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Objective: To evaluate whether artificial intelligence (AI) based automatic image analysis utilising convolutional neural networks (CNNs) can be used to evaluate computed tomography urography (CTU) for the presence of urinary bladder cancer (UBC) in patients with macroscopic hematuria., Methods: Our study included patients who had undergone evaluation for macroscopic hematuria. A CNN-based AI model was trained and validated on the CTUs included in the study on a dedicated research platform (Recomia.org). Sensitivity and specificity were calculated to assess the performance of the AI model. Cystoscopy findings were used as the reference method., Results: The training cohort comprised a total of 530 patients. Following the optimisation process, we developed the last version of our AI model. Subsequently, we utilised the model in the validation cohort which included an additional 400 patients (including 239 patients with UBC). The AI model had a sensitivity of 0.83 (95% confidence intervals [CI], 0.76-0.89), specificity of 0.76 (95% CI 0.67-0.84), and a negative predictive value (NPV) of 0.97 (95% CI 0.95-0.98). The majority of tumours in the false negative group (n = 24) were solitary (67%) and smaller than 1 cm (50%), with the majority of patients having cTaG1-2 (71%)., Conclusions: We developed and tested an AI model for automatic image analysis of CTUs to detect UBC in patients with macroscopic hematuria. This model showed promising results with a high detection rate and excessive NPV. Further developments could lead to a decreased need for invasive investigations and prioritising patients with serious tumours.

Continent diversion with orthotopic neobladder is the most upcoming form of urinary diversion postradical cystectomy. This allows patients to void through the native urethra preserving the maximal quality of life. These patients with greater life expectancies increasingly present with a wide range of late complications, which also include local recurrences involving neobladder. Such presentations on surveillance scans can be challenging for radiologists unfamiliar with expected post-surgical anatomy and usual sites of local recurrences. Tumour in neobladder, although rare, has predilection concerning specific sites of involvement and few distinct histological types. Major subtypes of such recurrences with corresponding radiological features on multimodality imaging have been discussed in this article. Management of such cases with revision of diversions is challenging, and surgeons expect a meticulous read of such scans before contemplating pelvic clearance and secondary diversions. This pictorial review aims to appraise the literature related to various primary and secondary types of tumours involving reservoir and anastomotic sites in an orthotopic neobladder, their relative incidences and illustrate salient imaging points with case examples.

Purpose: We report the reliability of computerized tomography urography and ureteroscopy in the diagnosis and management of upper tract urothelial carcinoma., Materials and Methods: From 2015 to November 2018 we prospectively collected and retrospectively analyzed 244 cases of ureteroscopy with available preoperative computerized tomography urography. Computerized tomography urography was categorized as positive, suspicious, unlikely and negative. Correspondence between imaging, ureteroscopy and histology was analyzed. The therapeutic indication, based on 2020 EAU Guidelines and patient clinical data, was recorded before and after ureteroscopy. Cohen's Kappa was used for agreement analysis. Logistic regression was used for prediction of positive ureteroscopy., Results: Ureteroscopy was positive for upper tract urothelial carcinoma in 107/115 (93%), 48/77 (62.3%), 15/27 (55.6%) and 12/25 (48%) cases with positive, suspicious, unlikely and negative computerized tomography urography, respectively. On cytohistology the result was confirmed in 164/182 (90.1%) cases. The positive predictive value of a filling defect, stenosis, thickening and hydronephrosis on computerized tomography urography was 87.7% (121/138 cases), 65.6% (21/32), 69.6% (64/92) and 79.7% (59/74), respectively. On multivariate analysis a filling defect (95% CI 2.76-11.5, OR 5.63, p <0.0001) or hydronephrosis (1.04-6.18, OR 2.52, p=0.04) was associated with ureteroscopy outcome. Among cases with positive computerized tomography urography and ureteroscopy, the lesions differed in dimensions (20/107), number (14/107) and site (11/107), for a total of 45/107 (42.1%) cases. The indication of elective treatment changed after ureteroscopy in 37/76 (48.1%) cases (Kappa=0.31), as 17/28 (60.7%), 11/20 (55%) and 11/28 (39.2%) indications were confirmed for endoscopic management, ureterectomy and nephroureterectomy, respectively., Conclusions: The complementary use of computerized tomography urography and ureteroscopy in the diagnostic workup of upper tract urothelial carcinoma should be evaluated.

Purpose: Retrograde pyelography (RPG) is used in some centers to further evaluate patients with incompletely opacified segments on CT urography (CTU). This study intends to evaluate the utility of this imaging combination in terms of the yield of abnormal findings on the follow up RPG., Methods: In this retrospective study, we searched the radiology database over a three-year period (11/1/2015-10/30/2018) for patients who had a CTU and then a diagnostic RPG within 180 days. Images and reports were reviewed from this period for patients who met the inclusion criteria., Results: 292 patients underwent a CTU with follow up RPG over the search period. 131/292 RPGs (44.9%) were performed because the CTU described at least one incompletely opacified ureteral segment. Of the 148 ureters evaluated in these 131 patients, 4 ureters (2.7%) showed an abnormality on follow up retrograde pyelogram-two revealed a stricture at the unfilled segment, and two revealed contour irregularity in the distal ureter (biopsy showed urothelial cell carcinoma in these two)., Conclusion: There is a relatively low yield for detecting ureteral abnormalities when a retrograde pyelogram is performed after a CTU to evaluate an incompletely opacified ureteral segment-2.7% in our study, with only two of these incompletely opacified segments containing urothelial cancer (1.4%). In these two cases, a ureteral abnormality was visible on the CTU and RPG would seem to have a very low yield for follow up of unopacified ureteral segments if the ureters are otherwise normal-appearing on CTU and there is no hydronephrosis.

Purpose: To compare frequency of new and recurrent urothelial cell carcinoma (UCC) among patients with and without pseudodiverticulosis on imaging., Methods: This retrospective case-control study compared all 113 sequential patients with ureteral pseudodiverticulosis on radiographic urography between 1/1/2002 and 12/31/2012. Six patients were lost to follow-up. 107 patients without pseudodiverticulosis were matched by imaging modality, clinical indication, and tumor grade. Known UCC and primary outcome of new or recurrent UCC were determined through pathology on cystoscopy or clinical follow-up., Results: Nearly half of patients with pseudodiverticulosis had known UCC at the time of imaging (49/107, 46%). Mean cystoscopy follow-up was 7.0 and 4.6 years for pseudodiverticulosis cases with and without known UCC, respectively, and 7.5 and 7.3 years for controls, respectively. Mean clinic follow-up was 7.5 and 6.0 years for pseudodiverticulosis cases with and without known UCC, respectively, and 6.4 and 7.6 years for controls, respectively. Among patients with known UCC at the time of imaging, similar rates of recurrent UCC were demonstrated on follow-up among patients with pseudodiverticulosis (6/49, 12%) and without (7/49, 14%). Among patients with no known history of UCC at the time of imaging, no patients with pseudodiverticulosis developed UCC on follow-up and 5% (3/58) of patients without pseudodiverticulosis developed UCC., Conclusion: Although half of patients with ureteral pseudodiverticulosis have a known diagnosis of UCC, the presence of pseudodiverticulosis did not signify an increased likelihood of developing new or recurrent UCC over the follow-up period.

