Metal stent for the ureteral stricture after surgery and/or radiation treatment for malignancy.

BACKGROUND: To assess the efficacy and safety of self-expanding metal ureteral stent for the stricture following surgery and/or radiation for malignancy. METHODS: We performed 36 metal ureteral stent insertion procedures (32 patients) between May 2019 and June 2020. The main inclusion criterion was the patients with ureteral stricture due to surgery and/or radiation treatment for malignancy. The diagnosis of stricture was ascertained by history and radiographic imaging. The etiologies underlying the strictures were: surgery and/or radiation therapy for cervical and rectal cancer, surgery for ovarian cancer. The primary outcome was the stent patency rate, and the secondary outcomes were the postoperative complications and glomerular filtration rate (GFR). Stent patency was defined as stent in situ without evident migration, unanticipated stent exchange or recurrent ureteral obstruction. Cost analysis was calculated from stent cost, anesthesia cost and operating room fee. RESULTS: The pre-metallic stent GFR was 22.53 ± 6.55 mL/min/1.73 m2. Eight patients were on double-J stents before insertion of metallic stents. The total annual cost of per patient in our study was $10,600.2 US dollars (range $9394.4-$33,527.4 US dollars). During a median follow-up time of 16 months (range 8-21 months), 27 cases (31 sides, 84%) remained stent patency. Twelve patients died from their primary malignancy carrying a patency stent. Stent migration was observed in 4 patients within 10 months after insertion. Ectopic stents were endoscopically removed and replaced successfully. Three stents were occluded, and no encrustation was seen in our study. Three and four patients had postoperative fever and gross hematuria, respectively. Infection was observed in 2 cases, mandating antibiotics therapy. In addition, postoperative volume of hydronephrosis postoperatively was significantly reduced compared with preoperation (54.18 ± 15.42 vs 23.92 ± 8.3, P = 0.019). However, no statistically significant differences regarding GFR, creatinine levels, blood urea nitrogen and hemoglobin existed between preoperation and last follow-up. CONCLUSIONS: The current study demonstrated that metal ureteral stent is effective and safe in the treatment of stricture following surgery and/or radiation therapy for malignant cancer. Patients hydronephrosis could be improved by the stent placement.

Predictive value of ureteral wall thickness (UWT) assessment on the success of internal ureteral stent insertion in cases with obstructing ureteral calculi.

To evaluate the possible role of ureteral wall thickness (UWT) assessment in the prediction of the success for stent placement in cases with obstructing ureteric stones. 227 adult patients with a single unilateral obstructing ureteral stone requiring internal ureteral stent placement were included. In addition to stone size, the ureteric wall thickness at the impacted stone site and the degree of hydronephrosis were also assigned on CT images. Patients were divided into two subgroups: Group 1: patients in whom internal ureteral stent could not be passed beyond the stone and Group 2: patients in whom an internal ureteral stent was passed successfully. The possible relationship between the UWT values and the success of stent placement, degree of hydronephrosis were comparatively evaluated. The majority of the stones were located in the proximal ureter in Group 1 and the degree of hydronephrosis was also higher in these cases. Moreover, while the mean value of UWT calculated on CT images was 4.3 ± 0.9 mm in Group 1, this value was noted to be 2.5 ± 0.8 mm in cases of group 2. A cutoff UWT value of 3.35 mm was highly predictive for the stent insertion and cases with higher values required additional procedures or percutaneous nephrostomy tube placement. UWT value calculated at the obstructing stone site was found to be predictive enough for the likelihood of internal ureteral stent passage with high sensitivity and specificity. This evaluation may enable the urologist to make the best decision for urinary diversion in such cases.

Hydronephrosis severity score: an objective assessment of hydronephrosis severity in children-a preliminary report.

