Pelvicaliceal System Research Articles

Percutaneous Management Of Renal Pelvic Urothelial Tumors: Long-Term Followup

We present the long-term outcome of percutaneous resection of renal urothelial tumor. A total of 24 patients underwent primary percutaneous resection of renal urothelial tumor. Patients with low stage pT0-1 disease were treated primarily with percutaneous surgery. All pelvicaliceal tumors were taken for biopsy and treated with percutaneous resection. Patients with multi-segmental pelvicaliceal system involvement, stage greater than pT1, high grade histology or additional ureteral tumors were considered for nephroureterectomy. Topical chemotherapy (mitomycin C or epirubicin) was administered via nephrostomy tube or intravesical instillation after Double-J stent (Medical Engineering Corp., New York, New York) insertion. Surveillance included upper tract cytology, nephroscopy or fiberoptic ureterorenoscopy. Long-term followup was correlated with histopathology. Of the 24 cases 2 had squamous cell carcinoma, 5 had grade III transitional cell carcinoma, 15 had grade I to II transitional cell carcinoma and 2 had no tumor. Control was established with initial percutaneous resection in 18 (75%) cases and second look nephroscopy in 4. Early recurrences were detected by excretory urography (IVP) in 3 cases, small pelvic recurrences by IVP in 2, fiberoptic ureterorenoscopy in 2 and bladder tumors by flexible cystoscopy in 3 after 1 year. A total of 10 nephroscopies were performed in 5 cases, 24 flexible uretereorenoscopies in 9 and IVP in 6. Three synchronous, grade I bladder tumors were managed conventionally. All patients with high grade disease died of malignancy except one (with no further treatment) and 6 of the 15 patients with low grade noninvasive transitional cell carcinoma underwent nephroureterectomy during followup either due to progression of disease, concomitant tumor or complications. Two patients with solitary kidneys died of renal failure unrelated to malignancy. High grade tumors or tumors greater than T1 were treated with nephroureterectomy early during management. There was no perioperative mortality and 9 (60%) of the low grade cases the kidneys were preserved at a mean followup +/- SD of 64 +/- 15 months. All excised tracks from patients who underwent nephroureterectomy and the renal fossae were free of tumor on histopathological examination. Percutaneous resection of transitional cell tumor should be considered primarily in patients with early stage disease excluding tumors crossing caliceal infundibula, ureteropelvic junction tumor, tumor extending over multiple calices and synchronous ureteral tumors. The long-term outcome of low grade tumors is good and they should be managed by either form of minimally invasive surgery. Nephron sparing is possible in a large percentage of low grade disease but high grade tumors should be treated with nephroureterectomy.

