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Purpose: Percutaneous biopsy obtained from a single location is prone to sampling error in large heterogeneous renal masses, leading to nondiagnostic results or failure to detect poor prognostic features. We evaluated the accuracy of percutaneous biopsy for large renal masses using a modified multi-quadrant technique vs. a standard biopsy technique.Materials and Methods: Clinical and pathological data for all patients with cT2 or greater renal masses who underwent percutaneous biopsy from 2009 to 2014 were reviewed. The multi-quadrant technique was defined as multiple core biopsies from at least 4 separate solid enhancing areas in the tumor. The incidence of nondiagnostic findings, sarcomatoid features and procedural complications was recorded, and concordance between biopsy specimens and nephrectomy pathology was compared.Results: A total of 122 biopsies were performed for 117 tumors in 116 patients (46 using the standard biopsy technique and 76 using the multi-quadrant technique). Median tumor size was 10cm (IQR: 8-12). Biopsy was nondiagnostic in 5 of 46 (10.9%) standard and 0 of 76 (0%) multi-quadrant biopsies (P = 0.007). Renal cell carcinoma was identified in 96 of 115 (82.0%) tumors and nonrenal cell carcinoma tumors were identified in 21 (18.0%). One complication occurred using the standard biopsy technique and no complications were reported using the multi-quadrant technique. Sarcomatoid features were present in 23 of 96 (23.9%) large renal cell carcinomas studied. Sensitivity for identifying sarcomatoid features was higher using the multi-quadrant technique compared to the standard biopsy technique at 13 of 15 (86.7%) vs. 2 of 8 (25.0%) (P = 0.0062).Conclusions: The multi-quadrant percutaneous biopsy technique increases the ability to identify aggressive pathological features in large renal tumors and decreases nondiagnostic biopsy rates. [ABSTRACT FROM AUTHOR]

Purpose: The efficacy of shock wave lithotripsy and percutaneous stone removal for the treatment of symptomatic lower pole renal calculi was determined., Materials and Methods: A prospective randomized, multicenter clinical trial was performed comparing shock wave lithotripsy and percutaneous stone removal for symptomatic lower pole only renal calculi 30 mm. or less., Results: Of 128 patients enrolled in the study 60 with a mean stone size of 14.43 mm. were randomized to percutaneous stone removal (58 treated, 2 awaiting treatment) and 68 with a mean stone size of 14.03 mm. were randomized to shock wave lithotripsy (64 treated, 4 awaiting treatment). Followup at 3 months was available for 88% of treated patients. The 3-month postoperative stone-free rates overall were 95% for percutaneous removal versus 37% lithotripsy (p <0.001). Shock wave lithotripsy results varied inversely with stone burden while percutaneous stone-free rates were independent of stone burden. Stone clearance from the lower pole following shock wave lithotripsy was particularly problematic for calculi greater than 10 mm. in diameter with only 7 of 33 (21%) patients becoming stone-free. Re-treatment was necessary in 10 (16%) lithotripsy and 5 (9%) percutaneous cases. There were 9 treatment failures in the lithotripsy group and none in the percutaneous group. Ancillary treatment was necessary in 13% of lithotripsy and 2% percutaneous cases. Morbidity was low overall and did not differ significantly between the groups (percutaneous stone removal 22%, shock wave lithotripsy 11%, p =0.087). In the shock wave lithotripsy group there was no difference in lower pole anatomical measurements between kidneys in which complete stone clearance did or did not occur., Conclusions: Stone clearance from the lower pole following shock wave lithotripsy is poor, especially for stones greater than 10 mm. in diameter. Calculi greater than 10 mm. in diameter are better managed initially with percutaneous removal due to its high degree of efficacy and acceptably low morbidity.