The main challenge in the management of antenatally diagnosed hydronephrosis and ureteropelvic junction obstruction (UPJO) is to differentiate the one that is likely to resolve from the pathological one. In this study, a new hydronephrosis severity score (HSS), combining ultrasonographic and renographic parameters, has been developed. Hydronephrosis severity score was analyzed with regard to its usefulness in assessing the severity of UPJO, postoperative resolution, and interobserver reliability. METHODS: Hydronephrosis severity score was devised with three parameters: differential renal function (DRF), drainage curve pattern, and ultrasonogram grade (Table 1). Hydronephrosis severity score ranges were divided as 0-4, mild; 5-8, moderate; and 9-12, severe and compared with clinical outcomes (resolution, persistence, or surgical intervention) by retrospective case record review of children with unilateral UPJO. Among those who underwent surgery, surgical outcomes were compared with changes in HSS at 6-month follow-up. Hydronephrosis severity score was computed by three observers, and interobserver variability was calculated. RESULTS: A total of 125 case records (male:female = 93:32; right:left = 44:81) were analyzed. Among the patients analyzed, none (0/59) with HSS 0-4 warranted surgery, whereas 1 of 35 patients with HSS 5-8 underwent surgery, and all (31/31) with HSS 9-12 underwent surgery (P = 0.001). Overall, hydronephrosis resolved in 65, persisted in 28, and required surgery in 32 patients. Mean (standard deviation) HSS was 2.1 (0.75) in whom it resolved, 6.2 (0.78) in whom it persisted, and 10.2 (0.79) in those who underwent surgery (analysis of variance P = 0.001). Among those who underwent surgery, a better recovery of HSS was noted in younger infants (aged 2-5 months) with higher pre-operative DRF. There was 94.4% median agreement between radiologists and the surgeon (kappa 0.851), indicating a very good interobserver agreement. DISCUSSION: Loss of DRF on progressive renograms remains the accepted criterion of significant UPJO although the lost function does not always recover after pyeloplasty. Newer scoring systems keep evolving to predict the need for surgery as well as assess resolution of UPJO, and the study's preliminary report suggests that HSS could turn out to be one such useful tool. In this study, those who deteriorated were the ones with HSS ≥9. One can use this as a criterion and decide on intervention before DRF deterioration. Hydronephrosis severity score could also be applied as an objective parameter for quantifying improvement/deterioration after surgery and comparing outcomes across centers. The drawbacks of the present study are its small size and the retrospective nature. Further prospective studies are required to validate the usefulness of HSS.

Complications of dysgerminoma: meeting the health needs of patients in conflict zones.

A symptom of prolonged conflict is the destruction of infrastructure and healthcare systems. While the need for acute trauma services is obvious in conflict zones, patients with chronic diseases also require care. This report describes the clinical course of a young teenage girl with a large mid pelvic tumour originating from the left ovary and reaching the umbilicus. She presented with acute abdominal pain and underwent surgery in a healthcare facility within a conflict zone. She was then transferred to a neighbouring country for continuing care. The tumour is malignant. After further surgery, she required chemotherapy and will need ongoing surveillance. She has since returned to her home country. It is doubtful that she will be able to access all the care she needs. We describe her healthcare needs and discuss the disastrous effects of conflict on meeting the health needs of civilian populations in war zones.

Diuretic 99mTc DTPA renography in assessment of renal function and drainage in infants with antenatally detected hydronephrosis.

