Antegrade Pyelography Research Articles

Percutaneous Wallstent Implantation to Rescue Failed Ureteropyelostomy for Massive Ureteral Necrosis after Renal Transplantation

A 44-year-old woman with end-stage renal disease underwent cadaver renal transplantation at another hospital. Two weeks after surgery, much clear fluid emerged from the operative wound. The patient visited our hospital and abdominal ultrasonography identified a fluid collection near the right perivesical space. A percutaneous nephrostomy was performed for urinary diversion. Antegrade pyelography showed renal pelvis distortion, an irregular surface along the entire ureter, and a severe stricture near the lower ureter, suggestive of massive ureteral necrosis of the graft. The initial treatment comprised resection of the necrotic ureter followed by an end-to-side pyeloureterostomy to join the graft renal pelvis to the middle portion of the ipsilateral native ureter. Although the postoperative period was initially unremarkable, delayed urine extravasation was noted on the fifth postoperative day. Antegrade pyelography revealed a 0.5-cm disruption gap between the graft renal pelvis and the native ureter (Fig. 1A). After discussion of the available treatment options with the patient, a metallic stent 6 mm in diameter and 30 mm in length (Wallstent; Schneider, Zurich, Switzerland) was inserted via a percutaneous antegrade approach to bridge the defect between the native ureter and graft renal pelvis. Subsequent recovery was uneventful, and antegrade pyelography showed that urine was no longer leaking from the disruption gap. The Wallstent was found to have remained in a good position (Fig. 1B) and the collecting system was patent without evidence of stone formation on three-dimensional computed tomography 10 months later. Over a 5-year follow-up period, the patient had stable renal function without sequelae.FIGURE 1.: (A) Antegrade pyelography showed a 0.5-cm ureteral disruption gap at the ureteropyelostomy anastomosis (black arrow) between the graft renal pelvis and native ureter (hollow arrow). (B) A metallic Wallstent (large arrow) was used to bridge the native ureter to the renal pelvis of the graft kidney. The small arrow indicates refluxing contrast medium in the upper portion of the right native ureter.With a reported incidence of 2.1%, ureteral necrosis is relatively uncommon after renal transplantation (1). Different techniques have been considered to repair the various types of ureteral injury. Pyeloureterostomy joining the graft pelvis to the distal portion of the native ureter is the preferred method when dealing with massive ureteral necrosis (1). Few reports have addressed further management when pyeloureterostomy fails. Antegrade or retrograde endourologic stent implantation may provide temporary relief of ureteral obstruction but can potentially lead to complications like stent encrustation or repeated urinary tract infections. Artificial ureteral replacement was successfully used in three patients with renal transplant ureteral necrosis in 1998 by Desgrandchamps et al. (2), who employed a minimally invasive technique originally described for the palliation of malignant ureteral obstructions. Based on a mean of 32-months of follow-up, the investigators concluded that the subcutaneous bypass is a simple and safe procedure, although late encrustation of the prosthesis remains a major concern. In our case, repeat operation of the disrupted pyeloureterostomy would have been difficult as a result of local inflammation. Likewise, a subcutaneous artificial ureteral replacement may not prevent persistent urine leakage from the disrupted anastomosis. Metal stents (e.g. Wallstents) are routinely used in the cardiovascular and biliary systems (3, 4) and have been deployed for malignant and benign ureteral obstruction with excellent results (5–7). The use of the technique presented in this case was able to bridge the defect caused by the disrupted pyeloureterostomy anastomosis, thereby avoiding further open surgery, with its associated morbidity. Because the presence of this new adynamic ureteral segment may cause morbidity such as stone formation in the future, regular follow-up of renal function and collecting system patency will remain crucial components in the ongoing management of this patient. Victor Chia-Hsiang Lin Division of Urology Department of Surgery E-Da HospitalI-Shou University Kaoshiung, Taiwan Alex Chien-Hwa Liao Division of Urology Department of Surgery Chi-Mei Medical Center Tainan, Taiwan Li-Ching Chang Division of Urology Department of Surgery E-Da HospitalI-Shou University Kaoshiung, Taiwan Wen-Sheng Tzeng Department of Radiology Chi-Mei Medical Center Tainan, Taiwan