Purpose: We compared the efficacy of shock wave lithotripsy and ureteroscopy for treatment of distal ureteral calculi., Materials and Methods: A total of 64 patients with solitary, radiopaque distal ureteral calculi 15 mm. or less in largest diameter were randomized to treatment with shock wave lithotripsy (32) using an HM3 lithotriptor (Dornier MedTech, Kennesaw, Georgia) or ureteroscopy (32). Patient and stone characteristics, treatment parameters, clinical outcomes, patient satisfaction and cost were assessed for each group., Results: The 2 groups were comparable in regard to patient age, sex, body mass index, stone size, degree of hydronephrosis and time to treatment. Procedural and operating room times were statistically significantly shorter for the shock wave lithotripsy compared to the ureteroscopy group (34 and 72 versus 65 and 97 minutes, respectively). In addition, 94% of patients who underwent shock wave lithotripsy versus 75% who underwent ureteroscopy were discharged home the day of procedure. At a mean followup of 21 and 24 days for shock wave lithotripsy and ureteroscopy, respectively, 91% of patients in each group had undergone imaging with a plain abdominal radiograph, and all studies showed resolution of the target stone. Minor complications occurred in 9% and 25% of the shock wave lithotripsy and ureteroscopy groups, respectively (p value was not significant). No ureteral perforation or stricture occurred in the ureteroscopy group. Postoperative flank pain and dysuria were more severe in the ureteroscopy than shock wave lithotripsy group, although the differences were not statistically significant. Patient satisfaction was high, including 94% for shock wave lithotripsy and 87% for ureteroscopy (p value not significant). Cost favored ureteroscopy by $1,255 if outpatient treatment for both modalities was assumed., Conclusions: Ureteroscopy and shock wave lithotripsy were associated with high success and low complication rates. However, shock wave lithotripsy required significantly less operating time, was more often performed on an outpatient basis, and showed a trend towards less flank pain and dysuria, fewer complications and quicker convalescence. Patient satisfaction was uniformly high in both groups. Although ureteroscopy and shock wave lithotripsy are highly effective for treatment of distal ureteral stones, we believe that HM3 shock wave lithotripsy, albeit slightly more costly, is preferable to manipulation with ureteroscopy since it is equally efficacious, more efficient and less morbid.

Purpose: We identified the predominance of neurokinin-2 receptors and evaluated the inhibition of spontaneous contraction via the blockade of neurokinin-2 receptors in human ureteral segments., Materials and Methods: Excess ureteral segments from human subjects undergoing donor nephrectomy or reconstructive procedures were suspended in tissue baths containing Krebs buffer. After spontaneous contractions were recorded, tissues were incubated with 1 microM. solutions of phosphoramidon and captopril (to inhibit peptide degradation) and either the neurokinin-1 receptor antagonist CP 99,994, the neurokinin-2 receptor antagonist SR 48,968, the neurokinin-3 receptor antagonist SR 142,801 or dimethyl sulfoxide (control) for 1 hour. Contraction magnitude and frequency were again recorded and compared with spontaneous levels. Concentration-response curves to the tachykinins substance P, and neurokinins A and B were determined in the presence and absence of antagonists., Results: Neurokinin A increased contractility at lower concentrations than substance P or neurokinin B (p <0.013). Neurokinin-2 receptor blockade produced a 100-fold rightward shift of the concentration-response curves (p <0.013), while neurokinins 1 and 3 receptor blockade had no effect. SR 48,968 significantly reduced contractility during the 1-hour incubation period, causing a 97% reduction in spontaneous rates compared with a 29% reduction in control tissues. CP 99,994 and SR 142,801 had no significant effect., Conclusions: Neurokinin-2 is the predominant receptor subtype responsible for tachykinin induced contraction of human ureteral smooth muscle. In vitro treatment with the neurokinin-2 antagonist SR 48,968 reduces the spontaneous contraction rate by 97% in vitro. Neurokinin-2 receptor antagonists may have clinical applications for ureteral disease.