Laparoscopic partial nephrectomy with suture repair of the pelvicaliceal system

Objectives Laparoscopic partial nephrectomy is emerging as a viable minimally invasive nephron-sparing option for select patients with an exophytic renal tumor. With increasing experience, we are applying laparoscopic partial nephrectomy to tumors invading more deeply into the renal parenchyma, necessitating intentional caliceal entry to ensure an adequate margin of resection. In this prospective study, we assessed the safety and efficacy of such substantive renal parenchymal resections that incorporate laparoscopic suture repair of the collecting system. Methods Since August 1999, laparoscopic partial nephrectomy was performed in 64 patients with a renal tumor. Our technique routinely involved transient clamping of the renal artery and vein, caliceal suture repair (if necessary), and renal parenchymal suture repair. Intraoperative and postoperative data from the group requiring caliceal repair (group 1, n = 27) were compared with those not requiring caliceal repair (group 2, n = 37). The mean tumor size was 3.4 ± 1.6 cm in group 1 and 2.6 ± 0.9 cm in group 2 ( P = 0.02). The mean depth of tumor invasion into the renal parenchyma was 1.5 ± 0.8 cm in group 1 and 0.9 ± 0.3 cm in group 2 ( P = 0.15). Results Laparoscopic partial nephrectomy was technically successful in all 64 cases without any open conversions. Both groups 1 and 2 were comparable in terms of total operative time (3.2 ± 0.9 hours versus 2.7 ± 1.0 hours, P = 0.06), tumor excision time (5.9 ± 1.8 minutes versus 6.0 ± 1.9 minutes, P = 0.97), and estimated blood loss (241 ± 306 mL versus 258 ± 342 mL, P = 0.27). Pelvicaliceal suture repair was associated with a longer warm ischemia time (30.2 ± 5.4 minutes versus 19.4 ± 4.9 minutes, P <0.0001), and a greater hospital stay (3.0 ± 1.7 days versus 1.8 ± 1.2 days, P = 0.003). No patients in group 1, and 1 patient in group 2, developed an asymptomatic perinephric urinoma that was drained percutaneously. On pathologic examination, inked surgical margins were negative for cancer in all but 1 case; the width of the parenchymal margin on histologic examination was 0.5 ± 0.4 cm in group 1, and 0.4 ± 0.3 cm in group 2 ( P = 0.59). The mean preoperative and postoperative serum creatinine was 1.1 and 1.2 mg/dL in group 1 and 1.0 and 1.1 mg/dL in group 2, respectively ( P = 0.4). During a mean follow-up of 9.5 ± 3.5 months in group 1 and 15.7 ± 4 months in group 2, no renal unit developed irreversible ischemic damage or local cancer recurrence. Conclusions Laparoscopic partial nephrectomy can be performed safely and efficaciously for select invasive renal tumors with intrarenal extension, even up to the collecting system. Intentional caliceal entry in such cases can be effectively repaired in a watertight manner by laparoscopic freehand suturing, albeit with longer mean operative and warm ischemia times, without adverse renal functional sequelae.

Percutaneous nephrolithotomy in the supine position: technical aspects and functional outcome compared with the prone technique

Objectives. To compare the results of percutaneous nephrolithotomy in the supine and prone positions. Methods. A total of 130 patients who underwent percutaneous nephrolithotomy for renal or upper ureteral stones were evaluated in a prospective and nonrandomized manner. The procedure was carried out in the supine or prone position in 53 and 77 patients, respectively. The results in both positions were compared regarding the technical aspects, success rate, and morbidity. Results. Regardless of the position, the pelvicaliceal system could be successfully approached in all patients, and the posterior calices were the most common site of entry. Punctures through the anterior calices were more frequently reported with the supine position. A higher incidence of anteromedial displacement of the kidney during tract dilation was reported with the supine approach. The overall success rate was 89% and 84% in the supine and prone positions, respectively. The complication rates were similar in both groups, and none of the patients experienced injury of adjacent organs. Conclusions. The approach to the pelvicaliceal system is feasible in the supine position. The success and complication rates are comparable to the prone approach.

Fluid absorption during percutaneous nephrolithotomy: does it matter?

Large amounts of irrigating fluid are used during percutaneous nephrolithotomy (PCNL). This use may be associated with migrating calculus debris, infection, and fluid absorption. This study evaluated the presence of fluid absorption during PCNL, its clinical and biochemical significance, and maneuvers to reduce it. Fluid absorption during PCNL was evaluated in 148 patients by estimating the expired breath ethanol concentration. Factors thought to affect the amount of fluid absorbed were studied, including the amount of irrigating fluid used, the number of nephrostomy tracts, the presence of a low-pressure system, the presence of existing tracts, and complications such as bleeding or perforation of the pelvicaliceal wall. Fluid absorption was evident in all patients, although no patient had any clinical or biochemical evidence of intraoperative or postoperative electrolyte imbalance. Creating a low-pressure system by using an Amplatz sheath, reducing the amount of irrigating fluid used, and staging the procedure significantly reduced the amount of fluid absorbed. Fluid absorption does take place during PCNL. This may be clinically significant in patients with compromised cardiorespiratory or renal status and in pediatric patients, leading to fluid overload. Using a low-pressure system, reducing the nephroscopy time and the amount of irrigating fluid used, and staging the procedure for large renal stone burdens, especially in the presence of complications such as perforation of the pelvicaliceal system, reduces fluid absorption and avoids volume overload. Fluid absorption may also be associated with both infective and noninfective pyrexia, necessitating adequate preoperative control of urinary infection.

