Evaluation of painful hydronephrosis in pregnancy: magnetic resonance urographic patterns in physiological dilatation versus calculous obstruction

PURPOSE: We evaluated magnetic resonance urography (MRU) appearances in symptomatic hydronephrosis in pregnancy and compared urographic patterns in physiological and calculous disease. MATERIALS AND METHODS: A total of 24 consecutive pregnant women with symptomatic hydronephrosis underwent MRU, comprising an overview fast T2-weighted examination of the abdomen and pelvis, and thick slab, heavily T2-weighted MRU images, followed by focused, high resolution T2-weighted sequences obtained in an axial and coronal oblique plane through the level of ureteral caliber change. RESULTS: Of these 24 pregnant women 15 were found to have physiological hydronephrosis, 7 had calculous disease and 2 had preexisting urinary anomalies. MRU findings in physiological hydronephrosis cases were extrinsic compression of the middle third of the ureter, no filling defect and a collapsed ureter below it. Obstruction by ureteral calculi was seen at points of ureteral narrowing in the ureter, that is at the vesicoureteral junction in 2 cases, in the compressed mid ureter in 3 and at the pelviureteral junction in 1. Nonobstructive renal calculi were seen in another patient. Calculi presented throughout pregnancy but physiological hydronephrosis presented only in the late second and third trimesters. With distal calculi the MRU appearance was the double kink sign with constriction at the pelvic brim and the vesicoureteral junction with a standing column of urine in the pelvic ureter. There was renal edema and perirenal extravasation. Small calculi were only identified using high resolution T2-weighted magnetic resonance imaging. CONCLUSIONS: MRU is a valuable and well tolerated investigation for evaluating painful hydronephrosis in pregnancy. There are characteristic and differing urographic appearances in physiological and calculous obstruction.     

磁共振水成像对上尿路梗阻的诊断价值

目的:评价磁共振水成像(MRU)对泌尿系梗阻性疾病的临床诊断价值。方法:采用快速自旋回波重T2加权序列和脂肪抑制技术,对56例经B超和IVP怀疑上尿路梗阻患者,进行泌尿系冠状位扫描,将图像按最大强度投影法重建出MRU图像。结果:其中32例MRU均能清晰显示尿路梗阻的部位和肾盂积水,解剖结构清楚,可对梗阻作出定性诊断,并经手术和病理证实为尿路梗阻者。其中尿路结石16例,尿路先天性梗阻4例,输尿管炎性狭窄2例,移植肾输尿管狭窄2例,其他8例。余26例排除上尿路梗阻。结论:MRU是无创伤的检查方法,不接触射线,不需碘对比剂,诊断尿路梗阻性疾病定位、定性准确,尤其适用于因严重梗阻IVP显影不良的病例。     

Contrast-enhanced MR urography in the evaluation of renal transplants with urological complications

AIM: The diagnostic work-up of renal transplants with impaired function due to urological problems can be difficult. This study was performed to assess sensitivity and specificity of non-invasive contrast-enhanced MR urography (MRU). METHODS AND MATERIALS: Thirty-five patients with renal transplants (25 - 71 years, mean: 53.4 years) with sonographically diagnosed hydronephrosis or perirenal fluid collections were assessed by MR urography. MR examinations were carried out at a 1.5 T clinical scanner (Vision, Siemens, Erlangen, Germany) with a 512 matrix contrast-enhanced fat-suppressed T1-weighted FLASH 3D sequence in breath-hold technique. MIP reconstructions were used to produce MR urography. MRU diagnoses were compared to operative results. RESULTS: In all patients, images with sufficient contrast in the renal collecting system were obtained. Hydronephrosis was confirmed in 20 patients, 8 patients showed a different pathology while 7 had normal findings. Compared to operative results, sensitivity of MRU was 100% with a specificity of 78%, respectively. One ureteral stone was misdiagnosed as a stricture, and 2 suspected ureteral stenoses could not be found upon operation. CONCLUSIONS: Contrast-enhanced MR urography is a highly sensitive and specific non-invasive method to evaluate patients suspected of having typical post-transplant urological complications. It may replace invasive procedures such as antegrade pyelography in the pre-operative work-up.     

