Prognostic values of ADCmean and SUVmax of the primary tumour in cervical cancer patients treated with definitive chemoradiotherapy.

We analysed the correlation of 18F-fluorodeoxyglucose uptake into primary tumours using the maximum standardised uptake value (SUVmax) and the mean apparent diffusion coefficient (ADCmean) values in magnetic resonance imaging (MRI) with the clinical and pathological factors in patients with cervical cancer who were treated with concurrent chemoradiotherapy. The patients were stratified according to the primary tumour pre-treatment ADCmean and SUVmax cut-off values. There were significant correlations between the SUVmax of the primary tumour and tumour size, and the treatment response. The correlation between the ADCmean and FIGO stage, tumour size, and the lymph node metastasis was significant. The SUVmax was significantly and inversely correlated with the ADCmean for cervical cancer (r = -0.44, p <.001). In the multivariate analysis, the primary tumour ADCmean, treatment response and the lymph node metastasis emerged as significant independent predictors of both OS and DFS, and of the primary tumour SUVmax for DFS. Tumour size has a borderline significance for OS. High SUVmax and low ADCmean of the primary tumour are important predictive factors for identifying high-risk patients with cervical cancer who are treated with definitive chemoradiotherapy. These results point to a future role for the diffusion-weighted MRI and for 18F-fluorodeoxyglucose positron emission tomography, not only in the staging of cervical cancer but as an aid in the selection of an adjuvant treatment regimen after chemoradiotherapy for individual patients. Impact statement What is already known on this subject? A negative correlation between primary tumour SUVmax derived from positron emission tomography (PET/CT) and ADCmin derived from diffusion weighted magnetic resonance imaging (DW-MRI) in various cancer types and cervical cancer has been demonstrated. However, the prognostic value of primary tumour SUVmax and ADCmean in cervical cancer patients treated with definitive chemoradiotherapy is not well studied yet. What the results of this study add? The patients with high-risk features (larger tumours, extensive stage, lymph node metastasis) had higher primary tumour SUVmax and lower ADCmean values. Primary tumour ADCmean and lymph node metastasis emerged as significant independent predictors of both overall and disease-free survival. This study demonstrated that the functional biomarkers delivered from PET-CT and DW-MRI are important in predicting the treatment outcomes in the squamous cell carcinoma of cervix treated with definitive chemoradiotherapy, where clinical and radiological findings are very important, since these patients are not staged surgically. What are the implications of these findings for clinical practice and/or further research? Based on these findings, there may be a future role of DW-MRI and FDG/PET-CT not only in the staging of cervical cancer but as an aid in the selection of an adjuvant treatment regimen after chemoradiotherapy (ChRT) for individual patients.

Internal comparison standard for abdominal diffusion-weighted imaging.

Background Standards for abdominal diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) measurements, and analysis are required for reproducibility. Purpose To identify optimal internal comparison standards for DWI to normalize the measured ADC for increased accuracy of differentiating malignant and benign abdominal lesions. Material and Methods We retrospectively studied 97 lesions (89 patients; age, 57 ± 13 years) with histopathologically confirmed abdominal disease. Seven normal body parts/contents (normal parenchyma, spleen, kidney, gallbladder bile, paraspinal muscle, spinal cord, and cerebrospinal fluid [CSF]) were assessed as internal references for possible use as comparison standards. Three observers performed ADC measurements. Statistical analyses included interclass correlation coefficients (ICCs), Mann-Whitney and Kruskal-Wallis tests, and coefficient of variation (CV). ROC analyses were performed to assess diagnostic accuracy of lesion ADC and normalized ADC for differentiating lesions. Pathology results were the reference standard. Results Mean and normalized ADCs were significantly lower for malignant lesions than for benign lesions ( P < 0.001). ICC was excellent for all internal references. Gallbladder had the lowest CV. Receiver operating characteristic (ROC) analyses showed that normalized ADCs obtained using normal parenchyma were better than lesion ADCs for differentiating malignant and benign abdominal lesions (area under the curve [AUC], 0.808 and 0.756, respectively). The normalized ADCs obtained using CSF shows higher accuracy than lesion ADCs (0.80 and 0.76, respectively) for differentiating between malignant and benign abdominal lesions. Conclusion The normal parenchyma from a lesion-detected organ can be used as an internal comparison standard for DWI. CSF can be used as a generalizable in plane reference standard.

