Bladder involvement in placenta accreta spectrum disorder with placenta previa: MRI findings and outcomes correlation.

BACKGROUND: Placental accreta spectrum (PAS) disorder with bladder involvement can be associated with maternal and neonatal morbidity. Magnetic resonance imaging (MRI) may provide accurate preoperative diagnoses. OBJECTIVE: This study had 2 aims: to retrospectively review the MRI findings for bladder involvement in PAS with placental previa and to correlate bladder involvement with maternal and neonatal outcomes. MATERIALS AND METHODS: MRI images of 48 patients with severe PAS (increta and percreta) with placenta previa/low-lying placenta were evaluated by 2 experienced radiologists blinded to the final diagnoses. Nine MRI findings and stepwise logistic regression analysis were assessed to identify predictive MRI findings for bladder involvement. The correlations between PAS patients with bladder involvement and clinical outcomes were analyzed using Fisher's exact test. RESULTS: Of the 48 patients, 27 did not have bladder involvement, while 21 did. Logistic regression analysis identified 2 predictive MRI features for bladder involvement. They were abnormal vascularization (OR,6.94; 95 %CI,1.05-45.75) and loss of the chemical shift line at the uterovesical interface (OR, 4.41; 95 %CI, 0.63-30.98). The sensitivity and specificity of the combined MRI features were 38.1 % and 100 %, respectively (p = 0.001). A significant correlation was found between bladder involvement and massive blood loss during surgery (p = 0.022). CONCLUSIONS: PAS with bladder involvement was significantly correlated with massive surgical blood loss. Prenatally, the disorder was predicted with high specificity by the combination of loss of chemical shift artifacts in the steady-state free precession sequence and abnormal vascularization at the uterovesical interface on MRI.

Read-out Segmented Echo Planar Imaging with Two-Dimensional Navigator Correction (RESOLVE): An Alternative Sequence to Improve Image Quality on Diffusion-Weighted Imaging of Prostate.

OBJECTIVE: We aimed to investigate if the use of read-out segmented echoplanar imaging with additional two-dimensional navigator correction (Readout Segmentation of Long Variable Echo, RESOLVE) for acquiring prostate diffusion-weighted imaging (DWI) improves image quality, compared to single-shot echoplanar imaging (ss-EPI). METHODS: This single-center prospective study cohort included 162 males with suspected prostate cancer, who underwent 3 Tesla multiparametric MRI (3T-mpMRI). Two abdominal radiologists, blinded to the clinical information, separately reviewed each 3T-mpMRI study to rank geometrical distortion, degree of rectal distention, lesion conspicuity, and anatomic details delineation first on ss-EPI-DWI and later on RESOLVE-DWI using 5-point scales (1 = excellent, 5 = poor). The average of the ranking scores given by two readers was generated and used as the final score. RESULTS: There was good-to-excellent interreader agreement for scoring image quality parameters on both ss-EPI and RESOLVE. Geometrical distortion scores > 3 was seen in 12.3% (20/162) of ss-EPI images, with all having geometrical distortion score <3 on RESOLVE (p < .001). The mean image distortion score was significantly less on RESOLVE than ss-EPI (1.16 vs 1.61, p < .01 regardless of rectal gas, p< .05 when stratified by the degree of rectal distention ). RESOLVE was superior to ss-EPI for lesion conspicuity (mean 1.35 vs 1.53, p< .002) and anatomic delineation (2.60 vs 2.68, p< .001) of prostate on DWI. CONCLUSION: Compared to conventional ss-EPI, the use of RESOLVE for acquisition of prostate DWI resulted in significantly enhanced image quality and reduced geometrical distortion. ADVANCES IN KNOWLEDGE: RESOLVE could be an alternative or replacement of ss-EPI for acquiring prostate DWI with significantly less geometrical distortion and significantly improved lesion conspicuity and anatomic delineation.

Head-to-Head Comparison of 68Ga-PSMA-11 PET/CT and mpMRI with a Histopathology Gold Standard in the Detection, Intraprostatic Localization, and Determination of Local Extension of Primary Prostate Cancer: Results from a Prospective Single-Center Imaging Trial.

