998) had no significant effect, but size (OR = 1.23, p = 0.004) was a significant contributing factor influencing the detectability of enhanced chest CT for breast lesions. About half of the cases (45.3%) demonstrated breast lesions on chest CT corresponding with target lesions on sonography. Breast composition defined on mammography did not affect the detectability of enhanced chest CT for breast lesions.

  20. Addison's disease due to adrenal tuberculosis: Contrast-enhanced CT features and clinical duration correlation

    International Nuclear Information System (INIS)

    Guo Yingkun; Yang Zhigang; Li Yuan; Ma Ensen; Deng Yuping; Min Pengqiu; Yin Longlin; Hu Jian; Zhang Xiaochun; Chen Tianwu

    2007-01-01

    Purpose: To describe CT morphology of untreated adrenal tuberculosis during the different stages of the natural history of the disease and to evaluate the diagnostic implications of CT features. Materials and methods: We retrospectively evaluated CT features in 42 patients with documented adrenal tuberculosis for the location, size, morphology, and enhancement patterns shown on CT images. The clinical duration were correlated with the CT features. Results: Of the 42 patients with untreated adrenal tuberculosis, bilaterally enlarged adrenal glands were revealed in 38 cases (91%), unilaterally enlarged in 3 cases (7%), and normal size in 1 case (2%). Of the 41 cases (98%) with enlargement, mass-like enlargement was seen in 20 cases (49%) and enlargement with preserved contours in 21 cases (51%). Peripheral rim enhancement presented in 22 cases (52%) on contrast-enhanced CT. Non-enhanced CT scan revealed calcification in 21 cases (50%). As the duration of Addison's disease increased, the presence of calcification and contour preservation increased concomitantly (p < 0.001), whereas peripheral rim enhancement and mass-like enlargement decreased concomitantly on CT images (p < 0.001). Conclusion: CT may be helpful in diagnosing adrenal tuberculosis when clinically suspected, and CT features are correlated to the clinical duration of Addison's disease

  1. The value of contrast-enhanced CT scan in prediction of development of contusional hemorrhage

    International Nuclear Information System (INIS)

    Yokoyama, Kazuhiro; Kyoi, Kikuo; Sakaki, Toshisuke; Kinugawa, Kazuhiko; Morimoto, Tetsuya

    1983-01-01

    It is often experienced that even if there are no significant findings on the initial plain CT scan in the patient with cerebral contusion, the patient has thereafter a serious clinical course and requires emergency operation for so-called contusional hemorrhage. In order to predict of the development of contusional hemorrhage we performed contrast-enhanced CT scan at the time of patient's arrival within 12 hours after injury, if there was cerebral contusion on the initial plain CT scan, and repeated plain CT scan 24 hours after the contrast-enhanced CT scan. If enhancement was demonstrated on the contrastenhanced CT scan, we predicted the development of contusional hemorrhage and if not demonstrated, we predicted no more development of contusional hemorrhage and then we studied the correlation between the prediction and the plain CT 24 hours after the contrast-enhanced CT scan. The results were as follows: 1) The prediction was correct in 13 cases out of 16 cases in which the development of contusional hemorrhage was observed. In 18 cases where no development of contusional hemorrhage was observed, the prediction was correct without exception. 2) Most of the cases in which enhancement was demonstrated were ones examined not before 3 hours after injury. 3) The extent of enhancement shown on contrastenhanced CT scan was well consistent with that of contusional hemorrhage on the plain CT scan 24 hours after the contrast-enhanced CT scan. From these results, the contrast-enhanced CT scan in acute stage of head injury was considered to by very useful in prediction of the development of contusional hemorrhage. (author)

  2. Investigations into the use of SNOMED CT to enhance an OpenMRS health information system

    CSIR Research Space (South Africa)

    Halland, K

    2011-07-01

    Full Text Available In this paper, the authors discuss the advantages of using formal medical ontologies to enhance health information systems. In particular, they consider the suitability of the medical ontology Snomed CT for enhancing a health information system...

  3. Utility of bolus dynamic CT for the detection of hypervascular malignant hepatic tumors. Mainly referring to the comparison with delayed phase contrast-enhanced CT

    International Nuclear Information System (INIS)

    Matsuda, Hiromichi; Abe, Kimihiko; Freeny, P.C.

    1996-01-01

    In order to analyze the usefulness of dynamic contrast-enhanced CT, 84 patients who had hepatocellular carcinoma or suspected hypervascular metastases were studied with conventional incremental dynamic CT (CID-CT) or double helical CT (DH-CT). Delayed phase contrast-enhanced CT studies were consecutively performed in all patients. Thirty-six of 84 patients had malignant hepatic neoplasms; six had hepatocellular carcinoma and 30 had metastatic tumors. At first, the detectability of hepatic lesions was evaluated with bolus dynamic CT and delayed phase CT. Dynamic CT has detected more lesions than delayed CT. Some hepatic lesions described as isodensity were missed on CID-CT. Therefore, delayed phase CT cannot be eliminated when CID-CT is performed. Secondly, hepatic lesion detectability with CID-CT was compared with that of DH-CT. DH-CT did not miss the hepatic lesions picked up by delayed phase CT and was expected to provide excellent detectability of hypervascular hepatic neoplasms. In addition, first helical CT showed most hepatic lesions as areas of obvious hyperdensity, while CID-CT did not show their correct vascularities. So-called hypervascular hepatic tumors, however, were not always hypervascular and were demonstrated as areas of iso-hypodensity even on initial helical scanning. Second helical CT was useful to detect these so-called hypervascular, but actually hypovascular lesions. In conclusion, dynamic CT was helpful in detecting hypervascular hepatic malignant neoplasms, and DH-CT was more accurate than-CID-CT for the detection of hepatic lesions and the evaluation of vascular lesion. (author)

  4. {sup 18}F-FDG PET/CT and contrast-enhanced CT findings of pulmonary cryptococcosis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Si-yun, E-mail: wang_shuxia@outlook.com [Department of PET Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Chen, Gang, E-mail: cgggh@outlook.com [Department of Thoracic Surgery, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Luo, Dong-lan, E-mail: 695532870@qq.com [Department of Pathology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Shao, Dan, E-mail: shaodan501@outlook.com [Department of PET Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Liu, En-tao, E-mail: GDGH2015@gmail.com [Department of PET Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Sun, Taotao, E-mail: sunmoodsdaisy@bjmu.edu.cn [Department of PET Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Wang, Shu-Xia, E-mail: wsyggh@outlook.com [Department of PET Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China)

    2017-04-15

    Purpose: Pulmonary cryptococcosis is an uncommon cause of pulmonary nodules in non-AIDS patients. This study reports the {sup 18}F-fluorodeoxyglucose-positron emission tomography ({sup 18}F-FDG PET/CT) and contrast-enhanced CT (CE-CT) findings of 42 patients with pulmonary cryptococcosis. Materials and methods: A retrospective review of the {sup 18}F-FDG PET/CT and CE-CT findings of 42 patients with histologically proven pulmonary cryptococcosis was conducted. All patients underwent PET/CT and CE-CT in the same session. The CT diagnosis was based on the location, morphological features, and enhancement of lesions. The PET/CT findings were recorded, and clinical data and surgical and histopathological findings were collected. Results: The results of the PET scans revealed that 37 (88%) of 42 patients showed higher FDG uptake, and 5 (12%) patients demonstrated lower FDG uptake than the mediastinal blood pool. The maximum standardized uptake value (SUV) of pulmonary cryptococcosis ranged from 1.4 to 13.0 (average: 5.7 ± 3.3, median 4.9). A single nodular pattern was the most prevalent pattern observed and was found in 29 (69%) patients. This pattern was followed by scattered nodular (n = 4, 10%), clustered nodular (n = 3, 7%), mass-like (n = 3, 7%), and bronchopneumonic (n = 3, 7%) patterns. The most frequent pattern of immunocompetent patients was the single nodular pattern (29 of 33, 88%). Immunocompromised patients most frequently pattern exhibited mass-like (3 of 9, 33%) and bronchopneumonic (3 of 9, 33%) patterns. Conclusion: Pulmonary cryptococcosis most commonly appears as single nodules in immunocompetent patients. Mass-like and bronchopneumonic patterns were common in immunocompromised patients. In 88% of patients, lung lesions showed high FDG uptake, thus mimicking a possible malignant condition.

  5. Enhanced transbuccal salmon calcitonin (sCT) delivery: effect of chemical enhancers and electrical assistance on in vitro sCT buccal permeation.

    Science.gov (United States)

    Oh, Dong-Ho; Chun, Kyeung-Hwa; Jeon, Sang-Ok; Kang, Jeong-Won; Lee, Sangkil

    2011-10-01

    This study investigates the combined effect of absorption enhancers and electrical assistance on transbuccal salmon calcitonin (sCT) delivery, using fresh swine buccal tissue. We placed 200 IU (40 μg/mL) of each sCT formulation--containing various concentrations of ethanol, N-acetyl-L-cysteine (NAC), and sodium deoxyglycocholate (SDGC)--onto the donor part of a Franz diffusion cell. Then, 0.5 mA/cm(2) of fixed anodal current was applied alone or combined with chemical enhancers. The amount of permeated sCT was analyzed using an ELISA kit, and biophysical changes of the buccal mucosa were investigated using FT-IR spectroscopy, and hematoxylin-eosin staining methods were used to evaluate histological alteration of the buccal tissues. The flux (J(s)) of sCT increased with the addition of absorption enhancer groups, but it was significantly enhanced by the application of anodal iontophoresis (ITP). FT-IR study revealed that all groups caused an increase in lipid fluidity but only the groups containing SDGC showed statistically significant difference. Although the histological data of SDGC groups showed a possibility for tissue damage, the present enhancing methods appear to be safe. In conclusion, the combination of absorption enhancers and electrical assistance is a potential strategy for the enhancement of transbuccal sCT delivery. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Enhancement pattern of small hepatic hemangioma: findings on multiphase spiral CT and dynamic MRI

    International Nuclear Information System (INIS)

    Choi, Byung In; Lee, Seung Koo; Kim, Myeong Jin; Chung, Jae Joon; Yoo, Hyung Sik; Lee, Jong Tae

    1999-01-01

    To compare the enhancement characteristics of small hemangiomas seen on multiphase spiral CT and dynamic MR imaging. Thirteen patients with 20 hepatic hemangiomas less than 25mm in diameter underwent both multiphase spiral CT and dynamic MR imaging. All lesions were assigned to one of three classified into 3 categories according to the enhancement pattern seen on multiphase spiral CT : typical delayed pooling, atypical early enhancement, or continuous low attenuation. The enhancement patterns seen on spiral CT and on dynamic MRI were correlated. On CT scans, ten lesions (50%) showed delayed pooling. Six (30%) showed early arterial enhancement and four (20%) showed continuous low attenuation. On delayed-phase MRI, all lesions showed delayed high signal intensity compared to adjacent liver parenchyma. Four of six lesions with early enhancement on CT showed peripheral globular enhancement on early arterial-phase MRI. On multiphase spiral CT scans, small hemangiomas can show variable atypical enhancement features. In this situation, contrast-enhanced dynamic MRI is helpful for the diagnosis of hemangiomas

  7. Xenon-enhanced CT using subtraction CT: Basic and preliminary clinical studies for comparison of its efficacy with that of dual-energy CT and ventilation SPECT/CT to assess regional ventilation and pulmonary functional loss in smokers

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.jp [Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe (Japan); Yoshikawa, Takeshi [Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe (Japan); Takenaka, Daisuke [Department of Radiology, Hyogo Cancer Center, Akashi (Japan); Fujisawa, Yasuko; Sugihara, Naoki [Toshiba Medical Systems Corporation, Otawara (Japan); Kishida, Yuji; Seki, Shinichiro; Koyama, Hisanobu; Sugimura, Kazuro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine (Japan)

    2017-01-15

    Purpose: To prospectively and directly compare the capability for assessments of regional ventilation and pulmonary functional loss in smokers of xenon-ventilation CT obtained with the dual-energy CT (DE-CT) and subtraction CT (Sub-CT) Materials and methods: Twenty-three consecutive smokers (15 men and 8 women, mean age: 69.7 ± 8.7 years) underwent prospective unenhanced and xenon-enhanced CTs, the latter by Sub-CT and DE-CT methods, ventilation SPECT and pulmonary function tests. Sub-CT was generated from unenhanced and xenon-enhanced CT, and all co-registered SPECT/CT data were produced from SPECT and unenhanced CT data. For each method, regional ventilation was assessed by using a 11-point scoring system on a per-lobe basis. To determine the functional lung volume by each method, it was also calculated for individual sublets with a previously reported method. To determine inter-observer agreement for each method, ventilation defect assessment was evaluated by using the χ2 test with weighted kappa statistics. For evaluation of the efficacy of each method for pulmonary functional loss assessment, functional lung volume was correlated with%FEV{sub 1}. Results: Each inter-observer agreement was rated as substantial (Sub-CT: κ = 0.69, p < 0.0001; DE-CT: κ = 0.64, p < 0.0001; SPECT/CT: κ = 0.64, p < 0.0001). Functional lung volume for each method showed significant to good correlation with%FEV{sub 1} (Sub-CT: r = 0.72, p = 0.0001; DE-CT: r = 0.74, p < 0.0001; SPECT/CT: r = 0.66, p = 0.0006). Conclusion: Xenon-enhanced CT obtained by Sub-CT can be considered at least as efficacious as that obtained by DE-CT and SPECT/CT for assessment of ventilation abnormality and pulmonary functional loss in smokers.

  8. The effect of iodine uptake on radiation dose absorbed by patient tissues in contrast enhanced CT imaging. Implications for CT dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Perisinakis, Kostas; Damilakis, John [University of Crete, Department of Medical Physics, Medical School, Heraklion, Crete (Greece); University Hospital of Heraklion, Department of Medical Physics, Heraklion, Crete (Greece); Tzedakis, Antonis; Papadakis, Antonios E. [University Hospital of Heraklion, Department of Medical Physics, Heraklion, Crete (Greece); Spanakis, Kostas [University Hospital of Heraklion, Department of Radiology, Heraklion, Crete (Greece); Hatzidakis, Adam [University Hospital of Heraklion, Department of Radiology, Heraklion, Crete (Greece); University of Crete, Department of Radiology, Medical School, Heraklion, Crete (Greece)

    2018-01-15

    To investigate the effect of iodine uptake on tissue/organ absorbed doses from CT exposure and its implications in CT dosimetry. The contrast-induced CT number increase of several radiosensitive tissues was retrospectively determined in 120 CT examinations involving both non-enhanced and contrast-enhanced CT imaging. CT images of a phantom containing aqueous solutions of varying iodine concentration were obtained. Plots of the CT number increase against iodine concentration were produced. The clinically occurring iodine tissue uptake was quantified by attributing recorded CT number increase to a certain concentration of aqueous iodine solution. Clinically occurring iodine uptake was represented in mathematical anthropomorphic phantoms. Standard 120 kV CT exposures were simulated using Monte Carlo methods and resulting organ doses were derived for non-enhanced and iodine contrast-enhanced CT imaging. The mean iodine uptake range during contrast-enhanced CT imaging was found to be 0.02-0.46% w/w for the investigated tissues, while the maximum value recorded was 0.82% w/w. For the same CT exposure, iodinated tissues were found to receive higher radiation dose than non-iodinated tissues, with dose increase exceeding 100% for tissues with high iodine uptake. Administration of iodinated contrast medium considerably increases radiation dose to tissues from CT exposure. (orig.)

  9. CTA-enhanced perfusion CT: an original method to perform ultra-low-dose CTA-enhanced perfusion CT

    Energy Technology Data Exchange (ETDEWEB)

    Tong, Elizabeth; Wintermark, Max [University of Virginia, Department of Radiology, Neuroradiology Division, Charlottesville, VA (United States)

    2014-11-15

    Utilizing CT angiography enhances image quality in PCT, thereby permitting acquisition at ultra-low dose. Dynamic CT acquisitions were obtained at 80 kVp with decreasing tube current-time product [milliamperes x seconds (mAs)] in patients suspected of ischemic stroke, with concurrent CTA of the cervical and intracranial arteries. By utilizing fast Fourier transformation, high spatial frequencies of CTA were combined with low spatial frequencies of PCT to create a virtual PCT dataset. The real and virtual PCT datasets with decreasing mAs were compared by assessing contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR), and noise and PCT values and by visual inspection of PCT parametric maps. Virtual PCT attained CNR and SNR three- to sevenfold superior to real PCT and noise reduction by a factor of 4-6 (p < 0.05). At 20 mAs, virtual PCT achieved diagnostic parametric maps, while the quality of real PCT maps was inadequate. At 10 mAs, both real and virtual PCT maps were nondiagnostic. Virtual PCT (but not real PCT) maps regained diagnostic quality at 10 mAs by applying 40 % adaptive statistical iterative reconstruction (ASIR) and improved further with 80 % ASIR. Our new method of creating virtual PCT by combining ultra-low-dose PCT with CTA information yields diagnostic perfusion parametric maps from PCT acquired at 20 or 10 mAs with 80 % ASIR. Effective dose is approximately 0.20 mSv, equivalent to two chest radiographs. (orig.)

  10. Impact of Different CT Slice Thickness on Clinical Target Volume for 3D Conformal Radiation Therapy

    International Nuclear Information System (INIS)

    Prabhakar, Ramachandran; Ganesh, Tharmar; Rath, Goura K.; Julka, Pramod K.; Sridhar, Pappiah S.; Joshi, Rakesh C.; Thulkar, Sanjay

    2009-01-01

    The purpose of this study was to present the variation of clinical target volume (CTV) with different computed tomography (CT) slice thicknesses and the impact of CT slice thickness on 3-dimensional (3D) conformal radiotherapy treatment planning. Fifty patients with brain tumors were selected and CT scans with 2.5-, 5-, and 10-mm slice thicknesses were performed with non-ionic contrast enhancement. The patients were selected with tumor volume ranging from 2.54 cc to 222 cc. Three-dimensional treatment planning was performed for all three CT datasets. The target coverage and the isocenter shift between the treatment plans for different slice thickness were correlated with the tumor volume. An important observation from our study revealed that for volume 25 cc, the target underdosage was less than 6.7% for 5-mm slice thickness and 8% for 10-mm slice thickness. For 3D conformal radiotherapy treatment planning (3DCRT), a CT slice thickness of 2.5 mm is optimum for tumor volume 25 cc

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

    Science.gov (United States)

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

    2014-08-01

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

  12. Diagnostic value of contrast-enhanced dynamic CT in predicting the malignancy of solitary pulmonary nodules

    International Nuclear Information System (INIS)

    Goo, Hyun Woo; Song, Koun Sik; Lee, Eun Hye; Kim, Ji Hoon; Lee, Jin Seong; Lim, Tae Hwan

    1997-01-01

    To determine whether the maximal enhancement time in dynamic CT is different between benign and malignant solitary pulmonary nodules (SPN)s, and to evaluate the value of densitometry on dynamic CT in predicting the malignancy of SPN. Fifty-six patients with SPN of less than 4cm in diameter as seen on chest radiograph and SPN without benign pattern of calcification or fat, as seen on pre-enhance-ment spiral CT scans were included in this study. SPN with small cavitation sufficient to measure CT density, were also included. Thirty-four SPNs were diagnosed pathologically or radiologically as 20 malignant nodules and 14 benign nodules. Dynamic CT was performed by two techniques after injection of 50ml of nonionic contrast media at the rate of 2ml/sec. In 28 patients, incremental dynamic CT was performed before and of 15 seconds, 1 minute, 2 minutes, 3 minutes, and 4 minutes after injection of contrast media during shallow respiration. In 28 patients, double spiral CT was performed 2 minutes and 3 minutes after injection of contrast media during single breath hold. CT readings were taken at the central portion of SPNs, with a circular region of interest. The degree and time of maximal enhancement were recorded. In dynamic CT the maximal enhancement time of SPNs was not significantly different between malignant (2.73±1.27 minute) and benign nodules (2.56±1.24 minute). The enhancement of malignant nodules was significantly greater (21.42±12.17 HU) than of benign nodules (5.15±5.25 HU) (p<.0001). In dynamic CT of SPNs, there is no difference in maximal enhancement time between benign and malignant nodules;enhancement of the latter is significantly greater than that of the former. Maximal enhancement greater than 15 HU can be a good predictor of malignancy of SPNs

  13. Triphasic contrast enhanced CT simulation with bolus tracking for pancreas SBRT target delineation.

    Science.gov (United States)

    Godfrey, Devon J; Patel, Bhavik N; Adamson, Justus D; Subashi, Ergys; Salama, Joseph K; Palta, Manisha

    Bolus-tracked multiphasic contrast computed tomography (CT) is often used in diagnostic radiology to enhance the visibility of pancreas tumors, but is uncommon in radiation therapy pancreas CT simulation, and its impact on gross tumor volume (GTV) delineation is unknown. This study evaluates the lesion conspicuity and consistency of pancreas stereotactic body radiation therapy (SBRT) GTVs contoured in the different contrast phases of triphasic CT simulation scans. Triphasic, bolus-tracked planning CT simulation scans of 10 consecutive pancreas SBRT patients were acquired, yielding images of the pancreas during the late arterial (LA), portal venous (PV), and either the early arterial or delayed phase. GTVs were contoured on each phase by a gastrointestinal-specialized radiation oncologist and reviewed by a fellowship-trained abdominal radiologist who specializes in pancreatic imaging. The volumes of the registered GTVs, their overlap ratio, and the 3-dimensional margin expansions necessary for each GTV to fully encompass GTVs from the other phases were calculated. The contrast difference between tumor and normal pancreas was measured, and 2 radiation oncologists rank-ordered the phases according to their value for the lesion-contouring task. Tumor-to-pancreas enhancement was on average much larger for the LA and PV than the delayed phase or early arterial phases; the LA and PV phases were also consistently preferred by the radiation oncologists. Enhancement differences among the phases resulted in highly variable GTV volumes with no observed trends. Overlap ratios ranged from 18% to 75% across all 3 phases, improving to 43% to 91% when considering only the preferred LA and PV phases. GTV expansions necessary to encompass all GTVs ranged from 0.3 to 1.8 cm for all 3 phases, improving slightly to 0.1 to 1.4 cm when considering just the LA and PV phases. For pancreas SBRT, we recommend combining the GTVs from a multiphasic CT simulation with bolus-tracking, including

  14. Comparison of AMI-25 enhanced MRI and helical dynamic CT in the detection of hepatic lesions

    International Nuclear Information System (INIS)

    Saitou, Kazuhiro; Matsuda, Hiromichi; Fukushima, Hiroaki; Kanzaki, Hiroshi; Hirose, Takashi; Karizaki, Dai; Abe, Kimihiko; Amino, Saburou

    1994-01-01

    We performed AMI-25 enhanced MRI and helical dynamic CT in 12 cases of hepatic lesions. Nine of these were hepatocellular carcinomas. Two cases were metastatic liver tumors (the primary lesion was gastric in one and the other was gallbladder cancer). One case was suspected to be adenomatous hyperplasia. Thirty-two lesions were detected in T2-weighted SE images before AMI-25 administration, while 46 lesions were detected in AMI-25 enhanced MRI images. In particular, AMI-25 enhanced MRI was superior to plain MRI in lesions less than 10 mm in size. A total of 48 lesions were detected in helical dynamic CT. Although AMI-25 enhanced MRI almost equaled helical dynamic CT in the detection of liver tumors, helical dynamic CT was slightly superior to AMI-25 enhanced MRI in the detection of subphrenic lesions. It was possible to know the hemodynamics in each hepatic lesion by helical dynamic CT. AMI-25 enhanced MRI was useful to know the inclusion of reticuloendothelial system, and that yielded different diagnoses in adenomatous hyperplasia and well differentiated hepatocellular carcinoma. Helical dynamic CT was useful for qualitative diagnosis. Both AMI-25 enhanced MRI and helical dynamic CT contributed to the detection of liver tumor and qualitative diagnosis. (author)

  15. Assessment of contrast enhanced respiration managed cone-beam CT for image guided radiotherapy of intrahepatic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Nikolaj K. G., E-mail: nkyj@regionsjaelland.dk [Physics and Engineering, London Regional Cancer Program, London, Ontario N6A3K7 (Canada); Stewart, Errol [Radiology, St. Joseph' s Health Care, London, Ontario N6A 4V2 (Canada); Imaging Research Lab, Robarts Research Institute, London, Ontario N6A 5B7 (Canada); Imaging Program, Lawson Health Research Institute, London, Ontario N6C 2R5 (Canada); Lock, Michael; Fisher, Barbara [Radiation Oncology, London Regional Cancer Program, London, Ontario N6A3K7 (Canada); Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6 (Canada); Kozak, Roman [Radiology, St. Joseph' s Health Care, London, Ontario N6A 4V2 (Canada); Chen, Jeff [Physics and Engineering, London Regional Cancer Program, London, Ontario N6A3K7 (Canada); Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6 (Canada); Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1 (Canada); Lee, Ting-Yim [Radiology, St. Joseph' s Health Care, London, Ontario N6A 4V2 (Canada); Imaging Research Lab, Robarts Research Institute, London, Ontario N6A 5B7 (Canada); Imaging Program, Lawson Health Research Institute, London, Ontario N6C 2R5 (Canada); Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6 (Canada); Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1 (Canada); Wong, Eugene [Physics and Engineering, London Regional Cancer Program, London, Ontario N6A3K7 (Canada); Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6 (Canada); Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1 (Canada); Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7 (Canada)

    2014-05-15

    Purpose: Contrast enhancement and respiration management are widely used during image acquisition for radiotherapy treatment planning of liver tumors along with respiration management at the treatment unit. However, neither respiration management nor intravenous contrast is commonly used during cone-beam CT (CBCT) image acquisition for alignment prior to radiotherapy. In this study, the authors investigate the potential gains of injecting an iodinated contrast agent in combination with respiration management during CBCT acquisition for liver tumor radiotherapy. Methods: Five rabbits with implanted liver tumors were subjected to CBCT with and without motion management and contrast injection. The acquired CBCT images were registered to the planning CT to determine alignment accuracy and dosimetric impact. The authors developed a simulation tool for simulating contrast-enhanced CBCT images from dynamic contrast enhanced CT imaging (DCE-CT) to determine optimal contrast injection protocols. The tool was validated against contrast-enhanced CBCT of the rabbit subjects and was used for five human patients diagnosed with hepatocellular carcinoma. Results: In the rabbit experiment, when neither motion management nor contrast was used, tumor centroid misalignment between planning image and CBCT was 9.2 mm. This was reduced to 2.8 mm when both techniques were employed. Tumors were not visualized in clinical CBCT images of human subjects. Simulated contrast-enhanced CBCT was found to improve tumor contrast in all subjects. Different patients were found to require different contrast injections to maximize tumor contrast. Conclusions: Based on the authors’ animal study, respiration managed contrast enhanced CBCT improves IGRT significantly. Contrast enhanced CBCT benefits from patient specific tracer kinetics determined from DCE-CT.

  16. Assessment of contrast enhanced respiration managed cone-beam CT for image guided radiotherapy of intrahepatic tumors

    International Nuclear Information System (INIS)

    Jensen, Nikolaj K. G.; Stewart, Errol; Lock, Michael; Fisher, Barbara; Kozak, Roman; Chen, Jeff; Lee, Ting-Yim; Wong, Eugene

    2014-01-01

    Purpose: Contrast enhancement and respiration management are widely used during image acquisition for radiotherapy treatment planning of liver tumors along with respiration management at the treatment unit. However, neither respiration management nor intravenous contrast is commonly used during cone-beam CT (CBCT) image acquisition for alignment prior to radiotherapy. In this study, the authors investigate the potential gains of injecting an iodinated contrast agent in combination with respiration management during CBCT acquisition for liver tumor radiotherapy. Methods: Five rabbits with implanted liver tumors were subjected to CBCT with and without motion management and contrast injection. The acquired CBCT images were registered to the planning CT to determine alignment accuracy and dosimetric impact. The authors developed a simulation tool for simulating contrast-enhanced CBCT images from dynamic contrast enhanced CT imaging (DCE-CT) to determine optimal contrast injection protocols. The tool was validated against contrast-enhanced CBCT of the rabbit subjects and was used for five human patients diagnosed with hepatocellular carcinoma. Results: In the rabbit experiment, when neither motion management nor contrast was used, tumor centroid misalignment between planning image and CBCT was 9.2 mm. This was reduced to 2.8 mm when both techniques were employed. Tumors were not visualized in clinical CBCT images of human subjects. Simulated contrast-enhanced CBCT was found to improve tumor contrast in all subjects. Different patients were found to require different contrast injections to maximize tumor contrast. Conclusions: Based on the authors’ animal study, respiration managed contrast enhanced CBCT improves IGRT significantly. Contrast enhanced CBCT benefits from patient specific tracer kinetics determined from DCE-CT

  17. Evaluation of delayed contrast-enhanced CT scan in diagnosing hilar cholangiocarcinoma

    International Nuclear Information System (INIS)

    Li Jianding; Liang Chenyang; Zhang Hua; Zhang Yuezhen; Li Rui

    2001-01-01

    Objective: To assess the diagnostic value of delayed CT contrast enhancement patterns in hilar cholangiocarcinoma based on two-phased dynamic incremental CT scanning. Methods: Fifty-two patients with suspected hilar tumor and bile duct obstruction underwent spiral CT scan. The scan time for one revolution of the X-ray tube was 1 second. To elucidate the delay time for optimal imaging, all proved cholangiocarcinoma with delayed (6, 8, 10, 15, 20, 30 minutes) post-equilibrium-phase contrast-enhanced CT scans were acquired with unenhanced, dynamic contrast-enhanced, and delayed images. Degree of delayed enhancement was compared with that of surrounding liver parenchyma. Results: (1) 8-15 minutes after IV injection of contrast material was the delay time for optimal imaging. (2) Of 29 cholangiocarcinomas, the early CT showed hypo-attenuating (lower than that of liver parenchyma) in 23 tumors, iso-attenuating (equal to that of the liver) in 4 tumors, and hyper-attenuating (higher than that of liver) in 2 tumors. The delayed CT scan showed iso-attenuating in 8 tumors, hyper-attenuating in 21 tumors, and no hypo-attenuating. Most of delay imaging of hilar cholangiocarcinoma may appear hyper-attenuating (U = -4.3073, P 2 = 9.09, P < 0.01). Conclusion: When assessing hilar tumor, delayed CT contrast enhancement patterns based on two-phase dynamic incremental CT scans is useful in the detection and characterization of hilar cholangiocarcinoma

  18. Sepsis patients' renal manifestation on contrast-enhanced CT

    International Nuclear Information System (INIS)

    Sasaguri, K.; Yamaguchi, K.; Nakazono, T.; Mizuguchi, M.; Irie, H.

    2016-01-01

    Aim: To evaluate renal volume and attenuation changes in patients with sepsis on contrast-enhanced computed tomography (CT) with respect to the severity of sepsis. Materials and methods: Forty-four patients with sepsis who underwent CT before and after the onset of sepsis were retrospectively analysed. Renal volume and CT attenuation value of the renal cortex on contrast-enhanced CT were measured for each patient and changes in renal volume and CT attenuation value from before to after the onset of sepsis were calculated. The changes were correlated with the severity of sepsis (Sepsis-related Organ Failure Assessment [SOFA] score). The time course of the renal volume and CT attenuation changes were also evaluated. Results: Renal volume increased by 17.6% and CT attenuation value decreased by 19% after the onset of sepsis with statistically significant differences (p<0.001 for both renal volume and CT attenuation changes). The renal volume and CT attenuation changes had significant correlations with the SOFA score (r=0.36, p=0.018 and −0.43, p=0.005, respectively). The time course of the renal volume and CT attenuation changes seemed to be gradual compared to that of the SOFA score and to lag behind the peak of the SOFA score. Conclusion: In patients with sepsis, the renal volume increases and the CT attenuation value decreases in proportion to the severity of sepsis. The changes may lag behind the peak of severity of sepsis and can be observed for a relatively long time after a patient's recovery from sepsis. - Highlights: • The renal volume increases and the renal enhancement on contrast-enhanced CT decreases in patients with sepsis. • The degrees of these changes are correlated with severity of sepsis. • These changes may lag behind the peak of severity of sepsis and last for a long time after a patient's recovery from sepsis.

  19. Differential diagnosis between pulmonary tuberculosis and lung abscess by contrast enhanced CT

    International Nuclear Information System (INIS)

    Kanauchi, Tetsu; Hoshi, Toshiko; Konno, Miyuki; Hando, Yumiko

    2001-01-01

    The contrast enhanced CT findings in 14 patients with active tuberculosis and 26 patients with lung abscess were retrospectively analyzed. Reflecting the difference of pathogenesis between tuberculosis and abscess, the findings are widely different. The findings suggesting pulmonary tuberculosis rather than lung abscess were as follows; multiple and irregular necrotic areas, positive CT angiogram sign, no marginal enhancement surrounding necrosis. Contrast enhanced CT may help to distinguish pulmonary tuberculosis from lung abscess, especially in cases of caseous pneumonia showing broad consolidations or mass-like shadows. (author)

  20. Cervical lymph node metastasis of oral squamous cell carcinomas. CT enhancement and histopathological evaluations

    Energy Technology Data Exchange (ETDEWEB)

    Etoh, Yohei; Kimura, Takuji; Sasaki, Akira; Kishimoto, Koji; Matsumura, Tomohiro; Kishi, Kanji [Okayama Univ. (Japan). Dental School

    2000-06-01

    A comparison of the results of histopathological and enhanced CT examinations were carried out for 88 patients with oral squamous cell carcinomas who underwent neck dissection. CT scanning (5-mm thick section) images obtained during bolus/drip injection of Iopamidol were routinely taken through the neck. Ninety-two of 1634 nodes were histologically diagnosed as metastatic. Low density areas surrounding enhancement rims were metastatic nodal central necrosis or keratinization. Enhanced areas in many metastatic nodes were considered to be lymphatic architecture, not metastatic masses especially in the avascular keratinization. Enhanced CT produced accurate information of lymph node size, location, shape, grouping and spread from nodes to adjacent structures. However, it was considered that not every metastatic lymph node should show enlargement and/or enhancement. Improved assessment of solid metastatic features of lymph nodes (shape, size, and involvement) may be achieved with the aid of thin-thickness CT. (author)

  1. Cervical lymph node metastasis of oral squamous cell carcinomas. CT enhancement and histopathological evaluations

    International Nuclear Information System (INIS)

    Etoh, Yohei; Kimura, Takuji; Sasaki, Akira; Kishimoto, Koji; Matsumura, Tomohiro; Kishi, Kanji

    2000-01-01

    A comparison of the results of histopathological and enhanced CT examinations were carried out for 88 patients with oral squamous cell carcinomas who underwent neck dissection. CT scanning (5-mm thick section) images obtained during bolus/drip injection of Iopamidol were routinely taken through the neck. Ninety-two of 1634 nodes were histologically diagnosed as metastatic. Low density areas surrounding enhancement rims were metastatic nodal central necrosis or keratinization. Enhanced areas in many metastatic nodes were considered to be lymphatic architecture, not metastatic masses especially in the avascular keratinization. Enhanced CT produced accurate information of lymph node size, location, shape, grouping and spread from nodes to adjacent structures. However, it was considered that not every metastatic lymph node should show enlargement and/or enhancement. Improved assessment of solid metastatic features of lymph nodes (shape, size, and involvement) may be achieved with the aid of thin-thickness CT. (author)

  2. Intracranial ring enhancing lesions in dogs: a correlative CT scanning and neuropathologic study

    International Nuclear Information System (INIS)

    Wolf, Michael; Pedroia, Vince; Higgins, Robert J.; Koblik, Philip D.; Turrel, Jane M.; Owens, Jerry M.

    1995-01-01

    This retrospective analysis of 15 dogs with postcontrast ring enhancing brain lesions, each detected by a single Computed Tomography (CT) examination, searched for any association between their CT appearance and the pathologic diagnosis. In a subgroup of these dogs (n = 71) necropsied within 2 days of the last CT scan, we evaluated whether there was any anatomic correlation between the ring zone and the histopathologic features of the lesions. Our study consisted of eight dogs with primary brain tumors (3 meningiomas, 3 astrocytomas, 1 mixed glioma, 1 oligodendroglioma), 4 with metastatic brain tumors (2 fibrosarcomas, 1 mammary carcinoma, 1 melanoma) and 3 with non-neoplastic brain lesions (2 intraparenchymal hemorrhages, 1 pyogranulomatous meningoencephalitis). The overall size and shape of the contrast enhancing CT lesions, as well as the thickness, surface texture and degree of enhancement of the ring were subjectively evaluated. No association was found between the CT lesion characteristics and the pathologic diagnosis. In the sub-group of dogs euthanatized within 2 days of the CT examination, distinct histologic features which anatomically correlated with the zone of ring enhancement were found in 3 of 7 lesions. The findings of this study are consistent with those of ring-enhancing lesions in people, and indicates that CT ring enhancement is a nonspecific phenomenon which can occur in a variety of neoplastic and non-neoplastic lesions in the dog

  3. A comparison of iopamidol and ioxaglate in CT enhancement

    International Nuclear Information System (INIS)

    Del Favero, C.; Rossini, G.; Martegani, A.

    1993-01-01

    We evaluated the adverse reactions (AR) rate produced in patients to see if any difference, related to the different chemotoxicities of two low-osmolality contrast media (CM), could be detected. We compared the AR rate after intravenous administration for brain or body computed tomography (CT) enhancement of either the ionic CM ioxaglate 320 mgI/ml or the non-ionic iopamidol 300 mgI/ml at a dose of 0.8 gI/kg. Three hundred and thirty patients (164 ioxaglate, 166 iopamidol) were studied according to a randomized double-blind design. AR reported by the patient (subjective) and/or observed by the radiologist (objective) were recorded by the radiologist on the patient record card. Laboratory tests were performed prior to and 24 h after contrast administration. Fifty-nine mild to moderate AR occurred in 30 patients (18.3%) receiving ioxaglate, 4 mild to moderate AR occurred in 2 patients (1.2%) receiving iopamidol (P < 0.05). No severe AR occurred in either group. The results of our study are comparable to the available evidence from 16 comparative randomized trials of iopamidol versus ioxaglate both after intraarterial and intravenous administration that gave an overall odds ratio of 3.9 [confidence interval (CI) 95%=3.1-4.9]. The diagnostic efficacy of the two CM was comparable. This study showed that the non-ionic CM iopamidol was better tolerated than the ionic ioxaglate after intravenous administration. We conclude that the chemotoxicity of the molecule influences the AR when CM with comparable osmolality are administered. (orig.)

  4. IMPaCT - Integration of Missions, Programs, and Core Technologies

    Science.gov (United States)

    Balacuit, Carlos P.; Cutts, James A.; Peterson, Craig E.; Beauchamp, Patricia M.; Jones, Susan K.; Hang, Winnie N.; Dastur, Shahin D.

    2013-01-01

    IMPaCT enables comprehensive information on current NASA missions, prospective future missions, and the technologies that NASA is investing in, or considering investing in, to be accessed from a common Web-based interface. It allows dependencies to be established between missions and technology, and from this, the benefits of investing in individual technologies can be determined. The software also allows various scenarios for future missions to be explored against resource constraints, and the nominal cost and schedule of each mission to be modified in an effort to fit within a prescribed budget.

  5. Usefulness of percentage enhancement washout value calculated on unenhanced, contrast-enhanced, and delayed enhanced CT in adrenal masses: adenoma versus metastasis

    International Nuclear Information System (INIS)

    Sohn, Kyung Myung; Lee, Sung Yong; Lee, Keun Ho

    2003-01-01

    To determine the usefulness of percentage enhancement washout value calculated on unenhanced, enhanced and delayed enhanced CT scans for the characterization of adrenal masses. Forty adrenal masses less than 5 cm in size were assessed using a protocol consisting of unenhanced CT, enhanced CT 60 seconds after intravenous administration of contrast material, and delayed enhanced CT at 10 minutes. The CT attenuation value of adrenal tumors was estimated on each scan, and percentage enhancement washout value was calculated as follows:[(attenuation value at enhanced CT-attenuation value at delayed CT)/ (attenuation value at enhanced CT-attenuation value at unenhanced CT)x100]. An adrenal mass was considered benign if its percentage enhancement washout value was at the threshold value, set to 60% and 50%, or higher. The accuracy of the procedure was determined by comparing its findings with the final clinical diagnosis. Twenty-nine massess were benign and 11 were malignant. The mean percentage enhancement washout value of the former was significantly higher than that of the latter (66.7% vs. 21.8%; p<0.01). All adenomas except one had a washout value of more than 50%. With a percentage washout threshold of 60%, 35 of 40 lesions were correctly characterized as benign or malignant [sensitivity 82.7% (24/29), specificity 100% (11/11), accuracy 87.5% (35/40)]; with a threshold of 50%, 39 of 40 lesions were correctly characterized [(sensitivity 96.5% (28/29), specificity 100% (11/11), accuracy 97.5% (39/40)]. Percentage enhancement washout values are useful for characterizing an adrenal mass as benign or malignant. For characterization, a threshold value of 50% was more accurate than one of 60%

  6. Predicting IDH mutation status of intrahepatic cholangiocarcinomas based on contrast-enhanced CT features

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Yong [Nanjing Drum Tower Hospital Clinical College of Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Department of Radiology, Nanjing, Jiangsu Province (China); Chen, Jun [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Pathology, Nanjing, Jiangsu Province (China); Kong, Weiwei [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Oncology, Nanjing, Jiangsu Province (China); Mao, Liang; Qiu, Yudong [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Hepatopancreatobiliary Surgery, Nanjing, Jiangsu Province (China); Kong, Wentao [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Ultrasonography, Nanjing, Jiangsu Province (China); Zhou, Qun [Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Department of Radiology, Nanjing, Jiangsu Province (China); Zhou, Zhengyang; Zhu, Bin; He, Jian [Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Department of Radiology, Nanjing, Jiangsu Province (China); Wang, Zhongqiu [Jiangsu Province Hospital of Traditional Chinese Medicine, the Affiliated Hospital of Nanjing University of Chinese Medicine, Department of Radiology, Nanjing, Jiangsu Province (China)

    2018-01-15

    To explore the difference in contrast-enhanced computed tomography (CT) features of intrahepatic cholangiocarcinomas (ICCs) with different isocitrate dehydrogenase (IDH) mutation status. Clinicopathological and contrast-enhanced CT features of 78 patients with 78 ICCs were retrospectively analysed and compared based on IDH mutation status. There were 11 ICCs with IDH mutation (11/78, 14.1%) and 67 ICCs without IDH mutation (67/78, 85.9%). IDH-mutated ICCs showed intratumoral artery more often than IDH-wild ICCs (p = 0.023). Most ICCs with IDH mutation showed rim and internal enhancement (10/11, 90.9%), while ICCs without IDH mutation often appeared diffuse (26/67, 38.8%) or with no enhancement (4/67, 6.0%) in the arterial phase (p = 0.009). IDH-mutated ICCs showed significantly higher CT values, enhancement degrees and enhancement ratios in arterial and portal venous phases than IDH-wild ICCs (all p < 0.05). The CT value of tumours in the portal venous phase performed best in distinguishing ICCs with and without IDH mutation, with an area under the curve of 0.798 (p = 0.002). ICCs with and without IDH mutation differed significantly in arterial enhancement mode, and the tumour enhancement degree on multiphase contrast-enhanced CT was helpful in predicting IDH mutation status. (orig.)

  7. Scanning and contrast enhancement protocols for multi-slice CT in evaluation of the upper abdomen

    International Nuclear Information System (INIS)

    Awai, Kazuo; Onishi, Hiromitsu; Takada, Koichi; Yamaguchi, Yasuo; Eguchi, Nobuko; Hiraishi, Kumiko; Hori, Shinichi

    2000-01-01

    The advent of multi-slice CT is one of the quantum leaps in computed tomography since the introduction of helical CT. Multi-slice CT can rapidly scan a large longitudinal (z-axis) volume with high longitudinal resolution and low image artifacts. The rapid volume coverage speed of multi-slice CT can increase the difficulty in optimizing the delay time between the beginning of contrast material injection and the acquisition of images and we need accurate knowledge about optimal temporal window for adequate contrast enhancement. High z-axis resolution of multi-slice can improve the quality of three-dimensional images and MPR images and we must select adequate slice thickness and slice intervals in each case. We discuss basic considerations for adequate contrast enhancement and scanning protocols by multi-slice CT scanner in the upper abdomen. (author)

  8. Helical CT finding of carotid-cavernous fistula: a sign of early enhancing superior ophthalmic vein

    International Nuclear Information System (INIS)

    Kim, Jae Hyung; Na, Dong Gyu; Byun, Hong Sik; Ryoo, Jae Wook

    2000-01-01

    The purpose of this study was to determine the diagnostic value of a sign of early enhancing superior ophthalmic vein (SOV), as seen on helical CT images in patients with carotid-cavernous fistula (CCF). This study involved 16 patients with CCF and 28 control patients. Axial CT images with scanning delays of 30 seconds following bolus injection of contrast material (90 mL, 3 mL/sec) were obtained, and this procedure was followed by coronal CT imaging. To determine the presence or absence of early enhancement or, dilatation of the SOV, bulging of the cavernous sinus, and enlargement of extraocular muscle, CT images were analysed by three observers in a blinded, random manner. Early enhancement of SOV was determined to be present where enhancement of the SOV was similar to or stronger than that of the ipsilateral posterior cerebral artery. A sign of early enhancing SOV was seen in 14 of the 16 patients with CCF but in no control patients (88% sensitivity and 100% specificity). The respective sensitivity and specificity of other CT features were 71% and 100% (dilatation of the SOV, as seen on axial images), 60% and 83% (dilatation of the SOV, as seen on coronal images), 71% and 89% (dilatation of the cavernous sinus), and 65% and 98% (enlargement of extraocular muscle). A sign of early enhancing SOV is a characteristic and specific CT finding of CCF, and is useful for the diagnosis of CCF. (author)

  9. Histopathologic diversity of gastric cancers: Relationship between enhancement pattern on dynamic contrast-enhanced CT and histological type.

    Science.gov (United States)

    Tsurumaru, Daisuke; Miyasaka, Mitsutoshi; Muraki, Toshio; Nishie, Akihiro; Asayama, Yoshiki; Oki, Eiji; Oda, Yoshinao; Honda, Hiroshi

    2017-12-01

    To evaluate the diagnostic value of contrast-enhanced computed tomography gastrography (CE-CTG) to predict the histological type of gastric cancer. We analyzed 47 consecutive patients with resectable advanced gastric cancer preoperatively evaluated by multiphasic dynamic contrast-enhanced CT. Two radiologists independently reviewed the CT images and they determined the peak enhancement phase, and then measured the CT attenuation value of the gastric lesion for each phase. The histological types of gastric cancers were assigned to three groups as differentiated-type, undifferentiated-type, and mixed-type. We compared the peak enhancement phase of the three types and compared the CT attenuation values in each phase. The peak enhancement was significantly different between the three types of gastric cancers for both readers (reader 1, p=0.001; reader 2, p=0.009); most of the undifferentiated types had peak enhancement in the delayed phase. The CT attenuation values of undifferentiated type were significantly higher than those of differentiated or mixed type in the delayed phase according to both readers (reader 1, p=0.002; reader 2, p=0.004). CE-CTG could provide helpful information in diagnosing the histological type of gastric cancers preoperatively. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Prognostic significance of contrast-enhanced CT attenuation value in extrahepatic cholangiocarcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Asayama, Yoshiki [Kyushu University, Department of Advanced Imaging and Interventional Radiology, Graduate School of Medical Sciences, Fukuoka (Japan); Nishie, Akihiro; Ishigami, Kousei; Ushijima, Yasuhiro; Takayama, Yukihisa; Okamoto, Daisuke; Fujita, Nobuhiro; Honda, Hiroshi [Kyushu University, Departments of Clinical Radiology, Fukuoka (Japan); Ohtsuka, Takao [Kyushu University, Departments of Surgery and Oncology, Fukuoka (Japan); Yoshizumi, Tomoharu [Kyushu University, Departments of Surgery and Sciences, Fukuoka (Japan); Aishima, Shinichi [Saga University, Pathology and Microbiology, Faculty of Medicine, Saga (Japan); Kyushu University, Departments of Anatomic Pathology, Graduate School of Medical Sciences, Fukuoka (Japan); Oda, Yoshinao [Kyushu University, Departments of Anatomic Pathology, Graduate School of Medical Sciences, Fukuoka (Japan)

    2017-06-15

    To determine whether washout characteristics of dynamic contrast-enhanced computed tomography (CT) could predict survival in patients with extrahepatic cholangiocarcinoma (EHC). This study collected 46 resected cases. All cases were examined by dynamic contrast study on multidetector-row CT. Region-of-interest measurements were obtained at the non-enhanced, portal venous phase and delayed phase in the tumour and were used to calculate the washout ratio as follows: [(attenuation value at portal venous phase CT - attenuation value at delayed enhanced CT)/(attenuation value at portal venous phase CT - attenuation value at unenhanced CT)] x 100. On the basis of the median washout ratio, we classified the cases into two groups, a high-washout group and low-washout group. Associations between overall survival and various factors including washout rates were analysed. The median washout ratio was 29.4 %. Univariate analysis revealed that a lower washout ratio, venous invasion, lymphatic permeation and lymph node metastasis were associated with shorter survival. Multivariate analysis identified the lower washout ratio as an independent prognostic factor (hazard ratio, 3.768; p value, 0.027). The washout ratio obtained from the contrast-enhanced CT may be a useful imaging biomarker for the prediction of survival of patients with EHC. (orig.)

  11. {sup 18}F-FDG PET/CT imaging versus dynamic contrast-enhanced CT for staging and prognosis of inflammatory breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Champion, Laurence; Edeline, Veronique; Giraudet, Anne-Laure; Wartski, Myriam [Service de Medecine Nucleaire, Saint-Cloud (France); Lerebours, Florence [Service d' Oncologie Medicale, Saint-Cloud (France); Cherel, Pascal [Institut Curie, Hopital Rene Huguenin, Service de Radiologie, Saint-Cloud (France); Bellet, Dominique [Service de Medecine Nucleaire, Saint-Cloud (France); Universite Paris Descartes, Pharmacologie Chimique et Genetique and Imagerie, Inserm U1022 CNRS UMR 8151, Faculte des sciences pharmaceutiques et biologiques, Paris (France); Alberini, Jean-Louis [Service de Medecine Nucleaire, Saint-Cloud (France); Universite Versailles Saint-Quentin, Faculte de medecine, Saint-Quentin-en-Yvelines (France)

    2013-08-15

    Inflammatory breast cancer (IBC) is the most aggressive type of breast cancer with a poor prognosis. Locoregional staging is based on dynamic contrast-enhanced (DCE) CT or MRI. The aim of this study was to compare the performances of FDG PET/CT and DCE CT in locoregional staging of IBC and to assess their respective prognostic values. The study group comprised 50 women (median age: 51 {+-} 11 years) followed in our institution for IBC who underwent FDG PET/CT and DCE CT scans (median interval 5 {+-} 9 days). CT enhancement parameters were net maximal enhancement, net early enhancement and perfusion. The PET/CT scans showed intense FDG uptake in all primary tumours. Concordance rate between PET/CT and DCE CT for breast tumour localization was 92 %. No significant correlation was found between SUVmax and CT enhancement parameters in primary tumours (p > 0.6). PET/CT and DCE CT results were poorly correlated for skin infiltration (kappa = 0.19). Ipsilateral foci of increased axillary FDG uptake were found in 47 patients (median SUV: 7.9 {+-} 5.4), whereas enlarged axillary lymph nodes were observed on DCE CT in 43 patients. Results for axillary node involvement were fairly well correlated (kappa = 0.55). Nineteen patients (38 %) were found to be metastatic on PET/CT scan with a significant shorter progression-free survival than patients without distant lesions (p = 0.01). In the primary tumour, no statistically significant difference was observed between high and moderate tumour FDG uptake on survival, using an SUVmax cut-off of 5 (p = 0.7 and 0.9), or between high and low tumour enhancement on DCE CT (p > 0.8). FDG PET/CT imaging provided additional information concerning locoregional involvement to that provided by DCE CT on and allowed detection of distant metastases in the same whole-body procedure. Tumour FDG uptake or CT enhancement parameters were not correlated and were not found to have any prognostic value. (orig.)

  12. Contrast enhanced ultrasound in CT-undetermined focal liver lesions

    DEFF Research Database (Denmark)

    Sandrose, Sebastian; Karstrup, S.; Gerke, Oke

    2016-01-01

    , surgical resection, PET/CT and clinical follow-up. Results: The 78 included patients had 163 undetermined focal liver lesions, mean size 1.1 cm, range 0.1–5.3 cm. There were 18 malignant and 145 benign liver lesions, as defined by the standard of reference. In differentiating between benign vs. malignant...

  13. Contrast material-enhanced CT of the abdomen

    International Nuclear Information System (INIS)

    Fishman, E.K.; Kuhlman, J.E.; Garrity, M.; Paris, D.A.

    1988-01-01

    A randomized double-blind comparison of a nonionic contrast agent (Omnipaque) and an ionic contrast agent (Hypaque) was performed to determine any difference between the two agents in the quality and performance of computed body tomography (CT). A total of 40 patient studies were performed on a state-of-the-art CT scanner with similar scanning techniques. The contrast agent was administered intravenously as a rapid infusion in all cases. The image quality of the abdominal CT scans was good to excellent in all cases. There was no difference between the ionic and nonionic agents in terms of study quality. The 20 patients who received nonionic contrast agents had no major or minor reactions. Five of the 20 patients receiving the ionic contrast agent had a total of ten adverse reactions, including nausea and vomiting, nasal congestion, sneezing, and urticaria. The authors conclude that nonionic contrast agents provide high-quality CT scans equal to those provided by ionic agents and also result in fewer reactions and less discomfort

  14. Enhanced CT perfusion cut-off sign in midgut volvulus

    International Nuclear Information System (INIS)

    Henesch, Stephen M.; Jaramillo, Diego M.; Nance, Michael L.

    2006-01-01

    We present a case of malrotation with midgut volvulus in an infant in which we discovered a unique CT sign called the perfusion cut-off sign. We hope this case will help establish this crucial diagnosis in other cases. (orig.)

  15. Enhanced CT perfusion cut-off sign in midgut volvulus

    Energy Technology Data Exchange (ETDEWEB)

    Henesch, Stephen M.; Jaramillo, Diego M. [Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); Nance, Michael L. [Children' s Hospital of Philadelphia, Department of Surgery, Philadelphia, PA (United States)

    2006-04-15

    We present a case of malrotation with midgut volvulus in an infant in which we discovered a unique CT sign called the perfusion cut-off sign. We hope this case will help establish this crucial diagnosis in other cases. (orig.)

  16. Semi-quantitative assessment of tricuspid regurgitation on contrast-enhanced multidetector CT

    International Nuclear Information System (INIS)

    Groves, A.M.; Win, T.; Charman, S.C.; Wisbey, C.; Pepke-Zaba, J.; Coulden, R.A.

    2004-01-01

    AIM: To assess whether the early regurgitation of intravenous contrast medium into the inferior vena cava (IVC) and/or hepatic veins on computed tomography (CT), indicates tricuspid regurgitation (TR), and if so, whether it be used to grade severity. MATERIALS AND METHODS: We identified 86 consecutive patients that had been investigated for possible pulmonary endarterectomy at Papworth Hospital. From these, 61 patients were selected in whom CT, transthoracic echocardiography, and right heart catheterization (RHC) had been performed within 6 weeks. Using an arbitrary visual scale, the degree of TR assessed by intravenous contrast-enhanced CT was compared with echocardiography. Results were analysed using a kappa weighted statistical test. In addition, CT and echocardiographic assessments of TR severity were correlated with pulmonary artery pressure measurements obtained by RHC (Spearman's rank correlation coefficient). RESULTS: CT assessment of TR had a sensitivity of 90.4% and a specificity of 100% in detecting echocardiographic TR. For TR graded as more than trivial by echocardiography, sensitivity of CT was 100%. With respect to RHC data, the correlation between severity assessment of TR between CT and echocardiography using the Kappa weighted coefficient was 0.56 (moderately good agreement). With respect to RHC data, the correlation between mean pulmonary pressure and TR grading on CT and echocardiography was r=0.685 (p<0.001) and r=0.727 (p<0.001), respectively. CONCLUSION: Early opacification of the IVC or hepatic veins on first-pass contrast-enhanced CT almost invariably indicates TR. There is moderately good agreement between CT and echocardiographic assessment of the severity of TR. Both CT and echocardiographic grading of TR correlate well with RHC measurements of pulmonary artery pressure

  17. Hypervascular hepatocellular carcinomas: detection with gadoxetate disodium-enhanced MR imaging and multiphasic multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Onishi, Hiromitsu; Kim, Tonsok; Hori, Masatoshi; Nakaya, Yasuhiro; Tsuboyama, Takahiro; Nakamoto, Atsushi; Tatsumi, Mitsuaki; Tomiyama, Noriyuki [Osaka University Graduate School of Medicine, Department of Radiology, Suita, Osaka (Japan); Imai, Yasuharu [Ikeda Municipal Hospital, Department of Gastroenterology, Ikeda, Osaka (Japan); Nagano, Hiroaki [Osaka University Graduate School of Medicine, Department of Surgery, Suita, Osaka (Japan); Kumano, Seishi; Okada, Masahiro; Murakami, Takamichi [Kinki University School of Medicine, Department of Radiology, Osakasayama, Osaka (Japan); Takamura, Manabu [Ikeda Municipal Hospital, Department of Radiology, Ikeda, Osaka (Japan); Wakasa, Kenichi [Osaka City University Graduate School of Medicine, Department of Diagnostic Pathology, Osaka, Osaka (Japan)

    2012-04-15

    To retrospectively compare the accuracy of detection of hypervascular hepatocellular carcinoma (HCC) by multiphasic multidetector CT and by gadoxetate disodium-enhanced MR imaging. After ethical approval, we analysed a total of 73 hypervascular HCC lesions from 31 patients suspected of having HCC, who underwent both gadoxetate disodium-enhanced MR imaging and multiphasic multidetector CT. Five blinded observers independently reviewed CT images, as well as dynamic MR images alone and combined with hepatobiliary phase MR images. Diagnostic accuracy (Az values), sensitivities and positive predictive values were compared by using the Scheffe post hoc test. The mean Az value for dynamic and hepatobiliary phase MR combined (0.81) or dynamic MR images alone (0.78) was significantly higher than that for CT images (0.67, P < 0.001, 0.005, respectively). The mean sensitivity of the combined MR images (0.67) was significantly higher than that of dynamic MR alone (0.52, P < 0.05) or CT images (0.44, P < 0.05). The mean positive predictive values were 0.96, 0.95 and 0.94, for CT, dynamic MR alone and combined MR images, respectively. Compared with multiphasic multidetector CT, gadoxetate disodium-enhanced MR imaging combining dynamic and hepatobiliary phase images results in significantly improved sensitivity and diagnostic accuracy for detection of hypervascular HCC. (orig.)

  18. Low-Dose Contrast-Enhanced Breast CT Using Spectral Shaping Filters: An Experimental Study.

    Science.gov (United States)

    Makeev, Andrey; Glick, Stephen J

    2017-12-01

    Iodinated contrast-enhanced X-ray imaging of the breast has been studied with various modalities, including full-field digital mammography (FFDM), digital breast tomosynthesis (DBT), and dedicated breast CT. Contrast imaging with breast CT has a number of advantages over FFDM and DBT, including the lack of breast compression, and generation of fully isotropic 3-D reconstructions. Nonetheless, for breast CT to be considered as a viable tool for routine clinical use, it would be desirable to reduce radiation dose. One approach for dose reduction in breast CT is spectral shaping using X-ray filters. In this paper, two high atomic number filter materials are studied, namely, gadolinium (Gd) and erbium (Er), and compared with Al and Cu filters currently used in breast CT systems. Task-based performance is assessed by imaging a cylindrical poly(methyl methacrylate) phantom with iodine inserts on a benchtop breast CT system that emulates clinical breast CT. To evaluate detectability, a channelized hoteling observer (CHO) is used with sums of Laguerre-Gauss channels. It was observed that spectral shaping using Er and Gd filters substantially increased the dose efficiency (defined as signal-to-noise ratio of the CHO divided by mean glandular dose) as compared with kilovolt peak and filter settings used in commercial and prototype breast CT systems. These experimental phantom study results are encouraging for reducing dose of breast CT, however, further evaluation involving patients is needed.

  19. Diagnostic performance of Contrast-enhanced CT in Pyrrolizidine Alkaloids-induced Hepatic Sinusoidal Obstructive Syndrome

    Science.gov (United States)

    Kan, Xuefeng; Ye, Jin; Rong, Xinxin; Lu, Zhiwen; Li, Xin; Wang, Yong; Yang, Ling; Xu, Keshu; Song, Yuhu; Hou, Xiaohua

    2016-01-01

    Hepatic sinusoidal obstruction syndrome (HSOS) can be caused by pyrrolizidine alkaloids(PAs)-containing herbals. Since PAs exposure is obscure and clinical presentation of HSOS is unspecific, it is challenge to establish the diagnosis of PAs-induced HSOS. Gynura segetum is one of the most wide-use herbals containing PAs. The aim of our study is to describe the features of contrast-enhanced computed tomography (CT) in gynura segetum-induced HSOS, and then determine diagnostic performance of radiological signs. We retrospectively analyzed medical records and CT images of HSOS patients (71 cases) and the controls (222 cases) enrolled from January 1, 2008, to Oct 31, 2015. The common findings of contrast CT in PAs-induced HSOS included: ascites (100%), hepatomegaly (78.87%), gallbladder wall thickening (86.96%), pleural effusion (70.42%), hepatic vein narrowing (87.32%), patchy liver enhancement (92.96%), and heterogeneous hypoattenuation (100%); of these signs, patchy enhancement and heterogeneous hypoattenuation were valuable features. Then, the result of diagnostic performance demonstrated that contrast CT possessed better performance in diagnosing PAs-induced HSOS compared with various parameters of Seattle criteria. In conclusion, the patients with PAs-induced HSOS display distinct radiologic features at CT-scan, which reveals that contrast-enhanced CT provides an effective noninvasive method for diagnosing PAs-induced HSOS. PMID:27897243

  20. Hepatic scar in a case of healed candidiasis showing prolonged enhancement on CT

    International Nuclear Information System (INIS)

    Itai, Yuji; Yashiro, Naobumi

    1987-01-01

    A patient with acute myelocytic leukemia recovering from hepatic candidiasis after long-term administration of amphotericin B had large scar in the liver which showed prominent prolonged enhancement on postcontrast CT. Prolonged enhancement can occur in regions other than hepatic masses. (author)

  1. Hepatic scar in a case of healed candidiasis showing prolonged enhancement on CT

    Energy Technology Data Exchange (ETDEWEB)

    Itai, Yuji; Yashiro, Naobumi

    1987-08-01

    A patient with acute myelocytic leukemia recovering from hepatic candidiasis after long-term administration of amphotericin B had large scar in the liver which showed prominent prolonged enhancement on postcontrast CT. Prolonged enhancement can occur in regions other than hepatic masses.

  2. Hybrid imaging, PET-CT and SPECT-CT: What impact on nuclear medicine education and practice in France?

    International Nuclear Information System (INIS)

    Mundler, O.

    2009-01-01

    To define the policy of our specialty with a consensus opinion, a questionnaire entitled 'hybrid imaging' was sent to practicing nuclear medicine specialist physicians in France to obtain their opinion on the impact of this recent method in training and in the practice of nuclear medicine and on the relations between nuclear medicine specialists and other medical imaging specialists. This questionnaire, written by the office of the French Society of Nuclear Medicine (F.S.N.M.) and molecular imaging, was divided into four parts: Profile and experience in hybrid imaging, Relations with radiologists, Practice of CT scans with hybrid equipment, and the Future of the specialty and of training in nuclear medicine. The response rate was 60%, i.e. 374 completed questionnaires. Overall, the responses were uniform, whatever the respondent's experience, type and place of practice. Regular participation in hybrid imaging practice was the reply provided by the majority of respondents. In terms of relations with radiologists, such contacts existed in over 85% of cases and are considered as being of high quality in over 90% of cases. The vast majority of practitioners believe that hybrid imaging will become the standard. Opinions on the diagnostic use of CT scans are divided, as well as their interpretation by a radiologist, a nuclear medicine specialist or by both. In the opinion of the vast majority, hybrid equipment systems should be managed by nuclear medicine specialists. With regard to the future, nuclear medicine should remain an independent specialty with enhanced training in morphological imaging and a residency training program whose length should be increased to 5 years. (author)

  3. Non-tumor enhancement at the surgical margin on CT after the removal of brain tumors

    International Nuclear Information System (INIS)

    Adachi, Michito; Hosoya, Takaaki; Yamaguchi, Kohichi; Yamada, Kiyotada

    1992-01-01

    Marginal enhancement is occasionally seen at the surgical margin on CT after the total removal of brain tumors. This enhancement disappears in due time, and therefore we call it non-tumor enhancement. It is often difficult, however, to differentiate non-tumor enhancement from tumor recurrence. In this study, we attempted to determine the characteristics of non-tumor enhancement. The subjects of the study consisted of 15 patients with astrocytoma and one with metastatic tumor in whom sequential CT scans had been performed after total removal of the tumor. Based on the observation of these sequential CT scans, the characteristics of non-tumor enhancement were presumed to be as follows: (1) In four cases, enhancement at the surgical margin persisted more than four months after surgery and then disappeared. Therefore, these cases were considered non-tumor enhancement. Prolonged duration of enhancement such as that in these cases is not necessarily due to recurrence. Marginal enhancement within 3 mm in thickness and with a well-demarcated border like that of a flax is likely to be non-tumor enhancement. (author)

  4. Hybrid imaging with contrast enhanced CT scan: A nuclear physician's point of view

    International Nuclear Information System (INIS)

    Houzard, C.; Tychyj-Pinel, C.; Defez, D.; Valette, P.J.; Giammarile, F.; Houzard, C.; Valette, P.J.; Giammarile, F.