BACKGROUND/AIM: The controversy over the postnatal management of infants with antenataly detected hydronephrosis (ANH) still exists. We presented the results of diuretic 99mTc diethylenetriamine pentaacetic acid (DTPA) renography in 30 infants with the antenatal diagnosis of unilateral renal pelvic dilatation. The aim of this study was to assess the renal function determined by the pattern of drainage and split renal function (SRF) on diuretic renography and to correlate these findings with anteroposterior pelvic diameter (APD) estimated by ultrasonography. METHODS: A total of 30 infants with 60 renal units (RU) (25 boys and 5 girls, median age 6.0 months, range 2-24) presented with unilateral hydronephrosis on ultrasound in the newborn period, underwent DTPA diuretic renal scintigraphy (F+15 protocol). The median APD evaluated on perinatal ultrasound was 15 mm (range 5-30). The postnatal associated clinical diagnosis were pelviureteric junction obstruction (PUJ), simple hydronephrosis, megaureter, vesicoureteral reflux (VUR) and posterior urethral valves in 11, 10, 6, 2 and 1 infant, respectively. Images and Tmax/2 after diuretic stimulation on the background subtracted renographic curves were used as the criteria for classifying the drainage as good, partial, and poor or no drainage. The SRF was calculated with the integral method. RESULTS: Good drainage was shown in 36/60, partial drainage in 13/60 and poor or no drainage in 11/60 RU. The SRF > 40% was observed in 55/60 RU, with no RU showing SRF lower than 23.5%. In infants with severe ANH the obstruction was not excluded in 94.1%. CONCLUSION: Diuretic renography in antenatally detected hydronephrosis should be a useful tool in postnatal follow up, especially in differentiating nonobstructive hydronephrosis from obstructive. It is also importanat to assess and monitor the SRF. Our results suggest that even in the presence of partial or no drainage, SRF may not be significantly impaired.

Hydronephrosis in patients with cervical cancer: an assessment of morbidity and survival.

PURPOSE: Hydronephrosis is a frequently observed but understudied complication in patients with cervical cancer. To better characterize hydronephrosis in cervical cancer patients, the current study sought (1) to describe hydronephrosis-associated morbidity and (2) to analyze the prognostic effect of hydronephrosis in patients with a broad range of cancer stages over time. METHODS: The Mayo Clinic Tumor Registry was interrogated for all invasive cervical cancer patients seen at the Mayo Clinic from 2008 through 2013 in Rochester, Minnesota; these patients' medical records were then reviewed in detail. RESULTS: Two hundred seventy-nine cervical cancer patients with a median age of 49 years and a range of cancer stages were included. Sixty-five patients (23 %) were diagnosed with hydronephrosis at some point during their disease course. In univariate analyses, hydronephrosis was associated with advanced cancer stage (p < 0.0001), squamous histology (p = 0.0079), and nonsurgical cancer treatment (p = 0.0039). In multivariate analyses, stage and tumor histology were associated with hydronephrosis. All but one patient underwent stent placement or urinary diversion; hydronephrosis-related morbidity included pain, urinary tract infections, nausea and vomiting, renal failure, and urinary tract bleeding. In landmark univariate survival analyses, hydronephrosis was associated with worse survival at all time points. In landmark multivariate analyses (adjusted for patient age, stage, cancer treatment, and tumor histology), hydronephrosis was associated with a trend toward worse survival over time (hazard ratios ranged from 1.47 to 4.69). CONCLUSION: Hydronephrosis in cervical cancer patients is associated with notable morbidity. It is also associated with trends toward worse survival-even if it occurs after the original cancer diagnosis.

Assessment of ureterovesical jet dynamics in obstructed ureter by urinary stone with color Doppler and duplex Doppler examinations.

This study was designed to evaluate ureterovesical jet dynamics in obstructed ureter and to compare it with those of contralateral unobstructed side. Forty-six patients with diagnosis of ureteral stone, based on imaging findings in computed tomography were enrolled in this study. The gray-scale ultrasound exam from both kidneys and urinary bladder was performed. Then, ureterovesical jet characteristics including ureteral jet frequency, duration and peak velocity were assessed by color Doppler and duplex Doppler studies in both obstructed and unobstructed ureters by a radiologist, 15-30 min after oral hydration with 750-1,000 mL of water. When compared with contralateral normal side, the ureterovesical jet in obstructed ureter showed less frequency (0.59 vs. 3.04 jets/min; P < 0.05), shorter duration (1.24 vs. 5.26 s; P < 0.05) and lower peak velocity (5.41 vs. 32.09 cm/s; P < 0.05). The cut-off points of 1.5 jets/min, 2.5 s and 19.5 cm/s for difference of ureteral jet frequency, duration and peak velocity between obstructed and contralateral normal ureters yielded sensitivities of 97.8, 95.6 and 100 % and specificities of 87, 87.9 and 97.8 %, respectively for diagnosis of ureteral obstruction. Given the safety of Doppler study and significant differences in flow dynamics of obstructed versus unobstructed ureters, our findings demonstrated the utility of Doppler ultrasound examination as a useful adjunct to gray-scale ultrasound by improving the accuracy of ultrasound exam in diagnosis of ureteral obstruction.