LAPAROSCOPIC PARTIAL NEPHRECTOMY FOR RENAL TUMOR: DUPLICATING OPEN SURGICAL TECHNIQUES

We describe our technique of and single institutional experience with purely laparoscopic partial nephrectomy for renal tumor, wherein the focus is to duplicate established open techniques of oncologic nephron sparing surgery. Since August 1999 laparoscopic partial nephrectomy for renal tumor has been performed in 50 patients. Of the patients 24 (48%) had either a compromised contralateral kidney (20) or a solitary kidney (4). Mean tumor size was 3.0 cm. (range 1.4 to 7). In 9 patients (18%) the inner margin of the tumor was in close proximity to the pelvicaliceal system. Our current laparoscopic technique involves preoperative ureteral catheterization, laparoscopic renal ultrasonography, transient atraumatic clamping of the renal artery and vein, tumor excision with an approximate 0.5 cm. margin using cold endoshears and/or J-hook electrocautery, pelvicaliceal suture repair (if necessary) and suture repair of the renal parenchymal defect over surgicel bolsters. In 1 case renal surface hypothermia was achieved laparoscopically with ice slush. All suturing and knot tying were performed with free hand intracorporeal laparoscopic techniques exclusively. All procedures were successfully completed without open conversion. Mean surgical time was 3.0 hours (range, 0.75 to 5.8) and mean blood loss was 270.4 cc (range 40 to 1,500). Mean warm ischemia time was 23 minutes (range, 9.8 to 40). Caliceal entry in 18 cases (36%) was suture repaired in a watertight manner. Following caliceal repair, none of these 18 patients had a postoperative urine leak. Hospital stay averaged 2.2 days (range 1 to 9). Major complications occurred in 3 patients (6%) including intraoperative hemorrhage in 1, delayed hemorrhage necessitating nephrectomy in 1 and urine leak in 1. Renal cell carcinoma was confirmed on pathological examination in 34 patients (68%), and all had negative inked surgical margins for cancer. During a mean followup of 7.2 months (range 1 to 17) no patient has had local or port site recurrence or metastatic disease. Laparoscopic partial nephrectomy is a viable alternative for select patients with a renal tumor. The largest single institutional experience to date is presented wherein the open techniques of nephron sparing surgery have been duplicated laparoscopically.

US-guided Nephrostomy with the Aid of a Magnetic Field–based Navigation Device in the Porcine Pelvicaliceal System

To assess the technique and feasibility of ultrasound (US)-guided nephrostomy performed with the aid of a magnetic field-based navigation device. Twelve percutaneous nephrostomy procedures were performed in seven domestic pigs under real-time US guidance employing a navigation system. Two magnetic field sensors registered the actual position of the puncture needle and the US transducer. The actual needle position and the aimed puncture tract were graphically projected into the real-time US images, allowing exact navigation of the needle. After placement of the needle into the renal pelvis, the nephrostomy tube was inserted by means of the Seldinger technique. The puncture procedure was successfully performed in each case. The renal pelvis was punctured in a single attempt in 10 of 12 cases. In two cases, multiple attempts were necessary because bending of the puncture needle led to inaccuracies of the navigation system. With exception of two small perirenal urinomas, no complications were seen. The magnetic field-based navigation device allows easy and accurate performance of nephrostomy guided solely by US.