Retrograde pyelography (RGP) is done to evaluate the collecting system when intravenous contrast studies are contraindicated due to renal insufficiency or prior adverse reactions. We report a patient who developed acute renal shutdown following bilateral RGP in the same sitting done for evaluation of positive malignant cytology of urine. A 65-year-old man on treatment for left stroke and hypertension, with a baseline serum creatinine of 1.9 mg/dl presented with painless haematuria for 2 months. Plain computed tomogram revealed a small papillary growth on the posterior wall of the urinary bladder. Transurethral resection revealed inflammatory atypia. As the patient continued to have haematuria, he was taken up for bilateral ureteric washings for cytology and bilateral RGP. A 5-Fr universal ureteral catheter was used to cannulate the ureters, urine was aspirated for cytology and 6 ml of 76% meglumine diatrizoate (1:2) was injected, and sufficient opacification with no abnormality or pyelosinus/venous or lymphatic reflux was noted. In the immediate postoperative period, he developed anuria and the serum creatinine rose to 3.6 mg/dl on postoperative day 1 and to 7.5 mg/dl on day 5. He needed three sessions of haemodialysis. Ultrasonography showed no hydroureteronephrosis. Urine output improved and his serum creatinine stabilized at the preoperative level of 1.8 mg/dl. The patient is doing well with stable renal function at 12 months. Although RGP is useful, it needs to be done with caution if a bilateral procedure is contemplated. This entity is seldom reported, and routine double-J stenting following unilateral/bilateral RGP also needs evaluation., Competing Interests: None

Purpose: To determine test characteristics of CT urography for detecting bladder cancer in patients with hematuria and those undergoing surveillance, and to analyze reasons for false-positive and false-negative results., Methods: A HIPAA-compliant, IRB-approved retrospective review of reports from 1623 CT urograms between 10/2010 and 12/31/2013 was performed. 710 examinations for hematuria or bladder cancer history were compared to cystoscopy performed within 6 months. Reference standard was surgical pathology or 1-year minimum clinical follow-up. False-positive and false-negative examinations were reviewed to determine reasons for errors., Results: Ninety-five bladder cancers were detected. CT urography accuracy: was 91.5% (650/710), sensitivity 86.3% (82/95), specificity 92.4% (568/615), positive predictive value 63.6% (82/129), and negative predictive value was 97.8% (568/581). Of 43 false positives, the majority of interpretation errors were due to benign prostatic hyperplasia (n = 12), trabeculated bladder (n = 9), and treatment changes (n = 8). Other causes include blood clots, mistaken normal anatomy, infectious/inflammatory changes, or had no cystoscopic correlate. Of 13 false negatives, 11 were due to technique, one to a large urinary residual, one to artifact. There were no errors in perception., Conclusion: CT urography is an accurate test for diagnosing bladder cancer; however, in protocols relying predominantly on excretory phase images, overall sensitivity remains insufficient to obviate cystoscopy. Awareness of bladder cancer mimics may reduce false-positive results. Improvements in CTU technique may reduce false-negative results.

Purpose: To evaluate the feasibility of using an objective computer-aided system to assess bladder cancer stage in CT Urography (CTU)., Materials and Methods: A dataset consisting of 84 bladder cancer lesions from 76 CTU cases was used to develop the computerized system for bladder cancer staging based on machine learning approaches. The cases were grouped into two classes based on pathological stage ≥ T2 or below T2, which is the decision threshold for neoadjuvant chemotherapy treatment clinically. There were 43 cancers below stage T2 and 41 cancers at stage T2 or above. All 84 lesions were automatically segmented using our previously developed auto-initialized cascaded level sets (AI-CALS) method. Morphological and texture features were extracted. The features were divided into subspaces of morphological features only, texture features only, and a combined set of both morphological and texture features. The dataset was split into Set 1 and Set 2 for two-fold cross-validation. Stepwise feature selection was used to select the most effective features. A linear discriminant analysis (LDA), a neural network (NN), a support vector machine (SVM), and a random forest (RAF) classifier were used to combine the features into a single score. The classification accuracy of the four classifiers was compared using the area under the receiver operating characteristic (ROC) curve (A z )., Results: Based on the texture features only, the LDA classifier achieved a test A z of 0.91 on Set 1 and a test A z of 0.88 on Set 2. The test A z of the NN classifier for Set 1 and Set 2 were 0.89 and 0.92, respectively. The SVM classifier achieved test A z of 0.91 on Set 1 and test A z of 0.89 on Set 2. The test A z of the RAF classifier for Set 1 and Set 2 was 0.89 and 0.97, respectively. The morphological features alone, the texture features alone, and the combined feature set achieved comparable classification performance., Conclusion: The predictive model developed in this study shows promise as a classification tool for stratifying bladder cancer into two staging categories: greater than or equal to stage T2 and below stage T2., (© 2017 American Association of Physicists in Medicine.)

Objectives: To evaluate the utility of virtual cystoscopy (VC) performed with CT urography in patients being studied under gross hematuria or patients being followed-up after a previous bladder cancer and compare the results with those obtained with gold standard technique (optical cystoscopy)., Methods: Retrospective study of 117 patients who were referred for VC by the Urology Department between May 2014 and May 2015. Those patients presented with gross hematuria or they were previously treated patients from bladder cancer being followed up. These patients were evaluated with MDCT and virtual cystoscopy after distending the bladder with air. The results were compared with those obtained with optical cystoscopy which was performed no more than a week after., Results: The global sensitivity and specificity of VC were 81,8 and 92,1%. Aditional findings detected in CT urography were an aortic dissection, urinary lithiasis and colonic metastasis., Conclusion: VC seems an useful technique in the diagnosis and follow-up for bladder cancer with a good correlation with OC. The main limitations are the impossibility of biopsy during the procedure and the detection of erythematous lesions. Collateral findings can be detected performed with CT urography although the high radiation exposure does not recommend their combined use., (Copyright © 2017 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.)

Purpose: To determine the accuracy of split-bolus CT urogram (SB-CTU) without special maneuvers for ureteral distention in diagnosing upper urinary tract urothelial carcinoma (UCA)., Materials and Methods: A hospital database was searched from 1/1/10, to 9/1/15, for SB-CTU exams without special maneuvers for ureteral distention. Accuracy of SB-CTU for detecting upper and lower urinary tract UCA was computed by comparing the prospective radiology report with cystoscopy, ureteroscopy, and/or urologic clinical follow-up. Patients with less than 12 months of clinical follow-up were excluded., Results: 339 studies were identified in 334 patients (60% male 40% female, avg. age 64). 119 studies were performed for microhematuria, 150 for gross hematuria, 13 for hematuria not otherwise specified, 57 for history of UCA, and one for a collecting system mass on a prior CT. There were five upper tract and 33 bladder tumors with overall prevalence of 1.5% and 9.7%, respectively. The prevalence varied significantly with patient age and clinical indication for SB-CTU. There were one false negative and four false positives for upper urinary tract UCA. Sensitivity, specificity, positive predictive value, and negative predictive value for detecting upper tract and bladder tumors were 80%, 99%, 44%, and 100%, respectively, and 55%, 98%, 78%, and 95%, respectively., Conclusion: Based on this study, SB-CTU without special maneuvers for ureteral distention is highly sensitive for detecting upper tract UCA, although with a low positive predictive value, false positives do occur. The clinical utility of increasing accuracy in diagnosing this low-prevalence disease through other more complex CT urogram protocols should be weighed against the added cost and radiation dose associated with these protocols.

