Comparison of renal ablation with cryotherapy, dry radiofrequency, and saline augmented radiofrequency in a porcine model.

BACKGROUND: Needle ablative therapy has recently generated a lot of interest in the urologic community. We compare renal lesions produced in a porcine model using three forms of needle ablative energy: cryoablation (CR), dry radiofrequency (RF), and saline augmented radiofrequency (SARF). STUDY DESIGN: In 10 farm pigs, under ultrasonographic guidance, 40 laparoscopic renal lesions were produced: 825-mm CR lesions were produced with 2.4-mm cryoprobes (Endocare Inc, Irvine, CA), after 1-mL preinfusions of 14.6% saline, 12 SARF lesions were created with 22-gauge needles (2 mL/minute 14.6% saline, 50 W 510 kHz RF for 60 seconds), 12 RF lesions were created with a 2-cm array LeVeen electrode and an RF2000 generator using impedance limited 30 to 60 W double activations (Radiotherapeutics Corp, Mountain View, CA), and 8 RF lesions were produced using 22-gauge needles and double 10 W activations with the RF2000 generator. Eight animals were sacrificed after 1 week for acute pathology. An additional two animals were sacrificed at 8 weeks to provide chronic pathology results for the LeVeen dry RF and SARF modalities. RESULTS: CR produced a regular 18- to 22-mm zone of complete necrosis bordered by a 1.5- to 2.5-mm zone of partial necrosis. Acutely, LeVeen RF and single-needle RF produced lesions 25 to 45 mm and 6 to 10 mm wide, respectively. Acutely, SARF produced irregular cone-shaped lesions 15 to 31 mm wide. Only one of eight acute LeVeen RF lesions showed complete necrosis; none of the four 8-week LeVeen RF lesions displayed complete necrosis. Two of the four 8-week SARF lesions displayed complete necrosis. The remainder of the LeVeen RF, single-needle RF, and SARF lesions showed early, indeterminate tubular damage with relative glomerular sparing and bands of complete necrosis (0.5 to 1.5 mm) and inflammation (0.5 to 2 mm) at the periphery. Only CR could be consistently monitored with laparoscopic ultrasonography. CONCLUSIONS: Renal cryoablation produces well-defined, completely necrotic lesions that can be monitored reliably with ultrasonography. Longer followup may be required to characterize the full extent of renal necrosis produced by RF, but in the short run, none of the RF modalities reliably produced 100% necrosis in all cases.

Laparoscopic repair of diaphragmatic defect by total intracorporeal suturing: clinical and technical considerations.

OBJECTIVE: The use of laparoscopy in urology is increasing. Tumor of the kidney or adrenal gland and, in some cases, metastatic disease can involve the diaphragm. We describe the application of laparoscopic suturing techniques in the case of diaphragmatic involvement with a renal tumor. METHODS: After resection of the tumor and a small area of the diaphragm, a chest tube was placed under laparoscopic guidance. The tube was kept clamped until the end of the procedure. Decreasing intraabdominal pneumoperitoneum pressure made suturing easier with less tension on the edges of the diaphragmatic incision. Nonabsorbable interrupted horizontal mattress sutures were placed to close the diaphragmatic defect. RESULTS: The repair was uneventful; no intraoperative complications occurred. Extubation was done at the end of the procedure in the operating room. The chest tube was removed on postoperative day 2, and the patient was discharged on postoperative day 3. CONCLUSIONS: Laparoscopic repair of the diaphragm should be commensurate with traditional open surgical principles. In this regard, it is essential that surgeons interested in performing "advanced" laparoscopic oncologic surgery become facile in laparoscopic suturing.

Endourologic treatment of nephrocalcinosis.

Calcifications of the kidney may be located free within the collecting system, attached to a papilla, trapped beneath the urothelium, or sequestered in the renal parenchyma. Extracorporeal shock wave lithotripsy has failed to render patients who presented with nephrocalcinosis stone free because of the submucosal location of some of the calculi. We report a unique case of symptomatic nephrocalcinosis in which the patient was rendered stone free using flexible ureteroscopy and intrarenal laser and electrohydraulic lithotripsy to treat both the attached and submucosal papillary calculi.

Local transrectal enzymatic treatment for chronic nonbacterial prostatitis and prostatodynia: initial clinical experience.