    2010-01-01

    The ongoing development of hybrid imaging, with physical association of CT scan and PET or SPECT scan, allows integrating morphological and functional information on a single exam. This important technological evolution changes diagnostic and therapeutic strategy in a major manner, essentially in oncology. The possibility to inject intravenously iodinated contrast media in order to enhance CT image contrast is still a controversial question in France. We present our experience in this domain by approaching technical problems and diagnostic advantages. (authors)

  5. Enhanced dual-phase spiral CT features of polypoid ampullary carcinoma

    International Nuclear Information System (INIS)

    Zeng Mengsu; Yan Fuhua; Zhou Kangrong; Chen Huiming; Chen Gang; Chen Jin

    2001-01-01

    Objective: To understand CT features of polypoid ampullary carcinoma by enhanced dual-phase spiral CT. Methods: 15 cases of polypoid ampullary carcinoma (PAC) confirmed by surgical and pathological results were studied with thin slice enhanced dual-phase spiral CT (including arterial and portal phase scanning)with retrospective analysis, the scanning parameters were 5 mm thickness and 1.0 pitch for arterial phase scanning, and 5 mm thickness and 5 mm space for portal phase scanning. Results: All cases could display an enhanced mass as local filling defect at the site of the duodenal Vater's ampulla during arterial and portal phase scanning, the tumors ranged in size from 1 cm to 5 cm with mean of 2.3 cm, all were accompanied with dilated intrahepatic and common bile duct, enlarged gallbladder and dilated pancreatic duct, except one case which had marked atrophy of the pancreatic body and tail. Conclusion: The thin slices enhanced dual-phase spiral CT could not only accurately define the level of obstruction, but also demonstrate an enhanced mass as direct CT sign of the PAC, which is crucial for diagnosis of the PAC

  6. Combined CT Angiography and CT Venography in Thromboembolic disease: clinical impact

    International Nuclear Information System (INIS)

    Bouzas, R.; Migueles, Y.; Gomez, S.; Mallo, R.; Garcia-Tejedor, J. L.; Diaz Vega, M. J.

    2002-01-01

    Combined CT Venography and Pulmonary Angiography was described in 1998 as a tool for diagnostic Thromboembolic Disease. The purpose is to relate our own experience with this technique in a population with suspected pulmonary embolism. 46 consecutive patients with suspected pulmonary embolism underwent combined CT Venography after Pulmonary CT Angiography to depict Deep Venous Thrombosis (DVT). CT Venography where obtained with a 3 minutes delay from injection, without additional intravenous contrast, from upper abdomen to fibular head. A prospective study from emergency reports where used. The reports where aimed by nine different radiologist at diary emergency room (images where not retrospective review). We report if a pulmonary embolus or deep venous thrombus or another alternative diagnostic where done. An endo luminal thrombus in any pulmonary arteries was assessed as a positive study for PE. A Thrombus in the leg veins or in an abdominal vein without diminished size of vein was assessed as an acute DVT. In those patients with a CT negative to Thromboembolic Disease was the clinician who decide if more proves where needed. Those patients without evidence in CT of Thromboembolic Disease where asked for symptoms related to the episode in a 3 months period after initial CT. Patients free of symptoms for 3 months without anticoagulation therapy where considered true negative for CT. CT shows Thromboembolic Disease in 23 of 46 patients. 21PE, 14 DVT 2 of 14 patients with DVT don't show PE, CT excluded thromboembolic disease in 23 patients and in 15 of those patients an alternative diagnostic was shown. In 22 of those 23 patients CT excluded correctly Thromboembolic Disease. One patient result in a false negative CT, Pulmonary Angiography of that patient shows us a subsegmentary embolus. (Author) 9 refs

  7. Distinguishing enhancing from nonenhancing renal masses with dual-source dual-energy CT: iodine quantification versus standard enhancement measurements.

    Science.gov (United States)

    Ascenti, Giorgio; Mileto, Achille; Krauss, Bernhard; Gaeta, Michele; Blandino, Alfredo; Scribano, Emanuele; Settineri, Nicola; Mazziotti, Silvio

    2013-08-01

    To compare the diagnostic accuracy of iodine quantification and standard enhancement measurements in distinguishing enhancing from nonenhancing renal masses. The Institutional Review Board approved this retrospective study conducted from data found in institutional patient databases and archives. Seventy-two renal masses were characterised as enhancing or nonenhancing using standard enhancement measurements (in HU) and iodine quantification (in mg/ml). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of standard enhancement measurements and iodine quantification were calculated from χ (2) tests of contingency with histopathology or imaging follow-up as the reference standard. Difference in accuracy was assessed by means of McNemar analysis. Sensitivity, specificity, PPV, NPV and diagnostic accuracy for standard enhancement measurements and iodine quantification were 77.7 %, 100 %, 100 %, 81.8 %, 89 % and 100 %, 94.4 %, 94.7, 100 % and 97 %, respectively. The McNemar analysis showed that the accuracy of iodine quantification was significantly better (P < 0.001) than that of standard enhancement measurements. Compared with standard enhancement measurements, whole-tumour iodine quantification is more accurate in distinguishing enhancing from nonenhancing renal masses. • Enhancement of renal lesions is important when differentiating benign from malignant tumours. • Dual-energy CT offers measurement of iodine uptake rather than mere enhancement values. • Whole-tumour iodine quantification seems more accurate than standard CT enhancement measurements.

  8. Invaded depth of extrahepatic bile duct cancer diagnosed on angiographic CT during late contrast enhancement

    International Nuclear Information System (INIS)

    Kikuyama, Masataka; Sasada, Yuzo; Koide, Shigeki; Hirai, Ritsuko; Oota, Yuji

    2006-01-01

    Thirteen patients with extrahepatic bile duct cancer were evaluated for enhancement pattern and tumor feature during late contrast enhancement on angiographic CT (AG-CT), performed before surgery. Eleven patients with late contrast enhancement had advanced cancers with invasion over the subserosal layer. Eight of these patients whose cancer had an irregular outer layer had invasion over the serosal layer (≥panc 1 b, General Rules for Surgical and Pathological Studies on Cancer of the Biliary Tract, Japanese Society of Biliary Surgery). Seven of the 13 patients had intra-pancreatic bile duct cancer. Among them, five had an irregular outer layer of the intra-pancreatic bile duct cancer; one of three with a wall thickness under 5 mm on AG-CT had panc 1 b invasion, and the other two had panc 2 (General Rules for Surgical and Pathological Studies on Cancer of the Biliary Tract, Japanese Society of Biliary Surgery) invasion. Two with a wall thickness over 5 mm on AG-CT had panc 2 invasion. These results suggest that late contrast enhancement on AG-CT is effective for diagnosing the depth of tumor invasion of the bile duct. (author)

  9. Impact of new technologies on dose reduction in CT

    International Nuclear Information System (INIS)

    Lee, Ting-Yim; Chhem, Rethy K.

    2010-01-01

    The introduction of slip ring technology enables helical CT scanning in the late 1980's and has rejuvenated CT's role in diagnostic imaging. Helical CT scanning has made possible whole body scanning in a single breath hold and computed tomography angiography (CTA) which has replaced invasive catheter based angiography in many cases because of its easy of operation and lesser risk to patients. However, a series of recent articles and accidents have heightened the concern of radiation risk from CT scanning. Undoubtedly, the radiation dose from CT studies, in particular, CCTA studies, are among the highest dose studies in diagnostic imaging. Nevertheless, CT has remained the workhorse of diagnostic imaging in emergent and non-emergent situations because of their ubiquitous presence in medical facilities from large academic to small regional hospitals and their round the clock accessibility due to their ease of use for both staff and patients as compared to MR scanners. The legitimate concern of radiation dose has sparked discussions on the risk vs benefit of CT scanning. It is recognized that newer CT applications, like CCTA and perfusion, will be severely curtailed unless radiation dose is reduced. This paper discusses the various hardware and software techniques developed to reduce radiation dose to patients in CT scanning. The current average effective dose of a CT study is ∼10 mSv, with the implementation of dose reduction techniques discussed herein; it is realistic to expect that the average effective dose may be decreased by 2-3 fold.

  10. The relationship between microvessels density and CT enhancement of the peripheral lung cancer

    International Nuclear Information System (INIS)

    Liu Shiyuan; Zhou Kangrong; Xiao Xiangsheng; Ye Tingjun; Zhang Zhiyong

    1999-01-01

    Objective: To investigate the relationship between microvessel density (MVD), clinical prognosis and CT enhancement of the peripheral lung cancer. Methods: 127 cases of peripheral lung cancer were examined with CT (87 cases retrospectively and 40 cases prospectively), and MVD were measured with immunohistochemical method by factor VIII on the specimens of the resected tumors. The results were analyzed and compared with CT enhancement, metastasis and prognosis. Results: The MVD was higher in the peripheral junction zone and interstitial areas than that in the parenchymal areas and necrotic zones of the tumors. Patients with nodal metastasis had higher MVD than those without nodal metastasis (56.9 +- 18.1 versus 43.8 +- 23.6, P 0.05); but the enhancement of the lung cancer correlated well with MVD (r 0.8874). Conclusions: Measurement of the microvessel density of tumor can determine the degree of angiogenesis of neoplasm and predict the metastasis or prognosis of the lung cancer. Angiogenesis not only constitutes the basis of enhancement of the tumor, but also determine the various degrees and patterns of enhancement. Spiral dynamic CT is the technique ideal to demonstrate the enhancement features, which might be helpful in making differential diagnosis of pulmonary nodules

  11. Diagnostic performance of contrast enhanced CT and 18F-FDG PET/CT in suspicious recurrence of biliary tract cancer after curative resection

    International Nuclear Information System (INIS)

    Lee, Yun-Gyoo; Bang, Yung-Jue; Han, Sae-Won; Oh, Do-Youn; Chie, Eui Kyu; Jang, Jin-Young; Im, Seock-Ah; Kim, Tae-You; Kim, Sun-Whe; Ha, Sung Whan

    2011-01-01

    Because of the late clinical presentation of biliary tract cancer (BTC), only 10% of patients are eligible for curative surgery. Even among those patients who have undergone curative surgery, most patients develop recurrent cancer. This study is to determine the clinical role of 18 F-FDG PET/CT during post-operative surveillance of suspected recurrent BTC based on symptoms, laboratory findings and contrast-enhanced CT (ceCT) findings. We consecutively enrolled 50 patients with BTC who underwent curative surgery. An 18 F-FDG PET/CT was obtained for assessment of recurrence based on clinical suspicion during post-operative surveillance. The final confirmation of recurrence was determined pathologically or clinically. When a pathologic confirmation was impossible or inconclusive, a clinical confirmation was used by radiologic correlation with subsequent follow-up ceCT at a minimum of 3-month intervals. Diagnostic efficacy was evaluated by comparing the results of ceCT and 18 F-FDG PET/CT with the final diagnosis. Among the 50 patients, 34(68%) were confirmed to have a recurrence. PET/CT showed higher sensitivity (88% vs. 76%, p = 0.16) and accuracy (82% vs. 66%, p = 0.11) for recurrence compared to ceCT, even though the difference was not significant. The positive (86% vs. 74%, p = 0.72) and negative predictive values for recurrence (73% vs. 47%, p = 0.55) were not significantly different between PET/CT and ceCT. However, an additional PET/CT on ceCT significantly improved the sensitivity than did a ceCT alone (94% [32/34] for PET/CT on ceCT vs. 76% [26/34] for ceCT alone, p = 0.03) without increasing the specificity, positive predictive value, and negative predictive value. 18 F-FDG PET/CT alone is not more sensitive or specific than ceCT in the detection of recurrent BTC after curative surgery. These results do not reach statistical significance, probably due to the low number of patients. However, an additional 18 F-FDG PET/CT on ceCT significantly improves the

  12. Wedge-shaped parenchymal enhancement peripheral to the hepatic hemangioma : two-phase spiral CT findings

    International Nuclear Information System (INIS)

    Kim, Kyoung Won; Kim, Tae Kyoung; Han, Joon Koo; Kim, Ah Young; Lee, Hyun Ju; Song, Chi Sung; Choi, Byung Ihn

    2000-01-01

    To determine the incidence of hepatic hemangiomas associated with wedge-shaped parenchymal enhancements adjacent to the tumors as seen on two-phase spiral CT images obtained during the hepatic arterial phase and to characterize the two-phase spiral CT findings of those hemangiomas. One hundred and eight consecutive hepatic hemangiomas in 63 patients who underwent two-phase spiral CT scanning during an 11-month period were included in this study. Two-phase spiral CT scans were obtained during the hepatic arterial phase (30-second delay) and portal venous phase (65-second delay) after injection of 120 mL of contrast material at a rate of 3 mL/sec. We evaluated the frequency with which wedge-shaped parenchymal enhancement was adjacent to the hemangiomas during the hepatic arterial phase and divided hemangiomas into two groups according to whether or not wedge-shaped parenchymal enhancement was noted (Group A and Group B). The presence of such enhancement in hemangiomas was correlated with tumor size and the grade of intratumoral enhancement. In 24 of 108 hemangiomas, wedge-shaped parenchymal enhancement adjacent to hepatic tumors was seen on two-phase CT images obtained during the hepatic arterial phase. Mean hemangioma size was 22mm in group A and 24mm in group B. There was no statistically significant relationship between lesion size and the presence of wedge-shaped parenchymal enhancement adjacent to a hemangioma. In 91.7% and 100% of tumors in Group A, and in 9.6% and 17.8% in Group B, hemangiomas showed more than 50% intratumoral enhancement during the arterial and portal venous phase, respectively. Wedge-shaped parenchymal enhancements peripheral to hepatic hemangiomas was more frequently found in tumors showing more than 50% intratumoral enhancement during these two phases (p less than 0.01). Wedge-shaped parenchymal enhancements is not uncommonly seen adjacent to hepatic hemangiomas on two-phase spiral CT images obtained during the hepatic arterial phase. A

  13. Application of Super-Resolution Convolutional Neural Network for Enhancing Image Resolution in Chest CT.

    Science.gov (United States)

    Umehara, Kensuke; Ota, Junko; Ishida, Takayuki

    2017-10-18

    In this study, the super-resolution convolutional neural network (SRCNN) scheme, which is the emerging deep-learning-based super-resolution method for enhancing image resolution in chest CT images, was applied and evaluated using the post-processing approach. For evaluation, 89 chest CT cases were sampled from The Cancer Imaging Archive. The 89 CT cases were divided randomly into 45 training cases and 44 external test cases. The SRCNN was trained using the training dataset. With the trained SRCNN, a high-resolution image was reconstructed from a low-resolution image, which was down-sampled from an original test image. For quantitative evaluation, two image quality metrics were measured and compared to those of the conventional linear interpolation methods. The image restoration quality of the SRCNN scheme was significantly higher than that of the linear interpolation methods (p < 0.001 or p < 0.05). The high-resolution image reconstructed by the SRCNN scheme was highly restored and comparable to the original reference image, in particular, for a ×2 magnification. These results indicate that the SRCNN scheme significantly outperforms the linear interpolation methods for enhancing image resolution in chest CT images. The results also suggest that SRCNN may become a potential solution for generating high-resolution CT images from standard CT images.

  14. Pathologic contrast enhancement of cerebral lesions: A comparative study using stereotactic CT, stereotactic MR imaging, and stereotactic biopsy

    International Nuclear Information System (INIS)

    Earnest, F. IV; Kelly, P.J.; Scheithauer, B.; Kall, B.; Cascino, T.L.; Ehman, R.L.; Forbes, G.

    1986-01-01

    The author compared the pattern and degree of Gd-DTPA dimeglumine contrast enhancement demonstrated on stereotactic MR images with that seen on stereotactic CT images obtained after conventional iodinated contrast agent enhancement and with histopathologic findings on sequential stereotactic brain biopsies. Stereotactic biopsies of the areas that enhanced on CT or MR imaging revealed tumor tissue with neovascularity. Tumor tissue with no or mild neovascularity did not enhance with contrast agent administration. Isolated tumor cells were frequently found beyond the margins of some primary brain neoplasms defined by contrast agent-enhanced MR imaging and CT. The histopathologic findings associated with pathologic contrast agent enhancement are presented

  15. Enhancing pattern of gastric carcinoma at dynamic incremental CT: correlation with gross and histologic findings

    International Nuclear Information System (INIS)

    Shin, Hong Seop; Lee, Dong Ho; Kim, Yoon Hwa; Ko, Young Tae; Lim, Joo Won; Yoon, Yup

    1996-01-01

    To evaluate the enhancing pattern of gastric carcinomas at dynamic incremental CT and to correlate it with pathologic findings. We retrospectively evaluated the enhancement pattern of stomach cancer on dynamic incremental CT of the 78 patients. All the lesions had been pathologically proved after surgery. The enhancement pattern was categorized as good or poor in the early phase;homogeneous, heterogeneous or ring enhancement;the presence or absence of delayed enhancement. There were 16 cases of early gastric cancer (EGC), and 62 cases of advanced gastric cancer(AGC). The Borrmann type of AGC were 1(n=1), 2(n=20), 3=(n=32), 4(n=8) and 5(n=1). The histologic patterns of AGC were tubular(n=49), signet ring cell(n=10), and mucinous(n=3). The enhancing patterns were compared with gross and histologic findings and delayed enhancement was correlated with pathologic evidence of desmoplasia. Good enhancement of tumor was seen in 24/41cases (58.5%) with AGC Borrmann type 3-5, in 6/21(28.6%) with AGC Borrmann type 1-2, and in 3/16(18.8%) with EGC (P<.05). By histologic pattern, good enhancement of tumor was seen in 8/10(80%) with signet ring cell type, in 21/49(42.9%) with tubular type, and in 1/3(33.3%) with mucinous type(P<.05). EGC was homogeneously enhanced in 14/16cases (87.5%), but AGC was heterogeneously enhanced in 33/62(53.2%), respectively(P<.01). There was no significant correlation between delayed enhancement and the presence of desmoplasia. AGC Borrmann type 3-5 and signet ring cell type have a tendency to show good enhancement and EGC is more homogeneously enhanced at dynamic incremental CT

  16. Acute appendicitis: sensitivity, specificity and diagnostic accuracy of thin-section contrast-enhanced CT findings

    International Nuclear Information System (INIS)

    Lee, Ji Yon; Choi, Dong Il; Park, Hae Won; Lee, Young Rae; Kook, Shin Ho; Kwang, Hyon Joo; Kim, Seung Kwon; Chung, Eun Chul

    2002-01-01

    To assess the sensitivity, specificity, and diagnostic accuracy of individual contrast-enhanced helical CT findings of acute appendicitis. We retrospectively reviewed the appendiceal helical CT scans, obtained after intravenous contrast administration (abdomen; 7-mm collimation, abdominopelvic junction; 5-mm collimation), of 50 patients with surgically proven acute appendicitis and 112 with alternative diagnoses. The following parameters were analysed by three radiologists: enlarged appendix (>6 mm in diameter), appendiceal wall thickening, appendiceal wall enhancement, no identification of the appendix, appendicolith(s), (appendiceal) intraluminal air, abscess, lymphadenopathy, terminal ileal wall thickening, focal cecal apical thickening, focal colonic wall thickening, and segmental colonic wall thickening. The CT findings of acute appendicitis that statistically distinguished it from alternative diagnoses were an enlarged appendix (sensitivity; 92%, specificity; 93%, diagnostic accuracy; 93%), appendiceal wall thickening (for these three parameters: 68%, 96% and 88%, respectively), periappendiceal fat stranding (90%, 79%, 82%), appendiceal wall enhancement (72%, 86%, 82%), appendicolith (16%, 100%, 74%), and focal cecal apical thickening (14%, 100%, 74%) (for each, p<0305). On thin-section contrast-enhanced helical CT, an enlarged appendix and periappendiceal fat stranding were found in 90% or more patients with acute appendicitis. Appendiceal wall thickening and enhancement were alearly demonstrated and significant findings for diagnosis. Less common but specific findings include appendicolith, focal cecal apical thickening and intramural air, can also help us establish a diagnosis of acute appendicitis

  17. VALIDITY OF CONTRAST ENHANCED CT IN THE ASSESSMENT OF ACUTE PANCREATITIS AND ITS RELATED COMPLICATIONS

    Directory of Open Access Journals (Sweden)

    Mannivanan

    2016-03-01

    Full Text Available BACKGROUND In the earlier days, ultrasonogram was considered as one of the most important investigation for pancreatitis, later the clinicians started using cholangiography in acute pancreatitis, but today CT is considered as a gold standard test in the diagnosis of acute pancreatitis. Though the sensitivity of CT in diagnosing acute pancreatitis was not studied much particularly in a mild case, but a good-quality contrast enhanced CT demonstrates distinct pancreatic and peri-pancreatic abnormalities. AIM To assess the importance of computed tomography in diagnosing acute pancreatitis and its related complications. MATERIALS AND METHODS A prospective study was conducted on 150 patients with clinically suspected pancreatitis. CT was performed on all the patients with Siemens Spiral CT scanner Sensation 16 slice. Oral contrast of was 1000 mL given one hour prior to the scan in the form of taking 250 mL every 15 mins. The CT severity index (CTSI and the necrosis point scoring was used to assess the severity of acute pancreatitis. All the complications related to acute pancreatitis were also assessed. RESULTS The CT analysis in the detection of acute pancreatitis showed the sensitivity of 100% and the positive predictive value of 97.3%. The severity index of acute pancreatitis based on the CT imaging had shown that majority of the patients are with moderate (60.6% level of acute pancreatitis. The necrosis point scoring showed that 54.6% of the patients had necrosis involving less than 30% of the pancreas. Among the various complications detected by CECT the commonest were pleural effusion and ascites. CONCLUSION CECT is the most important gold standard technique both for diagnosis as well as for predicting the prognosis in acute pancreatitis. The clinicians should routinely send the patient for the CT imaging whenever there is a suspicion of pancreatitis clinically.

  18. Dynamic contrast-enhanced CT (DCE-CT) as a potential biomarker in patients with metastatic renal cell carcinoma (mRCC)

    DEFF Research Database (Denmark)

    Mains, Jill Rachel; Donskov, Frede; Pedersen, Erik Morre

    Purpose To explore the impact of DCE-CT as a biomarker in mRCC.  Methods and Materials 12 patients with mRCC participating in a phase II trial with immunotherapy and bevacizumab and with a follow-up time of at least 2 years were included in this preliminary analysis. DCE-CT interpretation (max s...

  19. Decreased splenic enhancement on CT in traumatized hypotensive patients

    International Nuclear Information System (INIS)

    Berland, L.L.; VanDyke, J.A.

    1985-01-01

    Three patients with transient episodes of hypotension following blunt abdominal trauma incurred in motor vehicle accidents were examined by computed tomography within 6 hours of injury. None of the patients had splenic injury evident on autopsy, surgery, or clinical follow-up study (one case each), nor did they have other characteristic features of splenic infarction. However, in each case the spleen was less enhanced than the liver, leading to an erroneous impression in one patient that the splenic artery had been disrupted. Physiologic studies have shown that splenic perfusion decreases with sympathetic stimulation; this may have been the cause of the diminished enhancement. Decreased splenic enhancement should be interpreted cautiously in traumatized hypotensive patients

  20. Decreased splenic enhancement on CT in traumatized hypotensive patients

    Energy Technology Data Exchange (ETDEWEB)

    Berland, L.L.; VanDyke, J.A.

    1985-08-01

    Three patients with transient episodes of hypotension following blunt abdominal trauma incurred in motor vehicle accidents were examined by computed tomography within 6 hours of injury. None of the patients had splenic injury evident on autopsy, surgery, or clinical follow-up study (one case each), nor did they have other characteristic features of splenic infarction. However, in each case the spleen was less enhanced than the liver, leading to an erroneous impression in one patient that the splenic artery had been disrupted. Physiologic studies have shown that splenic perfusion decreases with sympathetic stimulation; this may have been the cause of the diminished enhancement. Decreased splenic enhancement should be interpreted cautiously in traumatized hypotensive patients.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-02-15

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

  2. Impact of iterative reconstruction on CT coronary calcium quantification

    DEFF Research Database (Denmark)

    Kurata, Akira; Dharampal, Anoeshka; Dedic, Admir

    2013-01-01

    We evaluated the influence of sinogram-affirmed iterative reconstruction (SAFIRE) on the coronary artery calcium (CAC) score by computed tomography (CT).......We evaluated the influence of sinogram-affirmed iterative reconstruction (SAFIRE) on the coronary artery calcium (CAC) score by computed tomography (CT)....

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1984-02-01

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

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

    International Nuclear Information System (INIS)

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

    1984-01-01

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

  5. Spiral CT in kidney: assumption of renal function by objective evaluation of renal cortical enhancement

    International Nuclear Information System (INIS)

    Choi, Bo Yoon; Lee, Jong Seok; Lee, Joon Woo; Myung, Jae Sung; Sim, Jung Suk; Seong, Chang Kyu; Kim, Seung Hyup; Choi, Guk Myeong; Chi, Seong Whi

    2000-01-01

    To correlate the degree of renal cortical enhancement, objectively evaluated by means of spiral CT with the serum level of creatinine, and to determine the extent to which this degree of enhancement may be used to detect renal parenchymal disease. Eighty patients (M:F = 50:30; age + 25-19, (mean 53) years) with available serum level of creatinine who underwent spiral CT between September and October 1999 were included in this study. In fifty patients the findings suggested hepatic or biliary diseases such as hepatoma, biliary cancer, or stone, while in thirty, renal diseases such as cyst, hematoma, or stone appeared to be present. Spiral CT imaging of the cortical phase was obtained at 30-40 seconds after the injection of 120 ml of non-ionic media at a rate of 3 ml/sec. The degree of renal cortical enhancement was calculated by dividing the CT attenuation number of renal cortex at the level of the renal hilum by the CT attenuation number of aorta at the same level. The degree of renal cortical enhancement was compared with the serum level of creatinine, and the degree of renal cortical enhancement in renal parenchymal disease with that of the normal group. Among eighty patients there were five with renal parenchymal disease and 75 with normal renal function. The ratio of the CT attenuation number of renal cortex to that of aorta at the level of the renal hilum ranged between 0.49 and 0.99 (mean, 0.79; standard deviation, 0.15). while the serum level of creatinine ranged between 0.6 and 3.2 mg/dl. There was significant correlation (coefficient of -0.346) and a statistically significant probability of 0.002 between the ratio of the CT attenuation numbers and the serum level of creatinine. There was a significant difference (statistically significant probability of less than 0.01) between those with renal parenchymal disease and the normal group. The use of spiral CT to measure the degree of renal cortical enhancement provides not only an effective index for

  6. Impact of CT in patients with sepsis of unknown origin

    International Nuclear Information System (INIS)

    Barkhausen, J.; Stoeblen, F.; Mueller, R.D.

    1999-01-01

    Purpose: To evaluate the diagnostic relevance of CT in patients with sepsis of unknown origin. Material and Methods: Sixty-three consecutive intensive care patients with suspicion of an abscess and negative or inconclusive previous radiological examinations were included. CT was performed using the helical technique. A total of 45 abdominal and 38 chest examinations were evaluated. Results: 5/38 examinations of the chest revealed the source of sepsis (pleural empyema 2, lung abscess 1, mediastinitis 1, retrosternal abscess 1). 7/45 abdominal CT examinations showed the source of sepsis (intraabdominal abscess 2, hepatic abscess 3, intestinal perforation 1, gangrenous colitis 1). Conclusion: CT is useful for the evaluation of patients with fever or sepsis without a known source. Due to the detection of a spetic focus by CT, 19% of the patients in our study could be immediately referred to causal therapy as percutaneous drainage or surgery. (orig.)

  7. Impact of CT in patients with sepsis of unknown origin

    Energy Technology Data Exchange (ETDEWEB)

    Barkhausen, J.; Stoeblen, F.; Mueller, R.D. [University Hospital Essen (Germany). Dept. of Radiology; Dominguez-Fernandez, E. [University Hospital Essen (Germany). Dept. of General Surgery; Henseke, P. [Nycomed-Amersham Arzneimittel GmbH, Muenchen (Germany)

    1999-09-01

    Purpose: To evaluate the diagnostic relevance of CT in patients with sepsis of unknown origin. Material and Methods: Sixty-three consecutive intensive care patients with suspicion of an abscess and negative or inconclusive previous radiological examinations were included. CT was performed using the helical technique. A total of 45 abdominal and 38 chest examinations were evaluated. Results: 5/38 examinations of the chest revealed the source of sepsis (pleural empyema 2, lung abscess 1, mediastinitis 1, retrosternal abscess 1). 7/45 abdominal CT examinations showed the source of sepsis (intraabdominal abscess 2, hepatic abscess 3, intestinal perforation 1, gangrenous colitis 1). Conclusion: CT is useful for the evaluation of patients with fever or sepsis without a known source. Due to the detection of a spetic focus by CT, 19% of the patients in our study could be immediately referred to causal therapy as percutaneous drainage or surgery. (orig.)

  8. FDG PET/CT Is Superior to Enhanced CT in Detecting Recurrent Subcentimeter Lesions in the Abdominopelvic Cavity in Colorectal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hai Jeon; Kim, Yu Kyeong; Kim, Sang Eun [Seoul National Univ. Bundang Hospital, Seoul (Korea, Republic of); Lee, Jong Jin [Asan Medical Center, Univ. of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2011-06-15

    This study aims to compare the performance of contrast enhanced computed tomography (CeCT) and 18 F fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in detecting small tumor implants and metastatic lymph nodes (LNs) in the abdominopelvic cavity in patients with colorectal cancer. We enrolled 16 patients who were clinically suspected of experiencing a recurrences (6 male, 10 female; mean age 61{+-}14 years). All subjects underwent CeCT and PET/CT, and the performance of these methods was compared with regard to detecting recurrences. The final diagnosis of a recurrence was made clinically. CeCT identified 38 lesions in 12 patients, all of which were detected by PET/CT. PET/CT found 27 additional lesions in 8 patients, comprising 9 seeding nodules (2 in the right upper quadrant of the abdomen and 7 in the pelvic cavity) and 18 LNs (2 celiac, 2 paraaortic, 2 hepatic hilar, 11 common iliac, 1 external iliac). Most additional lesions were located in the pelvic cavity (approximately 78% of seeding nodules that were detected solely by PET/CT was significantly higher compared with the CeCT and PET/CT confirmed nodules (5.5{+-}4.2 vs. 2.9{+-}2.5, p=0.03). The seeding nodules that were detected only by PET/CT were significantly smaller than the CeCT and PET/CT confirmed nodules (long axis:1.0{+-}0.3cm vs. 2.0{+-}1.1cm, p=0.001; short axis: 0.8{+-}0.3cm vs. 1.7{+-}0.9cm, p=0.001). Similarly, PET/CT only detected LNs were significantly smaller than CeCT and PET/CT identified LNs (0.7{+-}0.1cm vs. 2.3{+-}1.2cm, p<0.0001). PET/CT is superior to CeCT in detecting seeding nodules and metastatic LNs in patients with recurrent colorectal cancer. Specifically, PET/CT detects subcentimeter lesions in anatomically deformed pelvic cavities.

  9. Enhanced CT in the diagnosis of acute appendicitis to evaluate the severity of disease. Comparison of CT findings and histological diagnosis

    International Nuclear Information System (INIS)

    Mori, Yoshiko; Yamasaki, Michio; Furukawa, Akira; Takahashi, Masashi; Murata, Kiyoshi

    2001-01-01

    To assess the potential of CT in evaluating the histological severity of acute appendicitis in comparison with surgical and pathological findings. The CT images of 75 patients with surgically proven appendicitis, including 10 cases of catarrhal, 34 of phlegmonous, and 31 of gangrenous appendicitis, were retrospectively analyzed for the following five CT findings: hazy periappendiceal densities, enlarged appendix, increased enhancement of the appendiceal wall, increased enhancement of the periappendiceal intestinal wall, and deficiency of the appendiceal wall. By comparing all the CT findings and the pathological severity of appendicitis (catarrhal, phlegmonous, and gangrenous), the prevalence of the five CT findings was calculated for each pathological category. Abnormal CT findings were noted in only one case of catarrhal appendicitis. Increased enhancement of the appendiceal wall was observed in all 29 cases of phlegmonous appendicitis (100%), but in only 66.7% (18 cases) of gangrenous appendicitis. Deficiency of the appendiceal wall was more frequently observed in gangrenous (19/27, 70.4%) than phlegmonous appendicitis (4/29, 13.8%). Findings of enhanced CT provide useful information in evaluating the pathological severity of acute appendicitis. (author)

  10. Feasibility of contrast-enhanced cone-beam CT for target localization and treatment monitoring

    International Nuclear Information System (INIS)

    Rodal, Jan; Sovik, Aste; Skogmo, Hege Kippenes; Knudtsen, Ingerid Skjei; Malinen, Eirik

    2010-01-01

    A dog with a spontaneous maxillary tumour was given 40 Gy of fractionated radiotherapy. At five out of 10 fractions cone-beam CT (CBCT) imaging before and after administration of an iodinated contrast agent were performed. Contrast enhancement maps were overlaid on the pre-contrast CBCT images. The tumour was clearly visualized in the images thus produced.

  11. Characterization of tumor heterogeneity using dynamic contrast enhanced CT and FDG-PET in non-small cell lung cancer

    International Nuclear Information System (INIS)

    Elmpt, Wouter van; Das, Marco; Hüllner, Martin; Sharifi, Hoda; Zegers, Catharina M.L.; Reymen, Bart; Lambin, Philippe; Wildberger, Joachim E.; Troost, Esther G.C.; Veit-Haibach, Patrick; De Ruysscher, Dirk

    2013-01-01

    Purpose: Dynamic contrast-enhanced CT (DCE-CT) quantifies vasculature properties of tumors, whereas static FDG-PET/CT defines metabolic activity. Both imaging modalities are capable of showing intra-tumor heterogeneity. We investigated differences in vasculature properties within primary non-small cell lung cancer (NSCLC) tumors measured by DCE-CT and metabolic activity from FDG-PET/CT. Methods: Thirty three NSCLC patients were analyzed prior to treatment. FDG-PET/CT and DCE-CT were co-registered. The tumor was delineated and metabolic activity was segmented on the FDG-PET/CT in two regions: low (<50% maximum SUV) and high (⩾50% maximum SUV) metabolic uptake. Blood flow, blood volume and permeability were calculated using a maximum slope, deconvolution algorithm and a Patlak model. Correlations were assessed between perfusion parameters for the regions of interest. Results: DCE-CT provided additional information on vasculature and tumor heterogeneity that was not correlated to metabolic tumor activity. There was no significant difference between low and high metabolic active regions for any of the DCE-CT parameters. Furthermore, only moderate correlations between maximum SUV and DCE-CT parameters were observed. Conclusions: No direct correlation was observed between FDG-uptake and parameters extracted from DCE-CT. DCE-CT may provide complementary information to the characterization of primary NSCLC tumors over FDG-PET/CT imaging

  12. Dual-energy computed tomography for the assessment of early treatment effects of regorafenib in a preclinical tumor model: comparison with dynamic contrast-enhanced CT and conventional contrast-enhanced single-energy CT

    International Nuclear Information System (INIS)

    Knobloch, Gesine; Hamm, Bernd; Jost, Gregor; Pietsch, Hubertus; Huppertz, Alexander

    2014-01-01

    The potential diagnostic value of dual-energy computed tomography (DE-CT) compared to dynamic contrast-enhanced CT (DCE-CT) and conventional contrast-enhanced CT (CE-CT) in the assessment of early regorafenib treatment effects was evaluated in a preclinical setting. A rat GS9L glioma model was examined with contrast-enhanced dynamic DE-CT measurements (80 kV/140 kV) for 4 min before and on days 1 and 4 after the start of daily regorafenib or placebo treatment. Tumour time-density curves (0-240 s, 80 kV), DE-CT (60 s) derived iodine maps and the DCE-CT (0-30 s, 80 kV) based parameters blood flow (BF), blood volume (BV) and permeability (PMB) were calculated and compared to conventional CE-CT (60 s, 80 kV). The regorafenib group showed a marked decrease in the tumour time-density curve, a significantly lower iodine concentration and a significantly lower PMB on day 1 and 4 compared to baseline, which was not observed for the placebo group. CE-CT showed a significant decrease in tumour density on day 4 but not on day 1. The DE-CT-derived iodine concentrations correlated with PMB and BV but not with BF. DE-CT allows early treatment monitoring, which correlates with DCE-CT. Superior performance was observed compared to single-energy CE-CT. circle Regorafenib treatment response was evaluated by CT in a rat tumour model. (orig.)

  13. Dual-energy computed tomography for the assessment of early treatment effects of regorafenib in a preclinical tumor model: comparison with dynamic contrast-enhanced CT and conventional contrast-enhanced single-energy CT

    Energy Technology Data Exchange (ETDEWEB)

    Knobloch, Gesine; Hamm, Bernd [Charite - Universitaetsmedizin Berlin, Department of Radiology, Berlin (Germany); Jost, Gregor; Pietsch, Hubertus [Bayer Healthcare, MR and CT Contrast Media Research, Berlin (Germany); Huppertz, Alexander [Imaging Science Institute Charite - Siemens, Berlin (Germany)

    2014-08-15

    The potential diagnostic value of dual-energy computed tomography (DE-CT) compared to dynamic contrast-enhanced CT (DCE-CT) and conventional contrast-enhanced CT (CE-CT) in the assessment of early regorafenib treatment effects was evaluated in a preclinical setting. A rat GS9L glioma model was examined with contrast-enhanced dynamic DE-CT measurements (80 kV/140 kV) for 4 min before and on days 1 and 4 after the start of daily regorafenib or placebo treatment. Tumour time-density curves (0-240 s, 80 kV), DE-CT (60 s) derived iodine maps and the DCE-CT (0-30 s, 80 kV) based parameters blood flow (BF), blood volume (BV) and permeability (PMB) were calculated and compared to conventional CE-CT (60 s, 80 kV). The regorafenib group showed a marked decrease in the tumour time-density curve, a significantly lower iodine concentration and a significantly lower PMB on day 1 and 4 compared to baseline, which was not observed for the placebo group. CE-CT showed a significant decrease in tumour density on day 4 but not on day 1. The DE-CT-derived iodine concentrations correlated with PMB and BV but not with BF. DE-CT allows early treatment monitoring, which correlates with DCE-CT. Superior performance was observed compared to single-energy CE-CT. circle Regorafenib treatment response was evaluated by CT in a rat tumour model. (orig.)

  14. Evaluation of salmon calcitonin (sCT) enteric-coated capsule for enhanced absorption and GI tolerability in rats.

    Science.gov (United States)

    Wu, Lei; Zhang, Ge; Lu, Qin; Sun, Qian; Wang, Mulan; Li, Na; Gao, Zidong; Sun, Ya; Li, Tingting; Han, Deen; Yu, Xue; Wang, Lei; Sun, Wei; Zhao, Di; Wu, Yaning; Lu, Yang; Chen, Xijing

    2010-03-01

    Considering the chronic and repeated nature of salmon calcitonin (sCT) therapy, the oral route is a preferred route of administration. But, the oral bioavailability of sCT is very low due to enzymatic degradation and poor permeation across intestinal epithelial cells. It was the aim of this study to investigate the pharmacodynamic (PD), pharmacokinetic (PK), and mucosal injury characteristic of sCT oral delivery system. In this study, PD experiments were performed to find a suitable releasing region of sCT, an effect absorption enhancer, and an optimal mass ratio of sCT/enhancer. In addition, the PK experiments were designed to validate the absorption enhancement of this oral delivery system. Histopathological evaluations on the intestinal mucosa were carried out to assess any potential toxicity of the absorption enhancer. Through the PD research, we determined that oral sCT enteric-coated capsules containing sCT and citric acid (CA) with a ratio of 1:20 may be an adaptable delivery. PK study further proved that the oral absorption of sCT was enhanced from this delivery system. Finally, no damage on intestinal mucosa was observed when rats received the delivery system containing CA for up to 7 days. These results suggested that enteric-coated capsules with a certain amount of CA might give enhanced oral delivery of peptide drugs like sCT.

  15. Cardiac CT diagnosis in acute coronary syndrome. Significance of delayed enhancement effect in myocardium

    International Nuclear Information System (INIS)

    Yamaguchi, Takayoshi

    2007-01-01

    Authors have found that the effect in the title (DEE) exists in cardiac CT images due to the contrasting agent used for percutaneous coronary intervention (PCI) done shortly after the onset of acute coronary syndrome (ACS). To confirm the finding, they compared images of the cardiac CT and blood flow single photon emission computed tomography (SPECT) obtained several days after ACS. The cardiac CT images of 17 patients (M 15, F 2; average age 63.6 y) with ACS were obtained 20-30 min after the successfully attained emergent enhanced PCI, with the 4-row multi detector low CT (MDCT) machine Aquilion (Toshiba) in synchronization to R-R interval for processing to multiplanar reconstructed (MPR) images. Thereafter (5.5 days in average), myocardial SPECT was conducted with 99m Tc-tetrofosmin (740 MBq), of which images were also processed to MPR ones. The CT and SPECT images were compared in coronary arterial territories assigned to 17 segments in the left ventricle and to 20 areas in the Bull's-eye Map. Findings due to DEE in the former CT images were confirmed well correspondent with the lesion found in the latter SPECT, indicating that DEE is a useful tool for evaluation of ACS severity. (R.T.)

  16. The use of contrast-enhanced post Mortem CT in the detection of cardiovascular deaths.

    Directory of Open Access Journals (Sweden)

    Jonas Christoph Apitzsch

    Full Text Available OBJECTIVES: To evaluate the diagnostic value of contrast enhanced post mortem computed tomography (PMCT in comparison to non-enhanced post mortem CT in the detection of cardiovascular causes of death (COD. BACKGROUND: As autopsy rates decline, new methods to determine CODs are necessary. So contrast enhanced PMCT shall be evaluated in comparison to established non-enhanced PMCT in order to further improve the method. METHODS: In a prospective study, 20 corpses were examined using a 64-row multisclice CT (MSCT before and after intraarterial perfusion with a newly developed, barium-bearing contrast agent and ventilation of the lungs. The cause of death was determined in enhanced and unenhanced scans and a level of confidence (LOC was given by three experienced radiologists on a scale between 0 and 4. Results were compared to autopsy results as gold standard. Autopsy was performed blinded to PMCT-findings. RESULTS: The method allowed visualization of different types of cause of death. There was a significant improvement in LOC in enhanced scans compared to unenhanced scans as well as an improvement in the detection of COD. The cause of death could be determined in 19 out of 20 patients. CONCLUSIONS: PMCT is feasible and appears to be robust for diagnosing cardiovascular causes of death. When compared with unenhanced post-mortem CT intraarterial perfusion and pulmonary ventilation significantly improve visualization and diagnostic accuracy. These promising results warrant further studies.

  17. Non-hodgkin lymphoma containing low attenuation area at enhanced CT : correlation with histopathologic typing

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Hoon; Kim, Hyung Jin; Ahn, In Oak; Chung, Sung Hoon [College of Medicine, Gyeongsang National University, Jinju (Korea, Republic of); Park, Ji Hyun [Masan Koryo General Hospital, Masan (Korea, Republic of)

    1994-12-15

    To evaluate the frequently of low attenuation area in enhanced CT scans of non-Hodgkin lymphoma(NHL) and to find out if there is any pertinent relationship between this and the histopathologic classification. The authors reviewed CT scans in the newly-diagnosed 53 patients with NHL. We defined the low attenuation area as the one with CT attenuation value lower than that of the muscle, surrounding lesion, or other lymph nodes after contrast enhancement. NHL with the low attenuation areas were correlated with the histopathologic findings according to the classification based on the Working Formulation and the frequency of the lesion was evaluated. Of the 53 patients, the low attenuation area was found in 13 patients (25%) at CT. The histopathologic classification could be made in 12 patients, among whom one patient was classified as low-grade, six as intermediate-grade, and five as high-grade. Concerning the specific cell typing, the diffuse large cell type was most common in intermediate-grade NHL seen in five patients and the large cell, immunoblastic type was most common in high-grade NHL seen in three patients. The authors concluded that the low attenuation area within lymphoma is not an infrequent finding at CT, and there was no statistically significant correlation between this finding and the prognostic grading of the Working Formulation.

  18. Value of contrast enhanced CT scanning in the non-trauma emergency room patient

    International Nuclear Information System (INIS)

    Wood, L.P.; Parisi, M.; Finch, I.J.

    1990-01-01

    To determine the value of performing contrast CT in addition to non-contrast CT in the evaluation of acute non-traumatic central nervous system disorders, we retrospectively reviewed 322 cases originating from the emergency room at our institution. The most common indication for scanning was seizure activity (34% of total), followed by headache (30%), focal neurological deficit (10%), and altered mental status (8%). 75% of the noncontrast scans were normal. The contrast enhanced scan revealed abnormalities not evident on the non-contrast scan in only three of these cases, and the information did not alter patient management. We conclude that in the acute setting, if a non-contrast CT is normal, a contrast study is usually unnecessary. Therefore, given the additional risks of contrast infusion, the contrast study, if needed, is generally best obtained at a later date, after more careful evaluation of the patient's history and medical records. If the non-contrast CT scan is abnormal, a contrast enhanced CT scan may be beneficial, but, again, is often not needed to direct acute patient management. (orig.)

  19. Comparison of Xenon-Enhanced Area-Detector CT and Krypton Ventilation SPECT/CT for Assessment of Pulmonary Functional Loss and Disease Severity in Smokers.

    Science.gov (United States)

    Ohno, Yoshiharu; Fujisawa, Yasuko; Takenaka, Daisuke; Kaminaga, Shigeo; Seki, Shinichiro; Sugihara, Naoki; Yoshikawa, Takeshi

    2018-02-01

    The objective of this study was to compare the capability of xenon-enhanced area-detector CT (ADCT) performed with a subtraction technique and coregistered 81m Kr-ventilation SPECT/CT for the assessment of pulmonary functional loss and disease severity in smokers. Forty-six consecutive smokers (32 men and 14 women; mean age, 67.0 years) underwent prospective unenhanced and xenon-enhanced ADCT, 81m Kr-ventilation SPECT/CT, and pulmonary function tests. Disease severity was evaluated according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification. CT-based functional lung volume (FLV), the percentage of wall area to total airway area (WA%), and ventilated FLV on xenon-enhanced ADCT and SPECT/CT were calculated for each smoker. All indexes were correlated with percentage of forced expiratory volume in 1 second (%FEV 1 ) using step-wise regression analyses, and univariate and multivariate logistic regression analyses were performed. In addition, the diagnostic accuracy of the proposed model was compared with that of each radiologic index by means of McNemar analysis. Multivariate logistic regression showed that %FEV 1 was significantly affected (r = 0.77, r 2 = 0.59) by two factors: the first factor, ventilated FLV on xenon-enhanced ADCT (p < 0.0001); and the second factor, WA% (p = 0.004). Univariate logistic regression analyses indicated that all indexes significantly affected GOLD classification (p < 0.05). Multivariate logistic regression analyses revealed that ventilated FLV on xenon-enhanced ADCT and CT-based FLV significantly influenced GOLD classification (p < 0.0001). The diagnostic accuracy of the proposed model was significantly higher than that of ventilated FLV on SPECT/CT (p = 0.03) and WA% (p = 0.008). Xenon-enhanced ADCT is more effective than 81m Kr-ventilation SPECT/CT for the assessment of pulmonary functional loss and disease severity.

  20. Multiphase contrast-enhanced CT with highly concentrated contrast agent can be used for PET attenuation correction in integrated PET/CT imaging

    International Nuclear Information System (INIS)

    Aschoff, Philip; Plathow, Christian; Lichy, Matthias P.; Claussen, Claus D.; Pfannenberg, Christina; Beyer, Thomas; Erb, Gunter; Oeksuez, Mehmet Oe.

    2012-01-01

    State-of-the-art positron emission tomography/computed tomography (PET/CT) systems incorporate multislice CT technology, thus facilitating the acquisition of multiphase, contrast-enhanced CT data as part of integrated PET/CT imaging protocols. We assess the influence of a highly concentrated iodinated contrast medium (CM) on quantification and image quality following CT-based attenuation correction (CT-AC) in PET/CT. Twenty-eight patients with suspected malignant liver lesions were enrolled prospectively. PET/CT was performed 60 min after injection of 400 MBq of 18 F-fluorodeoxyglucose (FDG) and following the biphasic administration of an intravenous CM (400 mg iodine/ml, Iomeron 400). PET images were reconstructed with CT-AC using any of four acquired CT image sets: non-enhanced, pre-contrast (n-PET), arterial phase (art-PET), portal venous phase (pv-PET) and late phase (late-PET). Normal tissue activity and liver lesions were assessed visually and quantitatively on each PET/CT image set. Visual assessment of PET following CT-AC revealed no noticeable difference in image appearance or quality when using any of the four CT data sets for CT-AC. A total of 44 PET-positive liver lesions was identified in 21 of 28 patients. There were no false-negative or false-positive lesions on PET. Mean standardized uptake values (SUV) in 36 evaluable lesions were: 5.5 (n-PET), 5.8 (art-PET), 5.8 (pv-PET) and 5.8 (late-PET), with the highest mean increase in mean SUV of 6%. Mean SUV changes in liver background increased by up to 10% from n-PET to pv-PET. Multiphase CT data acquired with the use of highly concentrated CM can be used for qualitative assessment of liver lesions in torso FDG PET/CT. The influence on quantification of FDG uptake is small and negligible for most clinical applications. (orig.)

  1. Resolution enhancement of lung 4D-CT data using multiscale interphase iterative nonlocal means

    International Nuclear Information System (INIS)

    Zhang Yu; Yap, Pew-Thian; Wu Guorong; Feng Qianjin; Chen Wufan; Lian Jun; Shen Dinggang

    2013-01-01

    Purpose: Four-dimensional computer tomography (4D-CT) has been widely used in lung cancer radiotherapy due to its capability in providing important tumor motion information. However, the prolonged scanning duration required by 4D-CT causes considerable increase in radiation dose. To minimize the radiation-related health risk, radiation dose is often reduced at the expense of interslice spatial resolution. However, inadequate resolution in 4D-CT causes artifacts and increases uncertainty in tumor localization, which eventually results in extra damages of healthy tissues during radiotherapy. In this paper, the authors propose a novel postprocessing algorithm to enhance the resolution of lung 4D-CT data. Methods: The authors' premise is that anatomical information missing in one phase can be recovered from the complementary information embedded in other phases. The authors employ a patch-based mechanism to propagate information across phases for the reconstruction of intermediate slices in the longitudinal direction, where resolution is normally the lowest. Specifically, the structurally matching and spatially nearby patches are combined for reconstruction of each patch. For greater sensitivity to anatomical details, the authors employ a quad-tree technique to adaptively partition the image for more fine-grained refinement. The authors further devise an iterative strategy for significant enhancement of anatomical details. Results: The authors evaluated their algorithm using a publicly available lung data that consist of 10 4D-CT cases. The authors’ algorithm gives very promising results with significantly enhanced image structures and much less artifacts. Quantitative analysis shows that the authors’ algorithm increases peak signal-to-noise ratio by 3–4 dB and the structural similarity index by 3%–5% when compared with the standard interpolation-based algorithms. Conclusions: The authors have developed a new algorithm to improve the resolution of 4D-CT. It

  2. The relationship between contrast enhancement on CT and cerebral vasospasm in patient with subarachnoid hemorrhage

    International Nuclear Information System (INIS)

    Tazawa, Toshiaki; Mizukami, Masahiro; Kawase, Takeshi; Usami, Takashi; Togashi, Osamu

    1982-01-01

    Sixty patients with a single rupture of an aneurysm were subjected to study. Contrast enhanced CT (CECT) was performed by intravenous infusion of 100 ml of 60% meglumine iothalamate in 10 minutes. Post-contrast CT scans were repeated serially just after infusion, 15 minutes and 30 minutes later. Prominent increase in density in the region of the circle of Willis and its branches 30 minutes after infusion was considered as remarkable enhancement. In 17 (46%) out of 37 patients who underwent CECT within day 3, the contrast enhancement was remarkable. Transient or permanent symptomatic vasospasm occurred in 13 (76.5%) out of these 17 patients and the remaining 4 patients who underwent the operation with successful removal of subarachnoid clot within day 3 did not develop symptomatic vasospasm. Eight (67%) out of 12 patients operated within day 3, in whom post-operative CT showed incomplete removal of subarachnoid clot, developed transient or permanent symptomatic vasospasm. In only one (5%) out of 20 patients without remarkable enhancement, transient symptomatic vasospasm occurred. The abnormal contrast enhancement in the region of the circle of Willis and its branches within day 3 was closely related to the subsequent occurrence of vasospasm. Contrast enhanced CT was performed in 41 patients after day 3. There was no patient with remarkable enhancement on CECT. There was no relationship between the findings on CECT after day 3 and the occurrence of vasospasm. CECT within day 3 allows prediction of that patient destined for vasospasm and early removal of subarachnoid clot within day 3 may minimize the future development of vasospasm.(J.P.N.)

  3. Contrast-enhanced helical CT of the pancreas. Optimal timing of imaging for pancreatic tumor evaluation

    International Nuclear Information System (INIS)

    Koide, Kazuki; Sekiguchi, Ryuzo

    2001-01-01

    We performed three-phase helical CT in patients suspected pancreatic tumors and investigated the optimal timing of imaging for evaluation of the pancreatic mass. The pancreatic-phase was superior in detecting pancreatic tumors, including islet cell tumors that may show strong enhancement. However, portal vein-phase imaging was also superior in 16.7% of our patients. Taking into account examination for hepatic metastasis, helical CT of any pancreatic tumor should include images obtained in the pancreatic and portal vein phases. (author)

  4. Fluctuations in eGFR in relation to unenhanced and enhanced MRI and CT outpatients

    DEFF Research Database (Denmark)

    Azzouz, Manal; Rømsing, Janne; Thomsen, Henrik S

    2014-01-01

    OBJECTIVE: To study fluctuations in estimated glomerular filtration rate (eGFR) in relation to contrast medium (CM) enhanced magnetic resonance imaging (MRI) and computed tomography (CT) compared to control groups in outpatients. MATERIALS AND METHODS: eGFR was determined right before the imaging......-induced nephropathy (CIN) requirement when the definition s-creatinine ≥44μmol/l (0.5mg/dl) was used. CONCLUSIONS: eGFR in outpatients undergoing MRI or CT did vary independently of whether the patient received contrast or not. The findings probably reflect the natural variations in s-creatinine levels. This should...

  5. Dynamic contrast-enhanced CT appearances of the intraductal papillary neoplasms of the bile duct

    International Nuclear Information System (INIS)

    Song Fengxiang; Zhou Jianjun; Zeng Mengsu; Zhou Kangrong; Ding Yuqin; He Deming; Shi Yuxin; Zhou Jun

    2013-01-01

    Objective: To analyze the dynamic contrast-enhanced CT appearances of intraductal papillary neoplasms of the bile duct and improve its diagnostic accuracy. Methods: Sixteen patients with intraductal papillary neoplasms of the bile duct confirmed histopathologically after surgical operation underwent dynamic contrast-enhanced multi-detector row CT scans. All imaging data were reviewed and analyzed retrospectively in correlation with surgical and pathological findings. CT values of 38 well-visualized lesions in 12 of the 16 patients at the pre-contrast phase, arterial phase and venous phase were measured. Four of the 12 patients with 17 lesions had benign tumors, and 8 of the 12 patients with 21 lesions had malignant tumors. Comparisons of CT values at the three phases between the two groups were carried out using independent sample t test. The bile CT values were measured in these 12 cases, 40 normal volunteers, and 40 subjects with bile duct stones, and the Wilcoxon signed-rank test was applied to compare the bile CT values between tumor group and the normal group and between tumor group and the bile duct stone group. The diameters of the bile ducts proximal to and distal to tumors were also measured, and Fisher exact method was carried to analyze the data. Results: Lesions located at the left lobe in 8 out of the 16 patients, the right lobe in 1 case, both the left and right lobes in 1 case, the hepatic hilum in 1 case, the common bile duct in 3 cases, and both the right lobe and the common bile duct in 2 cases. Eleven lesions appeared as papillary masses, 3 as flat masses, 1 as mixed papillary and flat masses. In one case, tumor mass could not be definitely visualized, and only dilated bile ducts and stones were demonstrated. The mean CT values of the benign tumors were (25.8 ± 8.0), (37.7 ± 10.3) and (51.7 ± 17.1) HU respectively at pre-contrast phase, arterial phase, and venous phase, and the malignant tumors were (38.4 ± 10.2), (56.6 ± 18.0) and (68.4

  6. CT colonography: Diagnostic role of contrast enhancement of benign polyps and colorectal carcinoma

    International Nuclear Information System (INIS)

    Stoinova, V.; Nedevska, M.

    2006-01-01

    Full text: The aim of this study was to compare pre- and postcontrast CT attenuation values of benign colorectal polyps and carcinoma lesions detected by CT colonography, and to investigate whether contrast enhancement of these lesions can be potentially used for differentiation from residual fluid and feces. We retrospectively reviewed CT colonographic dataset of 120 patients. 35 benign polyps and 22 colorectal carcinomas were included in our study. All lesions were confirmed by colonoscopic biopsy or surgery. The difference in attenuation value between precontrast and postcontrast studies of polyps was statistically significant; the same was true for colorectal cancers. In the precontrast phase no statistically significant difference was observed between stool, polyps and cancers. The mean attenuation value of solid fecal residuals was 37 HU before and after contrast enhancement. Residual fluid do not take up contrast and the density does not change in the contrast-enhanced phase. The difference between postcontrast density of polyps and cancers with respect to density of stools and residual fluid was significant. The use of contrast medium could be helpful in CT colonography for discriminating polypoid benign lesions and colorectal cancer from fecal and fluid residuals

  7. Meta-analysis: Serum creatinine changes following contrast enhanced CT imaging

    International Nuclear Information System (INIS)

    Kooiman, Judith; Pasha, Sharif M.; Zondag, Wendy; Sijpkens, Yvo W.J.; Molen, Aart J. van der; Huisman, Menno V.; Dekkers, Olaf M.

    2012-01-01

    Purpose: Contrast induced nephropathy (CIN) is defined as a decrease in renal function following administration of contrast media. The aim of this meta-analysis was to asses the overall risk of CIN, chronic loss of kidney function and the need for renal replacement therapy (RRT) after intravenous contrast enhanced CT-scan. Secondly, we aimed to identify subgroups at increased risk for CIN. Materials and methods: A literature search in Pubmed, Medline, Embase and Cochrane databases was performed. Data extraction was carried out independently by two reviewers. Meta-analysis and meta-regression were performed using an exact likelihood approach. Results: Forty studies evaluating the incidence of CIN after CT were included. The pooled incidence of CIN was 6.4% (95% CI 5.0–8.1). The risk of RRT after CIN was low, 0.06% (95% CI 0.01–0.4). The decline in renal function persisted in 1.1% of patients (95% CI 0.6–2.1%). Patients with chronic kidney disease (odds ratio 2.26, p < 0.001) or diabetes mellitus (odds ratio 3.10, p < 0.001) were at increased risk for the development of CIN. Conclusion: CIN occurred in 6% of patients after contrast enhanced CT. In 1% of all patients undergoing contrast enhanced CT the decline in renal function persisted

  8. Meta-analysis: Serum creatinine changes following contrast enhanced CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kooiman, Judith, E-mail: j.kooiman@lumc.nl [Department of Thrombosis and Haemostasis, LUMC, Leiden (Netherlands); Pasha, Sharif M., E-mail: s.m.pasha@lumc.nl [Department of Thrombosis and Haemostasis, LUMC, Leiden (Netherlands); Zondag, Wendy, E-mail: w.zondag@lumc.nl [Department of Thrombosis and Haemostasis, LUMC, Leiden (Netherlands); Sijpkens, Yvo W.J., E-mail: ysijpens@bronovo.nl [Department of Nephrology, Bronovo Hospital, The Hague (Netherlands); Molen, Aart J. van der, E-mail: molen@lumc.nl [Department of Radiology, LUMC, Leiden (Netherlands); Huisman, Menno V., E-mail: m.v.huisman@lumc.nl [Department of Thrombosis and Haemostasis, LUMC, Leiden (Netherlands); Dekkers, Olaf M., E-mail: o.m.dekkers@lumc.nl [Department of Clinical Epidemiology and Department of Endocrinology, LUMC, Leiden (Netherlands)

    2012-10-15

    Purpose: Contrast induced nephropathy (CIN) is defined as a decrease in renal function following administration of contrast media. The aim of this meta-analysis was to asses the overall risk of CIN, chronic loss of kidney function and the need for renal replacement therapy (RRT) after intravenous contrast enhanced CT-scan. Secondly, we aimed to identify subgroups at increased risk for CIN. Materials and methods: A literature search in Pubmed, Medline, Embase and Cochrane databases was performed. Data extraction was carried out independently by two reviewers. Meta-analysis and meta-regression were performed using an exact likelihood approach. Results: Forty studies evaluating the incidence of CIN after CT were included. The pooled incidence of CIN was 6.4% (95% CI 5.0–8.1). The risk of RRT after CIN was low, 0.06% (95% CI 0.01–0.4). The decline in renal function persisted in 1.1% of patients (95% CI 0.6–2.1%). Patients with chronic kidney disease (odds ratio 2.26, p < 0.001) or diabetes mellitus (odds ratio 3.10, p < 0.001) were at increased risk for the development of CIN. Conclusion: CIN occurred in 6% of patients after contrast enhanced CT. In 1% of all patients undergoing contrast enhanced CT the decline in renal function persisted.

  9. Hepatic hemangioma: contrast enhancement patterns on two-phase spiral CT

    International Nuclear Information System (INIS)

    Yun, Eun Joo; Choi, Byung Ihn; Han, Joon Koo; Jang, Hyun Jung; Kim, Tae Kyoung; Kim, Ah Young; Lee, Ki Yeol

    1998-01-01

    To evaluate contrast enhancement patterns of hemangioma according to size, as seen during the arterial and portal venous phase of spiral CT. Overall, the most common enhancement pattern was peripheral high (44/82, 53.7%), during the arterial and portal venous phase. The second and third most common patterns were uniform high (11/82, 13.4%) and peripheral high-uniform high (9/82, 11.0%), also during the arterial and portal venous phase. In tumors smaller than 20 mm, low-low attenuation was seen in eight (9.8%), and iso-low attenuation in two (2.4%), during the arterial and portal venous phase, respectively. On two-phase spiral CT, the most common enhancement pattern of hemangioma was peripheral high, seen during the arterial and portal venous phase. However, a small hemangioma less than 2cm may show atypical patterns, including low and iso attenuation. (author). 23 refs., 1 tab., 4 figs

  10. FDG uptake on PET and enhancement on CT or MRI in hepatocellular carcinoma (HCC)

    International Nuclear Information System (INIS)

    Ko, K. H.; Yun, M.; Kim, M. J.; Ryu, Y. H.; Lee, J. D.

    2002-01-01

    To correlate between FDG PET and enhancement pattern on CT and MRI and assess the factors affecting FDG uptake in HCC. Thirty seven nontreated HCC from 34 pts (M:F=30:4, mean age 53) were enrolled. All cases were histologically diagnosed and classified according to Edmonson and Steiner's grading. Tumor FDG uptake was visually assessed on a scale of 0 to 3 compared to the adjacent liver. (0 liver and 3>>liver) and was semi-quantitatively analyzed using SUV. Enhancement pattern on CT and MRI was classified into 3 groups according to signal intensity or density in arterial and portal phase (GroupI: hyperintense-hypointense, GroupII: isointense-hypointense, GroupIII: hypointense-hypointense). Tumor FDG uptake was correlated with enhancement pattern, grade, size and serum aFP level. The tumor ranged from 1.5cm to 20cm. Of the 37 cases, 19(51%) had positive FDG uptake (2 or 3), while 18(49%) were negative (0 or 1). The correlation between FDG uptake and enhancement pattern was statistically insignificant. Lower FDG uptake was associated with lower tumor grade and/or smaller tumor size (P<0.005). FDG uptake of HCC seems to be useful in predicting the differentiation of the tumor and may be prognostic. Although the significance of dynamic enhancement pattern on CT or MRI is yet controversial, it has no specific correlation with FDG uptake and grade on the tumor in this study

  11. Evaluation of residual hepatocellular carcinoma after transcatheter arterial chemoembolization: Comparison between contrast-enhanced helical CT and contrast-enhanced power doppler ultrasonography

    International Nuclear Information System (INIS)

    Kim, Seung Hoon; Lim, Hyo Keun; Lee, Won Jae

    2001-01-01

    To evaluate the effectiveness of contrast-enhanced helical CT and contrast-enhanced power doppler ultrasonography (PDUS) in assessing the therapeutic effect of transcatheter arterial chemoembolization (TACE) in hepatocellular carcinomas (HCCs). The follow-up contrast-enhanced helical CT and contrast-enhanced PDUS were performed for twenty-nine nodular HCCs from twelve patients previously treated with TACE. We defined the residual HCCs as intratumoral enhancing area on contrast-enhanced helical CT and color signal on contrast-enhanced PDUS. The interval between two examinations was less than 2 weeks (mean, 9 days). Two radiologists evaluated two examinations by consensus, and the results of these two examination were compared with the findings of other examinations including CT, angiography, and/or pathology to calculate the sensitivity, specificity and accuracy of two examinations. Of the 29 HCCs, 20 had residual HCCs whereas no residual HCCs in 9 HCCs on pathologic examination and/or follow-up radiologic study. The sensitivity, sensitivity and accuracy of contrast-enhanced helical CT were 65 (13/20), 89 (8/9), and 72% (21/29) while those of contrast-enhanced PDUS were 100 (20/20), 89 (8/9) and 97% (28/29), respectively. A microbubble contrast-enhanced PDUS was more effective in the detection of residual tumor in HCCs following TACE than contrast-enhanced helical CT.

  12. Iodide and xenon enhancement of computed tomography (CT) in multiple sclerosis (MS)

    International Nuclear Information System (INIS)

    Radue, E.W.; Kendall, B.E.