Computed tomography (CT) urography is the best noninvasive method of evaluating the upper urinary tract for urothelial malignancies. However, the utility of CT urography is heavily contingent on the use of proper image acquisition protocols. This article focuses on the appropriate protocols for optimizing CT urography acquisitions, including contrast administration and the timing of imaging acquisitions, as well as the use of ancillary techniques to increase collecting system distention. In addition, imaging findings are discussed that should raise concern for urothelial carcinoma at each of the 3 segments of the urinary tract: the intrarenal collecting systems, ureters, and bladder., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Purpose: To investigate the feasibility of high temporal resolution quantitative perfusion imaging of bladder tumors performed simultaneously with conventional multi-phase MR urography (MRU) using a novel free-breathing continuously acquired radial MRI sequence with compressed-sensing reconstruction., Methods: 22 patients with bladder lesions underwent MRU using GRASP (Golden-angle RAdial Sparse Parallel) acquisition. Multi-phase contrast-enhanced abdominopelvic GRASP was performed during free-breathing (1.4×1.4×3.0mm(3) voxel size; 3:44min acquisition). Two dynamic datasets were retrospectively reconstructed by combining different numbers of sequentially acquired spokes into each dynamic frame: 110 spokes per frame for 25-s temporal resolution (serving as conventional MRU for clinical interpretation) and 8 spokes per frame for 1.7-s resolution. Using 1.7-s resolution images, ROIs were placed within bladder lesions and normal bladder wall, a femoral artery arterial input function was generated, and the Generalized Kinetic Model was applied., Results: Biopsy/cystectomy demonstrated 16 bladder tumors (13 stage≥T2, 3 stage≤T1) and 6 benign lesions. All lesions were well visualized using 25-s clinical multi-phase images. Using 1.7-s resolution images, K(trans) was significantly higher in tumors (0.38±0.24) than normal bladder (0.12±0.02=8, p<0.001) or benign lesions (0.15±0.04, p=0.033). Ratio between K(trans) of lesions and normal bladder was nearly double for tumors than benign lesions (4.3±3.4 vs. 2.2±1.6), and K(trans) was nearly double in stage≥T2 than stage≤T1 tumors (0.44±0.24 vs. 0.24±0.24), although these did not approach significance (p=0.180-0.209), possibly related to small sample size., Conclusion: GRASP allows simultaneous quantitative high temporal resolution perfusion of bladder lesions during clinical MRU examinations using only one contrast injection and without additional scan time., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Purpose: To prospectively assess radiation dose, image quality, and diagnostic performance of computed tomography (CT) urography for detection of urothelial carcinomas by performing reduced-dose scanning with iterative reconstruction (IR) compared with standard-dose scanning with filtered back projection (FBP)., Materials and Methods: The institutional review board approved the study with written informed patient consent. In total, 2163 patients at high risk for urothelial carcinomas randomly underwent standard-dose scanning with FBP (protocol A, 120 kVp for >80 kg body weight; protocol B, 100 kVp for 50-80 kg body weight) or reduced-dose scanning with IR (protocol C, 100 kVp for >80 kg body weight; protocol D, 80 kVp for 50-80 kg body weight). Objective image quality (signal-to-noise ratio and contrast-to-noise ratio) between the two groups with same weight range was measured for various regions of interest. Subjective image quality (visual image noise, artifact, ureter depiction, and overall image quality) and diagnostic accuracy (per lesion and per patient) were assessed with three- and five-point scores, respectively., Results: Size-specific dose estimate (protocol A vs protocol C, 24.2 mGy vs 19.2 mGy, respectively; protocol B vs protocol D,13.9 mGy vs 8.8 mGy, respectively) was significantly lower in reduced-dose scanning (P < .001 for both). There were significantly higher signal-to-noise and contrast-to-noise ratios in reduced-dose scanning, except for the abdominal aorta (P < .05 for all). There was no significant difference in subjective image quality, except for artifacts in protocols B and D (range, 4-5 vs 3-4; P < .05). Per-lesion diagnostic accuracy was 90.8% (89 of 98, protocol A), 91.3% (105 of 115, protocol B), 92.9% (79 of 85, protocol C), and 88.8% (111 of 125, protocol D)., Conclusion: Reduced-dose scanning with IR showed dose reduction and no significant difference of image quality in detection of urothelial carcinomas, except for some artifacts in 80-kVp scanning., ((©) RSNA, 2015.)

Intravenous urography has been widely used for the evaluation of upper tract urothelial carcinoma. However, computed tomography urography presently has a higher diagnostic accuracy for upper tract urothelial carcinoma (94.2-99.6%) than intravenous urography (80.8-84.9%), and has replaced intravenous urography as the first-line imaging test for investigating patients with a high risk of upper tract urothelial carcinoma. Although the detection rate for bladder tumors using standard computed tomography urography is not yet high enough to replace cystoscopy, the addition of a 60- to 80-s delayed scan after the administration of contrast material for the whole pelvis improves the detection rate. A drawback to computed tomography urography is the higher radiation dose of 15-35 mSv, compared with a mean effective dose of 5-10 mSv for intravenous urography. Among several approaches to reducing the radiation dose, the use of an iterative reconstruction algorithm is most likely to become an effective solution because of its simplicity. One advantage of computed tomography urography over intravenous urography is its ability to reliably differentiate between upper tract urothelial carcinoma and calculi or blood clots. Computed tomography urography also shows characteristic findings of other benign conditions. These findings, in combination with negative cytology, are very important diagnostic clues for avoiding an unnecessary nephroureterectomy. For the clinical staging, a recent study has reported the high diagnostic accuracy of computed tomography urography with respect to ≥pT3 tumors. The present review shows the current status of computed tomography urography for the evaluation of upper tract urothelial carcinoma., (© 2016 The Japanese Urological Association.)

Objective: To prospectively compare the detection of bladder cancer between low-dose scans with adaptive iterative dose reduction three dimensional projection (AIDR 3D) and routine-dose scans with filtered back projection (FBP) on the excretory phase (EP) in CT urography., Methods: 42 patients were included. Routine- and low-dose EP were performed in each patient. Routine-dose images were reconstructed with FBP, and low-dose images were reconstructed with AIDR 3D. Two radiologists scored confidence levels for the presence or absence of bladder cancer using a 5-point scale. The CT dose index of each EP was measured, and the dose reduction was calculated., Results: Sensitivity, specificity and accuracy were 86.4%, 95.0% and 90.5% on routine-dose scans and were 86.4%, 90.0% and 88.1% on low-dose scans, respectively. There was no significant difference (p; not significant, 1.00 and 1.00, respectively). The average CT dose index was 8.07 and 2.63 mGy on routine- and low-dose scans, and the ratio of dose reduction was 67.6%., Conclusion: The detection of bladder cancer on low-dose scans with AIDR 3D is almost equal to that on routine-dose scans with FBP on the EP, with nearly 70% dose reduction., Advances in Knowledge: Using AIDR 3D, the radiation dose may be reduced on the EP in CT urography for the detection of bladder cancer.