HYPERTENSION:: A RARE PRESENTATION OF RENAL CELL CARCINOMA

A 56-year-old man presented elsewhere with the chief complaints of headache and epistaxis 1 month in duration. Due to increased blood pressure of 215/120 and a diagnosis of essential hypertension, medical therapy with atenolol was started. After 2 months symptoms continued and the patient was referred to a cardiology clinic. Physical examination revealed a mass on the right side of the abdomen. Abdominal sonography demonstrated a right kidney mass. The patient was referred to us. He did not have a history of flank pain, discoloration of urine, dysuria, anorexia, weight loss, night sweating or cigarette smoking. There was no family history of diabetes mellitus or hypertension. Physical examination revealed high blood pressure (180/100) despite treatment with atenolol and captopril. The chest and heart were normal. During examination of the abdomen a 10 3 4 cm. firm, nontender mass was palpated in the right subcostal area, not far from the midline. Hemoglobin was 15 mg./dl. (normal 13 to 17), erythrocyte sedimentation rate 35 mm. per hour (normal less than 20), urinalysis normal, urine culture negative, blood urea nitrogen 30 mg./dl. (normal 20 to 50), creatinine 1 mg./dl. (normal 0.6 to 1.2) and alkaline phosphatase 450 units per dl. (normal 300 to 600). A 24-hour urinalysis indicated vanillylmandelic acid 3.5 mg. (normal 2 to 7). Peripheral plasma renin activity was 1 ng./ml. per hour (normal 0.2 to 2.3). Chest x-ray was normal. Excretory urography showed a mass in the right kidney with pressure effect on the right pelvicaliceal system. Computerized tomography of the abdomen confirmed a solid tumor with a hypodense area in the central portion, below the liver and right kidney, which was suggestive of renal cell carcinoma but an adrenal tumor could not be ruled out (fig. 1). The patient underwent right radical nephrectomy for right renal cell carcinoma. Convalescence was uneventful and antihypertensive drugs were discontinued. Blood pressure became stable at 140/95 on postoperative day 2, and the patient was discharged from the hospital after 5 days. Histological evaluation revealed granular type renal cell carcinoma with perinephric fat involvement but no involvement of the adrenal gland, lymph nodes or renal vein (fig. 2). Diagnosis was stage 2 renal cell carcinoma. DISCUSSION Renal cell carcinoma is a relatively prevalent cancer of the genitourinary system that can present with a wide variety of symptoms, some of which are related to the local effect of the tumor or due to secretion of hormone-like substances from tumor cells. Of these paraneoplastic symptoms hypertension, which has been reported in 14% to 35% of cases, is related to activation of the renin-angiotensin system.2 It is noteworthy that our patient presented with hypertension as a single symptom. To our knowledge this isolated occurrence is rare and a review of the literature revealed that nearly all of the patients who had hypertension due to renal cell carcinoma also had 1 or more other symptoms as well.3 Therefore, we believe that hypertension should be included in the differential diagnosis of renal cell carcinoma. With proper diagnosis and early surgical management dissemination of the tumor may be stopped and the survival of these patients improved.

Spinal dysraphism at MR urography: initial experience.

To prospectively evaluate the role of magnetic resonance (MR) urography in the radiologic assessment of patients with spinal dysraphism. Fourteen patients with spinal dysraphism were referred for MR urography with half-Fourier rapid acquisition with relaxation enhancement (RARE) (repetition time msec/echo time msec = 11.9/95) and RARE (2,800/1,100) sequences on a 1.5-T MR machine. Six patients did not tolerate MR urography owing to claustrophobia (n = 4) or flexion deformities (n = 2), giving a final success rate of 57% (eight patients). Two patients had a single kidney (one after nephrectomy, one with a crossed-fused ectopic kidney). Images were jointly assessed by two radiologists and compared with excretory urographic studies. The signal intensity ratio and contrast-to-noise ratio were also calculated. Visualization of the kidneys, pelvicaliceal system, and ureters was better with half-Fourier RARE than with RARE imaging, whereas visualization of the bladder was comparable with both sequences. The mean signal intensity ratios for half-Fourier RARE and RARE sequences, respectively, were 16.2 +/- 3.65 and 19.2 +/- 3.65 (P =. 58, factorial analysis of variance model), whereas the mean contrast-to-noise ratios were 55.4 +/- 5.16 and 47.8 +/- 5.16 (P =. 34). Cortical scarring was depicted more clearly at MR urography than at excretory urography, whereas a renal calculus seen at excretory urography was not detected at MR urography. MR urography was feasible in 57% of patients with spinal dysraphism and is a safe, accurate method of evaluating the upper urinary tract.