[(99m)Tc-MAG3 diuretic renography in assessment of obstructive uropathy. The new test F+10SP: a step ahead in the differential diagnosis]. / Scintigrafia renale sequenziale con diuretico (99m)Tc-MAG3, nella valutazione della uropatia ostruttiva. La nuova procedura F+10SP: un passo avanti nella diagnosi differenziale.

BACKGROUND: Dilation of the renal pelvis is a problem Urologists have often to deal with. One of the key aspects is to clear if the dilation is the consequence of an obstruction to the outflow or a simple anatomic variant. Aim of this study was to compare two diuretic renographic procedures, F-15 vs the new procedure F+10SP (Seated Position) in a group of hydronephrotic patients, in order to increase the accuracy in the differential diagnosis between non-obstructive and obstructive dilation. MATERIALS AND METHODS: 34 Patients (14 male, 20 female, 18-71 yrs range), 27 pts having an unilateral hydronephrosis and 7 pts a bilateral hydronephrosis diagnosed by ultrasound, were enclosed in the study. They were subjected to two 99mTc-MAG3 diuretic renography with furosemide consecutively, with different modalities: 1) 40 mg of furosemide were administered IV to patient in supine position 15 minutes before tracer injection (Test F-15, by English); 2) the new procedure: 20 mg of furosemide were administered IV to patient in Seated Position (SP), 10 minutes after tracer injection during dynamic acquisition (Test F+10 SP). The average interval between the two tests was 7 days. Two different physicians analyzed all the tests. The results were classified as: non-obstruction (only F+10SP can distinguish between normal and dilated without obstruction), obstruction, equivocal and not applicable. RESULTS: Among the 68 renal units (RU) included in the analysis, the F+10SP test showed normal findings in 21 RU (30,8%), dilation without obstruction in 21 RU (30,8%), obstruction in 25 RU (36.8%) and equivocal result in 1 RU. The F-15 renography showed non-obstructive results in 35 RU (51.5%), obstruction in 20 RU (29.4%) and equivocal findings in 11 RU (16.1%); the test was not applicable in 2 RU (2.9%) due to insufficient renal function. Side effects reported for the F-15 renogram were hypotension in 1 patient, renal colic in 3 patients, bladder filling in 13 patients, disruption because of voiding in 4 patients. No complications were observed during or after the F+10SP renography. The 20 RU diagnosed with obstruction at the F-15 test were considered obstructed also at the F+10SP test. CONCLUSIONS: The "equivocal" test rate lowered from 16% for the F-15 test to less than 1.5% for the new F+10 SP test. The F+10SP procedure is easy, well tolerated, time saving and seems to be a more reliable tool in assessment of obstructive uropathy in adults.

Direct primary or secondary percutaneous ureteral stenting: what is the most compliant option in patients with malignant ureteral obstructions?

The objective of this study was to analyze three ureteral stenting techniques in patients with malignant ureteral obstructions, considering the indications, techniques, procedural costs, and complications. In the period between June 2003 and June 2006, 45 patients with bilateral malignant ureteral obstructions were evaluated (24 males, 21 females; average age, 68.3; range, 42-87). All of the patients were treated with ureteral stenting: 30 (mild strictures) with direct stenting (insertion of the stent without predilation), 30 (moderate/severe strictures) with primary stenting (insertion of the stent after predilation in a one-stage procedure), and 30 (mild/moderate/severe strictures with infection) with secondary stenting (insertion of the stent after predilation and 2-3 days after nephrostomy). The incidence of complications and procedural costs were compared by a statistical analysis. The primary technical success rate was 98.89%. We did not observe any major complications. The minor complication rate was 11.1%. The incidence of complications for the various techniques was not statistically significantly. The statistical analysis of costs demonstrated that the average cost of secondary stenting (637 euros; SD, 115 euros) was significantly higher than that of procedures which involved direct or primary stenting (560 euros; SD, 108 euros). We conclude that one-step stenting (direct or primary) is a valid option to secondary stenting in correctly selected patients, owing to the fact that when the procedure is performed by expert interventional radiologists there are high technical success rates, low complication rates, and a reduction in costs.