Objective: The purpose of this study was to evaluate the accuracy of our autoinitialized cascaded level set 3D segmentation system as compared with the World Health Organization (WHO) criteria and the Response Evaluation Criteria In Solid Tumors (RECIST) for estimation of treatment response of bladder cancer in CT urography., Materials and Methods: CT urograms before and after neoadjuvant chemo-therapy treatment were collected from 18 patients with muscle-invasive localized or locally advanced bladder cancers. The disease stage as determined on pathologic samples at cystectomy after chemotherapy was considered as reference standard of treatment response. Two radiologists measured the longest diameter and its perpendicular on the pre- and posttreatment scans. Full 3D contours for all tumors were manually outlined by one radiologist. The autoinitialized cascaded level set method was used to automatically extract 3D tumor boundary. The prediction accuracy of pT0 disease (complete response) at cystectomy was estimated by the manual, autoinitialized cascaded level set, WHO, and RECIST methods on the basis of the AUC., Results: The AUC for prediction of pT0 disease at cystectomy was 0.78 ± 0.11 for autoinitialized cascaded level set compared with 0.82 ± 0.10 for manual segmentation. The difference did not reach statistical significance (p = 0.67). The AUCs using RECIST criteria were 0.62 ± 0.16 and 0.71 ± 0.12 for the two radiologists, both lower than those of the two 3D methods. The AUCs using WHO criteria were 0.56 ± 0.15 and 0.60 ± 0.13 and thus were lower than all other methods., Conclusion: The pre- and posttreatment 3D volume change estimates obtained by the radiologist's manual outlines and the autoinitialized cascaded level set segmentation were more accurate for irregularly shaped tumors than were those based on RECIST and WHO criteria.

Aims and Background: To evaluate the diagnostic performance of computed tomography urography (CTU), we first compared it with cystoscopy and subsequently analyzed which CTU phase of acquisition has the highest diagnostic accuracy in identifying bladder cancer., Methods: In 2013, 177 patients underwent both cystoscopy and CTU. For all acquisition phases, we calculated sensitivity, specificity, diagnostic accuracy, and positive and negative predictive value (PPV and NPV, respectively). We also evaluated the Cohen κ coefficient., Results: Computed tomography urography sensitivity, specificity, diagnostic accuracy, PPV, and NPV were as follows: 96.3%, 86.4%, 92.8%, 92.9%, and 92.7%; concordance calculated with Cohen κ was good: 0.8413. The arterial acquisition phase showed the highest diagnostic accuracy, identifying 93.4% of all lesions., Conclusions: Computed tomography urography is an accurate examination for the diagnosis of bladder cancer, and the arterial acquisition phase provides the best diagnostic information.

Computed tomography urography (CTU) is a very detailed and powerful method of investigating the urinary tract, but an individual approach to each patient is recommended considering also the radiation dose. This article aims to present the initial experience from the diagnosis of urinary tract diseases and congenital variants in the anatomy of the urinary system using low-kV protocols. The image quality and patient dose in CTU were compared when replacing the standard 120-kV protocol with two different low-kV protocols. Totally, 91 patients (41 women and 55 men) with mean age 56.4 were studied with three different low-dose protocols. The patients underwent an unenhanced and excretory low-dose phases and standard corticomedullary and nephrographic phases. Effective dose was reduced by more than 65 % using the 100-kV protocol and by more than 76 % with introduction of 80-kV protocol. At the same time, patient images obtained with the new low-kV protocols maintained their diagnostic quality., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Purpose: The authors are developing a computer-aided detection system for bladder cancer on CT urography (CTU). In this study, the authors focused on developing a system for detecting masses fully or partially within the contrast-enhanced (C) region of the bladder., Methods: With IRB approval, a data set of 70 patients with biopsy-proven bladder lesions fully or partially immersed within the contrast-enhanced region (C region) of the bladder was collected for this study: 35 patients for the training set (39 malignant, 7 benign lesions) and 35 patients for the test set (49 malignant, 4 benign lesions). The bladder in the CTU images was automatically segmented using the authors' conjoint level set analysis and segmentation system, which they developed specifically to segment the bladder. A closed contour of the C region of the bladder was generated by maximum intensity projection using the property that the dependently layering contrast material in the bladder will be filled consistently to the same level along all CTU slices due to gravity. Potential lesion candidates within the C region contour were found using the authors' Straightened Periphery ANalysis (SPAN) method. SPAN transforms a bladder wall to a straightened thickness profile, marks suspicious pixels on the profile, and clusters them into regions of interest to identify potential lesion candidates. The candidate regions were automatically segmented using the authors' autoinitialized cascaded level set segmentation method. Twenty-three morphological features were automatically extracted from the segmented lesions. The training set was used to determine the best subset of these features using simplex optimization with the leave-one-out case method. A linear discriminant classifier was designed for the classification of bladder lesions and false positives. The detection performance was evaluated on the independent test set by free-response receiver operating characteristic analysis., Results: At the prescreening step, the authors' system achieved 84.4% sensitivity with an average of 4.3 false positives per case (FPs/case) for the training set, and 84.9% sensitivity with 5.4 FPs/case for the test set. After linear discriminant analysis (LDA) classification with the selected features, the FP rate improved to 2.5 FPs/case for the training set, and 4.3 FPs/case for the test set without missing additional true lesions. By varying the threshold for the LDA scores, at 2.5 FPs/case, the sensitivities were 84.4% and 81.1% for the training and test sets, respectively. At 1.7 FPs/case, the sensitivities decreased to 77.8% and 75.5%, respectively., Conclusions: The results demonstrate the feasibility of the authors' method for detection of bladder lesions fully or partially immersed in the contrast-enhanced region of CTU.

Objective: The aim of this study was to compare split-bolus computed tomography urography (CTU), magnetic resonance urography (MRU) and flexible cystoscopy in patients with macroscopic haematuria regarding the diagnosis of bladder tumours., Materials and Methods: In this prospective study, 150 patients underwent CTU, MRU and flexible cystoscopy. Two uroradiologists individually reviewed the images without any clinical information, using a questionnaire. Patient records and pathology reports were also reviewed., Results: At flexible cystoscopy, MRU and CTU, 32, 19 and 15 bladder lesions were identified, respectively. Histopathology showed that 13 of the 29 biopsied lesions were transitional cell carcinomas. Compared with the histopathology, the sensitivity and specificity for detection of tumours by CTU and MRU were 61.5% and 94.9%, and 79.9% and 93.4%, respectively. False-positive detection of bladder tumours, compared with histopathology, was reported in seven CTUs and nine MRUs, whereas the number of false-negative findings was five for CTUs and three for MRUs., Conclusions: Split-bolus CTU or MRU cannot replace cystoscopy in cases of macroscopic haematuria. MRU has a higher sensitivity than split-bolus CTU, and is a potential alternative to flexible cystoscopy. Patients with a low risk of bladder cancer may forgo flexible cystoscopy if a bladder tumour is identified by either CTU or MRU, and proceed straight to transuretheral resection of the bladder.