Predicting tumor recurrence in patients with cervical carcinoma treated with definitive chemoradiotherapy: value of quantitative histogram analysis on diffusion-weighted MR images.

Background Further research is required for evaluating the use of ADC histogram analysis in more advanced stages of cervical cancer treated with definitive chemoradiotherapy (CRT). Purpose To investigate the utility of apparent diffusion coefficient (ADC) histogram derived from diffusion-weighted magnetic resonance images in cervical cancer patients treated with definitive CRT. Material and Methods The clinical and radiological data of 50 patients with histologically proven cervical squamous cell carcinoma treated with definitive CRT were retrospectively analyzed. The impact of clinicopathological factors and ADC histogram parameters on prognostic factors and treatment outcomes was assessed. Results The mean and median ADC values for the cohort were 1.043 ± 0.135 × 10-3 mm2/s and 1.018 × 10-3 mm2/s (range, 0.787-1.443 × 10-3 mm2/s). The mean ADC was significantly lower for patients with advanced stage (≥IIB) or lymph node metastasis compared with patients with stage

Utility of Diffusion-Weighted MRI to Detect Changes in Liver Diffusion in Benign and Malignant Distal Bile Duct Obstruction: The Influence of Choice of b-Values.

PURPOSE: The study sought to evaluate the potential of diffusion-weighted magnetic resonance imaging to detect changes in liver diffusion in benign and malignant distal bile duct obstruction and to investigate the effect of the choice of b-values on apparent diffusion coefficient (ADC). METHODS: Diffusion-weighted imaging was acquired with b-values of 200, 600, 800, and 1000 s/mm2. ADC values were obtained in 4 segments of the liver. The mean ADC values of 16 patients with malignant distal bile duct obstruction, 14 patients with benign distal bile duct obstruction, and a control group of 16 healthy patients were compared. RESULTS: Mean ADC values for 4 liver segments were lower in the malignant obstruction group than in the benign obstruction and control groups using b = 200 s/mm2 (P < .05). Mean ADC values of the left lobe medial and lateral segments were lower in the malignant obstruction group than in the benign obstructive and control groups using b = 600 s/mm2 (P < .05). Mean ADC values of the right lobe posterior segment were lower in the malignant and benign obstruction groups than in the control group using b = 1000 s/mm2 (P < .05). Using b = 800 s/mm2, ADC values of all 4 liver segments in each group were not significantly different (P > .05). There were no correlations between the ADC values of liver segments and liver function tests. CONCLUSION: Measurement of ADC shows good potential for detecting changes in liver diffusion in patients with distal bile duct obstruction. Calculated ADC values were affected by the choice of b-values.

A rarely seen diffuse parenchymal lung disease: diffuse pulmonary meningotheliomatosis.

Pulmonary meningothelial-like nodules (MLNs) are usually detected incidentally during pathologic evaluation of resected pulmonary parenchymal specimens and autopsies. These nodules are generally asymptomatic and most often single. Diffuse pulmonary involvement by MLNs is less frequently described. MLNs are benign lesions and have been associated with neoplastic and non-neoplastic pulmonary conditions and occasionally with extrapulmonary diseases. We report a case of a female patient presenting with multiple and bilateral pulmonary nodules diagnosed with "diffuse pulmonary meningotheliomatosis" by video-assisted thoracoscopic surgery (VATS). Diffuse pulmonary meningotheliomatosis should be included in the differential diagnosis of diffuse bilateral lung nodules in the radiologic studies.

Optimal b value in diffusion-weighted imaging for differentiation of abdominal lesions.