Transient anuria requiring nephrostomy after intravesical bacillus Calmette‐Guérin instillations for superficial bladder cancer

A 76-year-old man received intravesical bacillus Calmette-Guérin (BCG) instillations for recurrent superficial bladder cancer. He had undergone right nephroureterectomy for right renal pelvic cancer 9 months previously. He presented with anuria and left hydronephrosis after the fourth instillation, with serum creatinine increasing up to 15.7 mg/dL. Percutaneous nephrostomy was indwelled, and antegrade pyelography showed left vesicoureteral obstruction. There was no sign of recurrent bladder cancer or ureteral cancer. He started spontaneous voiding on day 4 and the nephrostomy was removed on day 8. Most of the side-effects of intravesical BCG therapy are minor, and major adverse reactions are rare. Life-threatening ureteral obstruction would be a rare complication of BCG immunotherapy. Although BCG intravesical instillation after nephroureterectomy is a common practice, special care should be taken of renal function in patients with unilateral kidney during BCG therapy.

The Effectiveness of Non-contrast Computerized Tomography (CT) in Evaluation Ofresidual Stones after Percutaneous Nephrolithotomy

Purpose: The sensitivity of antegrade pyelogram (AGP), plain film radiography (KUB) and non-contrast, thin cut abdomen computerized tomography (CT) were prospectively compared for the detection of residual stones following a percutaneous nephrolithotomy. Materials and Methods: Fifty patients (53 renal units), who had undergone a percutaneous nephrolithotomy for radiopaque renal pelvis stone, as well as a non-contrast abdomen CT 1 month postoperatively, were prospectively evaluated. The number and size of residual fragments, as determined by immediate postoperative AGP, postoperative 1 month KUB and abdomen CT, were compared. Results: The stone-free rates according to the AGP, KUB and non-contrast CT were 73.6 (39/53), 62.3 (33/53) and 20.8% (11/53), respectively. In terms of clinically insignificant residual fragments (CIRFs), the success rates were 84.9 (45/53), 83.0 (44/53) and 41.5% (22/53), respectively. With respect to the residual stones (22 cases), which were detected by CT, but not by KUB, 45.5% (10 cases) were more than 4mm in size on CT, with a mean size of 7.4mm. The sensitivity for the detection of residual fragments was 47.6% for KUB compared to 100% for non-contrast CT. Seven patients received additional extracorporeal shock wave lithotripsy (ESWL) for residual stones following CT. Conclusions: Non-contrast, thin cut abdomen CT is the most accurate imaging modality for determination of the stone-free rate following a PCNL. Non-contrast abdomen CT gives accurate information for the selection of patients who may benefit from additional ESWL treatment and for follow-up planning. (Korean J Urol 2006;47:1315-1319) ꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏ

"VIDAUS" Videourodinamia del aparato superior: Indicaciones actuales

Upper urinary tract videourodynamic studies were first described in the second half of the 20th century (years 60-70). The antegrade pyelogram with constant pressure and controlled flow received the name of its author, "Vela Navarrete test" (1982), who currently refers to it as video-urodynamic study of the upper urinary tract. It is the simultaneous study of pressure, flow, and dynamic x-ray of the upper urinary tract and it keeps same indications than the original design, in spite of the appearance of new dynamic and static imaging techniques (ultrasound, CT scan, MRI, radioisotope studies). The continued practice of video urodynamic study of the upper urinary tract in the FJD prompted an update of the procedure reviewing its current indications. Patient is positioned in the prone decubitus on an x-ray table with video. After punctioning renal cavities with fine needle, video urodynamic tests are performed: pyelomanometry, basal pyelic pressure (basic urodynamics study), pressure changes after induced diuresis, and pressure-flow studies. 10-20 ml of urine are obtained for biochemical tests (creatinine, electrolytes, osmolarity,...), which give information about the functional viability of the renal unit, cytology or microbiological tests. Finally, the study concludes with an antegrade pyelogram, a fluoroscopic study of the radiological anatomy which provides morphologic and dynamic data of the upper urinary tract. In the Urodynamics Unit of the FJD, urologists perform 30-40 studies per year. We analyzed retrospectively all studies performed over the last five years (1999-2005) for various pathological entities of kidney dilation. (Table I). Structural and dynamic data obtained by the studies offered conclusive information in most of them facilitating the decision for surgery or observation (Table II). The interpretation of the upper urinary tract video-urodynamic study is based on radiological and dynamic findings. Flow-controlled pyelogram enables determining the existence of obstruction, dilation volume, and ureteral peristaltic behaviour. Constant pressure enables quantification of obstruction. The video urodynamic study of the upper urinary tract is easy to perform, well tolerated and may be repeated as many times as required, mainly if nephrostomy tube is placed for more prolonged evaluations. It offers excellent anatomical, dynamic, and etiological information about the upper urinary tract, and furthermore conclusive, with minimal risk.