Introduction: As urologists head into the new millennium, it has become clear that laparoscopy will play a significant role in successful urologic practice. Issues that are addressed in this article include: (1) What are the new limits? (2) Technological advances. (3) Adequate training. (4) How to technically simplify the laparoscopic procedures?, Materials and Methods: To answer the stated questions a review of the literature has been undertaken together with interviews of the leading experts and laparoscopic working groups in urologic laparoscopy. The gathered information has been summarized and focussed with the aim of presenting the perspectives of laparoscopy in urology., Results and Discussion: Standardized indications for laparoscopic urological surgery are benign nephrectomy, nephroureterectomy, cryptorchidism, adrenalectomy, renal cysts, lymphocele and bilateral or relapsing varicocele. Future indications might include living donor nephrectomy, partial nephrectomy and cyst decortication for adult polycystic kidney disease. Controversy exists about the laparoscopic treatment of malignancies in the urinary tract. Whereas pelvic lymph node dissection--even if performed with decreasing frequency--is accepted worldwide, retroperitoneal lymphadenectomy for low-stage testis cancer is currently performed only at few centers. The recent breakthrough in uro-oncological laparoscopic surgery has been laparoscopic radical prostatectomy changing our views on the limits of laparoscopic urology. Endoscopic suturing devices (i.e. Endostitch) are further being developed, and a prototype reapproximating micro-clips (VCS stapler) has been used to perform a uretero-ureterostomy laparoscopically in a porcine model. Nevertheless, the ability of endoscopic suturing using the standard equipment has still to be considered as a "conditio sine qua non". Improvements for tissue division and dissection include an electrosurgical snare to perform a partial nephrectomy, the development of a pneumodissector and hydrodissector. Robotics, including the AESOP 3000 and ZEUS represent a glimpse of the future. By positioning the optique in a voice-controlled full range motion mechanic arm, the image on the screen is very steady and the ergonomics of the surgeons is increased significantly. The da Vinci-System, however, is the first system that has translated all visions of telepresence surgery into clinical reality, recently also for laparoscopic radical prostatectomy., Conclusions: The future of laparoscopic urology is a two-tiered approach. On the first tier, the advancement of complex reconstructive and ablative surgery such as laparoscopic prostatectomy or, laparoscopic retroperitoneal node dissection, will be undertaken by referral centers of expertise. It is from these individuals that we will look to in order to separate what is feasible and what is reasonable. The second tier will be focusing on simplifying the procedure for the average urologist. As such, developments such as the pneumodissector, hydrodissection, and hand assistance will bring exstirpative laparoscopy into the realm of more urologists. What is critical is that the urologic community supports both groups of laparoscopists.

Laparoscopic renal cryoablation is a minimally invasive alternative for treating renal tumors utilizing narrow probes cooled with a compressed gas such as argon or carbon dioxide. At this time, cryotherapy has shown the most promise as an alternative to partial nephrectomy as a nephron-sparing treatment for renal tumors. Radiofrequency ablation employs needle electrodes placed percutaneously directly into renal lesions to deliver energy, creating high temperatures leading to cell death. High-intensity focused ultrasound is a noninvasive technique in which focused ultrasound energy is applied to cause cell death within the focal zone. Microwave thermotherapy uses small applicators to deliver microwave energy to tissues, resulting in the generation of heat. Although RF, HIFU, and microwave thermotherapy show promise as energy sources for tumor ablation, they are in the early stages of development. Little is known about their acute and chronic histologic effects and long-term efficacy as a treatment for malignant disease. Further work is needed to develop cryosurgery and needle ablation in order to delineate what role these techniques will ultimately play in the management of RCC.

Background and Purpose: The indications for partial nephrectomy are expanding as newer and more complete data come forth. A partial nephrectomy has traditionally required a generous flank incision. We report our experience using hand-assisted laparoscopy (HAL) as a less-invasive approach to partial nephrectomies., Patients and Methods: Between October 1999 and May 2000, we performed 11 HAL partial nephrectomies. The average age of the patients was 55.7 years, the average body mass index was 25.6, and the average ASA class was 2.2. The indications for partial nephrectomy were enhancing solid renal lesions (N = 9) and nonfunctioning renal moiety in a duplicated system (N = 2). In the majority of cases, access to the renal pedicle was obtained prior to the partial nephrectomy. However, in no case did the renal artery or vein require occlusion. Several excisional techniques were employed, but all relied heavily on the Harmonic Scalpel in conjunction with the argon beam coagulator. Different hemostatic agents were applied to the renal defect, including Surgicel, Avitene, and fibrin-soaked Gelfoam activated by thrombin. In several instances, pledget reinforced sutures were placed in the renal capsule to aid with hemostasis., Results: The average operative time was 273 minutes, the estimated blood loss 319 mL, and the change in hematocrit 7.3 points. No patient required a transfusion, and there was one conversion to open. Postoperatively patients, required an average of 35.6 mg of morphine sulfate equivalent and 8.2 narcotic tablets, resumed oral intake in 1.7 days, and were discharged home in 3.3 days. There were no major complications and only two minor complications. Postoperatively, five lesions were found to be benign, four lesions were confirmed to be malignant, and two lesions were consistent with a nonfunctioning duplicated renal moiety. Specimen size averaged 180 cc, and the tumor diameter averaged 1.9 cm. There were no positive surgical margins., Conclusions: Hand-assisted laparoscopic partial nephrectomy is feasible and reproducible. The surgeon's hand in the operative field facilitates dissection, vascular control, hemostasis, and suturing. Further long-term and prospective studies are underway.