PURPOSE: To explore the optimal b value in diffusion-weighted imaging (DWI) for differentiation of benign and malignant abdominal lesions. MATERIALS AND METHODS: A total of 108 consecutive patients (age 60 ± 12.5 years) with 127 pathologically confirmed diagnoses of abdominal lesions were included. Single-shot echoplanar imaging (SH-EPI) DWI (1.5T) with seven b values and eight apparent diffusion coefficient (ADC) maps were obtained. The lesions were analyzed visually on DWI and ADC maps for benignity/malignity using a 5-point scale and by measuring the ADC values and ADC lesion/normal parenchyma ADC ratio. ROC analysis was used to evaluate the diagnostic accuracy of ADC for differentiating between benign and malignant lesions. Pathology results were the reference standard. RESULTS: Differentiation between malignant and benign lesions using visual scoring was successful at b values of 600 or higher (sensitivities, specificities, and accuracies were 100/93.8/92.5, 84.7/82.6/80.4, and 94.4/89.7/88.1, respectively, for b600, 800, and 1000). The mean ADC values of malignant lesions were significantly lower than those of benign lesions for all b-value combinations except b0 and 50 s/mm(2) (P = 0.032 for b0 and 50 s/mm(2) , P = 0.000 for other b values). The best b-value combination was 0 and 600 s/mm(2) and multiple b2. The lesion/normal parenchymal ADC ratio for b600, b1000, and multiple b2 better distinguished between benign and malignant lesions. CONCLUSION: In DWI, the optimal b value is 600 s/mm(2) ; multiple b values of 600 s/mm(2) and higher are recommended to differentiate between benign and malignant abdominal lesions. The lesion ADC/normal parenchyma ADC ratio is more accurate than using lesion ADC only.

Diffusion-weighted MRI and optimal b-value for characterization of liver lesions.

BACKGROUND: Diffusion-weighted imaging (DWI) is commonly used to distinguish between benign and malignant liver lesions. However, different b-values are recommended. PURPOSE: To determine the most suitable b-value in DWI for differentiation of benign and malignant liver lesions. MATERIAL AND METHODS: A total of 124 lesions in 89 consecutive patients (43 men, 46 women; age, mean ± standard deviation, 58 ± 14 years) with a pathological or radiological diagnosis of malignant or benign focal liver lesions after magnetic resonance imaging (MRI) were included in this study. Routine abdominal MRI and DWI were performed using seven b-values (0, 50, 200, 400, 600, 800, 1000 s/mm(2)). Lesions were analyzed for benignity/malignity using apparent diffusion coefficient (ADC) values with 10 b-value combinations and by measuring the lesion/normal parenchyma ADC ratio. RESULTS: Mean ADC values were significantly different between malignant and benign lesions for all b-value combinations (P=0.000). The best b-value combination was 0 and 800 (Az=0.935). Using lower b-values such as 0 and 50 together with higher b-values ≥ 600 s/mm(2) was beneficial (Az=0.928 and 0.927). Mean ADC values were approximately 13% (1-15%) higher in total when b=0 and b=50 s/mm(2) were included in multiple b-value combinations. CONCLUSION: In DWI, we recommend the use of b-values of 0 and 800 s/mm(2) as two b-values, or b=0, 50, 600, 800, and 1000 s/mm(2) as multiple b-values for distinguishing between benign and malignant liver lesions. Mean ADC value is 13% higher in total by additional use of b=0 and b=50 s/mm(2) in multiple b-value combinations.

Optimization of b value in diffusion-weighted MRI for characterization of benign and malignant gynecological lesions.