Purpose: To determine the yield of CT urography (CTU) in the surveillance of patients with bladder cancer following cystectomy., Materials and Methods: In this IRB-approved, HIPAA-compliant, retrospective study of 5,404 CT urograms performed at our institution between March 2000 and February 2011, 225 CT urograms were performed in 105 patients [79 men, 26 women; mean age 65 years (43-85)] following cystectomy for bladder cancer. Median follow-up after cystectomy was 63 months (range 1-234), median time between cystectomy and CTU was 39 months (range 0-229), median follow-up after CTU was 34 months (range 1-111). CTU examinations were reviewed by two radiologists in consensus and findings were categorized into those related to surgery, locoregional recurrence, metastases, or metachronous upper tract urothelial tumor (UTT)., Findings: Findings were present in 69 (65.7 %) of 105 patients, including findings related to surgery in 60 (57.1 %) patients, locoregional recurrence or metastatic disease in 21 (20 %) patients, and UTT in 3 (2.9 %) patients. Of surgery-related findings, hydronephrosis (23/105, 21.9 %) and parastomal hernia (17/105, 16.2 %) were the most common findings. Visceral metastases (16/105, 15.2 %) and lymph node metastases (13/105, 12.4 %) were the most common manifestations of recurrent disease., Conclusion: CTU findings in the surveillance of patients with bladder cancer after cystectomy are common and include those related to surgery, spread of the disease, and metachronous tumors. Our study supports current published guidelines on the use of CTU in these patients.

Objective: Our objective was to evaluate the sensitivity, specificity, predictive value, and accuracy of computed tomographic urography for the detection of bladder tumors in patients with microscopic hematuria., Material and Methods: Patients with microscopic hematuria initially evaluated with computed tomography and cystoscopy from January 2006 to December 2009 were evaluated. Computed tomography detecting a bladder lesion suspicious of malignancy was considered positive. Cystoscopy was classified as positive when a lesion requiring biopsy or resection was found. Performance characteristics of computed tomography were determined by comparing with cystoscopic and pathological findings., Results: A total of 112 patients were eligible for analysis. Seven tumors were found on cystoscopy; of these, 2 were correctly diagnosed by computed tomography and 5 were missed. An additional case was considered erroneously positive. The results are a sensitivity of 29%, specificity of 99%, positive predictive value of 67%, negative predictive value of 95%, and accuracy of 95%., Conclusions: Although computed tomography has a high specificity its sensitivity is limited. For this reason conventional cystoscopy should be considered the standard for bladder evaluation of patients with microscopic hematuria., (Copyright © 2012 AEU. Published by Elsevier Espana. All rights reserved.)

Rationale and Objectives: To develop a computerized system for segmentation of bladder lesions on computed tomography urography (CTU) scans for detection and characterization of bladder cancer., Materials and Methods: We have developed an auto-initialized cascaded level set method to perform bladder lesion segmentation. The segmentation performance was evaluated on a preliminary dataset including 28 CTU scans from 28 patients collected retrospectively with institutional review board approval. The bladders were partially filled with intravenous contrast material. The lesions were located fully or partially within the contrast-enhanced area or in the non-contrast-enhanced area of the bladder. An experienced abdominal radiologist marked 28 lesions (14 malignant and 14 benign) with bounding boxes that served as input to the automated segmentation system and assigned a difficulty rating on a scale of 1 to 5 (5 = most subtle) to each lesion. The contours from automated segmentation were compared to three-dimensional contours manually drawn by the radiologist. Three performance metric measures were used for comparison. In addition, the automated segmentation quality was assessed by an expert panel of two experienced radiologists, who provided quality ratings of the contours on a scale from 1 to 10 (10 = excellent)., Results: The average volume intersection ratio, the average absolute volume error, and the average distance measure were 67.2 ± 16.9%, 27.3 ± 26.9%, and 2.89 ± 1.69 mm, respectively. Of the 28 segmentations, 18 were given quality ratings of 8 or above. The average rating was 7.9 ± 1.5. The average quality ratings for lesions with difficulty ratings of 1, 2, 3, and 4 were 8.8 ± 0.9, 7.9 ± 1.8, 7.4 ± 0.9, and 6.6 ± 1.5, respectively., Conclusion: Our preliminary study demonstrates the feasibility of using the three-dimensional level set method for segmenting bladder lesions in CTU scans., (Copyright © 2013 AUR. Published by Elsevier Inc. All rights reserved.)

Purpose: To prospectively evaluate the feasibility of dual-energy (DE) split-bolus CT-urography (CTU) and the quality of virtual non-enhanced images (VNEI) and DE combined nephrographic-excretory phase images (CNEPI), and to estimate radiation dose reduction if true non-enhanced images (TNEI) could be omitted., Patients and Methods: Between August and September 2011, 30 consecutive patients with confirmed or suspected urothelial cancer or with hematuria underwent DE CT. Single-energy TNEI and DE CNEPI were obtained. VNEI was reconstructed from CNEPI. Image quality of CNEPI and VNEI was evaluated using a 5-point scale. The attenuation of urine in the bladder on TNEI and VNEI was measured. The CT dose index volume (CTDI (vol)) of the two scans was recorded., Results: The mean image quality score of CNEPI and VNEI was 4.7 and 3.3, respectively. The mean differences in urine attenuation between VNEI and TNEI were 14±15 [SD] and -16±29 in the anterior and posterior parts of the bladder, respectively. The mean CTDI (vol) for TNEI and CNEPI was 11.8 and 10.9 mGy, respectively. Omission of TNEI could reduce the total radiation dose by 52%., Conclusion: DE split-bolus CTU is technically feasible and can reduce radiation exposure; however, an additional TNEI scan is necessary when the VNEI quality is poor or quantitative evaluation of urine attenuation is required., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Purpose: To compare contrast material-enhanced computed tomographic (CT) urography 60 seconds after injection of contrast material (urothelial phase [UP]) after intravenous administration of a diuretic with the standard 5-minute delayed excretory phase (EP) in a high-risk population for upper tract tumors., Materials and Methods: Institutional review board approval and informed consent were obtained. Eighty CT urographic examinations in 77 patients known to have or at high risk for urothelial malignancy were included. After intravenous administration of a diuretic, dual-phase CT urography was performed at 60 seconds (UP) and 5 minutes (EP) after intravenous administration of contrast material. Two experienced abdominal radiologists independently interpreted each phase more than 1 month apart to minimize recall bias. Urinary tract distention and location and size of all lesions suspected of being urothelial tumors were recorded. Standard of reference was obtained from prospective study interpretation and surgical histopathologic findings. Generalized estimating equations for logistic regression were used to compare performance measures and adjust for the correlation of repeated measures within patients., Results: There were 23 upper and 61 lower urinary tract tumors confirmed in 15 and 32 patients, respectively. For detection of bladder tumors, there was higher sensitivity for the UP than the EP (89.3% [109 of 122] vs 70.5% [86 of 122], respectively; P<.0001). For detection of upper tract tumors, there was higher sensitivity for the UP than the EP (82.6% [38 of 46] vs 69.6% [32 of 46], respectively; P=.0194). Distention of all upper urinary tract segments was better during the EP than the UP (P<.0001)., Conclusion: UP CT urography after injection of a diuretic has a higher lesion detection rate than the EP for both upper and lower urinary tract tumors, which suggests its possible use as a single-phase protocol for evaluation of the entire urinary tract in patients at high risk for urothelial tumors., (© RSNA, 2012.)