    1978-01-01

    The characteristic findings on computed tomography (CT) in multiple sclerosis (MS) are discussed. In a series of 49 cases plain CT was normal in 21 (43%), cerebral atrophy alone was present in 17 (35%) and plaques were visible in 11 (23%). These were most often adjacent to the lateral ventricles (14 plaques) and in the parietal white matter (10 plaques). CT was performed after the intravenous administration of iodide in 16 of these cases. Two patients with low attenuation plaques were scanned with xenon enhancement; the plaques absorbed less xenon than the corresponding contralateral brain substance and additional, previously isodense plaques were revealed. In one case the white matter absorbed much less xenon than normal and its uptake relative to grey matter was reduced. (orig.) [de

  13. Resolution enhancement of lung 4D-CT via group-sparsity

    International Nuclear Information System (INIS)

    Bhavsar, Arnav; Wu, Guorong; Shen, Dinggang; Lian, Jun

    2013-01-01

    Purpose: 4D-CT typically delivers more accurate information about anatomical structures in the lung, over 3D-CT, due to its ability to capture visual information of the lung motion across different respiratory phases. This helps to better determine the dose during radiation therapy for lung cancer. However, a critical concern with 4D-CT that substantially compromises this advantage is the low superior-inferior resolution due to less number of acquired slices, in order to control the CT radiation dose. To address this limitation, the authors propose an approach to reconstruct missing intermediate slices, so as to improve the superior-inferior resolution.Methods: In this method the authors exploit the observation that sampling information across respiratory phases in 4D-CT can be complimentary due to lung motion. The authors’ approach uses this locally complimentary information across phases in a patch-based sparse-representation framework. Moreover, unlike some recent approaches that treat local patches independently, the authors’ approach employs the group-sparsity framework that imposes neighborhood and similarity constraints between patches. This helps in mitigating the trade-off between noise robustness and structure preservation, which is an important consideration in resolution enhancement. The authors discuss the regularizing ability of group-sparsity, which helps in reducing the effect of noise and enables better structural localization and enhancement.Results: The authors perform extensive experiments on the publicly available DIR-Lab Lung 4D-CT dataset [R. Castillo, E. Castillo, R. Guerra, V. Johnson, T. McPhail, A. Garg, and T. Guerrero, “A framework for evaluation of deformable image registration spatial accuracy using large landmark point sets,” Phys. Med. Biol. 54, 1849–1870 (2009)]. First, the authors carry out empirical parametric analysis of some important parameters in their approach. The authors then demonstrate, qualitatively as well as

  14. Peripancreatic vascular abnormalities complicating acute pancreatitis: contrast-enhanced helical CT findings

    International Nuclear Information System (INIS)

    Mortele, Koenraad J.; Mergo, Patricia J.; Taylor, Helena M.; Wiesner, Walter; Cantisani, Vito; Ernst, Michael D.; Kalantari, Babak N.; Ros, Pablo R.

    2004-01-01

    Objective: To determine the prevalence and morphologic helical computed tomography (CT) features of peripancreatic vascular abnormalities in patients with acute pancreatic inflammatory disease in correlation with the severity of the pancreatitis. Materials and methods: One hundred and fifty-nine contrast-enhanced helical CT scans of 100 consecutive patients with acute pancreatitis were retrospectively and independently reviewed by three observers. CT scans were scored using the CT severity index (CTSI): pancreatitis was graded as mild (0-2 points), moderate (3-6 points), and severe (7-10 points). Interobserver agreement for both the CT severity index and the presence of peripancreatic vascular abnormalities was calculated (K-statistic). Correlation between the prevalence of complications and the degree of pancreatitis was estimated using Fisher's exact test. Results: The severity of pancreatitis was graded as mild (n=59 scans), moderate (n=82 scans), and severe (n=18 scans). Venous abnormalities detected included splenic vein (SV) thrombosis (31 scans, 19 patients), superior mesenteric vein (SMV) thrombosis (20 scans, 14 patients), and portal vein (PV) thrombosis (17 scans, 13 patients). Arterial hemorrhage occurred in five patients (6 scans). In our series, no cases of arterial pseudoaneurysm formation were detected. The interobserver agreement range for scoring the degree of pancreatitis and the overall presence of major vascular abnormalities was 75.5-79.2 and 86.2-98.8%, respectively. The presence of the vascular abnormalities in correlation with the severity of pancreatitis was variable. Conclusion: Vascular abnormalities are relatively common CT findings in association with acute pancreatitis. The CT severity index is insufficiently accurate in predicting some of these complications since no statistically significant correlation between their prevalence and the severity of pancreatitis could be established

  15. Contrast between hypervascularized liver lesions and hepatic parenchyma. Early dynamic PET versus contrast-enhanced CT

    International Nuclear Information System (INIS)

    Freesmeyer, M.; Winkens, T.; Schierz, J.-H.

    2014-01-01

    To detect hypervascularized liver lesions, early dynamic (ED) 18 F-FDG PET may be an alternative when contrast-enhanced (CE) imaging is infeasible. This retrospective pilot analysis compared contrast between such lesions and liver parenchyma, an important objective image quality variable, in ED PET versus CE CT. Twenty-eight hypervascularized liver lesions detected by CE CT [21 (75%) hepatocellular carcinomas; mean (range) diameter 4.9 ± 3.5 (1-14) cm] in 20 patients were scanned with ED PET. Using regions of interest, maximum and mean lesional and parenchymal signals at baseline, arterial and venous phases were calculated for ED PET and CE CT. Lesional/parenchymal signal ratio was significantly higher (P < 0.005) with ED PET versus CE CT at the arterial phase and similar between the methods at the venous phase. In liver imaging, ED PET generates greater lesional-parenchymal contrast during the arterial phase than does CE CT; these observations should be formally, prospectively evaluated. (author)

  16. Differentiation between tuberculosis and primary tumors in the adrenal gland: evaluation with contrast-enhanced CT

    International Nuclear Information System (INIS)

    Yang, Zhi-Gang; Guo, Ying-Kun; Li, Yuan; Min, Peng-Qiu; Yu, Jian-Qun; Ma, En-Sen

    2006-01-01

    The aim of the present study is to determine imaging criteria for differentiating tuberculosis from primary tumors in the adrenal gland on contrast-enhanced CT. Non-contrast and contrast-enhanced CT features in 108 patients with adrenal tuberculosis (n=34) and primary tumor (n=74) were retrospectively assessed for the location, size, calcification and enhancement patterns. The primary tumors included 41 adenomas, 11 pheochromocytomas, 4 carcinomas, 3 lymphomas, 6 myelolipomas, 6 ganglioneuromas, 2 neurilemmomas and 1 ganglioneuroblastoma. Biochemical investigation was performed for all patients. Of the tuberculosis cases, 31 (91%) invaded with bilateral involvement, while 7 (9%) of the primary tumors invaded with bilateral involvement (P<0.001). Tuberculosis often showed calcification (20 of 34; 59%), whereas primary tumors infrequently showed calcification (6 of 74; 8%; P<0.001). Low attenuation in the center with peripheral rim enhancement was more commonly seen in tuberculosis (16 of 34; 47%) than in primary tumors (7 of 74; 9%; P<0.001). In the determination of tuberculosis, the highest sensitivity (91%) and accuracy (91%) were obtained with bilateral involvement, and the highest specificity (99%) was obtained with the contour preserved. In the determination of primary tumors using a combination of having unilateral involvement and being mass-like, the outcome was a sensitivity of 91%, specificity of 94% and accuracy of 92%. CT findings can differentiate tuberculosis from a primary tumor of the adrenal glands with high sensitivity and an acceptable specificity when combined with the endocrinological examination. (orig.)

  17. A comparative study of FDG PET/CT and enhanced multi-detector CT for detecting liver metastasis according to the size and location.

    Science.gov (United States)

    Park, Jung Mi; Kim, Il Young; Kim, Sang Won; Lee, Sang Mi; Kim, Hyun Gi; Kim, Shin Young; Shin, Hyung Chul

    2013-04-01

    The aim of this study was to compare the diagnosability between (18)F-fluorodeoxyglucose (FDG) PET/CT and enhanced multi-detector CT (MDCT) for the detection of liver metastasis (LM) according to the size and location in liver and to evaluate standard maximum standardized uptake values (SUVmax) of all liver metastatic lesions. One hundred two consecutive patients with malignancy who underwent both FDG PET/CT and MDCT for LM evaluation were retrospectively reviewed. Among them, 56 patients with LM were enrolled in this study. LM was confirmed by follow-up imaging studies after at least 6 months or by histopathology. FDG PET/CT and MDCT images were visually analyzed using three-point scale by the consensus of two radiologists and two nuclear medicine physicians. The size and location (central vs. sub-capsular) of the all liver lesions were evaluated using MDCT images. Furthermore, SUVmax of all liver lesions on FDG PET/CT images were calculated. A total of 146 liver lesions were detected by FDG PET/CT and MDCT and 142 of the lesions were diagnosed as LM. The detection rates of MDCT and FDG PET/CT for LM by visual analysis were 77 and 78%, respectively. There was no significant difference of detection rate according to the overall location and size of the lesions. However, FDG PET/CT was more sensitive than MDCT for detecting small and sub-capsular LM. The detection rate of FDG PET/CT for LM was 68% by the cutoff SUVmax of 2.7. Although the diagnosabilities of MDCT and FDG PET/CT for detecting LM were comparable, FDG PET/CT is superior to MDCT for detecting small LM located in the sub-capsular portion of liver.

  18. Contrast-enhanced computed tomography does not improve the diagnostic value of parathyroid dual-phase MIBI SPECT/CT

    DEFF Research Database (Denmark)

    Andersen, Trine B; Aleksyniene, Ramune; Boldsen, Søren K

    2018-01-01

    OBJECTIVE: The aim of this study was to investigate the contribution of contrast-enhanced computed tomography (CE-CT) to the localization of parathyroid adenomas compared with the dual-phase Tc-99m MIBI SPECT with low-dose CT (LD-CT). PATIENTS AND METHODS: This retrospective study included...... consecutive patients with primary hyperparathyroidism who underwent a preoperative dual-phase MIBI SPECT/CT followed by surgical resection. The standard of care was dual-phase MIBI SPECT/CT, acquired with LD-CT in the early phase and CE-CT in the late phase (SPECT/CE-CT). The presence and localization...... of positive sites were extracted from study reports. To examine the role of CE-CT, patient cases were independently re-reviewed, with the early LD-CT fused with early and late SPECT (SPECT/LD-CT). The two SPECT/CT methods were compared for sensitivity, and the positive predictive value and histopathology were...

  19. Prognostic criteria in acute pancreatitis: importance of assessment of pancreatic necrosis by contrast-enhanced CT

    International Nuclear Information System (INIS)

    Echevarria, F.; Martinez, B.; Lopez, F.; Vuelta, R.V.

    1997-01-01

    To compare the value of the clinical criteria of Ranson, the classical tomographic criteria of Balthzar and the severity of illness index according to CT in predicting the development of complications of acute pancreatitis. A retrospective study was performed in 100 patients with clinical and analytical evidence of acute pancreatitis. All patients were assessed according to Ranson score at admission and 48 hours later, and contrast-enhanced abdominal CT was carried out. The tomographic images were analyzed on the basis of the classical criteria of Balthazar and the new CT severity of illness index, which includes the assessment of pancreatic necrosis, identified as the areas of the pancreas that are not enhanced by the administration of the contrast material. These three criteria were then correlated with onset of medical and surgical implications. Our findings show that, of the three criteria analyzed, the CT severity of illness index presents the greatest specificity, sensitivity and positive and negative predictive values in the prediction of complications of acute pancreatitis. We conclude that the inclusion of pancreatic necrosis in the tomographic study improves the early assessment of the prognosis of acute pancreatitis. (Author) 20 refs

  20. Isoattenuating insulinomas at biphasic contrast-enhanced CT: frequency, clinicopathologic features and perfusion characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Liang; Xue, Hua-dan; Sun, Hao; Wang, Xuan; He, Yong-lan; Jin, Zheng-yu [Peking Union Medical College Hospital, Department of Radiology, Beijing (China); Zhao, Yu-pei [Peking Union Medical College Hospital, Department of General Surgery, Beijing (China)

    2016-10-15

    We aimed to determine the frequency of isoattenuating insulinomas, to investigate their clinicopathological features and to assess their regional pancreatic perfusion characteristics. Institutional review board approval was obtained, and patient informed consent was waived. From July 2010 to June 2014, 170 patients (66 male, 104 female) with endogenous hyperinsulinemic hypoglycemia underwent biphasic contrast-enhanced CT before surgery, and 129 of those patients also received preoperative whole-pancreas CT perfusion. A total of 181 tumours were proved histopathologically after surgery. Enhancement pattern and regional pancreatic perfusion characteristics were analyzed. Clinical features, tumour size and pathological grading were investigated. The frequency of isoattenuating tumours was 24.9 %. Tumour size and WHO grading was not significantly different between isoattenuating and hyperattenuating tumours. Tumour-free regions had identical blood flow (BF) regardless of their location (p = 0.35). Isoattenuating tumour-harbouring regions had lower BF compared with hyperattenuating tumour-harbouring regions; both showed higher BF compared with tumour-free neighbourhood regions (all p < 0.01). For patients with isoattenuating tumours, the overall hospital stay was longer (p < 0.01). A substantial subset of insulinomas were isoattenuating on biphasic CT. CT perfusion showed higher BF in tumour-harbouring regions compared to tumour-free regions, providing a clue for tumour regionalization. (orig.)

  1. Predicting tumor hypoxia in non-small cell lung cancer by combining CT, FDG PET and dynamic contrast-enhanced CT.

    Science.gov (United States)

    Even, Aniek J G; Reymen, Bart; La Fontaine, Matthew D; Das, Marco; Jochems, Arthur; Mottaghy, Felix M; Belderbos, José S A; De Ruysscher, Dirk; Lambin, Philippe; van Elmpt, Wouter

    2017-11-01

    Most solid tumors contain inadequately oxygenated (i.e., hypoxic) regions, which tend to be more aggressive and treatment resistant. Hypoxia PET allows visualization of hypoxia and may enable treatment adaptation. However, hypoxia PET imaging is expensive, time-consuming and not widely available. We aimed to predict hypoxia levels in non-small cell lung cancer (NSCLC) using more easily available imaging modalities: FDG-PET/CT and dynamic contrast-enhanced CT (DCE-CT). For 34 NSCLC patients, included in two clinical trials, hypoxia HX4-PET/CT, planning FDG-PET/CT and DCE-CT scans were acquired before radiotherapy. Scans were non-rigidly registered to the planning CT. Tumor blood flow (BF) and blood volume (BV) were calculated by kinetic analysis of DCE-CT images. Within the gross tumor volume, independent clusters, i.e., supervoxels, were created based on FDG-PET/CT. For each supervoxel, tumor-to-background ratios (TBR) were calculated (median SUV/aorta SUV mean ) for HX4-PET/CT and supervoxel features (median, SD, entropy) for the other modalities. Two random forest models (cross-validated: 10 folds, five repeats) were trained to predict the hypoxia TBR; one based on CT, FDG, BF and BV, and one with only CT and FDG features. Patients were split in a training (trial NCT01024829) and independent test set (trial NCT01210378). For each patient, predicted, and observed hypoxic volumes (HV) (TBR > 1.2) were compared. Fifteen patients (3291 supervoxels) were used for training and 19 patients (1502 supervoxels) for testing. The model with all features (RMSE training: 0.19 ± 0.01, test: 0.27) outperformed the model with only CT and FDG-PET features (RMSE training: 0.20 ± 0.01, test: 0.29). All tumors of the test set were correctly classified as normoxic or hypoxic (HV > 1 cm 3 ) by the best performing model. We created a data-driven methodology to predict hypoxia levels and hypoxia spatial patterns using CT, FDG-PET and DCE-CT features in NSCLC. The

  2. Contrast-enhanced CT and MRI findings of atypical hepatic Echinococcus alveolarisinfestation

    International Nuclear Information System (INIS)

    Etlik, Oemer; Arslan, Halil; Harman, Mustafa; Temizoez, Osman; Bay, Ali; Koesem, Mustafa; Dogan, Ekrem

    2005-01-01

    Diagnosis of liver infestation by Echinococcus alveolaris(EA) is based on serological and radiological findings. In this report, we present a 15-year-old girl with atypical hepatic EA infestation showing central punctate calcifications and contrast enhancement on the portal and late phases of CT and MRI. CT showed a hypodense mass involving more than half of the liver with prominent central calcifications. MRI revealed hypointense signal of the infiltrative mass on both T1- and T2-weighted images. Contrast enhancement is a unique finding in hepatic EA infestation that may cause difficulties with diagnosis. MRI may provide invaluable information in the diagnosis of EA infestation of the liver, either by disclosing the infiltrative pattern of infestation without significant effect to vascular structures, or by the signal characteristics. (orig.)

  3. Contrast-enhanced CT and MRI findings of atypical hepatic Echinococcus alveolarisinfestation

    Energy Technology Data Exchange (ETDEWEB)

    Etlik, Oemer; Arslan, Halil; Harman, Mustafa; Temizoez, Osman [Yuzuncu Yil University Faculty of Medicine, Department of Radiology, Van (Turkey); Bay, Ali [Yuzuncu Yil University Faculty of Medicine, Department of Paediatrics, Van (Turkey); Koesem, Mustafa [Yuzuncu Yil University Faculty of Medicine, Department of Pathology, Van (Turkey); Dogan, Ekrem [Yuzuncu Yil University Faculty of Medicine, Department of Internal Medicine, Van (Turkey)

    2005-05-01

    Diagnosis of liver infestation by Echinococcus alveolaris(EA) is based on serological and radiological findings. In this report, we present a 15-year-old girl with atypical hepatic EA infestation showing central punctate calcifications and contrast enhancement on the portal and late phases of CT and MRI. CT showed a hypodense mass involving more than half of the liver with prominent central calcifications. MRI revealed hypointense signal of the infiltrative mass on both T1- and T2-weighted images. Contrast enhancement is a unique finding in hepatic EA infestation that may cause difficulties with diagnosis. MRI may provide invaluable information in the diagnosis of EA infestation of the liver, either by disclosing the infiltrative pattern of infestation without significant effect to vascular structures, or by the signal characteristics. (orig.)

  4. Skeletal metastasis as detected by 18F-FDG PET with negative CT of the PET/CT: Frequency and impact on cancer staging and or management

    Directory of Open Access Journals (Sweden)

    Fatma Ahmed

    2016-10-01

    Full Text Available Objectives: The aim of our study is to assess the frequency of detection of PET positive CT negative skeletal metastases (SM and determine the impact of such detection on staging and/or management in patients who had FDG PET/CT as part of the cancer work up.Methods: We retrospectively reviewed 2000 18F-FDG PET/CT scans of known cancer patients. A log was kept to record cases of suspected SM with or without bone changes from the low-dose non-contrast CT. The presence or absence of SM was evaluated based on available pathological and clinical data. The impact of detection of such lesions on cancer staging and/or management was evaluated by a board certified oncologist.Results: Of the 2000 cases, 18F-FDG PET/CT suggested SM in 146/2000 (7.3%. Of those 146 cases, 105 (72% were positive on both PET and CT. The remaining 41 (28% had PET positive CT negative bone lesions. SM was confirmed in 36/41 (88% PET positive/CT negative cases. This was based on biopsy, imaging or clinical follow-up. The detection of PET positive CT negative SM did not change staging or management in 7/36 (19.4%. However, staging and/or management was affected in 29/36 (80.6%. Conclusions: SM is not uncommon in 18F-FDG PET/CT, as it accounts for 146/2000 (7.3% of cases. PET demonstrated FDG-avid SM without a CT abnormality in at least 36/146 (25%. Patients staging and or management changed in 29/36 (80.5%. We concluded that 18F-FDG PET is sensitive in detection of SM with significant impact on staging & or management. Key words18F-FDG PET/CT, Skeletal metastasis, PET positive, CT negative

  5. Estimation of enhanced cancer risk with 18FDG PET/CT investigations

    International Nuclear Information System (INIS)

    Kaushik, Aruna; Mishra, Anil K.; Sharma, Rajnish; Mondal, Anupam; Dwarakanath, B.S.

    2014-01-01

    18 F-Fluorodeoxyglucose ( 18 FDG) Positron Emission Tomography/Computed Tomography (PET/CT) investigation involves internal administration of 18 FDG and use of CT X-rays for the purpose of obtaining functional and anatomical information of a patient. However, the radiation exposure from undergoing PET/CT investigation may enhance the risk of cancer incidence as per the Linear-No-Threshold (LNT) model. The objective of the present study was to quantify the risk of cancer incidence associated with radiation exposure from 18 FDG PET/CT investigations. The organ doses from internally administered 18 FDG were estimated using OLINDA/EXM Code by performing dynamic PET scans in different regions of the body in a total of forty-nine patients. Organ doses from the CT component were calculated using the software CT-Expo. The associated cancer risk was calculated in terms of life time risk of cancer incidence resulting from a specified dose of ionizing radiation and was expressed in terms of Lifetime Attributable Risk (LAR). LAR values and the organ doses estimated for males and females were used to estimate the lifetime risk of cancer incidence from whole body 18 FDG PET/CT scan. Since from 18 FDG whole body PET/CT investigations, various tissues of the body receive substantially different doses, the site specific risk of cancer incidence was estimated and summed to obtain the total risk. This was compared with the baseline lifetime risk of cancer incidence in Indian population. LAR of cancer incidence was observed to be relatively higher in females as compared to males. The risk estimates ranged from 0.36% to 0.49% for a 20 year old male and 0.58% to 0.79% for a 20 year old female and were observed to be higher in younger ages and decreased with age. 18 FDG whole body PET/CT investigation was observed to be associated with non-negligible radiation risk as compared to the risks associated with other diagnostic modalities. (author)

  6. Enhancement of detectability by the use of coloured illumination for CT display

    International Nuclear Information System (INIS)

    Warren, R.C.; Simpson, J.

    1984-01-01

    A study has been made of the effect of coloured illumination on the detectability of both natural and artificial low-contrast signals immersed in CT noise. Enhancement of detectability relative to white light was found to be related to variations in visual acuity at different wavelengths. These results, together with previously published observations, suggest that an increase of detectability by changing viewing conditions can usually be achieved only at the expense of a reduction in resolution. (author)

  7. Quantitative evaluation in enhancement of pancreas and adjacent vessels during spiral CT

    International Nuclear Information System (INIS)

    Kim, Hyoung Seuk; Shin, Kue Hee; Park, Cheol Min; Cha, Sang Hoon; Chung, Kyoo Byung

    1997-01-01

    To determine by quantitative evaluation of pancreatic and adjacent vascular enhancement during spiral CT, the ideal scan delay for examination of the pancreas. Dual(n=3D90) and triple(n=3D90) phase spiral CT scans of patients whose pancreas showed no pathologic condition were retrospectively evaluated. Dual-phase scans were performed at 43 seconds(early), and 5-6 minutes(delayed) after the injection of 120ml of contrast material at an injection rate of 3ml/sec;triple-phase scans were performed at 25 seconds(arterial),60-65 seconds (portal) and 5-6 minutes (delayed) after the injection of 120-140ml of contrast material at an injection rate of 2-4ml/sec, and ten patients also underwent precontrast scanning. CT attenuation values(HU) were measured in the head, body and tail of the pancreas, aorta, and main portal vein during each phase of all scans. Triple-phase protocol was used to measure the effect of different total volumes and injection rates on enhancement of the pancreas and adjacent vessels. There was no significant difference in the degree of enhancement of the pancreas head, body and tail during each phase(p>0.05). The pancreas was maximally enhanced on 43 second delayed scan(132±20HU)(p 0.05). The main portal vein showed maximum enhancement on 43-second delayed scan(207±44HU)(p<0.05). Different total volume of contrast material did not change the enhancement of the pancreas and adjacent vessels. At an injection rate of 2ml/sec, peak enhancement of the pancreas, aorta and portal vein was obtained on 60-65 second delayed scan, and at 4ml/sec, peak enhancement was obtained on 25 second delayed scan(p<0.05). Observing the usual protocols for abdominal spiral CT scanning, the pancreas was most effectively evaluated using a 43-second delayed scan. An increased injection rate resulted in earlier enhancement of the pancreas, aorta and portal vein

  8. Prospective evaluation of MRI, 11C-acetate PET/CT and contrast-enhanced CT for staging of bladder cancer

    International Nuclear Information System (INIS)

    Vargas, H.A.; Akin, O.; Schöder, H.; Olgac, S.; Dalbagni, G.; Hricak, H.; Bochner, B.H.

    2012-01-01

    Purpose: To prospectively evaluate the diagnostic performance of magnetic resonance imaging (MRI), 11 C-acetate positron emission tomography/computed tomography (PET/CT) and contrast-enhanced CT for bladder cancer staging, using whole-mount pathologic review of radical cystectomy and pelvic lymph node specimens as the reference standard. Materials and methods: The institutional review board approved this prospective study, which was compliant with the Health Insurance Portability and Accountability Act. Written informed consent was obtained from 16 patients with histologically confirmed bladder cancer who underwent MRI, 11 C-acetate PET/CT and contrast-enhanced CT before radical cystectomy and pelvic lymph node dissection. Before imaging 4/16 patients had received intravesical Bacillus Calmette-Guérin treatment, 6 had received systemic chemotherapy, 3 had received both and 3 had received neither. Measures of diagnostic performance including accuracy, sensitivity and specificity were estimated separately for each imaging modality. Results: MRI correctly staged 56% of patients (9/16), overstaged 38% (6/16) and understaged 6% (1/16). CT correctly staged 50% of patients (8/16), overstaged 44% (7/16) and understaged 6% (1/16). In 9 patients, 11 C-acetate PET/CT showed uptake within the bladder wall; the uptake was true-positive in 7 patients and false-positive in 2 patients. Of the remaining 7 patients, 5 had true-negative and 2 had false-negative PET/CT results for cancer in the bladder wall. For all modalities, staging accuracy was reduced in patients with a history of prior intravesical and/or systemic chemotherapy. Conclusion: In staging bladder cancer, MRI, 11 C-acetate PET/CT and CT displayed similar levels of accuracy. For all modalities, a history of intravesical and/or systemic chemotherapy affected staging accuracy.

  9. Prospective evaluation of MRI, {sup 11}C-acetate PET/CT and contrast-enhanced CT for staging of bladder cancer

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, H.A., E-mail: vargasah@mskcc.org [Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Akin, O.; Schöder, H. [Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Olgac, S. [Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Dalbagni, G. [Department of Surgery, Urology Service, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Hricak, H. [Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Bochner, B.H. [Department of Surgery, Urology Service, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

    2012-12-15

    Purpose: To prospectively evaluate the diagnostic performance of magnetic resonance imaging (MRI), {sup 11}C-acetate positron emission tomography/computed tomography (PET/CT) and contrast-enhanced CT for bladder cancer staging, using whole-mount pathologic review of radical cystectomy and pelvic lymph node specimens as the reference standard. Materials and methods: The institutional review board approved this prospective study, which was compliant with the Health Insurance Portability and Accountability Act. Written informed consent was obtained from 16 patients with histologically confirmed bladder cancer who underwent MRI, {sup 11}C-acetate PET/CT and contrast-enhanced CT before radical cystectomy and pelvic lymph node dissection. Before imaging 4/16 patients had received intravesical Bacillus Calmette-Guérin treatment, 6 had received systemic chemotherapy, 3 had received both and 3 had received neither. Measures of diagnostic performance including accuracy, sensitivity and specificity were estimated separately for each imaging modality. Results: MRI correctly staged 56% of patients (9/16), overstaged 38% (6/16) and understaged 6% (1/16). CT correctly staged 50% of patients (8/16), overstaged 44% (7/16) and understaged 6% (1/16). In 9 patients, {sup 11}C-acetate PET/CT showed uptake within the bladder wall; the uptake was true-positive in 7 patients and false-positive in 2 patients. Of the remaining 7 patients, 5 had true-negative and 2 had false-negative PET/CT results for cancer in the bladder wall. For all modalities, staging accuracy was reduced in patients with a history of prior intravesical and/or systemic chemotherapy. Conclusion: In staging bladder cancer, MRI, {sup 11}C-acetate PET/CT and CT displayed similar levels of accuracy. For all modalities, a history of intravesical and/or systemic chemotherapy affected staging accuracy.

  10. Polydopamine-coated gold nanostars for CT imaging and enhanced photothermal therapy of tumors

    Science.gov (United States)

    Li, Du; Shi, Xiangyang; Jin, Dayong

    2016-12-01

    The advancement of biocompatible nanoplatforms with dual functionalities of diagnosis and therapeutics is strongly demanded in biomedicine in recent years. In this work, we report the synthesis and characterization of polydopamine (pD)-coated gold nanostars (Au NSs) for computed tomography (CT) imaging and enhanced photothermal therapy (PTT) of tumors. Au NSs were firstly formed via a seed-mediated growth method and then stabilized with thiolated polyethyleneimine (PEI-SH), followed by deposition of pD on their surface. The formed pD-coated Au NSs (Au-PEI@pD NSs) were well characterized. We show that the Au-PEI@pD NSs are able to convert the absorbed near-infrared laser light into heat, and have strong X-ray attenuation property. Due to the co-existence of Au NSs and the pD, the light to heat conversion efficiency of the NSs can be significantly enhanced. These very interesting properties allow their uses as a powerful theranostic nanoplatform for efficient CT imaging and enhanced phtotothermal therapy of cancer cells in vitro and the xenografted tumor model in vivo. With the easy functionalization nature enabled by the coated pD shell, the developed pD-coated Au NSs may be developed as a versatile nanoplatform for targeted CT imaging and PTT of different types of cancer.

  11. Differences in MRI findings in cases showing ring-enhancement on a CT scan

    International Nuclear Information System (INIS)

    Tokiwa, Kaichi; Hashimoto, Takashi; Miyasaka, Yoshio; Yada, Kenzoh; Kan, Shinichi; Takagi, Hiroshi.

    1990-01-01

    It is sometimes difficult to differentiate between a brain abscess and a tumor, for both show ring-enhancement on a CT scan. The present authors have studied the benefit of MRI for the differential diagnosis of these two lesions. The subjects of this study were 6 cases of brain abscess and 10 cases of brain tumor, all of them showing ring-enhancement on a CT scan. The MRI findings were compared with those of the CT scan taken at almost the same time, especially focussing on the difference in the ring-enhancement. In 5 out of the 6 cases of brain abscess, T 2 -weighted MRI demonstrated a comparatively thin and homogeneous low-intensity, round rim. In the cases of brain tumor, however, none of the cases demonstrated this typical low-intensity, round rim; rather, in them the rim was thick and irregular. The authors can conclude that those MRI findings can serve as important differential diagnostic findings between brain abscess and tumor; also, MRI may be used as a landmark for terminating the administration of antibiotics in cases of brain abscess. (author)

  12. Polymer gel dosimeters with enhanced sensitivity for use in x-ray CT polymer gel dosimetry

    International Nuclear Information System (INIS)

    Jirasek, A; Hilts, M; McAuley, K B

    2010-01-01

    A primary limitation of current x-ray CT polymer gel dosimetry is the low contrast, and hence poor dose resolution, of dose images produced by the system. The low contrast is largely due to the low-dose sensitivity of current formulations of polymer gel for x-ray CT imaging. This study reports on the investigation of new dosimeter formulations with improved dose sensitivity for x-ray CT polymer gel dosimetry. We incorporate an isopropanol co-solvent into an N-isopropylacrylamide-based gel formulation in order to increase the total monomer/crosslinker concentration (%T) within the formulation. It is shown that gels of high %T exhibit enhanced dose sensitivity and dose resolutions over traditional formulations. The gels are shown to be temporally stable and reproducible. A single formulation (16%T) is used to demonstrate the capabilities of the x-ray CT polymer gel dosimetry system in measuring known dose distributions. A 1 L gel volume is exposed to three separate irradiations: a single-field percent depth dose, a two-field 'cross' and a three-field 'test case'. The first two irradiations are used to generate a dose calibration curve by which images are calibrated. The calibrated images are compared with treatment planning predictions and it is shown that the x-ray CT polymer gel dosimetry system is capable of capturing spatial and dose information accurately. The proposed new gel formulation is shown to be sensitive, stable and to improve the dose resolution over current formulations so as to provide a feasible gel for clinical applications of x-ray CT polymer gel dosimetry.

  13. Polymer gel dosimeters with enhanced sensitivity for use in x-ray CT polymer gel dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Jirasek, A [Department of Physics and Astronomy, University of Victoria, Victoria BC V8W 3P6 (Canada); Hilts, M [Medical Physics, BC Cancer Agency-Vancouver Island Centre, Victoria BC V6R 2B6 (Canada); McAuley, K B, E-mail: jirasek@uvic.c [Department of Chemical Engineering, Queens University, Kingston, ON K7 L 3N6 (Canada)

    2010-09-21

    A primary limitation of current x-ray CT polymer gel dosimetry is the low contrast, and hence poor dose resolution, of dose images produced by the system. The low contrast is largely due to the low-dose sensitivity of current formulations of polymer gel for x-ray CT imaging. This study reports on the investigation of new dosimeter formulations with improved dose sensitivity for x-ray CT polymer gel dosimetry. We incorporate an isopropanol co-solvent into an N-isopropylacrylamide-based gel formulation in order to increase the total monomer/crosslinker concentration (%T) within the formulation. It is shown that gels of high %T exhibit enhanced dose sensitivity and dose resolutions over traditional formulations. The gels are shown to be temporally stable and reproducible. A single formulation (16%T) is used to demonstrate the capabilities of the x-ray CT polymer gel dosimetry system in measuring known dose distributions. A 1 L gel volume is exposed to three separate irradiations: a single-field percent depth dose, a two-field 'cross' and a three-field 'test case'. The first two irradiations are used to generate a dose calibration curve by which images are calibrated. The calibrated images are compared with treatment planning predictions and it is shown that the x-ray CT polymer gel dosimetry system is capable of capturing spatial and dose information accurately. The proposed new gel formulation is shown to be sensitive, stable and to improve the dose resolution over current formulations so as to provide a feasible gel for clinical applications of x-ray CT polymer gel dosimetry.

  14. A segmentation and point-matching enhanced efficient deformable image registration method for dose accumulation between HDR CT images

    International Nuclear Information System (INIS)

    Zhen, Xin; Chen, Haibin; Zhou, Linghong; Yan, Hao; Jiang, Steve; Jia, Xun; Gu, Xuejun; Mell, Loren K; Yashar, Catheryn M; Cervino, Laura

    2015-01-01

    Deformable image registration (DIR) of fractional high-dose-rate (HDR) CT images is challenging due to the presence of applicators in the brachytherapy image. Point-to-point correspondence fails because of the undesired deformation vector fields (DVF) propagated from the applicator region (AR) to the surrounding tissues, which can potentially introduce significant DIR errors in dose mapping. This paper proposes a novel segmentation and point-matching enhanced efficient DIR (named SPEED) scheme to facilitate dose accumulation among HDR treatment fractions. In SPEED, a semi-automatic seed point generation approach is developed to obtain the incremented fore/background point sets to feed the random walks algorithm, which is used to segment and remove the AR, leaving empty AR cavities in the HDR CT images. A feature-based ‘thin-plate-spline robust point matching’ algorithm is then employed for AR cavity surface points matching. With the resulting mapping, a DVF defining on each voxel is estimated by B-spline approximation, which serves as the initial DVF for the subsequent Demons-based DIR between the AR-free HDR CT images. The calculated DVF via Demons combined with the initial one serve as the final DVF to map doses between HDR fractions. The segmentation and registration accuracy are quantitatively assessed by nine clinical HDR cases from three gynecological cancer patients. The quantitative analysis and visual inspection of the DIR results indicate that SPEED can suppress the impact of applicator on DIR, and accurately register HDR CT images as well as deform and add interfractional HDR doses. (paper)

  15. A segmentation and point-matching enhanced efficient deformable image registration method for dose accumulation between HDR CT images

    Science.gov (United States)

    Zhen, Xin; Chen, Haibin; Yan, Hao; Zhou, Linghong; Mell, Loren K.; Yashar, Catheryn M.; Jiang, Steve; Jia, Xun; Gu, Xuejun; Cervino, Laura

    2015-04-01

    Deformable image registration (DIR) of fractional high-dose-rate (HDR) CT images is challenging due to the presence of applicators in the brachytherapy image. Point-to-point correspondence fails because of the undesired deformation vector fields (DVF) propagated from the applicator region (AR) to the surrounding tissues, which can potentially introduce significant DIR errors in dose mapping. This paper proposes a novel segmentation and point-matching enhanced efficient DIR (named SPEED) scheme to facilitate dose accumulation among HDR treatment fractions. In SPEED, a semi-automatic seed point generation approach is developed to obtain the incremented fore/background point sets to feed the random walks algorithm, which is used to segment and remove the AR, leaving empty AR cavities in the HDR CT images. A feature-based ‘thin-plate-spline robust point matching’ algorithm is then employed for AR cavity surface points matching. With the resulting mapping, a DVF defining on each voxel is estimated by B-spline approximation, which serves as the initial DVF for the subsequent Demons-based DIR between the AR-free HDR CT images. The calculated DVF via Demons combined with the initial one serve as the final DVF to map doses between HDR fractions. The segmentation and registration accuracy are quantitatively assessed by nine clinical HDR cases from three gynecological cancer patients. The quantitative analysis and visual inspection of the DIR results indicate that SPEED can suppress the impact of applicator on DIR, and accurately register HDR CT images as well as deform and add interfractional HDR doses.

  16. CT enhancement of acute cerebral infarction following long-term continuous contrast infusion

    International Nuclear Information System (INIS)

    Ito, Umeo; Seida, Mitsuru; Tomida, Shuichi; Inaba, Yutaka.

    1985-01-01

    In this experimental study, we employed a long-term (3 hours) continuous-drip infusion of the contrast medium (200 ml of meglumine amidtrizoate) rather than the conventional bolus injection. On admission, four-vessel angiography was performed on all 14 patients. Within 3 days after the onset of the disease, CT scan was carried out repeatedly just prior to contrast infusion, immediately after the end of the continuous-contrast infusion, and additionally, in 4 cases, 3 hours after the end of the contrast infusion. The Haunsfield number was calculated in 3 regions of interest (Radius 5) in the infarction. Positive enhancement was observed in 10 out of the 14 patients (71 %). Among them, 4 out of 5 patients in whom no vascular obstraction on angiography, but marked low-density areas with a mass effect on CT were observed, showed moderate to marked enhancement. In these 4 patients, a temporary cerebral ischemia due to vascular embolization was considered. From the other 4 patients in whom the additional CT scan was performed 3 hours after the end of the contrast infusion, a blood sample was obtained at each of the 3 CT scannings. The iodine concentrations of the blood samples were measured, and their Haunsfield numbers were calculated in the water phantom. The above two parameters were well correlated in a linear function. Among the 4 patients, Gado's tissue-blood ratio (the Haunsfield number of the CT lesion is divided by that of the blood sample) was more than 17.2 % immediately after, and more than 54.7 % 3 hours after, the contrast infusion. Thus, we could conclude that the break-down of the BBB which was demonstrated by a long-term high-blood-concentration level of the contrast medium is an earlier event in human cerebral infarction than is usually accepted. The findings are compatible with our results in animal experiments. (author)

  17. Feasibility of using intravenous contrast-enhanced computed tomography (CT) scans in lung cancer treatment planning

    International Nuclear Information System (INIS)

    Xiao Jianghong; Zhang Hong; Gong Youling; Fu Yuchuan; Tang Bin; Wang Shichao; Jiang Qingfeng; Li Ping

    2010-01-01

    Background and purpose: To investigate the feasibility of using intravenous contrast-enhanced computed tomography (CT) scans in 3-dimensional conformal radiotherapy (3D-CRT), stereotactic body radiation therapy (SBRT) and intensity-modulated radiotherapy (IMRT) treatment planning for lung cancers, respectively. Materials and methods: Twelve patients with bulky lung tumors and 14 patients with small lung tumors were retrospectively analyzed. Each patient took two sets of CT in the same position with active breathing control (ABC) technique before and after intravenous contrast agent (CA) injections. Bulky tumors were planned with 3D-CRT, while SBRT plans were generated for patients with small tumors based on CT scans with intravenous CA. In addition, IMRT plans were generated for patients with bulky tumors to continue on a planning study. All plans were copied and replaced on the scans without intravenous CA. The radiation doses calculated from the two sets of CTs were compared with regard to planning volumes (PTV), the organ at-risk (OAR) and the lungs using Wilcoxon's signed rank test. Results: In comparisons for 3D-CRT plans, CT scans with intravenous CA reduced the mean dose and the maximum dose of PTV with significant differences (p 95 ) for targets, respectively (p < 0.05). There was no statistical significance for lung parameters between two sets of scans in SBRT plans and IMRT plans. Conclusions: The enhanced CT scans can be used for both target delineation and treatment planning in 3D-CRT. The dose difference caused by intravenous CA is small. But for SBRT and IMRT, the minimum irradiation dose in targets may be estimated to be increased up to 2.71% while the maximum dose may be estimated to be decreased up to 1.36%. However, the difference in dose distribution in most cases were found to be clinical tolerable.

  18. Chronic thromboembolic pulmonary hypertension: diagnostic impact of multislice-CT and selective pulmonary-DSA

    International Nuclear Information System (INIS)

    Pitton, M.B.; Kemmerich, G.; Herber, S.; Schweden, F.; Thelen, M.; Mayer, E.

    2002-01-01

    Purpose: To evaluate the diagnostic impact of multislice-CT and selective pulmonary DSA in chronic thromboembolic pulmonary hypertension (CTEPH). Methods: 994 vessel segments of 14 consecutive patients with CTEPH were investigated with multislice-CT (slice thickness 3 mm, collimation 2.5 mm, reconstruction intervall 2 mm) and selective pulmonary DSA posterior-anterior, 45 oblique, and lateral projection. Analysis was performed by 2 investigators independently for CT and DSA. Diagnostic criteria were occlusions and non-occlusive changes like webs and bands, irregularities of the vessel wall, diameter reduction and thromboembolic depositions at different levels from central pulmonary arteries to subsegmental arteries. Reference diagnosis was made by synopsis of CT and DSA by consensus. Results: Concerning patency CT and DSA showed concordant findings overall in 88.9%, 92.9% for segmental arteries and 85.4% for subsegmental arteries. Concerning any thromboembolic changes, multislice-CT was significantly inferior to selective DSA (concordance 67.0% overall, 70.4% for segments and 63.6% for subsegments). Non-occlusive changes of the vessels were significantly underdiagnosed by CT (concordance of CT versus DSA: 23.1%). Conclusion: Multislice-CT and selective pulmonary DSA are equivalent for diagnosis of vessel occlusions at the level of segmental and subsegmental arteries. However, for visualisation of the non-occlusive thromboembolic changes of the vessel wall selective pulmonary DSA is still superior compared to multislice-CT. Multislice-CT and selective pulmonary DSA are complementary tools for diagnosis and treatment planning of chronic thromboembolic pulmonary hypertension (CTEPH). (orig.) [de

  19. 18F-FDG PET/CT Findings Following Repeated Intramuscular Injections of "Site Enhancement Oil" in the Upper Extremities

    DEFF Research Database (Denmark)

    Dejanović, Danijela; Loft, Annika

    2017-01-01

    We present the findings on F-FDG PET/CT in a 50-year-old man known to self-administer intramuscular injections with site enhancement oil in the upper extremities. PET images show diffuse pathological high FDG uptake in soft tissue of the upper arms and in scanned portions of the forearms. On the CT...

  20. Multiphasic contrast-enhanced CT and MRI findings of adult mesoblastic nephroma: A report of two cases

    Directory of Open Access Journals (Sweden)

    Yuqin Ding

    2013-01-01

    Full Text Available Mesoblastic nephroma (MN presenting in an adult is extremely rare. The computed tomography (CT and magnetic resonance imaging (MRI features of this tumor in adulthood have not been widely reported. We present two additional cases of adult MN and describe the multiphasic contrast-enhanced CT and MRI findings.

  1. Phase- and size-adjusted CT cut-off for differentiating neoplastic lesions from normal colon in contrast-enhanced CT colonography

    International Nuclear Information System (INIS)

    Luboldt, W.; Kroll, M.; Wetter, A.; Vogl, T.J.; Toussaint, T.L.; Hoepffner, N.; Holzer, K.; Kluge, A.

    2004-01-01

    A computed tomography (CT) cut-off for differentiating neoplastic lesions (polyps/carcinoma) from normal colon in contrast-enhanced CT colonography (CTC) relating to the contrast phase and lesion size is determined. CT values of 64 colonic lesions (27 polyps 0 . The slope m was determined by linear regression in the correlation (lesion ∝[xA + (1 - x)V]//H) and the Y-intercept y 0 by the minimal shift of the line needed to maximize the accuracy of separating the colonic wall from the lesions. The CT value of the lesions correlated best with the intermediate phase: 0.4A+ 0.6V(r=0.8 for polyps ≥10 mm, r=0.6 for carcinomas, r=0.4 for polyps <10 mm). The accuracy in the differentiation between lesions and normal colonic wall increased with the height implemented as divisor, reached 91% and was obtained by the dynamic cut-off described by the formula: cut-off(A,V,H) = 1.1[0.4A + 0.6V]/H + 69.8. The CT value of colonic polyps or carcinomas can be increased extrinsically by scanning in the phase in which 0.4A + 0.6V reaches its maximum. Differentiating lesions from normal colon based on CT values is possible in contrast-enhanced CTC and improves when the cut-off is adjusted (normalized) to the contrast phase and lesion size. (orig.)

  2. Benign pulmonary nodule. Morphological features and contrast enhancement evaluated with contiguous thin-section CT

    Energy Technology Data Exchange (ETDEWEB)

    Matsuo, Hisayasu; Murata, Kiyoshi; Takahashi, Masashi; Morita, Rikushi [Shiga Univ. of Medical Science, Otsu (Japan)

    1998-10-01

    The morphological changes in 54 benign lung nodules, including 8 histologically proven nodules of tuberculoma, 10 of focal organizing pneumonia (FOP), 1 of lung abscess and 35 other benign nodules, were evaluated with contiguous thin-section (3 mm) CT. In addition, incremental dynamic studies were carried out in 25 of these nodules. The three-dimensional shapes of the nodules were found to be quite varied and were classified into four types: round mass (n=18), polygonal mass with concave or straight margins (n=20), oval or band-like mass extending along the bronchovascular bundle (n=7), and oval mass attached to the pleura with broad contact (n=9). Forty-two (78%) of the 54 nodules were located along the bronchovascular bundle. The maximum increments in CT values over 20 HU were observed after contrast enhancement in 18 (72%) of the 25 benign nodules, among which all tuberculomas showed little or no contrast enhancement. The number of small vessels quantified microscopically in the center of the nodules were minimal in tuberculomas with little enhancement and plentiful in lesions of FOP and abscess which showed marked enhancement. Our results suggest that the differentiation between benign and malignant pulmonary nodules is not possible simply on the basis of the degree of contrast enhancement. Therefore, morphological features and the anatomical relation to the bronchovascular bundles should also be taken into consideration in the diagnosis of pulmonary nodules. (author)

  3. Benign pulmonary nodule. Morphological features and contrast enhancement evaluated with contiguous thin-section CT

    International Nuclear Information System (INIS)

    Matsuo, Hisayasu; Murata, Kiyoshi; Takahashi, Masashi; Morita, Rikushi

    1998-01-01

    The morphological changes in 54 benign lung nodules, including 8 histologically proven nodules of tuberculoma, 10 of focal organizing pneumonia (FOP), 1 of lung abscess and 35 other benign nodules, were evaluated with contiguous thin-section (3 mm) CT. In addition, incremental dynamic studies were carried out in 25 of these nodules. The three-dimensional shapes of the nodules were found to be quite varied and were classified into four types: round mass (n=18), polygonal mass with concave or straight margins (n=20), oval or band-like mass extending along the bronchovascular bundle (n=7), and oval mass attached to the pleura with broad contact (n=9). Forty-two (78%) of the 54 nodules were located along the bronchovascular bundle. The maximum increments in CT values over 20 HU were observed after contrast enhancement in 18 (72%) of the 25 benign nodules, among which all tuberculomas showed little or no contrast enhancement. The number of small vessels quantified microscopically in the center of the nodules were minimal in tuberculomas with little enhancement and plentiful in lesions of FOP and abscess which showed marked enhancement. Our results suggest that the differentiation between benign and malignant pulmonary nodules is not possible simply on the basis of the degree of contrast enhancement. Therefore, morphological features and the anatomical relation to the bronchovascular bundles should also be taken into consideration in the diagnosis of pulmonary nodules. (author)

  4. Examination of hepatic contrast-enhanced CT monitored by Smart Prep

    International Nuclear Information System (INIS)

    Kakizaki, Dai; Saito, Kazuhiro; Sakurada, Toru; Abe, Kimihiko; Suzuki, Kenji

    1999-01-01

    The aim of the present study is to obtain the time density curves of the contrast-enhanced CT of hepatic portal vein, hepatic and splenic parenchyma, and to examine the relation with age, body weight, type of liver dysfunction. Subjects were 32 patients with liver tumors or liver diseases. For this purpose, the procedure of hepatic CT was monitored by Smart Prep and the images of whole liver was taken when the level of the contrast at the hepatic portal vein reached to the enhancement threshold. The contrast medium used was Iomeprol 300. The adverse reactions by Iomeprol 300 were mild and any treatment did not need. There was no correlation age and weight with enhancement threshold at the hepatic portal vein and peak time at the splenic parenchyma. The enhancement threshold at the hepatic portal vein was various in patients with chrrhosis and chronic hepatitis, and tended to be delayed in patients with chrrhosis. The peak time of the splenic parenchyma was up to 52 seconds in all patients with chronic hepatitis. The shortage of the enhancement threshold and the increase in blood flow at arterial early phase were observed in the patients with advanced acute hepatitis. This method should be examined more cases with various hepatic diseases. (K.H.)

  5. Persistent adrenal enhancement may be the earliest CT sign of significant hypovolaemic shock

    Energy Technology Data Exchange (ETDEWEB)

    Cheung, S.C.W.; Lee, R.; Tung, H.K.S.; Chan, F.L

    2003-04-01

    AIM: To report two cases of intense and persistent adrenal enhancement on computed tomography (CT) examinations of the abdomen. MATERIALS AND METHODS: Two patients presented with septic shock, one due to pyogenic liver abscess and the other strangulated obturator hernia with gangrenous bowel. Both patients were resuscitated with fluid before undergoing unenhanced and enhanced CT. RESULTS: In both patients intravascular volume was not reduced as evident by normal calibre of the aorta and inferior vena cava. One patient had abnormal enhancement pattern in the liver and kidneys, suggesting hypoperfusion. The other patient had normal enhancement pattern of the other abdominal viscera. Both patient subsequently died with multi-organ failure. CONCLUSION: We propose that adrenal enhancement may be a sign of hyperperfusion in early stage of shock due to the crucial role of the adrenal glands in this clinical situation. This may not persist with further circulatory compromise due to vasoconstriction. If confirmed, its recognition has potential value of identifying a therapeutic window before irreversible shock set in.

  6. Diagnostic impact of SPECT-CT in the assessment of endocrine tumors

    International Nuclear Information System (INIS)

    El Badaoui, A.; Clermont, H. de; Valli, N.; Caignon, J.M.; Fernandez, P.; Allard, M.; Barat, J.L.; Ducassou, D.; Clermont, H. de; Valli, N.; Caignon, J.M.; Fernandez, P.; Allard, M.; Barat, J.L.; Ducassou, D.; Clermont, H. de; Allard, M.

    2008-01-01

    Image fusion using single photon emission computed tomography - computed tomography (SPECT - CT) associates functional and morphological images. This study evaluates the added value of SPECT- CT, obtained with a hybrid SPECT- CT gamma camera, on anatomic localization and diagnostic impact in assessment of endocrine tumours and pheochromocytomas. Method: Six months prospective study was undertaken including 33 consecutive exams encompassing 20 Somatostatin Receptor Scintigraphies (S.R.S.) and 13 123 I-meta-iodo-benzyl-guanidine (Mibg) scans. Two experienced nuclear medicine physicians independently analysed independently planar and SPECT images in a first time, then, SPECT- CT fused images in a second time. They evaluated two parameters: SPECT- CT impact on anatomic localization (L.A.) and its diagnostic impact (I.D.). Each parameter was scored according three levels of evaluation. Results: An added value of SPECT- CT images was evidenced in 55% of cases on the anatomic localization and in 41% of the patients on the diagnostic impact. Therefore, a more important benefit was noted when SPECT was positive (L.A.: 90%; I.D.: 70%) than when it was negative (L.A.: 15%; I.D.: 8%). Furthermore, the added value proved higher for the S;R.S. compared to Mibg scans. Conclusion: SPECT- CT fusion images obtained by a hybrid system is more relevant to determine anatomic localization and more accurate than SPECT alone, particularly in the assessment of endocrine tumours. The added value of SPECT- CT seems to be lower for Mibg scans in the assessment of pheochromocytomas. (authors)

  7. Dynamic contrast-enhanced MR imaging in osteoid osteoma: relationships with clinical and CT characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Pottecher, P. [Hopital Lariboisiere, AP-HP, Department of Osteoarticular Radiology, Paris (France); Hopital du Bocage, Department of Vascular, Oncologic and Interventional Radiology, Dijon (France); Sibileau, E.; Hamze, B.; Parlier, C.; Laredo, J.D.; Bousson, V. [Hopital Lariboisiere, AP-HP, Department of Osteoarticular Radiology, Paris (France); Aho, S. [Hopital du Bocage, Hospital Hygiene and Epidemiology unit, Dijon (France)

    2017-07-15

    To correlate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) features to clinical and computed tomography (CT) morphological features of osteoid osteoma (OO). Our institutional review board approved this retrospective study, waiving the need for informed consent. We included the 102 patients treated with interstitial laser ablation for histologically documented OO at our institution in 2008-2013. DCE-MRI variables were the time-enhancement pattern and rising slope (Slope{sub rise}) and CT variables were the bone and segment involved (OO{sub bone} and OO{sub segment,} respectively), OO location relative to the native cortex (OO{sub cortex}), nidus surface area, vessel sign, and largest neighboring-vessel diameter (Dmax{sub vessel}). Descriptive statistics and correlations linking DCE-MRI findings to clinical and CT characteristics were computed. DCE-MRI showed early arterial peak enhancement in 95 (93%) cases, with a mean Slope{sub rise} of 9.30 ± 8.10. CT visualized a vessel sign in 84 (82%) cases with a mean Dmax{sub vessel} of 1.10 ± 0.60 mm. By univariate analysis, Slope{sub rise} correlated significantly with pain duration and Dmax{sub vessel} (r = 0.30, P = 0.003; and r = 0.22, P = 0.03; respectively). Analysis of variance showed that Slope{sub rise} correlated significantly with OO{sub bone} (P < 0.001), with a steeper slope for OOs located in short or flat bones. This study suggests more abundant vascularization of OOs with long-lasting pain and location on short or flat bones. (orig.)

  8. Does Enhancement or Perfusion on Preprocedure CT Predict Outcomes After Embolization of Hepatocellular Carcinoma?

    Science.gov (United States)

    Borgheresi, Alessandra; Gonzalez-Aguirre, Adrian; Brown, Karen T; Getrajdman, George I; Erinjeri, Joseph P; Covey, Anne; Yarmohammadi, Hooman; Ziv, Etay; Sofocleous, Constantinos T; Boas, Franz Edward

    2018-03-27

    The objective of this study was to evaluate whether quantitative enhancement or perfusion measurements on preprocedure triphasic computed tomography (CT) can be used to predict response or overall survival after embolization of hepatocellular carcinoma. The institutional review board approved this retrospective review of 63 patients with hepatocellular carcinoma treated with particle embolization between March 2009 and December 2014. Quantitative enhancement and perfusion measurements were performed on the target tumor and the background liver on the triphasic CT performed before treatment. Microvascular invasion (MVI) and degree of differentiation were determined from a core biopsy specimen. Quantitative enhancement and perfusion values were then correlated with pathology (two-tailed t test), response to embolization on modified Response Evaluation Criteria In Solid Tumors (two-tailed t test), and overall survival after embolization (Cox proportional hazards model). Arterial enhancement did not predict immediate response or overall survival after embolization. The degree of differentiation or presence of MVI also did not predict immediate response or overall survival after embolization. However, high hepatic artery coefficient or low portal vein coefficient, both in the tumor (P = .011 and P = .004) and in the background liver (P = .015 and P = .009), were associated with worse survival. Hepatic artery coefficient, both in the tumor (P = .025) and in the background liver (P = .013), were independent predictors of survival in a multivariate model including the Child-Pugh score and the BCLC stage. Tumor and liver perfusion parameters estimated from preprocedure triphasic CT were predictive of survival after embolization. Arterial-phase enhancement and histology (degree of differentiation or MVI) did not predict immediate response or overall survival after particle embolization. Copyright © 2018 The Association of University Radiologists

  9. Impact of 18F-FDG-PET/CT on staging and irradiation of patients with locally advanced rectal cancer

    International Nuclear Information System (INIS)

    Paskeviciute, Brigita; Boelling, Tobias; Brinkmann, Markus; Rudykina, Ganna; Ernst, Iris; Willich, Normann; Koenemann, Stefan; Stegger, Lars; Schober, Otmar; Weckesser, Matthias

    2009-01-01

    To investigate the impact of fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) on planning of neoadjuvant radiotherapy for locally advanced rectal cancer (LARC) patients. From January 2003 to December 2007, a total of 36 patients with LARC underwent a retroprospective PET/CT study for radiotherapy-planning purposes. Gross tumor volume (GTV), clinical target volume (CTV) and planning target volume (PTV) were defined in a retrospective analysis by a blinded reader. The hypothetical boost volume was defined primarily on CT alone, and afterwards on the fused PET/CT dataset. The CT- and PET/CT-based GTVs were quantitatively compared and percentage of overlap (OV%) was calculated and analyzed. The impact of PET/CT on radiation treatment planning and overall patient management was evaluated. PET/CT-GTVs were smaller than CT-GTVs (p < 0.05). PET/CT imaging resulted in a change of overall management for three patients (8 %). In 16 of 35 patients (46 %), PET/CT resulted in a need for modification of the usual target volumes (CT-PTV) because of detection of a geographic miss. FDG-PET/CT had significant impact on radiotherapy planning and overall treatment of patients with LARC. (orig.)

  10. Quantifying the impact of respiratory-gated 4D CT acquisition on thoracic image quality : a digital phantom study

    NARCIS (Netherlands)

    Bernatowicz, K; Keall, P; Mishra, P; Knopf, A; Lomax, A; Kipritidis, J

    PURPOSE: Prospective respiratory-gated 4D CT has been shown to reduce tumor image artifacts by up to 50% compared to conventional 4D CT. However, to date no studies have quantified the impact of gated 4D CT on normal lung tissue imaging, which is important in performing dose calculations based on

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

    OpenAIRE

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

    2011-01-01

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

  12. Multimodality functional imaging of spontaneous canine tumors using 64Cu-ATSM and 18FDG PET/CT and dynamic contrast enhanced perfusion CT

    International Nuclear Information System (INIS)

    Hansen, Anders E.; Kristensen, Annemarie T.; Law, Ian; McEvoy, Fintan J.; Kjær, Andreas; Engelholm, Svend A.

    2012-01-01

    Purpose: To compare the distribution and uptake of the hypoxia tracer 64 Cu-diacetyl-bis(N 4 -methylthiosemicarbazone) ( 64 Cu-ATSM) PET/CT, FDG PET/CT and dynamic contrast enhanced perfusion CT (DCE-pCT) in spontaneous canine tumors. In addition 64 Cu-ATSM distribution over time was evaluated. Methods and materials: Nine spontaneous cancer-bearing dogs were prospectively enrolled. FDG (1 h pi.) and 64 Cu-ATSM (3 and 24 h pi.) PET/CT were performed over three consecutive days. DCE-pCT was performed on day 2. Tumor uptake of FDG and 64 Cu-ATSM was assessed semi-quantitatively and the distribution of FDG, 64 Cu-ATSM and CT perfusion parameters correlated. Results: 64 Cu-ATSM distribution on scans performed 24 h apart displayed moderate to strong correlation; however, temporal changes were observed. The spatial distribution pattern of 64 Cu-ATSM between scans was moderately to strongly positively correlated to FDG, whereas the correlation of CT perfusion parameters to FDG and to 64 Cu-ATSM yielded more varying results. Conclusions: 64 Cu-ATSM uptake was positively correlated to FDG. 64 Cu-ATSM was found to be relatively stable between PET scans performed at different time points, important temporal changes were however observed in hypo-perfused regions. These findings potentially indicate that prolonged uptake periods for 64 Cu-ATSM imaging may be needed. Although a moderate to strong correlation between 64 Cu-ATSM and FDG PET/CT is observed, the two tracers provide different biological information with an overlapping spatial distribution.

  13. Tin-filter enhanced dual-energy-CT: image quality and accuracy of CT numbers in virtual noncontrast imaging.

    Science.gov (United States)

    Kaufmann, Sascha; Sauter, Alexander; Spira, Daniel; Gatidis, Sergios; Ketelsen, Dominik; Heuschmid, Martin; Claussen, Claus D; Thomas, Christoph

    2013-05-01

    To measure and compare the objective image quality of true noncontrast (TNC) images with virtual noncontrast (VNC) images acquired by tin-filter-enhanced, dual-source, dual-energy computed tomography (DECT) of upper abdomen. Sixty-three patients received unenhanced abdominal CT and enhanced abdominal DECT (100/140 kV with tin filter) in portal-venous phase. VNC images were calculated from the DECT datasets using commercially available software. The mean attenuation of relevant tissues and image quality were compared between the TNC and VNC images. Image quality was rated objectively by measuring image noise and the sharpness of object edges using custom-designed software. Measurements were compared using Student two-tailed t-test. Correlation coefficients for tissue attenuation measurements between TNC and VNC were calculated and the relative deviations were illustrated using Bland-Altman plots. Mean attenuation differences between TNC and VNC (HUTNC - HUVNC) image sets were as follows: right liver lobe -4.94 Hounsfield units (HU), left liver lobe -3.29 HU, vena cava -2.19 HU, spleen -7.46 HU, pancreas 1.29 HU, fat -11.14 HU, aorta 1.29 HU, bone marrow 36.83 HU (all P VNC and TNC series were observed for liver, vena portae, kidneys, pancreas, muscle and bone marrow (Pearson's correlation coefficient ≥0.75). Mean image noise was significantly higher in TNC images (P VNC and TNC images (P = .19). The Hounsfield units in VNC images closely resemble TNC images in the majority of the organs of the upper abdomen (kidneys, liver, pancreas). In spleen and fat, Hounsfield numbers in VNC images are tend to be higher than in TNC images. VNC images show a low image noise and satisfactory edge sharpness. Other criteria of image quality and the depiction of certain lesions need to be evaluated additionally. Copyright © 2013 AUR. Published by Elsevier Inc. All rights reserved.

  14. Development of a dynamic flow imaging phantom for dynamic contrast-enhanced CT

    International Nuclear Information System (INIS)

    Driscoll, B.; Keller, H.; Coolens, C.

    2011-01-01

    Purpose: Dynamic contrast enhanced CT (DCE-CT) studies with modeling of blood flow and tissue perfusion are becoming more prevalent in the clinic, with advances in wide volume CT scanners allowing the imaging of an entire organ with sub-second image frequency and sub-millimeter accuracy. Wide-spread implementation of perfusion DCE-CT, however, is pending fundamental validation of the quantitative parameters that result from dynamic contrast imaging and perfusion modeling. Therefore, the goal of this work was to design and construct a novel dynamic flow imaging phantom capable of producing typical clinical time-attenuation curves (TACs) with the purpose of developing a framework for the quantification and validation of DCE-CT measurements and kinetic modeling under realistic flow conditions. Methods: The phantom is based on a simple two-compartment model and was printed using a 3D printer. Initial analysis of the phantom involved simple flow measurements and progressed to DCE-CT experiments in order to test the phantoms range and reproducibility. The phantom was then utilized to generate realistic input TACs. A phantom prediction model was developed to compute the input and output TACs based on a given set of five experimental (control) parameters: pump flow rate, injection pump flow rate, injection contrast concentration, and both control valve positions. The prediction model is then inversely applied to determine the control parameters necessary to generate a set of desired input and output TACs. A protocol was developed and performed using the phantom to investigate image noise, partial volume effects and CT number accuracy under realistic flow conditionsResults: This phantom and its surrounding flow system are capable of creating a wide range of physiologically relevant TACs, which are reproducible with minimal error between experiments (σ/μ 2 ) for the input function between 0.95 and 0.98, while the maximum enhancement differed by no more than 3.3%. The

  15. Bosniak classification system: a prospective comparison of CT, contrast-enhanced US, and MR for categorizing complex renal cystic masses.

    Science.gov (United States)

    Graumann, Ole; Osther, Susanne Sloth; Karstoft, Jens; Hørlyck, Arne; Osther, Palle Jörn Sloth

    2016-11-01

    Background The Bosniak classification was originally based on computed tomographic (CT) findings. Magnetic resonance (MR) and contrast-enhanced ultrasonography (CEUS) imaging may demonstrate findings that are not depicted at CT, and there may not always be a clear correlation between the findings at MR and CEUS imaging and those at CT. Purpose To compare diagnostic accuracy of MR, CEUS, and CT when categorizing complex renal cystic masses according to the Bosniak classification. Material and Methods From February 2011 to June 2012, 46 complex renal cysts were prospectively evaluated by three readers. Each mass was categorized according to the Bosniak classification and CT was chosen as gold standard. Kappa was calculated for diagnostic accuracy and data was compared with pathological results. Results CT images found 27 BII, six BIIF, seven BIII, and six BIV. Forty-three cysts could be characterized by CEUS, 79% were in agreement with CT (κ = 0.86). Five BII lesions were upgraded to BIIF and four lesions were categorized lower with CEUS. Forty-one lesions were examined with MR; 78% were in agreement with CT (κ = 0.91). Three BII lesions were upgraded to BIIF and six lesions were categorized one category lower. Pathologic correlation in six lesions revealed four malignant and two benign lesions. Conclusion CEUS and MR both up- and downgraded renal cysts compared to CT, and until these non-radiation modalities have been refined and adjusted, CT should remain the gold standard of the Bosniak classification.