UPPER URINARY TRACT CHOLESTEATOMA MISDIAGNOSED AS A URETERAL TUMOR

Cholesteatoma of the upper urinary tract is a rare nonmalignant condition histologically characterized by keratinizing desquamative squamous metaplasia. Cholesteatoma has microscopic features of squamous metaplasia of the transitional epithelium and keratinization. These changes with subsequent desquamation of the superficial epithelial layers explain clinical manifestations of the disease. Flank pain, passage of cornified material in the urine and a filling defect on excretory urography (IVP) constitute the characteristic triad. Most cases are managed by extensive ablative surgery due to the potential for malignancy. A 60-year-old woman presented with a 3-year history of intermittent right flank pain in September 1999. These episodes recurred at 3 to 4-month intervals, and the pain was sometimes colicky. Medical history included hypertension and transabdominal hysterectomy for uterine myoma in 1992. Physical examination was unremarkable. Urine microscopy revealed hematuria. Urine cultures, including cultures for acid-fast bacilli, were negative. Serum blood urea nitrogen and creatinine were normal. Plain abdominal radiographs showed multiple linear calcification in the right 4th lumbar paravertebral area. IVP revealed a coarse linear filling defect in the calcified area of the proximal ureter and ureteral dilatation proximal to the involved area. A right retrograde pyelogram demonstrated a large filling defect in the proximal ureter with focal segmental narrowing and dilatation just distal to the involved area. This configuration resembled the “goblet sign” often associated with ureteral tumors (fig. 1). Computerized tomography showed right hydronephrosis with a focal filling defect in the right renal pelvic area and 1 3 1 3 5 cm. calcified mass in the right proximal ureter. Urine cytology demonstrated a moderate number of benign squamous cells and a few suspicious cells. From these findings we could not rule out a ureteral tumor. Right nephroureterectomy with bladder cuffing was done. The specimen showed a dilated pelvicaliceal system filled with whitish keratinous material extending into the proximal ureter. The mass was attatched loosely to the mucosa of the renal pelvis (fig. 2). Microscopically, there was keratinizing desquamative squamous metaplasia of the mucosa of the renal pelvis with marked keratinized debris in the renal pelvis and proximal ureter.

CYSTIC NEPHROMA: AN UNUSUAL RENAL LESION

Cystic nephroma, invariably confused with renal cell carcinoma, is rare. It has been described in the literature under various names. Recognition of this entity has a prognostic and diagnostic significance. CASE REPORT A 57-year-old man presented with a painful right renal mass and hematuria. He was mildly anemic. Kidney function tests, and films of the kidneys, ureters and bladder were normal. Excretory urography showed increased renal size, delayed excretion and splaying of pelvicaliceal system on the right side, which were confirmed on ultrasonography and computerized tomography. Urinary cytology was normal. Right nephroureterectomy was performed. The kidney was 14 3 10.5 cm. and had a 4.5 3 3.5 cm. nodule near the upper pole. On cut section this nodule was comprised of well differentiated areas of cysts filled with clear fluid, and not communicating with each other or the collecting system. There was no hemorrhage, necrosis or calcification. Microscopically, the cyst walls were comprised of cuboidal or flattened epithelium, and the supporting stroma demonstrated fibroblastic activity (see figure). DISCUSSION Multilocular cystic nephroma is rare.1 It may occur in neonates to patients 70 to 80 years old. Differential diagnoses ranging from polycystic kidney, hydronephrotic kidney, nephroblastomas and renal cell carcinoma have been made in patients with cystic nephroma. Cases with a suspicion of malignancy have been subjected to preoperative radiotherapy and chemotherapy. Multilocularity, absence of communication between the cyst and kidney tissue, presence of locules with no communication between them, locules filled with clear fluid, normal residual kidney and absence of fully developed nephrons or part of the nephron in the septa of locules, short clinical history, mass with history of pain and presence or absence of hematuria are all symptoms of multilocular cystic nephroma.2 Many consider the condition to be a developmental abnormality, that is cystic disease. Others consider it to be nephroblastoma with benign differentiation in children. 3 However, prompt diagnosis and treatment are required. Nephrectomy is the adequate treatment with no need for chemotherapy and radiotherapy. The condition should be thoroughly differentiated from nephroblastoma in children and cystic renal carcinoma in adults. There have been no reports of metastasis or recurrences in these cases.