[Prenatal hydronephrosis: incidence, management and final diagnoses in 2003]. / Ectasia piélica de diagnóstico prenatal. Incidencia y protocolo de estudio durante el año 2003.

BACKGROUND: Prenatal diagnosis of renal pyelectasis usually involves postnatal studies to determine whether treatment is necessary or not. OBJECTIVES: To determine the incidence of fetal pyelectasis in our environment, to review our postnatal management protocol, and to review definitive diagnoses. PATIENTS AND METHOD: We performed a retrospective review of newborns with a prenatal diagnosis of pyelectasis. The variables recorded included prenatal ultrasound examinations, gestational age, sex, anthropometric data, postnatal study (ultrasound, cystography, isotopic renogram) and indication for antibiotic prophylaxis. RESULTS: There were 21 newborns (nine boys and 12 girls). Pyelectasia were located in the right kidney in 10 patients, on the left in seven and were bilateral in four. Antibiotic prophylaxis was administered at birth in seven neonates. Postnatal ultrasound was performed at 17.19 +/- 12.7 days of life and revealed no abnormalities in seven patients, hydronephrosis grade I-II in nine, hydronephrosis grade III in three and suspected double excretion system in two. Cystourethrography and isotopic renogram were performed in six neonates. The definitive diagnoses in the 21 patients were: no abnormalities in 10, non-complicated renal dilatation in seven, double excretion system in two, vesicoureteral reflux grade IV in one and pyeloureteral stenosis in one. None of these newborns had urinary tract infection. CONCLUSIONS: The incidence of prenatal pyelectasis in our hospital is 2 %. Most pyelectasia resolve spontaneously in the first year of life and invasive investigations are not required. Adequate monitoring of these children can avoid urinary tract infections and their sequelae.

Contrast enhanced spiral computerized tomography in patients with chronic obstructive uropathy and normal serum creatinine: a single session for anatomical and functional assessment.

PURPOSE: We evaluated contrast enhanced spiral computerized tomography (CT) as a single session for the anatomical and functional assessment of patients with chronic obstructive uropathy and normal serum creatinine. MATERIALS AND METHODS: The study included 65 patients with unilateral or bilateral chronic renal obstruction and normal serum creatinine. Five patients had bilateral obstruction and the remaining 60 had unilateral obstruction and a normal contralateral kidney. Therefore, the total number of renal units was 130, that is 70 obstructed and 60 normal. All patients underwent contrast enhanced spiral CT together with excretory urography (IVP) and Tc-mercaptoacetyltriglycine renal scan. CT was used to identify the cause of obstruction and selectively determine the glomerular filtration rate (GFR) of the 2 kidneys. The diagnostic accuracy of CT for identifying the cause of hydronephrosis was compared with that of IVP. Moreover, a correlation was made between CT GFR and isotope GFR. RESULTS: Obstruction was caused by ureteropelvic junction narrowing in 25 cases, ureteral stones in 21, ureteral stricture in 20 and extrinsic ureteral obstruction in 4. Contrast enhanced spiral CT identified the cause of hydronephrosis in all obstructed kidneys (100% sensitivity), while IVP identified the cause in 52 (74% sensitivity), which was a significant difference (p <0.05). CT and IVP excluded obstruction in all normal kidneys (100% specificity). A comparison between the isotope GFR of obstructed kidneys with the corresponding CT GFR showed a perfect correlation (r = 0.78, p <0.0001). Moreover, a similar comparison between isotope GFR and CT GFR of normal kidneys showed an excellent correlation (r = 0.73, p <0.0001). In obstructed and normal kidneys mean isotope clearance was not significantly different from that of mean CT clearance. CONCLUSIONS: Contrast enhanced spiral CT is more sensitive than IVP for identifying the cause of chronic obstructive uropathy. Moreover, it is as accurate as radioisotope renal scan for calculating the total and separate kidney function. We recommend spiral CT with contrast medium as a single radiological diagnostic modality for the assessment of patients with chronic renal obstruction and normal serum creatinine.