  16. The diagnostic value of contrast-enhanced CT in Acute bilateral renal cortical necrosis: a case report

    International Nuclear Information System (INIS)

    Choi, Pil Youb; Lee, Su Han; Lee, Woo Dong

    1996-01-01

    Acute renal cortical necrosis in which there is destruction of the renal cortex and sparing of the renal medulla, is a relatively rare cause of acute renal failure. A definitive diagnosis of acute renal cortical necrosis is based on renal biopsy, but on CT(computed tomography) the rather specific contrast-enhanced appearance of acute renal cortical necrosis has been described. As renal biopsy is not available, contrast-enhanced CT is a useful, noninvasive investigate modality for the early diagnosis of acute renal cortical necrosis. We report the characteristic CT findings of acute renal cortical necrosis in a patient with acute renal failure following an operation for abdominal trauma

  17. Assessing Tumor Response to Treatment in Patients with Lung Cancer Using Dynamic Contrast-Enhanced CT

    DEFF Research Database (Denmark)

    Strauch, Louise S; Eriksen, Rie Ø; Sandgaard, Michael

    2016-01-01

    Reviews and Meta-Analyses (PRISMA) guidelines. Only original research articles concerning treatment response in patients with lung cancer assessed with DCE-CT were included. To assess the validity of each study we implemented Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2). The initial search......The aim of this study was to provide an overview of the literature available on dynamic contrast-enhanced computed tomography (DCE-CT) as a tool to evaluate treatment response in patients with lung cancer. This systematic review was compiled according to Preferred Reporting Items for Systematic...... yielded 651 publications, and 16 articles were included in this study. The articles were divided into groups of treatment. In studies where patients were treated with systemic chemotherapy with or without anti-angiogenic drugs, four out of the seven studies found a significant decrease in permeability...

  18. Effect of contrast enhancement and its indication for CT studies in geriatric patients

    International Nuclear Information System (INIS)

    Yamada, Hideo

    1979-01-01

    Contrast enhancement CT study after drip infusion of 3 ml of 30% Conray for 15 min proved a safe and effective procedure even in geriatric patients with an avarage age of 72.4 years old. Mild untoward effect by contrast agent was observed in 2.5% of cases examined. Contrast study was considered not necessarily to be needed in cases with cerebral infarction showing well defined low density lesion and for evaluation of degree of ventricle enlargement, cerebral atrophy and so forth. On the contrary, contrast infusion study is indispensable in such cases that show mass effect or edema which is frequently observed in fresh cerebral infarction, haemorrhagic infarction, bleeding or tumor. CT studies of the abdomen and thorax were also discussed. (author)

  19. Automated Detection of Healthy and Diseased Aortae from Images Obtained by Contrast-Enhanced CT Scan

    Directory of Open Access Journals (Sweden)

    Michael Gayhart

    2013-01-01

    Full Text Available Purpose. We developed the next stage of our computer assisted diagnosis (CAD system to aid radiologists in evaluating CT images for aortic disease by removing innocuous images and highlighting signs of aortic disease. Materials and Methods. Segmented data of patient’s contrast-enhanced CT scan was analyzed for aortic dissection and penetrating aortic ulcer (PAU. Aortic dissection was detected by checking for an abnormal shape of the aorta using edge oriented methods. PAU was recognized through abnormally high intensities with interest point operators. Results. The aortic dissection detection process had a sensitivity of 0.8218 and a specificity of 0.9907. The PAU detection process scored a sensitivity of 0.7587 and a specificity of 0.9700. Conclusion. The aortic dissection detection process and the PAU detection process were successful in removing innocuous images, but additional methods are necessary for improving recognition of images with aortic disease.

  20. Comparison of 68Ga-DOTANOC PET/CT and contrast-enhanced CT in localisation of tumours in ectopic ACTH syndrome

    Science.gov (United States)

    Jadhav, Swati S; Lila, Anurag R; Kasaliwal, Rajeev; Khare, Shruti; Yerawar, Chaitanya G; Hira, Priya; Phadke, Uday; Shah, Hina; Lele, Vikram R; Malhotra, Gaurav; Bandgar, Tushar; Shah, Nalini S

    2016-01-01

    Background Localising ectopic adrenocorticotrophic hormone (ACTH) syndrome (EAS) tumour source is challenging. Somatostatin receptor-based PET imaging has shown promising results, but the data is limited to case reports and small case series. We reviewed here the performance of 68Ga-DOTANOC positron emission tomography (PET)/computed tomography (CT) and contrast-enhanced CT (CECT) in our cohort of 12 consecutive EAS patients. Materials and methods Retrospective data analysis of 12 consecutive patients of EAS presenting to a single tertiary care centre in a period between January 2013 and December 2014 was done. CECT and 68Ga-DOTANOC PET/CT were reported (blinded) by an experienced radiologist and a nuclear medicine physician, respectively. The performance of CECT and 68Ga-DOTANOC PET/CT was compared. Results Tumours could be localised in 11 out of 12 patients at initial presentation (overt cases), whereas in one patient, tumour remained occult. Thirteen lesions were identified in 11 patients as EAS source (true positives). CECT localised 12 out of these 13 lesions (sensitivity 92.3%) and identified five false-positive lesions (positive predictive value (PPV) 70.5%). Compared with false-positive lesions, true-positive lesions had greater mean contrast enhancement at 60s (33.2 vs 5.6 Hounsfield units (HU)). 68Ga-DOTANOC PET/CT was able to identify 9 out of 13 lesions (sensitivity 69.2%) and reported no false-positive lesions (PPV 100%). Conclusion CECT remains the first-line investigation in localisation of EAS. The contrast enhancement pattern on CECT can further aid in characterisation of the lesions. 68Ga-DOTANOC PET/CT can be added to CECT, to enhance positive prediction of the suggestive lesions. PMID:27006371

  1. Ventilation imaging of the paranasal sinuses using xenon-enhanced dynamic single-energy CT and dual-energy CT: a feasibility study in a nasal cast

    Energy Technology Data Exchange (ETDEWEB)

    Thieme, Sven F.; Helck, Andreas D.; Reiser, Maximilian F.; Johnson, Thorsten R.C. [Ludwig Maximilians University Hospital Munich, Institute for Clinical Radiology, Munich (Germany); Moeller, Winfried; Eickelberg, Oliver [Institute for Lung Biology and Disease (iLBD) and Comprehensive Pneumology Center (CPC), Helmholtz Zentrum Muenchen, Neuherberg, Munich (Germany); Becker, Sven [Ludwig-Maximilians-Universitaet, Department of Otorhinolaryngology - Head and Neck Surgery, Munich (Germany); Schuschnig, Uwe [Pari Pharma GmbH, Graefelfing (Germany)

    2012-10-15

    To show the feasibility of dual-energy CT (DECT) and dynamic CT for ventilation imaging of the paranasal sinuses in a nasal cast. In a first trial, xenon gas was administered to a nasal cast with a laminar flow of 7 L/min. Dynamic CT acquisitions of the nasal cavity and the sinuses were performed. This procedure was repeated with pulsating xenon flow. Local xenon concentrations in the different compartments of the model were determined on the basis of the enhancement levels. In a second trial, DECT measurements were performed both during laminar and pulsating xenon administration and the xenon concentrations were quantified directly. Neither with dynamic CT nor DECT could xenon-related enhancement be detected in the sinuses during laminar airflow. Using pulsating flow, dynamic imaging showed a xenon wash-in and wash-out in the sinuses that followed a mono-exponential function with time constants of a few seconds. Accordingly, DECT revealed xenon enhancement in the sinuses only after pulsating xenon administration. The feasibility of xenon-enhanced DECT for ventilation imaging was proven in a nasal cast. The superiority of pulsating gas flow for the administration of gas or aerosolised drugs to the paranasal sinuses was demonstrated. (orig.)

  2. Solitary pulmonary nodules: Comparison of dynamic first-pass contrast-enhanced perfusion area-detector CT, dynamic first-pass contrast-enhanced MR imaging, and FDG PET/CT.

    Science.gov (United States)

    Ohno, Yoshiharu; Nishio, Mizuho; Koyama, Hisanobu; Seki, Shinichiro; Tsubakimoto, Maho; Fujisawa, Yasuko; Yoshikawa, Takeshi; Matsumoto, Sumiaki; Sugimura, Kazuro

    2015-02-01

    To prospectively compare the capabilities of dynamic perfusion area-detector computed tomography (CT), dynamic magnetic resonance (MR) imaging, and positron emission tomography (PET) combined with CT (PET/CT) with use of fluorine 18 fluorodeoxyglucose (FDG) for the diagnosis of solitary pulmonary nodules. The institutional review board approved this study, and written informed consent was obtained from each subject. A total of 198 consecutive patients with 218 nodules prospectively underwent dynamic perfusion area-detector CT, dynamic MR imaging, FDG PET/CT, and microbacterial and/or pathologic examinations. Nodules were classified into three groups: malignant nodules (n = 133) and benign nodules with low (n = 53) or high (n = 32) biologic activity. Total perfusion was determined with dual-input maximum slope models at area-detector CT, maximum and slope of enhancement ratio at MR imaging, and maximum standardized uptake value (SUVmax) at PET/CT. Next, all indexes for malignant and benign nodules were compared with the Tukey honest significant difference test. Then, receiver operating characteristic analysis was performed for each index. Finally, sensitivity, specificity, and accuracy were compared with the McNemar test. All indexes showed significant differences between malignant nodules and benign nodules with low biologic activity (P Dynamic perfusion area-detector CT is more specific and accurate than dynamic MR imaging and FDG PET/CT in the diagnosis of solitary pulmonary nodules in routine clinical practice. © RSNA, 2014.

  3. Contrast enhancement of focal hepatic lesions in CT: effect of size and histology

    International Nuclear Information System (INIS)

    Burgener, F.A.; Hamlin, D.J.

    1983-01-01

    The effect of size and histology on the contrast enhancement of hepatic lesions has been analyzed in this clinical and experimental investigation yielding the following results: (1) The attenuation values of hepatic cysts in patients increase significantly and inversely with their size after contrast enhancement when the cysts measure less than twice the CT-slice thickness. This seems to be caused by partial-volume effect. (2) Experimental tumors of identical sizes and originating from the same cell line can demonstrate different contrast-enhancement patterns. (3) Peak contrast uptake in both experimental and human tumors seems to be inversely related to their size. (4) Compared to liver, contrast washout from experimental and human tumors (presumably the extravascular space) is delayed. The delay in the contrast washout from a tumor seems to correlate with tumor size. These findings suggest that in general, it is not possible to differentiate reliably among various hepatic neoplasms on the basis of their contrast enhancement patterns for the following reasons: (1) Attenuation values of small hepatic neoplasms are distorted by partial volume effect. (2) Tumors of different histologies can demonstrate the same enhancement pattern. (3) Tumors of identical histology and size can demonstrate different enhancement patterns. (4) The enhancement pattern of a tumor changes with growth or size

  4. Vessel Enhancement and Segmentation of 4D CT Lung Image Using Stick Tensor Voting

    Science.gov (United States)

    Cong, Tan; Hao, Yang; Jingli, Shi; Xuan, Yang

    2016-12-01

    Vessel enhancement and segmentation plays a significant role in medical image analysis. This paper proposes a novel vessel enhancement and segmentation method for 4D CT lung image using stick tensor voting algorithm, which focuses on addressing the vessel distortion issue of vessel enhancement diffusion (VED) method. Furthermore, the enhanced results are easily segmented using level-set segmentation. In our method, firstly, vessels are filtered using Frangi's filter to reduce intrapulmonary noises and extract rough blood vessels. Secondly, stick tensor voting algorithm is employed to estimate the correct direction along the vessel. Then the estimated direction along the vessel is used as the anisotropic diffusion direction of vessel in VED algorithm, which makes the intensity diffusion of points locating at the vessel wall be consistent with the directions of vessels and enhance the tubular features of vessels. Finally, vessels can be extracted from the enhanced image by applying level-set segmentation method. A number of experiments results show that our method outperforms traditional VED method in vessel enhancement and results in satisfied segmented vessels.

  5. Detection of parenchymal abnormalities in experimentally induced acute pyelonephritis in rabbits using contrast-enhanced ultrasonography, CT, and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jeong Ah; Kim, Bo Hyun; Kim, Seung Kwon; Seo, Jin Won [Dept. of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Jong Sung [Laboratory Animal Research Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2016-12-15

    We evaluated the efficacy of contrast-enhanced ultrasonography (CEUS) in detecting acute pyelonephritis (APN) using the rabbit kidney model and compared it with CT and MRI. This study was approved by the Institutional Review Board. In a total of 20 New Zealand White rabbits, APN was induced experimentally. CEUS, CT, and MRI were performed on the first, third, and seventh postoperative days. After imaging studies, the subjects were sacrificed and the pathological diagnosis of APN was confirmed in each animal by a pathologist. Imaging studies were obtained in eight animals, including eight CEUS, four computed tomography (CT), and four magnetic resonance imaging (MRI) images. CEUS depicted diffuse renal enlargement (7), diffuse heterogeneous parenchymal enhancement (6), and focal areas of decreased parenchymal enhancement (6). These findings were well correlated with the CT and MRI findings in five cases in which these studies were available. CT and MRI showed diffuse renal enlargement, diffuse heterogeneous parenchymal enhancement, focal areas of decreased parenchymal enhancement, focal contour bulging, and the finding of perinephric spread of infection. In a rabbit model, CEUS could depict the parenchymal lesions of APN similar to CT or MRI; however, it was limited in depicting the perinephric extension of inflammation.

  6. PET/CT-guided biopsies of metabolically active bone lesions: applications and clinical impact

    Energy Technology Data Exchange (ETDEWEB)

    Klaeser, Bernd; Wartenberg, Jan; Weitzel, Thilo; Krause, Thomas [Bern University Hospital and University of Bern, Department of Nuclear Medicine, Inselspital, Bern (Switzerland); Wiskirchen, Jakub [Bern University Hospital and University of Bern, Department of Nuclear Medicine, Inselspital, Bern (Switzerland); University Hospital Tuebingen, Department of Radiology, Neuroradiology, and Nuclear Medicine, Tuebingen (Germany); Schmid, Ralph A. [Bern University Hospital and University of Bern, Department of Thoracic Surgery, Inselspital, Bern (Switzerland); Mueller, Michel D. [Bern University Hospital and University of Bern, Department of Obstetrics and Gynaecology, Inselspital, Bern (Switzerland)

    2010-11-15

    In a minority of cases a definite diagnosis and stage grouping in cancer patients is not possible based on the imaging information of PET/CT. We report our experience with percutaneous PET/CT-guided bone biopsies to histologically verify the aetiology of hypermetabolic bone lesions. We retrospectively reviewed the data of 20 consecutive patients who underwent multimodal image-guided bone biopsies using a dedicated PET/CT system in a step-by-step technique. Technical and clinical success rates of PET/CT-guided biopsies were evaluated. Questionnaires were sent to the referring physicians to assess the impact of biopsies on patient management and to check the clinical need for PET/CT-guided biopsies. Clinical indications for biopsy were to histologically verify the aetiology of metabolically active bone lesions without a morphological correlate confirming the suspicion of metastases in 15 patients, to determine the origin of suspected metastases in 3 patients and to evaluate the appropriateness of targeted therapy options in 2 patients. Biopsies were technically successful in all patients. In 19 of 20 patients a definite histological diagnosis was possible. No complications or adverse effects occurred. The result of PET/CT-guided bone biopsies determined a change of the planned treatment in overall 56% of patients, with intramodality changes, e.g. chemotherapy with palliative instead of curative intent, and intermodality changes, e.g. systemic therapy instead of surgery, in 22 and 50%, respectively. PET/CT-guided bone biopsies are a promising alternative to conventional techniques to make metabolically active bone lesions - especially without a distinctive morphological correlate - accessible for histological verification. PET/CT-guided biopsies had a major clinical impact in patients who otherwise cannot be reliably stage grouped at the time of treatment decisions. (orig.)

  7. [18F]Fluorodeoxyglucose (FDG)-Positron Emission Tomography (PET)/Computed Tomography (CT) in Suspected Recurrent Breast Cancer: A Prospective Comparative Study of Dual-Time-Point FDG-PET/CT, Contrast-Enhanced CT, and Bone Scintigraphy.

    Science.gov (United States)

    Hildebrandt, Malene Grubbe; Gerke, Oke; Baun, Christina; Falch, Kirsten; Hansen, Jeanette Ansholm; Farahani, Ziba Ahangarani; Petersen, Henrik; Larsen, Lisbet Brønsro; Duvnjak, Sandra; Buskevica, Inguna; Bektas, Selma; Søe, Katrine; Jylling, Anne Marie Bak; Ewertz, Marianne; Alavi, Abass; Høilund-Carlsen, Poul Flemming

    2016-06-01

    To prospectively investigate the diagnostic accuracy of [(18)F]fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) with dual-time-point imaging, contrast-enhanced CT (ceCT), and bone scintigraphy (BS) in patients with suspected breast cancer recurrence. One hundred women with suspected recurrence of breast cancer underwent 1-hour and 3-hour FDG-PET/CT, ceCT, and BS within approximately 10 days. The study was powered to estimate the precision of the individual imaging tests. Images were visually interpreted using a four-point assessment scale, and readers were blinded to other test results. The reference standard was biopsy along with treatment decisions and clinical follow-up (median, 17 months). FDG-PET/CT resulted in no false negatives and fewer false positives than the other imaging techniques. Accuracy of results were similar for 1-hour and 3-hour FDG-PET/CT. For distant recurrence, the area under the receiver operating curve was 0.99 (95% CI, 0.97 to 1) for FDG-PET/CT, 0.84 (95% CI, 0.73 to 0.94) for ceCT, and 0.86 (95% CI, 0.77 to 0.94) for the combined ceCT+BS. Of 100 patients, 22 (22%) were verified with distant recurrence, and 18 of these had bone involvement. Nineteen patients (19%) had local recurrence only. In exploratory analyses, diagnostic accuracy of FDG-PET/CT was better than ceCT alone or ceCT combined with BS in diagnosing distant, bone, and local recurrence, shown by a greater area under the receiver operating curve and higher sensitivity, specificity, and superior likelihood ratios. FDG-PET/CT was accurate in diagnosing recurrence in breast cancer patients. It allowed for distant recurrence to be correctly ruled out and resulted in only a small number of false-positive cases. Exploratory findings suggest that FDG-PET/CT has greater accuracy than conventional imaging technologies in this patient group. © 2016 by American Society of Clinical Oncology.

  8. Comparison of FDG-PET/CT and contrast-enhanced CT for monitoring therapy response in patients with metastatic breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Riedl, Christopher C.; Ulaner, Gary A.; Jochelson, Maxine S.; Weber, Wolfgang A. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Weill Cornell Medical College, Department of Radiology, New York, NY (United States); Pinker, Katja [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Ong, Leonard T. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Baltzer, Pascal [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); McArthur, Heather L. [Cedars-Sinai Medical Center, Department of Medicine, Breast Oncology, Los Angeles, CA (United States); Goenen, Mithat [Memorial Sloan Kettering Cancer Center, Department of Epidemiology and Biostatistics, New York, NY (United States); Dickler, Maura [Memorial Sloan Kettering Cancer Center, Department of Medicine, New York, NY (United States)

    2017-08-15

    The aim of this study was to compare fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and contrast-enhanced computed tomography (CE-CT) for the prediction of progression-free survival (PFS) and disease-specific survival (DSS) in patients with stage IV breast cancer undergoing systemic therapy. Sixty-five patients with metastatic breast cancer treated with first- or second-line systemic therapy in prospective clinical trials were included. Response to treatment was evaluated by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 for CE-CT and by PET Response Criteria in Solid Tumors (PERCIST), respectively. All responders by RECIST (n = 22) were also responders by PERCIST, but 40% (17/43) of non-responders by RECIST were responders by PERCIST. Responses according to RECIST and PERCIST both correlated with PFS, but PERCIST showed a significantly higher predictive accuracy (concordance index for PFS: 0.70 vs. 0.60). One-year PFS for responders vs. non-responders by RECIST was 59% vs. 27%, compared to 63% vs. 0% by PERCIST. Four-year DSS of responders and non-responders by RECIST was 50% and 38%, respectively (p = 0.2, concordance index: 0.55) as compared to 58% vs. 18% for PERCIST (p < 0.001, concordance index: 0.65). Response on PET/CT was also a significantly better predictor for DSS than disease control on CE-CT. In patients with metastatic breast cancer, tumor response on PET/CT appears to be a superior predictor of PFS and DSS than response on CE-CT. Monitoring tumor response by PET/CT may increase the power of clinical trials using tumor response as an endpoint, and may improve patient management in clinical routine. (orig.)

  9. Contrast medium enhancement of soft tissues and brain in CT examinations of dogs

    International Nuclear Information System (INIS)

    Pavlicek, M.

    2000-11-01

    CT is an x-ray based method which shows less contrast for soft tissue as has been known from radiography. Therefore, it is necessary to use intravenously administered iodine contrast media to detect and localize tumors, fistulas or other pathologic lesions. Usually contrast medium is administered manually which yields random patterns of media distribution due to varying application pressure during varying administration time, therefore enhancement of parenchymous organs could not be used to the optimum extent. The use of an automatic injection pump guarantees the necessary constancy during the examination procedure to undoubtedly detect pathologic enhancement of organs in the CT-image as known from human medicine. The standards which are expected of the injection pump and the contrast media are: a good contrast enhancement, a good accumulation in the examined organs, an accumulation, which lasts long enough during the diagnostic phase, and a rapid excretion without side effects. Because of the short scan time of the modern CT-scanner, the best contrast enhancement can be administered by a short bolus injection, which can be applied by the automatic injection pump with a defined flow and a defined quantity of contrast media. This guarantees a good enhancement in the chosen region for the duration of the scan. The main aim of this study is to find a standardized flow and quantity of contrast media for defined regions and organs considering the speed of the scanner. In a subsequent step, the existing scan-protocols are then updated using the newly found information. This study showed, that CT examination of the head and brain in middle-sized dogs can be administered with a flow of 0.5 ml/s and a dose of 2 ml of contrast medium per kg weight. The contrast enhancement of the brain is caused by the enhancement of the vessels, the parenchym is free of contrast media - brain shows a low increase of density. Only if the blood-brain-barrier is destroyed, it is possible that

  10. Contrast medium enhancement of soft tissues and brain in CT examinations of dogs

    International Nuclear Information System (INIS)

    Pavlicek, M.

    2000-11-01

    CT is a x-ray based method which shows less contrast for soft tissue as has been known from radiography. Therefore, it is necessary to use intravenously administered iodine contrast media to detect and localize tumors, fistulas or other pathologic lesions. Usually contrast medium is administered manually which yields random patterns of media distribution due to varying application pressure during varying administration time, therefore enhancement of parenchymous organs could not be used to the optimum extent. The use of an automatic injection pump guarantees the necessary constancy during the examination procedure to undoubtedly detect pathologic enhancement of organs in the CT-image as known from human medicine. The standards which are expected of the injection pump and the contrast media are: a good contrast enhancement, a good accumulation in the examined organs, an accumulation, which lasts long enough during the diagnostic phase, and a rapid excretion without side effects. Because of the short scan time of the modern CT-scanner, the best contrast enhancement can be administered by a short bolus injection, which can be applied by the automatic injection pump with a defined flow and a defined quantity of contrast media. This guarantees a good enhancement in the chosen region for the duration of the scan. The main aim of this study is to find a standardized flow and quantity of contrast media for defined regions and organs considering the speed of the scanner. In a subsequent step, the existing scan-protocols are then updated using the newly found information. This study showed, that CT examination of the head and brain in middle-sized dogs can be administered with a flow of 0.5 ml/s and a dose of 2 ml of contrast medium per kg weight. The contrast enhancement of the brain is caused by the enhancement of the vessels, the parenchym is free of contrast media - brain shows a low increase of density. Only if the blood-brain-barrier is destroyed, it is possible that

  11. The impact of 18F-FDG PET/CT in patients with liver metastases

    International Nuclear Information System (INIS)

    Chua, Siew C.; Groves, Ashley M.; Kayani, Irfan; Menezes, Leon; Gacinovic, Svetislav; Du, Yong; Bomanji, Jamshed B.; Ell, Peter J.

    2007-01-01

    The aim of this study was to assess the performance of 18 F-fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) versus dedicated contrast-enhanced CT (CECT) in the detection of metastatic liver disease. All patients that presented to our Institution with suspected metastatic liver disease who underwent 18 F-FDG PET/CT and CECT within 6 weeks of each other, were retrospectively analyzed, covering a 5-year period. One hundred and thirty-one patients (67 men, 64 women; mean age 62) were identified. Seventy-five had colorectal carcinoma and 56 had other malignancies. The performance of CECT and that of 18 F-FDG-PET/CT in detecting liver metastases were compared. The ability of each to detect local recurrence, extrahepatic metastases and to alter patient management was recorded. The final diagnosis was based on histology, clinical and radiological follow-up (mean 23 months). In detecting hepatic metastases, 18 F-FDG-PET/CT yielded 96% sensitivity and 75% specificity, whilst CECT showed 88% sensitivity and 25% specificity. 18 F-FDG-PET/CT and CECT were concordant in 102 out of 131 patients (78%). In the colorectal group 18 F-FDG-PET/CT showed 94% sensitivity and 75% specificity, whilst CECT had 91% sensitivity and 25% specificity. In the noncolorectal group 18 F-FDG-PET/CT showed 98% sensitivity and 75% specificity whilst CECT had 85% sensitivity and 25% specificity. Overall, 18 F-FDG-PET/CT altered patient management over CECT in 25% of patients. CECT did not alter patient management over 18 F-FDG-PET/CT alone in any patients. 18 F-FDG-PET/CT performed better in detecting metastatic liver disease than CECT in both colorectal and noncolorectal malignancies, and frequently altered patient management. The future role of CECT in these patients may need to be re-evaluated to avoid potentially unnecessary duplication of investigation where 18 F-PET/CT is readily available. (orig.)

  12. Role of contrast-enhanced helical CT in the evaluation of acute thoracic aortic injuries after blunt chest trauma

    International Nuclear Information System (INIS)

    Scaglione, M.; Pinto, A.; Pinto, F.; Romano, L.; Ragozzino, A.; Grassi, R.

    2001-01-01

    The purpose of this retrospective study was to determine the value of contrast-enhanced helical CT for detecting and managing acute thoracic aortic injury (ATAI). Between June 1995 and February 2000, 1419 consecutive chest CT examinations were performed in the setting of major blunt trauma. The following CT findings were considered indicative of ATAI: intimal flap; pseudoaneurysm; contour irregularity; lumen abnormality; and extravasation of contrast material. On the basis of these direct findings no further diagnostic investigations were performed. Isolated mediastinal hematoma on CT scans was considered an indirect sign of ATAI: In these cases, thoracic aortography was performed even if CT indicated normal aorta. Seventy-seven patients had abnormal CT scans: Among the 23 patients with direct CT signs, acute thoracic aortic injuries was confirmed at thoracotomy in 21. Two false-positive cases were observed. The 54 remaining patients had isolated mediastinal hematoma without aortic injuries at CT and corresponding negative angiograms. The 1342 patients with negative CT scans were included in the 8-month follow-up program and did not show any adverse sequela based on clinical and radiographic criteria. Contrast-enhanced helical CT has a critical role in the exclusion of thoracic aortic injuries in patient with major blunt chest trauma and prevents unnecessary thoracic aortography. Direct CT signs of ATAI do not require further diagnostic investigations to confirm the diagnosis: Isolated aortic bands or contour vessel abnormalities should be first considered as possible artifacts or related to non-traumatic etiologies especially when mediastinal hematoma is absent. In cases of isolated mediastinal hematoma other possible sources of bleeding should be considered before directing patients to thoracic aortography. (orig.)

  13. Detection of underlying malignancy in patients with paraneoplastic neurological syndromes: comparison of {sup 18}F-FDG PET/CT and contrast-enhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    Schramm, N.; Schmid-Tannwald, C.; Meinel, F.G.; Reiser, M.F.; Rist, C. [Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Munich (Germany); Rominger, A. [Ludwig-Maximilians-University Hospital Munich, Department of Nuclear Medicine, Munich (Germany); Schmidt, C. [Ludwig-Maximilians-University Hospital Munich, Department of Neurology, Munich (Germany); Morelli, J.N. [Texas A and M Health Sciences Center, Department of Radiology, Temple, TX (United States)

    2013-07-15

    To determine the value of combined {sup 18}F-FDG PET/CT with diagnostic contrast-enhanced CT (CECT) in detecting primary malignancies and metastases in patients with paraneoplastic neurological syndromes (PNS) and to compare this with CECT alone. PET/CT scans from 66 patients with PNS were retrospectively evaluated. Two blinded readers initially reviewed the CECT portion of each PET/CT scan. In a second session 3 months later, the readers analysed the combined PET/CT scans. Findings on each study were assessed using a four-point-scale (1 normal/benign; 2 inconclusive, further diagnostic work-up may be necessary; 3 malignant; 4 inflammatory). Sensitivity and specificity for malignant findings were calculated for PET/CT and CECT. Interreader agreement was determined by calculating Cohen's kappa. Pooled data from clinical follow-up (including histopathology and follow-up imaging, median follow-up 20.0 months) served as the reference gold standard. Both readers classified 12 findings in ten patients (15 %) as malignant on the PET/CT scans (two patients had two primary tumours). One such imaging finding (suspected thymic cancer) was false-positive (i.e. benign histology). The most common tumours were bronchial carcinoma (n = 3), lymph node metastases of gynaecological tumours (n = 3) and tonsillar carcinoma (n = 2). Three of 12 findings (25 %) were not detected by CECT alone (cervical carcinoma, lymph node metastasis and tonsillar carcinoma). In a per-patient analysis, sensitivity and specificity for malignant findings were 100 % and 90 % for PET/CT and 78 % and 88 % for CECT. In 24 % (reader 1) and 21 % (reader 2) of the patients, the PET/CT findings were inconclusive. Of these findings, 57 % (reader 1) and 56 % (reader 2) were only diagnosed with PET (e.g. focal FDG uptake of the thyroid, gastrointestinal tract and ovaries). On follow-up, none of these findings corresponded to malignancy. Overall agreement between the two readers was excellent with a Cohen

  14. How to reduce nephropathy following contrast-enhanced CT: A lesson in policy implementation

    International Nuclear Information System (INIS)

    Richenberg, J.

    2012-01-01

    In excess of 50 contrast-enhanced computed tomography (CT) examinations are typically undertaken in our tertiary hospital NHS Trust each weekday, approximately 13,000 each year. In the Department of Radiology alone, we inject more than 1300 l of iodinated contrast medium per annum. There is a real need to devise a policy to anticipate contrast medium-induced nephropathy (CIN) and minimize its effects, without disrupting the high-intensity CT service. Having written a comprehensive yet pragmatic policy to reduce the incidence of this iatrogenic condition, it seemed sensible to share it with the wider radiology community and share the experience and lessons learnt in engaging all the stakeholders, ushering in the change with as little fuss as possible. The ramifications on primary and secondary care had to be anticipated, resource implications managed, and staff trained. This review is therefore presented in four sections: framing the problem, assessing its size and nature; a succeeding section on the available guidelines and their uptake; the policy itself to reduce CIN in CT is presented in the third section; and crucially, a description of the policy introduction process in the last section.

  15. Evaluation of adverse events and imaging quality in contrast-enhanced abdominal CT using generic CT contrast developed in South Korea: A multicenter prospective observational study

    International Nuclear Information System (INIS)

    Kim, You Sung; Jung, Seung Eun; Park, Micheal Yong; Rha, Sung Eun; Lee, Soo Rim; Hwang, Seong Su; Lim, Yeon Soo; Park, Jeong Mi

    2017-01-01

    The purpose of this study is to evaluate the clinical safety and usefulness of the Prosure®300 in contrast-enhanced abdominal CT. This prospective study was approved by our center's Institutional Review Board. This study included 727 patients in four hospitals who underwent contrast-enhanced abdominal CT using Prosure®300 from December 2010 to June 2011. Adverse events were classified into minor and major adverse events. Logistic regression analysis was used to evaluate the relationship between adverse events and patient gender, age, underlying disease, and amount of injected contrast agent. Two radiologists independently evaluated imaging quality as poor, insufficient, sufficient, good, or very good. One hundred seventy-six out of 727 patients complained of adverse events, but most of them were minor adverse events. Five patients complained of dyspnea and one patient had hoarseness, but recovered without treatment. The rate of adverse events was significantly higher in men (p = 0.011), and a greater amount of injected contrast agent was related to a higher rate of adverse events (p = 0.000). Imaging quality was evaluated as 'good' or 'very good' in all cases. Prosure®300, a generic CT contrast agent developed in South Korea, can be used in contrast-enhanced abdominal CT

  16. Evaluation of adverse events and imaging quality in contrast-enhanced abdominal CT using generic CT contrast developed in South Korea: A multicenter prospective observational study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, You Sung [Dept. of Radiology, Ilsan Paik Hospital, College of Medicine, Inje University, Goyang (Korea, Republic of); Jung, Seung Eun; Park, Micheal Yong; Rha, Sung Eun [Dept. of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of); Lee, Soo Rim [Dept. of Radiology, Uijeongbu St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu (Korea, Republic of); Hwang, Seong Su [Dept. of Radiology, St. Vincent Hospital, College of Medicine, The Catholic University of Korea, Suwon (Korea, Republic of); Lim, Yeon Soo [Dept. of Radiology, Bucheon St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Bucheon (Korea, Republic of); Park, Jeong Mi [Dept. of Radiology, Yeouido St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2017-02-15

    The purpose of this study is to evaluate the clinical safety and usefulness of the Prosure®300 in contrast-enhanced abdominal CT. This prospective study was approved by our center's Institutional Review Board. This study included 727 patients in four hospitals who underwent contrast-enhanced abdominal CT using Prosure®300 from December 2010 to June 2011. Adverse events were classified into minor and major adverse events. Logistic regression analysis was used to evaluate the relationship between adverse events and patient gender, age, underlying disease, and amount of injected contrast agent. Two radiologists independently evaluated imaging quality as poor, insufficient, sufficient, good, or very good. One hundred seventy-six out of 727 patients complained of adverse events, but most of them were minor adverse events. Five patients complained of dyspnea and one patient had hoarseness, but recovered without treatment. The rate of adverse events was significantly higher in men (p = 0.011), and a greater amount of injected contrast agent was related to a higher rate of adverse events (p = 0.000). Imaging quality was evaluated as 'good' or 'very good' in all cases. Prosure®300, a generic CT contrast agent developed in South Korea, can be used in contrast-enhanced abdominal CT.

  17. The impact of respiratory motion on tumor quantification and delineation in static PET/CT imaging

    International Nuclear Information System (INIS)

    Liu Chi; Pierce II, Larry A; Alessio, Adam M; Kinahan, Paul E

    2009-01-01

    Our aim is to investigate the impact of respiratory motion on tumor quantification and delineation in static PET/CT imaging using a population of patient respiratory traces. A total of 1295 respiratory traces acquired during whole body PET/CT imaging were classified into three types according to the qualitative shape of their signal histograms. Each trace was scaled to three diaphragm motion amplitudes (6 mm, 11 mm and 16 mm) to drive a whole body PET/CT computer simulation that was validated with a physical phantom experiment. Three lung lesions and one liver lesion were simulated with diameters of 1 cm and 2 cm. PET data were reconstructed using the OS-EM algorithm with attenuation correction using CT images at the end-expiration phase and respiratory-averaged CT. The errors of the lesion maximum standardized uptake values (SUV max ) and lesion volumes between motion-free and motion-blurred PET/CT images were measured and analyzed. For respiration with 11 mm diaphragm motion and larger quiescent period fraction, respiratory motion can cause a mean lesion SUV max underestimation of 28% and a mean lesion volume overestimation of 130% in PET/CT images with 1 cm lesions. The errors of lesion SUV max and volume are larger for patient traces with larger motion amplitudes. Smaller lesions are more sensitive to respiratory motion than larger lesions for the same motion amplitude. Patient respiratory traces with relatively larger quiescent period fraction yield results less subject to respiratory motion than traces with long-term amplitude variability. Mismatched attenuation correction due to respiratory motion can cause SUV max overestimation for lesions in the lower lung region close to the liver dome. Using respiratory-averaged CT for attenuation correction yields smaller mismatch errors than those using end-expiration CT. Respiratory motion can have a significant impact on static oncological PET/CT imaging where SUV and/or volume measurements are important. The impact

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

    Science.gov (United States)

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

    2011-01-01

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

  19. Quantitative contrast-enhanced CT attenuation evaluation of osseous metastases following chemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Connie Y.; Simeone, F.J.; Torriani, Martin; Bredella, Miriam A. [Massachusetts General Hospital, Division of Musculoskeletal Imaging and Intervention, Department of Radiology, Boston, MA (United States)

    2017-10-15

    Osseous metastases often undergo an osteoblastic healing response following chemotherapy. The purpose of our study was to demonstrate the quantitative CT changes in attenuation of osseous metastases before and after chemotherapy. Our study was IRB approved and HIPAA compliant. Our cohort consisted of 86 consecutive cancer patients with contrast-enhanced CTs before and 14 ± 2 (12-25) months after initiation of chemotherapy (60 ± 11 years, 36 males, 50 females). The average and maximum metastasis attenuations were measured in Hounsfield units (HU) by two readers. Treatment effects were assessed using paired t-tests and Fisher exact tests. Intraclass correlation coefficients (ICCs) were calculated. Patient records were reviewed to determine the patient's clinical status (worse, unchanged, or improved) at the time of follow-up CT. The distribution of lesion types was as follows: lytic (30/86, 35%), blastic (43/86, 50%), and mixed lytic-blastic (13/86, 15%). There was a significant increase in average and maximum CT attenuation of metastases following chemotherapy for all patients, which remained statistically significant when stratified by lesion type, clinical status (worsening or improving/stable), cancer type (breast, lung), and radiation therapy (P < 0.05). In a subgroup of patients whose osseous metastases decreased in average attenuation (14/86, 16%), more patients had a worse clinical status (11/14, 79%) (P = 0.02). ICC was almost perfect for average attenuation and substantial for maximum attenuation. Quantitative assessment of osseous metastatic disease using CT attenuation measurements demonstrated a statistically significant increase in attenuation more than 12 months after initiation of chemotherapy. (orig.)

  20. SU-F-J-71: Improving CT Quality for Radiation Therapy Planning and Delivery Guidance Using a Non-Linear Contrast Enhancement Technique

    Energy Technology Data Exchange (ETDEWEB)

    Noid, G; Tai, A; Li, X [Medical College of Wisconsin, Milwaukee, WI (United States)

    2016-06-15

    Purpose: Advanced image post-processing techniques which enhance soft-tissue contrast in CT have not been widely employed for RT planning or delivery guidance. The purpose of this work is to assess the soft-tissue contrast enhancement from non-linear contrast enhancing filters and its impact in RT. The contrast enhancement reduces patient alignment uncertainties. Methods: Non-linear contrast enhancing methods, such as Best Contrast (Siemens), amplify small differences in X-ray attenuation between two adjacent structure without significantly increasing noise. Best Contrast (BC) separates a CT into two frequency bands. The low frequency band is modified by a non-linear scaling function before recombination with the high frequency band. CT data collected using a CT-on-rails (Definition AS Open, Siemens) during daily CT-guided RT for 6 prostate cancer patients and an image quality phantom (The Phantom Laboratory) were analyzed. Images acquired with a standard protocol (120 kVp, 0.6 pitch, 18 mGy CTDIvol) were processed before comparison to the unaltered images. Contrast and noise were measured in the the phantom. Inter-observer variation was assessed by placing prostate contours on the 12 CT study sets, 6 enhanced and 6 unaltered, in a blinded study involving 8 observers. Results: The phantom data demonstrate that BC increased the contrast between the 1.0% supra-slice element and the background substrate by 46.5 HU while noise increased by only 2.3 HU. Thus the contrast to noise ratio increased from 1.28 to 6.71. Furthermore, the variation in centroid position of the prostate contours was decreased from 1.3±0.4 mm to 0.8±0.3 mm. Thus the CTV-to-PTV margin was reduced by 1.1 mm. The uncertainty in delineation of the prostate/rectum edge decreased by 0.5 mm. Conclusion: As demonstrated in phantom and patient scans the BC filter accentuates soft-tissue contrast. This enhancement leads to reduced inter-observer variation, which should improve RT planning and delivery

  1. Brain tumors and CT scan in infants and children, (1). The impact on pediatric neuroradiology

    Energy Technology Data Exchange (ETDEWEB)

    Ohi, S; Velasco, J M [Northwestern Univ., Chicago, IL (USA). Medical School

    1980-10-01

    The dramatic change in the neuroradiological procedures have been noted after CT scan was introduced in the last several years. Remarkable decreasing numbers of angiographic, pneumoencephalographic and other invasive neuroradiologic studies as well as nuclear brain scan were also found in the pediatric neuroradiology. The authors analyzed the total numbers of these studies performed in the last several years in pediatric neurological/neurosurgical practice in the light of the impact of CT scan especially in the diagnostic procedures and treatments of brain tumor in children. Although the number of these procedures decreased up to 49% in plain skull X-ray, 54% in cerebral angiography, 70% in pneumoencephalography/ventriculography and 79% in nuclear brain scan after CT scan was installed in our results, it is extremely important to renew understanding of those characteristics in each special procedures. Cerebral angiography as well as pneumoencephalography may give the surgeon more precise ideas of the anatomical relationship between the lesion and other normal structures, especially in the posterior fossa tumor in which CT scan occassionally demonstrates only a gross finding. A case with false negative result and another case with a complicated anatomical structure in CT scan were presented. The significance of cerebral angiography and other invasive studies in the diagnosis and follow up of brain tumor in CT scan were discussed.

  2. Preoperative detection of hepatocellular carcinoma: comparison of combined constrast-enhanced MR imaging and combined CT during arterial portography and CT hepatic arteriography

    International Nuclear Information System (INIS)

    Kwak, H.S.; Kim, C.S.; Lee, J.M.; Seoul National University Medical Research Center

    2004-01-01

    The aim of this study was to compare Gd-DTPA-enhanced dynamic MR images, superparamagnetic iron oxide (SPIO)-enhanced MR images, combined Gd-DTPA-enhanced dynamic and SPIO-enhanced MR images, vs combined CT arterial portography (CTAP) and CT hepatic arteriography (CTHA), in the detection of hepatocellular carcinoma (HCC) using receiver operating characteristic (ROC) analysis. Twenty-four patients with 38 nodular HCCs (5-60 mm, mean 23.0 mm) were retrospectively analyzed. Image reviews were conducted on a liver segment-by-segment basis. A total of 192 segments, including 36 segments with 38 HCC, were reviewed independently by three radiologists. Each radiologist read four sets of images (set 1, unenhanced and Gd-DTPA-enhanced dynamic MR images; set 2, unenhanced and SPIO-enhanced MR images; set 3, combined Gd-DTPA-enhanced dynamic and SPIO-enhanced MR images; set 4, combined CTAP and CTHA). To minimize any possible learning bias, the reviewing order was randomized and the reviewing procedure was performed in four sessions at 2-week intervals. The diagnostic accuracy (Az values) for HCCs of combined CTAP and CTHA, combined Gd-DTPA-enhanced dynamic and SPIO-enhanced MR images, Gd-DTPA-enhanced dynamic MR images, and SPIO-enhanced MR images for all observers were 0.934, 0.963, 0.878, and 0.869, respectively. The diagnostic accuracy of combined CTAP and CTHA and combined Gd-DTPA-enhanced dynamic and SPIO-enhanced MR images was significantly higher than Gd-DTPA-enhanced dynamic MR images or SPIO-enhanced MR images (p<0.005). The mean specificity of combined CTAP and CTHA (93%) and combined Gd-DTPA-enhanced dynamic and SPIO-enhanced MR images (95%) was significantly higher than Gd-DTPA-enhanced dynamic MR images (87%) or SPIO-enhanced MR images (88%; p<0.05). Combined Gd-DTPA-enhanced dynamic and SPIO-enhanced MR images may obviate the need for more invasive combined CTAP and CTHA for the preoperative evaluation of patients with HCC

  3. Volumetric dynamic contrast enhanced Computed Tomography (DCE-CT) for preoperative assessment of the vascularity of spinal metastases

    DEFF Research Database (Denmark)

    Lauridsen, Carsten Ammitzbøl

    Purpose To investigate the feasibility of measuring and grading the vascularity of spinal metastases using dynamic contrast enhanced CT (DCE-CT). Materials and methods Prior to surgical treatment of symptomatic metastatic spinal cord compression, 20 patients were examined using DCE-CT. The 320......–detector row CT scanner allowed a volumetric acquisition over a range of 16 cm, covering three to four vertebrae. Image analysis was performed at a dedicated workstation, encompassing quantitative and qualitative measurement of the arterial flow (AF) in mL/min/100mL of the vertebrae. The perfusion values...... were analysed using a single input, maximum slope model. The AF assessed by DCE-CT of affected and non-affected vertebrae will be compared, and furthermore, the correlation between AF and intraoperative blood loss will be examined. Results Preliminary results for 5 patients: In two patients the AF...

  4. Relationships of site of impact to CT findings and outcome in diffuse brain injury

    International Nuclear Information System (INIS)

    Saito, Akihito; Kuwana, Nobumasa; Mochimatsu, Yasuhiko; Tanaka, Naoki; Fujino, Hideyo

    1985-01-01

    The relationships of the site of impact to the CT findings and to the severity and outcome of an injury were analysed based on 50 cases of diffuse brain injury (DBI). The CT findings of DBI were classified into 5 types: diffuse cerebral swelling (DCS); isodensity hemispheric swelling (IHS); deep-seated brain injury (DSI); subarachnoid hemorrhage (SAH), and normal finding (N). The sites of the impact were frontal in 19 cases, temporal in 8 cases, parietal in 4 cases, occipital in 12 cases, and multiple or undetermined in 7 cases. Frontal blows resulted in the lowest mortality rate (5.3%); on the other hand, occipital blows resulted in the highest (58%). Additionally, occipital blows caused the highest primary brain-stem injury, i.e., 41.7%. The frontal region was the most common impact area, revealing DCS and N. Temporal blows commonly resulted in DSI. Parietal blows were characteristic causes of IHS cases. However, occipital blows generally demonstrated no specific tendencies with regard to the type of CT finding. Based on this study, it is evident that CT findings and outcomes are influenced by the location of the impact. It is the authors' impression that, in severe head-injury cases, occipital blows, which are usually associated with primary brain-stem injuries, are the most serious. (author)

  5. Relationships of site of impact to CT findings and outcome in diffuse brain injury

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Akihito; Kuwana, Nobumasa; Mochimatsu, Yasuhiko; Tanaka, Naoki; Fujino, Hideyo

    1985-02-01

    The relationships of the site of impact to the CT findings and to the severity and outcome of an injury were analysed based on 50 cases of diffuse brain injury (DBI). The CT findings of DBI were classified into 5 types: diffuse cerebral swelling (DCS); isodensity hemispheric swelling (IHS); deep-seated brain injury (DSI); subarachnoid hemorrhage (SAH), and normal finding (N). The sites of the impact were frontal in 19 cases, temporal in 8 cases, parietal in 4 cases, occipital in 12 cases, and multiple or undetermined in 7 cases. Frontal blows resulted in the lowest mortality rate (5.3%); on the other hand, occipital blows resulted in the highest (58%). Additionally, occipital blows caused the highest primary brain-stem injury, i.e., 41.7%. The frontal region was the most common impact area, revealing DCS and N. Temporal blows commonly resulted in DSI. Parietal blows were characteristic causes of IHS cases. However, occipital blows generally demonstrated no specific tendencies with regard to the type of CT finding. Based on this study, it is evident that CT findings and outcomes are influenced by the location of the impact. It is the authors' impression that, in severe head-injury cases, occipital blows, which are usually associated with primary brain-stem injuries, are the most serious. (author).

  6. Krypton-enhanced ventilation CT with dual energy technique: experimental study for optimal krypton concentration.

    Science.gov (United States)

    Chung, Yong Eun; Hong, Sae Rom; Lee, Mi-Jung; Lee, Myungsu; Lee, Hye-Jeong

    2014-11-01

    To assess the feasibility of krypton-enhanced ventilation CT using dual energy (DE) technique for various krypton concentrations and to determine the appropriate krypton concentration for DE ventilation CT through an animal study. Baseline DECT was first performed on seven New Zealand white rabbits. The animals were then ventilated using 20%, 30%, 40%, 50%, 60%, to 70% krypton concentration, and DECT was performed for each concentration. Krypton extraction was performed through a workstation, and results were displayed on a color map. Overlay Hounsfield unit (HU) values were obtained by two observers in consensus readings. A linear mixed model was used to correlate overlay HU values and krypton concentrations. Visual assessments of the homogeneity of krypton maps were also performed. Mean overlay HU values according to krypton concentration were as follows; 20% krypton, 1.68 ± 5.15; 30% krypton, 3.73 ± 5.93; 40% krypton, 6.92 ± 5.51; 50% krypton, 10.88 ± 5.17; 60% krypton, 14.54 ± 4.23; and 70% krypton, 18.79 ± 3.63. We observed a significant correlation between overlay HU values on krypton maps and krypton concentrations (P krypton color maps, all observers determined universal enhancement on the 70% krypton map for all animals. It is feasible to evaluate lung ventilation function using DECT with a krypton concentration of at least 70%.

  7. Preliminary study of single contrast enhanced dual energy heart imaging using dual-source CT

    International Nuclear Information System (INIS)

    Peng Jin; Zhang Longjiang; Zhou Changsheng; Lu Guangming; Ma Yan; Gu Haifeng

    2009-01-01

    Objective: To evaluate the feasibility and preliminary applications of single contrast enhanced dual energy heart imaging using dual-source CT (DSCT). Methods: Thirty patients underwent dual energy heart imaging with DSCT, of which 6 cases underwent SPECT or DSA within one week. Two experienced radiologists assessed image quality of coronary arteries and iodine map of myocardium. and correlated the coronary artery stenosis with the perfusion distribution of iodine map. Results: l00% (300/300) segments reached diagnostic standards. The mean score of image for all patients was 4.68±0.57. Mural coronary artery was present in 10 segments in S cases, atherosclerotic plaques in 32 segments in 12 cases, of which 20 segments having ≥50% stenosis, 12 segments ≤50% stenosis; dual energy CT coronary angiography was consistent with the DSA in 3 patients. 37 segmental perfusion abnormalities on iodine map were found in 15 cases, including 28 coronary blood supply segment narrow segment and 9 no coronary stenosis (including three negative segments in SPECD. Conclusion: Single contrast enhanced dual energy heart imaging can provide good coronary artery and myocardium perfusion images in the patients with appropriate heart rate, which has a potential to be used in the clinic and further studies are needed. (authors)

  8. Clinical value of FDG PET/CT in the diagnosis of suspected recurrent ovarian cancer: is there an impact of FDG PET/CT on patient management?

    International Nuclear Information System (INIS)

    Bilici, Ahmet; Ustaalioglu, Bala Basak Oven; Seker, Mesut; Salepci, Taflan; Gumus, Mahmut; Canpolat, Nesrin; Tekinsoy, Bulent

    2010-01-01

    The aim of this study was to evaluate the clinical value of FDG PET/CT in patients with suspected ovarian cancer recurrence as compared with diagnostic CT, and to assess the impact of the results of FDG PET/CT on treatment planning. Included in this retrospective study were 60 patients with suspected recurrent ovarian cancer who had previously undergone primary debulking surgery and had been treated with adjuvant chemotherapy. Diagnostic CT and FDG PET/CT imaging were performed for all patients as clinically indicated. The changes in the clinical management of patients according to the results of FDG PET/CT were also analysed. FDG PET/CT was performed in 21 patients with a previously negative or indeterminate diagnostic CT scan, but an elevated CA-125 level, and provided a sensitivity of 95% in the detection of recurrent disease. FDG PET/CT revealed recurrent disease in 19 patients. In 17 of 60 patients, the indication for FDG PET/CT was an elevated CA-125 level and an abnormal diagnostic CT scan to localize accurately the extent of disease. FDG PET/CT scans correctly identified recurrent disease in 16 of the 17 patients, a sensitivity of 94.1%. Moreover, FDG PET/CT was performed in 18 patients with clinical symptoms of ovarian cancer recurrence, an abnormal diagnostic CT scan, but a normal CA-125 level. In this setting, FDG PET/CT correctly confirmed recurrent disease in seven patients providing a sensitivity of 100% in determining recurrence. In four patients, FDG PET/CT was carried out for the assessment of treatment response. Three of four scans were classified as true-negative indicating a complete response. In the other patient, FDG PET/CT identified progression of disease. In total, 45 (75%) of the 60 patients had recurrent disease, in 14 (31.1%) documented by histopathology and in 31 (68.9%) on clinical follow-up, while 15 (25%) had no evidence of recurrent disease. The overall sensitivity, specificity, accuracy, and positive and negative predictive value

  9. 18F-Fluorodeoxyglucose PET/CT and dynamic contrast-enhanced MRI as imaging biomarkers in malignant pleural mesothelioma

    OpenAIRE

    Hall, D. O.; Hooper, C. E.; Searle, J.; Darby, M.; White, P.; Harvey, J. E.; Braybrooke, J. P.; Maskell, N. A.; Masani, V.; Lyburn, I. D.

    2018-01-01

    Purpose\\ud \\ud The purpose of this study was to compare the use of fluorine-18-fluorodeoxyglucose (18F-FDG) PET with computed tomography (CT) and dynamic contrast-enhanced (DCE) MRI to predict prognosis and monitor treatment in malignant pleural mesothelioma.\\ud \\ud Patients and methods\\ud \\ud 18F-FDG PET/CT and DCE-MRI studies carried out as part of the South West Area Mesothelioma Pemetrexed trial were used. 18F-FDG PET/CT and DCE-MRI studies were carried out before treatment, and after two...

  10. 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

  11. The impact of PET/CT on the management of hepatic and extra hepatic metastases from gastrointestinal cancers

    Energy Technology Data Exchange (ETDEWEB)

    Polat, Erdal, E-mail: erdal066@yahoo.com [Kartal Kosuyolu High Specialty Training and Research Hospital, Department of Gastrointestinal Surgery, Istanbul (Turkey); Bostanci, Erdal Birol [Sakarya University, Faculty of Medicine, Department of General Surgery, Sakarya (Turkey); Aksoy, Erol [Turkiye Yuksek Ihtisas Teaching and Research Hospital, Department of Gastroenterological Surgery, Ankara (Turkey); Karaman, Kerem [Sakarya University, Faculty of Medicine, Department of General Surgery, Sakarya (Turkey); Poyraz, Nilufer Yildirim [Ataturk Teaching and Research Hospital, Department of Nuclear Medicine, Ankara (Turkey); Duman, Ugur [Sevket Yilmaz Training and Research Hospital, Department of General Surgery, Bursa (Turkey); Gencturk, Zeynep Biyikli [Ankara University, Faculty of Medicine, Department of Biostatistics, Ankara (Turkey); Yol, Sinan [Medeniyet University, Faculty of Medicine, Department of General surgery, Istanbul (Turkey)

    2015-06-15

    Highlights: • CT is more sensitive than PET/CT in detecting hepatic metastases. • PET/CT is more specific in detecting hepatic metastases. • CT and PET/CT have equal sensitivity in detecting extra hepatic metastases. • PET/CT is more specific in detecting extra hepatic metastases. • PET/CT has an impact of about 40% on changing the management strategies. - Abstract: Purpose: To investigate the efficacy of positron emission tomography/computed tomography (PET/CT) in detection and management of hepatic and extrahepatic metastases from gastrointestinal cancers. Materials and methods: Between February 2008 and July 2010, patients histopathologically diagnosed with gastrointestinal cancer and showing suspected metastasis on CT screening were subsequently evaluated with PET/CT. All patients were subgrouped according to histopathological origin and localization of the primary tumor. Localization of gastrointestinal cancers was further specified as lower gastrointestinal system (GIS), upper GIS, or hepato-pancreato-biliary (HPB). Both accuracy and impact of CT and PET/CT on patient management were retrospectively evaluated. Results: One hundred and thirteen patients diagnosed histopathologically with gastrointestinal cancers were retrospectively evaluated. Seventy-nine patients had adenocarcinoma and 34 patients other gastrointestinal tumors. Forty-one patients were in the upper GIS group, 30 patients in the HPB group, and 42 patients in the lower GIS group. Evaluation the diagnostic performance of PET/CT for suspected metastasis according to histopathological origin of the tumor, revealed that the sensitivity of PET/CT – although statistically not different – was higher in adenocarcinomas than in non-adenocarcinomas (90% (95% CI, 0.78–0.96) vs. 71.4% (95% CI, 0.45–0.88), P = 0.86). The specificity was not significantly different (85.7% (95% CI, 0.70–0.93) vs. 85% (95% CI, 0.63–0.94), P = 1.00). In the overall patient group; CT was significantly more

  12. Multislice CT of the liver. Effects of contrast material pushed with saline solution on hepatic enhancement

    International Nuclear Information System (INIS)

    Sekiguchi, Ryuzo; Hayashi, Takayuki; Tsukamoto, Tatsuaki; Kuroki, Yoshinori; Nasu, Katsuhiro; Murakami, Koji; Nawano, Shigeru

    2004-01-01

    The purpose of this study was to evaluate the usefulness of a method of power injection of contrast material pushed with saline solution for hepatic multislice CT using a dual-head power injector. One hundred twenty-one patients who underwent multislice CT to detect liver metastases were divided into two groups, depending on the protocol of contrast material administration: 100 mL of non-ionic contrast material (370 mgI/mL) or 100 mL of the same contrast material pushed with 30 mL of saline solution. Both contrast material and saline solution were administered at a rate of 2.5 mL/sec using a dual-head power injector. Attenuation values for the two protocols were obtained from the liver, portal vein, and descending aorta. Hepatic enhancement above 50 Hounsfield unit (HU), which is needed for the diagnosis of liver metastases, was achieved in 76.5% of patients given 100 mL of contrast material and 92.5% of those given 100 mL of contrast material pushed with a 30 mL saline solution. In contingency-table analysis, the CT attenuation value of liver categorized as less than 50 HU or more than 50 HU, showed a good relation between the categorized group and the protocol (p=0.0437). In patients with a body weight of 50 kg or more, 100 mL of contrast material pushed with saline solution provided significantly better CT attenuation values in the liver (p=0.0113), portal vein (p=0.0094), and descending aorta (p=0.0394) than those provided by the injection of 100 mL of contrast material alone. When contrast material pushed with saline solution was used, CT attenuation values in the liver were significantly increased, especially in patients with a body weight of 50 kg or more. This technique will provide a decrease in the volume of contrast material administered and a potential decrease in the side effects of contrast material. (author)

  13. The value of contrast-enhanced 64-row CT in differentiating benign from malignant serous ovarian neoplasms

    International Nuclear Information System (INIS)

    Dong Tianfa; Wu Meixian; Zhang Jiayun; Song Ting

    2009-01-01

    Objective: To assess the diagnostic value of contrast-enhanced 64-row CT scanning in deciding benign or malignant serous ovarian tumors. Methods: Fifty-eight cases of serous ovarian tumors proved pathologically were reviewed, including 25 malignant tumors, 25 benign, 8 borderline tumors. All patients underwent 64-row CT scanning, including plain scanning and contrast-enhance scanning. The tumors' shape, density, blood supply and enhancement features were evaluated. Results: Twenty-five cases of benign serous cystic adenoma were mostly unicameral, and showed a moderate mural enhancement only in 4 cases (16%) due to chronic pelvic infection and the others (21/25, 84%) had no of slight enhancement. Malignant tumors were cystic-solid mass with unclear margin, irregular shape and septa. Twenty-two cases of serous cystadenocarcinoma out of 25 cases (88%) appeared obvious enhancement and other 3 cases no enhancement. And 7 cases out of 8 (87.5%) borderlined serous cystadenomas showed different enhancement patterns. Conclusion: Benign ovarian serous neoplasms were mostly unicameral and no strong mural enhancement, suggesting a lack of blood supply. While, there were obvious enhancement in the ovarian serous cystadenocarcinoma and borderline serous cystadenoma with malignant potential. The 64-row CT is helpful for differentiating the nature of the serous ovarian neoplasm. (authors)

  14. Therapeutic impact of CT-guided percutaneous catheter drainage in treatment of deep tissue abscesses

    International Nuclear Information System (INIS)

    Asai, Nobuhiro; Ohkuni, Yoshihiro; Kaneko, Norihiro; Aoshima, Masahiro; Yamazaki, Ikuo; Kawamura, Yasutaka

    2013-01-01

    Combination therapy of CT-guided percutaneous drainage and antibiotics is the first-line treatment for abscesses. Its effectiveness has been demonstrated. However, the therapeutic impact of this procedure for infection treatment has never been reported. We retrospectively analyzed all 47 patients who received CT-guided percutaneous drainage for infection treatment. Patients' characteristics, pathogens isolated, antibiotics administered, technical and clinical outcomes, complications related to this procedure and therapeutic impacts were investigated. Patients were 26 males and 21 females. The mean age was 63.5 years (±18.7). The diseases targeted were 19 retroperitoneal abscesses, 18 intraabdominal abscesses, three pelvic abscesses, and seven others. As for technical outcomes, all of the 54 procedures (100%) were successful. As for clinical outcomes, 44 (93.6%) were cured and three patients (6.4%) died. No complications related to this procedure were found in this study. A total of 42 patients (88%) had a change in the management of their infection as a result of CT-guided percutaneous drainage, such as selection and discontinuation of antibiotics. In conclusion, CT-guided percutaneous drainage is a safe and favorable procedure in the treatment of deep tissue abscesses. Therapeutic impact of these procedures helped physicians make a rational decision for antibiotics selection. (author)

  15. Quantifying the impact of µCT-scanning of human fossil teeth on ESR age results.

    Science.gov (United States)

    Duval, Mathieu; Martín-Francés, Laura

    2017-05-01

    Fossil human teeth are nowadays systematically CT-scanned by palaeoanthropologists prior to any further analysis. It has been recently demonstrated that this noninvasive technique has, in most cases, virtually no influence on ancient DNA preservation. However, it may have nevertheless an impact on other techniques, like Electron Spin Resonance (ESR) dating, by artificially ageing the apparent age of the sample. To evaluate this impact, we µCT-scanned several modern enamel fragments following the standard analytical procedures employed by the Dental Anthropology Group at CENIEH, Spain, and then performed ESR dose reconstruction for each of them. The results of our experiment demonstrate that the systematic high-resolution µCT-scanning of fossil hominin remains introduces a nonnegligible X-ray dose into the tooth enamel, equivalent to 15-30 Gy depending on the parameters used. This dose may be multiplied by a factor of ∼8 if no metallic filter is used. However, this dose estimate cannot be universally extrapolated to any µCT-scan experiment but has instead to be specifically assessed for each device and set of parameters employed. The impact on the ESR age results is directly dependent on the magnitude of the geological dose measured in fossil enamel but could potentially lead to an age overestimation up to 40% in case of Late Pleistocene samples, if not taken into consideration. © 2017 Wiley Periodicals, Inc.

  16. Therapeutic impact of CT-guided percutaneous catheter drainage in treatment of deep tissue abscesses

    Energy Technology Data Exchange (ETDEWEB)

    Asai, Nobuhiro; Ohkuni, Yoshihiro; Kaneko, Norihiro; Aoshima, Masahiro; Yamazaki, Ikuo; Kawamura, Yasutaka, E-mail: nobuhiro0204@hotmail.com [Kameda Medical Center, Chiba (Japan)

    2013-03-15

    Combination therapy of CT-guided percutaneous drainage and antibiotics is the first-line treatment for abscesses. Its effectiveness has been demonstrated. However, the therapeutic impact of this procedure for infection treatment has never been reported. We retrospectively analyzed all 47 patients who received CT-guided percutaneous drainage for infection treatment. Patients' characteristics, pathogens isolated, antibiotics administered, technical and clinical outcomes, complications related to this procedure and therapeutic impacts were investigated. Patients were 26 males and 21 females. The mean age was 63.5 years ({+-}18.7). The diseases targeted were 19 retroperitoneal abscesses, 18 intraabdominal abscesses, three pelvic abscesses, and seven others. As for technical outcomes, all of the 54 procedures (100%) were successful. As for clinical outcomes, 44 (93.6%) were cured and three patients (6.4%) died. No complications related to this procedure were found in this study. A total of 42 patients (88%) had a change in the management of their infection as a result of CT-guided percutaneous drainage, such as selection and discontinuation of antibiotics. In conclusion, CT-guided percutaneous drainage is a safe and favorable procedure in the treatment of deep tissue abscesses. Therapeutic impact of these procedures helped physicians make a rational decision for antibiotics selection. (author)

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

    International Nuclear Information System (INIS)

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

    2002-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-01-01

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

  19. Serial CT and MRI of ischaemic cerebral infarcts: frequency and clinical impact of haemorrhagic transformation

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, T.E.; Brueckmann, H. [Muenchen Univ. (Germany). Abt. fuer Neuroradiologie; Schulte-Altedorneburg, G. [Dept. of Radiology/Neuroradiology, University Medical School of Luebeck (Germany); Droste, D.W. [Dept. of Neurology, University Medical School of Luebeck (Germany)

    2000-04-01

    The frequency, predisposing factors and clinical consequences of haemorrhagic infarcts and damaged blood-brain barrier as shown by contrast enhancement (CE) in ischaemic cerebral infarcts are controversial. We prospectively compared the sensitivity of CT and MRI to haemorrhagic transformation (HT) and CE. We also wished to investigate the clinical significance of HT and factors possibly associated with it. We studied 36 patients with acute ischaemic infarcts in the middle cerebral artery territory during the first 2 weeks after the ictus. After CT and rating of the neurological deficit on admission, serial examinations with clinical neuromonitoring, contrast-enhanced CT and MRI were done on the same day. The occurrence and severity of HT were correlated with CE, stroke mechanism, infarct size, development of neurological deficits and antithrombotic treatment. The frequency of HT detected by MRI was 80 %. CE usually preceded HT or was seen simultaneously. MRI had a higher sensitivity than CT to HT and CE. Severity of HT was positively correlated with infarct size (P < 0.01). HT had no influence on patient's neurological status. Neither the type of antithrombotic treatment nor the stroke mechanism was associated with the severity of HT. No parenchymal haemorrhage occurred. (orig.)