Objective: To assess multidetector-row computed tomographic (MDCT) urography for detection of recurrence of bladder tumor after transurethral resection (TUR), and to assess significance of the MDCT findings like urothelial enhancement or thickening as a recurrence., Methods: A total of 216 MDCT urography examinations were performed for 100 patients undergoing follow-up after TURs were reviewed by 2 radiologists, according to MDCT findings (urothelial enhancement or thickening) and location (TUR site or distant sites of transitional cell carcinoma). Multidetector-row CT urography was confirmed by cystoscopy and urine cytologic examination. Analyses of per-MDCT urography and per-lesion basis were performed, assessing receiver operating characteristic analysis for combining excretory phases to noncontrast and portal venous phases., Results: Fifty-two MDCT findings were positive, and 164 MDCT findings were negative. Of the 52 positive MDCT urography, 19 were true positive 33 were false positive. Of the 60 separate lesions, 25 lesions were true positive. Both urothelial enhancement and thickening were revealed in 19 lesions, urothelial enhancement in 4 lesions, and urothelial thickenings in 2 lesions. Nineteen lesions were revealed in TUR site, and 6 lesions were revealed in distant site of transitional cell carcinoma. For MDCT urography combining excretory phases to noncontrast and portal venous phases, a substantial agreement between radiologists was revealed (area under the curve; 0.910 ± 0.035, 0.749 ± 0.055; 8.3%; kappa score of 0.65)., Conclusions: Multidetector-row CT urography has efficacy in detecting recurrence of bladder tumor in patients undergoing follow-up after TUR.

Background: Although CT urography (CTU) is widely used for the evaluation of the entire urinary tract, the most important drawback is the radiation exposure., Purpose: To evaluate the effect of a noise reduction filter (NRF) using a phantom and to quantitatively and qualitatively compare excretory phase (EP) images using a low noise index (NI) with those using a high NI and postprocessing NRF (pNRF)., Material and Methods: Each NI value was defined for a slice thickness of 5 mm, and reconstructed images with a slice thickness of 1.25 mm were assessed. Sixty patients who were at high risk of developing bladder tumors (BT) were divided into two groups according to whether their EP images were obtained using an NI of 9.88 (29 patients; group A) or an NI of 20 and pNRF (31 patients; group B). The CT dose index volume (CTDI(vol)) and the contrast-to-noise ratio (CNR) of the bladder with respect to the anterior pelvic fat were compared in both groups. Qualitative assessment of the urinary bladder for image noise, sharpness, streak artifacts, homogeneity, and the conspicuity of polypoid or sessile-shaped BTs with a short-axis diameter greater than 10 mm was performed using a 3-point scale., Results: The phantom study showed noise reduction of approximately 40% and 76% dose reduction between group A and group B. CTDI(vol) demonstrated a 73% reduction in group B (4.6 ± 1.1 mGy) compared with group A (16.9 ± 3.4 mGy). The CNR value was not significantly different (P = 0.60) between group A (16.1 ± 5.1) and group B (16.6 ± 7.6). Although group A was superior (P < 0.01) to group B with regard to image noise, other qualitative analyses did not show significant differences., Conclusion: EP images using a high NI and pNRF were quantitatively and qualitatively comparable to those using a low NI, except with regard to image noise.

The objective of this review article is to learn how to recognize anatomic variants and benign entities that mimic bladder cancer at computed tomography (CT) urography. Building on recent data that suggest that CT urography can be used to diagnose bladder cancer, recognition of anatomic variants and benign entities will help improve radiologists' ability to diagnose bladder cancer.

Objective: The purpose of this study was to determine the positive predictive value of CT urography in the diagnosis of upper tract urothelial malignancies., Materials and Methods: Retrospective review of the records of patients who underwent 2,602 CT urographic examinations revealed that 81 (3%) examinations of 77 patients had findings suggesting upper tract urothelial cancer. Two radiologists in consensus categorized the findings as large masses (> 5 mm), small masses (≤ 5 mm), or urothelial thickening. The positive predictive value of CT urography was determined with the findings at pathologic examination (n = 42), followup imaging (n = 29), or clinical follow-up alone (n = 5). One patient with insufficient follow-up information was excluded. The effects of age, sex, indication for examination, imaging appearance, and urine cytology were analyzed with the Fisher's exact test or Student's t test. Multivariate logistic regression analysis was used to generate a model for predicting the probability of the presence of upper tract urothelial cancer in patients with positive CT urographic examinations., Results: The positive predictive value of CT urography for upper tract urothelial cancer was 53% (40/76) overall, 83% (29/35) for large masses, 0% (0/17) for small masses, and 46% (11/24) for urothelial thickening. Imaging appearance, urine cytology, and age were significant univariate predictors (p < 0.05) of the presence of upper tract urothelial cancer in patients with positive CT urographic examinations. The independent variables most likely associated with upper tract urothelial cancer were urine cytology (odds ratio, 60.0; 95% CI, 5.5-653.7) and imaging appearance (odds ratio, 24.4; 95% CI, 3.0-201.9) after adjusting for age and clinical indication., Conclusion: The positive predictive value of CT urography for upper tract urothelial cancer is moderate because benign findings mimic cancer. Positive findings on a CT urogram are more likely to indicate cancer in the setting of large masses or positive urine cytology.

Purpose: This study sought to assess the diagnostic accuracy of 64-slice computed tomography urography (CTU) in evaluation of the urinary tract., Materials and Methods: A total of 322 CTU procedures were carried out in 317 consecutive patients (mean age 64.4 years). The findings were compared with previous and subsequent patient workup considering both laboratory and imaging studies, such as urine cytology, abdominal ultrasound and CT, cystoscopy, retrograde pyelography, surgery and pathology., Results: Out of 322 CTU examinations, 169 showed significant urinary tract changes, whereas 153 revealed no urinary disease, in good agreement with the follow-up. In particular, in bladder evaluation, for which we have a direct comparison with cystoscopy in 125 patients, we calculated a CTU sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy of 85%, 94%, 92%, 89% and 90%, respectively., Conclusions: CTU was accurate for urinary tract evaluation, but it cannot replace cystoscopy in patients in whom a malignant bladder disease is suspected.

Objective: The purpose of this article is to review the epidemiology, staging, and treatment of bladder cancer; to discuss the role of MDCT urography for the evaluation of patients with known or suspected bladder cancer; and to address the role of MDCT urography in patients who require follow-up imaging after a diagnosis of bladder cancer has been made., Conclusion: MDCT urography now has a large role in the evaluation of patients with known and suspected bladder cancer. However, its precise role has not been established. Because many bladder neoplasms will not be detected by MDCT urography and more research is needed to determine the optimal technique for diagnosing bladder cancer, we think that MDCT urography cannot replace cystoscopy at present.

Aim: To evaluate and compare the diagnostic accuracy of multidetector computed tomography urography (CTU) and ultrasonography (US) for diagnosing bladder cancer., Materials and Methods: A consecutive series of 143 patients over 40-years of age, presenting with macroscopic haematuria and without urinary tract infection underwent same-day CTU, US, and flexible cystoscopy. CTU and US were independently rated on a five-point scale for the presence of bladder cancer without knowledge of the reference standard of flexible or rigid cystoscopy and/or biopsy results. Diagnostic accuracy was assessed by receiver operating characteristic (ROC) analysis and likelihood ratios., Results: For CTU, a rating of 5 (definitely tumour) was highly specific for bladder cancer (96.5%, 95%CI: 91.3-99%), effectively confirming diagnosis (positive likelihood ratio 25.6, 95%CI: 9.7-67.4). For US, specificity was also high (94.7%, 95%CI: 88.9-98%) with a positive likelihood ratio of 13.1 (95%CI: 5.8-29.6). Sensitivity at this rating was substantially higher for CTU (89.7%, 95%CI: 72.7-97.8%) than US (69%, 95%CI: 49.2-84.7%). Standardized partial area (Az) under the ROC curve between 95-100% specificity, representing the average sensitivity in this range, was significantly greater (0.88 versus 0.61, p<0.05) for CTU than US., Conclusion: The specificities of CTU and US for the diagnosis of bladder cancer were similar, but CTU was more sensitive. Although the sensitivity of CTU was not high enough to replace flexible cystoscopy in the diagnostic pathway, the high specificity enables direct referral to rigid cystoscopy, bypassing flexible cystoscopy and expediting diagnosis and treatment in those patients testing positive.