Endourological Management is Better in Early-Onset Ureteral Stenosis in Kidney Transplantation

Introduction The incidence of ureteral stenosis in kidney transplant recipients is 3%–8%. The treatment of ureteral stenosis has been traditionally operative reconstruction, although such intervention is associated with high rates of serious complications, including graft loss and even perioperative mortality. More recently, endourological treatment has been proposed due to its low morbidity. Objective The objective of this study was to assess the usefulness of balloon percutaneous dilatation as a treatment technique for ureteral stenosis in kidney transplant recipients. Patients and Methods Among 1000 kidney transplantations performed between 1980 and 2004, the coexistence of high creatinine values and urinary tract dilatation in the postoperative period, after discarding concomitant causes, was managed with a percutaneous nephrostomy. Once renal function recovered, antegrade pyelography was performed to confirm the presence and determine the location of ureteral stenosis. Ureteral dilatation was performed using a 5-French balloon-fitted angioplasty catheter. Results Fifty-six patients were diagnosed with ureteral stenosis during follow-up, an incidence of 5.6%. Transluminal balloon dilatation was the first therapeutic option in 45 cases, whereas surgery was performed directly on 11 patients. Disappearance of the stenosis as well as maintenance of an improved creatinine level was verified in 45% of cases (20 patients). Two patients experienced graft loss. Both a short time to diagnosis after transplantation ( P = .06) and the presence of a previous acute rejection episode ( P < .05) were good prognosis factors for the endourologic solution of a ureteral stricture. Conclusions Balloon dilatation may be considered the definitive procedure for treatment of ureteral stenosis in selected cases. Percutaneous nephrostomy should be used for initial diagnosis and improvement in the renal function before attempting an open procedure.

Upper urinary tract metastases from adenocarcinoma of the colon

An unusual presentation of colorectal metastasis to the upper urinary tract is reported. The metastasis manifested as a filling defect seen during antegrade pyelography. Cytologic evaluation of aspirated material demonstrated metastatic colonic adenocarcinoma. A dilated collecting system may be caused by intraluminal material including tumor and blood clots. Whenever fixed filling defects are encountered, urine cytology should be sent even in the absence of renal parenchymal involvement by tumor. The cytological evaluation may allow for prompt diagnosis and treatment.

Actinomicosis ureteral: A propósito de un caso

To report one case of pseudotumoral lesion of the iliac ureter with obstructive uropathy leading to loss of function of the renal unit. 66-year-old male being studied for BPH who presents with a self-limited monosymptomatic hematuria. Renal ultrasound detected grade II pyelocaliectasis of the right kidney. IVU showed absence of function of the right kidney. Urine cytology was consistent with low-grade transitional cell carcinoma. Percutaneous nephrostomy was performed confirming irreversible function loss. Antegrade pyelography showed a filling defect in the right iliac ureter. Radical nephroureterectomy with bladder cuff was carried out with good results. Pathology reported chronic pyelonephritis and parietal inflammatory lesion of the ureter obliterating the lumen with inflammatory infiltrates, urothelial erosion and presence of actinomyces. Actinomycosis is a chronic bacterial infection, with A. israeli being the most common pathogen. It is part of the normal flora of the oral cavity and GI tract, and cervical-facial region is the most frequent clinical involvement (60% of the cases). Urinary tract infection is exceptional. No other focus was found in the long-term follow-up.