  20. {sup 18}F-FDG PET/contrast enhanced CT in the standard surveillance of high risk colorectal cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Jiménez Londoño, Germán Andrés, E-mail: gjimenez91@yahoo.com [Department of Nuclear Medicine, Hospital General Universitario de Ciudad Real, Ciudad Real (Spain); García Vicente, Ana María [Department of Nuclear Medicine, Hospital General Universitario de Ciudad Real, Ciudad Real (Spain); Sánchez Pérez, Victoria [Department of Oncology, Hospital General Universitario de Ciudad Real, Ciudad Real (Spain); Jiménez Aragón, Fátima [Department of Radiology, Hospital General Universitario de Ciudad Real, Ciudad Real (Spain); León Martin, Alberto [Investigation Unit, Hospital General Universitario de Ciudad Real, Ciudad Real (Spain); Cano Cano, Juana María [Department of Oncology, Hospital General Universitario de Ciudad Real, Ciudad Real (Spain); Domínguez Ferreras, Esther [Department of Radiology, Hospital General Universitario de Ciudad Real, Ciudad Real (Spain); Gómez López, Ober Van [Department of Nuclear Medicine, Hospital General Universitario de Ciudad Real, Ciudad Real (Spain); Espinosa Arranz, Javier [Department of Oncology, Hospital General Universitario de Ciudad Real, Ciudad Real (Spain); Soriano Castrejón, Ángel María [Department of Nuclear Medicine, Hospital General Universitario de Ciudad Real, Ciudad Real (Spain)

    2014-12-15

    Highlights: • We assessed the accuracy of FDG-PET/contrast enhanced CT (FDG-PET/ceCT) in the detection of unsuspected recurrence of colorectal cancer. In regard to our knowledge, no previous experience has been reported about the combined acquisition and interpretation of a FDG-PET/ceCT in the surveillance of colorectal cancer. • We designed a prospective study and performed an individual and combined assessment of both techniques (PET and ceCT), in a patient-based analysis and a lesion-based analysis. • The value of PET and ceCT was found to be similar in the detection of unsuspected recurrence of CRC in a patient-based analysis. The most interesting of our result, is that the combined assessment of PET/ceCT improves the accuracy in the lesion-based analysis. - Abstract: Objective: To assess the accuracy of FDG-PET/contrast enhanced CT (FDG-PET/ceCT) in the detection of unsuspected recurrence of colorectal cancer (CRC) in patients with high risk of relapse. Methods: Thirty-three patients (14 females and 19 males, mean age: 62, range: 41–78), with CRC in complete remission, were prospectively included. All patients underwent FDG-PET/ceCT (58 studies). FDG-PET/ceCT was requested in the surveillance setting, and performed following a standardized protocol. A portal venous phase CT scan was performed after the injection of iodinated contrast agent. An individual and combined assessment of both techniques (PET and ceCT) was performed. Concordant and discordant findings of PET, ceCT and FDG-PET/ceCT were compared in a patient-based and a lesion-based analysis. The final diagnosis, recurrence or disease free status (DFS), were established by histopathology or clinical/radiological follow-up of at least 6 months. Results: Seven out of 33 patients had a confirmed recurrence and the rest of patients had a DFS. In a patient-based analysis the sensitivity and specificity of PET, ceCT and PET/ceCT was of 86% and 88%, 86% and 92%, 86% and 85%, respectively. Attending to

  1. Accuracy and role of contrast-enhanced CT in diagnosis and surgical planning in 88 soft tissue tumours of extremities

    International Nuclear Information System (INIS)

    Verga, Lucia; Robiati, Sara; De Marchi, Armanda; Martorano, Domenico; Faletti, Carlo; Brach del Prever, Elena Maria; Linari, Alessandra; Boffano, Michele; Piana, Raimondo

    2016-01-01

    Soft tissue tumours (STT) require accurate diagnosis in order to identify potential malignancies. Preoperative planning is fundamental to avoid inadequate treatments. The role of contrast-enhanced computed tomography (CT) for local staging remains incompletely assessed. Aims of the study were to evaluate CT accuracy in discriminating active from aggressive tumours compared to histology and evaluate the role of CT angiography (CTA) in surgical planning. This retrospective cohort series of 88 cases from 1200 patients (7 %) was locally studied by contrast-enhanced CT and CTA in a referral centre: 74 malignant tumours, 14 benign lesions. Contrast-enhancement patterns and relationship of the mass with major vessels and bone were compared with histology on surgically excised samples. Sensitivity, specificity, positive and negative predictive values (PPV, NPV) were evaluated in discriminating active from aggressive tumours. Sensitivity in differentiating aggressive tumours from active lesions was 89 %, specificity 84 %, PPV 90 %, NPV 82 %. The relationship between mass and major vessels/bone was fundamental for surgical strategy respectively in 40 % and in 58 % of malignant tumours. Contrast-enhanced CT and CTA are effective in differentiating aggressive masses from active lesions in soft tissue and in depicting the relationship between tumour and adjacent bones and major vessels. (orig.)

  2. Pediatric chest CT after trauma: impact on surgical and clinical management

    International Nuclear Information System (INIS)

    Patel, Rina P.; Hernanz-Schulman, Marta; Hilmes, Melissa A.; Kan, J.H.; Yu, Chang; Ray, Jackie

    2010-01-01

    Chest CT after pediatric trauma is frequently performed but its clinical impact, particularly with respect to surgical intervention, has not been adequately evaluated. To assess the impact of chest CT compared with chest radiography on pediatric trauma management. Two hundred thirty-five consecutive pediatric trauma patients who had both chest CT and radiography were identified. Images were reviewed and findings were categorized and correlated with subsequent chest interventions, blinded to final outcome and management. Of the 235 children, 38.3% (90/235) had an abnormal chest radiograph and 63.8% (150/235) had an abnormal chest CT (P < 0.0001). Chest interventions followed in 4.7% (11/235); of these, the findings could be made 1 cm above the dome of the liver in 91% (10/11). Findings requiring chest intervention included pneumothorax (PTX) and vertebral fractures. PTX was found on 2.1% (5/235) of chest radiographs and 20.0% (47/235) of chest CTs (P < 0.0001); 1.7% (4/235) of the children received a chest tube for PTX, 0.85% (2/235) seen on chest CT only. Vertebral fractures were present in 3.8% of the children (9/235) and 66.7% (6/9) of those cases were treated with spinal fusion or brace. There were no instances of mediastinal vascular injury. Most intrathoracic findings requiring surgical management in our population were identified in the lower chest and would be included in routine abdominopelvic CT exams; this information needs to be taken into consideration in the diagnostic algorithm of pediatric trauma patients. (orig.)

  3. Pediatric chest CT after trauma: impact on surgical and clinical management

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Rina P. [Vanderbilt University School of Medicine, Nashville, TN (United States); Hernanz-Schulman, Marta; Hilmes, Melissa A.; Kan, J.H. [Vanderbilt University, Department of Radiology and Radiological Sciences, Vanderbilt Children' s Hospital, Nashville, TN (United States); Yu, Chang [Vanderbilt University, Department of Biostatistics, Nashville, TN (United States); Ray, Jackie [Vanderbilt University, Department of Pediatric Surgery, Vanderbilt Children' s Hospital, Nashville, TN (United States)

    2010-07-15

    Chest CT after pediatric trauma is frequently performed but its clinical impact, particularly with respect to surgical intervention, has not been adequately evaluated. To assess the impact of chest CT compared with chest radiography on pediatric trauma management. Two hundred thirty-five consecutive pediatric trauma patients who had both chest CT and radiography were identified. Images were reviewed and findings were categorized and correlated with subsequent chest interventions, blinded to final outcome and management. Of the 235 children, 38.3% (90/235) had an abnormal chest radiograph and 63.8% (150/235) had an abnormal chest CT (P < 0.0001). Chest interventions followed in 4.7% (11/235); of these, the findings could be made 1 cm above the dome of the liver in 91% (10/11). Findings requiring chest intervention included pneumothorax (PTX) and vertebral fractures. PTX was found on 2.1% (5/235) of chest radiographs and 20.0% (47/235) of chest CTs (P < 0.0001); 1.7% (4/235) of the children received a chest tube for PTX, 0.85% (2/235) seen on chest CT only. Vertebral fractures were present in 3.8% of the children (9/235) and 66.7% (6/9) of those cases were treated with spinal fusion or brace. There were no instances of mediastinal vascular injury. Most intrathoracic findings requiring surgical management in our population were identified in the lower chest and would be included in routine abdominopelvic CT exams; this information needs to be taken into consideration in the diagnostic algorithm of pediatric trauma patients. (orig.)

  4. Dual-phase contrast enhancement multi-slice CT in grading pancreatic neuroendocrine tumors

    International Nuclear Information System (INIS)

    Zhou Yan; Liu Jianyu; Zhu Xiang

    2013-01-01

    Objective: To evaluate characteristic clinical and imaging findings of pancreatic neuroendocrine tumors (NET) in dual-phase contrast enhancement MSCT. Methods: The dual-phase contrast enhancement MSCT images of 23 lesions in 20 patients with histologically confirmed pancreatic NET were studied retrospectively. Their clinical presentations, imaging characters as well as the intensities of lesions and normal pancreas in each phase were measured, and the following indices were calculated. First, the absolute enhancement of lesions, including the increasing of CT value of the maximum enhancement area within a tumor in arterial phase, that was named A1 in short, and that of the minimum enhancement area was labeled as A2. The same ROI measured increasing CT values in portal venous phase was labeled as V1 and V2 respectively. Secondly, the relatively enhancement indices comparing with the normal pancreas in the same patient within the same phase were calculated. This included the differences between the maximum, as well as the minimum, enhancement areas of tumors and the normal pancreas in arterial phase, which was named as AP1 and AP2 respectively, and those differences in portal venous phase, which were labeled as VP1 and VP2 respectively. All of the tumors were graded as G1 to G3 according to the WHO classification in 2010. A Kruskal Wallis test were performed to compare differences of tumor diameters and the enhancement indices. The change trend of enhancement indices varying with pathology grading were described. Fisher exact test was used to find differences of clinical and imaging characters. Results: Twenty-three lesions in 20 patients included 13 lesions in grade 1 (G1), 8 in G2, and 2 in G3. Among the 10 patients with G1 NET, 7 of them had no endocrine symptoms, while the other 3 had endocrine symptoms. Six of them had no abdominal pain, while 4 of them complained of it. All of the 10 patients with G1 NET had no hepatic metastasis. Among 8 patients with G2 NET

  5. Dosimetric comparison of stereotactic body radiotherapy using 4D CT and multiphase CT images for treatment planning of lung cancer: Evaluation of the impact on daily dose coverage

    International Nuclear Information System (INIS)

    Wang Lu; Hayes, Shelly; Paskalev, Kamen; Jin Lihui; Buyyounouski, Mark K.; Ma, Charlie C.-M.; Feigenberg, Steve

    2009-01-01

    Purpose: To investigate the dosimetric impact of using 4D CT and multiphase (helical) CT images for treatment planning target definition and the daily target coverage in hypofractionated stereotactic body radiotherapy (SBRT) of lung cancer. Materials and methods: For 10 consecutive patients treated with SBRT, a set of 4D CT images and three sets of multiphase helical CT scans, taken during free-breathing, end-inspiration and end-expiration breath-hold, were obtained. Three separate planning target volumes (PTVs) were created from these image sets. A PTV 4D was created from the maximum intensity projection (MIP) reconstructed 4D images by adding a 3 mm margin to the internal target volume (ITV). A PTV 3CT was created by generating ITV from gross target volumes (GTVs) contoured from the three multiphase images. Finally, a third conventional PTV (denoted PTV conv ) was created by adding 5 mm in the axial direction and 10 mm in the longitudinal direction to the GTV (in this work, GTV = CTV = clinical target volume) generated from free-breathing helical CT scans. Treatment planning was performed based on PTV 4D (denoted as Plan-1), and the plan was adopted for PTV 3CT and PTV conv to form Plan-2 and Plan-3, respectively, by superimposing 'Plan-1' onto the helical free-breathing CT data set using modified beam apertures that conformed to either PTV 3CT or PTV conv . We first studied the impact of PTV design on treatment planning by evaluating the dosimetry of the three PTVs under the three plans, respectively. Then we examined the effect of the PTV designs on the daily target coverage by utilizing pre-treatment localization CT (CT-on-rails) images for daily GTV contouring and dose recalculation. The changes in the dose parameters of D 95 and D 99 (the dose received by 95% and 99% of the target volume, respectively), and the V p (the volume receiving the prescription dose) of the daily GTVs were compared under the three plans before and after setup error correction

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

    International Nuclear Information System (INIS)

    Guo Xing; Ding Wei; Qin Huijuan

    2011-01-01

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

  7. [Injection Pressure Evaluation of the New Venous Catheter with Side Holes for Contrast-enhanced CT/MRI].

    Science.gov (United States)

    Fukuda, Junya; Arai, Keisuke; Miyazawa, Hitomi; Kobayashi, Kyouko; Nakamura, Junpei; Suto, Takayuki; Tsushima, Yoshito

    2018-01-01

    The simulation study was conducted for the new venous catheter with side holes of contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) to evaluate the infusion pressure on four contrast media and several injection speeds. All infusion pressure of the new venous catheter with side holes were less than 15 kg/cm 2 as limitation of extension tube and also reduced the infusion pressure by 15% at the maximum compared to the catheter with single hole. The results suggest that the new venous catheter with side holes can reduce the infusion pressure by power injection of contrast-enhanced CT and MRI.

  8. FDG-avid portal vein tumor thrombosis from hepatocellular carcinoma in contrast-enhanced FDG PET/CT

    Directory of Open Access Journals (Sweden)

    Canh Nguyen

    2015-01-01

    Full Text Available Objective(s: In this study, we aimed to describe the characteristics of portal vein tumor thrombosis (PVTT, complicating hepatocellular carcinoma (HCC in contrast-enhanced FDG PET/CT scan. Methods: In this retrospective study, 9 HCC patients with FDG-avid PVTT were diagnosed by contrast-enhanced fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT, which is a combination of dynamic liver CT scan, multiphase imaging, and whole-body PET scan. PET and CT DICOM images of patients were imported into the PET/CT imaging system for the re-analysis of contrast enhancement and FDG uptake in thrombus, the diameter of the involved portal vein, and characteristics of liver tumors and metastasis. Results: Two patients with previously untreated HCC and 7 cases with previously treated HCC had FDG-avid PVTT in contrast-enhanced FDG PET/CT scan. During the arterial phase of CT scan, portal vein thrombus showed contrast enhancement in 8 out of 9 patients (88.9%. PET scan showed an increased linear FDG uptake along the thrombosed portal vein in all patients. The mean greatest diameter of thrombosed portal veins was 1.8 ± 0.2 cm, which was significantly greater than that observed in normal portal veins (P<0.001. FDG uptake level in portal vein thrombus was significantly higher than that of blood pool in the reference normal portal vein (P=0.001. PVTT was caused by the direct extension of liver tumors. All patients had visible FDG-avid liver tumors in contrast-enhanced images. Five out of 9 patients (55.6% had no extrahepatic metastasis, 3 cases (33.3% had metastasis of regional lymph nodes, and 1 case (11.1% presented with distant metastasis. The median estimated survival time of patients was 5 months. Conclusion: The intraluminal filling defect consistent with thrombous within the portal vein, expansion of the involved portal vein, contrast enhancement, and linear increased FDG uptake of the thrombus extended from liver tumor are

  9. Fluctuations in eGFR in relation to unenhanced and enhanced MRI and CT outpatients

    Energy Technology Data Exchange (ETDEWEB)

    Azzouz, Manal, E-mail: manalazzouz@gmail.com [Department of Diagnostic Radiology, Copenhagen University Hospital Herlev, Herlev Ringvej 75, DK 2730 Herlev (Denmark); Rømsing, Janne [Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen Ø (Denmark); Thomsen, Henrik S. [Department of Diagnostic Radiology, Copenhagen University Hospital Herlev, Herlev Ringvej 75, DK 2730 Herlev (Denmark)

    2014-06-15

    Objective: To study fluctuations in estimated glomerular filtration rate (eGFR) in relation to contrast medium (CM) enhanced magnetic resonance imaging (MRI) and computed tomography (CT) compared to control groups in outpatients. Materials and methods: eGFR was determined right before the imaging procedure and three days later at the department or at the patient's home. The iodine-based and gadolinium-based contrast media were the same as used for all other examinations at the department. Results: A total of 716 patients completed the study. There was a statistically significant, but not clinically relevant rise in eGFR after three days in all four groups. The average eGFR variation was 4.8 ml/min/1.73 m{sup 2}. There were large variations in eGFR between the two measurements in 45.8% of the patients as they had a change greater than ±10 ml/min/1.73 m{sup 2}. Only three patients fulfilled the contrast-induced nephropathy (CIN) requirement when the definition s-creatinine ≥44 μmol/l (0.5 mg/dl) was used. Conclusions: eGFR in outpatients undergoing MRI or CT did vary independently of whether the patient received contrast or not. The findings probably reflect the natural variations in s-creatinine levels. This should be taken into consideration when CIN is studied.

  10. Automatic three-dimensional rib centerline extraction from CT scans for enhanced visualization and anatomical context

    Science.gov (United States)

    Ramakrishnan, Sowmya; Alvino, Christopher; Grady, Leo; Kiraly, Atilla

    2011-03-01

    We present a complete automatic system to extract 3D centerlines of ribs from thoracic CT scans. Our rib centerline system determines the positional information for the rib cage consisting of extracted rib centerlines, spinal canal centerline, pairing and labeling of ribs. We show an application of this output to produce an enhanced visualization of the rib cage by the method of Kiraly et al., in which the ribs are digitally unfolded along their centerlines. The centerline extraction consists of three stages: (a) pre-trace processing for rib localization, (b) rib centerline tracing, and (c) post-trace processing to merge the rib traces. Then we classify ribs from non-ribs and determine anatomical rib labeling. Our novel centerline tracing technique uses the Random Walker algorithm to segment the structural boundary of the rib in successive 2D cross sections orthogonal to the longitudinal direction of the ribs. Then the rib centerline is progressively traced along the rib using a 3D Kalman filter. The rib centerline extraction framework was evaluated on 149 CT datasets with varying slice spacing, dose, and under a variety of reconstruction kernels. The results of the evaluation are presented. The extraction takes approximately 20 seconds on a modern radiology workstation and performs robustly even in the presence of partial volume effects or rib pathologies such as bone metastases or fractures, making the system suitable for assisting clinicians in expediting routine rib reading for oncology and trauma applications.

  11. rCBF in radiation necrosis as measured by xenon-enhanced CT

    International Nuclear Information System (INIS)

    Nakamura, Osamu; Nomura, Kazuhiro; Segawa, Hiromu; Nakagomi, Tadayoshi; Tanaka, Hideki; Yoshimasu, Norio; Takakura, Kintomo.

    1986-01-01

    We experienced a case of radiation necrosis in which the necrosis occurred two and a half years after radiation therapy against craniopharyngioma. In this case, we evaluated the regional cerebral blood flow (rCBF) by means of the Xe-enhanced CT method and studied the change in rCBF in comparison with the rCBF pattern of brain tumors or cerebral infarctions. In general, rCBF decreased in accordance with the low-density area in a conventional CT scan. The decrease in rCBF was most significant in the white matter, but the rCBF in the thinned cortex was also lowered. On the contrary, that of the basal ganglia was almost completely preserved. The rCBF pattern was different from those of brain tumors or diffuse cerebral infarction caused by the occlusion of the main arteries and was thought to be characteristic of radiation necrosis. Differential diagnosis between radiation necrosis and the recurrence of brain tumor has been thought to be difficult, but with this rCBF analysis the possibility of differential diagnosis between the two lesions was clearly indicated. (author)

  12. Gadopentate dimeglumine enhanced MR angiography (MRA) for staging AAA: a correlation with DSA and CT

    International Nuclear Information System (INIS)

    Arlart, I.P.; Gerlach, A.; Kolb, M.; Erpenbach, S.; Wuerstlin, S.

    1997-01-01

    Purpose: To evaluate a contrast-enhanced (CE) MRA sequence for staging AAA. Methods: In 24 patients (male=20, female=4, age=44-81 y) with known AAA the abdominal aorta and its branches including the iliac arteries were imaged, using a 3D GRE-FISP sequence (1.5 T, T R /T E /FA=25/6/35, slab=100-140 mm, 32 part., FOV=440-450 mm, matrix=256x256) during an i.v. infusion of 40 ml of gadopentate dimeglumine. In addition, representative axial single slices (2D breathhold FLASH-sequence: T R /T E /FA=82/5/30) were acquired following contrast application. MR-results were correlated with i.a. DSA and CT studies. Results: With CE-MRA, AAA (n=24) and iliac aneurysms (n=17) could be evaluated in all cases (sens.=100%, spec.=100%) including luminal patency and mural thrombus. 50/54 renal arteries could be identified, 4/6 accessory renal arteries (sens=66,6%, spec.=100%), 8/9 renal artery stenoses>50% (sens.=88.8%, spec.=89.3%), 1/1 renal artery occlusion and 7/8 iliac artery stenoses>50% (sens.=87.5%, spec.=97.5%) were depicted correctly. Proximal portion of sup. mes. art. could be detected and evaluated in 21/24 cases. Quantitative determination of therapeutically relevant vascular paramters using MRA was comparable to DSA and CT. (orig./AJ) [de

  13. Fluctuations in eGFR in relation to unenhanced and enhanced MRI and CT outpatients

    International Nuclear Information System (INIS)

    Azzouz, Manal; Rømsing, Janne; Thomsen, Henrik S.

    2014-01-01

    Objective: To study fluctuations in estimated glomerular filtration rate (eGFR) in relation to contrast medium (CM) enhanced magnetic resonance imaging (MRI) and computed tomography (CT) compared to control groups in outpatients. Materials and methods: eGFR was determined right before the imaging procedure and three days later at the department or at the patient's home. The iodine-based and gadolinium-based contrast media were the same as used for all other examinations at the department. Results: A total of 716 patients completed the study. There was a statistically significant, but not clinically relevant rise in eGFR after three days in all four groups. The average eGFR variation was 4.8 ml/min/1.73 m 2 . There were large variations in eGFR between the two measurements in 45.8% of the patients as they had a change greater than ±10 ml/min/1.73 m 2 . Only three patients fulfilled the contrast-induced nephropathy (CIN) requirement when the definition s-creatinine ≥44 μmol/l (0.5 mg/dl) was used. Conclusions: eGFR in outpatients undergoing MRI or CT did vary independently of whether the patient received contrast or not. The findings probably reflect the natural variations in s-creatinine levels. This should be taken into consideration when CIN is studied

  14. Dosimetric impact of image artifact from a wide-bore CT scanner in radiotherapy treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Vincent; Podgorsak, Matthew B.; Tran, Tuan-Anh; Malhotra, Harish K.; Wang, Iris Z. [Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 and Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, New York 14214 (United States); Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 and Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, New York 14214 (United States)

    2011-07-15

    Purpose: Traditional computed tomography (CT) units provide a maximum scan field-of-view (sFOV) diameter of 50 cm and a limited bore size, which cannot accommodate a large patient habitus or an extended simulation setup in radiation therapy (RT). Wide-bore CT scanners with increased bore size were developed to address these needs. Some scanners have the capacity to reconstruct the CT images at an extended FOV (eFOV), through data interpolation or extrapolation, using projection data acquired with a conventional sFOV. Objects that extend past the sFOV for eFOV reconstruction may generate image artifacts resulting from truncated projection data; this may distort CT numbers and structure contours in the region beyond the sFOV. The purpose of this study was to evaluate the dosimetric impact of image artifacts from eFOV reconstruction with a wide-bore CT scanner in radiotherapy (RT) treatment planning. Methods: Testing phantoms (i.e., a mini CT phantom with equivalent tissue inserts, a set of CT normal phantoms and anthropomorphic phantoms of the thorax and the pelvis) were used to evaluate eFOV artifacts. Reference baseline images of these phantoms were acquired with the phantom centrally positioned within the sFOV. For comparison, the phantoms were then shifted laterally and scanned partially outside the sFOV, but still within the eFOV. Treatment plans were generated for the thoracic and pelvic anthropomorphic phantoms utilizing the Eclipse treatment planning system (TPS) to study the potential effects of eFOV artifacts on dose calculations. All dose calculations of baseline and test treatment plans were carried out using the same MU. Results: Results show that both body contour and CT numbers are altered by image artifacts in eFOV reconstruction. CT number distortions of up to -356 HU for bone tissue and up to 323 HU for lung tissue were observed in the mini CT phantom. Results from the large body normal phantom, which is close to a clinical patient size, show

  15. [Application of Low Dose Spiral CT in Diagnosing Impacted Teeth in Children and Adolescents].

    Science.gov (United States)

    Wang, Meng-tian; Li, Xue-sheng; Li, Kai-ming; Bao, Li; Ning, Gang

    2015-09-01

    [ABSTRACT] To determine the value of low dose spiral CT scanning in diagnosing impacted teeth of children and adolescents. A total of 153 children and adolescents with confirmed impacted teeth in West China Second University Hospital, Sichuan University were enrolled in this study. They were divided into 5 groups according to the different spiral CT scan parameters (tube current time product, scanning thickness and collimation value): Group A (n=30, 330 mAs, 6 X 0. 75 mm and 3. 0 mm), Group B (n=30, 140 mAs, 6 X 0. 75 mm and 3. 0 mm), Group C (n=30, 80 mAs, 6 X 0. 75 mm and 3. 0 mm), Group D (n=31, 80 mAs, 6 X 1. 50 mm and 5. 0 mm), and Group E (n=32, 50 mAs, 6 X 1. 50 mm and 5. 0 mm). There were no significant differences in general clinical features (P>0. 05) among the participants of the five groups. The phantoms were used to measure spatial resolution and contrast resolution of the scan images. Dose length product (DLP) was recorded during CT scanning for calculating effective dose (ED) of exposure. The quality of images was evaluated using a list of quality scoring criteria. (1) Under 330, 140, 80, 80 and 50 mAs, the images had a spatial resolution of 1.0 mm, with contrast resolution of 2. 0, 3. 0, 4. 5, 4. 5 and 6. 0 mm, respectively. (2) Significant differences in ED values were found among the five groups (F=1 064. 119, P=0. 000) and between every two of those groups (P0. 05). The diagnostic results of the spiral CT were consistent with those of orthodontic surgery. Low dose spiral CT scanning can meet the image quality requirements for diagnosing impacted teeth, minimizing radiation exposure effectively.

  16. Arterio-venous anastomoses in mice affect perfusion measurements with dynamic contrast enhanced CT

    International Nuclear Information System (INIS)

    Gabra, Peter; Lee, Ting-Yim; Shen, Gang; Xuan, Jim

    2010-01-01

    Accurate measurement of perfusion with dynamic contrast enhanced CT requires an arterial input curve (AIC) uncontaminated by venous sources. Arterio-venous anastomoses (AVAs) are sources of contamination if contrast is injected intravenously. We seek to identify AVAs in mice and associated errors in perfusion measurements. Six transgenic mice with spontaneous prostate tumor were scanned with a micro-CT scanner (GE Healthcare (GE)) using a high resolution anatomical and a lower resolution perfusion protocol. For the anatomical protocol, a CT scan was performed during injection of an iodinated contrast agent (Hypaque) into a tail vein. Images covering the thoracic, abdominal and pelvic regions at an isotropic resolution of 175 µm were reconstructed and rendered in 3D to show the arterial and venous tree (Advantage Window, GE). For the perfusion protocol, each mouse was continuously scanned for 40 s and the contrast agent (Hypaque) was injected via a tail vein 5 s into scanning. Tumor images were reconstructed every second. Tumor blood flow (BF) and volume (BV) maps were calculated with CT perfusion software (GE) using AIC measured either from abdominal aorta (AA) or tail (caudal) artery (TA). In all mice, there was an AVA from the bifurcation of the inferior vena cava to the tail artery shunting venous blood and portion of the contrast agent injected into the tail vein into the TA. Contrast arrival time at the TA preceded that at the AA by 3.3 ± 0.5 s (P < 0.05). Mean tumor BV and BF values calculated with AA versus TA were 10.0 ± 1.8 versus 4.8 ± 2.1 ml (100 g) −1 (P < 0.05) and 108.8 ± 26.5 versus 33.0 ± 8.5 ml min −1 100 g −1 (P < 0.05), respectively. AVA in the murine pelvic region can result in inaccurate and more variable measurements of pelvic organ/tissue perfusion when the tail artery is used as the AIC

  17. Appearance and impact of post-operative intracranial clips and coils on whole-brain CT angiography and perfusion

    International Nuclear Information System (INIS)

    Roach, Cayce J.; Russell, Cheryl L.; Hanson, Eric H.; Bluett, Brent; Orrison, William W.

    2012-01-01

    Background: To evaluate the effect of vascular clips and endovascular coils placed for intracranial aneurysms and arteriovenous malformations on whole-brain computed tomography (CT) angiography and perfusion. Methods: A 320-detector row dynamic volume CT system imaged 11 patients following surgical placement of vascular clips or endovascular coils. The extent of clip and coil subtraction by automated software was evaluated using CT digital subtraction angiography and CT perfusion. Impact on CT perfusion values by retained intracranial devices was compared to age- and gender-matched controls. Results: Clip and coil subtraction on CT angiography was graded as good in 8 and moderate in 3 cases. A residual neck and additional aneurysm were noted in 1 of 11 patients. Post-procedural axial slice level CT perfusion values decreased in reliability with increasing proximity to the metallic devices secondary to beam hardening. However, the intracranial devices did not affect axial slice level CTP values of cerebral blood volume, cerebral blood flow and mean transit time outside of the level of the device. Time to peak values was globally decreased outside of the immediate vascular intervention region. Conclusions: Advances in CT technology have provided clinically useful subtraction of intracranial clips and coils. While CT perfusion values were altered in device subtraction areas and within beam hardening artifact areas; they can provide valuable postoperative information on whole-brain hemodynamics. In selected cases, the combination of CT angiography and whole-brain CT perfusion can offer an alternative to conventional angiography that is a more invasive option.

  18. The clinical impact of {sup 18}F-FDG PET/CT in extracranial pediatric germ cell tumors

    Energy Technology Data Exchange (ETDEWEB)

    Hart, Adam; Vali, Reza; Marie, Eman; Shammas, Amer [The Hospital for Sick Children and University of Toronto, Department of Medical Imaging, Nuclear Medicine, Toronto, ON (Canada); Shaikh, Furqan [The Hospital for Sick Children and University of Toronto, Division of Haematology and oncology, Toronto, ON (Canada)

    2017-10-15

    Extracranial germ cell tumors are an uncommon pediatric malignancy with limited information on the clinical impact of {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the literature. The purpose of this study was to evaluate and compare the clinical impact on management of {sup 18}F-FDG PET/CT with diagnostic computed tomography (CT) in pediatric extracranial germ cell tumor. The list of {sup 18}F-FDG PET/CT performed for extracranial germ cell tumor between May 2007 and November 2015 was obtained from the nuclear medicine database. {sup 18}F-FDG PET/CT and concurrent diagnostic CT were obtained and independently reviewed. Additionally, the patients' charts were reviewed for duration of follow-up and biopsy when available. The impact of {sup 18}F-FDG PET/CT compared with diagnostic CT on staging and patient management was demonstrated by chart review, imaging findings and follow-up studies. During the study period, 9 children (5 males and 4 females; age range: 1.6-17 years, mode age: 14 years) had 11 {sup 18}F-FDG PET/CT studies for the evaluation of germ cell tumor. Diagnostic CTs were available for comparison in 8 patients (10 {sup 18}F-FDG PET/CT studies). The average interval between diagnostic CT and PET/CT was 7.2 days (range: 0-37 days). In total, five lesions concerning for active malignancy were identified on diagnostic CT while seven were identified on PET/CT. Overall, {sup 18}F-FDG PET/CT resulted in a change in management in 3 of the 9 patients (33%). {sup 18}F-FDG PET/CT had a significant impact on the management of pediatric germ cell tumors in this retrospective study. Continued multicenter studies are required secondary to the rarity of this tumor to demonstrate the benefit of {sup 18}F-FDG PET/CT in particular clinical scenarios. (orig.)

  19. The significance of delayed contrast-enhanced CT in chronic subdural hematomas

    International Nuclear Information System (INIS)

    Karasawa, Hideharu; Ohya, Shigeru; Ueno, Junji; Watanabe, Saburo; Mikabe, Toshio

    1983-01-01

    We have previously, reported our delayed contrast-enhanced CT (DCECT) findings in traumatic subdural hygromas and chronic subdural hematomas. The purpose of this report is to clarify the relationship between the contrast media within subdural hematomas and the delayed enhancement. The clinical subjects were 35 cases of traumatic subdural hematomas. DCECT examinations were performed in all cases. The concentrations of the contrast media within the hematoma were measured during the operations. DCECT showed that the density of the hematomas increased 3 to 6 hours after the injection of the contrast media. The contrast media were detected within the hematomas a few hours after the injection. The contrast media were still present 24 hours after the injection, but disappeared in 48 hours. These findings suggest that contrast media go in and then come out of the subdural hematomas and that the main factor related to delayed enhancement is the concentration of the contrast media within the hematomas. DCECT examination may be most helpful in evaluating the dynamic changes in subdural collections. (author)

  20. Multiple renal aspergillus abscesses in an AIDS patient: contrast-enhanced helical CT and MRI findings

    International Nuclear Information System (INIS)

    Heussel, C.P.; Kauczor, H.U.; Thelen, M.; Heussel, G.; Jahn, B.

    1999-01-01

    Renal insufficiency or allergic reactions for X-ray contrast agents are frequent limitations in immunocompromised hosts such as neutropenic or AIDS patients. Due to a better tolerance of contrast agents in MRI, this technique is well suited for investigation of parenchymal organs. We demonstrate an allergic AIDS patient who presented with fever and flank pain. At sonography, anechoic renal lesions were supposed to be non-complicated cysts; however, on T2-weighted MRI, the center was of high signal. Dynamic contrast-enhanced MRI of the kidneys demonstrated an enhancing rim with ill-defined margins. The lesions were supposed to be multiple bilateral abscesses. Due to the multiple dynamic contrast series, a delayed enhancement of renal parenchyma was detectable adjacent to the lesion. This was suggested as accompanying local pyelonephritis and an infectious etiology became more reliable. Aspergillus fumigatus was identified by CT-guided biopsy as the underlying microorganism. The MR appearance of this manifestation has not been described previously. (orig.)

  1. Interstitial Features at Chest CT Enhance the Deleterious Effects of Emphysema in the COPDGene Cohort.

    Science.gov (United States)

    Ash, Samuel Y; Harmouche, Rola; Ross, James C; Diaz, Alejandro A; Rahaghi, Farbod N; Sanchez-Ferrero, Gonzalo Vegas; Putman, Rachel K; Hunninghake, Gary M; Onieva, Jorge Onieva; Martinez, Fernando J; Choi, Augustine M; Bowler, Russell P; Lynch, David A; Hatabu, Hiroto; Bhatt, Surya P; Dransfield, Mark T; Wells, J Michael; Rosas, Ivan O; San Jose Estepar, Raul; Washko, George R

    2018-06-05

    Purpose To determine if interstitial features at chest CT enhance the effect of emphysema on clinical disease severity in smokers without clinical pulmonary fibrosis. Materials and Methods In this retrospective cohort study, an objective CT analysis tool was used to measure interstitial features (reticular changes, honeycombing, centrilobular nodules, linear scar, nodular changes, subpleural lines, and ground-glass opacities) and emphysema in 8266 participants in a study of chronic obstructive pulmonary disease (COPD) called COPDGene (recruited between October 2006 and January 2011). Additive differences in patients with emphysema with interstitial features and in those without interstitial features were analyzed by using t tests, multivariable linear regression, and Kaplan-Meier analysis. Multivariable linear and Cox regression were used to determine if interstitial features modified the effect of continuously measured emphysema on clinical measures of disease severity and mortality. Results Compared with individuals with emphysema alone, those with emphysema and interstitial features had a higher percentage predicted forced expiratory volume in 1 second (absolute difference, 6.4%; P < .001), a lower percentage predicted diffusing capacity of lung for carbon monoxide (DLCO) (absolute difference, 7.4%; P = .034), a 0.019 higher right ventricular-to-left ventricular (RVLV) volume ratio (P = .029), a 43.2-m shorter 6-minute walk distance (6MWD) (P < .001), a 5.9-point higher St George's Respiratory Questionnaire (SGRQ) score (P < .001), and 82% higher mortality (P < .001). In addition, interstitial features modified the effect of emphysema on percentage predicted DLCO, RVLV volume ratio, 6WMD, SGRQ score, and mortality (P for interaction < .05 for all). Conclusion In smokers, the combined presence of interstitial features and emphysema was associated with worse clinical disease severity and higher mortality than was emphysema alone. In addition, interstitial features

  2. Patients with liver FNH and HCC patients with negative AFP: plain and dynamic enhanced MRI and CT findings

    Directory of Open Access Journals (Sweden)

    LI Mingtong

    2015-05-01

    Full Text Available ObjectiveTo investigate plain and dynamic enhanced magnetic resonance imaging (MRI and computed tomography (CT findings in patients with focal nodular hyperplasia (FNH of the liver and hepatocellular carcinoma (HCC patients with negative alpha-fetoprotein (AFP. MethodsA statistical analysis was performed on the clinical data of 124 cases of liver tumor admitted to Beijing Miyun County Hospital from April 2012 to April 2014. ResultsFifty-five of the 74 patients with FNH underwent CT examination, among whom 38 patients received three-phase dynamic enhanced scan and 16 received only plain scan; 62 cases had plain and enhanced MRI with the application of contrast agent Gd-BOPTA in 42 patients. Among the 50 HCC patients with negative AFP, CT examination was performed in 40 and 10 only had plain scan; 46 patients received plain and enhanced MRI with the use of contrast agent Gd-BOPTA in 30. Delayed scan after 1-2 h demonstrated low signal in 30 lesions of the 30 cases. ConclusionFor patients with liver FNH and AFP-negative HCC patients, their plain and dynamic enhanced MRI and CT scan have respective characteristics. A combination of multiple examination methods can significantly improve diagnostic yield of the two diseases.

  3. Chondroitin sulfate iron colloid-enhanced MR imaging in patients with hepatocellular carcinoma. Comparison with CT during arterial portography

    Energy Technology Data Exchange (ETDEWEB)

    Kamba, Masayuki [Dept. of Radiology, Tottori Univ., Yonago (Japan); Suto, Y. [Dept. of Radiology, Tottori Univ., Yonago (Japan); Kato, T. [Dept. of Radiology, Tottori Univ., Yonago (Japan)

    1994-11-01

    Chondroitin sulfate iron colloid (CSIC) was used as an MR contrast agent for the detection of hepatocellular carcinoma (HCC). The findings of 25 surgically confirmed HCCs in 19 patients were retrospectively analyzed. T1-, T2- and proton density-weighted spin echo MR images were obtained before and after i.v. injection of 23.6 {mu}M Fe/kg of CSIC. Unenhanced and CSIC-enhanced MR images and images obtained by CT during arterial protography (CT-AP) were correlated with surgical pathology findings. The sensitivities of CSIC-enhanced and unenhanced MR imaging, and CT-AP were 92%, 80%, and 88%, respectively. No significant differences were noted. Portal flow abnormalities demonstrated by CT-AP did not affect the detection of HCC by CSIC-enhanced MR imaging. CSIC-enhancement at MR imaging was a disadvantage in the detection of lesions less than 1 cm in diameter. CSIC-enhanced MR imaging is a supplemental method for the detection of HCC. (orig.).

  4. Blunt renal trauma: comparison of contrast-enhanced CT and angiographic findings and the usefulness of transcatheter arterial embolization

    International Nuclear Information System (INIS)

    Kitase, M.; Mizutani, M.; Tomita, H.; Kono, T.; Sugie, C.; Shibamoto, Y.

    2007-01-01

    Full text: Background: The purpose of this study was to evaluate the role of contrast-enhanced CT and the usefulness of super selective embolization therapy in the management of arterial damage in patients with severe blunt renal trauma. Patients and Methods: Nine cases of severe renal trauma were evaluated. In all cases, we compared contrast enhanced CT findings with angiographic findings, and performed transcatheter arterial embolization (TAE) in six of them with microcoils and gelatin sponge particles. Morphological changes in the kidney and site of infarction after TAE were evaluated on follow-up CT Chronological changes in blood biochemistry findings after injury, degree of anemia and renal function were investigated. Adverse effects or complications such as duration of hematuria, fever, abdominal pain, renovascular hypertension and abscess formation were also evaluated. Results: The CT finding of extravasation was a reliable sign of active bleeding and useful for determining the indication of TAE. In all cases, bleeding was effectively controlled with super selective embolization. There was minimal procedure-related loss of renal tissue. None of the patients developed abscess, hypertension or other complications. Conclusions: In blunt renal injury, contrast-enhanced CT was useful for diagnosing arterial hemorrhage. Arterial bleeding may produce massive hematoma and TAE was a useful treatment for such cases. By using selective TAE for a bleeding artery, it was possible to minimize renal parenchymal damage, with complications of TAE rarely seen. (author)

  5. 18F-FDG PET/contrast enhanced CT in the standard follow-up of patients with lymphoma.

    Science.gov (United States)

    García Vicente, A M; Talavera Rubio, M P; Dominguez Ferreras, E; Calle Primo, C; Amo-Salas, M; Tello Galán, M J; Jiménez Londoño, G A; Jiménez Aragón, F; Hernández Ruiz, B; Soriano Castrejón, Á

    To assess the diagnostic accuracy of 18 F-FDG PET/contrast enhanced computed tomography (ceCT) in the detection of asymptomatic recurrences in patients with lymphoma. Patients with lymphoma and clinical complete remission underwent 18 F-FDG PET/ceCT for standard follow-up. 18 F-FDG PET and ceCT were evaluated blindly by two independent observers, and classified as positive or negative for recurrence. Additionally a combined evaluation of both techniques was performed. The final diagnosis was established by histopathological analysis or a clinical follow-up longer than 6 months. Statistical diagnostic parameters and concordance levels between both diagnostic techniques were calculated. A total of 114 explorations on 90 patients were analyzed. Only 4 patients were diagnosed as asymptomatic recurrence during the follow-up. 18 F-FDG PET/ceCT, 18 F-FDG PET and ceCT showed an association with the final diagnosis (p=0.002 and χ 2 =11.96; p<0.001 and χ 2 =15.60; p=0.001 and χ 2 =11.96, respectively). The concordance between 18 F-FDG PET and ceCT was moderate/high and significant (kappa=0.672; p<0.001). A sensitivity and specificity of 50% and 88% was obtained for the 18 F-FDG PET/ceCT civ, 50% and 93% for the 18 F-FDG PET, and 50% and 91% for the ceCT. The combined use of 18 F-FDG PET/ceCT did not offer any advantage compared to any isolated diagnostic technique in the detection of asymptomatic lymphoma recurrence. Copyright © 2017 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

  6. 18F-Fluorodeoxyglucose PET/CT and dynamic contrast-enhanced MRI as imaging biomarkers in malignant pleural mesothelioma.

    Science.gov (United States)

    Hall, David O; Hooper, Clare E; Searle, Julie; Darby, Michael; White, Paul; Harvey, John E; Braybrooke, Jeremy P; Maskell, Nick A; Masani, Vidan; Lyburn, Iain D

    2018-02-01

    The purpose of this study was to compare the use of fluorine-18-fluorodeoxyglucose (F-FDG) PET with computed tomography (CT) and dynamic contrast-enhanced (DCE) MRI to predict prognosis and monitor treatment in malignant pleural mesothelioma. F-FDG PET/CT and DCE-MRI studies carried out as part of the South West Area Mesothelioma Pemetrexed trial were used. F-FDG PET/CT and DCE-MRI studies were carried out before treatment, and after two cycles of chemotherapy, on patients treated with pemetrexed and cisplatin. A total of 73 patients were recruited, of whom 65 had PET/CT and DCE-MRI scans. Baseline measurements from F-FDG PET/CT (maximum standardized uptake value, metabolic tumour volume and total lesion glycolysis) and DCE-MRI (integrated area under the first 90s of the curve and washout slope) were compared with overall survival (OS) using Kaplan-Meier and Cox regression analyses, and changes in imaging measurements were compared with disease progression. PET/CT and DCE-MRI measurements were not correlated with each other. Maximum standardized uptake value, metabolic tumour volume and total lesion glycolysis were significantly related to OS with Cox regression analysis and Kaplan-Meir analysis, and DCE-MRI washout curve shape was significantly related to OS. DCE-MRI curve shape can be combined with F-FDG PET/CT to give additional prognostic information. Changes in measurements were not related to progression-free survival. F-FDG PET/CT and DCE-MRI give prognostic information in malignant pleural mesothelioma. Neither PET/CT nor DCE-MRI is useful for monitoring disease progression.

  7. Primary pulmonary low-grade angiosarcoma characterized by mismatch between {sup 18}F-FDG FET and dynamic contrast-enhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    KIm, Eun Young; Lee, Ho Yun; Han, Joung Ho; Choi, Joon Young [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2015-10-15

    We report a rare case of primary pulmonary low-grade angiosarcoma on dynamic contrast-enhanced CT and {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT imaging. A 38-year-old, asymptomatic woman was hospitalized because of an abnormality on chest radiography. A dynamic contrast-enhanced chest CT showed a 1.2 cm-sized irregular-margined nodule with strong and persistent enhancement in the right lower lobe. The lesion had low metabolic activity on an {sup 18}F-FDG PET/CT scan. The patient underwent a wedge resection for the lesion, and pathology revealed a primary pulmonary low-grade angiosarcoma.

  8. Study of effect of different CT scanning protocols on HU variation and their impact on TPS calculations

    International Nuclear Information System (INIS)

    Mahur, Mamta; Sharma, Richa; Sasindaran, M.; Singh, Anshu; Gedam, Varsha; Negi, P.S.; Grover, R.K.

    2016-01-01

    Computer tomographic (CT) scans are used to correct for tissue inhomogeneties in radiotherapy treatment planning. In order to guarantee a precise treatment, it is important to obtain the relationship between CT Hounsfield units and relative electron densities, which is the basic input for radiotherapy planning systems which consider tissue heterogeneities. The purpose of this study is to investigate the influence of different CT scan parameters (kVp, mAs) on uniformity of CT numbers versus relative electron density (HURED) curves and their different dosimetric impact

  9. Contrast-enhanced multislice pneumo-CT-cystography in the evaluation of urinary bladder neoplasms

    Energy Technology Data Exchange (ETDEWEB)

    Scardapane, Arnaldo [Institute of Diagnostic Radiology, University Hospital ' Policlinico' , Bari (Italy)], E-mail: scardapane@aruba.it; Pagliarulo, Vincenzo [Institute of Urology, University Hospital ' Policlinico' , Bari (Italy); Ianora, Amato A. Stabile [Institute of Diagnostic Radiology, University Hospital ' Policlinico' , Bari (Italy); Pagliarulo, Arcangelo [Institute of Urology, University Hospital ' Policlinico' , Bari (Italy); Angelelli, Giuseppe [Institute of Diagnostic Radiology, University Hospital ' Policlinico' , Bari (Italy)

    2008-05-15

    Purpose: To evaluate the accuracy of contrast-enhanced multislice CT (MSCT) in the study of urothelial tumors after distension of the bladder with air. Materials and methods: We evaluated 43 consecutive patients with endoscopically proven bladder lesions. After air distension of the bladder, unenhanced pelvic and enhanced abdomino-pelvic scans were obtained with the following protocol: thickness 2.5 mm x 4 mm, increment 1 mm, scan delay 40'' and 7-10 min. For each patient we considered the number, size, aspect (papillary or sessile) and contrast enhancement of lesions. Ureteral involvement and the presence of synchronous lesions in the excretory scan were also evaluated. MPR and virtual endoscopy images were reviewed in all cases. Results: Bladder lesions were visualized in 39/43 cases. Compared to conventional cystoscopy, MSCT recognized single lesions in 31/33 patients, two lesions in 4/6, three in 2/2 and more than five foci in 2/2 patients. A papillary aspect was described in 44 cases while 11 lesions were sessile. Conventional Cystoscopy recognized six more lesions as compared with MSCT (four flat and two small papillary lesions). The detection rate for protruding lesions was 100% (52/52) for lesions > 5 mm and 60% (3/5%) for lesions < 5 mm. In four patients hydronephrosis was present, while in one case a synchronous lesion was evident in the renal pelvis. Conclusion: Contrast-enhanced MSCT with air distension of the urinary bladder is a safe and complete investigation to evaluate the local stage of bladder cancer and to evaluate the ureteral extension of the tumor, as well as the presence of synchronous lesions.

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

    Science.gov (United States)

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

    2017-08-01

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

  11. The impact of radiologists' expertise on screen results decisions in a CT lung cancer screening trial

    International Nuclear Information System (INIS)

    Heuvelmans, Marjolein A.; Vliegenthart, Rozemarijn; Oudkerk, Matthijs; Jong, Pim A. de; Mali, Willem P.; Groen, Harry J.M.

    2015-01-01

    To evaluate the impact of radiological expertise on screen result decisions in a CT lung cancer screening trial. In the NELSON lung cancer screening trial, the baseline CT result was based on the largest lung nodule's volume. The protocol allowed radiologists to manually adjust screen results in cases of high suspicion of benign or malignant nodule nature. Participants whose baseline CT result was based on a solid or part-solid nodule were included in this study. Adjustments by radiologists at baseline were evaluated. Histology was the reference for diagnosis or to confirm benignity and stability on subsequent CT examinations. A total of 3,318 participants (2,796 male, median age 58.0 years) were included. In 195 participants (5.9 %) the initial baseline screen result was adjusted by the radiologist. Adjustment was downwards from positive or indeterminate to negative in two and 119 participants, respectively, and from positive to indeterminate in 65 participants. None of these nodules turned out to be malignant. In 9/195 participants (4.6 %) the screen result was adjusted upwards from negative to indeterminate or indeterminate to positive; two nodules were malignant. In one in 20 cases of baseline lung cancer screening, nodules were reclassified by the radiologist, leading to a reduction of false-positive screen results. (orig.)

  12. Dual-energy CT for detection of contrast enhancement or leakage within high-density haematomas in patients with intracranial haemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Yoshiyuki; Tsukabe, Akio; Kunitomi, Yuki; Nishizawa, Mitsuo; Arisawa, Atsuko; Tanaka, Hisashi; Tomiyama, Noriyuki [Osaka University Graduate School of Medicine, Department of Diagnostic and Interventional Radiology, Suita, Osaka (Japan); Yoshiya, Kazuhisa; Shimazu, Takeshi [Osaka University Graduate School of Medicine, Department of Traumatology and Acute Critical Medicine, Osaka (Japan)

    2014-04-15

    Our study aimed to elucidate the diagnostic performance of dual-energy CT (DECT) in the detection of contrast enhancement in intracranial haematomas (ICrH) with early phase dual-energy computed tomography angiography (CTA) and compare the results with those obtained by delayed CT enhancement. Thirty-six patients with ICrH were retrospectively included in this study. All patients had undergone single-energy non-contrast CT and contrast-enhanced dual-source DECT. DECT images were post-processed with commercial software, followed by obtaining iodine images and virtual non-contrast images and generating combined images that created the impression of 120-kVp images. Two neuroradiologists, blinded to the patients' data, reviewed two reading sessions: session A (non-contrast CT and combined CT) and session B (non-contrast CT, combined CT, and iodine images) for detection of contrast enhancement in the haematomas. Contrast leakage or enhancement was detected in 23 (57.5 %) out of 40 haemorrhagic lesions in 36 patients on delayed CT. Three enhanced lesions were depicted only in the DECT iodine images. The sensitivity, specificity, positive predictive value, and negative predictive value of session A were 82.6, 94.1, 95.0, and 80.0 %, respectively, and those of session B were 95.7, 94.1, 95.7, and 94.1 %, respectively. DECT emphasised the iodine enhancement and facilitated the detection of contrast enhancement or leakage. (orig.)

  13. Dual-energy CT for detection of contrast enhancement or leakage within high-density haematomas in patients with intracranial haemorrhage.

    Science.gov (United States)

    Watanabe, Yoshiyuki; Tsukabe, Akio; Kunitomi, Yuki; Nishizawa, Mitsuo; Arisawa, Atsuko; Tanaka, Hisashi; Yoshiya, Kazuhisa; Shimazu, Takeshi; Tomiyama, Noriyuki

    2014-04-01

    Our study aimed to elucidate the diagnostic performance of dual-energy CT (DECT) in the detection of contrast enhancement in intracranial haematomas (ICrH) with early phase dual-energy computed tomography angiography (CTA) and compare the results with those obtained by delayed CT enhancement. Thirty-six patients with ICrH were retrospectively included in this study. All patients had undergone single-energy non-contrast CT and contrast-enhanced dual-source DECT. DECT images were post-processed with commercial software, followed by obtaining iodine images and virtual non-contrast images and generating combined images that created the impression of 120-kVp images. Two neuroradiologists, blinded to the patients' data, reviewed two reading sessions: session A (non-contrast CT and combined CT) and session B (non-contrast CT, combined CT, and iodine images) for detection of contrast enhancement in the haematomas. Contrast leakage or enhancement was detected in 23 (57.5 %) out of 40 haemorrhagic lesions in 36 patients on delayed CT. Three enhanced lesions were depicted only in the DECT iodine images. The sensitivity, specificity, positive predictive value, and negative predictive value of session A were 82.6, 94.1, 95.0, and 80.0 %, respectively, and those of session B were 95.7, 94.1, 95.7, and 94.1 %, respectively. DECT emphasised the iodine enhancement and facilitated the detection of contrast enhancement or leakage.

  14. Dual-energy CT for detection of contrast enhancement or leakage within high-density haematomas in patients with intracranial haemorrhage

    International Nuclear Information System (INIS)

    Watanabe, Yoshiyuki; Tsukabe, Akio; Kunitomi, Yuki; Nishizawa, Mitsuo; Arisawa, Atsuko; Tanaka, Hisashi; Tomiyama, Noriyuki; Yoshiya, Kazuhisa; Shimazu, Takeshi

    2014-01-01

    Our study aimed to elucidate the diagnostic performance of dual-energy CT (DECT) in the detection of contrast enhancement in intracranial haematomas (ICrH) with early phase dual-energy computed tomography angiography (CTA) and compare the results with those obtained by delayed CT enhancement. Thirty-six patients with ICrH were retrospectively included in this study. All patients had undergone single-energy non-contrast CT and contrast-enhanced dual-source DECT. DECT images were post-processed with commercial software, followed by obtaining iodine images and virtual non-contrast images and generating combined images that created the impression of 120-kVp images. Two neuroradiologists, blinded to the patients' data, reviewed two reading sessions: session A (non-contrast CT and combined CT) and session B (non-contrast CT, combined CT, and iodine images) for detection of contrast enhancement in the haematomas. Contrast leakage or enhancement was detected in 23 (57.5 %) out of 40 haemorrhagic lesions in 36 patients on delayed CT. Three enhanced lesions were depicted only in the DECT iodine images. The sensitivity, specificity, positive predictive value, and negative predictive value of session A were 82.6, 94.1, 95.0, and 80.0 %, respectively, and those of session B were 95.7, 94.1, 95.7, and 94.1 %, respectively. DECT emphasised the iodine enhancement and facilitated the detection of contrast enhancement or leakage. (orig.)

  15. Impact of Endoscopic Ultrasonography on (18)F-FDG-PET/CT Upfront Towards Patient Specific Esophageal Cancer Treatment

    NARCIS (Netherlands)

    Hulshoff, J. B.; Mul, V. E. M.; de Boer, H. E. M.; Noordzij, W.; Korteweg, T.; van Dullemen, H. M.; Nagengast, W. B.; Oppedijk, V.; Pierie, J. P. E. N.; Plukker, John Th. M.

    INTRODUCTION: In patients with potentially resectable esophageal cancer (EC), the value of endoscopic ultrasonography (EUS) after fluorine-18 labeled fluorodeoxyglucose positron emission tomography with computed tomography ((18)F-FDG-PET/CT) is questionable. Retrospectively, we assessed the impact

  16. TH-EF-BRA-04: Individually Optimized Contrast-Enhanced 4D-CT for Radiotherapy Simulation in Pancreatic Ductal Adenocarcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Choi, W; Xue, M; Lane, B; Patel, K; Regine, W; Wang, J; Chen, S; D’souza, W; Lu, W [University of Maryland School of Medicine, Baltimore, MD (United States); Kang, M [Kyungpook National University School of Medicine, Daegu (Korea, Republic of); Klahr, P [Philips Healthcare, Highland Heights, OH (United States)

    2016-06-15

    Purpose: To develop an individually optimized contrast-enhanced (CE) 4D-CT for radiotherapy simulation in pancreatic ductal adenocarcinomas (PDA). Methods: Ten PDA patients were enrolled. Each underwent 3 CT scans: a 4D-CT immediately following a CE 3D-CT and an individually optimized CE 4D-CT using test injection. Three physicians contoured the tumor and pancreatic tissues. We compared image quality scores, tumor volume, motion, tumor-to-pancreas contrast, and contrast-to-noise ratio (CNR) in the 3 CTs. We also evaluated interobserver variations in contouring the tumor using simultaneous truth and performance level estimation (STAPLE). Results: Average image quality scores for CE 3DCT and CE 4D-CT were comparable (4.0 and 3.8, respectively; P=0.47), and both were significantly better than that for 4D-CT (2.6, P<0.001). Tumor-to-pancreas contrast results were comparable in CE 3D-CT and CE 4D-CT (15.5 and 16.7 HU, respectively; P=0.71), and the latter was significantly higher than in 4D-CT (9.2 HU, P=0.03). Image noise in CE 3D-CT (12.5 HU) was significantly lower than in CE 4D-CT (22.1 HU, P<0.001) and 4D-CT (19.4 HU, P=0.005). CNRs were comparable in CE 3D-CT and CE 4DCT (1.4 and 0.8, respectively; P=0.23), and the former was significantly better than in 4D-CT (0.6, P = 0.04). Mean tumor volumes were smaller in CE 3D-CT (29.8 cm{sup 3}) and CE 4D-CT (22.8 cm{sup 3}) than in 4D-CT (42.0 cm{sup 3}), although these differences were not statistically significant. Mean tumor motion was comparable in 4D-CT and CE 4D-CT (7.2 and 6.2 mm, P=0.23). Interobserver variations were comparable in CE 3D-CT and CE 4D-CT (Jaccard index 66.0% and 61.9%, respectively) and were worse for 4D-CT (55.6%) than CE 3D-CT. Conclusion: CE 4D-CT demonstrated characteristics comparable to CE 3D-CT, with high potential for simultaneously delineating the tumor and quantifying tumor motion with a single scan. Supported in part by Philips Healthcare.

  17. Differentiation of focal-type autoimmune pancreatitis from pancreatic carcinoma: assessment by multiphase contrast-enhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    Furuhashi, Naohiro; Suzuki, Kojiro; Sakurai, Yusuke; Naganawa, Shinji [Nagoya University Graduate School of Medicine, Department of Radiology, Nagoya (Japan); Ikeda, Mitsuru [Nagoya University Graduate School of Medicine, Department of Radiological Technology, Nagoya (Japan); Kawai, Yuichi [Japanese Red Cross Nagoya Daiichi Hospital, Department of Diagnostic Radiology, Nagoya (Japan)

    2015-05-01

    To evaluate the utility of multiphase contrast-enhanced computed tomography (CT) findings alone and in combination for differentiating focal-type autoimmune pancreatitis (f-AIP) from pancreatic carcinoma (PC). The study group comprised 22 f-AIP lesions and 61 PC lesions. Two radiologists independently evaluated CT findings. Frequencies of findings were compared between f-AIP and PC. Statistical, univariate and multivariate analyses were performed. Homogeneous enhancement during the portal phase (AIP, 59 % vs. PC, 3 %; P < 0.001), dotted enhancement during the pancreatic phase (50 % vs. 7 %; P < 0.001), duct-penetrating sign (46 % vs. 2 %; P < 0.001), enhanced duct sign (36 % vs. 2 %; P < 0.001) and capsule-like rim (46 % vs. 3 %; P < 0.001) were more frequently observed in AIP. Ring-like enhancement during the delayed phase (5 % vs. 46 %; P < 0.001) and peripancreatic strands with a length of at least 10 mm (5 % vs. 39 %; P = 0.001) were more frequently observed in PC. AIP was identified with 82 % sensitivity and 98 % specificity using four of these seven findings. Multivariate analysis revealed significant differences in dotted enhancement (P = 0.004), duct-penetrating sign (P < 0.001) and capsule-like rim (P = 0.007). The combination of CT findings may allow improvements in differentiating f-AIP from PC. (orig.)

  18. Tracer kinetic modelling of tumour angiogenesis based on dynamic contrast-enhanced CT and MRI measurements

    Energy Technology Data Exchange (ETDEWEB)

    Brix, Gunnar [Federal Office for Radiation Protection, Department of Medical and Occupational Radiation Protection, Oberschleissheim (Germany); Bundesamt fuer Strahlenschutz (BfS), Abteilung fuer medizinischen und beruflichen Strahlenschutz, Oberschleissheim (Germany); Griebel, Juergen [Federal Office for Radiation Protection, Department of Medical and Occupational Radiation Protection, Oberschleissheim (Germany); Kiessling, Fabian [RWTH-Aachen University, Department of Experimental Molecular Imaging, Aachen (Germany); Wenz, Frederik [University Medical Center Mannheim, University of Heidelberg, Department of Radiation Oncology, Mannheim (Germany)

    2010-08-15

    Technical developments in both magnetic resonance imaging (MRI) and computed tomography (CT) have helped to reduce scan times and expedited the development of dynamic contrast-enhanced (DCE) imaging techniques. Since the temporal change of the image signal following the administration of a diffusible, extracellular contrast agent (CA) is related to the local blood supply and the extravasation of the CA into the interstitial space, DCE imaging can be used to assess tissue microvasculature and microcirculation. It is the aim of this review to summarize the biophysical and tracer kinetic principles underlying this emerging imaging technique offering great potential for non-invasive characterization of tumour angiogenesis. In the first part, the relevant contrast mechanisms are presented that form the basis to relate signal variations measured by serial CT and MRI to local tissue concentrations of the administered CA. In the second part, the concepts most widely used for tracer kinetic modelling of concentration-time courses derived from measured DCE image data sets are described in a consistent and unified manner to highlight their particular structure and assumptions as well as the relationships among them. Finally, the concepts presented are exemplified by the analysis of representative DCE data as well as discussed with respect to present and future applications in cancer diagnosis and therapy. Depending on the specific protocol used for the acquisition of DCE image data and the particular model applied for tracer kinetic analysis of the derived concentration-time courses, different aspects of tumour angiogenesis can be quantified in terms of well-defined physiological tissue parameters. DCE imaging offers promising prospects for improved tumour diagnosis, individualization of cancer treatment as well as the evaluation of novel therapeutic concepts in preclinical and early-stage clinical trials. (orig.)

  19. Estimation of absorbed dose of radiosensitive organs and effective sose in patients underwent abdominopelvic spiral CT scan using impact CT patient dosimetry

    Directory of Open Access Journals (Sweden)

    Ayoub Amirnia

    2017-05-01

    Full Text Available Background: Due to the presence of radiosensitive organs in the abdominopelvic region and increasing the number of requests for CT scan examinations, concerns about increasing radiation doses in patients has been greatly elevated. Therefore, the goal of this study was to determine the absorbed dose of radiosensitive organs and the effective dose in patients underwent abdominopelvic CT scan using ImPACT CT patient dosimetry Calculator (version 1.0.4, Imaging Performance Assessment on Computed Tomography, www.impactscan.org. Methods: This prospective cross-sectional study was conducted in Imam Reza Hospital from November to February 2015 February 2015 in the Imam Reza Hospital, in Urmia, Iran. The demographic and dosimetric information of 100 patients who underwent abdominopelvic CT scan in a 6-slice CT scanner were obtained through the data collection forms. The demographic data of the patients included age, weight, gender, and BMI. The dosimetric parameters included pitch value, CT dose volume index (CTDIvol, dose-length product (DLP, tube voltage, tube current, exposure time, collimation size, scan length, and scan time. To determine the absorbed dose of radiosensitive organs and also the effective dose in patients, ImPACT CT patient dosimetry calculator was used. Results: The results of this study demonstrated that the mean and standard deviation (SD of patients' effective dose in abdominopelvic CT scan was 4.927±0.164 mSv. The bladder in both genders had the greatest mean organ dose, which was 64.71±17.15 mGy for men and 77.56±18.48 mGy for women (P<0.001. Conclusion: The effective dose values of this examination are in the same range as previous studies, as well as International Commission on Radiological Protection (ICRP recommendations. However, the radiation dose from CT scan has the largest contribution to the medical imaging. According to the ALARA principle, it is recommended that the scan parameters, especially mAs, should be

  20. CT findings of intraductal papillary neoplasm of the bile duct: Assessment with multiphase contrast-enhanced examination using multi-detector CT

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, H., E-mail: ogawa.hiroshi@h.mbox.nagoya-u.ac.jp [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Itoh, S. [Department of Radiology, Japanese Red Cross Nagoya Daiichi Hospital, Nagoya (Japan); Nagasaka, T. [Department of Medical Technology, Nagoya University School of Health Sciences, Nagoya (Japan); Suzuki, K. [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Ota, T. [Department of Radiology, Aichi Medical University Hospital, Nagakute Aichi (Japan); Naganawa, S. [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan)

    2012-03-15

    Aim: To evaluate multi-detector computed tomography (MDCT) findings of intraductal papillary neoplasm of the bile duct (IPNB), a neoplasm that is considered to be the biliary counterpart of pancreatic intraductal papillary mucinous neoplasm. Materials and methods: Two radiologists retrospectively evaluated multiphase contrast-enhanced CT images with 0.5 or 1 mm collimation in 37 consecutive patients with resected IPNB diagnosed by a single pathologist. The CT findings were correlated with the pathological findings concerning invasion of the surrounding organs and vessels. Results: All patients showed bile duct dilatation. An intraductal mass was detected in 36 patients and the following findings were observed: extensive infiltration along the bile duct more than 20 mm (n = 32), compared with normal hepatic parenchyma, isodense or hyperdense during the late arterial phase (n = 31), not hyperdense during the portal-venous and delayed phases (n = 36), and intense enhancement rim at the base of the mass during the portal-venous or delayed phase (n = 27). Parenchymal invasion of the surrounding organs was seen in eight of 16 tumours showing irregular or bulging margins. Vascular invasion was false positive in four of eight tumours. Conclusions: IPNB exhibits relatively characteristic findings with multiphase contrast-enhanced examination using MDCT. A tendency to overestimate invasion of the surrounding organs and vessels was seen.

  1. Optimized enhancement in helical CT: Experiences with a real-time bolus tracking system in 628 patients

    International Nuclear Information System (INIS)

    Kirchner, J.; Kickuth, R.; Laufer, U.; Noack, M.; Liermann, D.