Evaluation of acute renal colic: a comparison of non-contrast CT versus 3-T non-contrast HASTE MR urography

With the introduction of a 3-T scanner, magnetic resonance urography (MRU) may be an alternative imaging modality for evaluation of acute renal colic. We performed a prospective study to compare the performance of computed tomography (CT) with half-Fourier single shot turbo spin-echo (HASTE) MRU in the evaluation of patients with suspected renal colic. Patients presenting to the emergency department with acute renal colic were eligible for inclusion. Following a standard CT stone evaluation, patients underwent a non-contrast HASTE MRU study with a 3-T scanner. The presence of perinephric fluid, hydronephrosis, ureteral obstruction, and calculus was assessed. A total of 22 patients completed the study. Twenty (91 %) were diagnosed with an upper tract stone by radiographic findings. MRU detected a discrete stone in 50 % of the patients with stones detected by CT. Perinephric fluid was noted in 12 MRUs, compared to 7 CTs. Using CT as the reference standard, the combination of stone or perinephric fluid and ureteral dilation gave MRU a sensitivity of 84 %, specificity of 100 %, and accuracy of 86 % (95 % CI 0.72–1.0). HASTE MRU with a 3-T MR scanner can reliably detect the presence of upper urinary tract obstruction. Although CT imaging remains the superior modality with which to detect calculi, MRU detects a greater number of secondary signs of upper tract obstruction. For situations in which the use of ionizing radiation is undesirable, MRU is a reasonable imaging alternative.     

MRU诊断上尿路梗阻性疾病的价值

目的 探讨磁共振尿路造影（MRU）诊断上尿路梗阻性疾病的意义。方法 59例上尿路梗阻性疾病患者接受检查，MRU为冠状位快速自旋回波T2加权像。结果 所有病例MRU尿路梗阻部位及扩张状况均显示良好，其中54例经手术或病理确诊，仅2例术前MRU误诊。结论 MRU作为一种非侵袭性、无辐射损伤和不需造影剂的新技术，对上尿路梗阻性疾病的定位及定性诊断具有特殊价值，是一种可供选择的有临床实用价值的尿路成像方法。     

Evaluation of urinary cytology for upper urinary tract disease

One hundred and seventy-two patients with upper urinary tract disease were examined by cytological study of ureteral urine which was taken by ureteral catheterization. Of 139 patients with benign disease or ureteral stricture due to non-urological cancer, only one case with renal cyst revealed positive findings (false positive rate: 0.7%). Two positive cases, which were a renal hemorrhage without followup and a uterine cervical cancer with squamous cancer cells in the ureteral urine, were excluded. Although 6 of 17 (35%) uroepithelial cancers in the upper urinary tract were registered as positive, this examination was little use for detecting stage pTa, grade 1 or papillary non-invasive tumors. However, 2 out of 12 (17%) renal pelvic or ureteral cancer patients with negative results of voided urine were cytologically detected by ureteral urine. Five out of 6 cases of these cancers demonstrated malignant cells in the renal pelvic urine sampled from surgical specimen. We have recently experienced aspiration cytology for upper urinary tract disease, using the percutaneous puncture method, and five of 7 upper urinary tract patients were cytologically diagnosed. This procedure could be valuable for detecting even patients with associated bladder cancer or failure of ureteral catheterization.     

Impact of magnetic resonance urography on preoperative diagnostic workup in children affected by hydronephrosis: should IVU be replaced?

Purpose: The aim of this study was to determine the role of magnetic resonance urography (MRU) in preoperative diagnostic workup of children with hydronephrosis in a prospective clinical study with comparison of MRU, standard diagnostic investigations, and intraoperative findings. Methods: Thirty-one children with hydronephrosis secondary to different causes underwent ultrasound scan (US), intravenous urography (IVU), micturation cysto-urethrography (MCU), isotope nephrography (ING) and MRU. For MRU the authors performed sagittal and coronal halve-Fourier SSFSE scans in a 1.5 Tesla MR system. T₁- and T₂-weighted sequences were used in axial orientation to improve morphologic information. In 24 patients, preoperative data were compared with intraoperative findings. Results: Comparison of the different imaging modalities proved MRU to be able to provide more detailed information about the correct localization of stenoses along the urinary tract and the morphology of renal parenchyma. MRU showed the highest concordance of all imaging modalities with intraoperative findings. Conclusion: As a reliable investigation, MRU has the potentials to replace IVU in preoperative diagnostic workup of hydronephrosis in childhood. J Pediatr Surg 37:1441-1445.     