We report our initial clinical experience with local transrectal application of enzymatic treatment for chronic nonbacterial prostatitis and prostatodynia in 20 patients. Using a specially designed symptom score for evaluation of subjective treatment parameters, a statistically significant improvement of symptoms was found in the areas of pain, micturition, and recreational activities. No statistically significant differences were noted in laboratory values before and after treatment. Minimal local side effects were seen in only one patient. A favorable clinical response was noted in 75% of patients, whereas the remaining 25% showed only moderate improvement of symptoms. No patient experienced complete treatment failure.

Magnetic resonance urography in the evaluation of acute flank pain.

We report our clinical experience with magnetic resonance urography in 13 patients. This noninvasive relatively new application of magnetic resonance to initial radiologic evaluation of patients with acute flank pain offers valuable diagnostic information and may provide additional support in defining the need for possible further therapeutic intervention in selected cases.

Transrectal puncture and drainage of seminal vesicle abscess.

Seminal vesical abscesses are extremely rare. We report a case in which successful treatment was achieved using a minimally invasive transrectal approach.

Laparoscopic assisted continent urinary diversion in the pig.

PURPOSE: The ideal urinary reservoir would be low pressure, nonrefluxing and simple to construct. Hohenfellner recently described creating an in situ ureterosigmoidostomy with a 5 to 6 cm. detubularized portion of sigmoid colon and rectum (sigmoid-rectum pouch). In an effort to further study the reconstructive applications of laparoscopy, we sought to laparoscopically create a sigmoid-rectum pouch in an animal model. In addition, we sought to compare a "dunked" (right ureter) with a hand-sewn end-to-side ureterocolonic anastomosis (left ureter). MATERIALS AND METHODS: Nine male domestic pigs underwent laparoscopic creation of a continent urinary diversion. Pouch creation and the ureterocolonic anastomoses were done extracorporeally; ureteral stents were not used. Average operative time was 122 minutes. Eight pigs survived the 10 to 12 week study period. RESULTS: Mean pouch capacity was 360 cc and pouch pressure remained < 20 cm.H2O. Stones were noted on the bowel staple line in 44% of the animals. Ureterocolonic obstruction occurred in 11% of the right ureters and 33% of the left ureters. CONCLUSIONS: A laparoscopically created continent sigmoid-rectum diversion appears to be feasible. A "dunked" ureterocolonic anastomosis provides equivalent or better drainage than a traditional hand-sewn ureterocolonic anastomosis. Problems with stone formation on the titanium staple line need to be resolved.

Self-expanding permanent endoluminal stents in the ureter: technical considerations.

Herein, we report our experience with the use of self-expanding permanent endoluminal stents in the ureter. To date, we have placed endoluminal stents in 55 ureteral strictures (40 patients) caused by extrinsic ureteral obstruction in advanced cancer patients over a period of 4 years at Wels Medical Center in Austria. In an additional five patients, an endoluminal stent was utilized to treat benign ureteral strictures. In the group with malignant ureteral obstruction, extended follow-up data (range 1-44 months) are available. Median primary patency, which is patency maintained without any subsequent interventions, in all patients still alive is 23.2 months (range 6-44 months). Median overall assisted patency in all patients who required further interventions is 12.7 months (range 1-37 months). Twenty-seven patients (49%) needed additional procedures (i.e., placement of an additional overlapping wallstent or internal ureteral stent, endoscopic removal of tumor ingrowth, and removal of incrustations). While the experience with endoluminal stents in the treatment of benign ureteral strictures is still limited, they are an effective tool in the clinical management of patients with malignant obstruction. However, it must be emphasized that only strict adherence to a technically correct method of implantation will yield a successful clinical outcome.

Effect of piezoelectric energy on porcine kidneys using the EDAP LT.02.