    2000-01-01

    AIMS: Ultrafast detector technology enables bolus-triggered application of contrast media. In a prospective study we investigated the benefit of this new method with the intention of optimizing enhancement during examination of the chest and abdomen. MATERIALS AND METHODS: In total, we examined 548 patients under standardized conditions. All examinations were performed on a Somatom Plus 4 Power CT system (Siemens Corp., Forchheim, Germany) using the CARE-Bolus software. This produces repetitive low-dose test images (e.g. for the lung: 140 kV, 43 mA, TI 0.5 s) and measures the Hounsfield attenuation in a pre-selected region of interest. After exceeding a defined threshold, a diagnostic spiral CT examination was begun automatically. The data obtained from 321 abdominal CT and 179 lung CT examinations were correlated with different parameters such as age, weight and height of the patients and parameters of vascular access. In a group of 80 patients, the injection of contrast medium was stopped after reaching a pre-defined threshold of an increase of 100 HU over the baseline. Then, we assessed the maximal enhancement of liver, pulmonal artery trunk and aortic arch. RESULTS: There was no correlation between bolus geometry and age, body surface or weight. In helical CT of the abdomen the threshold was reached after a mean trigger time of 27 s (range 13-67 s) and only 65 ml (range 41-105 ml) of contrast medium were administered. In helical CT of the lung the threshold was reached after 21 s (range 12-48 s) and the mean amount of administered contrast medium was 48 ml (range 38-71 ml). CONCLUSION: Bolus triggering allows optimized enhancement of the organs and reduces the dose of contrast material required compared with standard administration. Kirchner, J. (2000). Clinical Radiology 55, 368-373

  2. Optimized enhancement in helical CT: experiences with a real-time bolus tracking system in 628 patients.

    Science.gov (United States)

    Kirchner, J; Kickuth, R; Laufer, U; Noack, M; Liermann, D

    2000-05-01

    Ultrafast detector technology enables bolus-triggered application of contrast media. In a prospective study we investigated the benefit of this new method with the intention of optimizing enhancement during examination of the chest and abdomen. In total, we examined 548 patients under standardized conditions. All examinations were performed on a Somatom Plus 4 Power CT system (Siemens Corp., Forchheim, Germany) using the CARE-Bolus software. This produces repetitive low-dose test images (e.g. for the lung: 140 kV, 43 mA, TI 0.5 s) and measures the Hounsfield attenuation in a pre-selected region of interest. After exceeding a defined threshold, a diagnostic spiral CT examination was begun automatically. The data obtained from 321 abdominal CT and 179 lung CT examinations were correlated with different parameters such as age, weight and height of the patients and parameters of vascular access. In a group of 80 patients, the injection of contrast medium was stopped after reaching a pre-defined threshold of an increase of 100 HU over the baseline. Then, we assessed the maximal enhancement of liver, pulmonal artery trunk and aortic arch. There was no correlation between bolus geometry and age, body surface or weight. In helical CT of the abdomen the threshold was reached after a mean trigger time of 27 s (range 13-67 s) and only 65 ml (range 41-105 ml) of contrast medium were administered. In helical CT of the lung the threshold was reached after 21 s (range 12-48 s) and the mean amount of administered contrast medium was 48 ml (range 38-71 ml). Bolus triggering allows optimized enhancement of the organs and reduces the dose of contrast material required compared with standard administration. Copyright 2000 The Royal College of Radiologists.

  3. Dynamic contrast-enhanced perfusion area-detector CT assessed with various mathematical models: Its capability for therapeutic outcome prediction for non-small cell lung cancer patients with chemoradiotherapy as compared with that of FDG-PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.jp [Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe (Japan); Fujisawa, Yasuko [Toshiba Medical Systems Corporation, Otawara (Japan); Koyama, Hisanobu; Kishida, Yuji; Seki, Shinichiro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Sugihara, Naoki [Toshiba Medical Systems Corporation, Otawara (Japan); Yoshikawa, Takeshi [Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe (Japan)

    2017-01-15

    Purpose: To directly compare the capability of dynamic first-pass contrast-enhanced (CE-) perfusion area-detector CT (ADCT) and PET/CT for early prediction of treatment response, disease progression and overall survival of non-small cell carcinoma (NSCLC) patients treated with chemoradiotherapy. Materials and methods: Fifty-three consecutive Stage IIIB NSCLC patients who had undergone PET/CT, dynamic first-pass CE-perfusion ADCT, chemoradiotherapy, and follow-up examination were enrolled in this study. They were divided into two groups: 1) complete or partial response (CR + PR) and 2) stable or progressive disease (SD + PD). Pulmonary arterial and systemic arterial perfusions and total perfusion were assessed at targeted lesions with the dual-input maximum slope method, permeability surface and distribution volume with the Patlak plot method, tumor perfusion with the single-input maximum slope method, and SUV{sub max}, and results were averaged to determine final values for each patient. Next, step-wise regression analysis was used to determine which indices were the most useful for predicting therapeutic effect. Finally, overall survival of responders and non-responders assessed by using the indices that had a significant effect on prediction of therapeutic outcome was statistically compared. Results: The step-wise regression test showed that therapeutic effect (r{sup 2} = 0.63, p = 0.01) was significantly affected by the following three factors in order of magnitude of impact: systemic arterial perfusion, total perfusion, and SUV{sub max}. Mean overall survival showed a significant difference for total perfusion (p = 0.003) and systemic arterial perfusion (p = 0.04). Conclusion: Dynamic first-pass CE-perfusion ADCT as well as PET/CT are useful for treatment response prediction in NSCLC patients treated with chemoradiotherapy.

  4. Dynamic contrast-enhanced perfusion area-detector CT assessed with various mathematical models: Its capability for therapeutic outcome prediction for non-small cell lung cancer patients with chemoradiotherapy as compared with that of FDG-PET/CT

    International Nuclear Information System (INIS)

    Ohno, Yoshiharu; Fujisawa, Yasuko; Koyama, Hisanobu; Kishida, Yuji; Seki, Shinichiro; Sugihara, Naoki; Yoshikawa, Takeshi

    2017-01-01

    Purpose: To directly compare the capability of dynamic first-pass contrast-enhanced (CE-) perfusion area-detector CT (ADCT) and PET/CT for early prediction of treatment response, disease progression and overall survival of non-small cell carcinoma (NSCLC) patients treated with chemoradiotherapy. Materials and methods: Fifty-three consecutive Stage IIIB NSCLC patients who had undergone PET/CT, dynamic first-pass CE-perfusion ADCT, chemoradiotherapy, and follow-up examination were enrolled in this study. They were divided into two groups: 1) complete or partial response (CR + PR) and 2) stable or progressive disease (SD + PD). Pulmonary arterial and systemic arterial perfusions and total perfusion were assessed at targeted lesions with the dual-input maximum slope method, permeability surface and distribution volume with the Patlak plot method, tumor perfusion with the single-input maximum slope method, and SUV max , and results were averaged to determine final values for each patient. Next, step-wise regression analysis was used to determine which indices were the most useful for predicting therapeutic effect. Finally, overall survival of responders and non-responders assessed by using the indices that had a significant effect on prediction of therapeutic outcome was statistically compared. Results: The step-wise regression test showed that therapeutic effect (r 2 = 0.63, p = 0.01) was significantly affected by the following three factors in order of magnitude of impact: systemic arterial perfusion, total perfusion, and SUV max . Mean overall survival showed a significant difference for total perfusion (p = 0.003) and systemic arterial perfusion (p = 0.04). Conclusion: Dynamic first-pass CE-perfusion ADCT as well as PET/CT are useful for treatment response prediction in NSCLC patients treated with chemoradiotherapy.

  5. Dynamic contrast-enhanced perfusion area-detector CT assessed with various mathematical models: Its capability for therapeutic outcome prediction for non-small cell lung cancer patients with chemoradiotherapy as compared with that of FDG-PET/CT.

    Science.gov (United States)

    Ohno, Yoshiharu; Fujisawa, Yasuko; Koyama, Hisanobu; Kishida, Yuji; Seki, Shinichiro; Sugihara, Naoki; Yoshikawa, Takeshi

    2017-01-01

    To directly compare the capability of dynamic first-pass contrast-enhanced (CE-) perfusion area-detector CT (ADCT) and PET/CT for early prediction of treatment response, disease progression and overall survival of non-small cell carcinoma (NSCLC) patients treated with chemoradiotherapy. Fifty-three consecutive Stage IIIB NSCLC patients who had undergone PET/CT, dynamic first-pass CE-perfusion ADCT, chemoradiotherapy, and follow-up examination were enrolled in this study. They were divided into two groups: 1) complete or partial response (CR+PR) and 2) stable or progressive disease (SD+PD). Pulmonary arterial and systemic arterial perfusions and total perfusion were assessed at targeted lesions with the dual-input maximum slope method, permeability surface and distribution volume with the Patlak plot method, tumor perfusion with the single-input maximum slope method, and SUV max , and results were averaged to determine final values for each patient. Next, step-wise regression analysis was used to determine which indices were the most useful for predicting therapeutic effect. Finally, overall survival of responders and non-responders assessed by using the indices that had a significant effect on prediction of therapeutic outcome was statistically compared. The step-wise regression test showed that therapeutic effect (r 2 =0.63, p=0.01) was significantly affected by the following three factors in order of magnitude of impact: systemic arterial perfusion, total perfusion, and SUV max . Mean overall survival showed a significant difference for total perfusion (p=0.003) and systemic arterial perfusion (p=0.04). Dynamic first-pass CE-perfusion ADCT as well as PET/CT are useful for treatment response prediction in NSCLC patients treated with chemoradiotherapy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Segmentation of urinary bladder in CT urography (CTU) using CLASS with enhanced contour conjoint procedure

    Science.gov (United States)

    Cha, Kenny; Hadjiiski, Lubomir; Chan, Heang-Ping; Cohan, Richard H.; Caoili, Elaine M.; Zhou, Chuan

    2014-03-01

    We are developing a computerized method for bladder segmentation in CT urography (CTU) for computeraided diagnosis of bladder cancer. A challenge for computerized bladder segmentation in CTU is that the bladder often contains regions filled with intravenous (IV) contrast and without contrast. Previously, we proposed a Conjoint Level set Analysis and Segmentation System (CLASS) consisting of four stages: preprocessing and initial segmentation, 3D and 2D level set segmentation, and post-processing. In case the bladder is partially filled with contrast, CLASS segments the non-contrast (NC) region and the contrast (C) filled region separately and conjoins the contours with a Contour Conjoint Procedure (CCP). The CCP is not trivial. Inaccuracies in the NC and C contours may cause CCP to exclude portions of the bladder. To alleviate this problem, we implemented model-guided refinement to propagate the C contour if the level set propagation in the region stops prematurely due to substantial non-uniformity of the contrast. An enhanced CCP with regularized energies further propagates the conjoint contours to the correct bladder boundary. Segmentation performance was evaluated using 70 cases. For all cases, 3D hand segmented contours were obtained as reference standard, and computerized segmentation accuracy was evaluated in terms of average volume intersection %, average % volume error, and average minimum distance. With enhanced CCP, those values were 84.4±10.6%, 8.3±16.1%, 3.4±1.8 mm, respectively. With CLASS, those values were 74.6±13.1%, 19.6±18.6%, 4.4±2.2 mm, respectively. The enhanced CCP improved bladder segmentation significantly (p<0.001) for all three performance measures.

  7. Comparison of neuroendocrine tumor detection and characterization using DOTATOC-PET in correlation with contrast enhanced CT and delayed contrast enhanced MRI

    International Nuclear Information System (INIS)

    Giesel, F.L.; Kratochwil, C.; Mehndiratta, A.; Wulfert, S.; Moltz, J.H.; Zechmann, C.M.; Kauczor, H.U.; Haberkorn, U.; Ley, S.

    2012-01-01

    Purpose: We evaluated the rate of successful characterization of gastroenteropancreatic neuroendocrine tumors (NETs) present with an increased somatostatin receptor, comparing CE-CT with CE-MRI, each in correlation with DOTATOC-PET. Methods and materials: 8 patients with GEP-NET were imaged using CE-MRI (Gd-EOB-DTPA), CE-CT (Imeron 400) and DOTATOC-PET. Contrast-enhancement of normal liver-tissue and metastasis was quantified with ROI-technique. Tumor delineation was assessed with visual-score in blind-read-analysis by two experienced radiologists. Results: Out of 40 liver metastases in patients with NETs, all were detected by CE-MRI and the lesion extent could be adequately assessed, whereas CT failed to detect 20% of all metastases. The blind-read-score of CT in arterial and portal phase was median −0.65 and −1.4, respectively, and 2.7 for delayed-MRI. The quantitative ROI-analysis presented an improved contrast-enhancement-ratio with a median of 1.2, 1.6 and 3.3 for CE-CT arterial, portal-phase and delayed-MRI respectively. Conclusion: Late CE-MRI was superior to CE-CT in providing additionally morphologic characterization and exact lesion extension of hepatic metastases from neuroendocrine tumor detected with DOTATOC-PET. Therefore, late enhanced Gd-EOB-DTPA-MRI seems to be the adequate imaging modality for combination with DOTATOC-PET to provide complementary (macroscopic and molecular) tumor characterization in hepatic metastasized NETs

  8. Ring-enhancement pattern on contrast-enhanced CT predicts adenosquamous carcinoma of the pancreas: a matched case-control study.

    Science.gov (United States)

    Imaoka, Hiroshi; Shimizu, Yasuhiro; Mizuno, Nobumasa; Hara, Kazuo; Hijioka, Susumu; Tajika, Masahiro; Tanaka, Tsutomu; Ishihara, Makoto; Ogura, Takeshi; Obayashi, Tomohiko; Shinagawa, Akihide; Sakaguchi, Masafumi; Yamaura, Hidekazu; Kato, Mina; Niwa, Yasumasa; Yamao, Kenji

    2014-01-01

    Adenosquamous carcinoma of the pancreas (ASC) is a rare malignant neoplasm of the pancreas, exhibiting both glandular and squamous differentiation. However, little is known about its imaging features. This study examined the imaging features of pancreatic ASC. We evaluated images of contrast-enhanced computed tomography (CT) and endoscopic ultrasonography (EUS). As controls, solid pancreatic neoplasms matched in a 2:1 ratio to ASC cases for age, sex and tumor location were also evaluated. Twenty-three ASC cases were examined, and 46 solid pancreatic neoplasms (43 pancreatic ductal adenocarcinomas, two pancreatic neuroendocrine tumors and one acinar cell carcinoma) were matched as controls. Univariate analysis demonstrated significant differences in the outline and vascularity of tumors on contrast-enhanced CT in the ASC and control groups (P outline, cystic changes, and the ring-enhancement pattern on contrast-enhanced CT were seen to have significant predictive powers by stepwise forward logistic regression analysis (P = 0.044, P = 0.010, and P = 0.001, respectively). Of the three, the ring-enhancement pattern was the most useful, and its predictive diagnostic sensitivity, specificity, positive predictive value and negative predictive value for diagnosis of ASC were 65.2%, 89.6%, 75.0% and 84.3%, respectively. These results demonstrate that presence of the ring-enhancement pattern on contrast-enhanced CT is the most useful predictive factor for ASC. Copyright © 2014 IAP and EPC. Published by Elsevier B.V. All rights reserved.

  9. Liver Imaging Reporting and Data System on CT and gadoxetic acid-enhanced MRI with diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Dong Ik; Jang, Kyung Mi; Kim, Seong Hyun; Kang, Tae Wook; Song, Kyoung Doo [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of)

    2017-10-15

    To assess major imaging features of Liver Imaging Reporting and Data System (LI-RADS) on contrast-enhanced CT and gadoxetic acid-enhanced MRI and to estimate whether the combination of signal intensity favouring HCC on hepatobiliary phase (HBP) and diffusion-weighted images (DWI) can act as a major feature in LI-RADS. Four hundred twenty one patients with 445 observations were included. Major features of LI-RADS on CT and MRI as well as HBP and DWI features were assessed. Diagnostic performances of LR-5 according to LI-RADS v2014 and modified LI-RADS which incorporate combination of HBP and DWI were assessed. Pairwise comparisons of the receiver operating characteristic (ROC) curves were performed. For HCCs, capsule appearance had the highest rate of discordance between CT and MRI (32.7%), followed by washout appearance (22.2%). Specificity (75%) of LR-5 of LI-RADS v2014 was lower than that (77.1-79.2%) of modified LI-RADS. Area under the ROC curve of modified LI-RADS (0.755-0.775) was not significantly different from that of LI-RADS v 2014 (0.709) (p > 0.05). There were substantial discordances between CT and MRI for capsule and washout appearances in hepatic observations, and combination of gadoxetic acid-enhanced MRI and DWI might be able to be incorporated as a major feature of LI-RADS. (orig.)

  10. Contrast-enhanced CT in determining resectability in patients with pancreatic carcinoma: a meta-analysis of the positive predictive values of CT

    Energy Technology Data Exchange (ETDEWEB)

    Somers, Inne; Bipat, Shandra [University of Amsterdam, Department of Radiology, Academic Medical Centre, Amsterdam (Netherlands)

    2017-08-15

    To obtain a summary positive predictive value (sPPV) of contrast-enhanced CT in determining resectability. The MEDLINE and EMBASE databases from JAN2005 to DEC2015 were searched and checked for inclusion criteria. Data on study design, patient characteristics, imaging techniques, image evaluation, reference standard, time interval between CT and reference standard, and data on resectability/unresectablity were extracted by two reviewers. We used a fixed-effects or random-effects approach to obtain sPPV for resectability. Several subgroups were defined: 1) bolus-triggering versus fixed-timing; 2) pancreatic and portal phases versus portal phase alone; 3) all criteria (liver metastases/lymphnode involvement/local advanced/vascular invasion) versus only vascular invasion as criteria for unresectability. Twenty-nine articles were included (2171 patients). Most studies were performed in multicentre settings, initiated by the department of radiology and retrospectively performed. The I{sup 2}-value was 68%, indicating heterogeneity of data. The sPPV was 81% (95%CI: 75-86%). False positives were mostly liver, peritoneal, or lymphnode metastases. Bolus-triggering had a slightly higher sPPV compared to fixed-timing, 87% (95%CI: 81-91%) versus 78% (95%CI: 66-86%) (p = 0.077). No differences were observed in other subgroups. This meta-analysis showed a sPPV of 81% for predicting resectability by CT, meaning that 19% of patients falsely undergo surgical exploration. (orig.)

  11. Impact of imaging quality of change pitch on coronary CTA with 64-detector row CT

    International Nuclear Information System (INIS)

    Li Xiang; Jin Chaolin; Zhang Shutong

    2009-01-01

    Objective: To investigate the impact of imaging quality of pitch on coronary CT angiography (CTA) with 64-detector row CT. Methods: 566 patients were divided into four groups according to heart rate (≤ 50, 51 ∼ 70, 71 ∼ 80 and ≥ 80 bpm). Three dimensional reconstructions were used such as volume rendering (VR), maximum intensity projection(MIP) and curved planar reformation (CPR). Each group was divided into control group and experimential group randomly, using normal pitch and revised pitch respectively, and the imaging quality and influencing factors were analyzed among the four groups. Results: There was significant difference in imaging quality among the four groups (P < 0.05). Each group had difference in imaging quality with normal pitch and revised pitch. Conclusions: The revised pitch helps to improve the imaging quality and meet the demand of diagnosis. (authors)

  12. The Effect of the Degree of Luminal Contrast-Enhancement on CT Measurement of Plaque Size: A Comparison with T1-weighted Magnetic Resonance Imaging

    International Nuclear Information System (INIS)

    Choi, Byoung Wook; Hur, Jin; Lee, Hye Jeong; Kim, Young Jin; Choe, Kyu Ok; Kim, Tae Hoon

    2010-01-01

    We studied early and delayed contrast-enhanced CT to determine the effects of the degree of luminal enhancement on the measurement of plaque size compared to T1-weighted MRI. T1-weighted MRI and a two-phase contrast-enhanced CT was performed in 5 New Zealand white rabbits with atherosclerosis. Early-phase images were acquired during an expected peak enhancement period of the lumen; delayed-phase images were acquired 240 sec after administration of the contrast media. Anteroposterior and lateral luminal diameters (APD, LD), luminal area (LA), total vessel area (TVA), and plaque area (PA) of the aorta were measured on MRI and CT, respectively and compared to each other. A total of 78 slices of the aorta were analyzed. PA, measured on T1-weighted MR images, was significantly greater than PA for both early-phase and delayed-phase CT (p 2 (p 2 (p 2 (p = 0.159) for MRI vs. early-phase CT, MRI vs. delayed-phase CT, and early-phase CT vs. delayed-phase CT, respectively. Different luminal densities by contrast enhancement do not affect the CT measurement of plaque area for the detection of obstructive coronary artery disease

  13. Evaluation of dynamic enhanced CT scanning in the differentiation of adrenal lipid-poor adenomas with metastases

    International Nuclear Information System (INIS)

    Fang Xiangming; Hu Chunhong; Hu Xiaoyun; Chen Hongwei; Wu Liyuan; Zou Xinnong; Qian Pingyan

    2006-01-01

    Objective: To evaluate dynamic enhanced CT in differentiating adrenal metastases from adrenal lipid-poor adenomas(ALPA). Methods: Both plain and dynamic enhanced CT scanning was performed in 9 metastases with 13 masses and 28 lipid-poor adenoma with 30 masses. The types of time-density curve according to peak time(PT) and relative washout percentage(Washr) besides shape, size, margin, internal structure, surrounding status and enhanced pattern of each lesion were measuerd and compared between the two groups of metastases and ALPA. Results: There is difference between metastases and ALPA in the aspects of shape, density, neighboring structure and the type of enhancement. The type of TDC of matastases was characterized by fast-washin and fast-washout, which was quite differed from the type of TDC of ALPA characterized by fast-washin and slow-washout. According to this, the sensitiveity and specificity for differentiating metastases from ALPA were 96.7%, 92.3%. Conclusion: The types of TDC of dynamic enhanced CT is of great value in differentiating metastases from ALPA. (authors)

  14. Has F.D.G. PET/CT an impact on the management of patients with anal carcinoma?

    International Nuclear Information System (INIS)

    Vercellino, L.; Nataf, V.; Kerrou, K.; Huchet, V.; Pascal, O.; Montravers, F.; Talbot, J.N.; De Parades, V.; Bauer, P.; Touboul, E.

    2010-01-01

    Purpose: To evaluate the impact of F.D.G. PET/C Ton the management of patients referred for the staging and/or the follow-up of anal carcinoma, and PET/CT on patient management. Patients and methods: We included patients referred to our department for anal carcinoma whose therapeutic management was evaluable thanks to follow-up data during at least 6 months. Results: Data of 44 patients were analysed: 22 had PET/CT for initial staging and 36 during follow-up. PET/CT had impact in nine patients out of 44 (20%) and it was relevant in eight of them. Conclusion: F.D.G. PET/CT is an accurate imaging modality in anal cancer, its impact on patient management is more obvious when persistence or recurrence of disease is suspected. (authors)

  15. FDG PET/CT in pediatric primary bone tumours: comparison with conventional imaging (CI) and management impact assesment

    International Nuclear Information System (INIS)

    Stege, Claudia; London, Kevin; Cross, Siobhan; Howman-Giles, Robert; Onikul, Ella; Graf, Nicole; Pozza, L.D.

    2009-01-01

    Full text: To evaluate PET/CT in pediatric primary bone tumours (PBT), the accuracy, clinical impact, prognostic indicators in predicting tumour response to therapy and determining epiphyseal involvement were compared to Cl. Methods: A retrospective review of PET/CT scans with CI was performed. Lesions were compared to a reference standard: histopathology or follow up >6 mths. Pt based analysis was performed for clinical impact. Prognostic indicators (SUYmax, tumour size) were compared to histopathology response post chemotherapy. Results: 43 pts (average 12.9 yrs) with osteosarcoma (I 8), Ewing's sarcoma (21), PNE (4) were analysed. 109 PET/CT scans with CI scans were evaluated (371 lesions). 33 lesions were discordant. Accuracy of PET/CT was higher for all lesions than CI (95% vs92%) but sensitivity was lower (79% vs 83%). Excluding lung lesions, sensitivities increased for PET/CT and CI (92% vs 89%). 9pts had PET/CT staging and follow up with histopathological evaluation post chemotherapy: 2pts poor responders, 7 good responders. Good responders had a higher SUYmax at diagnosis compared to poor responders (av 13.84 vs 7.95) but reduced more [10.5(70%) vs 3.5( 45%)]following chemotherapy. There were no false negatives for epiphyseal involvement for PET/CT and CI but one PET/CT was false positive. Conclusion: PET/CT is less sensitive in small lung lesions, but more sensitive in other areas compared to Cl. SUYmax at diagnosis is a poor predictor of response, but percent decrease post therapy was associated with therapeutic response. Change in tumour size on MR is a poor predictor of response. There is improved clinical impact with PET/CT in patient management.

  16. Oxygen-enhanced MRI for patients with connective tissue diseases: Comparison with thin-section CT of capability for pulmonary functional and disease severity assessment

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.jp [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Nishio, Mizuho [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Koyama, Hisanobu [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Yoshikawa, Takeshi; Matsumoto, Sumiaki [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Seki, Shinichiro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Tsubakimoto, Maho [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nakagami-Gun, Okinawa (Japan); Sugimura, Kazuro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan)

    2014-02-15

    Purpose: To prospectively and directly compare oxygen-enhanced (O{sub 2}-enhanced) MRI with thin-section CT for pulmonary functional loss and disease severity assessment in connective tissue disease (CTD) patients with interstitial lung disease (ILD). Materials and methods: Thin-section CT, O{sub 2}-enhanced MRI, pulmonary function test and serum KL-6 were administered to 36 CTD patients with ILD (23 men, 13 women; mean age: 63.9 years) and nine CTD patients without ILD (six men, and three women; mean age: 62.0 years). A relative-enhancement ratio (RER) map was generated from O{sub 2}-enhanced MRI and mean relative enhancement ratio (MRER) for each subject was calculated from all ROI measurements. CT-assessed disease severity was evaluated with a visual scoring system from each of the thin-section CT data. MRER and CT-assessed disease severities of CTD patients with and without ILD were then statistically compared. To assess capability for pulmonary functional loss and disease severity assessment in CTD patients, correlations of MRER and CT-assessed disease severity with pulmonary functional parameters and serum KL-6 in all subjects were statistically determined. Results: MRER and CT-assessed disease severity showed significant differences between CTD patients with (MRER: 0.15 ± 0.08, CT-assessed disease severity: 13.0 ± 7.4%) and without ILD (MRER: 0.25 ± 0.06, p = 0.0011; CT-assessed disease severity: 1.6 ± 1.6%, p < 0.0001). MRER and CT-assessed disease severity correlated significantly with pulmonary functional parameters and serum KL-6 in all subjects (0.61 ≤ r ≤ 0.79, p < 0.05). Conclusion: O{sub 2}-enhanced MRI was found to be as useful as thin-section CT for pulmonary functional loss and disease severity assessment of CTD patients with ILD.

  17. Oxygen-enhanced MRI for patients with connective tissue diseases: Comparison with thin-section CT of capability for pulmonary functional and disease severity assessment

    International Nuclear Information System (INIS)

    Ohno, Yoshiharu; Nishio, Mizuho; Koyama, Hisanobu; Yoshikawa, Takeshi; Matsumoto, Sumiaki; Seki, Shinichiro; Tsubakimoto, Maho; Sugimura, Kazuro

    2014-01-01

    Purpose: To prospectively and directly compare oxygen-enhanced (O 2 -enhanced) MRI with thin-section CT for pulmonary functional loss and disease severity assessment in connective tissue disease (CTD) patients with interstitial lung disease (ILD). Materials and methods: Thin-section CT, O 2 -enhanced MRI, pulmonary function test and serum KL-6 were administered to 36 CTD patients with ILD (23 men, 13 women; mean age: 63.9 years) and nine CTD patients without ILD (six men, and three women; mean age: 62.0 years). A relative-enhancement ratio (RER) map was generated from O 2 -enhanced MRI and mean relative enhancement ratio (MRER) for each subject was calculated from all ROI measurements. CT-assessed disease severity was evaluated with a visual scoring system from each of the thin-section CT data. MRER and CT-assessed disease severities of CTD patients with and without ILD were then statistically compared. To assess capability for pulmonary functional loss and disease severity assessment in CTD patients, correlations of MRER and CT-assessed disease severity with pulmonary functional parameters and serum KL-6 in all subjects were statistically determined. Results: MRER and CT-assessed disease severity showed significant differences between CTD patients with (MRER: 0.15 ± 0.08, CT-assessed disease severity: 13.0 ± 7.4%) and without ILD (MRER: 0.25 ± 0.06, p = 0.0011; CT-assessed disease severity: 1.6 ± 1.6%, p < 0.0001). MRER and CT-assessed disease severity correlated significantly with pulmonary functional parameters and serum KL-6 in all subjects (0.61 ≤ r ≤ 0.79, p < 0.05). Conclusion: O 2 -enhanced MRI was found to be as useful as thin-section CT for pulmonary functional loss and disease severity assessment of CTD patients with ILD

  18. Comparative evaluation of cerebral aneurysms with selective arterially enhanced CT and DSA

    International Nuclear Information System (INIS)

    Vanderschelden, P.; Flandroy, P.; Dondelinger, R.F.; Martin, D.; Lenelle, J.

    1998-01-01

    The purpose of our study was to compare selective arterially enhanced spiral computed tomographs (ACT) with digital subtraction angiographies (DSA) in the presurgical assessment of cerebral aneurysms. A total of 24 aneurysms in 18 patients were explored in a prospective study by ACT and DSA, using an interactive combined CT-angiography suite. Dimensions of the aneurysm, its relation to the parent vessel, and the aneurysmal index were defined on DSA and on surface-shaded display of 3D reformatted images obtained from ACT. Results were correlated with surgical findings. Three aneurysms suspected on DSA were not confirmed by ACT. One fusiform aneurysm suspected on DSA corresponded to a sacciform aneurysm on ACT. Surgical findings confirmed 20 sacciform aneurysms. The aneurysmal index could be measured in all 20 cases of sacciform aneurysms on ACT and could not be determined with confidence in 55 % of the cases on DSA. DSA and ACT gave identical results in 35 % of cases. In 10 %, the index measured by ACT was superior to that determined by DSA for aneurysms which had a diameter of less than 3 mm. In conclusion, the combination of DSA and ACT improved the results of DSA alone. ACT is a reliable method to measure the aneurysmal index in aneurysms with a diameter superior to 3 mm. (orig.)

  19. Clinical impact of FDG PET-CT on the management of patients with locally advanced cervical carcinoma

    International Nuclear Information System (INIS)

    Fleming, S.; Cooper, R.A.; Swift, S.E.; Thygesen, H.H.; Chowdhury, F.U.; Scarsbrook, A.F.; Patel, C.N.

    2014-01-01

    Aim: To evaluate the impact of staging FDG PET-CT on the initial management of patients with locally advanced cervical carcinoma (LACC) and any prognostic variables predicting survival. Materials and methods: Retrospective analysis of consecutive patients undergoing FDG PET-CT for staging of LACC in a single tertiary referral centre, between April 2008 and August 2011. Comparison was made between MRI and PET-CT findings and any subsequent impact on treatment intent or radiotherapy planning was evaluated. Results: Sixty-three patients underwent FDG PET-CT for initial staging of LACC. Major impact on management was found in 20 patients (32%), a minor impact in five (8%), and no impact in 38 (60%). In those patients where PET-CT had a major impact, 12 had more extensive local nodal involvement, five had occult metastatic disease, two had synchronous tumours, and one patient had equivocal lymph nodes on MRI characterized as negative. PET-positive nodal status at diagnosis was found to be a statistically significant predictor of relapse-free survival (p < 0.05). Conclusion: Staging FDG PET-CT has a major impact on the initial management of approximately one-third of patients with LACC by altering treatment intent and/or radiotherapy planning. PET-defined nodal status is a poor prognostic indicator. - Highlights: • Cervical carcinoma is one of the commonest cancers in women worldwide. • Locally advanced cervical carcinoma is usually treated with chemo-radiotherapy. • FDG PET-CT can have a major impact on management in up to one-third of patients. • It may alter treatment intent or radiotherapy-planning by detecting occult disease. • PET nodal status at diagnosis is an important predictor of relapse-free survival

  20. Computer-aided diagnosis in contrast-enhanced CT colonography: an approach based on contrast

    International Nuclear Information System (INIS)

    Luboldt, Wolfgang; Kroll, Manuela; Vogl, Thomas J.; Mann, Carolin; Vonthein, Reinhard; Stueker, Dietmar; Luz, Oliver; Claussen, Claus D.; Tryon, Cathy L.

    2002-01-01

    Automation in colorectal mass detection is achieved as soon as the voxels representing colorectal masses can be automatically segmented. We tested the Hounsfield (HU) value in intensely contrast enhanced high-resolution CT colonography for automated segmentation of colorectal masses in 18 patients with 35 polyps (28<10 mm, 7 ≥10 mm) and 7 carcinomas. Mean HU values of the colonic wall and masses were determined to deduce a gradient threshold for a segmentation process, which encodes the voxels bordering the colonic lumen with a colour ranging in intensity from 0 to 100% according to the selected gradient threshold range in the volume rendering. The results of the automated segmentation process were superimposed on a virtual double contrast and endoscopic display and validated through correlation with morphology. Mean HU values and their standard deviations for the colonic wall, polyps <10 mm, polyps ≥10 mm and carcinomas were 63±24, 154±38, 116±41 and 108±29 HU, respectively. A gradient threshold ranging from 90 to 160 HU resulted in colour pools in 6 of 7 of polyps ≥10 mm, and 6 of 7 carcinomas that were significant enough to prospectively guide the reader's attention to these masses. Due to the superposition of ''false-positive'' voxels in the projection view, the virtual endoscopic perspective was superior to the virtual double contrast display for controlling the segmentation results. The HU value is promising for automated segmentation of colorectal masses but needs to be combined with morphological parameters to render automated colorectal mass detection more accurate. Further refinements of the method with subsequent analysis of its accuracy, as well as analogue studies with contrast-enhanced MRI, appear warranted. More information at http://www.multiorganscreening.org (orig.)

  1. Effect of tumor volume on the enhancement pattern of parathyroid adenoma on parathyroid four-dimensional CT

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Kyoung [Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Dongguk University Ilsan Hospital, Department of Radiology, Goyang-si (Korea, Republic of); Yun, Tae Jin; Kim, Ji-hoon; Kang, Koung Mi; Choi, Seung Hong; Sohn, Chul-Ho [Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Seoul National University Hospital, Department of Radiology, Jongno-gu, Seoul (Korea, Republic of); Lee, Kyu Eun; Kim, Su-jin [Seoul National University Hospital, Department of Surgery, Seoul (Korea, Republic of); Won, Jae-Kyung [Seoul National University Hospital, Department of Pathology, Seoul (Korea, Republic of)

    2016-05-15

    The purpose of this study is to assess the effect of tumor volume on the enhancement pattern of parathyroid adenoma (PTA) on four-dimensional computed tomography (4D-CT). We analyzed the enhancement patterns of PTA on four-phase 4D-CT in 44 patients. Dependency of the changes of Hounsfield unit values (ΔHU) on the tumor volumes and clinical characteristics was evaluated using linear regression analyses. In addition, an unpaired t test was used to compare ΔHU of PTAs between PTA volume ≥1 cm{sup 3} and <1 cm{sup 3}, thyroid gland, and lymph node. PTA volume based on CT was the strongest factor on the ΔHU{sub Pre} {sub to} {sub Arterial} and ΔHU{sub Arterial} {sub to} {sub Venous} and ΔHU{sub Arterial} {sub to} {sub Delayed} (R {sup 2} = 0.34, 0.25, and 0.32, respectively, P < 0.001 for both). PTA ≥1 cm {sup 3} had statistically significant greater enhancement between the unenhanced phase and the arterial phase than PTA <1 cm {sup 3} (mean values ± standard deviations (SDs) of ΔHU{sub Pre} {sub to} {sub Arterial}, 102.7 ± 33.7 and 57.5 ± 28.8, respectively, P < 0.001). PTA ≥1 cm {sup 3} showed an early washout pattern on the venous phase, whereas PTA <1 cm {sup 3} showed a progressive enhancement pattern on the venous phase (mean values ± SDs of ΔHU{sub Arterial} {sub to} {sub Venous}, -13.2 ± 31.6 and 14.4 ± 32.7, respectively; P = 0.009). The enhancement pattern of PTA on 4D-CT is variable with respect to PTA volume based on CT. Therefore, the enhancement pattern of PTA on 4D-CT requires careful interpretation concerning the tumor volume, especially in cases of PTA <1 cm {sup 3}. (orig.)

  2. Multidetector helical CT plus superparamagnetic iron oxide-enhanced MR imaging for focal hepatic lesions in cirrhotic liver: A comparison with multi-phase CT during hepatic arteriography

    International Nuclear Information System (INIS)

    Yukisawa, Seigo; Okugawa, Hidehiro; Masuya, Yoshio; Okabe, Shinichirou; Fukuda, Hiroyuki; Yoshikawa, Masaharu; Ebara, Masaaki; Saisho, Hiromitsu

    2007-01-01

    The aim of this study was to evaluate multidetector helical computed tomography (MDCT), superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging, and CT arterial portography (CTAP) and CT during hepatic arteriography (CTHA) for the detection and diagnosis of hepatocellular carcinomas (HCC). This included visual correlations of MDCT and SPIO-MR imaging in the detection of HCC using receiver operating characteristic (ROC) analysis. Twenty-five patients with 57 nodular HCCs were retrospectively analyzed. A total of 200 segments, including 49 segments with 57 HCCs, were reviewed independently by three observers. Each observer read four sets of images (set 1, MDCT; set 2, unenhanced and SPIO-enhanced MR images; set 3, combined MDCT and SPIO-enhanced MR images; set 4, combined CTAP and CTHA). The mean Az values representing the diagnostic accuracy for HCCs of sets 1, 2, 3, and 4 were 0.777, 0.814, 0.849, and 0.911, respectively, and there was no significant difference between sets 3 and 4. The sensitivity of set 4 was significantly higher than those of set 3 for all the lesions and for lesions 10 mm or smaller (p < 0.05); however, for lesions larger than 10 mm, the sensitivities of the two sets were similar. No significant difference in positive predictive value and specificity was observed between set 3 and set 4. Combined MDCT and SPIO-enhanced MR imaging may obviate the need for more invasive CTAP and CTHA for the pre-therapeutic evaluation of patients with HCC more than 10 mm

  3. Multi-organ segmentation from multi-phase abdominal CT via 4D graphs using enhancement, shape and location optimization.

    Science.gov (United States)

    Linguraru, Marius George; Pura, John A; Chowdhury, Ananda S; Summers, Ronald M

    2010-01-01

    The interpretation of medical images benefits from anatomical and physiological priors to optimize computer-aided diagnosis (CAD) applications. Diagnosis also relies on the comprehensive analysis of multiple organs and quantitative measures of soft tissue. An automated method optimized for medical image data is presented for the simultaneous segmentation of four abdominal organs from 4D CT data using graph cuts. Contrast-enhanced CT scans were obtained at two phases: non-contrast and portal venous. Intra-patient data were spatially normalized by non-linear registration. Then 4D erosion using population historic information of contrast-enhanced liver, spleen, and kidneys was applied to multi-phase data to initialize the 4D graph and adapt to patient specific data. CT enhancement information and constraints on shape, from Parzen windows, and location, from a probabilistic atlas, were input into a new formulation of a 4D graph. Comparative results demonstrate the effects of appearance and enhancement, and shape and location on organ segmentation.

  4. The influence of the maximal value and peak enhancement value of arterial and venous enhancement curve on CT perfusion parameters and signal-to-noise ratio

    International Nuclear Information System (INIS)

    Ju Haiyue; Gao Sijia; Xu Ke; Wang Qiang

    2007-01-01

    Objective: To explore the influence of the maximal value and peak enhancement value of arterial and venous enhancement curve on CT perfusion parameters and signal-to-noise ratio (SNR). Methods: Seventeen patients underwent brain CT perfusion scanning. All row data were analyzed with perfusion software for 6 times, and get different arterial and venous enhancement curves for each patient. The maximal values and peak enhancement values of each arterial and venous enhancement curves, as well as mean perfusion parameters including cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), permeability surface area product (PS), and their standard deviations (SD) in homolateral white and gray matter were measured and recorded. SNR was calculated by dividing the mean perfusion parameter value by its SD. Pearson correlation analysis and two-tailed paired Student t test were used for statistics. Results: The maximal values and peak enhancement values of arterial and venous curves were correlated with mean SNR CBF , SNR CBV and SNR MTT in both white matter and gray matters (r value range: 0.332-0.922, P PS in white matter(r=0.256, P PS (in both white matter and gray matters) and arterial peak enhancement values, the maximal values and venous peak enhancement values, or between SNR PS (in gray matter) and the maximal values of venous curve(r value range: -0.058-0.210, P>0.05). (2) Mean CBF, CBV and PS values in the group with low venous peak enhancement values were significantly different from the group with high venous peak enhancement values in both white and gray matters (t value range: 3.830-5.337, P 0.05). Conclusions: The mean perfusion parameters and SNR are influenced by the maximal values and peak enhancement values of the arterial and venous curves. Peak enhancement of arterial and venous curves should be adjusted to higher level to make parameter values more reliable and increase the SNR. (authors)

  5. Clinical impact of FDG-PET/CT in the planning of radiotherapy for early-stage Hodgkin lymphoma

    DEFF Research Database (Denmark)

    Hutchings, Martin; Loft, Annika; Hansen, Mads

    2007-01-01

    BACKGROUND: Early-stage Hodgkin lymphoma (HL) has excellent survival rates but carries a high risk of late treatment-related adverse effects. Modern, individualised therapeutic strategies require an accurate determination of the extent of the disease. This study investigated the potential impact...... of 2-[18F]-fluoro-2-deoxy-d-glucose positron emission tomography/computerised tomogrpahy (FDG-PET/CT) in the planning of involved field radiotherapy (IFRT). PATIENTS AND METHODS: Thirty patients received staging FDG-PET/CT before therapy, and IFRT after a short course of ABVD (adriamycin, bleomycin......, vinblastine, dacarbazine) chemotherapy. IFRT planning was performed using only the CT data from the FDG-PET/CT scan. Later, the IFRT planning was performed anew using the FDG-PET/CT data as basis for contouring. RESULTS: In 20 out of 30 patients, the radiotherapy (RT) course was unaffected by the addition...

  6. Additional value of FDG-PET to contrast enhanced-computed tomography (CT) for the diagnosis of mediastinal lymph node metastasis in non-small cell lung cancer. A Japanese multicenter clinical study

    International Nuclear Information System (INIS)

    Kubota, Kazuo; Murakami, Koji; Inoue, Tomio; Itoh, Harumi; Saga, Tsuneo; Shiomi, Susumu; Hatazawa, Jun

    2011-01-01

    This study was a controlled multicenter clinical study to verify the diagnostic effects of additional fluorodeoxyglucose-positron emission tomography (FDG-PET) to contrast-enhanced CT for mediastinal lymph node metastasis in patients with operable non-small cell lung cancer (NSCLC). NSCLC patients with enlarged mediastinal lymph nodes (short diameter, 7-20 mm), confirmed using contrast-enhanced CT, were examined using FDG-PET to detect metastases prior to surgery. The primary endpoint was the accuracy for concomitantly used CT and FDG-PET showing the additional effects of FDG, compared with CT alone. The secondary endpoints were the clinical impact of FDG-PET on therapeutic decisions and adverse reaction from FDG administration. The images were interpreted by investigators at each institution. Moreover, blinded readings were performed by an image interpretation committee independent of the institutions. The gold standard was the pathological diagnosis determined by surgery or biopsy after PET, and patients in whom a pathological diagnosis was not obtained were excluded from the analysis. Among 99 subjects, the results for 81 subjects eligible for analysis showed that the accuracy improved from 69.1% (56/81) for CT alone to 75.3% (61/81) for CT + PET (p=0.404). These findings contributed to treatment decisions in 63.0% (51/81) of the cases, mainly with regard to the selection of the operative procedure. The results of the image interpretation committee showed that the accuracy improved from 64.2% (52/81) (95% confidence interval (CI) 52.8-74.6) for CT to 75.3% (61/81) (95% CI 64.5-84.2) for CT + PET. The accuracy for 106 mediastinal lymph nodes improved significantly from 62.3% (66/106) (95% CI 52.3-71.5) for CT to 79.2% (84/106) (95% CI 70.3-86.5) for CT + PET (p<0.05). We found that no serious adverse drug reactions appeared in any of the 99 patients who received FDG, except for transient mild outliers in the laboratory data for two patients. The addition of FDG

  7. The added value of 68Ga-DOTA-TATE-PET to contrast-enhanced CT for primary site detection in CUP of neuroendocrine origin.

    Science.gov (United States)

    Kazmierczak, Philipp M; Rominger, Axel; Wenter, Vera; Spitzweg, Christine; Auernhammer, Christoph; Angele, Martin K; Rist, Carsten; Cyran, Clemens C

    2017-04-01

    To quantify the additional value of 68 Ga-DOTA-TATE PET/CT in comparison with contrast-enhanced CT alone for primary tumour detection in neuroendocrine cancer of unknown primary (CUP-NET). In total, 38 consecutive patients (27 men, 11 women; mean age 62 years) with histologically proven CUP-NET who underwent a contrast-enhanced 68 Ga-DOTA-TATE PET/CT scan for primary tumour detection and staging between 2010 and 2014 were included in this IRB-approved retrospective study. Two blinded readers independently analysed the contrast-enhanced CT and 68 Ga-DOTA-TATE PET datasets separately and noted from which modality they suspected a primary tumour. Consensus was reached if the results were divergent. Postoperative histopathology (24 patients) and follow-up 68 Ga-DOTA-TATE PET/CT imaging (14 patients) served as the reference standards and statistical measures of diagnostic accuracy were calculated accordingly. The majority of confirmed primary tumours were located in the abdomen (ileum in 19 patients, pancreas in 12, lung in 2, small pelvis in 1). High interobserver agreement was noted regarding the suspected primary tumour site (Cohen's k 0.90, p DOTA-TATE PET demonstrated a significantly higher sensitivity (94 % vs. 63 %, p = 0.005) and a significantly higher accuracy (87 % vs. 68 %, p = 0.003) than contrast-enhanced CT. Ga-DOTA-TATE PET/CT compared with contrast-enhanced CT alone provides an improvement in sensitivity of 50 % and an improvement in accuracy of 30 % in primary tumour detection in CUP-NET. • 68 Ga-DOTA-TATE PET augments the sensitivity of contrast-enhanced CT by 50 % • 68 Ga-DOTA-TATE PET augments the accuracy of contrast-enhanced CT by 30 % • Somatostatin receptor-targeted hybrid imaging optimizes primary tumour detection in CUP-NET.

  8. Impact of low-energy CT imaging on selection of positive oral contrast media concentration.

    Science.gov (United States)

    Patino, Manuel; Murcia, Diana J; Iamurri, Andrea Prochowski; Kambadakone, Avinash R; Hahn, Peter F; Sahani, Dushyant V

    2017-05-01

    To determine to what extent low-energy CT imaging affects attenuation of gastrointestinal tract (GIT) opacified with positive oral contrast media (OCM). Second, to establish optimal OCM concentrations for low-energy diagnostic CT exams. One hundred patients (38 men and 62 women; age 62 ± 11 years; BMI 26 ± 5) with positive OCM-enhanced 120-kVp single-energy CT (SECT), and follow-up 100-kVp acquisitions (group A; n = 50), or 40-70-keV reconstructions from rapid kV switching-single-source dual-energy CT (ssDECT) (group B; n = 50) were included. Luminal attenuation from different GIT segments was compared between exams. Standard dose of three OCM and diluted solutions (75%, 50%, and 25% concentrations) were introduced serially in a gastrointestinal phantom and scanned using SECT (120, 100, and 80 kVp) and DECT (80/140 kVp) acquisitions on a ssDECT scanner. Luminal attenuation was obtained on SECT and DECT images (40-70 keV), and compared to 120-kVp scans with standard OCM concentrations. Luminal attenuation was higher on 100-kVp (328 HU) and on 40-60-keV images (410-924 HU) in comparison to 120-kVp scans (298 HU) in groups A and B (p < 0.05). Phantom: There was an inverse correlation between luminal attenuation and X-ray energy, increasing up to 527 HU on low-kVp and 999 HU on low-keV images (p < 0.05). 25% and 50% diluted OCM solutions provided similar or higher attenuation than 120 kVp, at low kVp and keV, respectively. Low-energy CT imaging increases the attenuation of GIT opacified with positive OCM, permitting reduction of 25%-75% OCM concentration.

  9. Enhancing Resilience to Water-Related Impacts of Climate Change ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Enhancing Resilience to Water-Related Impacts of Climate Change in Uganda's ... technologies (ICTs) can be used to help communities address water stress. ... This work will support the Uganda Ministry of Water and Environment's efforts to ...

  10. Renal streaky artifact during contrast-enhanced abdominal and pelvic CT: Comparison of high versus low osmolality contrast media

    International Nuclear Information System (INIS)

    Kim, Dae Hong; Kim, Jong Chul; Lee, Chung Keun; Shin, Kyoung Suk

    1994-01-01

    Introduction of low osmolality contrast agent(LOCA) has allowed safer, more comfortable contrast-enhanced CT examination, but there has been significant increase in image degradation when evaluating the kidneys due to streaky artifact. The authors reviewed findings of contrast- enhanced abdominal and pelvic computed tomography(CT) to know the difference of renal streaky artifact between a high osmolality contrast agent (HOCA) and LOCA. This study included two hundred contrast-enhanced CT in 200 patients, 100 performed with HOCA(meglumine ioglicate, 150 ml) and 100 performed with LOCA (iopromide,150 ml). The severity of renal streaky artifact was compared between HOCA and LOCA groups. Of the scans performed with HOCA, 40 had no artifact, 52 had grade I artifact, 6 had grade II artifact, and 2 had grade III artifact. Of the scans preformed with LOCA, 23 had no artifact, 44 had grade I artifact, 29 had grade II artifact, and 4 had grade III artifact. There was significant difference in the degree of the streaky artifact depending upon the osmolality of the contrast media used(by χ 2 -test, P=.0001). The results of this study revealed a statistically significant increased incidence of artifacts and distortions of renal image with LOCA when compared with HOCA

  11. Highly sensitive detection of the soft tissues based on refraction contrast by in-plane diffraction-enhanced imaging CT

    International Nuclear Information System (INIS)

    Yuasa, Tetsuya; Hashimoto, Eiko; Maksimenko, Anton; Sugiyama, Hiroshi; Arai, Yoshinori; Shimao, Daisuke; Ichihara, Shu; Ando, Masami

    2008-01-01

    We discuss the recently proposed computed tomography (CT) technique based on refractive effects for biomedical use, which reconstructs the in-plane refractive-index gradient vector field in a cross-sectional plane of interest by detecting the angular deviation of the beam, refracted by a sample, from the incident beam, using the diffraction-enhanced imaging (DEI) method. The CT has advantages for delineating biological weakly absorbing soft tissues over the conventional absorption-contrast CT because of the use of phase sensitive detection. The paper aims to define the imaging scheme rigidly and to demonstrate its efficacy for non-destructive measurement of biomedical soft-tissue samples without imaging agent. We first describe the imaging principle of in-plane DEI-CT from the physico-mathematical viewpoints in detail, and investigate what physical quantities are extracted from the reconstructed images. Then, we introduce the imaging system using the synchrotron radiation as a light source, constructed at beamline BL-14B in KEK, Japan. Finally, we demonstrate the advantage of the refraction-based image for non-destructive analysis of biological sample by investigating the image of human breast cancer tumors obtained using the imaging system. Here, the refraction- and the apparent absorption-based images obtained simultaneously by the in-plane DEI-CT are compared. Also, the conventional absorption-based image obtained using micro-computed tomography (μCT) imaging system is compared with them. Thereby, it is shown that the refraction contrast much more sensitively delineates the soft tissues than the absorption contrast. In addition, the radiologic-histologic correlation study not only validates the efficacy for imaging soft tissues, but also produces the potential that the pathological inspection for the breast cancer tumors may be feasible non-destructively

  12. Comparison of liver volumetry on contrast‐enhanced CT images: one semiautomatic and two automatic approaches

    Science.gov (United States)

    Cai, Wei; He, Baochun; Fang, Chihua

    2016-01-01

    This study was to evaluate the accuracy, consistency, and efficiency of three liver volumetry methods— one interactive method, an in‐house‐developed 3D medical Image Analysis (3DMIA) system, one automatic active shape model (ASM)‐based segmentation, and one automatic probabilistic atlas (PA)‐guided segmentation method on clinical contrast‐enhanced CT images. Forty‐two datasets, including 27 normal liver and 15 space‐occupying liver lesion patients, were retrospectively included in this study. The three methods — one semiautomatic 3DMIA, one automatic ASM‐based, and one automatic PA‐based liver volumetry — achieved an accuracy with VD (volume difference) of −1.69%,−2.75%, and 3.06% in the normal group, respectively, and with VD of −3.20%,−3.35%, and 4.14% in the space‐occupying lesion group, respectively. However, the three methods achieved an efficiency of 27.63 mins, 1.26 mins, 1.18 mins on average, respectively, compared with the manual volumetry, which took 43.98 mins. The high intraclass correlation coefficient between the three methods and the manual method indicated an excellent agreement on liver volumetry. Significant differences in segmentation time were observed between the three methods (3DMIA, ASM, and PA) and the manual volumetry (pvolumetries (ASM and PA) and the semiautomatic volumetry (3DMIA) (pvolumetry agreed well with manual gold standard in both the normal liver group and the space‐occupying lesion group. The ASM‐ and PA‐based automatic segmentation have better efficiency in clinical use. PACS number(s): 87.55.‐x PMID:27929487

  13. Comparison of liver volumetry on contrast-enhanced CT images: one semiautomatic and two automatic approaches.

    Science.gov (United States)

    Cai, Wei; He, Baochun; Fan, Yingfang; Fang, Chihua; Jia, Fucang

    2016-11-08

    This study was to evaluate the accuracy, consistency, and efficiency of three liver volumetry methods- one interactive method, an in-house-developed 3D medical Image Analysis (3DMIA) system, one automatic active shape model (ASM)-based segmentation, and one automatic probabilistic atlas (PA)-guided segmentation method on clinical contrast-enhanced CT images. Forty-two datasets, including 27 normal liver and 15 space-occupying liver lesion patients, were retrospectively included in this study. The three methods - one semiautomatic 3DMIA, one automatic ASM-based, and one automatic PA-based liver volumetry - achieved an accuracy with VD (volume difference) of -1.69%, -2.75%, and 3.06% in the normal group, respectively, and with VD of -3.20%, -3.35%, and 4.14% in the space-occupying lesion group, respectively. However, the three methods achieved an efficiency of 27.63 mins, 1.26 mins, 1.18 mins on average, respectively, compared with the manual volumetry, which took 43.98 mins. The high intraclass correlation coefficient between the three methods and the manual method indicated an excel-lent agreement on liver volumetry. Significant differences in segmentation time were observed between the three methods (3DMIA, ASM, and PA) and the manual volumetry (p volumetries (ASM and PA) and the semiautomatic volumetry (3DMIA) (p < 0.001). The semiautomatic interactive 3DMIA, automatic ASM-based, and automatic PA-based liver volum-etry agreed well with manual gold standard in both the normal liver group and the space-occupying lesion group. The ASM- and PA-based automatic segmentation have better efficiency in clinical use. © 2016 The Authors.

  14. Impact of routine cerebral CT angiography on treatment decisions in infective endocarditis.

    Directory of Open Access Journals (Sweden)

    Marwa Sayed Meshaal

    Full Text Available Infective endocarditis (IE is commonly complicated by cerebral embolization and hemorrhage secondary to intracranial mycotic aneurysms (ICMAs. These complications are associated with poor outcome and may require diagnostic and therapeutic plans to be modified. However, routine screening by brain CT and CT angiography (CTA is not standard practice. We aimed to study the impact of routine cerebral CTA on treatment decisions for patients with IE.From July 2007 to December 2012, we prospectively recruited 81 consecutive patients with definite left-sided IE according to modified Duke's criteria. All patients had routine brain CTA conducted within one week of admission. All patients with ICMA underwent four-vessel conventional angiography. Invasive treatment was performed for ruptured aneurysms, aneurysms ≥ 5 mm, and persistent aneurysms despite appropriate therapy. Surgical clipping was performed for leaking aneurysms if not amenable to intervention.The mean age was 30.43 ± 8.8 years and 60.5% were males. Staph aureus was the most common organism (32.3%. Among the patients, 37% had underlying rheumatic heart disease, 26% had prosthetic valves, 23.5% developed IE on top of a structurally normal heart and 8.6% had underlying congenital heart disease. Brain CT/CTA revealed that 51 patients had evidence of cerebral embolization, of them 17 were clinically silent. Twenty-six patients (32% had ICMA, of whom 15 were clinically silent. Among the patients with ICMAs, 11 underwent endovascular treatment and 2 underwent neurovascular surgery. The brain CTA findings prompted different treatment choices in 21 patients (25.6%. The choices were aneurysm treatment before cardiac surgery rather than at follow-up, valve replacement by biological valve instead of mechanical valve, and withholding anticoagulation in patients with prosthetic valve endocarditis for fear of aneurysm rupture.Routine brain CT/CTA resulted in changes in the treatment plan in a significant

  15. Unusual presentation of a pancreatic insulinoma in helical CT and dynamic contrast-enhanced MR imaging: case report

    Energy Technology Data Exchange (ETDEWEB)

    Iglesias, A.; Arias, M.; Brasa, J. [Unidad de Resonancia Magnetica (Medtec), Hospital Xeral-Cies, Vigo (Spain); Casal, M. [Unidad de Radiologia Intervencionista, Hospital Xeral-Cies, Vigo (Spain); Paramo, C. [Servicio de Endocrinologia, Hospital Xeral-Cies, Vigo (Spain); Fiano, C. [Servicio de Anatomia Patologica, Hospital Xeral-Cies, Vigo (Spain)

    2001-06-01

    Insulinomas are pancreatic neoplasms that can be radiologically characterized typically because of their tendency to present intense and early contrast enhancement with a wash-out phenomenon. In this sense, we report an unusual case of a hypovascular solid pancreatic insulinoma confirmed with surgery and pathologic analysis, in a patient with normal serum insulin levels. In the two-phase helical CT, the mass behaved as a hypodense lesion with respect to the surrounding pancreatic parenchyma during the arterial phase and as a hypointense lesion during the dynamic contrast-enhanced MR imaging. Pathologic examination demonstrated a hypercellular tumor with poor vascularization of intervening stroma which showed prominent amyloid deposits. (orig.)

  16. Unusual presentation of a pancreatic insulinoma in helical CT and dynamic contrast-enhanced MR imaging: case report

    International Nuclear Information System (INIS)

    Iglesias, A.; Arias, M.; Brasa, J.; Casal, M.; Paramo, C.; Fiano, C.

    2001-01-01

    Insulinomas are pancreatic neoplasms that can be radiologically characterized typically because of their tendency to present intense and early contrast enhancement with a wash-out phenomenon. In this sense, we report an unusual case of a hypovascular solid pancreatic insulinoma confirmed with surgery and pathologic analysis, in a patient with normal serum insulin levels. In the two-phase helical CT, the mass behaved as a hypodense lesion with respect to the surrounding pancreatic parenchyma during the arterial phase and as a hypointense lesion during the dynamic contrast-enhanced MR imaging. Pathologic examination demonstrated a hypercellular tumor with poor vascularization of intervening stroma which showed prominent amyloid deposits. (orig.)

  17. CT angiography of intracranial arterial vessels: impact of tube voltage and contrast media concentration on image quality

    International Nuclear Information System (INIS)

    Ramgren, Birgitta; Holtaas, Stig; Siemund, Roger; Dept. of Radiology, Lund Univ., Lund

    2012-01-01

    Background Computed tomography angiography (CTA) of intracranial arteries has high demands on image quality. Important parameters influencing vessel enhancement are injection rate, concentration of contrast media and tube voltage. Purpose To evaluate the impact of an increase of contrast media concentration from 300 to 400 mg iodine/mL (mgI/mL) and the effect of a decrease of tube voltage from 120 to 90 kVp on vessel attenuation and image quality in CT angiography of intracranial arteries. Material and Methods Sixty-three patients were included into three protocol groups: Group I, 300 mgI/mL 120 kVp; Group II, 400 mgI/mL 120 kVp; Group III, 400 mgI/mL 90 kVp. Hounsfield units (HU) were measured in the internal carotid artery (ICA) and the M1 and M2 segments of the middle cerebral artery. Image quality grading was performed regarding M1 and M2 segments, volume rendering and general image impression. Results The difference in mean HU in ICA concerning the effect of contrast media concentration was statistically significant (P = 0.03) in favor of higher concentration. The difference in ICA enhancement due to the effect of tube voltage was statistically significant (P < 0.01) in favor of lower tube voltage. The increase of contrast medium concentration raised the mean enhancement in ICA with 18% and the decrease of tube voltage raised the mean enhancement with 37%. Image quality grading showed a trend towards improved grading for higher contrast concentration and lower tube voltage. Statistically significant better grading was found for the combined effect of both measures except for general impression (P 0.01-0.05). Conclusion The uses of highly concentrated contrast media and low tube voltage are easily performed measures to improve image quality in CTA of intracranial vessel

  18. Reducing radiation dose in liver enhanced CT scan by setting mAs according to plain scan noise

    International Nuclear Information System (INIS)

    Yang Shangwen; He Jian; Yang Xianfeng; Zhou Kefeng; Xin Xiaoyan; Hu Anning; Zhu Bin

    2013-01-01

    Objective: To investigate the feasibility of setting mAs in liver enhanced CT scan according to plain scan noise with fixed mA CT scanner, in order to reduce the radiation dose. Methods: One hundred continuous patients underwent liver enhanced CT scan (group A) prospectively. Two hundred and fifty mAs was used in plain and enhanced CT scans. Noises of plain and venous phase CT images were measured, and the image quality was evaluated. The equation between mAs of enhanced scan and noise of plain scan image was derived. Another 100 continuous patients underwent liver enhanced CT scan (group B). Enhanced scan mAs was calculated from noise on plain scan by using the equation above. Noises on venous phase images were measured and the image quality was measured. Based on body mass index (BMI), patients in groups A and B were divided into three subgroups respectively: BMI < 18.5 kg/m 2 , 18.5 kg/m 2 ≤ BMI < 25.0 kg/m 2 and BMI ≥ 25.0 kg/m 2 . Image quality score was compared with nonparametric rank sum test, CT dose index (CTDI) and effective dose (ED) were measured and compared between each subgroup with 2 independent samples t or t' test. Results: The equation between enhanced scan mAs (mAsX) and plain scan noise (SDp) was as follows: mAsX = mAs1 × [(0.989 × SDp + 1.06) /SDx] 2 , mAs1 = 250 mAs, SDx = 13. In patients with BMI < 18.5 kg/m 2 , ED of group A [(6.86 ± 0.38) mSv, n = 12] was significantly higher than group B [(2.66 ± 0.46) mSv, n = 10)] (t = 18.52, P < 0.01). In patients with 18.5 kg/m 2 ≤ BMI < 25.0 kg/m 2 , ED of group A [(7.08 ± 0.91) mSv, n = 66] was significantly higher than group B [(4.50 ± 1.41) mSv, n = 73] (t' = 10.57, P < 0.01). In patients with BMI ≥ 25.0 kg/m 2 , there was no significant difference between EDs of group A (7.54 ± 0.62 mSv, n = 22) and group B [(8.19 ± 3.16) mSv, n = 17] (t' = 0.89, P = 0.39). Image quality of 5 patients in group A and none in group B did not meet the diagnostic requirement

  19. Clinical Utility of SPECT/CT Imaging Post-Radioiodine Therapy: Does It Enhance Patient Management in Thyroid Cancer?

    Science.gov (United States)

    Hassan, Fahim U; Mohan, Hosahalli K

    2015-12-01

    The aim of this study was to evaluate post-therapy iodine-131 single-photon emission computed tomography/computed tomography ((131)I-SPECT/CT) imaging in comparison to conventional planar (131)I whole-body imaging, and to assess its clinical impact on the management of patients. We retrospectively reviewed planar (131)I whole-body and (131)I-SPECT/CT imaging findings in 67 patients who underwent (131)I therapy for thyroid cancer. Two nuclear medicine physicians reviewed the scans independently. The foci of increased tracer uptake were identified in the neck, thorax and elsewhere. Within the neck, the foci of (131)I-increased uptake were graded qualitatively as probable or definite uptake in thyroid remnants and probable or definite uptake in the lymph nodes. Serum thyroglobulin level, histopathology and other imaging findings served as the reference standard. Of the 67 patients, 57 (85%) had radioiodine avid disease and 10 (15%) demonstrated non-radioiodine avid disease. Overall, post-therapy (131)I-SPECT/CT downstaged lymph node staging in 10 patients and upstaged it in 4 patients. This translated into a change of management for 9/57 (16%) patients with radioiodine avid disease. A change of management was observed in 5/10 patients with non-radioiodine avid disease confirmed in the post-(131)I-SPECT/CT study. Additionally, clinically significant findings such as incidental lung cancer, symptomatic pleural effusion and consolidation were also diagnosed in both groups of patients. In patients with thyroid cancer, (131)I-SPECT/CT is a valuable addition to standard post-therapy planar imaging. SPECT/CT also improved diagnostic confidence and provided crucial clinical information leading to change of management for a significant number of these patients.

  20. CT coronary angiography: impact of adapted statistical iterative reconstruction (ASIR) on coronary stenosis and plaque composition analysis.