The introduction of hand-assisted laparoscopic surgery (HALS) adds another dimension to standard laparoscopy, and particularly benefits the urologic laparoscopist who performs laparoscopic renal procedures. Hand assistance shortens the initial learning curve for laparoscopic nephrectomy and creates alternatives for more experienced laparoscopists. HALS can be performed on any kidney suitable for intact removal, and is well suited to laparoscopic donor nephrectomy, radical nephroureterectomy, and radical nephrectomy with intact removal. The authors' technique, early experience, and indications for hand assistance are described in detail.

The modern day treatment of UPJO with retrograde endopyelotomy continues to evolve as experience and knowledge progress. Use of the straight lateral incision and selective use of spiral CT angiogram has refined treatment decisions with retrograde endopyelotomy further. The authors' decision-oriented approach offers guidelines for the practicing urologist. Ultimately, it is up to the urologist and the patient to select the best approach for each clinical scenario.

Objectives: Laparoscopy may be complicated by neuromuscular injuries, both to the patient and to the surgeon. We used a survey to estimate the incidence of these injuries during urologic laparoscopic surgery, to assess risk factors for these injuries, and to determine preventive measures., Methods: A survey of neuromuscular injuries associated with laparoscopy submitted to 18 institutions in the United States was completed by 18 attending urologists from 15 institutions., Results: From among a total of 1651 procedures, there were 46 neuromuscular injuries in 45 patients (2.7%), including abdominal wall neuralgia (14), extremity sensory deficit (12), extremity motor deficit (8), clinical rhabdomyolysis (6), shoulder contusion (4), and back spasm (2). Neuromuscular injuries were twice as common with upper retroperitoneal as with pelvic laparoscopy (3. 1% versus 1.5%). Among patients with neuromuscular injuries, those with rhabdomyolysis were heavier (means 91 versus 80 kg) and underwent longer procedures (means 379 versus 300 minutes), and those with motor deficits were older (means 51 versus 42 years of age). Of the surgeons, 28% and 17% reported frequent neck and shoulder pain, respectively., Conclusions: Although not common, neuromuscular injuries during laparoscopy do contribute to morbidity. Abdominal wall neuralgias, injuries to peripheral nerves, and joint or back injuries likely occur no more frequently than during open surgery, but risk of rhabdomyolysis may be increased. Positioning in a partial rather than full flank position may reduce the incidence of some injuries. Measures to reduce neuromuscular strain on the surgeon during laparoscopy should be considered.

Introduction: The evolution of minimally invasive therapy for ureteropelvic junction (UPJ) obstruction has culminated with the Acucise endopyelotomy. Antegrade endopyelotomy, laparoscopic pyeloplasty, and ureteroscopic endopyelotomy all offer excellent minimally invasive alternatives to open pyeloplasty, yet still represent more invasive techniques than the Acucise endopyelotomy in treating the obstructed UPJ., Technical Considerations: The Acucise endopyelotomy is a straightforward, efficacious, and safe procedure in the appropriate patient for treating UPJ obstruction. Under fluoroscopic guidance, the latest version of the Acucise allows the urologist to perform a retrograde pyelogram, position the Acucise catheter, make the incision, and place a ureteral stent, all over a single guide wire. In my experience, this latest technical modification has further simplified the procedure for the practicing urologist., Conclusions: In 2000, the Acucise endopyelotomy continues to represent an excellent minimally invasive option for all urologists who choose to perform endopyelotomies.