Memokath Metallic Stent in the Treatment of Transplant Kidney Ureter Stenosis or Occlusion

To determine the efficacy of the Memokath 051 stent (Engineers and Doctors, Hornbaek, Denmark) in the treatment of recurrent ureteral stenosis or occlusion in transplant kidneys. From October 1985 through January 2004, 1,131 renal transplantations were performed at our center. Four patients who developed recurrent renal transplant ureter obstruction had nephrostomy catheters placed. Antegrade pyelography showed ureteral stenosis in three cases and complete occlusion in one patient. In each case, a Memokath 051 stent was inserted via an antegrade approach. Mean follow-up was 20 months (range 18-21 months). Creatinine levels were measured and ultrasonography was performed during follow-up. All stent procedures were technically successful. During follow-up, one stent migrated within 10 days after stent insertion and was removed cystoscopically. Another stent had to be removed in the 14th month due to resistant infection, and was replaced with a new Memokath 051 stent which remained patent for another 8 months. The other two stents were fully patent at the 18th and 21st month of follow-up, respectively. Placement of a Memokath 051 stent appears to be a promising treatment alternative to balloon dilation, double-J stents and open surgical intervention for ureteral stenosis or occlusion in kidney transplant recipients. Further study of larger series is necessary.

THE DANGER OF INTRAOPERATIVE ANTEGRADE CANNULATION OF THE URETER IN INFANCY AND EARLY CHILDHOOD

Although the coexistence of congenital ureterovesical junction (UVJ) obstruction and ureteropelvic junction (UPJ) obstruction is rare, and should be detectable on preoperative renal/bladder ultrasonography, antegrade cannulation of the distal ureter is still a frequently used method for examination of the distal ureter to detect additional sites of ureteral narrowing or obstruction of the UVJ at the time of dismembered pyeloplasty.1– 4 We caution that this procedure is potentially dangerous, especially in infants and young children, because even gentle passage of a narrow caliber catheter may result in injury to the intramural portion of the ureter and create an obstruction of the UVJ, requiring subsequent ureteral reimplantation. We found 3 cases of secondary iatrogenic distal ureteral obstruction among 32 dismembered pyeloplasties during a 5-year period. All patients were evaluated preoperatively with sonography, voiding cystography and furosemide mercaptoacetyltriglycine renography. All patients were also evaluated with excretory urography. No case exhibited evidence of distal ureteral dilatation, although contrast visualization of the distal ureter was typically not evident due to the proximal UPJ obstruction. Retrograde pyelography was not performed, as intraoperative antegrade cannulation of the ureter at the time of dismembered pyeloplasty was routinely conducted at our surgical unit (Debrecen) to exclude distal areas of narrowing of the ureter. Postoperatively, obstruction was suspected in these 3 cases based on large residual urine volume noted at the time of intermittent clamping of the nephrostomy tube. Iatrogenic complete occlusion of the ureterovesical junction was demonstrated on postoperative antegrade pyelography, which required subsequent resection and reimplantation of the distal ureter in each case. CASE HISTORIES

Detection of Crossing Vessels as the Cause of Ureteropelvic Junction Obstruction: The Role of Antegrade Pyelography Prior To Endopyelotomy

To review the utility of antegrade pyelography in detecting crossing vessels as the cause of uretero-pelvic junction (UPJ) obstruction prior to planned endopyelotomy. A retrospective review of the medical records, surgical reports, and medical images was performed in 109 consecutive adult patients in our practice who underwent antegrade pyelography just prior to planned endopyelotomy for symptomatic UPJ obstruction between January 1996 and December 2002. Fourteen patients were identified in whom a specific antegrade pyelographic appearance was detected in the diagnosis UPJ obstruction caused by crossing vessels. Surgical plans were changed in all 14 patients from antegrade endopyelotomy to open surgical pyeloplasty, during which the anterior (ventral) crossing vessels causing obstruction were confirmed. An additional three patients in the reviewed endopyelotomy group clinically failed their initial endopyelotomy procedure and were shown at the time of subsequent open or laparoscopic reconstructive surgery to have UPJ obstruction caused by anterior crossing vessels, but that diagnosis was missed at the time of the initial antegrade pyelogram. A specific antegrade pyelographic appearance was identified to diagnose UPJ obstruction caused by anterior crossing vessels with a sensitivity of 82.4% and a specificity of 100%. The direct obstructing effect of the vessels on the ureter is defined with pyelography as an acute posteriorly angulated ureteral deformity just below a patent UPJ. Recognition of this specific antegrade pyelographic appearance permits use of an appropriate surgical technique for UPJ obstruction repair.