EDAP International (Cambridge, Massachusetts) has developed a new piezoelectric lithotripter (LT.02) that differs from their earlier model (LT.01) in two important respects: method of stone visualization and available power. The LT.02 provides both in-line fluoroscopy as well as real time ultrasound. The maximum energy is 1400 Bar (compared with 1100 Bar in the LT.01). The purpose of this study was to determine whether treatment with the EDAP LT.02 piezoelectric lithotripter would cause significant renal injury in minipigs. Accordingly, 18 minipigs were divided into 3 groups of 6. Each group received a treatment of 20, 40 or 60 minutes; the power level and shock wave frequency were kept at maximal levels throughout the treatment period. Three pigs from each group were sacrificed at 72 hours (acute). The remaining 9 pigs were sacrificed 1 month following LT.02 treatment (chronic). Histopathologic analysis of the treated kidney revealed that 33% of the 9 acute pigs developed a small capsular hematoma, whereas 66% showed only a small parenchymal contusion ( < or = 1% of total renal volume). Among the chronic pigs, 66% had a small cortical scar, whereas 33% had no macroscopic pathology. Despite the differences in the number of shock waves delivered, these changes were evenly distributed among the 3 groups. Histologic acute changes included circumscribed areas of hemorrhagic infarction, vascular thrombosis with recanalization and focal tubular obstruction and damage. At 30 days, however, these acute injuries had completely resolved in 3 pigs and were only notable as minute areas of focal tubular loss in 6 pigs.

Laparoscopic repair of vesicoureteral reflux utilizing the Lich-Gregoir technique in the pig model.

To date, laparoscopic urological surgery has largely been limited to diagnostic or ablative procedures. Herein we report our experience with laparoscopic reconstructive surgery to perform an extravesical ureteral reimplantation. Seven anesthetized pigs with iatrogenic ureteral reflux underwent a laparoscopic extravesical ureteral reimplantation. The newly created ureteral tunnel varied from 2 to 4 cm. In 3 pigs, the tunnel was created with tacking staples, while in the other 4 pigs, the tunnel was created with intracorporeal suturing techniques using a 3-zero polyglyconate running suture. The procedure required an average of 132 minutes. There was one anesthetic death. There were no urinary tract infections. At 3 to 8 weeks after reimplantation, the cystograms were repeated on 5 pigs. One of 2 stapled reimplant pigs still had reflux; 1 of 3 sewn reimplant pigs had reflux. At 6 months following the reimplantation, only 1 pig had residual grade I reflux and this was a sutured reimplantation. None of the stapled reimplantations exhibited any residual reflux on the surgical side; however, in 1 animal a submucosal staple was noted at the time of harvest.

Evaluation of optimal stent size after endourologic incision of ureteral strictures.

The stent size necessary to promote optimal ureteral healing after an endoureterotomy is not known. We compared healing of an endoureterotomy over a 7F indwelling ureteral stent with healing over a 14F endopyelotomy stent. A midureteral stricture was created in each of 25 anesthetized female minipigs using an electrified stone basket passed retrograde. Six weeks later, the stricture was incised with a 24F cutting balloon device. Twenty pigs were randomized to receive a 7F or a 14F stent; four control pigs received neither incisions nor stents. At 1 week, a radiograph was performed to confirm proper stent position, and the stents were removed. At 3 months, a retrograde ureterogram was performed, and the ureters were examined grossly and harvested for histologic studies. Two of the ten pigs in each study group developed a recurrent stricture. The use of a 14F stent provided no advantage over the use of a smaller, more easily positioned 7F stent.

Adrenal involvement from renal cell carcinoma: predictive value of computerized tomography.

Although adrenal involvement from renal cell carcinoma is rare, removal of the adrenal during radical nephrectomy continues to be standard practice. To assess the actual need for adrenalectomy, we elected to evaluate whether malignant involvement of the adrenal gland could be reliably diagnosed preoperatively by a computerized tomogram (CT) of the abdomen. A blinded retrospective review of preoperative abdominal CT in 157 patients with renal cancer revealed an abnormality of the ipsilateral adrenal gland in 38. Histopathology confirmed malignant involvement of the adrenal in 10 patients. Significantly, all 119 adrenal glands judged to be normal on the preoperative CT were confirmed to be uninvolved by the renal cancer on histopathological study. We conclude that abdominal CT is reliable in the preoperative evaluation of the ipsilateral adrenal gland and assessment of its noninvolvement with renal carcinoma. In such cases adrenal sparing nephrectomy may be considered (76% of our patients). None of these 119 patients had either macroscopic or microscopic adrenal involvement. When the adrenal is not identified, displaced or enlarged on CT (24% of our patients) adrenalectomy should be routinely performed as part of radical nephrectomy. Even in this select group adrenal involvement was present in only 26% of the cases.