    Science.gov (United States)

    Fuchs, Tobias A; Fiechter, Michael; Gebhard, Cathérine; Stehli, Julia; Ghadri, Jelena R; Kazakauskaite, Egle; Herzog, Bernhard A; Husmann, Lars; Gaemperli, Oliver; Kaufmann, Philipp A

    2013-03-01

    To assess the impact of adaptive statistical iterative reconstruction (ASIR) on coronary plaque volume and composition analysis as well as on stenosis quantification in high definition coronary computed tomography angiography (CCTA). We included 50 plaques in 29 consecutive patients who were referred for the assessment of known or suspected coronary artery disease (CAD) with contrast-enhanced CCTA on a 64-slice high definition CT scanner (Discovery HD 750, GE Healthcare). CCTA scans were reconstructed with standard filtered back projection (FBP) with no ASIR (0 %) or with increasing contributions of ASIR, i.e. 20, 40, 60, 80 and 100 % (no FBP). Plaque analysis (volume, components and stenosis degree) was performed using a previously validated automated software. Mean values for minimal diameter and minimal area as well as degree of stenosis did not change significantly using different ASIR reconstructions. There was virtually no impact of reconstruction algorithms on mean plaque volume or plaque composition (e.g. soft, intermediate and calcified component). However, with increasing ASIR contribution, the percentage of plaque volume component between 401 and 500 HU decreased significantly (p ASIR, which has been developed for noise reduction in latest high resolution CCTA scans, can be used reliably without interfering with the plaque analysis and stenosis severity assessment.

  1. Improved accuracy of quantitative parameter estimates in dynamic contrast-enhanced CT study with low temporal resolution

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Mo, E-mail: Sunmo.Kim@rmp.uhn.on.ca [Radiation Medicine Program, Princess Margaret Hospital/University Health Network, Toronto, Ontario M5G 2M9 (Canada); Haider, Masoom A. [Department of Medical Imaging, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5, Canada and Department of Medical Imaging, University of Toronto, Toronto, Ontario M5G 2M9 (Canada); Jaffray, David A. [Radiation Medicine Program, Princess Margaret Hospital/University Health Network, Toronto, Ontario M5G 2M9, Canada and Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5G 2M9 (Canada); Yeung, Ivan W. T. [Radiation Medicine Program, Princess Margaret Hospital/University Health Network, Toronto, Ontario M5G 2M9 (Canada); Department of Medical Physics, Stronach Regional Cancer Centre, Southlake Regional Health Centre, Newmarket, Ontario L3Y 2P9 (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5G 2M9 (Canada)

    2016-01-15

    Purpose: A previously proposed method to reduce radiation dose to patient in dynamic contrast-enhanced (DCE) CT is enhanced by principal component analysis (PCA) filtering which improves the signal-to-noise ratio (SNR) of time-concentration curves in the DCE-CT study. The efficacy of the combined method to maintain the accuracy of kinetic parameter estimates at low temporal resolution is investigated with pixel-by-pixel kinetic analysis of DCE-CT data. Methods: The method is based on DCE-CT scanning performed with low temporal resolution to reduce the radiation dose to the patient. The arterial input function (AIF) with high temporal resolution can be generated with a coarsely sampled AIF through a previously published method of AIF estimation. To increase the SNR of time-concentration curves (tissue curves), first, a region-of-interest is segmented into squares composed of 3 × 3 pixels in size. Subsequently, the PCA filtering combined with a fraction of residual information criterion is applied to all the segmented squares for further improvement of their SNRs. The proposed method was applied to each DCE-CT data set of a cohort of 14 patients at varying levels of down-sampling. The kinetic analyses using the modified Tofts’ model and singular value decomposition method, then, were carried out for each of the down-sampling schemes between the intervals from 2 to 15 s. The results were compared with analyses done with the measured data in high temporal resolution (i.e., original scanning frequency) as the reference. Results: The patients’ AIFs were estimated to high accuracy based on the 11 orthonormal bases of arterial impulse responses established in the previous paper. In addition, noise in the images was effectively reduced by using five principal components of the tissue curves for filtering. Kinetic analyses using the proposed method showed superior results compared to those with down-sampling alone; they were able to maintain the accuracy in the

  2. Appropriate xenon-inhalation speed in xenon-enhanced CT using the end-tidal gas-sampling method

    International Nuclear Information System (INIS)

    Suga, Sadao; Toya, Shigeo; Kawase, Takeshi; Koyama, Hideki; Shiga, Hayao

    1986-01-01

    This report describes some problems when end-tidal xenon gas is substituted for the arterial xenon concentration in xenon-enhanced CT. The authors used a newly developed xenon inhalator with a xenon-gas-concentration analyzer and performed xenon-enhanced CT by means of the ''arterio-venous shunt'' method and the ''end-tidal gas-sampling'' method simultaneously. By the former method, the arterial build-up rate (K) was obtained directly from the CT slices of a blood circuit passing through the phantom. By the latter method, it was calculated from the xenon concentration of end-tidal gas sampled from the mask. The speed of xenon supply was varied between 0.6 - 1.2 L/min. in 11 patients with or without a cerebral lesion. The results revealed that rapid xenon inhalation caused a discrepancy in the arterial K between the ''shunt'' method and the ''end-tidal'' method. This discrepancy may be responsible for the mixing of inhalated gas and expired gas in respiratory dead space, such as the nasal cavity or the mask. The cerebral blood flow was underestimated because of the higher arterial K in the latter method. Too much slow inhalation, however, was timewasting, and it increased the body motion in the subanesthetic state. Therefore, an inhalation speed of the arterial K of as much as 0.2 was ideal to represent the end-tidal xenon concentration for the arterial K in the ''end-tidal gas-sampling'' method. When attention is given to this point, this method may offer a reliable absolute value in xenon-enhanced CT. (author)

  3. The influence of upper limb position on the effect of a contrast agent in chest CT enhancement

    International Nuclear Information System (INIS)

    Feng, Shi-Ting; Wang, Meng; Gao, Zhenhua; Tan, Guosheng; Cai, Huasong; Hu, Xiaoshu; Yang, Jianyong; Li, Zi-Ping

    2013-01-01

    Purpose: To compare the influence of two different upper limb positions on contrast agent effects in chest CT enhancement. Materials and methods: In 142 patients undergoing contrast-enhanced CT chest scanning, an indwelling venous catheter was placed in the right hand and iodinated contrast agent was injected through a high-pressure single syringe pump. The patients were divided into three age groups (<40 years; 40–60 years; and >60 years) and randomly assigned to one of two upper limb position groups: (1) supine position, both upper limbs extended and raised above head in the same horizontal plane as the body; and (2) supine position, both upper limbs raised and crossed on the forehead, with the right arm on top. Differences in mean CT values on the two sides of the thoracic inlet along the right subclavian vein were used to evaluate the effects of the contrast agent. Results: Although contrast agent effects were not significantly different among the three age groups with either limb position, there was a significant difference between patients adopting the second limb positions (Chi-square value was 5.936, P < 0.05). An excellent or good contrast agent effect was observed in 63.08% of patients assuming the first limb position, as compared with 81.69% assuming the second position. Conclusion: For contrast-enhanced CT chest scans, use of the second limb position can reduce retention of the contrast agent in the right axillary vein and the right subclavian vein outside the thorax, increase contrast agent utilization, and decrease artifacts caused by high-density, local retention of the contrast agent

  4. Cerebral blood flow mapping using stable xenon-enhanced CT in sickle cell cerebrovascular disease

    International Nuclear Information System (INIS)

    Numaguchi, Y.; Robinson, A.E.; Carey, J.E.

    1990-01-01

    The cerebral blood flow (CBF) of 25 patients with sickle cell cerebrovascular disease (SCCVD) was examined using a xenon-CT flow mapping method. Brain CT and MR findings were correlated with those of the xenon-CT flow studies. CBF defects on xenon-CT correlated reasonably well with the areas of cortical infarctions on the MR images, but in 27% of the cases, flow defects were slightly larger than the areas of infarctions on the MR images. In deep watershed or basal ganglia infarctions, abnormal CBF was noted about the cerebral cortex near infarctions in 72% of the patients, regardless of infarction sizes on the MR images. However, decreased CBF was recognized in 4 of the 9 children whose MR images were virtually normal. Thus, the extent of flow depletion cannot be predicted accurately by MR imaging alone. Xenon-CT flow mapping proved a safe and reliable procedure for evaluation of the CBF of patients with SCCVD. Although this study is preliminary, it may have a potential in selecting patients for hypertransfusion therapy, as a noninvasive test and for following children with SCCVD during their therapy. Careful correlation of results of CBF with those of MR imaging or of CT is important for objective interpretations of flow mapping images. (orig.)

  5. Objective CT criteria to determine the presence of abnormal basal enhancement in children with suspected tuberculous meningitis

    International Nuclear Information System (INIS)

    Przybojewski, Stefan; Andronikou, Savvas; Wilmshurst, Jo

    2006-01-01

    There are no widely accepted objective criteria to determine the presence of basal enhancement on CT in children with suspected tuberculous meningitis (TBM). To test nine recently described objective CT criteria for the presence of abnormal basal enhancement in children with suspected TBM against the definite diagnosis as determined by cerebrospinal fluid (CSF) culture. CT scans of patients with a clinical suspicion of TBM who had undergone lumbar puncture for CSF culture spanning a period of 4 years were reviewed for the presence of nine recently described criteria for the presence of abnormal basal enhancement. The radiologists were blinded to the final diagnosis based on CSF culture against which the criteria were tested. The criteria have been named: the 'Y-sign', 'linear enhancement', 'double lines', 'infundibular recess of the third', 'ill-defined edge', 'nodular enhancement', 'join the dots', 'contrast filling the cisterns', and 'asymmetry'. A total of 65 patients were included in the study, 34 with culture-proven TBM and 31 with other diagnoses. Four individual criteria had a specificity of 100%, but the sensitivities of these criteria ranged from 15% to 53% only. Three other criteria had specificities of 97% and sensitivities ranging from 62% to 82%. The presence of more than one criterion in the same patient showed a specificity of 97% and sensitivity of 91%. Very high specificity was demonstrated for all nine criteria, including 100% specificity for four individual criteria. Sensitivity was at best 82%, but improved to 91% when more than one criterion was present. These criteria need to be tested for inter- and intraobserver variability to prove their clinical usefulness. (orig.)

  6. Objective CT criteria to determine the presence of abnormal basal enhancement in children with suspected tuberculous meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Przybojewski, Stefan; Andronikou, Savvas [Stellenbosch University Medical School, Department of Radiology, P.O. Box 19063, Tygerberg (South Africa); Wilmshurst, Jo [Red Cross Children' s Hospital and School of Child and Adolescent Health, Department of Paediatric Neurology, Cape Town (South Africa)

    2006-07-15

    There are no widely accepted objective criteria to determine the presence of basal enhancement on CT in children with suspected tuberculous meningitis (TBM). To test nine recently described objective CT criteria for the presence of abnormal basal enhancement in children with suspected TBM against the definite diagnosis as determined by cerebrospinal fluid (CSF) culture. CT scans of patients with a clinical suspicion of TBM who had undergone lumbar puncture for CSF culture spanning a period of 4 years were reviewed for the presence of nine recently described criteria for the presence of abnormal basal enhancement. The radiologists were blinded to the final diagnosis based on CSF culture against which the criteria were tested. The criteria have been named: the 'Y-sign', 'linear enhancement', 'double lines', 'infundibular recess of the third', 'ill-defined edge', 'nodular enhancement', 'join the dots', 'contrast filling the cisterns', and 'asymmetry'. A total of 65 patients were included in the study, 34 with culture-proven TBM and 31 with other diagnoses. Four individual criteria had a specificity of 100%, but the sensitivities of these criteria ranged from 15% to 53% only. Three other criteria had specificities of 97% and sensitivities ranging from 62% to 82%. The presence of more than one criterion in the same patient showed a specificity of 97% and sensitivity of 91%. Very high specificity was demonstrated for all nine criteria, including 100% specificity for four individual criteria. Sensitivity was at best 82%, but improved to 91% when more than one criterion was present. These criteria need to be tested for inter- and intraobserver variability to prove their clinical usefulness. (orig.)

  7. Impact of metal artefacts due to EEG electrodes in brain PET/CT imaging

    International Nuclear Information System (INIS)

    Lemmens, Catherine; Nuyts, Johan; Dupont, Patrick; Montandon, Marie-Louise; Ratib, Osman; Zaidi, Habib

    2008-01-01

    The goal of this study is to investigate the impact of electroencephalogram (EEG) electrodes on the visual quality and quantification of 18 F-FDG PET images in neurological PET/CT examinations. For this purpose, the scans of 20 epilepsy patients with EEG monitoring were used. The CT data were reconstructed with filtered backprojection (FBP) and with a metal artefact reduction (MAR) algorithm. Both data sets were used for CT-based attenuation correction (AC) of the PET data. Also, a calculated AC (CALC) technique was considered. A volume of interest (VOI)-based analysis and a voxel-based quantitative analysis were performed to compare the different AC methods. Images were also evaluated visually by two observers. It was shown with simulations and phantom measurements that from the considered AC methods, the MAR-AC can be used as the reference in this setting. The visual assessment of PET images showed local hot spots outside the brain corresponding to the locations of the electrodes when using FBP-AC. In the brain, no abnormalities were observed. The quantitative analysis showed a very good correlation between PET-FBP-AC and PET-MAR-AC, with a statistically significant positive bias in the PET-FBP-AC images of about 5-7% in most brain voxels. There was also good correlation between PET-CALC-AC and PET-MAR-AC, but in the PET-CALC-AC images, regions with both a significant positive and negative bias were observed. EEG electrodes give rise to local hot spots outside the brain and a positive quantification bias in the brain. However, when diagnosis is made by mere visual assessment, the presence of EEG electrodes does not seem to alter the diagnosis. When quantification is performed, the bias becomes an issue especially when comparing brain images with and without EEG monitoring

  8. Impact of metal artefacts due to EEG electrodes in brain PET/CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lemmens, Catherine; Nuyts, Johan; Dupont, Patrick [Department of Nuclear Medicine and Medical Imaging Center, University Hospital Gasthuisberg and Katholieke Universiteit Leuven, Leuven (Belgium); Montandon, Marie-Louise; Ratib, Osman; Zaidi, Habib [Division of Nuclear Medicine, Geneva University Hospital, CH-1211 Geneva (Switzerland)], E-mail: catherine.lemmens@uz.kuleuven.be

    2008-08-21

    The goal of this study is to investigate the impact of electroencephalogram (EEG) electrodes on the visual quality and quantification of {sup 18}F-FDG PET images in neurological PET/CT examinations. For this purpose, the scans of 20 epilepsy patients with EEG monitoring were used. The CT data were reconstructed with filtered backprojection (FBP) and with a metal artefact reduction (MAR) algorithm. Both data sets were used for CT-based attenuation correction (AC) of the PET data. Also, a calculated AC (CALC) technique was considered. A volume of interest (VOI)-based analysis and a voxel-based quantitative analysis were performed to compare the different AC methods. Images were also evaluated visually by two observers. It was shown with simulations and phantom measurements that from the considered AC methods, the MAR-AC can be used as the reference in this setting. The visual assessment of PET images showed local hot spots outside the brain corresponding to the locations of the electrodes when using FBP-AC. In the brain, no abnormalities were observed. The quantitative analysis showed a very good correlation between PET-FBP-AC and PET-MAR-AC, with a statistically significant positive bias in the PET-FBP-AC images of about 5-7% in most brain voxels. There was also good correlation between PET-CALC-AC and PET-MAR-AC, but in the PET-CALC-AC images, regions with both a significant positive and negative bias were observed. EEG electrodes give rise to local hot spots outside the brain and a positive quantification bias in the brain. However, when diagnosis is made by mere visual assessment, the presence of EEG electrodes does not seem to alter the diagnosis. When quantification is performed, the bias becomes an issue especially when comparing brain images with and without EEG monitoring.

  9. Delayed contrast enhancement imaging of a murine model for ischemia reperfusion with carbon nanotube micro-CT.

    Directory of Open Access Journals (Sweden)

    Laurel M Burk

    Full Text Available We aim to demonstrate the application of free-breathing prospectively gated carbon nanotube (CNT micro-CT by evaluating a myocardial infarction model with a delayed contrast enhancement technique. Evaluation of murine cardiac models using micro-CT imaging has historically been limited by extreme imaging requirements. Newly-developed CNT-based x-ray sources offer precise temporal resolution, allowing elimination of physiological motion through prospective gating. Using free-breathing, cardiac-gated CNT micro-CT, a myocardial infarction model can be studied non-invasively and with high resolution. Myocardial infarction was induced in eight male C57BL/6 mice aged 8-12 weeks. The ischemia reperfusion model was achieved by surgically occluding the LAD artery for 30 minutes followed by 24 hours of reperfusion. Tail vein catheters were placed for contrast administration. Iohexol 300 mgI/mL was administered followed by images obtained in diastole. Iodinated lipid blood pool contrast agent was then administered, followed with images at systole and diastole. Respiratory and cardiac signals were monitored externally and used to gate the scans of free-breathing subjects. Seven control animals were scanned using the same imaging protocol. After imaging, the heart was harvested, cut into 1mm slices and stained with TTC. Post-processing analysis was performed using ITK-Snap and MATLAB. All animals demonstrated obvious delayed contrast enhancement in the left ventricular wall following the Iohexol injection. The blood pool contrast agent revealed significant changes in cardiac function quantified by 3-D volume ejection fractions. All subjects demonstrated areas of myocardial infarct in the LAD distribution on both TTC staining and micro-CT imaging. The CNT micro-CT system aids straightforward, free-breathing, prospectively-gated 3-D murine cardiac imaging. Delayed contrast enhancement allows identification of infarcted myocardium after a myocardial ischemic

  10. Impact of SPECT/CT in imaging inflammation and infection; Wertigkeit der SPECT/CT fuer die nuklearmedizinische Entzuendungsdiagnostik

    Energy Technology Data Exchange (ETDEWEB)

    Linke, R. [Klinikum Bremen-Mitte, Bremen (Germany). Klinik fuer Nuklearmedizin; Kuwert, T. [Erlangen-Nuernberg Univ., Erlangen (Germany). Nuklearmedizinische Klinik mit Poliklinik

    2011-03-15

    Even today infection remains a significant concern, and the diagnosis and localization of infectious foci is an important health issue. As an established infection-imaging modality, nuclear medicine plays a vital health-care role in the diagnosis and subsequent effective treatment of this condition. Several techniques in nuclear medicine significantly aid infection diagnosis, including triple-phase bone scanning, {sup 18}F-FDG-PET and imaging with {sup 111}In-oxine-, {sup 99m}Tc-HMPAO-labeled leukocytes. Each radiopharmaceutical has specific advantages and disadvantages that makes it suitable to diagnose different infectious processes (e.g., soft-tissue sepsis, inflammatory bowel disease, osteomyelitis, occult fever, fever of unknown origin, and infections commonly found in immuno-compromised patients). However, their clinical applications may be limited by the relatively low spatial resolution and the lack of anatomic landmarks of a highly specific tracer with only scarce background uptake to use as a framework for orientation. Anatomic imaging modalities such as CT provide a high-quality assessment of structural abnormalities related to infection, but these structural abnormalities may be unspecific. Furthermore, to detect infection before anatomical changes are present, functional imaging could have some advantages over anatomical imaging. Scintigraphic studies have demonstrated high sensitivity and specificity to an infectious process. Diagnosis and precise delineation of infection may be challenging in certain clinical scenarios, rendering decisions concerning further patient management difficult. The SPECT/CT-technology combines the acquisition of SPECT and CT data with the same imaging device enabling perfect overlay of anatomical and functional images. SPECT/CT imaging data has been shown to be beneficial for many clinical settings such as indeterminate findings in bone scintigraphy, orthopaedic disorders, endocrine, and neuroendocrine tumors. Therefore

  11. 18F-DOPA PET and enhanced CT imaging for congenital hyperinsulinism: initial UK experience from a technologist's perspective.

    Science.gov (United States)

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

    2013-06-01

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

  12. Combined FDG PET/CT imaging for restaging of colorectal cancer patients: impact of image fusion on staging accuracy

    International Nuclear Information System (INIS)

    Strunk, H.; Jaeger, U.; Flacke, S.; Hortling, N.; Bucerius, J.; Joe, A.; Reinhardt, M.; Palmedo, H.

    2005-01-01

    Purpose: To evaluate the diagnostic impact of positron emission tomography (PET) with fluorine-18-labeled deoxy-D-glucose (FDG) combined with non-contrast computed tomography (CT) as PET-CT modality in restaging colorectal cancer patients. Material and methods: In this retrospective study, 29 consecutive patients with histologically proven colorectal cancer (17 female, 12 male, aged 51-76 years) underwent whole body scans in one session on a dual modality PET-CT system (Siemens Biograph) 90 min. after i.v. administration of 370 MBq 18 F-FDG. The CT imaging was performed with 40 mAs, 130 kV, slice-thickness 5 mm and without i.v. contrast administration. PET and CT images were reconstructed with a slice-thickness of 5 mm in coronal, sagittal and transverse planes. During a first step of analysis, PET and CT images were scored blinded and independently by a group of two nuclear medicine physicians and a group of two radiologists, respectively. For this purpose, a five-point-scale was used. The second step of data-analysis consisted of a consensus reading by both groups. During the consensus reading, first a virtual (meaning mental) fusion of PET and CT images and afterwards the 'real' fusion (meaning coregistered) PET-CT images were also scored with the same scale. The imaging results were compared with histopathology findings and the course of disease during further follow-up. Results: The total number of malignant lesions detected with the combined PET/CT were 86. For FDG-PET alone it was n=68, and for CT alone n=65. Comparing PET-CT and PET, concordance was found in 81 of 104 lesions. Discrepancies predominantly occurred in the lung, where PET alone often showed true positive results in lymph nodes and soft tissue masses, where CT often was false negative. Comparing mental fusion and 'real' co-registered images, concordance was found in 94 of 104 lesions. In 13 lesions or, respectively, in 7 of 29 patients, a relevant information was gathered using fused images

  13. Impact of CT attenuation correction method on quantitative respiratory-correlated (4D) PET/CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Nyflot, Matthew J., E-mail: nyflot@uw.edu [Department of Radiation Oncology, University of Washington, Seattle, Washington 98195-6043 (United States); Lee, Tzu-Cheng [Department of Bioengineering, University of Washington, Seattle, Washington 98195-6043 (United States); Alessio, Adam M.; Kinahan, Paul E. [Department of Radiology, University of Washington, Seattle, Washington 98195-6043 (United States); Wollenweber, Scott D.; Stearns, Charles W. [GE Healthcare, Waukesha, Wisconsin 53188 (United States); Bowen, Stephen R. [Department of Radiation Oncology, University of Washington, Seattle, Washington 98195-6043 and Department of Radiology, University of Washington, Seattle, Washington 98195-6043 (United States)

    2015-01-15

    Purpose: Respiratory-correlated positron emission tomography (PET/CT) 4D PET/CT is used to mitigate errors from respiratory motion; however, the optimal CT attenuation correction (CTAC) method for 4D PET/CT is unknown. The authors performed a phantom study to evaluate the quantitative performance of CTAC methods for 4D PET/CT in the ground truth setting. Methods: A programmable respiratory motion phantom with a custom movable insert designed to emulate a lung lesion and lung tissue was used for this study. The insert was driven by one of five waveforms: two sinusoidal waveforms or three patient-specific respiratory waveforms. 3DPET and 4DPET images of the phantom under motion were acquired and reconstructed with six CTAC methods: helical breath-hold (3DHEL), helical free-breathing (3DMOT), 4D phase-averaged (4DAVG), 4D maximum intensity projection (4DMIP), 4D phase-matched (4DMATCH), and 4D end-exhale (4DEXH) CTAC. Recovery of SUV{sub max}, SUV{sub mean}, SUV{sub peak}, and segmented tumor volume was evaluated as RC{sub max}, RC{sub mean}, RC{sub peak}, and RC{sub vol}, representing percent difference relative to the static ground truth case. Paired Wilcoxon tests and Kruskal–Wallis ANOVA were used to test for significant differences. Results: For 4DPET imaging, the maximum intensity projection CTAC produced significantly more accurate recovery coefficients than all other CTAC methods (p < 0.0001 over all metrics). Over all motion waveforms, ratios of 4DMIP CTAC recovery were 0.2 ± 5.4, −1.8 ± 6.5, −3.2 ± 5.0, and 3.0 ± 5.9 for RC{sub max}, RC{sub peak}, RC{sub mean}, and RC{sub vol}. In comparison, recovery coefficients for phase-matched CTAC were −8.4 ± 5.3, −10.5 ± 6.2, −7.6 ± 5.0, and −13.0 ± 7.7 for RC{sub max}, RC{sub peak}, RC{sub mean}, and RC{sub vol}. When testing differences between phases over all CTAC methods and waveforms, end-exhale phases were significantly more accurate (p = 0.005). However, these differences were driven by

  14. No increase in kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin excretion following intravenous contrast enhanced-CT

    Energy Technology Data Exchange (ETDEWEB)

    Kooiman, Judith [Leiden University Medical Center, Department of Thrombosis and Haemostasis, Leiden (Netherlands); Leiden University Medical Center, Department of Nephrology, Leiden (Netherlands); Peppel, Wilke R. van de; Huisman, Menno V. [Leiden University Medical Center, Department of Thrombosis and Haemostasis, Leiden (Netherlands); Sijpkens, Yvo W.J. [Bronovo Hospital, Department of Nephrology, The Hague (Netherlands); Brulez, Harald F.H. [Sint Lucas Andreas Hospital, Department of Nephrology, Amsterdam (Netherlands); Vries, P.M. de [St. Antonius Hospital, Department of Vascular Surgery, Nieuwegein (Netherlands); Nicolaie, Mioara A.; Putter, H. [Leiden University Medical Center, Department of Medical Statistics and Bioinformatics, Leiden (Netherlands); Kooij, W. van der; Kooten, Cees van; Rabelink, Ton J. [Leiden University Medical Center, Department of Nephrology, Leiden (Netherlands)

    2015-07-15

    To analyze kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (N-GAL) excretion post-intravenous contrast enhanced-CT (CE-CT) in patients with chronic kidney disease (CKD). Patients were enrolled in a trial on hydration regimes to prevent contrast-induced acute kidney injury (CI-AKI). Blood and urine samples were taken at baseline, 4 - 6, and 48 - 96 h post CE-CT. Urinary KIM-1 and N-GAL values were normalized for urinary creatinine levels, presented as medians with 2.5 - 97.5 percentiles. Of the enrolled 511 patients, 10 (2 %) were lost to follow-up. CI-AKI occurred in 3.9 % of patients (20/501). Median KIM-1 values were 1.2 (0.1 - 7.7) at baseline, 1.3 (0.1 - 8.6) at 4 - 6 h, and 1.3 ng/mg (0.1 - 8.1) at 48 - 96 h post CE-CT (P = 0.39). Median N-GAL values were 41.0 (4.4 - 3,174.4), 48.9 (5.7 - 3,406.1), and 37.8 μg/mg (3.5 - 3,200.4), respectively (P = 0.07). The amount of KIM-1 and N-GAL excretion in follow-up was similar for patients with and without CI-AKI (P-value KIM-1 0.08, P-value N-GAL 0.73). Neither patient characteristics at baseline including severe CKD, medication use, nor contrast dose were associated with increased excretion of KIM-1 or N-GAL during follow-up. KIM-1 and N-GAL excretion were unaffected by CE-CT both in patients with and without CI-AKI, suggesting that CI-AKI was not accompanied by tubular injury. (orig.)

  15. Application of low dose radiation and low concentration contrast media in enhanced CT scans in children with congenital heart disease.

    Science.gov (United States)

    Liu, Zhimin; Song, Lei; Yu, Tong; Gao, Jun; Zhang, Qifeng; Jiang, Ling; Liu, Yong; Peng, Yun

    2016-09-01

    The aim of this study was to explore the feasibility of using low dose radiation and low concentration contrast media in enhanced CT examinations in children with congenital heart disease. Ninety patients with congenital heart disease were randomly divided into three groups of 30 patients each who underwent contrast-enhanced cardiac scans on a Discovery CT750 HD scanner. Group A received 270 mg I/mL iodixanol, and group B received 320 mg I/mL iodixanol contrast media and was scanned with prospective ECG triggering mode. Group C received 320 mg I/mL iodixanol and was scanned with conventional retrospective ECG gating mode. The same weight-based contrast injection protocol was used for all three groups. Images were reconstructed using a 30% adaptive statistical iterative reconstruction (ASIR) algorithm and a 50% ASIR in groups A and B and a 30% ASIR in group C. The subjective and objective image quality evaluations, diagnostic accuracies, radiation doses and amounts of contrast media in the three groups were measured and compared. All images in the three groups met the diagnostic requirements, with the same diagnostic accuracy and image quality scores greater than 3 in a 4-point scoring system. However, ventricular enhancement and the objective noise, signal-to-noise ratio, contrast-to-noise ratio and subjective image quality scores in group C were better than those in groups A and B (all Pcontrast dose (14% lower than that of groups B and C). Enhanced CT scan images with low dose radiation and low concentration contrast media can meet the diagnostic requirements for examining children with congenital heart disease while reducing the potential risk of radiation damage and contrast-induced nephropathy. © 2016 John Wiley & Sons Ltd.

  16. Change in contrast enhancement of HCC on 1-month follow-up CT after local radiotherapy: An early predictor of final treatment response

    International Nuclear Information System (INIS)

    Kim, Eun Young; Choi, Dongil; Lim, Do Hoon; Lee, Won Jae; Yoo, Byung Chul; Paik, Seung Woon

    2009-01-01

    Background: The purpose of this study was to evaluate the change in contrast enhancement of HCC on 1-month follow-up CT after local radiotherapy (RT) as an early predictor of final treatment response. Materials: Fifty patients who underwent local RT for HCCs had both pre-RT and post-RT CT scans including 1-month follow-up CT. We assessed the final treatment response by using the change in maximal tumor size on 6-12-month follow-up CT scan after RT. We also evaluated the change in tumor enhancement between pre-RT and 1-month follow-up CT scans. Results: A final treatment response was achieved in 27 (54%) of 50 patients, who showed either a complete response (n = 11) or a partial response (n = 16). Compared with non-responsive patients (n = 23), responsive patients showed a significant decrease in tumor enhancement on 1-month follow-up CT after RT in both objective and subjective analyses (each P < 0.001). Conclusion: The change in contrast enhancement of HCC seen on the 1-month follow-up CT in patients after local RT may be used as an early predictor of final treatment response.

  17. Diagnostic performance of fluorodeoxyglucose-positron emission tomography/computed tomography of breast cancer in detecting axillary lymph node metastasis. Comparison with ultrasonography and contrast-enhanced CT

    International Nuclear Information System (INIS)

    Monzawa, Shuichi; Adachi, Shuji; Suzuki, Kayo; Hirokaga, Koichi; Takao, Shintaro; Sakuma, Toshiko; Hanioka, Keisuke

    2009-01-01

    The purpose of this retrospective study was to evaluate the diagnostic performance of positron emission tomography/computed tomography (PET/CT) with fluorine-18-labeled 2-fluoro-2-deoxy-D-glucose (FDG) in comparison with that of ultrasonography and contrast-enhanced computed tomography (CT) in detecting axillary lymph node metastasis in patients with breast cancer. Fifty patients with invasive breast cancer were recruited. They had received no neoadjuvant chemotherapy and underwent PET/CT, ultrasonography and contrast-enhanced CT before mastectomy. The clinical stage was I in 34 patients, II in 15 patients, and III in one patient. The images of these modalities were interpreted in usual practice before surgery and the diagnostic reports were reviewed for analysis. Sensitivity, specificity, positive predictive value, and negative predictive value of each modality were obtained taking histopathological results of axillary lymph node dissection or sentinel lymph node biopsy as the reference standard. Axillary lymph node metastasis was confirmed in 15 of 50 patients by histopathological studies. PET/CT identified lymph node metastasis in three of these 15 patients. The overall sensitivity and specificity, positive predictive value, and negative predictive value of PET/CT in the diagnosis of axillary lymph node metastasis were 20, 97, 75, and 74%, and those of ultrasonography were 33, 94, 71, and 77% and those of contrast-enhanced CT were 27, 97, 80, and 76%, respectively. PET/CT showed poor sensitivity and high specificity in the detection of axillary lymph node metastasis of breast cancer. Diagnostic performance of PET/CT was not superior to that of ultrasonography and contrast-enhanced CT. (author)

  18. 18F-FDG-PET/CT parameters as imaging biomarkers in oral cavity squamous cell carcinoma, is visual analysis of PET and contrast enhanced CT better than the numbers?

    Energy Technology Data Exchange (ETDEWEB)

    Kendi, A.Tuba, E-mail: ayse.kendi@emory.edu [Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA (United States); Corey, Amanda [Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA (United States); Magliocca, Kelly R. [Department of Pathology, Emory University, Atlanta, GA (United States); Nickleach, Dana C. [Biostatistics & Bioinformatics Shared Resource at Winship Cancer Institute of Emory University, Atlanta, GA (United States); Galt, James [Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA (United States); Switchenko, Jeffrey M. [Biostatistics & Bioinformatics Shared Resource at Winship Cancer Institute of Emory University, Atlanta, GA (United States); El-Deiry, Mark W.; Wadsworth, J. Trad [Otolaryngology Head and Neck Surgery, Emory University, Atlanta, GA (United States); Hudgins, Patricia A. [Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA (United States); Saba, Nabil F. [Hematology Oncology, Winship Cancer Institute of Emory University, Atlanta, GA (United States); Schuster, David M. [Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA (United States)

    2015-06-15

    Highlights: • Highlights of our study were the significant association of higher T stage of oral cavity squamous cell carcinoma with PET/CT parameters. • This could be an important finding in cases where it is difficult to decide on T stage by CT only. • We found a significant association between ring/heterogeneous enhancement pattern of (either primary or nodal or both) oral cavity squamous cell carcinoma at contrast enhanced CT and poor prognosis. • This could be related to hypoxia, which is a known reason for therapy resistance. Hence therapies can be tailored in the feature depending on enhancement pattern on contrast enhanced CT. - Abstract: Purpose: This study was designed to seek associations between positron emission tomography/computed tomography (PET/CT) parameters, contrast enhanced neck computed tomography (CECT) and pathological findings, and to determine the potential prognostic value of PET/CT and CECT parameters in oral cavity squamous cell carcinoma (OCSCC). Materials and method: 36 OCSCC patients underwent staging PET/CT and 30/36 of patients had CECT. PET/CT parameters were measured for the primary tumor and the hottest involved node, including maximum, mean, and peak standardized uptake values (SUV max, SUV mean, and SUV peak), metabolic tumor volume (MTV), total lesion glycolysis (TLG), standardized added metabolic activity (SAM), and normalized standardized added metabolic activity (N SAM). Qualitative assessment of PET/CT and CECT were also performed. Pathological outcomes included: perineural invasion, lymphovascular invasion, nodal extracapsular spread, grade, pathologic T and N stages. Multivariable logistic regression models were fit for each parameter and outcome adjusting for potentially confounding variables. Multivariable Cox proportional hazards models were used for progression free survival (PFS), locoregional recurrence free survival (LRFS), overall survival (OS) and distant metastasis free survival (DMFS). Results: In

  19. 18F-FDG-PET/CT parameters as imaging biomarkers in oral cavity squamous cell carcinoma, is visual analysis of PET and contrast enhanced CT better than the numbers?

    International Nuclear Information System (INIS)

    Kendi, A.Tuba; Corey, Amanda; Magliocca, Kelly R.; Nickleach, Dana C.; Galt, James; Switchenko, Jeffrey M.; El-Deiry, Mark W.; Wadsworth, J. Trad; Hudgins, Patricia A.; Saba, Nabil F.; Schuster, David M.

    2015-01-01

    Highlights: • Highlights of our study were the significant association of higher T stage of oral cavity squamous cell carcinoma with PET/CT parameters. • This could be an important finding in cases where it is difficult to decide on T stage by CT only. • We found a significant association between ring/heterogeneous enhancement pattern of (either primary or nodal or both) oral cavity squamous cell carcinoma at contrast enhanced CT and poor prognosis. • This could be related to hypoxia, which is a known reason for therapy resistance. Hence therapies can be tailored in the feature depending on enhancement pattern on contrast enhanced CT. - Abstract: Purpose: This study was designed to seek associations between positron emission tomography/computed tomography (PET/CT) parameters, contrast enhanced neck computed tomography (CECT) and pathological findings, and to determine the potential prognostic value of PET/CT and CECT parameters in oral cavity squamous cell carcinoma (OCSCC). Materials and method: 36 OCSCC patients underwent staging PET/CT and 30/36 of patients had CECT. PET/CT parameters were measured for the primary tumor and the hottest involved node, including maximum, mean, and peak standardized uptake values (SUV max, SUV mean, and SUV peak), metabolic tumor volume (MTV), total lesion glycolysis (TLG), standardized added metabolic activity (SAM), and normalized standardized added metabolic activity (N SAM). Qualitative assessment of PET/CT and CECT were also performed. Pathological outcomes included: perineural invasion, lymphovascular invasion, nodal extracapsular spread, grade, pathologic T and N stages. Multivariable logistic regression models were fit for each parameter and outcome adjusting for potentially confounding variables. Multivariable Cox proportional hazards models were used for progression free survival (PFS), locoregional recurrence free survival (LRFS), overall survival (OS) and distant metastasis free survival (DMFS). Results: In

  20. Hepatic and vascular enhancement at dual-phase helical CT: comparison of Iobitridol 300 and Iohexol 300 in a prospective randomized study

    International Nuclear Information System (INIS)

    Legmann, P.; Vignaux, O.; Bahurel, H.; Oudjit, A.; Coste, J.

    2001-01-01

    The purpose of this study was to determine hepatic and vascular enhancement, clinical tolerance, and iconographic quality of Iobitridol (300 mg/ml) at dual-phase helical CT and to compare it with Iohexol (300 mg/ml). One hundred forty-six patients were randomly divided into two groups. Each group received 120 ml of Iohexol (group A) or Iobitridol (group B). Mean enhancement of liver, aorta and portal vein was obtained at the arterial phase and at the portal-venous phase. Overall image quality was assessed by two independent blinded investigators. Adverse reactions were recorded. There were no significant differences in demographic characteristics and distribution of patient intrinsic parameters between the two groups, except for blood pressure but without statistical correlation between the difference in blood pressure and the impact on enhancement measurements. There was no significant difference in clinical tolerance and image quality. Mean liver as well as aortic and portal vein enhancement measurements did not show any significant difference. Iobitridol compares favorably with Iohexol. Both products have similar safety, tolerance, and efficacy. Both contrast media have equivalent blood pool concentration and interstitial compartment diffusion. (orig.)

  1. Hepatic and vascular enhancement at dual-phase helical CT: comparison of Iobitridol 300 and Iohexol 300 in a prospective randomized study

    Energy Technology Data Exchange (ETDEWEB)

    Legmann, P.; Vignaux, O.; Bahurel, H.; Oudjit, A. [Dept. of Radiology, Universite Rene Descartes, Paris (France); Coste, J. [Dept. of Biostatistics and Epidemiology, Universite Rene Descartes, Paris (France)

    2001-11-01

    The purpose of this study was to determine hepatic and vascular enhancement, clinical tolerance, and iconographic quality of Iobitridol (300 mg/ml) at dual-phase helical CT and to compare it with Iohexol (300 mg/ml). One hundred forty-six patients were randomly divided into two groups. Each group received 120 ml of Iohexol (group A) or Iobitridol (group B). Mean enhancement of liver, aorta and portal vein was obtained at the arterial phase and at the portal-venous phase. Overall image quality was assessed by two independent blinded investigators. Adverse reactions were recorded. There were no significant differences in demographic characteristics and distribution of patient intrinsic parameters between the two groups, except for blood pressure but without statistical correlation between the difference in blood pressure and the impact on enhancement measurements. There was no significant difference in clinical tolerance and image quality. Mean liver as well as aortic and portal vein enhancement measurements did not show any significant difference. Iobitridol compares favorably with Iohexol. Both products have similar safety, tolerance, and efficacy. Both contrast media have equivalent blood pool concentration and interstitial compartment diffusion. (orig.)

  2. 3D imaging of hydrogen assisted cracking in metals using refraction enhanced synchrotron CT

    Energy Technology Data Exchange (ETDEWEB)

    Laquai, Rene; Mueller, Bernd R.; Bruno, Giovanni [BAM Federal Institute for Materials Research and Testing, Berlin (Germany). Div. 8.5 Micro-NDT; Schaupp, Thomas; Griesche, Axel; Kannengiesser, Thomas [BAM Federal Institute for Materials Research and Testing, Berlin (Germany). Div. 9.4 Weld Mechanics

    2015-07-01

    Hydrogen in metals can cause a degradation of the mechanical properties with possible subsequent hydrogen assisted cracking (HAC). Though, the mechanism of HAC is not completely understood yet and thus suitable methods for in situ investigations to characterise the crack formation are needed. X-ray computed tomography (CT) is a well-known tool for analysing these properties. However, the effective resolution of the detector system limits the detection of small defects by CT. Analyser based imaging (ABI) takes advantage of X-ray refraction at interfaces between volumes of different density, i.e. of cracks, pores, inclusions, etc., within the sample to detect defects smaller than the resolution of the detector system. In this study, measurements on an aluminium alloy weld showed that ABI allows us to resolve the 3D structure of cracks undetected by absorption based CT. Prospective investigations will analyse HAC in steels.

  3. 3D imaging of hydrogen assisted cracking in metals using refraction enhanced synchrotron CT

    International Nuclear Information System (INIS)

    Laquai, Rene; Mueller, Bernd R.; Bruno, Giovanni; Schaupp, Thomas; Griesche, Axel; Kannengiesser, Thomas

    2015-01-01

    Hydrogen in metals can cause a degradation of the mechanical properties with possible subsequent hydrogen assisted cracking (HAC). Though, the mechanism of HAC is not completely understood yet and thus suitable methods for in situ investigations to characterise the crack formation are needed. X-ray computed tomography (CT) is a well-known tool for analysing these properties. However, the effective resolution of the detector system limits the detection of small defects by CT. Analyser based imaging (ABI) takes advantage of X-ray refraction at interfaces between volumes of different density, i.e. of cracks, pores, inclusions, etc., within the sample to detect defects smaller than the resolution of the detector system. In this study, measurements on an aluminium alloy weld showed that ABI allows us to resolve the 3D structure of cracks undetected by absorption based CT. Prospective investigations will analyse HAC in steels.

  4. Precision Medicine for Advanced Pancreas Cancer: The Individualized Molecular Pancreatic Cancer Therapy (IMPaCT) Trial.

    Science.gov (United States)

    Chantrill, Lorraine A; Nagrial, Adnan M; Watson, Clare; Johns, Amber L; Martyn-Smith, Mona; Simpson, Skye; Mead, Scott; Jones, Marc D; Samra, Jaswinder S; Gill, Anthony J; Watson, Nicole; Chin, Venessa T; Humphris, Jeremy L; Chou, Angela; Brown, Belinda; Morey, Adrienne; Pajic, Marina; Grimmond, Sean M; Chang, David K; Thomas, David; Sebastian, Lucille; Sjoquist, Katrin; Yip, Sonia; Pavlakis, Nick; Asghari, Ray; Harvey, Sandra; Grimison, Peter; Simes, John; Biankin, Andrew V

    2015-05-01

    Personalized medicine strategies using genomic profiling are particularly pertinent for pancreas cancer. The Individualized Molecular Pancreatic Cancer Therapy (IMPaCT) trial was initially designed to exploit results from genome sequencing of pancreatic cancer under the auspices of the International Cancer Genome Consortium (ICGC) in Australia. Sequencing revealed small subsets of patients with aberrations in their tumor genome that could be targeted with currently available therapies. The pilot stage of the IMPaCT trial assessed the feasibility of acquiring suitable tumor specimens for molecular analysis and returning high-quality actionable genomic data within a clinically acceptable timeframe. We screened for three molecular targets: HER2 amplification; KRAS wild-type; and mutations in DNA damage repair pathways (BRCA1, BRCA2, PALB2, ATM). Tumor biopsy and archived tumor samples were collected from 93 patients and 76 were screened. To date 22 candidate cases have been identified: 14 KRAS wild-type, 5 cases of HER2 amplification, 2 mutations in BRCA2, and 1 ATM mutation. Median time from consent to the return of validated results was 21.5 days. An inability to obtain a biopsy or insufficient tumor content in the available specimen were common reasons for patient exclusion from molecular analysis while deteriorating performance status prohibited a number of patients from proceeding in the study. Documenting the feasibility of acquiring and screening biospecimens for actionable molecular targets in real time will aid other groups embarking on similar trials. Key elements include the need to better prescreen patients, screen more patients, and offer more attractive clinical trial options. ©2015 American Association for Cancer Research.

  5. SU-G-206-02: Impact of Focal Spot Sizes On CT Image Quality

    International Nuclear Information System (INIS)

    Bache, S; Rong, J

    2016-01-01

    Purpose: To quantify a radiology team’s assessment of image quality differences between two CT scanner models currently in clinical use, with emphasis on spatial resolution that could be impacted by focal spot size. Methods: Modulation Transfer Functions (MTF) measurements were performed by scanning the impulse source insert module of the Catphan 600 at 120/140 kVp with both large (LFS) and small (SFS) focal spots and reconstructed to 2.5mm and 5.0mm thicknesses on a GE Discovery CT750 HD and a LightSpeed VCT CT scanner. MTFs were calculated by summing the 2D PSF along one-dimension to obtain line-spread-function (LSF), and calculating the Fourier Transform of the zero-padded and background corrected LSF. Spatial resolution performance was evaluated by comparing MTF curves, 50% and 10% MTF cutoff, and total area under the MTF curve (AUC). In addition, images of the Catphan high-contrast module and a Kagaku anthropomorphic body phantom were acquired from the HD scanner for visual comparisons. Results: For each scanner model, SFS was superior to LFS spatial resolution with respect to 50%/10% MTF cutoff and AUC. For the HD, 50%/10% cutoff was 4.29/7.22cm-1 for the LFS and 4.43/7.45cm-1 for the SFS. VCT outperformed HD, with 50%/10% cutoff of 4.40/7.29 cm-1 for LFS and 4.62/7.47cm-1 for SFS. Scanner model performance in order of decreasing AUC performance was VCT SFS (7.43), HD SFS (7.20), VCT LFS (7.09) and HD LFS (6.93). Visual evaluations of Kagaku phantom images confirmed that VCT outperformed HD. Conclusion: VCT outperformed HD and small focal spot is desired for either model over large focal spot in term of spatial resolution – in agreement with radiologist feedback of overall image quality. In-depth evaluations of clinical impact and focal spot selection mechanisms is currently being assessed.

  6. A New Adaptive Gamma Correction Based Algorithm Using DWT-SVD for Non-Contrast CT Image Enhancement.

    Science.gov (United States)

    Kallel, Fathi; Ben Hamida, Ahmed

    2017-12-01

    The performances of medical image processing techniques, in particular CT scans, are usually affected by poor contrast quality introduced by some medical imaging devices. This suggests the use of contrast enhancement methods as a solution to adjust the intensity distribution of the dark image. In this paper, an advanced adaptive and simple algorithm for dark medical image enhancement is proposed. This approach is principally based on adaptive gamma correction using discrete wavelet transform with singular-value decomposition (DWT-SVD). In a first step, the technique decomposes the input medical image into four frequency sub-bands by using DWT and then estimates the singular-value matrix of the low-low (LL) sub-band image. In a second step, an enhanced LL component is generated using an adequate correction factor and inverse singular value decomposition (SVD). In a third step, for an additional improvement of LL component, obtained LL sub-band image from SVD enhancement stage is classified into two main classes (low contrast and moderate contrast classes) based on their statistical information and therefore processed using an adaptive dynamic gamma correction function. In fact, an adaptive gamma correction factor is calculated for each image according to its class. Finally, the obtained LL sub-band image undergoes inverse DWT together with the unprocessed low-high (LH), high-low (HL), and high-high (HH) sub-bands for enhanced image generation. Different types of non-contrast CT medical images are considered for performance evaluation of the proposed contrast enhancement algorithm based on adaptive gamma correction using DWT-SVD (DWT-SVD-AGC). Results show that our proposed algorithm performs better than other state-of-the-art techniques.

  7. Diagnostic and prognostic impact of 18F-FDG PET/CT in follicular lymphoma

    International Nuclear Information System (INIS)

    Le Dortz, Ludovic; Garin, Etienne; Guibert, Sophie de; Houot, Roch; Bayat, Sahar; Cuggia, Marc; Devillers, Anne; Le Jeune, Florence; Bahri, Haifa; Barge, Marie-Luce; Rolland, Yan; Lamy, Thierry

    2010-01-01

    The aim of this study was to assess the usefulness of positron emission tomography/computed tomography in staging, prognosis evaluation and restaging of patients with follicular lymphoma. A retrospective study was performed on 45 patients with untreated biopsy-proven follicular lymphoma who underwent 18 F-fluorodeoxyglucose PET/CT (FDG PET/CT) and CT before and after chemoimmunotherapy induction treatment (rituximab combined with cyclophosphamide, doxorubicin, vincristine and prednisone). PET/CT detected more nodal (+51%) and extranodal (+89%) lesions than CT. PET/CT modified Ann Arbor staging in eight patients (18%). Five patients (11%) initially considered as being early stage (I/II) were eventually treated as advanced stage (III/IV). In this study, an initial PET/CT prognostic score was significantly more accurate than the Follicular Lymphoma International Prognostic Index score in identifying patients with poor prognosis (i.e. patients with incomplete therapeutic response or early relapse). The accuracy of PET/CT for therapeutic response assessment was higher than that of CT (0.97 vs 0.64), especially due to its ability to identify inactive residual masses. In addition, post-treatment PET/CT was able to predict patients' outcomes. The median progression-free survival was 48 months in the PET/CT-negative group as compared with 17.2 months for the group with residual uptake (p -4 ). FDG PET/CT is useful for staging and assessing the prognosis and therapeutic response of patients with follicular lymphoma. (orig.)

  8. SU-E-J-154: Image Quality Assessment of Contrast-Enhanced 4D-CT for Pancreatic Adenocarcinoma in Radiotherapy Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, W; Xue, M; Patel, K; Regine, W; Wang, J; D’Souza, W; Lu, W [University of Maryland School of Medicine, Baltimore, MD (United States); Kang, M [University of Maryland School of Medicine, Baltimore, MD (United States); Yeungnam University Medical Center, Daegu, Daegu (Korea, Republic of); Klahr, P [Philips Healthcare, Highland Heights, OH (United States)

    2015-06-15

    Purpose: This study presents quantitative and qualitative assessment of the image qualities in contrast-enhanced (CE) 3D-CT, 4D-CT and CE 4D-CT to identify feasibility for replacing the clinical standard simulation with a single CE 4D-CT for pancreatic adenocarcinoma (PDA) in radiotherapy simulation. Methods: Ten PDA patients were enrolled and underwent three CT scans: a clinical standard pair of CE 3D-CT immediately followed by a 4D-CT, and a CE 4D-CT one week later. Physicians qualitatively evaluated the general image quality and regional vessel definitions and gave a score from 1 to 5. Next, physicians delineated the contours of the tumor (T) and the normal pancreatic parenchyma (P) on the three CTs (CE 3D-CT, 50% phase for 4D-CT and CE 4D-CT), then high density areas were automatically removed by thresholding at 500 HU and morphological operations. The pancreatic tumor contrast-to-noise ratio (CNR), signal-tonoise ratio (SNR) and conspicuity (C, absolute difference of mean enhancement levels in P and T) were computed to quantitatively assess image quality. The Wilcoxon rank sum test was used to compare these quantities. Results: In qualitative evaluations, CE 3D-CT and CE 4D-CT scored equivalently (4.4±0.4 and 4.3±0.4) and both were significantly better than 4D-CT (3.1±0.6). In quantitative evaluations, the C values were higher in CE 4D-CT (28±19 HU, p=0.19 and 0.17) than the clinical standard pair of CE 3D-CT and 4D-CT (17±12 and 16±17 HU, p=0.65). In CE 3D-CT and CE 4D-CT, mean CNR (1.8±1.4 and 1.8±1.7, p=0.94) and mean SNR (5.8±2.6 and 5.5±3.2, p=0.71) both were higher than 4D-CT (CNR: 1.1±1.3, p<0.3; SNR: 3.3±2.1, p<0.1). The absolute enhancement levels for T and P were higher in CE 4D-CT (87, 82 HU) than in CE 3D-CT (60, 56) and 4DCT (53, 70). Conclusions: The individually optimized CE 4D-CT is feasible and achieved comparable image qualities to the clinical standard simulation. This study was supported in part by Philips Healthcare.

  9. Malignant focal hepatic lesions complicating underlying liver disease: dual-phase contrast-enhanced spiral CT sensitivity and specificity in orthotopic liver transplant patients

    International Nuclear Information System (INIS)

    Mortele, K.J.; De Keukeleire, K.; Praet, M.; Van Vlierberghe, H.; Hemptinne, B. de; Ros, P.R.

    2001-01-01

    The aim of this study was to determine the accuracy of contrast-enhanced biphasic spiral CT as a screening tool in the preoperative evaluation of orthotopic liver transplant (OLT) patients. Spiral-CT examinations were performed before liver transplantation in 53 patients. Scans were retrospectively reviewed and compared with pathologic findings in fresh-sectioned livers. When findings between spiral CT and pathology were discordant, formalized livers were reexamined with lesion-by lesion evaluation. Fresh pathologic evaluation revealed 23 liver lesions (16 HCC, 7 macro-regenerative nodules). Malignancy was identified in 13 of 53 patients (24.5%). Pre-transplantation spiral CT depicted 27 liver lesions (23 HCC, 4 macro-regenerative nodules). Malignancy was suspected in 14 patients (26.4%). In 10 of 53 (18.9%), spiral CT and pathologic evaluation were discordant. Subsequent retrospective pathologic evaluation showed malignancy in 4 additional patients. Spiral CT compared with the retrospective pathologic findings revealed 36 real-negative, 14 real-positive, 0 false-positive, and 3 false-negative patients with malignancy. Sensitivity and specificity of spiral CT in detection of malignancy was 82 and 100%, respectively. Contrast-enhanced biphasic spiral CT is an accurate technique in the evaluation of patients preceding OLT. Routine fresh-sectioned liver pathologic findings are not as sensitive as previously estimated. (orig.)

  10. Quantitative analysis of dynamic airway changes after methacholine and salbutamol inhalation on xenon-enhanced chest CT

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang Joon; Goo, Jin Mo; Kim, Jong Hyo; Park, Eun-Ah [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul National University College of Medicine, Institute of Radiation Medicine, Medical Research Center, Seoul (Korea, Republic of); Lee, Chang Hyun [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul National University College of Medicine, Institute of Radiation Medicine, Medical Research Center, Seoul (Korea, Republic of); Seoul National University Hospital, Healthcare Gangnam Center, Seoul (Korea, Republic of); Jung, Jae-Woo; Park, Heung-Woo [Seoul National University College of Medicine, Department of Internal Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, Institute of Allergy and Clinical Immunology, Seoul (Korea, Republic of); Cho, Sang-Heon [Seoul National University Hospital, Healthcare Gangnam Center, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Internal Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, Institute of Allergy and Clinical Immunology, Seoul (Korea, Republic of)

    2012-11-15

    To investigate the dynamic changes in airways in response to methacholine and salbutamol inhalation and to correlate the xenon ventilation index on xenon-enhanced chest CTs in asthmatics. Thirty-one non-smokers (6 normal, 25 asthmatics) underwent xenon-enhanced chest CT and pulmonary function tests. Images were obtained at three stages (basal state, after methacholine inhalation and after salbutamol inhalation), and the total xenon ventilation index (TXVI) as well as airway values were measured and calculated. The repeated measures ANOVA and Spearman's correlation coefficient were used for statistical analysis. TXVI in the normal group did not significantly change (P > 0.05) with methacholine and salbutamol. For asthmatics, however, the TXVI significantly decreased after methacholine inhalation and increased after salbutamol inhalation (P < 0.05). Of the airway parameters, the airway inner area (IA) significantly increased after salbutamol inhalation in all airways (P < 0.01) in asthmatics. Airway IA, wall thickness and wall area percentage did not significantly decrease after methacholine inhalation (P > 0.05). IA of the large airways was well correlated with basal TXVI, FEV{sub 1} and FVC (P < 0.05). Airway IA is the most reliable parameter for reflecting the dynamic changes after methacholine and salbutamol inhalation, and correlates well with TXVI in asthmatics on xenon-enhanced CT. (orig.)

  11. Quantifying the impact of respiratory-gated 4D CT acquisition on thoracic image quality: A digital phantom study

    International Nuclear Information System (INIS)

    Bernatowicz, K.; Knopf, A.; Lomax, A.; Keall, P.; Kipritidis, J.; Mishra, P.

    2015-01-01

    Purpose: Prospective respiratory-gated 4D CT has been shown to reduce tumor image artifacts by up to 50% compared to conventional 4D CT. However, to date no studies have quantified the impact of gated 4D CT on normal lung tissue imaging, which is important in performing dose calculations based on accurate estimates of lung volume and structure. To determine the impact of gated 4D CT on thoracic image quality, the authors developed a novel simulation framework incorporating a realistic deformable digital phantom driven by patient tumor motion patterns. Based on this framework, the authors test the hypothesis that respiratory-gated 4D CT can significantly reduce lung imaging artifacts. Methods: Our simulation framework synchronizes the 4D extended cardiac torso (XCAT) phantom with tumor motion data in a quasi real-time fashion, allowing simulation of three 4D CT acquisition modes featuring different levels of respiratory feedback: (i) “conventional” 4D CT that uses a constant imaging and couch-shift frequency, (ii) “beam paused” 4D CT that interrupts imaging to avoid oversampling at a given couch position and respiratory phase, and (iii) “respiratory-gated” 4D CT that triggers acquisition only when the respiratory motion fulfills phase-specific displacement gating windows based on prescan breathing data. Our framework generates a set of ground truth comparators, representing the average XCAT anatomy during beam-on for each of ten respiratory phase bins. Based on this framework, the authors simulated conventional, beam-paused, and respiratory-gated 4D CT images using tumor motion patterns from seven lung cancer patients across 13 treatment fractions, with a simulated 5.5 cm 3 spherical lesion. Normal lung tissue image quality was quantified by comparing simulated and ground truth images in terms of overall mean square error (MSE) intensity difference, threshold-based lung volume error, and fractional false positive/false negative rates. Results: Averaged

  12. Quantifying the impact of respiratory-gated 4D CT acquisition on thoracic image quality: A digital phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Bernatowicz, K., E-mail: kingab@student.ethz.ch; Knopf, A.; Lomax, A. [Center for Proton Therapy, Paul Scherrer Institute, Villigen PSI 5232, Switzerland and Department of Physics, ETH Zürich, Zürich 8092 (Switzerland); Keall, P.; Kipritidis, J., E-mail: john.kipritidis@sydney.edu.au [Radiation Physics Laboratory, Sydney Medical School, University of Sydney, Sydney, NSW 2006 (Australia); Mishra, P. [Brigham and Womens Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115 (United States)

    2015-01-15

    Purpose: Prospective respiratory-gated 4D CT has been shown to reduce tumor image artifacts by up to 50% compared to conventional 4D CT. However, to date no studies have quantified the impact of gated 4D CT on normal lung tissue imaging, which is important in performing dose calculations based on accurate estimates of lung volume and structure. To determine the impact of gated 4D CT on thoracic image quality, the authors developed a novel simulation framework incorporating a realistic deformable digital phantom driven by patient tumor motion patterns. Based on this framework, the authors test the hypothesis that respiratory-gated 4D CT can significantly reduce lung imaging artifacts. Methods: Our simulation framework synchronizes the 4D extended cardiac torso (XCAT) phantom with tumor motion data in a quasi real-time fashion, allowing simulation of three 4D CT acquisition modes featuring different levels of respiratory feedback: (i) “conventional” 4D CT that uses a constant imaging and couch-shift frequency, (ii) “beam paused” 4D CT that interrupts imaging to avoid oversampling at a given couch position and respiratory phase, and (iii) “respiratory-gated” 4D CT that triggers acquisition only when the respiratory motion fulfills phase-specific displacement gating windows based on prescan breathing data. Our framework generates a set of ground truth comparators, representing the average XCAT anatomy during beam-on for each of ten respiratory phase bins. Based on this framework, the authors simulated conventional, beam-paused, and respiratory-gated 4D CT images using tumor motion patterns from seven lung cancer patients across 13 treatment fractions, with a simulated 5.5 cm{sup 3} spherical lesion. Normal lung tissue image quality was quantified by comparing simulated and ground truth images in terms of overall mean square error (MSE) intensity difference, threshold-based lung volume error, and fractional false positive/false negative rates. Results

  13. CT-verified intracranial calcifications and contrast enhancement in acute disseminated encephalomyelitis: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Ipsen, P. [Department of Neuroradiology, Aarhus University Hospital (Denmark)

    1998-08-01

    Acute disseminated encephalomyelitis (ADEM) is a demyelinating disease which follows viral infection or vaccination. We report the CT findings in a 13-year-old boy with ADEM after infection with Epstein-Barr virus. After 11 days, the patient developed intracranial calcifications in addition to demyelinating lesions. This is a rare finding in ADEM. (orig.) With 4 figs., 15 refs.

  14. CT-verified intracranial calcifications and contrast enhancement in acute disseminated encephalomyelitis: a case report

    International Nuclear Information System (INIS)

    Ipsen, P.

    1998-01-01

    Acute disseminated encephalomyelitis (ADEM) is a demyelinating disease which follows viral infection or vaccination. We report the CT findings in a 13-year-old boy with ADEM after infection with Epstein-Barr virus. After 11 days, the patient developed intracranial calcifications in addition to demyelinating lesions. This is a rare finding in ADEM. (orig.)

  15. Interaction of CtBP with adenovirus E1A suppresses immortalization of primary epithelial cells and enhances virus replication during productive infection

    Energy Technology Data Exchange (ETDEWEB)

    Subramanian, T.; Zhao, Ling-jun; Chinnadurai, G., E-mail: chinnag@slu.edu

    2013-09-01

    Adenovirus E1A induces cell proliferation, oncogenic transformation and promotes viral replication through interaction with p300/CBP, TRRAP/p400 multi-protein complex and the retinoblastoma (pRb) family proteins through distinct domains in the E1A N-terminal region. The C-terminal region of E1A suppresses E1A/Ras co-transformation and interacts with FOXK1/K2, DYRK1A/1B/HAN11 and CtBP1/2 (CtBP) protein complexes. To specifically dissect the role of CtBP interaction with E1A, we engineered a mutation (DL→AS) within the CtBP-binding motif, PLDLS, and investigated the effect of the mutation on immortalization and Ras cooperative transformation of primary cells and viral replication. Our results suggest that CtBP–E1A interaction suppresses immortalization and Ras co-operative transformation of primary rodent epithelial cells without significantly influencing the tumorigenic activities of transformed cells in immunodeficient and immunocompetent animals. During productive infection, CtBP–E1A interaction enhances viral replication in human cells. Between the two CtBP family proteins, CtBP2 appears to restrict viral replication more than CtBP1 in human cells. - Highlights: • Adenovirus E1A C-terminal region suppresses E1A/Ras co-transformation. • This E1A region binds with FOXK, DYRK1/HAN11 and CtBP cellular protein complexes. • We found that E1A–CtBP interaction suppresses immortalization and transformation. • The interaction enhances viral replication in human cells.

  16. Impact of PET/CT system, reconstruction protocol, data analysis method, and repositioning on PET/CT precision: An experimental evaluation using an oncology and brain phantom.

    Science.gov (United States)

    Mansor, Syahir; Pfaehler, Elisabeth; Heijtel, Dennis; Lodge, Martin A; Boellaard, Ronald; Yaqub, Maqsood

    2017-12-01

    In longitudinal oncological and brain PET/CT studies, it is important to understand the repeatability of quantitative PET metrics in order to assess change in tracer uptake. The present studies were performed in order to assess precision as function of PET/CT system, reconstruction protocol, analysis method, scan duration (or image noise), and repositioning in the field of view. Multiple (repeated) scans have been performed using a NEMA image quality (IQ) phantom and a 3D Hoffman brain phantom filled with 18 F solutions on two systems. Studies were performed with and without randomly (PET/CT, especially in the case of smaller spheres (PET metrics depends on the combination of reconstruction protocol, data analysis methods and scan duration (scan statistics). Moreover, precision was also affected by phantom repositioning but its impact depended on the data analysis method in combination with the reconstructed voxel size (tissue fraction effect). This study suggests that for oncological PET studies the use of SUV peak may be preferred over SUV max because SUV peak is less sensitive to patient repositioning/tumor sampling. © 2017 The Authors. Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

  17. Dual-energy MDCT: Comparison of pulmonary artery enhancement on dedicated CT pulmonary angiography, routine and low contrast volume studies

    Energy Technology Data Exchange (ETDEWEB)

    Godoy, Myrna C.B., E-mail: migbarco@gmail.com [New York University Langone Medical Center, Department of Radiology, New York, NY (United States); University of Texas M.D. Anderson Cancer Center, Department of Diagnostic Radiology, Houston, TX (United States); Heller, Samantha L.; Naidich, David P.; Assadourian, Bernard [New York University Langone Medical Center, Department of Radiology, New York, NY (United States); Leidecker, Christianne [Siemens Medical Solutions, Malvern, PA (United States); Schmidt, Bernhard [Siemens Healthcare, Forchheim (Germany); Vlahos, Ioannis [New York University Langone Medical Center, Department of Radiology, New York, NY (United States); St. George' s Hospital NHS Trust, London (United Kingdom)

    2011-08-15

    Purpose: The aim of this study was (a) to compare arterial enhancement in simultaneously acquired high- and low-kilovoltage images; and (b) to determine whether low tube-voltage imaging would permit PE evaluation on routine chest CT studies or CTPA studies performed with a low volume of contrast media. Materials and methods: We compared 20 CTPA studies (CTPA group), 20 routine thoracic CT studies (RT group) and 10 CTPA studies performed with reduced volume of contrast media (RC group). HU values were measured in all groups at 80 kVp and 140 kVp images in multiple pulmonary arterial segments bilaterally. The diagnostic quality of the central and peripheral vascular enhancement and the image noise were evaluated at both energies using a five-point scale. Results: For all patients, the mean CT attenuation values were greater at 80 kVp than 140 kVp images (p < 0.001). At 80 kVp, CTPA group attenuation values were greater than RT group (p = 0.03) with a similar trend at 140 kVp (p = 0.08). At both 140 kVp and 80 kVp, CTPA group attenuation values were greater than RC group (p = 0.02 and p = 0.03, respectively). Qualitative analysis showed that at 140 kVp CTPA studies had better global image quality scores than RT (p = 0.003) and RC (p = 0.001) groups. However, at 80 kVp, there was no significant difference of global image quality between CTPA and the other groups (p = 0.4 and p = 0.5, respectively). Although measurable image noise was greater at 80 kVp than 140 kVp (p < 0.001), qualitative analysis revealed lower image noise at 80 kVp images. Conclusion: DECT at 80 kVp increases arterial enhancement in both CTPA and routine studies. For routine studies this results in central and peripheral enhancement quality equivalent to that of CTPA studies. Low tube-voltage imaging allows marked contrast volume reduction for CTPA. In selected cases, satisfactory lower radiation dose CT might be achievable using lower kVp imaging alone.