PURPOSE: To explore the optimal b value in diffusion-weighted (DW)-MRI for differentiation of benign and malignant gynecological lesions. MATERIALS AND METHODS: Consecutive 58 patients (66 lesions) with pathologically confirmed diagnosis of gynecological disease were included in the study. Routine pelvic MRI sequences were used for defining the lesions and reviewed independently for benignity/ malignity. Single-shot echoplanar imaging (SH-EPI) DW-MRI with eight b values and nine apparent diffusion coefficient (ADC) maps were obtained. The lesions were analyzed qualitatively on DW-MRI for benignity/malignity on a five-point-scale and quantitatively by measurement of apparent diffusion coefficient (ADC) values. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic accuracy of ADC values for differentiating between benign and malignant lesions. Pathology results were the reference standard. RESULTS: Differentiation between benign and malignant gynecological lesions using visual scoring was found to be successful with b values of 600, 800, or 1000 s/mm(2) . The mean ADC values of malignant lesions were significantly lower than those of benign lesions for all b value (P < 0.005). The ADCs with b = 0 and 600, 0 and 1000 s/mm(2) , 0, 600, 800 and 1000 s/mm(2) , and all b values were more effective for distinguishing malignant from benign gynecological lesions (Az = 0.851, 0.847, 0.848, 0.849, respectively). Using ADC with b = 0, 600, 800, and 1000 s/mm(2) , a threshold value of 1.20 × 10(-3) mm(2) /s permitted this distinction with a sensitivity of 83%, a specificity of 81%. CONCLUSION: DW-MRI is an important method, and the optimal b values are between 600 and 1000 s/mm(2) for differentiation between benign and malignant gynecological lesions.

Radiation recall pneumonitis caused by erlotinib after palliative definitive radiotherapy.

BACKGROUND: Radiation recall pneumonitis (RRP) occurs in a previously irradiated field and is triggered by certain cytotoxic drugs, principally chemotherapeutic agents such as erlotinib. Erlotinib is a reversible epidermal growth factor receptor tyrosine kinase inhibitor (TKI) and is an effective second-line treatment for patients with advanced-stage non-squamous-cell lung cancer. Previously, only 2 cases of radiation recall after erlotinib treatment have been reported. Here, we report a case of RRP caused by treatment with erlotinib 4 months after palliative definitive hypofractionated radiation therapy (RT). PATIENT AND METHODS: A 58-year-old male patient with non-small cell lung cancer (adenocarcinoma) was treated with polychemotherapy, palliative RT (30 Gy in 10 fractions), and erlotinib thereafter. RESULTS: Dosimetric analysis obtained from a 3-dimensional conformal RT planning system revealed that the volume of lung receiving at least 20 Gy (V20) was 21.2% and the mean lung dose was 12.7 Gy. These data indicate that systemic administration of a TKI, even after palliative RT, may lead to unexpected toxicity when the radiation field encompasses visceral organs. CONCLUSION: We conclude that the use of a TKI after RT may trigger radiation pneumonitis. Although evidence is limited, we advise clinicians to be cautious of RRP after erlotinib treatment.

Evaluation of malignant and benign renal lesions using diffusion-weighted MRI with multiple b values.

BACKGROUND: Limited data are available regarding the use of diffusion-weighted (DW) magnetic resonance imaging (MRI) with multiple b values for characterization of renal lesions. PURPOSE: To demonstrate and compare the diagnostic performance of DW-MRI with multiple b values for renal lesion characterization. MATERIAL AND METHODS: Sixty-three lesions (36 malignant, 27 benign) in 60 consecutive patients (48 men, 12 women; age 60 ± 12.5 years) with solid/cystic renal lesion diagnosed after MRI were included prospectively. Single-shot echo-planar DW abdominal MRI (1.5T) was obtained using seven b values with eight apparent diffusion coefficient (ADC) maps. Contrast-to-noise ratios (CNRs), signal intensities, lesion ADCs, and lesion/normal parenchyma ADC ratios were analyzed. Receiver-operating characteristic analysis was performed. RESULTS: The mean signal intensities of malignant lesions (at b0, 50, and 200s/mm(2)) were significantly lower than those of benign lesions (P < 0.05). The mean ADC values at all b value combinations of malignant lesions were significantly lower than those of benign lesions (P < 0.000), excluding the ADC value at b50 s/mm(2). ADC with all b values could better distinguish between benign and malignant lesions. A 1.35 × 10(-3) mm(2)/s threshold ADC value permitted this distinction with 85.2% sensitivity and 65.6% specificity. The lesion/normal parenchyma ADC ratio was more effective than the lesion ADC. CONCLUSION: In addition to the ADC value, the signal intensity curve on DW images using multiple b values could be helpful for differentiation of malignant and benign renal lesions.