WILLARD E. GOODWIN: EDUCATOR, INNOVATOR AND PIONEER

No AccessJournal of UrologyHistorical Article1 Jul 2004WILLARD E. GOODWIN: EDUCATOR, INNOVATOR AND PIONEER GANESH S. PALAPATTU, DAVID A. BLOOM, ROBERT B. SMITH, and RICHARD J. BOXER GANESH S. PALAPATTUGANESH S. PALAPATTU More articles by this author , DAVID A. BLOOMDAVID A. BLOOM More articles by this author , ROBERT B. SMITHROBERT B. SMITH More articles by this author , and RICHARD J. BOXERRICHARD J. BOXER More articles by this author View All Author Informationhttps://doi.org/10.1097/01.ju.0000132123.01060.c2AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail References 1 : Studies in ketosis. J Bio Chem1937; 117: 131. Google Scholar 2 : Hematuria and sickle cell disease: unexplained, gross unilateral, renal hematuria in negroes, coincident with the blood sickling trait. J Urol1950; 63: 79. Link, Google Scholar 3 : Hemoglobinemia and lower nephron nephrosis following transurethral prostatic surgery. J Urol1951; 65: 1075. Link, Google Scholar 4 Boxer R.J. Personal interview of Peter L. Scardino, M. D. Google Scholar 5 : Percutaneous trocar (needle) nephrostomy in hydronephrosis. J Am Med Assoc1955; 157: 891. Google Scholar 6 : Human renal transplantation. I, clinical experiences with six cases of renal homotransplantation. J Urol1963; 89: 13. Link, Google Scholar 7 Boxer R.J. Personal interview of Robert S. McNamara. Google Scholar 8 Palapattu G.S. Personal interview of Joseph E. Murray, M. D. Google Scholar 9 : The ureter in renal transplantation. J Urol1969; 101: 680. Link, Google Scholar 10 : Percutaneous antegrade pyelography and hydronephrosis. Direct, intrapelvic injection of urographic contrast material to secure a pyeloureterogram after percutaneous needle puncture and aspiration of hydronephrosis. J Urol1955; 74: 164. Link, Google Scholar 11 : “Cup-patch” technique of ileocystoplasty for bladder enlargement or partial substitution. J Urol2002; 168: 667. Abstract, Google Scholar 12 : Replacement of the ureter by small intestine: clinical application and results of the “ileal ureter.”. J Urol1959; 81: 406. Link, Google Scholar 13 : Discussion on carcinoma of the prostate; diagnosis and treatment by J. C. Presti. Calif Med1953; 78: 440. Google Scholar 14 : Needle biopsy in diagnosis of prostatic cancer. Calif Med1954; 81: 308. Google Scholar 15 : The cure of hypertension by nephrectomy. Surgery1950; 28: 67. Google Scholar 16 : Three angiotensin tests in the investigation of renal hypertension; bioassay, infusion, renogram. J Urol1966; 96: 858. Abstract, Google Scholar 17 : Open, transcolonic ureterointestinal anastomosis; a new approach. Surg Gynecol Obstet1953; 97: 295. Google Scholar 18 : Experiments with intussuscepted ileal valve in ureteral substitution. J Urol1959; 81: 526. Link, Google Scholar 19 : Renal hypertension secondary to renal tuberculosis. Report of cure in four patients treated by nephrectomy. Am J Med1965; 38: 337. Google Scholar 20 : A malignant testis tumor with hepatic metastasis in a grizzly bear. J Urol1953; 69: 845. Abstract, Google Scholar From the Department of Urology, (GSP, RBS), University of California-Los Angeles School of Medicine, Los Angeles, California, Section of Urology, University of Michigan (DAB), Ann Arbor, Michigan, and Departments of Surgery/Urology, Health Policy and Community Medicine, Medical College of Wisconsin (RJB), Milwaukee, Wisconsin© 2004 by American Urological Association, Inc.FiguresReferencesRelatedDetails Volume 172Issue 1July 2004Page: 40-44 Advertisement Copyright & Permissions© 2004 by American Urological Association, Inc.MetricsAuthor Information GANESH S. PALAPATTU More articles by this author DAVID A. BLOOM More articles by this author ROBERT B. SMITH More articles by this author RICHARD J. BOXER More articles by this author Expand All Advertisement PDF DownloadLoading ...