Primary antegrade ureteric stenting: prospective experience and cost-effectiveness analysis in 50 ureters.

AIM: To evaluate the success rate and cost efficiency of primary antegrade ureteric stenting (antegrade ureteric stent insertion as a single procedure without preliminary drainage). MATERIALS AND METHODS: A policy of primary stenting was tested in 38 patients (50 ureters) with obstructive hydronephrosis, of acute or chronic onset and of benign or malignant origin. Patients with suspected pyonephrosis were excluded. Patients successfully primarily stented (group 1) were compared to a group stented as a traditional two-stage procedure (group 2). End point assessments were screening time, equipment used, procedure-related costs, bed occupancy and technical and clinical success rate. Using these cost and outcome measures, a cost-efficiency analysis was performed comparing the two strategies. RESULTS: 40/50 (80%) ureters were considered primary stent successes. The average procedure-related bed occupancy was 2 days (range 1-2 days). Simple equipment alone was successful in 16 cases. Van ( pound46/case). The mean screening time was similar for the two groups (13.5 min vs Andel dilatation catheters and peel-away sheaths were frequently used (23 ureters). Expensive equipment was rarely necessary (four cases) and average extra equipment cost was small 15.3 min; P > or = 0.05). There was a minimum saving of pound800 per successful primary stent. The cost-effectiveness of a primary antegrade stenting strategy was pound1229 vs pound2093 for secondary stenting. CONCLUSION: In carefully selected patients, the majority of obstructed ureters can be primarily stented using simple equipment. The reduced hospital stay and overall success rate significantly improves the cost competitiveness of antegrade ureteric stenting.

Assessment of painful ureterohydronephrosis during pregnancy by MR urography.

The purpose of this study was to assess the value of the fast imaging sequence called RARE (rapid acquisition with relaxation enhancement) MR urography (or RMU) in pregnant women with painful ureterohydronephrosis. A total of 17 pregnant women with an acute flank pain were examined with RMU. Results were compared with those of US, X-rays and the evolution of symptoms. The gold standard techniques used to evaluate the results of MR urography were US when it showed the entire dilated urinary tract and the nature of the obstruction (9 cases), limited intravenous urography (IVU) when performed (3 cases) or endoscopic procedure (5 cases). The accuracy of RMU in the detection of urinary tract dilatation and the localization of the level of obstruction was excellent (sensitivity 100% in our series). The determination of the type of obstruction, intrinsic vs extrinsic, was always exact. The RMU technique alone could not specify the exact nature of the obstruction. The RMU technique is able to differentiate a physiological from a pathological ureterohydronephrosis during pregnancy. It could be considered as the procedure of choice when US failed to establish the differential diagnosis.

Fast imaging MR assessment of ureterohydronephrosis during pregnancy.

PURPOSE: to assess the value of the fast imaging sequence called RARE-MR-Urography (RMU) for the diagnosis of pathologic ureterohydronephrosis during pregnancy. MATERIALS AND METHODS: 15 pregnant women with an acute flank pain were examined with RMU. Results were compared with those of ultrasonography (US), X-rays, and the evolution of symptoms. RESULTS: the accuracy of RMU in the detection of urinary tract dilatation and the localization of the level of obstruction was excellent (100%). The determination of the type of obstruction, intrinsic vs. extrinsic, was always exact. RMU alone cannot specify the exact nature of the intrinsic obstruction. Ultrasonography gave less sensitive information in terms of level (60%) and type of obstruction (53%). CONCLUSION: RMU is able to differentiate a physiological from a pathologic ureterohydronephrosis during pregnancy. It could be considered as a procedure of choice for special cases when US failed to establish this differential diagnosis.

The assessment of obstruction in the newborn with unilateral hydronephrosis by measuring the size of the opposite kidney.