  18. Interaction of CtBP with adenovirus E1A suppresses immortalization of primary epithelial cells and enhances virus replication during productive infection.

    Science.gov (United States)

    Subramanian, T; Zhao, Ling-Jun; Chinnadurai, G

    2013-09-01

    Adenovirus E1A induces cell proliferation, oncogenic transformation and promotes viral replication through interaction with p300/CBP, TRRAP/p400 multi-protein complex and the retinoblastoma (pRb) family proteins through distinct domains in the E1A N-terminal region. The C-terminal region of E1A suppresses E1A/Ras co-transformation and interacts with FOXK1/K2, DYRK1A/1B/HAN11 and CtBP1/2 (CtBP) protein complexes. To specifically dissect the role of CtBP interaction with E1A, we engineered a mutation (DL→AS) within the CtBP-binding motif, PLDLS, and investigated the effect of the mutation on immortalization and Ras cooperative transformation of primary cells and viral replication. Our results suggest that CtBP-E1A interaction suppresses immortalization and Ras co-operative transformation of primary rodent epithelial cells without significantly influencing the tumorigenic activities of transformed cells in immunodeficient and immunocompetent animals. During productive infection, CtBP-E1A interaction enhances viral replication in human cells. Between the two CtBP family proteins, CtBP2 appears to restrict viral replication more than CtBP1 in human cells. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Dynamic contrast enhanced CT measurement of blood flow during interstitial laser photocoagulation: comparison with an Arrhenius damage model

    International Nuclear Information System (INIS)

    Purdie, T.J.; Lee, T.J.; Iizuka, M.; Sherar, M.D.

    2000-01-01

    One effect of heating during interstitial laser photocoagulation (ILP) is to directly destroy the tumour vasculature resulting in a loss of viable blood supply. Therefore, blood flow measured during and after treatment can be a useful indicator of tissue thermal damage. In this study, the effect of ILP treatment on rabbit thigh tumours was investigated by measuring blood flow changes using dynamic contrast enhanced computed tomography (CT). The CT measured changes in blood flow of treated tumour tissue were fitted to an Arrhenius model assuming first order rate kinetics. Our results show that changes in blood flow of tumour tissue distant from surrounding normal tissue are well described by an Arrhenius model. By contrast, the temperature profile of tumour tissue adjacent to normal tissue must be modified to account for heat dissipation by the latter. Finally, the Arrhenius parameters derived in the study are similar to those derived by heating tumour tissue to a lower temperature (<47 deg. C) than the current study. In conclusion, CT can be used to monitor blood flow changes during ILP and these measurements are related to the thermal damage predicted by the Arrhenius model. (author)

  20. Non-small cell lung cancer: evaluation of the relationship between fibrosis and washout feature at dynamic contrast enhanced CT

    International Nuclear Information System (INIS)

    Ye Xiaodan; Yuan Zheng; Ye Jianding; Li Huimin; Zhu Yuzhao; Zhang Shunmin; Liu Shiyuan; Xiao Xiangsheng

    2010-01-01

    Objective: To correlate dynamic parameters at contrast enhanced CT and interstitial fibrosis grade of' non-small cell lung cancer (NSCLC). Methods: Twenty-nine patients with NSCLC were evaluated by multi-slice CT. Images were obtained before and at 20, 30, 45, 60, 75, 90, 120, 180, 300, 540, 720, 900 and 1200 s after the injection of contrast media, which was administered at a rate of 4 ml/s for a total of 420 mg I/kg body weight. Washout parameters were calculated. Lung cancer specimens were stained with hematoxylin-eosin stain and collagen and elastic double stain. Spearman test was made to analyze correlation between dynamic parameters and interstitial fibrosis grade of tumor. Results: Twenty- nine NSCLC demonstrated washout at 20 min 12.1 (0.32-58.0) HU, washout ratio at 20 minutes 15.3% (0.3%-39.2%), slope of washout at 20 minutes 0.0152%/s (0.0007%/s-0.0561%/s). Interstitial fibrosis of 29 lesions was graded as grade Ⅰ (10), grade Ⅱ (14) and grade Ⅲ (5). There were significant correlation between washout at 20 min (r=-0.402, P<0.05), washout ratio at 20 min (r= -0.372, P<0.05), slope of washout ratio (r=-0.459, P<0.05) and interstitial fibrosis grade in tumors. Conclusion: NSCLC washout features at dynamic multi-detector CT correlates with interstitial fibrosis in the tumor. (authors)

  1. Hepatic entropy and uniformity: additional parameters that can potentially increase the effectiveness of contrast enhancement during abdominal CT

    International Nuclear Information System (INIS)

    Ganeshan, B.; Miles, K.A.; Young, R.C.D.; Chatwin, C.R.

    2007-01-01

    Aim: To determine how hepatic entropy and uniformity of computed tomography (CT) images of the liver change after the administration of contrast material and to assess whether these additional parameters are more sensitive to tumour-related changes in the liver than measurements of hepatic attenuation or perfusion. Materials and methods: Hepatic attenuation, entropy, uniformity, and perfusion were measured using multi-phase CT following resection of colorectal cancer. Based on conventional CT and fluorodeoxyglucose positron emission tomography, 12 patients were classified as having no evidence of malignancy, eight with extra-hepatic tumours only, and eight with metastatic liver disease. Results: Hepatic attenuation and entropy increased after CM administration whereas uniformity decreased. Unlike hepatic attenuation, entropy and uniformity changed maximally in the arterial phase. No significant differences in hepatic perfusion or attenuation were found between patient groups, whereas arterial-phase entropy was lower (p = 0.034) and arterial-phase uniformity was higher (p = 0.034) in apparently disease-free areas of liver in patients with hepatic metastases compared with those with no metastases. Conclusion: Temporal changes in hepatic entropy and uniformity differ from those for hepatic attenuation. By reflecting the distribution of hepatic enhancement, these additional parameters are more sensitive to tumour-related changes in the liver than measurements of hepatic attenuation or perfusion

  2. Mass-forming intrahepatic cholangiocarcinoma: Enhancement patterns in the arterial phase of dynamic hepatic CT - Correlation with clinicopathological findings

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Nobuhiro; Asayama, Yoshiki; Nishie, Akihiro; Ishigami, Kousei; Ushijima, Yasuhiro; Okamoto, Daisuke; Moirta, Koichiro; Honda, Hiroshi [Kyushu University, Department of Clinical Radiology, Graduate School of Medical Sciences, Higashi-ku, Fukuoka (Japan); Takayama, Yukihisa [Kyushu University, Department of Radiology Informatics and Network, Graduate School of Medical Sciences, Higashi-ku, Fukuoka (Japan); Shirabe, Ken [Kyushu University, Department of Surgery and Science, Graduate School of Medical Sciences, Higashi-ku, Fukuoka (Japan); Aishima, Shinichi [Saga University Hospital, Department of Pathology and Microbiology, Faculty of Medicine, Saga City, Saga (Japan); Wang, Huanlin; Oda, Yoshinao [Kyushu University, Department of Anatomic Pathology, Graduate School of Medical Sciences, Higashi-ku, Fukuoka (Japan)

    2017-02-15

    To evaluate the relationship between the enhancement pattern of intrahepatic cholangiocarcinomas (ICCs) in the hepatic arterial phase (HAP) of dynamic hepatic CT and the clinicopathological findings with special reference to the perihilar type and the peripheral type. Forty-seven patients with pathologically proven ICCs were enrolled. Based on the enhancement pattern in the HAP, the lesions were classified into three groups: a hypovascular group (n=13), rim-enhancement group (n=18), and hypervascular group (n=16). The clinicopathological findings were compared among the three groups. Perihilar-type ICCs were significantly more frequently observed in the hypovascular group than in the rim-enhancement and hypervascular groups (p=0.006 and p <0.001, respectively). Lymphatic invasion, perineural invasion, and biliary invasion were significantly more frequent in the hypovascular group than the rim- enhancement group (p=0.001, p=0.025 and p=0.029, respectively) or hypervascular group (p <0.001, p <0.001 and p=0.025, respectively). Patients with hypovascular lesions showed significantly poorer disease-free survival than patients with rim-enhancing or hypervascular lesions (p=0.001 and p=0.001, respectively). Hypovascularity was an independent preoperative prognostic factor for disease-free survival (p<0.001). Hypovascular ICCs in the HAP tend to be of perihilar type and to have more malignant potential than other ICCs. (orig.)

  3. A study of plaque vascularization and inflammation using quantitative contrast-enhanced US and PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Hjelmgren, Ola, E-mail: ola.hjelmgren@wlab.gu.se [Institute of Medicine, Sahlgrenska Academy at the University of Gothenburg, Department of Molecular and Clinical Medicine, Clinical Physiology, Gothenburg (Sweden); Sahlgrenska University Hospital, Department of Clinical Physiology, Gothenburg (Sweden); Johansson, Lars, E-mail: lars.johansson@radiol.uu.se [Uppsala University, Department of Radiology, Uppsala (Sweden); Prahl, Ulrica, E-mail: ulrica-prahl-gullberg@wlab.gu.se [Institute of Medicine, Sahlgrenska Academy at the University of Gothenburg, Department of Molecular and Clinical Medicine, Clinical Physiology, Gothenburg (Sweden); Schmidt, Caroline, E-mail: caroline.schmidt@wlab.gu.se [Institute of Medicine, Sahlgrenska Academy at the University of Gothenburg, Department of Molecular and Clinical Medicine, Clinical Physiology, Gothenburg (Sweden); Fredén-Lindqvist, Johan, E-mail: johan.freden-lindqvist@vgregion.se [Sahlgrenska University Hospital, Department of Clinical Physiology, Gothenburg (Sweden); Bergström, Göran M.L., E-mail: goran.bergstrom@hjl.gu.se [Institute of Medicine, Sahlgrenska Academy at the University of Gothenburg, Department of Molecular and Clinical Medicine, Clinical Physiology, Gothenburg (Sweden); Sahlgrenska University Hospital, Department of Clinical Physiology, Gothenburg (Sweden)

    2014-07-15

    Background: Contrast-enhanced ultrasound (CEUS) is an in vivo methodology to quantify carotid plaque vascularization. Increased metabolism in plaques, measured as FDG uptake in PET/CT examination, has been associated with markers of inflammation in histological samples. In this study, we tested the association between FDG uptake and vascularization measured by CEUS to assess whether CEUS can be used as an in vivo marker of plaque vulnerability. Methods: After informed consent, subjects aged >60 years with carotid plaque height exceeding 2.5 mm were recruited. CEUS was performed and analyzed using earlier described protocol and software, Contrast Quantification Program, which calculates the fraction of the plaque being contrast positive (CQP value). PET/CT examination was performed within 3 months of CEUS (median time 7 days). PET/CT images were acquired 90 min after FDG injection (2.7 MBq/kg). FDG uptake was measured as tissue background index (TBI), calculated using Spearman's rho as mean standard uptake value (SUV) of the plaque divided by mean SUV in the jugular vein (mean of 7 measuring points). Local ethics committee approved the study. Results: We recruited 13 subjects (5 women) with a mean age of 71 years, 6 had a history of stroke or TIA, 1 had a history of ipsilateral stroke. CQP values showed a significant, positive correlation with TBI of carotid plaques, r = 0.67, p < 0.02. Conclusions: Plaque vascularization measured by CEUS correlates positively with FDG uptake measured by PET/CT in humans. This indicates an association between vascularization and inflammation and/or hypoxia, supporting the use of CEUS as a non-invasive method to detect plaque vulnerability.

  4. A study of plaque vascularization and inflammation using quantitative contrast-enhanced US and PET/CT

    International Nuclear Information System (INIS)

    Hjelmgren, Ola; Johansson, Lars; Prahl, Ulrica; Schmidt, Caroline; Fredén-Lindqvist, Johan; Bergström, Göran M.L.

    2014-01-01

    Background: Contrast-enhanced ultrasound (CEUS) is an in vivo methodology to quantify carotid plaque vascularization. Increased metabolism in plaques, measured as FDG uptake in PET/CT examination, has been associated with markers of inflammation in histological samples. In this study, we tested the association between FDG uptake and vascularization measured by CEUS to assess whether CEUS can be used as an in vivo marker of plaque vulnerability. Methods: After informed consent, subjects aged >60 years with carotid plaque height exceeding 2.5 mm were recruited. CEUS was performed and analyzed using earlier described protocol and software, Contrast Quantification Program, which calculates the fraction of the plaque being contrast positive (CQP value). PET/CT examination was performed within 3 months of CEUS (median time 7 days). PET/CT images were acquired 90 min after FDG injection (2.7 MBq/kg). FDG uptake was measured as tissue background index (TBI), calculated using Spearman's rho as mean standard uptake value (SUV) of the plaque divided by mean SUV in the jugular vein (mean of 7 measuring points). Local ethics committee approved the study. Results: We recruited 13 subjects (5 women) with a mean age of 71 years, 6 had a history of stroke or TIA, 1 had a history of ipsilateral stroke. CQP values showed a significant, positive correlation with TBI of carotid plaques, r = 0.67, p < 0.02. Conclusions: Plaque vascularization measured by CEUS correlates positively with FDG uptake measured by PET/CT in humans. This indicates an association between vascularization and inflammation and/or hypoxia, supporting the use of CEUS as a non-invasive method to detect plaque vulnerability

  5. Appropriate xenon-inhalation time in xenon-enhanced CT using the end-tidal gas-sampling method

    Energy Technology Data Exchange (ETDEWEB)

    Asada, Hideo; Furuhata, Shigeru; Onozuka, Satoshi; Uchida, Koichi; Fujii, Koji; Suga, Sadao; Kawase, Takeshi; Toya, Shigeo; Shiga, Hayao

    1988-12-01

    For the end-tidal gas-sampling method of xenon-enhanced CT (Xe-CT), the respective functional images of K, lambda, and the regional cerebral blood flow (rCBF) were studied and compared using the data at 7-, 10-, 15- and 25-minute inhalations. The most appropriate inhalation time of xenon gas was evaluated in 14 clinical cases. An end-tidal xenon curve which represents the arterial xenon concentration was monitored with a xenon analyzer; the xenon concentration was gradually increased to a level of 50% by using a xenon inhalator with a closed circuit to prevent the overestimation of the xenon concentration sampled from the mask. Serial CT scans were taken over a period of 25 minutes of inhalation. The functional images of K, lambda, and rCBF were calculated for serial CT scans for 7, 10, 15 and 25 minutes using Fick's equation. Those various images and absolute values were then compared. The rCBF value of a 15-minute inhalation was approximately 15% greater than that of 25 minutes, while the values of K, lambda, rCBF from a 15-minute inhalation were significantly correlated to those from 25 minutes. The regression line made it possible to estimate 25-minute inhalation values from those of 15 minutes. In imaging, the rCBF mapping of the 15-minute inhalation was found to be more reliable than that of 25 minutes. This study suggests that the minimal time of xenon inhalation is 15 minutes for the end-tidal gas-sampling method. A longer inhalation may be necessary for the estimation of rCBF in the low-flow area, such as the white matter or the pathological region.

  6. The added value of {sup 68}Ga-DOTA-TATE-PET to contrast-enhanced CT for primary site detection in CUP of neuroendocrine origin

    Energy Technology Data Exchange (ETDEWEB)

    Kazmierczak, Philipp M. [Klinikum der Universitaet Muenchen, Institut fuer Klinische Radiologie, Muenchen (Germany); Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Muenchen (Germany); Rominger, Axel; Wenter, Vera [Ludwig-Maximilians-University Hospital Munich, Department of Nuclear Medicine, Muenchen (Germany); Spitzweg, Christine; Auernhammer, Christoph [Ludwig-Maximilians-University Hospital Munich, Department of Internal Medicine II, Muenchen (Germany); Angele, Martin K. [Ludwig-Maximilians-University Hospital Munich, Department of General, Visceral, Transplantation, Vascular and Thoracic Surgery, Muenchen (Germany); Rist, Carsten; Cyran, Clemens C. [Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Muenchen (Germany)

    2017-04-15

    To quantify the additional value of {sup 68}Ga-DOTA-TATE PET/CT in comparison with contrast-enhanced CT alone for primary tumour detection in neuroendocrine cancer of unknown primary (CUP-NET). In total, 38 consecutive patients (27 men, 11 women; mean age 62 years) with histologically proven CUP-NET who underwent a contrast-enhanced {sup 68}Ga-DOTA-TATE PET/CT scan for primary tumour detection and staging between 2010 and 2014 were included in this IRB-approved retrospective study. Two blinded readers independently analysed the contrast-enhanced CT and {sup 68}Ga-DOTA-TATE PET datasets separately and noted from which modality they suspected a primary tumour. Consensus was reached if the results were divergent. Postoperative histopathology (24 patients) and follow-up {sup 68}Ga-DOTA-TATE PET/CT imaging (14 patients) served as the reference standards and statistical measures of diagnostic accuracy were calculated accordingly. The majority of confirmed primary tumours were located in the abdomen (ileum in 19 patients, pancreas in 12, lung in 2, small pelvis in 1). High interobserver agreement was noted regarding the suspected primary tumour site (Cohen's k 0.90, p < 0.001). {sup 68}Ga-DOTA-TATE PET demonstrated a significantly higher sensitivity (94 % vs. 63 %, p = 0.005) and a significantly higher accuracy (87 % vs. 68 %, p = 0.003) than contrast-enhanced CT. Ga-DOTA-TATE PET/CT compared with contrast-enhanced CT alone provides an improvement in sensitivity of 50 % and an improvement in accuracy of 30 % in primary tumour detection in CUP-NET. (orig.)

  7. Opportunities for new CT contrast agents to maximize the diagnostic potential of emerging spectral CT technologies.

    Science.gov (United States)

    Yeh, Benjamin M; FitzGerald, Paul F; Edic, Peter M; Lambert, Jack W; Colborn, Robert E; Marino, Michael E; Evans, Paul M; Roberts, Jeannette C; Wang, Zhen J; Wong, Margaret J; Bonitatibus, Peter J

    2017-04-01

    The introduction of spectral CT imaging in the form of fast clinical dual-energy CT enabled contrast material to be differentiated from other radiodense materials, improved lesion detection in contrast-enhanced scans, and changed the way that existing iodine and barium contrast materials are used in clinical practice. More profoundly, spectral CT can differentiate between individual contrast materials that have different reporter elements such that high-resolution CT imaging of multiple contrast agents can be obtained in a single pass of the CT scanner. These spectral CT capabilities would be even more impactful with the development of contrast materials designed to complement the existing clinical iodine- and barium-based agents. New biocompatible high-atomic number contrast materials with different biodistribution and X-ray attenuation properties than existing agents will expand the diagnostic power of spectral CT imaging without penalties in radiation dose or scan time. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. FDG Dose Extravasations in PET/CT: Frequency and Impact on SUV Measurements

    International Nuclear Information System (INIS)

    Osman, Medhat M.; Muzaffar, Razi; Altinyay, M. Erkan; Teymouri, Cyrus

    2011-01-01

    Objectives: Positron emission tomography (PET)/CT with 18F-FDG has proven to be effective in detecting and assessing various types of cancers. However, due to cancer and/or its therapy, intravenous (IV) FDG injection may be problematic resulting in dose extravasations. In the most frequently used field of view (FOV), arms-up, and base of skull to upper thigh [limited whole body (LWB)], the injection site may not be routinely imaged. The purpose of this study was to evaluate the frequency of dose extravasations in FDG PET and the potential impact on standard uptake value (SUV) measurements. Methods: True whole body FDG PET/CT scans (including all extremities) of 400 patients were retrospectively reviewed. A log recorded cases of IV dose extravasations. When possible, SUVs were measured in two frequently used reference locations: mediastinum and liver. The SUVs were obtained in the same patients who had studies with and without FDG extravasations within an average of 3 months without interval therapy. Results: Of the 400 scans, 42 (10.5%) had extravasations on the maximum intensity projections images. In scans with or without dose infiltration, FDG injection site was at or distal to the antecubital fossa in 97% of studies. Of those 42 cases, dose infiltration was within the LWB FOV in 29/42 (69%) and outside in the remaining 13/42 (31%). Of those 42 patients, 5 had repeat PET studies with no interval therapy. For those 5 patients, liver maximum SUV was 11.7% less in patients with infiltration than those without (2.22 ± 0.54 vs. 2.48 ± 0.6). Mediastinum SUVmax was 9.3% less in patients with infiltration than those without (1.72 ± 0.54 vs. 1.88 ± 0.49). Conclusion: We conclude dose extravasations were commonly encountered (10.5%) in PET/CT. However, it is underreported by at least 31% due to omitting injection site from the FOV. When present, extravasations may lead to underestimation of SUVmax. Therefore, it should not only be avoided but also reported in order to

  9. FDG dose extravasations in PET/CT: frequency and impact on SUV measurements

    Directory of Open Access Journals (Sweden)

    Medhat M Osman

    2011-11-01

    Full Text Available Objectives: PET/CT with 18F-FDG has proven to be effective in detecting and assessing various types of cancers. However, due to cancer and/or its therapy, intravenous (IV FDG injection may be problematic resulting in dose extravasations. In the most frequently used field of view (FOV, arms-up and base of skull to upper-thigh (limited Whole Body (LWB, the injection site may not be routinely imaged. The purpose of this study was to evaluate the frequency of dose extravasations in FDG PET and the potential impact on SUV measurements.Methods: True Whole Body (TWB FDG-PET/CT scans (including all extremities of 400 patients were retrospectively reviewed. A log recorded cases of IV dose extravasations. When possible, SUVs were measured in two frequently used reference locations: mediastinum and liver. The SUVs were obtained in the same patients who had studies with and without FDG extravasations within an average of 3 months without interval therapy.Results: Of the 400 scans, 42 (10.5% had extravasations on the maximum intensity projections (MIP images. In scans with or without dose infiltration, FDG injection site was at or distal to the antecubital fossa in 97% of studies. Of those 42 cases, dose infiltration was within the LWB FOV in 29/42 (69% and outside in the remaining 13/42 (31%. Of those 42 patients, 5 had repeat PET studies with no interval therapy. For those 5 patients, liver maximum SUV was 11.7% less in patients with infiltration than those without (2.22 ± 0.54 vs. 2.48 ± 0.6. Mediastinum SUVmax was 9.3% less in patients with infiltration than those without (1.72 ± 0.54 vs. 1.88 ± 0.49.Conclusion: We conclude dose extravasations were commonly encountered (10.5% in PET/CT. However, it is underreported by at least 31% due to omitting injection site from the FOV. When present, extravasations may lead to underestimation of SUVmax. Therefore, it should not only be avoided but also reported in order to avoid false interpretations of the exam.

  10. Impact of multidetector CT-angiography on the emergency management of severe hemoptysis

    Energy Technology Data Exchange (ETDEWEB)

    Chalumeau-Lemoine, Ludivine [Service de Pneumologie et Réanimation, Hôpital Tenon, HUEP, APHP, 4 rue de la Chine, 75020 Paris (France); Khalil, Antoine, E-mail: antoine_khalil@yahoo.fr [Service de Radiologie, Hôpital Tenon, HUEP, APHP, 4 rue de la Chine, 75020 Paris (France); Pathological Angiogenesis and Vessel Normalization, Center for Interdisciplinary Research in Biology, CNRS UMR 7241/INSERM U1050, Collège de France, Paris (France); Prigent, Hélène [Service de Pneumologie et Réanimation, Hôpital Tenon, HUEP, APHP, 4 rue de la Chine, 75020 Paris (France); Carette, Marie-France [Service de Radiologie, Hôpital Tenon, HUEP, APHP, 4 rue de la Chine, 75020 Paris (France); Université Pierre et Marie Curie, Paris VI (France); Fartoukh, Muriel [Service de Pneumologie et Réanimation, Hôpital Tenon, HUEP, APHP, 4 rue de la Chine, 75020 Paris (France); Université Pierre et Marie Curie, Paris VI (France); Parrot, Antoine [Service de Pneumologie et Réanimation, Hôpital Tenon, HUEP, APHP, 4 rue de la Chine, 75020 Paris (France)

    2013-11-01

    Background: Multidetector CT-angiography (MDCTA) is commonly used in patients with severe haemoptysis requiring admission to intensive care unit. However, the impact of MDCTA on the management of severe haemoptysis in emergency setting is poorly evaluated. Methods: We prospectively compared data provided by clinical bedside evaluation (clinical examination, chest-X-ray and fiberoptic bronchoscopy) to MDCTA data in terms of lateralization, location of the bleeding site, etiology as well as impact on the treatment choice. Results: Over a 13-month period, 87 patients (men n = 58, median age = 61 years, median haemoptysis expectorated volume = 180 mL) were included. Etiology was mainly (67%) bronchiectasis, tuberculosis sequelae and tumor. MDCTA and clinical bedside evaluation were equally effective in determining lateralization (87.4% and 93.1%, respectively, p = 0.23) and location (85% and 82.7%, respectively, p = 0.82) of the bleeding site. MDCTA was significantly more accurate than the clinical bedside strategy in determining the haemoptysis cause (86% and 70%, respectively, p = 0.007). Moreover, MDCTA suggested the involvement of systemic arteries as bleeding mechanism in 92% of cases, leading to the modification of the treatment initially considered after bedside evaluation in 21.8% of patients. Conclusion: MDCTA provides useful information for the management of patients with severe haemoptysis, especially in the treatment choice. Thus, in the absence of emergency fiberoptic bronchoscopy (FOB) requirement for airways management, MDCTA should be the first-line procedure performed in emergency clinical setting.

  11. Impact of multidetector CT-angiography on the emergency management of severe hemoptysis

    International Nuclear Information System (INIS)

    Chalumeau-Lemoine, Ludivine; Khalil, Antoine; Prigent, Hélène; Carette, Marie-France; Fartoukh, Muriel; Parrot, Antoine

    2013-01-01

    Background: Multidetector CT-angiography (MDCTA) is commonly used in patients with severe haemoptysis requiring admission to intensive care unit. However, the impact of MDCTA on the management of severe haemoptysis in emergency setting is poorly evaluated. Methods: We prospectively compared data provided by clinical bedside evaluation (clinical examination, chest-X-ray and fiberoptic bronchoscopy) to MDCTA data in terms of lateralization, location of the bleeding site, etiology as well as impact on the treatment choice. Results: Over a 13-month period, 87 patients (men n = 58, median age = 61 years, median haemoptysis expectorated volume = 180 mL) were included. Etiology was mainly (67%) bronchiectasis, tuberculosis sequelae and tumor. MDCTA and clinical bedside evaluation were equally effective in determining lateralization (87.4% and 93.1%, respectively, p = 0.23) and location (85% and 82.7%, respectively, p = 0.82) of the bleeding site. MDCTA was significantly more accurate than the clinical bedside strategy in determining the haemoptysis cause (86% and 70%, respectively, p = 0.007). Moreover, MDCTA suggested the involvement of systemic arteries as bleeding mechanism in 92% of cases, leading to the modification of the treatment initially considered after bedside evaluation in 21.8% of patients. Conclusion: MDCTA provides useful information for the management of patients with severe haemoptysis, especially in the treatment choice. Thus, in the absence of emergency fiberoptic bronchoscopy (FOB) requirement for airways management, MDCTA should be the first-line procedure performed in emergency clinical setting

  12. Transient gyriform brightness on non-contrast enhanced computed tomography (CT) brain scan of seven infants

    International Nuclear Information System (INIS)

    Close, P.J.; Carty, H.M.

    1991-01-01

    Spontaneous gyriform brightness seen on CT scan is an unusual finding unless associated with arteriovenous malformations (AVM). There are sporadic case reports in the literature of its occurrence in association with herpex simplex virus encephalitis (HSVE), purulent meningitis, following chemotherapy for leukaemia, in a child with chronic renal failure, and in a child with folic acid deficiency. We present a series of seven cases exhibiting this phenomenon, none of whom have AVMs, who have been scanned at this hospital in the first 2 1/2 years following the installation of a CT scanner. Four of the cases had congenital heart disease requiring corrective surgery or cardiac catheterisation. The other three had probable meningo-encephalitis. In all cases the gyriform brightness followed an ischaemic insult to the child's brain. We hypothesise that this phenomenon is an ischaemic response in the immature brain and that its occurrence is not so rare as the literature may suggest. (orig.)

  13. TH-EF-207A-04: A Dynamic Contrast Enhanced Cone Beam CT Technique for Evaluation of Renal Functions

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z; Shi, J; Yang, Y [University of Miami School of Medicine, Miami, FL (United States)

    2016-06-15

    Purpose: To develop a simple but robust method for the early detection and evaluation of renal functions using dynamic contrast enhanced cone beam CT technique. Methods: Experiments were performed on an integrated imaging and radiation research platform developed by our lab. Animals (n=3) were anesthetized with 20uL Ketamine/Xylazine cocktail, and then received 200uL injection of iodinated contrast agent Iopamidol via tail vein. Cone beam CT was acquired following contrast injection once per minute and up to 25 minutes. The cone beam CT was reconstructed with a dimension of 300×300×800 voxels of 130×130×130um voxel resolution. The middle kidney slices in the transvers and coronal planes were selected for image analysis. A double exponential function was used to fit the contrast enhanced signal intensity versus the time after contrast injection. Both pixel-based and region of interest (ROI)-based curve fitting were performed. Four parameters obtained from the curve fitting, namely the amplitude and flow constant for both contrast wash in and wash out phases, were investigated for further analysis. Results: Robust curve fitting was demonstrated for both pixel based (with R{sup 2}>0.8 for >85% pixels within the kidney contour) and ROI based (R{sup 2}>0.9 for all regions) analysis. Three different functional regions: renal pelvis, medulla and cortex, were clearly differentiated in the functional parameter map in the pixel based analysis. ROI based analysis showed the half-life T1/2 for contrast wash in and wash out phases were 0.98±0.15 and 17.04±7.16, 0.63±0.07 and 17.88±4.51, and 1.48±0.40 and 10.79±3.88 minutes for the renal pelvis, medulla and cortex, respectively. Conclusion: A robust method based on dynamic contrast enhanced cone beam CT and double exponential curve fitting has been developed to analyze the renal functions for different functional regions. Future study will be performed to investigate the sensitivity of this technique in the detection

  14. Potential impact of 68Ga-PSMA-11 PET/CT on prostate cancer definitive radiation therapy planning.

    Science.gov (United States)

    Calais, Jérémie; Kishan, Amar U; Cao, Minsong; Fendler, Wolfgang P; Eiber, Matthias; Herrmann, Ken; Ceci, Francesco; Reiter, Robert E; Matthew, Rettig B; Hegde, John V; Shaverdian, Narek; King, Christopher R; Steinberg, Michael L; Czernin, Johannes; Nickols, Nicholas G

    2018-04-13

    Background: Standard-of-care imaging for initial staging of prostate cancer (PCa) underestimates disease burden. Prostate specific membrane antigen (PSMA) positron emission tomography/ computed tomography (PET/CT) detects PCa metastasis with superior accuracy with potential impact definitive radiation therapy (RT) planning for non-metastatic PCa. Objectives: i) To determine how often definitive PCa RT planning based on standard target volumes cover 68 Ga-PSMA-11 PET/CT defined disease, and ii) To assess the potential impact of 68 Ga-PSMA-11 PET/CT on definitive PCa RT planning. Patients and Methods: This is a post-hoc analysis of an intention to treat population of 73 patients with localized PCa without prior local therapy who underwent 68 Ga-PSMA PET/CT for initial staging as part of an Investigational New Drug trial. 11/73 were intermediate-risk (15%), 33/73 were high-risk (45%), 22/73 were very high risk (30%), and 7/73 were N1 (9.5%). Clinical target volumes (CTVs) that included the prostate, seminal vesicles, and pelvic lymph nodes (LNs) using Radiation Therapy Oncology Group (RTOG) consensus guidelines were contoured on the CT portion of the PET/CT by a radiation oncologist blinded to the PET findings. 68 Ga-PSMA-11 PET/CT images were analyzed by a nuclear medicine physician. PSMA-positive lesions not covered by planning volumes based on the CTVs were considered to have a major potential impact on treatment planning. Results: All patients had PSMA-positive primary prostate lesion(s). 25/73 (34%) and 7/73 (9.5%) had PSMA-positive pelvic nodal and distant metastases, respectively. The sites of nodal metastases in decreasing order of frequency were external iliac (20.5%), common iliac (13.5%), internal iliac (12.5%) obturator (12.5%), perirectal (4%), abdominal (4%), upper-diaphragm (4%), and presacral (1.5%). The median size of the nodal lesions was 6 mm (range 4-24 mm). RT planning based on the CTVs covered 69/73 (94.5%) of primary disease and 20/25 (80%) of

  15. Impact of enhanced flow on the flow system and wastewater ...

    African Journals Online (AJOL)

    In this study, we estimated the impact of enhanced flow on shallow wetlands that receive major effluent discharge from an adjoining metropolitan city. The local people use the shallow wetlands for pisciculture. Beginning in 1998, the population of the city began to rise and the amount of effluent discharge increased.

  16. Impact of Business Education in Enhancing Sales Volumes of Retail ...

    African Journals Online (AJOL)

    This study investigated the impact of business education in enhancing sales volume of retail business in Ohaozara local Government Area of Ebonyi State. Ninety (90) respondents formed the population of study. The instrument of data collection was a well structured and pretested questionnaire. Two research questions ...

  17. Comparison of Dynamic Contrast-Enhanced MRI and PET/CT in the Evaluation of Laryngeal Cancer After Inadequate CT Results

    International Nuclear Information System (INIS)

    Citil, Serdal; Dogan, Serap; Atilgan, Hasan Ikbal; Menzilcioglu, Mehmet Sait; Sahin, Tuna; Abdulrezzak, Ummuhan; Duymus, Mahmut; Ozturk, Mustafa

    2015-01-01

    To investigate the diagnostic value of dynamic magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT) for laryngeal cancers after inadequate CT results. The study comprised 45 patients investigated for primary laryngeal cancer or recurrence-residue in which CT was considered inadequate. A mass was found in 20 patients. Dynamic MRI and PET/CT were compared for diagnosis of mass, lymph node involvement, recurrence and residue. The dynamic curves formed in dynamic MRI were investigated for diagnostic contributions. The sensitivity and specificity of the dynamic MRI, for supraglottic, glottic and subglottic location, was 100%, 80%, and 92%; 100%, 85%, and 100%, respectively. In PET/CT the sensitivity and specificity were 100% for all of those localizations. For lymph node involvement, the sensitivity of dynamic MRI and PET/CT was 100%, the specificity was 100% and 93%, respectively. For recurrence-residue, the sensitivity and specificity of dynamic MRI were 86% and 67%, respectively, with 100% sensitivity and specificity in PET/CT. The sensitivity of type A curve for detection of malignancy was 40%, and specificity was 100%. When type A and B curves were included, the sensitivity was 100%. For patients investigated for laryngeal cancer in which CT is considered inadequate, dynamic MRI or PET/CT is useful

  18. Comparison of Dynamic Contrast-Enhanced MRI and PET/CT in the Evaluation of Laryngeal Cancer After Inadequate CT Results.

    Science.gov (United States)

    Citil, Serdal; Dogan, Serap; Atilgan, Hasan Ikbal; Menzilcioglu, Mehmet Sait; Sahin, Tuna; Abdulrezzak, Ummuhan; Duymus, Mahmut; Ozturk, Mustafa

    2015-01-01

    To investigate the diagnostic value of dynamic magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT) for laryngeal cancers after inadequate CT results. The study comprised 45 patients investigated for primary laryngeal cancer or recurrence-residue in which CT was considered inadequate. A mass was found in 20 patients. Dynamic MRI and PET/CT were compared for diagnosis of mass, lymph node involvement, recurrence and residue. The dynamic curves formed in dynamic MRI were investigated for diagnostic contributions. The sensitivity and specificity of the dynamic MRI, for supraglottic, glottic and subglottic location, was 100%, 80%, and 92%; 100%, 85%, and 100%, respectively. In PET/CT the sensitivity and specificity were 100% for all of those localizations. For lymph node involvement, the sensitivity of dynamic MRI and PET/CT was 100%, the specificity was 100% and 93%, respectively. For recurrence-residue, the sensitivity and specificity of dynamic MRI were 86% and 67%, respectively, with 100% sensitivity and specificity in PET/CT. The sensitivity of type A curve for detection of malignancy was 40%, and specificity was 100%. When type A and B curves were included, the sensitivity was 100%. For patients investigated for laryngeal cancer in which CT is considered inadequate, dynamic MRI or PET/CT is useful.

  19. Respiratory gated PET/CT of the liver: A novel method and its impact on the detection of colorectal liver metastases

    International Nuclear Information System (INIS)

    Schulz, Anselm; Godt, Johannes Clemens; Dormagen, Johann Baptist; Holtedahl, Jon Erik; Bogsrud, Trond Velde; Labori, Knut Jørgen; Kløw, Nils-Einar; Bach-Gansmo, Tore

    2015-01-01

    Highlights: • Combined PET/CT and respiratory gated PET/CT improved sensitivity significantly. • Respiratory gated PET/CT had greatest impact on detection of small CRLM <10 mm. • Our results were comparable to earlier reported more complex and expensive methods. • The method used is inexpensive and requires only limited additional imaging time. - Abstract: Purpose: To evaluate the diagnostic performance of a new method for respiratory gated positron emission tomography (rgPET/CT) for colorectal liver metastases (CRLM), secondly, to assess its additional value to standard PET/CT (PET/CT). Materials and methods: Forty-three patients scheduled for resection of suspected CRLM were prospectively included from September 2011 to January 2013. None of the patients had previously undergone treatment for their CRLM. All patients underwent PET/CT and rgPET/CT in the same session. For rgPET/CT an in-house developed electronic circuit was used which displayed a color-coded countdown for the patient. The patients held their breath according to the countdown and only the data from the inspiration breath-hold period was used for image reconstruction. Two independent and blinded readers evaluated both PET/CT and rgPET/CT separately. The reference standard was histopathological confirmation for 73 out of 131 CRLM and follow-up otherwise. Results: Reference standard identified 131 CRLM in 39/43 patients. Nine patients accounted for 25 mucinous CRLM. The overall per-lesion sensitivity for detection of CRLM was for PET/CT 60.0%, for rgPET/CT 63.1%, and for standard + rgPET/CT 67.7%, respectively. Standard + rgPET/CT was overall significantly more sensitive for CRLM compared to PET/CT (p = 0.002) and rgPET/CT (p = 0.031). The overall positive predictive value (PPV) for detection of CRLM was for PET/CT 97.5%, for rgPET/CT 95.3%, and for standard + rgPET/CT 93.6%, respectively. Conclusion: Combination of PET/CT and rgPET/CT improved the sensitivity significantly for CRLM. However

  20. Respiratory gated PET/CT of the liver: A novel method and its impact on the detection of colorectal liver metastases

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, Anselm, E-mail: anselm.schulz@gmail.com [Department of Radiology and Nuclear Medicine, Oslo University Hospital, Postboks Pb 4956 Nydalen, 0424 Oslo (Norway); Institute of Clinical Medicine, University of Oslo, P.O. Box 1171 Blindern, 0318 Oslo (Norway); Godt, Johannes Clemens, E-mail: UXGODJ@ous-hf.no [Department of Radiology and Nuclear Medicine, Oslo University Hospital, Postboks Pb 4956 Nydalen, 0424 Oslo (Norway); Institute of Clinical Medicine, University of Oslo, P.O. Box 1171 Blindern, 0318 Oslo (Norway); Dormagen, Johann Baptist, E-mail: UXJORM@ous-hf.no [Department of Radiology and Nuclear Medicine, Oslo University Hospital, Postboks Pb 4956 Nydalen, 0424 Oslo (Norway); Holtedahl, Jon Erik, E-mail: JONHOL@ous-hf.no [The Intervention Centre, Oslo University Hospital, Postboks 4950 Nydalen, 0424 Oslo (Norway); Bogsrud, Trond Velde, E-mail: tvbog@aol.com [Department of Radiology and Nuclear Medicine, Oslo University Hospital, Postboks Pb 4956 Nydalen, 0424 Oslo (Norway); Department of Nuclear Medicine and PET-Center, Aarhus University Hospital, Norrebrogade 44, DK-8000 Aarhus C (Denmark); Labori, Knut Jørgen, E-mail: uxknab@ous-hf.no [Department of Hepato-Pancreato-Biliary Surgery, Oslo University Hospital, Postboks 4950 Nydalen, 0424 Oslo (Norway); Kløw, Nils-Einar, E-mail: NILKLO@ous-hf.no [Department of Radiology and Nuclear Medicine, Oslo University Hospital, Postboks Pb 4956 Nydalen, 0424 Oslo (Norway); Institute of Clinical Medicine, University of Oslo, P.O. Box 1171 Blindern, 0318 Oslo (Norway); Bach-Gansmo, Tore, E-mail: bat@ous-hf.no [Department of Radiology and Nuclear Medicine, Oslo University Hospital, Postboks Pb 4956 Nydalen, 0424 Oslo (Norway)

    2015-08-15

    Highlights: • Combined PET/CT and respiratory gated PET/CT improved sensitivity significantly. • Respiratory gated PET/CT had greatest impact on detection of small CRLM <10 mm. • Our results were comparable to earlier reported more complex and expensive methods. • The method used is inexpensive and requires only limited additional imaging time. - Abstract: Purpose: To evaluate the diagnostic performance of a new method for respiratory gated positron emission tomography (rgPET/CT) for colorectal liver metastases (CRLM), secondly, to assess its additional value to standard PET/CT (PET/CT). Materials and methods: Forty-three patients scheduled for resection of suspected CRLM were prospectively included from September 2011 to January 2013. None of the patients had previously undergone treatment for their CRLM. All patients underwent PET/CT and rgPET/CT in the same session. For rgPET/CT an in-house developed electronic circuit was used which displayed a color-coded countdown for the patient. The patients held their breath according to the countdown and only the data from the inspiration breath-hold period was used for image reconstruction. Two independent and blinded readers evaluated both PET/CT and rgPET/CT separately. The reference standard was histopathological confirmation for 73 out of 131 CRLM and follow-up otherwise. Results: Reference standard identified 131 CRLM in 39/43 patients. Nine patients accounted for 25 mucinous CRLM. The overall per-lesion sensitivity for detection of CRLM was for PET/CT 60.0%, for rgPET/CT 63.1%, and for standard + rgPET/CT 67.7%, respectively. Standard + rgPET/CT was overall significantly more sensitive for CRLM compared to PET/CT (p = 0.002) and rgPET/CT (p = 0.031). The overall positive predictive value (PPV) for detection of CRLM was for PET/CT 97.5%, for rgPET/CT 95.3%, and for standard + rgPET/CT 93.6%, respectively. Conclusion: Combination of PET/CT and rgPET/CT improved the sensitivity significantly for CRLM. However

  1. Dynamic contrast-enhanced micro-CT on mice with mammary carcinoma for the assessment of antiangiogenic therapy response

    Energy Technology Data Exchange (ETDEWEB)

    Eisa, Fabian [University of Erlangen-Nuremberg, Institute of Medical Physics, Erlangen (Germany); University of Erlangen-Nuremberg, Graduate School in Advanced Optical Technologies (SAOT), Erlangen (Germany); Brauweiler, Robert; Hupfer, Martin; Nowak, Tristan; Kalender, Willi A. [University of Erlangen-Nuremberg, Institute of Medical Physics, Erlangen (Germany); Lotz, Laura; Hoffmann, Inge; Dittrich, Ralf; Beckmann, Matthias W. [University of Erlangen-Nuremberg, OB/GYN, University Hospital Erlangen, Erlangen (Germany); Wachter, David [University Hospital Erlangen, Institute of Pathology, Erlangen (Germany); Jost, Gregor; Pietsch, Hubertus [Bayer Pharma AG, Berlin (Germany)

    2012-04-15

    To evaluate the potential of in vivo dynamic contrast-enhanced micro-computed tomography (DCE micro-CT) for the assessment of antiangiogenic drug therapy response of mice with mammary carcinoma. 20 female mice with implanted MCF7 tumours were split into control group and therapy group treated with a known effective antiangiogenic drug. All mice underwent DCE micro-CT for the 3D analysis of functional parameters (relative blood volume [rBV], vascular permeability [K], area under the time-enhancement curve [AUC]) and morphology. All parameters were determined for total, peripheral and central tumour volumes of interest (VOIs). Immunohistochemistry was performed to characterise tumour vascularisation. 3D dose distributions were determined. The mean AUCs were significantly lower in therapy with P values of 0.012, 0.007 and 0.023 for total, peripheral and central tumour VOIs. K and rBV showed significant differences for the peripheral (P{sub per}{sup K} = 0.032, P{sub per}{sup rBV} = 0.029), but not for the total and central tumour VOIs (P{sub total}{sup K} = 0.108, P{sub central}{sup K} = 0.246, P{sub total}{sup rBV} = 0.093, P{sub central}{sup rBV} = 0.136). Mean tumour volume was significantly smaller in therapy (P{sub in} {sub vivo} = 0.001, P{sub ex} {sub vivo} = 0.005). Histology revealed greater vascularisation in the controls and central tumour necrosis. Doses ranged from 150 to 300 mGy. This study indicates the great potential of DCE micro-CT for early in vivo assessment of antiangiogenic drug therapy response. (orig.)

  2. Deep Learning with Convolutional Neural Network for Differentiation of Liver Masses at Dynamic Contrast-enhanced CT: A Preliminary Study.

    Science.gov (United States)

    Yasaka, Koichiro; Akai, Hiroyuki; Abe, Osamu; Kiryu, Shigeru

    2018-03-01

    Purpose To investigate diagnostic performance by using a deep learning method with a convolutional neural network (CNN) for the differentiation of liver masses at dynamic contrast agent-enhanced computed tomography (CT). Materials and Methods This clinical retrospective study used CT image sets of liver masses over three phases (noncontrast-agent enhanced, arterial, and delayed). Masses were diagnosed according to five categories (category A, classic hepatocellular carcinomas [HCCs]; category B, malignant liver tumors other than classic and early HCCs; category C, indeterminate masses or mass-like lesions [including early HCCs and dysplastic nodules] and rare benign liver masses other than hemangiomas and cysts; category D, hemangiomas; and category E, cysts). Supervised training was performed by using 55 536 image sets obtained in 2013 (from 460 patients, 1068 sets were obtained and they were augmented by a factor of 52 [rotated, parallel-shifted, strongly enlarged, and noise-added images were generated from the original images]). The CNN was composed of six convolutional, three maximum pooling, and three fully connected layers. The CNN was tested with 100 liver mass image sets obtained in 2016 (74 men and 26 women; mean age, 66.4 years ± 10.6 [standard deviation]; mean mass size, 26.9 mm ± 25.9; 21, nine, 35, 20, and 15 liver masses for categories A, B, C, D, and E, respectively). Training and testing were performed five times. Accuracy for categorizing liver masses with CNN model and the area under receiver operating characteristic curve for differentiating categories A-B versus categories C-E were calculated. Results Median accuracy of differential diagnosis of liver masses for test data were 0.84. Median area under the receiver operating characteristic curve for differentiating categories A-B from C-E was 0.92. Conclusion Deep learning with CNN showed high diagnostic performance in differentiation of liver masses at dynamic CT. © RSNA, 2017 Online

  3. The study of two methods for high pressure injection in CT enhancement to display the aortic dissecting aneurysm

    International Nuclear Information System (INIS)

    Wang Yang; Zhu Bin; Zhang Zhen

    2008-01-01

    Objective: To discuss the consequences of two different methods of high pressure injection in CT contrast enhancement to display the aortic dissecting aneurysm. Methods: 100 patients underwent Lightspeed 16 MS CT with contrast enhancement of Stellant D high pressure injector (Medrad), injecting speed of 4.0 mL/s and 80 ml dosage of contrast medium. All patients were divided into A and B groups with 50 in each. The single high pressure injection was applied to A group without isotonic Na chloride flush. B group underwent the same high pressure injection and followed by isotonic Na chloride flush. The method of evaluation was carried out by double blind observation. Results: A group revealed radiologic artifact up to 40 cases with positive rate of 80%. B group demonstrated the same kind of radiologic artifact in 26 cases with positive rate of 52%. Conclusions: Using normal saline (sodium chloride solution)flush after high pressure injection of contrast medium during MSCT angiography is obviously better to demonstrate the internal structures of treatvessels. (authors)

  4. Impact of the planning CT scan time on the reflection of the lung tumor motion

    International Nuclear Information System (INIS)

    Kim, Su San; Choi, Eun Kyung; Yi, Byong Yong; Ha, Sung Whan

    2004-01-01

    To evaluate the reflection of tumor motion according to the planning CT scan time. A model of N-shape, which moved along the longitudinal axis during the ventilation caused by a mechanical ventilator, was produced. The model was scanned by planning CT, while setting the relative CT scan time (T; CT scan time/ventilatory period) to 0.33, 0.50, 0.67, 0.75, 1.00, 1.33 T, and 1.53 T. In addition, three patients with non-small cell lung cancer who received stereotactic radiosurgery in the Department of Radiation Oncology, Asan Medical Center from 03/19/2002 to 05/21/2002 were scanned. Slow (IQ Premier, Picker, scan time 2.0 seconds per slice) and fast CT scans (Light Speed, GE Medical System, with a scan time of 0.8 second per slice) were performed for each patient. The magnitude of reflected movement of the N-shaped model was evaluated by measuring the transverse length, which reflected the movement of the declined bar of the model at each slice. For patients' scans, all CT data sets were registered using a stereotactic body frame scale with the gross tumor volumes delineated in one CT image set. The volume and three-dimensional diameter of the gross tumor volume were measured and analyzed between the slow and fast CT scans. The reflection degree of longitudinal movement of the model increased in proportion to the relative CT scan times below 1.00 T, but remained constant above 1.00 T. Assuming the mean value of scanned transverse lengths with CT scan time 1.00 T to be 100%, CT scans with scan times of 0.33, 0.50, 0.67, and 0.75 T missed the tumor motion by 30, 27, 20, and 7.0% respectively. Slow (scan time 2.0 sec) and Fast (scan time 0.8 sec) CT scans of three patients with longitudinal movement of 3, 5, and 10 mm measured by fluoroscopy revealed the increases in the diameter along the longitudinal axis increased by 6.3, 17, and 23% in the slow CT scans. As the relative CT scan time increased, the reflection of the respiratory tumor movement on planning CT also

  5. Effect of different saline chaser volumes and flow rates on intravascular contrast enhancement in CT using a circulation phantom

    International Nuclear Information System (INIS)

    Behrendt, Florian F.; Bruners, Philipp; Keil, Sebastian; Plumhans, Cedric; Mahnken, Andreas H.; Das, Marco; Ackermann, Diana; Guenther, Rolf W.; Muehlenbruch, Georg

    2010-01-01

    Purpose: To evaluate the influence of different saline chaser volumes and different saline chaser flow rates on the intravascular contrast enhancement in MDCT. Materials and methods: In a physiological flow phantom contrast medium (120 ml, 300 mgI/ml, Ultravist 300) was administered at a flow rate of 6 ml/s followed by different saline chaser volumes (0, 30, 60 and 90 ml) at the same injection rate or followed by a 30-ml saline chaser at different injection rates (2, 4, 6 and 8 ml/s). Serial CT-scans at a level covering the pulmonary artery, the ascending and the descending aorta replica were obtained. Time-enhancement curves were computed and both pulmonary and aortic peak enhancement and peak time were determined. Results: Compared to contrast medium injection without a saline chaser the pushing with a saline chaser (30, 60, and 90 ml) resulted in a statistically significant increased pulmonary peak enhancement (all p = 0.008) and prolonged peak time (p = 0.032, p = 0.024 and p = 0.008, respectively). Highest aortic peak enhancement values were detected for a saline chaser volume of 30 ml. A saline chaser flow rate of 8 ml/s resulted in the highest pulmonary peak enhancement values compared to flow rates of 2, 4 and 6 ml/s (all p = 0.008). Aortic peak enhancement showed the highest values for a flow rate of 6 ml/s. Conclusion: A saline chaser volume of 30 ml and an injection rate of 6 ml/s are sufficient to best improve vascular contrast enhancement in the pulmonary artery and the aorta in MDCT.

  6. Dynamic contrast-enhanced CT in advanced lung cancer after chemotherapy with/within radiation therapy: Can it predict treatment responsiveness of the tumor?

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Mi Ri; Whang, Sung Ho; Park, Chul Hwan; Kim, Sang Jin; Kim, Tae Hoon [Dept. of Radiology and Research Institute of Radiological Science, Yonsei University Health System, Seoul (Korea, Republic of)

    2013-08-15

    To evaluate the contrast enhancement patterns of lung cancer after chemotherapy using a dynamic contrast-enhanced (DCE) CT and to determine whether the enhancement patterns of tumors at early stages of treatment can predict treatment responses. Forty-two patients with advanced lung cancers underwent DCE-CT and follow-up CT after chemotherapy. We evaluated peak and net enhancement (PE and NE, respectively) and time-density curves (TDCs) (type A, B, C, and D) on DCE-CT images. Treatment responses were evaluated using revised Response Evaluation Criteria in Solid Tumor criteria. NE and PE values were significantly higher in the progressive disease (PD) groups than in the stable disease (SD) or partial response (PR) groups (p < 0.05). Types B, C, and D on TDCs were observed mostly in the PR and SD groups (96.0%), whereas type A was most frequent in the SD and PD groups (97.2%), which were significantly different in terms of PE and NE. Contrast enhancement pattern regarding the response of treatment on DCE-CT images could be helpful in predicting treatment response of advanced lung cancer after treatment.

  7. Clinical impact of PET/CT imaging after adjuvant therapy in patients with oral cavity squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Huan-Chun [Chang Gung Memorial Hospital and Chang Gung University, Department of Nuclear Medicine and Molecular Imaging Center, Taoyuan (China); Kang, Chung-Jan; Huang, Shiang-Fu; Liao, Chun-Ta [Chang Gung Memorial Hospital and Chang Gung University, Department of Otorhinolaryngology, Head and Neck Surgery, Taoyuan (China); Wang, Hung-Ming [Chang Gung Memorial Hospital and Chang Gung University, Department of Medical Oncology, Taoyuan (China); Lin, Chien-Yu [Chang Gung Memorial Hospital and Chang Gung University, Department of Radiation Oncology, Taoyuan (China); Lee, Li-Yu [Chang Gung Memorial Hospital and Chang Gung University, Department of Pathology, Taoyuan (China); Yen, Tzu-Chen [Chang Gung Memorial Hospital and Chang Gung University, Department of Nuclear Medicine and Molecular Imaging Center, Taoyuan (China); Chang Gung Memorial Hospital at Linkou, Department of Nuclear Medicine, Taoyuan (China)

    2017-09-15

    This single-center retrospective study of prospectively collected data was aimed at comparing the clinical outcomes of positron emission tomography/computed tomography (PET/CT) for patients with oral cavity squamous cell carcinoma (OSCC) with symptomatic recurrences identified by PET/CT imaging following adjuvant therapy (Group A) versus those of cases with asymptomatic recurrences diagnosed through periodic post-adjuvant therapy PET/CT surveillance (Group B). We also sought to establish the priority of salvage therapy in the two study groups. We identified 111 patients with advanced resected OSCC who developed recurrences following adjuvant therapy (51 in Group A and 60 in Group B). Histopathology served as the gold standard for recurrent lesions. The impact of post-adjuvant therapy PET/CT surveillance was examined with Kaplan-Meier curves and Cox proportional hazards regression models. The 2-year DSS and OS rates were marginally or significantly higher in Group B than in Group A (P = 0.073 and P = 0.025, respectively). Time-dependent ROC curve analysis demonstrated that the optimal cutoff values for time to positive PET/CT findings in relation to OS were 12 months for Group A and 9 months for Group B, respectively. Independent risk factors identified in multivariate analyses were used to devise two prognostic scoring systems for 2-year DSS and OS in each study group (all P < 0.001). Scheduled periodic PET/CT surveillance is a valuable tool for early detection of recurrent lesion(s) in asymptomatic OSCC patients who bear risk factors for disease recurrence. The presence of clinical symptoms and a short time to positive PET/CT findings were adverse prognostic factors for clinical outcome in patients with advanced OSCC. The priority of salvage therapy is discussed in each patient subgroup according to the devised prognostic scoring systems. (orig.)

  8. Adrenergic pathway activation enhances brown adipose tissue metabolism: A [18 F]FDG PET/CT study in mice

    International Nuclear Information System (INIS)

    Mirbolooki, M. Reza; Upadhyay, Sanjeev Kumar; Constantinescu, Cristian C.; Pan, Min-Liang; Mukherjee, Jogeshwar

    2014-01-01

    Objective: Pharmacologic approaches to study brown adipocyte activation in vivo with a potential of being translational to humans are desired. The aim of this study was to examine pre- and postsynaptic targeting of adrenergic system for enhancing brown adipose tissue (BAT) metabolism quantifiable by [ 18 F]fluoro-2-deoxyglucose ([ 18 F]FDG) positron emission tomography (PET)/computed tomography (CT) in mice. Methods: A β 3 -adrenoreceptor selective agonist (CL 316243), an adenylyl cyclase enzyme activator (forskolin) and a potent blocker of presynaptic norepinephrine transporter (atomoxetine), were injected through the tail vein of Swiss Webster mice 30 minutes before intravenous (iv) administration of [ 18 F]FDG. The mice were placed on the PET/CT bed for 30 min PET acquisition followed by 10 min CT acquisition for attenuation correction and anatomical delineation of PET images. Results: Activated interscapular (IBAT), cervical, periaortic and intercostal BAT were observed in 3-dimentional analysis of [ 18 F]FDG PET images. CL 316243 increased the total [ 18 F]FDG standard uptake value (SUV) of IBAT 5-fold greater compared to that in placebo-treated mice. It also increased the [ 18 F]FDG SUV of white adipose tissue (2.4-fold), and muscle (2.7-fold), as compared to the control. There was no significant difference in heart, brain, spleen and liver uptakes between groups. Forskolin increased [ 18 F]FDG SUV of IBAT 1.9-fold greater than that in placebo-treated mice. It also increased the [ 18 F]FDG SUV of white adipose tissue (2.2-fold) and heart (5.4-fold) compared to control. There was no significant difference in muscle, brain, spleen, and liver uptakes between groups. Atomoxetine increased [ 18 F]FDG SUV of IBAT 1.7-fold greater than that in placebo-treated mice. There were no significant differences in all other organs compared to placebo-treated mice except liver (1.6 fold increase). A positive correlation between SUV levels of IBAT and CT Hounsfield unit (HU

  9. Assessment of ablative margin after radiofrequency ablation for hepatocellular carcinoma; comparison between magnetic resonance imaging with ferucarbotran and enhanced CT with iodized oil deposition

    International Nuclear Information System (INIS)

    Koda, Masahiko; Tokunaga, Shiho; Fujise, Yuki; Kato, Jun; Matono, Tomomitsu; Sugihara, Takaaki; Nagahara, Takakazu; Ueki, Masaru; Murawaki, Yoshikazu; Kakite, Suguru; Yamashita, Eijiro

    2012-01-01

    Background and purpose: Our aim was to investigate whether magnetic resonance imaging (MRI) with ferucarbotran administered prior to radiofrequency ablation could accurately assess ablative margin when compared with enhanced computed tomography (CT) with iodized oil marking. Materials and methods: We enrolled 27 patients with 32 hepatocellular carcinomas in which iodized oil deposits were visible throughout the nodule after transcatheter arterial chemoembolization. For these nodules, radiofrequency ablation was performed after ferucarbotran administration. We then performed T2-weighted MRI after 1 week and enhanced CT after 1 month. T2-weighted MRI demonstrated the ablative margin as a low-intensity rim. We classified the margin into three grades; margin (+): high-intensity area with a continuous low-intensity rim; margin zero: high-intensity area with a discontinuous low-intensity rim; and margin (−): high-intensity area extending beyond the low-intensity rim. Results: In 28 (86%) of 32 nodules, there was agreement between MRI and CT. The overall agreement between for the two modalities in the assessment of ablative margin was good (κ = 0.759, 95% confidence interval: 0.480–1.000, p < 0.001). In four nodules, ablative margins on MRI were underestimated by one grade compared with CT. Conclusion: MRI using ferucarbotran is less invasive and allows earlier assessment than CT. The MRI technique performed similarly to enhanced CT with iodized oil marking in evaluating the ablative margin after radiofrequency ablation.

  10. Dynamic multidetector CT and non-contrast-enhanced MR for right adrenal vein imaging: comparison with catheter venography in adrenal venous sampling

    Energy Technology Data Exchange (ETDEWEB)

    Ota, Hideki; Seiji, Kazumasa; Kawabata, Masahiro; Satani, Nozomi; Matsuura, Tomonori; Tominaga, Junya; Takase, Kei [Tohoku University Hospital, Department of Diagnostic Radiology, Sendai (Japan); Omata, Kei; Ono, Yoshikiyo; Iwakura, Yoshitsugu; Morimoto, Ryo; Kudo, Masataka; Satoh, Fumitoshi; Ito, Sadayoshi [Tohoku University Hospital, Division of Nephrology, Endocrinology and Vascular Medicine, Sendai (Japan)

    2016-03-15

    To evaluate visualization of the right adrenal vein (RAV) with multidetector CT and non-contrast-enhanced MR imaging in patients with primary aldosteronism. A total of 125 patients (67 men) scheduled for adrenal venous sampling (AVS) were included. Dynamic 64-detector-row CT and balanced steady-state free precession-based non-contrast-enhanced 3-T MR imaging were performed. RAV visualization based on a four-point score was documented. Both anatomical location and variation on cross-sectional imaging were evaluated, and the findings were compared with catheter venography as the gold standard. The RAV was visualized in 93.2 % by CT and 84.8 % by MR imaging (p = 0.02). Positive predictive values of RAV visualization were 100 % for CT and 95.2 % for MR imaging. Imaging score was significantly higher in CT than MR imaging (p < 0.01). The RAV formed a common trunk with an accessory hepatic vein in 16 % of patients. The RAV orifice level on cross-sectional imaging was concordant with catheter venography within the range of 1/3 vertebral height in >70 % of subjects. Success rate of AVS was 99.2 %. Dynamic CT is a reliable way to map the RAV prior to AVS. Non-contrast-enhanced MR imaging is an alternative when there is a risk of complication from contrast media or radiation exposure. (orig.)

  11. Do TSH, FT3, and FT4 Impact BAT Visualization of Clinical FDG-PET/CT Images?

    Directory of Open Access Journals (Sweden)

    Ryuichi Nishii

    2018-01-01

    Full Text Available Objective. We retrospectively analyzed activated BAT visualization on FDG-PET/CT in patients with various conditions and TH levels to clarify the relationships between visualization of BAT on FDG-PET/CT and the effect of TH. Methods. Patients who underwent clinical FDG-PET/CT were reviewed and we categorized patients into 5 groups: (i thyroid hormone withdrawal (THW group; (ii recombinant human thyrotropin (rhTSH group; (iii hypothyroidism group; (iv hyperthyroidism group; and (v BAT group. A total of sixty-two FDG-PET/CT imaging studies in fifty-nine patients were performed. To compare each group, gender; age; body weight; serum TSH, FT3, and FT4 levels; and outside temperature were evaluated. Results. No significant visualization of BAT was noted in any of the images in the THW, rhTSH, hypothyroidism, and hyperthyroidism groups. All patients in the BAT group were in a euthyroid state. When the BAT-negative and BAT-positive patient groups were compared, it was noted that the minimum and maximum temperature on the day of the PET study and maximum temperature of the one day before the PET study were significantly lower in BAT-positive group than in all those of other groups. Conclusions. Elevated TSH condition before RIT, hyperthyroidism, or hypothyroidism did not significantly impact BAT visualization of clinical FDG-PET/CT images.

  12. Do TSH, FT3, and FT4 Impact BAT Visualization of Clinical FDG-PET/CT Images?

    Science.gov (United States)

    Nishii, Ryuichi; Nagamachi, Shigeki; Mizutani, Youichi; Terada, Tamasa; Kiyohara, Syogo; Wakamatsu, Hideyuki; Fujita, Seigo; Higashi, Tatsuya; Yoshinaga, Keiichiro; Saga, Tsuneo; Hirai, Toshinori

    2018-01-01

    We retrospectively analyzed activated BAT visualization on FDG-PET/CT in patients with various conditions and TH levels to clarify the relationships between visualization of BAT on FDG-PET/CT and the effect of TH. Patients who underwent clinical FDG-PET/CT were reviewed and we categorized patients into 5 groups: (i) thyroid hormone withdrawal (THW) group; (ii) recombinant human thyrotropin (rhTSH) group; (iii) hypothyroidism group; (iv) hyperthyroidism group; and (v) BAT group. A total of sixty-two FDG-PET/CT imaging studies in fifty-nine patients were performed. To compare each group, gender; age; body weight; serum TSH, FT3, and FT4 levels; and outside temperature were evaluated. No significant visualization of BAT was noted in any of the images in the THW, rhTSH, hypothyroidism, and hyperthyroidism groups. All patients in the BAT group were in a euthyroid state. When the BAT-negative and BAT-positive patient groups were compared, it was noted that the minimum and maximum temperature on the day of the PET study and maximum temperature of the one day before the PET study were significantly lower in BAT-positive group than in all those of other groups. Elevated TSH condition before RIT, hyperthyroidism, or hypothyroidism did not significantly impact BAT visualization of clinical FDG-PET/CT images.

  13. Diagnostic Accuracy of Ultrasound, Contrast-enhanced CT, and Conventional MRI for Differentiating Leiomyoma From Leiomyosarcoma.

    Science.gov (United States)

    Gaetke-Udager, Kara; McLean, Karen; Sciallis, Andrew P; Alves, Timothy; Maturen, Katherine E; Mervak, Benjamin M; Moore, Andreea G; Wasnik, Ashish P; Erba, Jake; Davenport, Matthew S

    2016-10-01

    This study aimed to determine whether uterine leiomyoma can be distinguished from uterine leiomyosarcoma on ultrasound (US), computed tomography (CT), and/or magnetic resonance imaging (MRI) witho