THE VALUE OF ULTRASOUND GUIDED PERCUTANEOUS ANTEGRADE PYELOGRAPHY IN THE DIAGNOSIS OF OBSTRUCTIVE UROPATHY

Twenty-one patients with non-visualized kidney on intravenous urography (IVU), whose ultrasound (US) examinations showed moderate to severe hydronephrosis (3 of them subjected to non-conclusive retrograde uretropyelography), were included in this study. All of them underwent percutaneous antegrade pyelography (PAGP) under US guidance at Radiology Department, Saddam Teaching Hospital, Basah, form January 2000 to January 2002. Ninty-five percent of them had satisfactory and conclusive results; nine cases with radiolucent stones, 5 with congenital pelvi-ureteric junction (PUJ) obstruction, 5 with ureteric strictures and one case with severe hydrocalyces and contracted pelvis that was proved to be tuberculosis of the kidney. On the other hand, the technique failed in one case. The study included 15 males and 6 females, their ages ranged between 12-71 years and the mean age was 45 years. No complication was recorded. We conclude that this procedure is a relatively simple, safe, and useful technique to visualize the renal collecting system in certain cases allowing the surgeon to choose a more suitable operative approach for that particular condition.

Transurethral incision of ureteroneocystostomy strictures in kidney transplant recipients.

To report the treatment of patients who presented with vesico-ureteric stricture after kidney transplantation, using a minimally invasive endourological approach. Patients (10 men and four women, mean age 34 years, range 22-55) were assessed at presentation by serum creatinine level, ultrasonography and intravenous pyelography when the serum creatinine level was < 200 micromol/L. When there was hydronephrosis of the allograft a percutaneous antegrade pyelogram was taken, followed by inserting a nephrostomy. After decompression a stent nephrostomy was passed into the bladder and the strictures at the vesico-ureteric junction incised along the stent during cystoscopy. All 14 patients were treated endourologically by an endoscopic incision through the bladder; 13 fared well and one died from sepsis and transplantation problems. The mean follow-up was 8 months. Simple incision of the stricture via cystoscopy was safe and effective, and succeeded in most patients. The endourological management of ureteric lesions is feasible and is currently our first-line management of ureteric complications after kidney transplantation.

Imaging

Imaging

Antegrade pyelography for suspected ureteral obstruction in cats: 11 cases (1995-2001).

To determine sensitivity and specificity of radiography, ultrasonography, and antegrade pyelography for detection of ureteral obstructions in cats. Retrospective study. 11 cats. Medical records of cats that had radiography, ultrasonography, and antegrade pyelography performed for suspected ureteral obstructions were examined. Ultrasound-guided pyelocentesis and fluoroscopic-assisted antegrade pyelography were performed on 18 kidneys in 11 cats. Obstructive ureteral lesions were confirmed in all cats by surgical or necropsy examination. Sensitivity and specificity of survey radiography, ultrasonography, and antegrade pyelography for identification of ureteral obstructions were calculated. Surgical or necropsy findings were used as the standard for comparison. All cats were azotemic. Mean +/- SD serum creatinine and BUN concentrations were 10.2 +/- 6.1 and 149 +/- 82 mg/dL, respectively. Fifteen of 18 ureters were found to be obstructed at surgery or necropsy. Sensitivity and specificity were 60 and 100% for radiography and 100 and 33% for ultrasonography, respectively, in identification of ureteral obstructions. Leakage of contrast material developed in 8 of 18 kidneys during antegrade pyelography and prevented diagnostic interpretation in 5 of 18 studies. For the 13 diagnostic studies, specificity and sensitivity were 100% by use of the antegrade pyelography technique. Correct identification of the anatomic location of the ureteral obstruction was obtained in 100% of diagnostic antegrade pyelography studies and in 60% of radiography or ultrasonography studies. Antegrade pyelography can be a useful alternative in the diagnosis and localization of ureteral obstructions in azotemic cats, although leakage of contrast material may prevent interpretation of the study.