The role of prostate-specific membrane antigen (PSMA)-targeted PET in comparison to multiparametric MRI (mpMRI) in the evaluation of intraprostatic cancer foci is not well defined. The aim of our study was to compare the diagnostic performance of 68Ga-PSMA-11 PET/CT (PSMA PET/CT), mpMRI, and PSMA PET/CT + mpMRI using 3 independent masked readers for each modality and with histopathology as the gold standard in the detection, intraprostatic localization, and determination of local extension of primary prostate cancer. Methods: Patients with intermediate- or high-risk prostate cancer who underwent PSMA PET/CT as part of a prospective trial (NCT03368547) and mpMRI before radical prostatectomy were included. Each imaging modality was interpreted by 3 independent readers who were unaware of the other modality result. A central majority rule was applied (2:1). Pathologic examination of whole-mount slices was used as the gold standard. Imaging scans and whole-mount slices were interpreted using the same standardized approach on a segment level and a lesion level. A "neighboring" approach was used to define imaging-pathology correlation for the detection of individual prostate cancer foci. Accuracy in determining the location, extraprostatic extension (EPE), and seminal vesicle invasion (SVI) of prostate cancer foci was assessed using receiver-operating-characteristic curve analysis. Interreader agreement was calculated using intraclass correlation coefficient analysis. Results: The final analysis included 74 patients (14 [19%] with intermediate risk and 60 [81%] with high risk). The cancer detection rate (lesion-based analysis) was 85%, 83%, and 87% for PSMA PET/CT, mpMRI, and PSMA PET/CT + mpMRI, respectively. The change in AUC was statistically significant between PSMA PET/CT + mpMRI and the 2 imaging modalities alone for delineation of tumor localization (segment-based analysis) (P < 0.001) but not between PSMA PET/CT and mpMRI (P = 0.093). mpMRI outperformed PSMA PET/CT in detecting EPE (P = 0.002) and SVI (P = 0.001). In the segment-level analysis, intraclass correlation coefficient analysis showed moderate reliability among PSMA PET/CT and mpMRI readers using a 5-point Likert scale (range, 0.53-0.64). In the evaluation of T staging, poor reliability was found among PSMA PET/CT readers and poor to moderate reliability was found for mpMRI readers. Conclusion: PSMA PET/CT and mpMRI have similar accuracy in the detection and intraprostatic localization of prostate cancer foci. mpMRI performs better in identifying EPE and SVI. For the T-staging evaluation of intermediate to high-risk prostate cancer, mpMRI should still be considered the imaging modality of reference. Whenever available, PSMA PET/MRI or the coregistration or fusion of PSMA PET/CT and mpMRI (PSMA PET/CT + mpMRI) should be used as it improves tumor extent delineation.

Performance of Deep Learning and Genitourinary Radiologists in Detection of Prostate Cancer Using 3-T Multiparametric Magnetic Resonance Imaging.

BACKGROUND: Several deep learning-based techniques have been developed for prostate cancer (PCa) detection using multiparametric magnetic resonance imaging (mpMRI), but few of them have been rigorously evaluated relative to radiologists' performance or whole-mount histopathology (WMHP). PURPOSE: To compare the performance of a previously proposed deep learning algorithm, FocalNet, and expert radiologists in the detection of PCa on mpMRI with WMHP as the reference. STUDY TYPE: Retrospective, single-center study. SUBJECTS: A total of 553 patients (development cohort: 427 patients; evaluation cohort: 126 patients) who underwent 3-T mpMRI prior to radical prostatectomy from October 2010 to February 2018. FIELD STRENGTH/SEQUENCE: 3-T, T2-weighted imaging and diffusion-weighted imaging. ASSESSMENT: FocalNet was trained on the development cohort to predict PCa locations by detection points, with a confidence value for each point, on the evaluation cohort. Four fellowship-trained genitourinary (GU) radiologists independently evaluated the evaluation cohort to detect suspicious PCa foci, annotate detection point locations, and assign a five-point suspicion score (1: least suspicious, 5: most suspicious) for each annotated detection point. The PCa detection performance of FocalNet and radiologists were evaluated by the lesion detection sensitivity vs. the number of false-positive detections at different thresholds on suspicion scores. Clinically significant lesions: Gleason Group (GG) ≥ 2 or pathological size ≥ 10 mm. Index lesions: the highest GG and the largest pathological size (secondary). STATISTICAL TESTS: Bootstrap hypothesis test for the detection sensitivity between radiologists and FocalNet. RESULTS: For the overall differential detection sensitivity, FocalNet was 5.1% and 4.7% below the radiologists for clinically significant and index lesions, respectively; however, the differences were not statistically significant (P = 0.413 and P = 0.282, respectively). DATA CONCLUSION: FocalNet achieved slightly lower but not statistically significant PCa detection performance compared with GU radiologists. Compared with radiologists, FocalNet demonstrated similar detection performance for a highly sensitive setting (suspicion score ≥ 1) or a highly specific setting (suspicion score = 5), while lower performance in between. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2.