Purpose: To evaluate the performance characteristics of computed tomographic (CT) urography for the detection of bladder cancer in patients at risk for the disease., Materials and Methods: Institutional review board approval was obtained for this retrospective HIPAA-compliant review of medical records of 2600 consecutive patients undergoing CT urography. Of these, 838 CT urograms in 779 patients (449 men, mean age of 62 years, range of 27-92 years; 330 women, mean age of 56 years, range of 18-86 years) evaluated for hematuria or a history of urothelial cancer, who had undergone cystoscopy within 6 months of the CT urogram, were included in the study. Clinical reports of CT urograms containing a bladder lesion interpreted as suspicious for malignancy were classified as positive. All others were classified as negative. Cystoscopy reports were classified as positive if a lesion underwent biopsy or was resected or negative if no lesion was detected. Performance characteristics for both CT urography and cystoscopy were determined by using pathologic findings or clinical follow-up as the reference standard. Ninety-five percent confidence intervals were estimated for each test characteristic., Results: The overall sensitivity, specificity, accuracy, positive predictive value, and negative predictive value (NPV) for bladder cancer detection were 79% (117 of 149), 94% (649 of 689), 91% (766 of 838), 75% (117 of 157), and 95% (649 of 681) for CT urography and 95% (142 of 149), 92% (634 of 689), 93% (776 of 838), 72% (142 of 197), and 99% (634 of 641) for cystoscopy. The NPV of CT urography was higher in patients evaluated for hematuria alone (98%, 589 of 603). However, the accuracy of CT urography was considerably lower in patients with a prior urothelial malignancy (78%, 123 of 158)., Conclusion: CT urography is an accurate noninvasive test for detecting bladder cancer in patients at risk for the disease. The high NPV of CT urography in patients with hematuria may obviate cystoscopy in selected patients., ((c) RSNA, 2008.)

Purpose: We determined the efficiency of routine excretory urography for detecting tumor recurrence in the upper urinary tract after cystectomy and urinary diversion for bladder cancer., Materials and Methods: We evaluated 322 patients who underwent cystectomy and urinary diversion, and had undergone routine followup, including regular excretory urography 1, 2, 3, 5, 7 and 10 years after cystectomy., Results: Upper urinary tract recurrence was found in 15 of the 322 patients (4.7%) patients. Eight of 15 cases were detected by routine excretory urography, resulting in a low efficiency of 0.75% (8 of 1,064 studies) for this method. The remaining 7 recurrences were detected as a result of symptoms such as macrohematuria or flank pain occurring between routine followup examinations. Patients were at up to 10 times higher risk for recurrence in the upper urinary tract if they had positive distal ureteral resection margins or a history of upper urinary tract tumors. Although the incidence of recurrence in the upper urinary tract increased 1.8-fold in patients with pTa/pT1 tumors, it remained relatively low at 8.4%., Conclusions: The incidence of recurrence in the upper urinary tract a median of 49 months (range 12 to 220) after cystectomy for transitional cell carcinoma was 4.7%. Because only half of these cases were detected by routine excretory urography, this should be limited to patients at high risk with a history of upper urinary tract tumors or positive ureteral margins. In the future other techniques, eg cytology of voided urine or new markers, should be evaluated to replace excretory urography for routine followup of patients after cystectomy for transitional cell carcinoma of the bladder.

Objective: Our purpose was to evaluate the utility of CT urography performed using a split contrast bolus that yields synchronous nephrographic and excretory phase enhancement., Materials and Methods: Five hundred consecutive patients referred for evaluation of possible urinary tract abnormalities (327 for painless hematuria) underwent CT urography with unenhanced scanning of the abdomen and pelvis and scanning during concurrent nephrographic and excretory phase enhancement produced by administration of a split contrast bolus. The enhanced abdomen scan was obtained with abdominal compression; the enhanced pelvis scan was obtained after release of compression. Findings from axial sections and coronal maximum intensity projections were correlated with clinical follow-up and, as available, with laboratory and other imaging studies including cystoscopy, ureteroscopy, urine cytology, surgery, and pathology. Follow-up management for each patient was determined by the clinical judgment of the referring physician., Results: CT urography identified 100% of pathologically confirmed renal cell carcinomas (n = 10) and uroepithelial malignancies involving the renal collecting system or ureter (n = 8). An additional nine renal masses were identified for which no pathologic proof has yet been obtained, including eight subcentimeter solid renal masses and one multiloculated lesion. Fourteen of 19 confirmed cases of uroepithelial neoplasm involving the bladder were identified. CT urography yielded one false-positive for bladder tumor, two false-positives for ureteral tumor, and one patient with a bladder mass who refused further evaluation. CT urography yielded sensitivity and specificity of 100% and 99% and 74% and 99% and positive predictive value and negative predictive value of 80% and 100% and 93% and 99% for the renal collecting system and ureter and bladder, respectively. CT urography was ineffective in identifying 11 cases of noninfectious cystitis. CT urography also depicted numerous other congenital and acquired abnormalities of the urinary tract., Conclusion: Split-bolus MDCT urography detected all proven cases of tumors of the upper urinary tract, yielding high sensitivity and specificity. The split-bolus technique has the potential to reduce both radiation dose and the number of images generated by MDCT urography.

Bladder cancer is a heterogeneous and frequently multifocal disease with a variable clinical course. The management of bladder cancer is therefore challenging and complicated. CT and MR imaging have replaced the traditional excretory urography and are emerging as the imaging modalities of choice for work-up of patients who have bladder cancer. Imaging provides essential diagnostic information for detection, staging, and post-treatment follow-up of bladder cancer.

Objective: 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., Materials and Methods: 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., Results: 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)., Conclusion: 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.

Radiologists, especially uroradiologists, must retain abreast of rapid developments in urologic therapy and operative techniques in order to critically assess postoperative changes. Part 2 of this review will cover therapy and postoperative evaluation in bladder surgery, surgery in prostate cancer, and retroperitoneal disease associated with testicular tumors. Using the appropriate modality at the appropriate time during the postoperative course is discussed. A variety of alternatives are available to perform urinary diversion after radical cystectomy. Knowledge of operative techniques and postoperative anatomy are mandatory for interpretation of postoperative radiologic findings.