Percutaneous nephrostomy: placement under laser guidance and real-time CT fluoroscopy.

The purpose of this paper is to present our experience with real-time computed tomography (CT) fluoroscopy guided percutaneous nephrostomy (PNT) and to describe this technique involving puncture under laser guidance. We attempted 30 placements in 25 patients: puncture was directed by laser guidance and placement of the tube was made under real time CT fluoroscopy. 25 procedures were performed in prone position and 5 procedures in the supine position. The time necessary for the procedure ranged from 10 to 45 min (mean 25 min). The average duration of CT fluoroscopy per placement was 49 seconds (range 7-110 s). The PNT placement was successful as a sole procedure including puncture and catheter placement in 24 of 30 cases; in the remainder of cases, puncture was performed under CT guidance but the catheter was definitively positioned in conventional fluoroscopy. The CT fluoroscopy technique allows routine, efficient and safe PNT placement, especially when encountering difficult access to the pelvicaliceal system.

MR Imaging-guided Percutaneous Nephrostomy and Use of MR-compatible Catheters in the Nondilated Porcine Urinary Tract

To investigate technique and practicability of MR-guided percutaneous nephrostomy (MRPCN) and to test magnetic resonance (MR)-compatible catheters inside the urinary tract. In 10 healthy pigs, a percutaneous nephrostomy tube was placed into the nonobstructed pelvicaliceal system with use of exclusive MR guidance with a standard 1.5-T magnet. The urinary tract was visualized by intravenous injection of Gd-DTPA in combination with low-dose furosemide. The procedure was controlled with use of a T1-weighted turbo gradient-echo sequence in two orthogonal planes. The equipment for MRPCN included an 18-gauge MR-compatible puncture needle, a nitinol guide wire, and different 5-F MR catheters. In all 10 animals, the puncture needle was safely directed into the nondilated target calix. Slight deviations of the needle were detected on both MR image planes, which enabled immediate correction. This technique achieved a "first attempt" puncture of the targeted calix in each animal. MR images accurately demonstrated the dysprosium labelled tip of the different inserted catheters. It proved essential to inject a gadolinium-insaline solution via these catheters to preserve the endoluminal contrast enhancement as long as necessary. Balloon catheters were directed and inflated inside the ureter under exclusive MR guidance. Complications such as perforation and leakage were visualized by MR imaging. MRPCN is a promising technique for puncturing the pelvicaliceal system. The ability to successfully enter the urinary tract, even when it is nondilated, underscores the accuracy achievable with multiplanar MR imaging.

Lower pole reflux in children: uroradiologic appearances and pitfalls.

Fig. 1-3-year 7-month-old girl with left lower pole grade 2 reflux. Voiding cystourethrogram shows renal tissue medial to uppermost calyx to be thicker than expected for single-system kidney. Uppermost infundibulum is truncated. Axis of pelvicaliceal system is oblique and points toward ipsilateral shoulder. usually the larger. Duplex kidneys are present in 12% of people and may be bilateral [I]. Most duplex kidneys are normal. Because the lower pole is the developmental analogue of a “single-system” kidney, abnormalities of the lower pole occurjust as they do in a singlesystem kidney. The most common abnormality is reflux [2, 3]; the natural history of lower pole reflux is the same as that of reflux into a single-system kidney [4].