Efficacy of 3T Multiparametric MR Imaging followed by 3T in-Bore MR-Guided Biopsy for Detection of Clinically Significant Prostate Cancer Based on PIRADSv2.1 Score.

PURPOSE: To evaluate the diagnostic yield of 3T in-Bore magnetic resonance-guided biopsy (3T IB-MRGB) for detection of clinically significant prostate cancer (csPCa), based on assessment using the Prostate Imaging Reporting and Data System version 2.1 (PIRADSv2.1). MATERIALS AND METHODS: This single-center study examined individuals who underwent 3T multiparametric prostate magnetic resonance (MR) imaging and subsequent 3T IB-MRGB. The final study cohort included 379 men (with 475 targets) divided into 3 subcohorts: biopsy-naïve men (n = 123), individuals with a history of negative trans-rectal-ultrasonography (TRUS) biopsy results (n = 106), and men with low-grade PCa under active surveillance (n = 150). csPCa was defined as having a Gleason score (GS) ≥3+4. RESULTS: 3T IB-MRGB detected PCa and csPCa in 69.1% (262 of 379) and 50.3% (193 of 379) of patients, respectively. The PCa and csPCa detection rates per target were 64.2% (305 of 475) and 43.8% (208 of 475), respectively. The rate of urosepsis, treated with intravenous antibiotics, was 1% (4 patients). In TRUS biopsy negative results and biopsy-naïve subcohorts, csPCa was found in 36.8% (39 of 106) and 52.8% (65 of 123), respectively. In 50.7% (76 of 150) of the active surveillance subcohort, 3T IB-MRGB upgraded the GS assigned in prior TRUS biopsies. Positive predictive values of PIRADSv2.1 categories 3, 4, and 5 for csPCa detection were 24.8%, 44.4%, and 67.1%, respectively. Higher PIRADSv2.1 categories were significantly associated with PCa (odds ratio [OR], 3.97; 95% confidence interval [CI], 2.98-5.28) and csPCa (OR, 1.41; 95% CI, 1.03-1.94) detection. Of 137 PIRADSv2 category 3 lesions, 28 were downgraded to PIRADSv2.1 category 2, in which there were no occurrences of csPCa in histology. CONCLUSIONS: Use of 3T IB-MRGB resulted in detection of csPCa in 50.9% of individuals. 3T IB-MRGB has a high diagnostic yield in individuals with negative TRUS biopsy results and those under active surveillance. The PIRADSv2.1 category is a strong predictor of PCa and csPCa detection.

Prospective comparison of transient elastography, point shear wave elastography, APRI and FIB-4 for staging liver fibrosis in chronic viral hepatitis.

Ultrasound-based elastography and serum indexes have been individually validated as noninvasive methods for staging liver fibrosis in chronic viral hepatitis. We aimed to compare the accuracy of transient elastography (TE), shear wave elastography (SWE), aspartate aminotransferase to platelet index (APRI) and Fibrosis-4 index (FIB-4) with the METAVIR liver fibrosis staging in viral hepatitis patients. We enrolled 121 treatment-naïve chronic hepatitis B and C monoinfected patients. All underwent liver biopsy had biochemistry tests and liver stiffness measurements by TE using M and XL probes followed by point SWE performed on the same day. The accuracy of each method for predicting different fibrosis stages was demonstrated as an area under the receiver operating characteristic (AUROC) curves. The AUROCs of TE using M and XL probes, SWE, APRI and FIB-4 were 0.771, 0.761, 0.700, 0.698 and 0.697, respectively, for significant fibrosis; 0.974, 0.973, 0.929, 0.738 and 0.859, respectively, for advanced fibrosis; and 0.954, 0.949, 0.962, 0.765 and 0.962, respectively, for cirrhosis. TE using the M probe was comparable to the XL probe in detecting all fibrosis stages. TE was superior to SWE for assessing significant fibrosis and advanced fibrosis. For cirrhosis, the performances of TE, SWE and FIB-4 were similar. APRI was least accurate in liver fibrosis staging. To conclude, for patients with viral hepatitis, TE using either M or XL probe is an effective noninvasive test for assessing liver fibrosis, particularly advanced fibrosis and cirrhosis, while SWE and FIB-4 possess an excellent accuracy in predicting cirrhosis.