The bladder's cancer is frequent in West Africa. Urinary schistosomiasis endemicity helps to explain this high incidence. It is a pathology of late diagnosis, little or badly explored by imaging. Through a retrospective survey of 71 patients' files aged in average of 51.7 years, all having a bladder's tumour which is clinically shown by an haematuria, the major symptom, often by a pelvic volume, and who have all gone through an abdominal echography and/or intravenous urography (IVU) and/or retrograde urethrocystography (UCR), we have tried to point out the role of imaging in the caring of this pathology in our working context. Imaging, with a 98.5% sensibility for sonography and 100% for IVU, took part in all the cases to the diagnosis, to the search of urinary signs of reflux, associated signs authorizing a diagnostic orientation, but was excluded from the evolutive follow-up due to the poverty of our populations. So, despite some limits specific to the survey, particularly the absence of historadiological comparison for all the files, echography and IVU with cystography have always led to malignancy diagnosis. Therefore they should be requested for any patient consulting for haematuria.

A new technique of urinary tracts visualization--magnetoresonance urography (MRU)--for a year (2000) was applied in examination of 25 patients aged 17 to 63 years with ureteral concrements (n = 11), ureteropelvic stenosis (n = 10), ureteral stenosis (n = 2), urinary bladder tumor (n = 1), Ormond's disease (n = 1). MRU provides the same information about the obstruction and dilatation of the urinary tracts as excretory urography (EU). In cases of EU contraindication (allergy, renal failure) or lack of contrast substance excretion, MRU allows to avoid additional invasive diagnostic procedures. It also enables visualization of non-dilated urinary tracts in medicinal polyuria. Non-invasiveness, no need to contrast, absence of radiation load open wide perspectives for MRU application in various groups of patients including pregnant women.

Purpose: To evaluate the feasibility and clinical utility of Gd-BOPTA enhanced excretory magnetic resonance urography without additional administration of diuretics in correlation with conventional urography., Method: 15 preoperative patients with pelvic tumors were examined at 1.5 T using a breath-hold high-resolution 3D-FLASH sequence during first-pass as well as 5, 10, 15 minutes after i.v. injection of 0.05 mmol/kg BW Gd-BOPTA (MultiHance) without administration of diuretics. Post-processed coronal and multiplanar MIP reconstructions were compared to conventional excretory urography with regard to morphologic accuracy, anatomic variability, filling defects, cause and level of obstruction or compression, tumor visibility, and time-effectiveness by two independent radiologists., Results: Visualization of the urinary tract by MRU was comparable to conventional excretory urography in 14 of 15 cases. Caliceal fornices were better delineated on conventional urographies, whereas MRU was considered superior in the assessment of the inferior ureter sections, the urinary bladder and obstructive tumors, whose extents could be clearly marked out. Examination times of both techniques were comparable., Conclusion: These first results show that non-diuretic Gd-BOPTA enhanced MRU is comparable to conventional excretory urography for the preoperative diagnosis of pelvic tumors. Further improvements of this technique seem possible by optimization of examination intervals and injection doses.

Objective: To assess the need for and the efficacy of intravenous urography in the detection of a synchronous upper tract urothelial tumor (UTUT) in patients with primary bladder tumor., Materials: Between 1986 and 1996, 793 patients were diagnosed as having primary tumor of the bladder with pathological confirmation of transitional cell carcinoma. All patients underwent intravenous urography prior to transurethral resection. The mean age of the patients was 66.4 years, and 87.7% of them were male. Of these patients, 72% had superficial tumors, while the remaining 28% had infiltrative tumors. Histological classification of the tumors was: grade I, 10%; grade II, 45%, and grade III, 45%. A chi(2) test was used for statistical analysis., Results: The incidence of upper tract urothelial tumors was 1.1% (9 patients), although intravenous urography only diagnosed 6 cases (0.7%). No differences were seen between patients with or without UTUT with regard to histological grade (p = 0.7), multiple bladder tumors (p = 0.7) and tumor infiltration (p = 0.9). In 5.8% of the patients an unsuspected associated pathology was detected which required treatment in 1.4% of the cases., Conclusions: Due to the low incidence of UTUT (1.1%) in our series and to the fact that intravenous urography was effective in diagnosing synchronous UTUT in only 66.6% of cases, we do not consider that this procedure should be routinely performed in the diagnostic workup of patients with primary transitional cell tumor of the bladder.

Rationale and Objectives: The authors prospectively explored the efficacy of using prone positioning during intravenous urography to improve diagnostic visualization and eliminate the need for retrograde pyeloureterography in patients with no obstruction but with hematuria, history of urothelial tumor, or abnormal results of urine cytology., Materials and Methods: Prone radiography was added to the usual intravenous urography protocol in 510 patients (347 men, 163 women) without urinary tract obstruction. Interpretations of intravenous urograms and recommendations for retrograde pyeloureterography were made before and after evaluation of the prone image., Results: Confidence in the urographic interpretation was improved with acquisition of the prone radiograph in 100 of 510 patients (19.6%) (95% confidence interval, 82.1, 118). Retrograde pyeloureterography was obviated in 46 of 510 patients (9.0%) (95% confidence interval, 33.1, 58.9). The prone image was most helpful in evaluating the distal ureters (sacral and pelvic segments)., Conclusion: Prone patient positioning during intravenous urography is useful when complete visualization of the upper urinary tract is desirable. Obtaining the additional image is cost-effective, even when only a few retrograde pyeloureterography studies are obviated.

Purpose: To compare the diagnostic value of intravenous urography (IVU), ultrasound (US) and their combination in detecting upper urinary tract malignancies in patients with haematuria., Materials and Methods: In a prospective study, 360 consecutive patients who consulted the urologist for haematuria without renal colic were scheduled for IVU and US on the same day. The two procedures were performed by two different radiologists and reported independently. Histology or clinical follow-up of one year served as the gold standard., Results: 63 patients dropped out. Of the remaining 297 patients, 9 (3%) had a malignancy in the upper urinary tract. Sensitivity and specificity with regard to the upper urinary tract pathology were 67% and 91% for IVU and 56% and 94% for US, respectively. For both techniques combined this was 79% and 88%, respectively., Conclusion: An acceptable sensitivity for detecting upper urinary tract malignancies is obtained only by combining IVU and US.

The authors describe the technique of RARE sequences (Hennig, 1986) and their hydrographic application to urinary imaging, RARE urography. Heavily T2-weighted non-tomographic images of the urinary tract are obtained in less than 30 seconds, without contrast medium or ionizing radiation. The whole urinary tract is visualised on one image with a spatial resolution superior to that of sonography. The semiology of RARE urography is similar to that of the intravenous pyelogram. Silent kidneys are also visualised.

Hematuria is defined as the presence of blood in urine. Its site of origin can be in any point of the urinary tract. Its discovery leads to clinical, biological and radiological investigations. The causes of hematuria are dominated, in terms of frequency, by urinary infection and lithiasis. The risk of associated lesions, especially of a tumor, must lead to regarding them as excluding diagnoses. Besides the so-called "medical" hematurias of glomerular origin (hematuria with proteinuria and cylinder casts) and hematurias occurring during a first episode of cystitis in women, the radiological exploration of "surgical" hematuria is systematic and always begins with an IVP. When the IVP is normal, a cystoscopy is most often made. The other radiological examinations (CT, Doppler ultrasound) are performed only according to the findings of IVP and cystoscopy. Arteriography combined with renal phlebography is indicated if the assessment is negative in case of recurrent hematuria or of massive hematuria. It is mainly aimed at detecting a vascular malformation. When this exploration is completed, an etiology is found is about 90% of all cases.