Role of the Calices in Urine Flow with Characterization of a Caliceopelvic Sphincter and Reflex

Aim: To study the role of the caliceal system in urine flow. Methods: Eight patients (6 men, 2 women; mean age 42.6 ± 7.6 years) with an upper polar renal mass (6 renal cysts; 2 hypernephromas) which did not encroach on the pelvicaliceal system were studied. After mass removal, a manometric catheter was introduced into one of the intact calices. Another catheter was introduced through the same calix, and the calix was filled with saline in increments of 0.1 ml, and the caliceal, caliceopelvic junction (CPJ), and renal pelvis pressures were recorded. The catheter was moved to the renal pelvis, and the pressure response of the aforementioned sites to renal pelvic filling with saline in increments of 1 ml was registered. The effect of filling of the locally anesthetized calix on the pelvicaliceal pressure was also determined. Results: Caliceal filling resulted in a rise of the caliceal (p < 0.01) and a drop of the CPJ (p < 0.01) pressures with no pressure response in the renal pelvis. Renal pelvic filling produced a rise of renal pelvic (p < 0.01) and CPJ (p < 0.05) pressures; the caliceal pressure showed no change (p > 0.05). Filling of the anesthetized calix or renal pelvis produced no significant pressure changes in calix, CPJ, or renal pelvis (p > 0.05). Conclusions: The CPJ dilatation upon caliceal contraction suggests a reflex relationship which we named ‘caliceopelvic inhibitory reflex’. The reflex is suggested to effect caliceal evacuation. On the other hand, CPJ closure upon renal pelvic contraction postulates another reflex relationship which we designated ‘pelvicaliceal excitatory reflex’. This reflex seems to prevent pelvicaliceal reflux. It is suggested that a ‘functional’ sphincter exists at the CPJ.

Ultrasound-guided percutaneous nephrostomy in non-dilated pelvicaliceal system.

Percutaneous placement of nephrostomy catheters in patients with non-dilated pelvicaliceal systems remains problematic. We successfully performed ultrasound-guided percutaneous nephrostomies in 5 such patients after intravenous administration of a diuretic agent. Diuresis resulted in transient dilatation of the calyces, facilitating the procedures, which were performed under real-time sonographic guidance using the Seldinger technique. No complications were encountered.

The detection of vesicoureteral reflux in a nonfunctioning kidney on a Tc-99m DTPA renal function study.

A 7-year-old child who had previously undergone a left pyeloplasty because of vesicoureteral reflux (VUR) underwent dynamic Tc-99m-DTPA imaging for an evaluation of renal function. Dynamic images showed a nonfunctioning left kidney and a normally functioning right kidney with pelvicaliceal stasis. Following furosemide injection, the right pelvicaliceal stasis disappeared in a few minutes, while the left ureteral and subsequently left pelvicaliceal system was filling with the activity that came from the right kidney that had passed through the bladder. This drainage demonstrated a high degree VUR (Grade III) on the side of the nonfunctioning kidney. Extensive parenchymal damage was thought to be due to a high degree VUR in the left kidney. A static Tc-99m DMSA study and ultrasonography revealed the presence of left VUR nephropathy.

Water-jet dissection in renal surgery: experimental study of a new device in the pig.

The pig model was used for experiments with a new type of water-jet dissector, which produces high-pressure water by application of a gas and maintains the water fully sterile in a single-use delivery apparatus. The experiment was conducted ex vivo (14 kidneys) and in vivo to compare electric cautery section with water-jet dissection (5 vs 11 partial nephrectomies). Ex vivo study confirmed sparing of blood vessels and pelvicaliceal system. In vivo study did not show significant differences in blood loss but, the water-jet allowed precise dissection and tight closure of the excretory system. More frequent haemorrhages were noted on histological examination of the WJ group, but no coagulation necrosis. These are preliminary findings and further studies of long-term results may confirm the benefits of the absence of parenchymal necrosis and the definite advantage of precise closure of the pelvicaliceal system, as morbidity of partial nephrectomy is often related to secondary haemorrhages and urinary fistulae.