Correlation Between Apparent Diffusion Coefficient Values of the Renal Parenchyma and Estimated Glomerular Filtration Rates on 3-T Diffusion-Weighted Echo-Planar Magnetic Resonance Imaging.

OBJECTIVE: To evaluate the relationship between the apparent diffusion coefficient (ADC) values of renal parenchyma and estimated glomerular filtration rates (eGFR). METHODS: Data on 216 patients examined by 3-T magnetic resonance imaging for various reasons were retrospectively collected. RESULTS: There was a significant linear correlation between the ADC values and eGFRs (r = 0.254, P < 0.001). The ADC values in patients with an eGFR of less than 60 mL/min per 1.73 m were significantly lower than those with an eGFR of 60 mL/min per 1.73 m or greater. The mean ADC value of patients with grouped stage 2 disease was significantly higher than those with grouped stage 3 of chronic kidney disease (P < 0.01). CONCLUSIONS: The ADC value of renal parenchyma may be a promising marker for the determination of patients with normal to mild reduction in renal function (eGFR ≥60 mL/min per 1.73 m) versus those with a moderate to severe reduction in renal function (eGFR <60 mL/min per 1.73 m).

Diagnostic performance of qualitative and quantitative shear wave elastography in differentiating malignant from benign breast masses, and association with the histological prognostic factors.

BACKGROUND: To determine the diagnostic performance of qualitative and quantitative shear wave elastography (SWE) and the optimal cutoff values of the quantitative SWE parameters in differentiating malignant from benign breast masses, and to evaluate the association between the quantitative SWE parameters and histological prognostic factors. METHODS: A gray scale ultrasound and SWE were prospectively performed on a total of 244 breast masses (148 benign, and 96 malignant) in 228 consecutive patients before an ultrasound-guided needle biopsy. The qualitative SWE and quantitative SWE parameters (the mean elasticity, maximum elasticity, and elasticity ratio) were measured in each mass. The diagnostic performance of SWE and the optimal cutoff values of the quantitative SWE parameters were obtained. An association analysis of the parameters and histological prognostic factors was performed. RESULTS: The malignant masses had a more heterogeneous pattern on the qualitative SWE than benign masses (P<0.001). The quantitative SWE parameters of the malignant masses were higher than those of the benign masses (P<0.001); the mean elasticity, maximum elasticity, and elasticity ratio of the benign masses were 19.73 kPa, 23.98 kPa, and 2.78, respectively; and the mean elasticity, maximum elasticity, and elasticity ratio of the malignant masses were 88.13 kPa, 98.48 kPa, and 10.64, respectively. The optimal cutoff value of the mean elasticity was 30 kPa, of the maximum elasticity was 36 kPa, and of the elasticity ratio was 4.5. The maximum elasticity had the highest AUC. Combining the three SWE parameters to differentiate between the malignant and benign masses increased the negative predictive value (NPV), which correctly downgraded 72.73% of BI-RADS category 4A masses to BI-RADS category 3. No statistically significant association was found between the quantitative SWE parameters and the tumor grading, tumor types, axillary lymph node statuses, or molecular subtypes of the breast cancers (P>0.05). CONCLUSIONS: The qualitative and quantitative SWE provided good diagnostic performance in differentiating malignant and benign masses. The maximum elasticity of the quantitative SWE parameters had the best diagnostic performance. Adding the three combined quantitative SWE parameters to the BI-RADS category 4A masses potentially downgraded them to BI-RADS category 3 and avoided unnecessary biopsies. No statistically significant association was found between the quantitative SWE parameters and the histological prognostic factors.

Clinical, mammographic, and ultrasonographic characteristics of diabetic mastopathy: A case series.

PURPOSE: Diabetic mastopathy (DMP) is a rare benign breast lesion that mimics breast cancer on ultrasound. Our aims were to identify patient characteristics and imaging features of the disease. METHODS: We conducted retrospective searches of our database for DMP lesions that were pathologically confirmed between January 2004 and November 2015. Mammographic and ultrasound features were reviewed by two experienced radiologists. RESULTS: Twelve women were identified with 16 lesions. Most patients (83%) had type 2 diabetes mellitus (DM) and over half were insulin-dependent (58.3%), with a mean time of 16.9 years between the diagnosis of DM and that of DMP. There were negative findings on mammography for 46.7% of the lesions, including larger-sized lesions. Ultrasound revealed various features, including irregular shape (81.3%), indistinct margins (100%), parallel orientation to the chest wall (93.8%), marked hypoechogenicity (87.5%), and posterior shadowing (62.5%). CONCLUSIONS: DMP was more common in patients with longstanding DM; in particular, type 2 DM and insulin-dependent patients. DMP lesions were usually occult on mammography, despite the relatively large size of DMP, which may help distinguish DMP from invasive cancer. Ultrasound detected several features that are also present in invasive cancer, making tissue sampling necessary to distinguish these.