Endo-ureteroplasty with a free urothelial graft.

Endo-urological therapy for ureteral strictures is usually limited to lesions 1 cm. or shorter. In an attempt to develop an endo-urological approach to treat longer ureteral strictures, we studied the clinical use of a transurethrally harvested free graft of bladder urothelium placed into the incised stricture bed. A total of 6 patients with ureteral strictures 1.5 to 8 cm. long (average 2.9 cm.) underwent endo-surgical management via free urothelial graft endo-ureteroplasty. Operative time averaged 5.5 hours. Complications included urinoma in 1 patient, hyponatremia in 1 and a postoperative renal pseudoaneurysm in 1. Four patients had long-term (that is 22 months or longer) successful results. Free urothelial graft endo-ureteroplasty, while tedious, may be a useful endo-surgical technique for treatment of long ureteral strictures.

Transperitoneal nephrectomy for benign disease of the kidney: a comparison of laparoscopic and open surgical techniques.

OBJECTIVE: The objective of this study was to compare the results of laparoscopic nephrectomy for benign disease to open surgical nephrectomy for benign disease. METHODS: Twenty consecutive patients undergoing laparoscopic nephrectomy for benign disease were compared with 23 patients undergoing open surgical nephrectomy for benign disease and with 29 patients undergoing a donor nephrectomy. Data were collected in the following areas: patient age, anesthetic risk, operative time, estimated blood loss, postoperative time to resume oral intake, parenteral analgesics, oral analgesics, hospital stay, complications, and convalescence. Information was obtained through chart review, telephone interviews, and mailed questionnaires. RESULTS: Compared with open surgical nephrectomy, laparoscopic nephrectomy resulted in a statistically significant longer operative time; however, it afforded a statistically significant decrease in postoperative ileus (open group), hospital stay (both groups), oral analgesics (donor group), and convalescence (both groups). The incidence of complications was 15 percent in the laparoscopic group and 0 percent in the two open surgical groups; the majority of complications occurred during the initial seven laparoscopic procedures. CONCLUSIONS: Laparoscopic nephrectomy is a more time-consuming procedure than open surgical nephrectomy. Also, early in one's experience with this technique, the complication rate is higher than with open surgery. However, despite the newness of the technique, it results in significant benefits to the patient: decreased postoperative pain, shorter hospitalization, and more rapid convalescence.

Laparoscopic nephrectomy: the Washington University experience.

OBJECTIVE: To report our experience of laparoscopic nephrectomy for benign and malignant disease of the kidney. PATIENTS AND METHODS: Since June 25, 1990, 24 patients have undergone laparoscopic removal of the kidney at the Washington University School of Medicine (Barnes Hospital): 20 patients had benign renal disease and four patients had malignant renal disease. RESULTS: Of the 24 procedures, 23 were completed successfully using laparoscopic procedures; one operation had to be converted to an open surgical nephrectomy. The mean operative time was 340 min (benign disease) and 438 min (malignant disease). Postoperatively the mean hospital stay was 4 days; return to work or usual activities occurred after 3.4 weeks, and full recovery was achieved after 6.6 weeks. CONCLUSION: Laparoscopic nephrectomy, albeit time consuming to perform, results in minimal post-operative discomfort, a brief hospital stay and a rapid convalescence.

Percutaneous stone removal with the patient in a flank position.

We report a case of percutaneous removal of a staghorn calculus that was accomplished in a morbidly obese patient while he was in a full flank position. In this position, the stone could be successfully accessed and fragmented without compromising the pulmonary status of the patient.

Laparoscopic nephroureterectomy in the child: initial case report.

Laparoscopy in the pediatric population is beginning to be used for major therapeutic procedures. We report the completion of a laparoscopic nephroureterectomy and bladder diverticulectomy in a 6-year-old child.

Clinical experience with the Kaye nephrostomy tamponade catheter.

Herein, we report our clinical experience with achieving intraoperative hemostasis with the Kaye nephrostomy tamponade catheter. Since June 1990 this device has been used 10 times in 7 patients at our institution; in each patient immediate hemostasis of the nephrostomy tract was achieved.