磁共振尿路成像在泌尿外科疾病诊断中的应用

目的：探讨磁共振尿路成像（MRU）对泌尿外科疾病的诊断价值。方法：总结58例泌尿外科患者接受MRU检查的临床资料。结果：肾结核6例,MRU有典型征象;各种先天畸形27例,MRU均清晰显示其尿路形态;肾盂癌2例,MRU不能明确诊断,确诊需结合临床资料综合判断;输尿管癌10例,9例MRU输尿管梗阻部位有截断影;输尿管息肉2例,MRU显示输尿管梗阻部位可见泡沫样充盈缺损,但其影像不如逆行造影清晰;输尿管结石8例,MRU5例可见结石影,3例结石被高信号尿液掩盖;医源性输尿管狭窄3例,MRU均可显示梗阻部位及尿路扩张的形态。MRU检查尿路梗阻部位准确率为100％。结论：MRU用于泌尿外科疾病诊断,有其优势,也有其缺点,应正确合理应用。     

Hydronephrosis in pregnancy: simultaneous depiction of fetal and maternal hydronephrosis by magnetic resonance urography

Magnetic resonance urographic (MRU) techniques possess image quality and diagnostic capability that are improving with increasingly sophisticated imaging sequences and shorter scanning times. We describe the application of a fast breath-hold MR sequence (HASTE) in the assessment of ureteric obstruction in pregnancy. In the patient presented, HASTE MRU was successful in depicting ureteral anatomy and demonstrated dilation of both ureters below the level of the pelvic brim. This observation suggested distal ureteral obstruction rather than simple hydronephrosis of pregnancy. As a result, bilateral nephrostomies were performed and neonatal prematurity was avoided. Interestingly, in this patient, HASTE MR imaging also showed evidence of concurrent fetal hydronephrosis.     

Magnetic resonance urography in pediatric urology

OBJECTIVE: To evaluate the efficiency of magnetic resonance urography (MRU) in pediatric urology. MATERIAL AND METHODS: We report retrospectively on 12 children who underwent MRU between January 1999 and November 2001. MRU was performed to accurately evaluate the entire urinary tract because of megaureter, ectopic ureter, vesicoureteral reflux, Y-inverted duplication and hydronephrosis because of pyeloureteral stenosis. T1- and T2-weighted images were obtained in the coronal, sagittal and axial planes. The mean age of the children (8 females, 4 males) investigated was 36 months (range 2-140 months). RESULTS: An accurate anatomical picture of the entire urinary tract could be obtained in all children. The obstructive nature of megaureter could be differentiated. The distal orifice of ectopic ureter could be identified in the vagina. Vesicoureteral reflux into the blind-ending ureteral bud of a duplicated system was accurately identified. Hydronephrosis was demonstrated to be the result of pyeloureteral stenosis. The location of stenoses was easily identified in the sagittal and coronal planes. CONCLUSIONS: MRU is an excellent imaging modality for accurately depicting the urinary tract. MRU is superior to conventional intravenous urography because it does not use ionizing radiation, the gadolinium contrast medium used is not nephrotoxic and the imaging quality is excellent, reproducible and not interfered with by gas superposition. Considering the high costs and diagnostic benefit of MRU compared to intravenous urography, MRU should be performed in patients with impaired renal function, in those with an allergy to contrast medium and if anatomic relationships are not clear prior to reconstructive surgery.     

磁共振尿路成像对泌尿系疾病的诊断价值

目的评价磁共振尿路成像(Magneticresonanceurography,MRU)对泌尿系疾病的诊断价值。方法对36例泌尿系疾病患者进行MRU检查,并结合临床手术、病理资料和其他影像学资料进行回顾性分析。结果36例患者中,均有MRU阳性结果,3例肾盂、肾盏癌,4例前列腺癌,8例前列腺增生症,2例输尿管癌定性、定位明确;9例肾盂、输尿管移行段梗阻定位明确,定性有帮助;10例输尿管下段梗阻中6例诊断明确,4例未能确诊。结论MRU在泌尿系疾病的诊断中,对肿瘤的定位、定性参考价值较高,对尿路梗阻定位诊断有价值,对定性诊断帮助有其局限性。     

Is antibiotic prophylaxis necessary in infants with obstructive hydronephrosis?

PURPOSE: We investigated the relationship between the level of obstruction of the upper urinary tract and the risk and onset of urinary tract infection in infants with severe obstructive hydronephrosis to determine the need for antibiotic prophylaxis. MATERIALS AND METHODS: A total of 105 patients were prenatally diagnosed with severe hydronephrosis (Society for Fetal Urology grade III or IV) due to upper urinary tract obstruction between 1994 and 2004. Of these patients 75 had ureteropelvic junction obstruction and 30 had lower ureteral obstruction. We retrospectively evaluated the clinical course and incidence of urinary tract infection during the first 12 months postnatally without antibiotic prophylaxis. RESULTS: The incidence of overall urinary tract infection during followup was 36.2% (38 of 105 patients), and it demonstrated a higher trend with lower ureteral obstruction than with ureteropelvic junction obstruction (50% vs 30.7%, p=0.063). Most cases of urinary tract infection (92.8%) occurred before age 6 months, with a mean age at onset of 2.6 months. Of 105 patients 77 (73.3%) underwent corrective surgery at a mean age of 3.8 months. The incidence of urinary tract infection before surgical correction was 33.8% at a mean age of 2.1 months. The incidence of urinary tract infection in surgical cases was significantly higher with lower ureteral obstruction than with ureteropelvic junction obstruction (54.2% vs 24.5%, p=0.011). CONCLUSIONS: Urinary tract infection in infants with severe obstructive hydronephrosis has a high incidence, occurs before age 6 months and is more common with lower ureteral obstruction than with ureteropelvic junction obstruction. These findings indicate that infants with severe hydronephrosis due to obstruction of the upper urinary tract should receive antibiotic prophylaxis.     