Multidetector computed tomography diagnosis of ileal and antropyloric gallstone ileus.

Gallstone-induced ileus is a rare complication of cholelithiasis, and gastric outlet obstruction is even rarer. We describe the multidetector computed tomographic diagnosis of small bowel obstruction resulting from a gallstone impacted in the distal ileum and of gastric outlet obstruction from a gallstone impacted in the pyloric antrum (Bouveret syndrome).

Rapamycin therapy for renal, brain, and skin lesions in a tuberous sclerosis patient.

Tuberous sclerosis complex (TSC) is an inherited multisystem disorder; it may involve kidney, brain, skin, lungs, and liver. We report a 37-year-old female TSC patient presenting with skin lesions (angiofibromas, molluscum pendulum). Radiologic examination revealed additional brain and renal lesions consisting of tumors, cysts, and angiomyolipomas. Treatment with rapamycin disclosed improvement in skin lesions. The number and volume of angiofibromas and molluscum pendulum reduced progressively in 6 months. During the ninth month of treatment, magnetic resonance imaging was repeated for renal and brain lesions. Imaging results showed reduction in tumor and angiomyolipoma volumes. Oral rapamycin therapy can improve renal, brain, and skin lesions in TSC disease. Therefore, it may be an alternative therapy for TSC patients.

Joubert syndrome associated with new MRI findings and posterior reversible encephalopathy syndrome.

Joubert syndrome (JS) is an inherited disorder characterized by transient episodic hyperpnea, ataxia, and vermian hypoplasia. Typical imaging findings of JS include hypoplasia or aplasia of the cerebellar vermis, thick and elongated superior cerebellarpeduncles and an abnormally deep interpeduncular fossa with 'molar tooth sign'. We present a case of JS associated with deep cerebral sulci and fissures, polymicrogyria, and additional findings of posterior reversible encephalopathy syndrome associated with renal involvement.

Thorax CT Dose Reduction Based on Patient Features: Effect of Patient Characteristics on Image Quality and Effective Dose.

Computed tomography (CT) radiation dose reduction is vital without compromising image quality. The aim was to determine the effects of patient characteristics on the received radiation dose and image quality in chest CT examinations and to be able to predict dose and image quality prior to scanning. Consecutive 230 patients underwent routine chest CT examinations were included. CT examination and patients input parameters were recorded for each patient. The effect of patients' demographics/anthropometrics on received dose and image quality was investigated by linear regression analysis. All parameters were evaluated using an artificial neural network (ANN). Of all parameters, patient demographics/anthropometrics were found to be 98% effective in calculating dose reduction. Using ANN on 60 new patients was more than 90% accurate for output parameters and 91% for image quality. Patient characteristics have a significant impact on radiation dose and image quality. Dose and image quality can be determined before CT. This will allow setting the most appropriate scanning parameters before the CT scan.

Migrating and herniating hydatid cysts.

OBJECTIVE: To present the prevalence and imaging findings of patients with hydatid disease (HD) showing features of migration or herniation of the hydatid cysts (HCs) and underline the clinical significance of this condition. MATERIALS AND METHODS: Between May 2003 and June 2006, 212 patients with HD were diagnosed by abdomen and/or thorax CT, searched for migrating or herniating HC. Imaging findings of 7 patients (5 women, 2 men with an age range of 19-63 years; mean+/-S.D., 44+/-19 years) with HD showing transdiaphragmatic migration (6 subjects) or femoral herniation (1 subject) were evaluated. Diagnosis of all the patients were established by pathologic examination and migration or herniation was confirmed by surgery in all patients. RESULTS: Liver HD were identified in 169 (79.7%) of 212 patients with HD. Transdiaphragmatic migration of HCs were identified in 6 (3.5%) of the 169 patients with liver HD. In one patient, femoral herniation of the retroperitoneal HC into the proximal anterior thigh was identified. All of these seven patients exhibiting migration or herniation of HCs had active HCs including 'daughter cysts'. Two patients had previous surgery because of liver HD and any supradiaphragmatic lesion was not noted before operation. Findings of migration or herniation were confirmed by surgery. CONCLUSION: Active HCs may show migration or herniation due to pressure difference between the anatomic cavities, and in some of the patients, by contribution of gravity. Previous surgery may be a complementary factor for migration as seen in two of our patients. The possibility of migration or herniation in patients with HD should be considered before surgery.