Leukemic arthritis and severe hypercalcemia in a man with chronic myeloid leukemia: a case report and review of the literature.

BACKGROUND: Patients with chronic myeloid leukemia typically present with high white blood cell counts revealed during annual checkups. Leukemic arthritis and hypercalcemia are rare manifestations in patients with chronic myeloid leukemia. CASE PRESENTATION: A 35-year-old Thai man who had been diagnosed with chronic myeloid leukemia in the chronic phase developed blast crisis while he was receiving ongoing treatment with imatinib at 400 mg/day. Initially, he presented with oligoarthritis in both knees and ankles. A bone scintigraphy showed a prominent bony uptake, with a symmetrical, increased uptake in many bone areas. Induction therapy with a 7 + 3 induction regimen was prescribed in conjunction with 600 mg of imatinib once daily before switching to 140 mg of dasatinib. He subsequently developed severe hypercalcemia (total serum calcium of 17.8 mg/dL), with generalized osteolytic lesions detected on a bone survey. His serum vitamin D level was 50.64 ng/mL, while the serum parathyroid hormone level was 9.82 pg/mL. Despite the administration of an aggressive intravenously administered hydration, intravenously administered calcitonin, and 600 mg/day of imatinib, the severe hypercalcemia was refractory. We therefore decided to prescribe 20 mg/day of intravenously administered dexamethasone; fortunately, his serum calcium level decreased dramatically to normal range within a few days. CONCLUSIONS: Although leukemic arthritis and severe hypercalcemia are extraordinary presentations in patients with chronic myeloid leukemia, the advanced phase of the disease might bring on these symptoms. Apart from parathyroid hormone-related protein-related hypercalcemia, vitamin D is a mechanism of humoral-mediated hypercalcemia.

MRI of placenta percreta: differentiation from other entities of placental adhesive disorder.

OBJECTIVES: To retrospectively review the MRI findings of placenta percreta and identify those helpful for differentiation from non-placenta percreta. MATERIALS AND METHODS: The MRI images of 21 patients with a preliminary diagnosis of placental adhesive disorder scanned between 2005 and 2014 were evaluated. Radiologists blinded to the final diagnosis evaluated six previously described MRI findings of placenta adhesive disorder. The sensitivity, specificity, accuracy, negative predictive value (NPV), and positive predictive value (PPV) of MRI for the diagnosis of placenta percreta were also calculated. RESULTS: The study included 12 cases of placenta percreta and 9 cases of non-placenta percreta. Invasion of placental tissue outside the uterus was found only in placenta percreta (p = 0.045; sensitivity 41.7 %; specificity 100 %). All placenta percreta cases also had a moderate to marked degree of heterogeneous placental signal intensity (p = 0.063; sensitivity 100 %; specificity 33.3 %). The size of the dark bands on T2-weighted imaging, and the presence of disorganized intra-placental vessels, showed no statistically significant difference between placenta percreta and non-placenta percreta. The sensitivity, specificity, NPV, PPV, and accuracy of MRI for detection of placenta percreta were 91.7, 44, 80, 68, and 71.4 %, respectively. CONCLUSIONS: MRI is recommended for the evaluation of placenta percreta, with the most specific signs including the invasion of placental tissue outside the uterus on B-FFE sequences, and consideration of the degree of placental signal heterogeneity. The size of the T2 dark band alone, or bizarre disorganized intra-placental vessels, did not correlate with the severity of invasion.

Alvarado score: can it reduce unnecessary CT scans for evaluation of acute appendicitis?