We measured the size of the normal kidney opposite a unilateral hydronephrotic kidney in infants to determine if compensatory changes occurred and could be used as a diagnostic test for defining or excluding obstruction. Comparison of subgroups of neonates with unilateral hydronephrosis or multicystic renal dysplasia to normal controls demonstrated that compensatory changes do occur in the normal kidney. Normal kidneys opposite obstructed hydronephrotic kidneys requiring surgery became larger than normal for age. Normal kidneys opposite nonobstructed poorly functioning hydronephrotic kidneys whose function rapidly improved were smaller than normal for age. These changes in renal growth by the normal newborn kidney reflect renal counterbalance, which is exaggerated in this age group and which may be used to corroborate rapid changes in renal function caused by the presence or absence of obstruction. By plotting serial measurements of normal renal length on a renal growth chart, the diagnosis of obstruction in newborn hydronephrosis can be facilitated and the clinical management of the patient improved.

Evaluation of RARE-MR urography in the assessment of ureterohydronephrosis.

OBJECTIVE: The goal of this prospective study was to evaluate the value of the fast imaging sequence called RARE-MR urography (RMU) for the diagnosis of ureterohydronephrosis. MATERIALS AND METHODS: Sixty-nine patients underwent this procedure. The results were compared with those obtained by intravenous urography (IVU) and ultrasonography (US). RESULTS: The accuracy of RMU in the detection of urinary tract dilatation and the localization of the level of obstruction was excellent (100%). The determination of the type of obstruction, intrinsic versus extrinsic, was 80% by IVU and 60% for RMU. The RMU sequence alone could not specify the nature of the obstruction. Functional information about the obstructed collecting system could not be obtained. CONCLUSION: The RMU technique may be considered in the following circumstances: contraindications to IVU (allergy to contrast medium, severe renal failure), impairment of renal excretion, and failure to locate the level of obstruction by US. The absence of ionizing radiations favors the promotion of this procedure to study ureterohydronephrosis during pregnancy.

Volume expanded diuretic renography in the postnatal assessment of suspected uretero-pelvic junction obstruction.

Controversy surrounds the role of 99mTc-diethylenetriamine pentaacetic acid renography in suspected uretero-pelvic junction obstruction in early life. Accordingly, we retrospectively reviewed 18 patients (28 hydronephrotic kidneys) with a mean age of 2 mo (range: 1 wk-6 mo) who underwent a total of 36 scans using intravenous volume expansion (10 ml/kg) and furosemide diuresis (1 mg/kg). Initial scans were classified as obstructed, not obstructed or indeterminate using differential renal function, furosemide washout T 1/2 and visual assessment of tracer clearance. Those initially classified as obstructed (n = 8) have been surgically confirmed. In the indeterminate (n = 6) and nonobstructed (n = 14) groups, three and two kidneys, respectively, developed obstruction on progress scans. Mean follow-up in the nonsurgical patients was approximately 9 mo (range: 4-17 mo). A total of 13 kidneys had developed obstruction by renographic criteria, and to date 12 have surgical confirmation. Our data indicate that: (1) scans classified as obstructed correlate well with surgery; (2) an initial classification of indeterminate or nonobstructed does not exclude later development of obstruction; and (3) serial scans correctly stratify children with possible uretero-pelvic junction obstruction.

Urethral valves--treatment, results and urodynamic assessment.

Posterior urethral valves is an uncommon condition, but it poses many diagnostic and therapeutic problems. Long term follow up of these patients revealed that the majority of these boys have long term problems. In depth assessment of 10 boys with this problem revealed that their upper urinary tracts remained stable whereas urodynamic studies showed gross micturition abnormalities. Most methods of assessing the urinary tracts in these boys are invasive (eg. Intravenous urography, micturating cystography) and may indeed show no change in upper tract radiology despite marked abnormalities of micturition detected by urodynamics and which may require further investigation and treatment. We therefore recommend regular urodynamic assessment of these boys as it is accurate and initially non-invasive. Those boys with a detectable abnormality can progress to further studies.