Neurofibromatosis type 1 association with moyamoya disease.

The neurofibromatoses are genetic disorders of the nervous system that primarily affect the development and growth of neural (nerve) cell tissues. The neurofibromatoses are classified as neurofibromatosis type 1 (NF1) and neurofibromatosis type 2 (NF2). NF1 is the more common type of the neurofibromatoses. The gene responsible for NF1 is located on the chromosome region 17q11.2 and for familial moyamoya disease on chromosome 17q25. This article reports on a 20-year-old female with neurofibromatosis-1 who developed moyamoya syndrome. More extensive reports and further investigations of such families having this combination will certainly provide a better understanding of this link in the near future.

Utility of Diffusion Weighted Magnetic Resonance Imaging with Multiple B Values in Evaluation of Pancreatic Malignant and Benign Lesions and Pancreatitis.

OBJECTIVE: To determine the feasibility of diffusion-weighted imaging in evaluation of pancreatic lesions and in differentiation of benign from malignant lesions. STUDY DESIGN: Descriptive study. PLACE AND DURATION OF STUDY: Baskent University Adana Teaching and Research Center, Adana, Turkey, between September 2013 and May 2015. METHODOLOGY: Forty-three lesions [pancreas adenocarcinoma (n=25)], pancreatitis (n=10), benign lesion (n=8)] were utilized with diffusion-weighted magnetic resonance imaging with multiple b-values. Different ADC maps of diffusion weighted images by using b-values were acquired. RESULTS: The median ADC at all b values for malignant lesions was significantly different from that for benign lesions (p<0.001). When ADCs at all b values were compared between benign lesions/normal parenchyma and malignant lesions/normal parenchyma, there was a significant statistical difference in all b values between benign and malignant lesions except at b 50 and b 200 (p<0.05). The lesion/normal parenchyma ADC ratio for b 600 value (AUC=0.804) was more effective than the lesion ADC for b 600 value (AUC=0.766) in differentiation of benign and malignant lesions. The specificity and sensitivity of the lesion/normal parenchyma ADC ratio were higher than those of ADC values of lesions. When the ADC was compared between benign lesions and pancreatitis, a significant difference was found at all b values (p<0.001). There was not a statistically significant difference between the ADC for pancreatitis and that for malignant lesions at any b value combinations (p>0.05). CONCLUSION: Diffusion-weighted magnetic resonance images can be helpful in differentiation of pancreatic carcinoma and benign lesions. Lesion ADC / normal parenchyma ADC ratios are more important than lesion ADC values in assessment of pancreatic lesions.

Portal venous system aneurysms: imaging, clinical findings, and a possible new etiologic factor.

OBJECTIVE: The aims of this study were to present the prevalence, imaging and clinical findings, and possible causes of portal venous system aneurysms. MATERIALS AND METHODS: From 1998 to 2006, a total of 38 portal venous system aneurysms identified in 25 patients were retrospectively reviewed. The data of seven patients diagnosed using color Doppler sonography or CT before March 2004 were not consecutive, but the data recorded thereafter comprised the analysis of 4,186 consecutive patients who underwent routine abdominal MDCT. The patients were 14 men and 11 women (mean age -/+ SD, 53 -/+ 17 years). RESULTS: The prevalence of portal venous system aneurysm among 4,186 consecutive patients was 0.43%. There were no differences with respect to patient age, patient sex, and intrahepatic or extrahepatic location of aneurysm between those with and those without portal venous system aneurysm. Seven of the 25 patients with portal venous system aneurysm were symptomatic because of portal vein thrombosis, and six of them had recurrence. These patients had significantly larger aneurysms than those without symptoms. Four of those seven symptomatic patients evaluated for thrombophilia had an underlying defect. Other associated findings were splenomegaly (n = 16), portal hypertension (n = 8), cirrhosis (n = 3), psoriasis (n = 2), portal vein variation (n = 1), chronic pancreatitis (n = 1), and cutis laxa (n =1). CONCLUSION: Portal venous system aneurysms were rare in our study group but occurred more frequently than previously thought. All thrombosed aneurysms, most with a recurrence, were symptomatic and larger in patients with symptoms of portal venous system aneurysm than in those without symptoms. There were no differences among patients with portal venous system aneurysm and those without portal venous system aneurysm with respect to patient age and patient sex. Among those with aneurysms, there was no difference between subjects with intrahepatic versus extrahepatic aneurysms. A thrombophilic defect probably played a role in development of thrombosis in the portal venous system aneurysm.