CORRELATION OF p53 PROTEIN EXPRESSION IN HUMAN UROTHELIAL TRANSITIONAL CELL CANCERS WITH MALIGNANT POTENTIAL AND PATIENT SURVIVAL

The p53 gene product has been detected frequently in various human malignancies. We have studied the expression of p53 protein in urothelial transitional cell cancers (TCCs) and examined its correlation with pathologic grade, stage(pT) and patient survival. Specimens from 69 surgically-resected TCCs (38 cases of urinary bladder cancer, 17 cases of ureteral cancer and 14 cases of renal pelvic cancer) were examined by immunohistochemical staining, using two anti-p53 monoclonal antibodies, PAb1801 and PAb240, and a polyclonal antibody, CM-1. Twenty-six TCCs (37.6%) were positively stained by at least one of the three antibodies. Statistical analysis showed a significant correlation between p53 expression and high pathologic grade (p less than 0.05, p less than 0.001) or progressive pathologic stage (p less than 0.01). In addition, in 51 of the patients who were available for follow-up (23 cases of urinary bladder cancer, 13 cases of ureteral cancer, and 15 cases of renal pelvic cancer), the correlation between p53 protein expression and prognosis was examined. The survival of patients exhibiting positive p53 protein expression was significantly worse than those with p53-negative tumors (p less than 0.05). These results suggest that an immunohistochemical test for p53 protein may be a useful method of evaluating the malignant potential of TCCs. Additionally, expression of p53 protein in TCCs is an indicator of a poor prognosis which should be considered in drawing up treatment strategies.     

Diuretic radionuclide urography in the diagnosis of suspected ureteral obstruction following renal transplantation

The diuretic radionuclide urogram has been shown to be an effective method to discriminate obstructive from nonobstructive hydronephrosis in nontransplanted renal units. This test was evaluated in 9 renal transplant patients with suspected partial ureteral obstruction. An obstructed pattern in 2 patients was confirmed and relieved by an operation. Nonobstructed patterns in 7 patients were verified by long-term clinical followup and subsequent ancillary testing. Accurate in all 9 cases, this investigation appears to provide a safe, noninvasive method to diagnose suspected post-transplantation ureteral obstruction.     

磁共振尿路造影在上尿路梗阻诊断中的

目的 评估磁共振尿路造影技术在诊断上尿路梗阻性疾患中的价值。方法 采用磁共振尿中造影术（ＭＲＵ）诊断上尿路梗阻患者３５例。结果 所有病例均清晰显示梗阻部位及尿路积水情况。结论 ＭＲＵ是一种无创性、无需造影剂的诊断上尿路梗阻的方法。     

磁共振泌尿系造影技术在肾移植中的临床应用

目的 评价磁共振泌尿系造影技术对揭示肾移植术后尿路梗阻部位及原因的价值。方法 用重Ｔ２加权快速自旋回波（ＦＳＥ）序列和脂肪抑制技术作ＭＲ泌尿系成像２８例,原发病均为慢性肾炎尿毒症,均为首次移植。临床诊断急性排斥３例,移植肾肾功能延迟恢复１例,Ｂ超显示移植肾轻度积水２例,移植肾、输尿管中度积水３例,所有图像均作最大信号强度投影（ＭＩＰ）处理。结果 ２７例肾移植术后均清楚显示肾实质和泌尿系集合系统高质     

Tubeless cutaneous ureterostomy: the Toyoda method revisited

PURPOSE: Cutaneous ureterostomy is a less invasive method of urinary diversion and an attractive option especially in patients at high risk. We retrospectively examined the long-term outcome of the method introduced by Toyoda. MATERIALS AND METHODS: Since 1983 the Toyoda cutaneous ureterostomy has been performed in 61 patients (103 renal units) with a minimum of 3 months of followup. The ureteral patency rate was reviewed. RESULTS: Of the 92 renal units (89%) that achieved a tubeless condition 53 (51%) had no hydronephrosis, 23 (22%) had mild to moderate hydronephrosis without the need for treatment, 14 (14%) were not evaluated during followup and 2 (2%) were removed due to subsequent renal pelvic and/or ureteral carcinoma. CONCLUSIONS: A high ureteral patency rate was achieved with the Toyoda cutaneous ureterostomy. This procedure is a reasonable alternative to other forms of urinary diversion.     