The Usefulness of T2-weighted MR Urography and Contrast Enhanced MR Urography in the Evaluation of Obstructive Uropathy: Comparisonal Study with Antegrade Pyelography1

Purpose: To compare the efficacy of contrast-enhanced and T2-weighted magnetic resonance urography (MRU) for the depiction of obstruction and evaluation of the causes of obstructive uropathy with that of antegrade pyelography. Materials and Methods: Twenty-five patients with obstructive uropathy who underwent percutaneous nephrostomy (PCN) and antegrade pyelography (AGP) were included in the study. We performed MR urography, comprising half-Fourier acquisition single-shot turbo spin-echo (HASTE) T2-weighted imaging and 3-D fast imaging with steady state precession (3-D FISP) T1-weighted imaging after gadolinium enhancement and compared the quality of the images of both the HASTE and 3-D FISP MRU techniques in terms of their depiction of the dilated pelvocalyceal system, and the level, type, and causes of obstruction. Results: In terms of anatomical depiction of the pelvocalyceal system (p=0.002) and the causes of obstruction (p=0.003), T1-weighted MRU using 3D-FISP was significantly better than T2-weighted MRU using the HASTE sequence. Regarding level of obstruction, T2-weighted MRU using the HASTE sequence and contrastenhanced T1-weighted MRU using 3D-FISP showed an accuracy of 76% (19/25) and 84% (21/25), respectively. In terms of type of obstruction, the accuracy of T2-weighted MRU and T1-weighted CEMRU was 72%(18/25) and 88% (22/25), respectively. Conclusion: T2-weighted MRU and T1-weighted CEMRU provided both anatomical information and that relating to impaired renal function. The two modelities played a complementary role and their use could decrease the unnecessary use of invasive diagnostic examination for the evaluation of obstructive uropathy.

LAPAROSCOPIC BLADDER FLAP URETERAL REIMPLANTATION: SURVIVAL PORCINE STUDY

The bladder or Boari flap is a useful technique for ureteroneocystostomy when the distal ureter is too short to reach the bladder without undue tension. We report our experience with laparoscopic Boari flap ureteroneocystostomy in the chronic porcine model. Six female farm pigs underwent unilateral laparoscopic Boari bladder flap ureteroneocystostomy. Refluxing direct ureteral reimplantation was performed in the initial 3 animals. In the next 3 animals a submucosal tunnel was formed to achieve nonrefluxing ureteroneocystostomy into the Boari flap. The animals were sacrificed 6 weeks after surgery. At sacrifice ascending cystography, ipsilateral antegrade pyelography and autopsy examination of the ureteroneocystostomy site was performed. No intraoperative or postoperative complications were noted. Average operative time was 140 minutes. Postoperatively serum creatinine and hemoglobin were normal in all pigs. All 3 animals with direct ureteroneocystostomy into the Boari flap had free reflux into the kidney and all 3 with a submucosal tunnel reimplant had no reflux on ascending cystography and free drainage on antegrade pyelography. Autopsy confirmed a patent anastomotic site in all 6 cases. Laparoscopic ureteroneocystostomy using the Boari bladder flap technique is feasible. Our survival porcine model confirms the successful application of the refluxing and nonrefluxing technique of ureteral reimplantation. Clinical application of the technique has the potential to decrease patient morbidity associated with traditional open surgery.

Treatment of refractory kidney transplant ureteral strictures using balloon cautery endoureterotomy