OBJECTIVE: The objective of the study is to assess the utility of Alvarado score in the diagnosis of acute appendicitis and the utility of computed tomographic (CT) scan for evaluation of acute appendicitis when stratified by Alvarado scores. MATERIALS AND METHODS: Retrospective cohort study comprised adult patients who underwent abdominal CT for suspected acute appendicitis between January 2006 and December 2009. Two abdominal radiologists independently reviewed the CT scans; any discrepancies were resolved by a consensus review. Alvarado scores were calculated and categorized as low (0-3), equivocal (4-6), or high (7-10) probability for appendicitis. The diagnostic utility of CT scans and Alvarado score for acute appendicitis were compared with the criterion standard of combined medical chart review and pathology findings. RESULTS: In a cohort of 158 subjects, 73 (46.2%) had clinical diagnoses of acute appendicitis. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of CT scan in the diagnosis of acute appendicitis were 97.5%, 98.6%, 96.5%, 96.0%, and 98.8%, respectively. The mean Alvarado score for subjects with complicated appendicitis was significantly higher (7.95) than subjects with uncomplicated appendicitis (6.67) and those with other diagnoses (5.95). Acute appendicitis was confirmed in 2 (13.3%) of 15 subjects with low probability Alvarado scores, 16 (30.8%) of 52 subjects with equivocal scores, and 55 (60.4%) of 91 subjects with high probability scores. CONCLUSION: The CT scan had high diagnostic utility for acute appendicitis. The Alvarado score was not a reliable independent predictive tool for acute appendicitis and could not replace CT scan.

Diagnosis of bowel obstruction: added value of multiplanar reformations from multidetector CT in comparison with axial planes alone.

OBJECTIVE: To retrospectively assess the benefit of multiplanar reformations from multidetector CT for diagnosis of bowel obstruction in comparison with axial planes alone. MATERIAL AND METHOD: Between October 2008 and May 2010, included the consecutive 75 patients/76 CT studies who underwent multidetector CT at Siriraj Hospital to rule out bowel obstruction. Fifty-seven patients of 58 studies confirmed the final diagnosis of bowel obstruction by surgical proof or obstructive symptoms relief from conservative treatments; divided into 25 small bowel and 33 large bowel obstructions. Two independent readers, blinded to diagnosis, interpreted for bowel obstruction firstly using axial slices alone, then immediately scoring MPR images including axial, coronal, sagittal, and oblique reformations from the same study. Confidence score was applied In case of radiological diagnosis of bowel obstruction, the findings of transition point, cause, severity, and complication were also evaluated. RESULTS: CT diagnosis of bowel obstruction was made 54 on axial image alones and 55 on axial image plus MPR, leading to the sensitivity of 93.1% and specificity of 77.8% on the axial scans alone and the sensitivity of 94.8% and specificity of 72.2% on the axial plus MPR, respectively. The axial plus MPR images helped correct diagnosis and increased confidence score in one case of low grade, small bowel obstruction. Accuracy in diagnosis of between large bowel obstruction and small bowel obstruction was 90% and 88.5% on axial scans alone and 90% and 92.3% on axial plus MPR scans, respectively. CONCLUSION: The axial scan CT is an appropriate modality for the patients suspected bowel obstruction. The authors encourage using MPR as the adjunct tool to the axial images, especially in the case suspected small bowel obstruction. MPR help increasing diagnostic confidence and confirming the findings found on axial image.

Renal vascular variants in living related renal donors: evaluation with CT angiography.

BACKGROUND: Renal vascular variants may complicate the surgical techniques of living related renal transplantation. Renal computed tomographic (CT) angiography is now well accepted for preoperative renal vascular mapping in living related renal donors. OBJECTIVE: To study the prevalence of renal vascular variants in living related renal donors using CT angiography. MATERIAL AND METHOD: Preoperative renal CT angiography of 65 consecutive living related renal donors were retrospectively reviewed by two abdominal radiologists on a 3-D workstation. The number and branching patterns of bilateral renal arteries and veins, as well as the presence of renal arterial and venous variants were described. RESULTS: Supernumerary renal arteries and early branching were present in 18.5% and 12.8% respectively on the right kidneys and 27.7% and 22.4% respectively on the left kidneys. The prevalence of precaval right renal artery was 4.6%. Supernumerary renal veins were present in 35.4% and 1.5% on the right and left kidneys, respectively. Late confluences of left renal veins were identified in 1.5% of left kidneys. Other venous anomalies included 1.5% duplicated inferior vena cava (IVC), 1.5% circumaortic left renal vein, 1.5% retroaortic left renal vein, 1.5% outsized left gonadal veins drained into the left renal vein, and 6.2% right gonadal vein drained into the right renal vein. CONCLUSION: Renal vascular anatomical variants were common. The surgeons and the radiologists should be aware of these variants to prevent postoperative complications.