Renal pelvis cuff pyeloplasty for ureteropelvic junction obstruction for the high inserting ureter: an initial experience

PURPOSE: Ureteropelvic junction (UPJ) obstruction can result from a high inserting ureter without intrinsic ureteral obstruction. We describe our initial experience using a renal pelvis cuff pyeloplasty technique to treat this cause of UPJ obstruction. MATERIALS AND METHODS: We reviewed our experience regarding all children who underwent renal pelvis cuff pyeloplasty. All patients had Society for Fetal Urology grade 3 to 4 hydronephrosis on ultrasonography and radiographic confirmation of UPJ obstruction by diuretic mercaptoacetyltriglycine renography. Pyeloplasty was performed through a flank incision. A circumferential incision was made of the renal pelvis proximal to the insertion site of the ureter into the renal pelvis. Next, a catheter was passed through the UPJ to ensure uniform patency. The cuff of pelvis with the attached ureter was then sutured to the dependent portion of the pelvis. Postoperative resolution of the obstruction was evaluated by ultrasonography and mercaptoacetyltriglycine renography. RESULTS: A total of 11 children (6 boys and 5 girls) underwent renal cuff pyeloplasty for UPJ obstruction due to a high inserting ureter. Median patient age was 6 months (range 2.5 months to 2.4 years) and median followup was 11 months (8 months to 3.4 years). All patients were discharged home within 2 days postoperatively. No intraoperative or postoperative complications were noted. All patients exhibited resolution of UPJ obstruction on followup radiographs. CONCLUSIONS: Renal pelvis cuff pyeloplasty is a surgical technique for UPJ obstruction resulting from a high inserting ureter without intrinsic ureteral obstruction. The procedure was straightforward with good results and without complications in this initial experience.     

评价磁共振水成像技术对移植肾输尿管梗阻的诊断价值

目的 评价磁共振水成像（MRU）技术对移植肾输尿管梗阻的诊断价值。方法 采用MRU技术对11例B型超声波定性诊断为移植肾积水的患者进行移植肾输尿管至膀胱的磁共振扫描，按最大强度投影法重建出MRU图像。结果 11例MRU均能清晰显示移植肾输尿管梗阻的部位及积水情况，解剖结构清楚，5例显示移植肾输尿管下段-膀胱吻合口狭窄，3例为移植肾肾盂输尿管连接处狭窄，3例为移植肾肾盂、输尿管结石梗阻。结论 MRU是无创伤的检查方法，无须应用碘造影剂，对人和移植肾无损害，对梗阻性疾病定位准确，尤其适用于移植肾泌尿系统梗阻的诊断。     

Silent urothelial cancer detected by sonography after renal transplantation

OBJECTIVES: Organ transplantation increases the incidence of cancer through unclear mechanisms. In our observation, urothelial cancer happens much more frequently in Chinese people. We reviewed the detection of urothelial cancer in our series after renal transplantation. METHODS: From July 1981 to June 2005, we performed 620 renal transplantations. We do graft and native kidney sonography survey annually even if the patient is asymptomatic. During this period, 10 urothelial tumors were detected. Herein we have reviewed the findings in these cases, along with their management and outcomes. RESULTS: Moderate to severe hydronephrosis of native kidneys was observed in 14 patients, including 9 (64.3%) who had cancer including eight asymptomatic and only one with flank pain and lymph nodes metastasis succumbing in 10 months with a functioning graft. Three patients showed similar degrees of graft hydronephrosis and graft ureteral cancer was diagnosed in one. Mean time from transplantation was 5.09 years. There was a female predominance (7:3). The bladder-to-renal pelvis-to-ureter ratio was 2:5:7, which was distinct from the usual 51:3:1 distribution. In native ureter cancer, we found the left ureter more prone to develop cancer than the right (8:1). CONCLUSION: The pattern of cancer in renal transplant patients is thoroughly different from the general population, namely female predominance, with a higher incidence of ureteral and renal pelvis versus bladder cancer. In our observation, routine periodic sonography survey even in asymptomatic patients is important for urothelial tumor detection, as the incidence of cancer is surprisingly high.