The Late Treatment of 63 Overlooked or Complicated Ureteral Missile Injuries: The Promise of Nephrostomy and Role of Autotransplantation

Purpose Nephrostomy was emphasized as an initial treatment for ureteral fistulas, internal leakage (urinoma or urinary ascites) or ureteral obstruction due to a high velocity missile injury that was overlooked during the acute phase of management or manifested after primary surgery. Autotransplantation is introduced as an option for treatment of such late sequelae. We report a large series of complicated penetrating ureteral injuries of war. Materials and Methods A series of 63 patients with war related ureteral injuries secondary to high velocity missile wounds presented with external fistulas, internal leakage or ureteral obstruction. No patient presented in the acute phase of injury, and they were referred from frontline hospitals or other departments at our hospital. The ureteral injury was missed during exploratory laparotomy in 47 patients (75 percent), while 16 (25 percent) had undergone a primary ureteral procedure elsewhere. A total of 59 patients (94 percent) had associated injuries elsewhere in the body. Nephrostomy was performed initially in 51 patients (81 percent) and various reconstructions were done in 39, including autotransplantation 2. Results Leakage, internal or external, ceased in all 46 patients who underwent nephrostomy, of whom 20 (44 percent) had a patent ureter after 3 to 8 weeks and no further reconstruction was needed. Patients were followed for 13 to 24 months (average 15), after which they had a normal excretory urogram or mild residual dilatation of the pelvicaliceal system sterile urine. Two kidneys (3.2 percent of cases) were removed due to chronic sepsis. One patient (1.6 percent) died of septicemia related to the ureteral injury and 3 (5 percent) died of associated injuries although leakage had ceased. Both autotransplanted kidneys were normal. Conclusions When treating fistulas, urinomas, urinary ascites and obstruction due to a missed ureteral injury or a complication of the primary operation, the best results are achieved with initial nephrostomy followed by reconstruction when needed. Nephrostomy was a definitive treatment in 44 percent of our cases with leakage and it protected any required reconstruction. The option of autotransplantation for an otherwise unsalvagable kidney is emphasized.

Subepithelial Hematoma of the Renal Pelvis (Antopol-Goldman Lesion)

A 26-year-old white woman was hospitalized in November 1992 with sudden onset of gross hematuria, right flank and suprapubic pain, and difficulty in urinating. Physical examination was unremarkable except for mild suprapubic tenderness and fullness. Insertion of a Foley catheter revealed gross hematuria with organized blood clots and relieved lower abdominal symptoms. Cystoscopy showed bloody efflux h m the right ureteral orifice and clots in the bladder. A right retrograde pyelogram demonstrated multiple filling defects in the right pelvicaliceal system (fig. 1). Computerized tomography of the abdomen showed no excretion of contrast material in the right renal pelvis. Right renal arteriography was nondiagnostic. Ureteros-

Effect of Internal Ureteral Stenting of Normal Ureter on the Upper Urinary Tract: An Experimental Study

The effects of internal stenting of a normal ureter on the upper urinary tract were studied in 34 male rabbits by plain films, intravenous urograms, and 99mTc-DTPA renography at weekly intervals. Moreover, pressure-flow studies of the upper urinary tract were performed, and urine specimens for culture were obtained preoperatively and at the time of sacrifice. Histopathologic examination of the kidney, ureter, and ureterovesical junction was performed after animal sacrifice. Hydroureteronephrosis and stasis with equivocal obstruction were noted after 1 week of stenting. These changes were reversible after stent removal. Prolonged stenting (> 3 weeks) produced moderate to severe hydroureteronephrosis, and renal function was lost in 2 of 18 renal units because of severe hydronephrosis or infection. Ureteral stenting did not produce obstruction at a flow rate as high as 8 ml/minute. Histopathologic examination showed dilation of the pelvicaliceal system and renal tubules, infiltration of the kidney and the ureter with inflammatory cells, mucosal ulceration, and muscular hypertrophy of the ureters. The bladder mucosa showed a severe inflammatory reaction, Brunn nests, and ulceration with occasional metaplasia. Stenting of normal ureters in rabbits produced no harmful effects on the kidney if the stents were removed within 1 week, but prolonged stenting could affect renal and ureteral integrity.