Objectives. To report our long-term clinical results with the use of endoureterotomy in patients undergoing renal transplant with a minimum follow-up of 23 months. Methods. Six renal transplant patients developed persistent ureteral obstruction demonstrated by elevated serum creatinine levels, renal ultrasound, and antegrade pyelography. Stent placement and balloon dilation were performed as the initial therapy in all patients. Persistent ureteral obstruction was managed with balloon cautery endoureterotomy. Ureteral stents were removed cystoscopically 6 weeks after the procedure. Results. Four men and 2 women, mean age 45 years (range 38 to 54), underwent eight procedures: six by way of an antegrade percutaneous approach and two in an endoscopic retrograde fashion. The sites of ureteral stricture were ureterovesical junction (n = 4), ureteropelvic junction (n = 1), and midureteroureteral (n = 1). Two patients required a second endoureterotomy 3 months after the first attempt. Patients were followed up for a mean of 27 months (range 23 to 34). The mean serum creatinine level for all patients at follow-up was 2.6 mg/dL (range 1.6 to 3.9), including a mean serum creatinine level of 1.8 mg/dL (range 1.6 to 1.9) for nonrejected kidneys and a mean of 3.4 mg/dL (range 2.5 to 3.9) in those found to have concurrent rejection. Overall, five (63%) of eight procedures were successful in 5 (83%) of 6 patients. No intraoperative complications occurred and no blood transfusions were required. Conclusions. Balloon cautery endoureterotomy was successful in this select group of renal transplant patients with persistent ureteral strictures after initial balloon dilation and stenting failed. This modality proved durable to 27 months of follow-up without significant complications.

CRITICAL ANALYSIS OF SUPRACOSTAL ACCESS FOR PERCUTANEOUS RENAL SURGERY

Percutaneous renal surgery is currently performed for complex renal calculi as well as for various other endourological indications. In many patients an upper pole nephrostomy tract allows direct access to most of the intrarenal collecting system. Upper pole percutaneous access may be obtained via the supracostal or subcostal approach. The preferred route depends on the location and size of the specific stone or lesion. Previously others have cautioned against the supracostal approach above the 12th rib and many have discouraged an approach above the 11th rib due to concern about the increased risk of intrathoracic complications. We retrospectively assessed the morbidity associated with supracostal percutaneous renal surgery and compared and analyzed the morbidity of the supracostal and subcostal approaches. The records of all patients who underwent upper pole percutaneous renal surgery between November 1993 and July 1999 were retrospectively reviewed. A total of 240 patients underwent percutaneous renal procedures, including 225 for managing symptomatic renal or ureteral stones, that is nonstaghorn calculi in 157, staghorn calculi in 41, proximal ureteral calculi in 12, calculi within a caliceal diverticulum in 6, calculi associated with primary ureteropelvic junction obstruction in 5 and calculi associated with a retained ureteral stent in 4. An additional 15 procedures were done for ureteropelvic junction obstruction (7), intrarenal collecting system tumors (5), a caliceal diverticulum without stones (1), a retained ureteral stent (1) and a ureteral stricture (1). A total of 300 nephrostomy tracts were placed to obtain access to the intrarenal collecting system via the supracostal approach in 98 (32.7%) cases and the subcostal approach in 202 (67.3%). Of the supracostal approaches 72 (73.5%) tracts were above the 12th and 26 (26.5%) were above the 11th rib. The overall complication rate irrespective of percutaneous approach was 8.3% (16.3% for supracostal and 4.5% for subcostal access). Complications included blood transfusion in 7 patients, intraoperative hemothorax/hydrothorax in 5, sepsis/bacteremia in 3, atrial fibrillation in 2, delayed nephropleural fistula in 2, renal artery pseudoaneurysm in 2, deep venous thrombosis/pulmonary embolus in 2, pneumothorax in 1 and subcapsular hematoma in 1. Seven of 8 intrathoracic complications (87.5%) developed in supracostal cases. Percutaneous renal surgery remains an important option for managing complex renal calculi and other upper urinary tract lesions. In our experience it is generally associated with low morbidity. The supracostal approach is often preferred for obtaining intrarenal access to complex renal and proximal ureteral pathology. Because supracostal access tracts are associated with significantly higher intrathoracic and overall complication rates compared to subcostal access tracts, this approach must be used with caution when no other alternatives are available.

Diagnosis of intraperitoneal urine leak in a patient with obstructive hydronephrosis using dynamic renal scintigraphy and radionuclide antegrade pyelography.

Because of the retroperitoneal location of the kidney, intraperitoneal urine leaks are uncommon. A 70-year-old woman with bilateral hydronephroses caused by invasive carcinoma of the uterine cervix had urine ascites confirmed by paracentesis. Intraperitoneal and retroperitoneal urine leaks were diagnosed by dynamic renal scintigraphy. Radionuclide antegrade pyelography revealed the location of the urine leaks. These findings show the utility of radionuclide renal imaging in the diagnosis of urine leaks.