Interruption or congenital stenosis of the inferior vena cava: prevalence, imaging, and clinical findings.

OBJECTIVE: To present the prevalence, clinical, and imaging findings of interruption or congenital stenotic lesions of the inferior vena cava (IVC), associated malformations, and their clinical relevance. MATERIALS AND METHODS: Between March 2004 and March 2006, 7972 patients who had undergone consecutive routine abdominal multidetector row computed tomography were analyzed for interruption or stenotic lesion of the IVC. RESULTS: Prevalence of interruption (n=8) or congenital stenosis (n=4) of the IVC occurred in 12 (0.15%) of 7972 patients. Four patients with interruption and four patients with congenital stenosis of the IVC were symptomatic with DVT (n=4), leg swelling (n=4), leg pain (n=2), lower extremity varices (n=2), hepatic vein thrombosis (n=1), and hematochezia (n=1). All four of the asymptomatic patients were from the interruption group, and these patients had interrupted IVC with well-developed azygos/hemiazygos continuation. Eight symptomatic patients did not have a well-developed azygos/hemiazygos continuation, and drainage of lower extremity was mainly from collateral veins. Additional findings in eight symptomatic patients were abdominal venous collaterals (n=8), venous aneurysm (n=2), lower extremity varices (n=2), varicocele (n=2), and pelvic varices (n=1). CONCLUSION: Interruption or stenosis of the IVC are rare on routine abdominal CT examinations and may cause different clinical findings depending on the variant drainage patterns or collaterals. Interrupted IVC is commonly asymptomatic if associated with well-developed azygos/hemiazygos continuation, whereas commonly symptomatic if well-developed azygos/hemiazygos continuation is not present.

Venous variants and anomalies on routine abdominal multi-detector row CT.

OBJECTIVE: This study aims to determine the types and prevalence rates of anatomic variations of the hepatic veins, portal vein, inferior vena cava and renal veins, and to establish statistical correlations between various anomalies and frequency differences between male and female using multi-detector row computed tomography (CT). MATERIALS AND METHODS: One thousand one hundred and twenty patients (588 men, 532 women) were evaluated with routine abdominal CT. Frequencies of different variants were noted and compared, and correlations between three categories of variation were tested. RESULTS: In total, 1261 abdominal vein variants and anomalies were identified in 756 (67.5%) of 1120 patients. Six hundred and forty-two hepatic vein variants were detected in 468 (41.8%) patients. One or more inferior right hepatic veins were identified in 356 (31.8%) individuals, and tributary hepatic veins were detected in 147 (13.1%) patients. Portal vein variations and anomalies were observed in 307 (27.4%) cases. The most frequent of these was trifurcation (139 patients, 12.4%). A total of 311 inferior vena cava and renal vein variants were identified in 258 (23%) cases. Six patients (0.5%) exhibited inferior vena cava anomalies, 62 (5.5%) had circumaortic renal veins, 53 (4.7%) had retroaortic renal veins, and 210 (18.8%) had multiple renal veins. CONCLUSION: The prevalence of abdominal vein variations is high, and routine abdominal CT demonstrates these abnormalities very well. The data suggest that hepatic vein variants and multiple right renal veins are more frequent in women than in men, and that hepatic vein variation is correlated with portal vein variation.