Purpose: To quantitate the effects of a selective cyclooxygenase (COX)-2 inhibitor, NS-398, on porcine and human ureteral contractility in vitro., Materials and Methods: This study was performed in 3 distinct groups. In group 1, segments of ureter were obtained from freshly sacrificed domestic swine. Sections were isolated and suspended longitudinally. Twenty-four ureteral segments were treated with either indomethacin (a nonselective COX inhibitor), NS-398 (selective COX-2 inhibitor), or DMSO (control). Spontaneous contractions were then recorded in each group. In group 2, fifteen segments of human ureter were obtained from patients undergoing donor nephrectomy or ureteral reimplantation. Segments were isolated and suspended as above, and treated with either indomethacin, NS-398, or DMSO. In group 3, eighteen sections of human ureter obtained from donor nephrectomy patients were passively sensitized for 20 hours in ragweed allergic donor serum. Ureteral segments were then treated with either indomethacin, NS-398 or DMSO, and then the segments were subsequently exposed to ragweed antigen and contractions were subsequently recorded., Results: In group 1, the average time to 100% inhibition of spontaneous contraction was 48.8 minutes (S.E.M. = 7.9) for indomethacin, 65.7 minutes (S.E.M. 6.7) for NS-398, and beyond 150 minutes for DMSO. The percent reduction was 100% for indomethacin (S.E.M. = 0), 92.5% for NS-398 (S.E.M. 4.9%), and 52.9% for DMSO (s.e.m. = 10.8%). In group 2, the average time to 100% inhibition was 29 minutes (S.E.M. = 10.4) for indomethacin, 21 minutes (S.E.M. 4.8) for NS-398, and beyond 150 minutes for DMSO. The percent reduction was 100% for indomethacin (S.E.M. = 0), 100% (S.E.M. = 0) for NS-398, and 20% (S.E.M. = 12%) for DMSO. In group 3, ragweed sensitized ureters treated with DMSO (control group) contracted an average maximum of 10 times per 5 minutes. Antigen failed to induce contractions of sensitized tissues treated with indomethacin or NS-398., Conclusion: A selective COX-2 inhibitor (NS-398) reduces ureteral contractility as effectively as indomethacin (a nonselective COX inhibitor) in both porcine and human ureteral segments in vitro (p <0.05). Selective COX-2 inhibitors may have significant clinical potential in treating renal colic as they cause less gastric ulceration.

Laparoscopic techniques are simplified and the operative time is reduced with the use of laparoscopic stapling and tacking devices. We present our experience in identifying and removing surgical tacks in 2 patients after laparoscopic pelvic surgery.

The introduction of hand-assisted laparoscopy should benefit every laparoscopic urologist. Hand assistance will shorten the learning curve for many urologists interested in performing laparoscopic renal procedures, including nephrectomy and nephroureterectomy. Advanced laparoscopists will be able to undertake more challenging procedures, including nephrectomies for inflamed, infected kidneys and live-donor nephrectomies. A step-by-step approach is presented for hand-assisted laparoscopic nephrectomy.

Variable results of open, percutaneous, and laparoscopic cryosurgery of the kidney have been reported. Minimally invasive approaches to lower-pole renal ablation were prospectively compared in swine: laparoscopic puncture cryoablation preceded by arterial embolization, laparoscopic contact cryosurgery, and arterial embolization alone. Eighteen kidneys in nine domestic pigs were randomized to one of three treatment groups of six organs each: (1) puncture cryotherapy preceded by selective lower-pole arterial embolization; (2) contact cryotherapy alone; and (3) arterial embolization alone. Under general anesthesia, appropriate animals underwent selective arterial embolization of the lower pole via femoral cutdown using Gelfoam pledgets. Animals randomized to cryotherapy underwent dissection of the lower pole of the kidney using a single 12-mm umbilical and two midclavicular-line ports in the lateral position. Under external ultrasound guidance, two 3-mm cryoprobes (Cryomedical Sciences, Rockville, MD) were positioned in the lower pole of the kidney, and double-freeze technique to -190 degrees C was performed using puncture or contact application. Ultrasonography was used to guide probe insertion during puncture cryotherapy only. Kidneys were harvested 11 to 14 days after the procedure. Both puncture and contact kidneys demonstrated cell death and subsequent necrosis by light microscopy and electron micrography. On average, puncture lesions were heavier than contact lesions, 19.3 g v 10.1 g (P = 0.02; unpaired t-test), whereas the kidneys were equivalent in weight: 74.1 g v 74.1 g. Puncture lesions represented 26.4% of total kidney weight v 13.5% in the contact group (P = 0.002; unpaired t-test). Only focal infarcts were identified in the embolization group. No evidence of adjacent visceral injury was identified in any of the groups, and no animal required conversion to open laparotomy. One kidney bled after contact cryotherapy, and hemostasis was achieved laparoscopically. Laparoscopic cryotherapy is reproducible and effective using either the puncture technique preceded by arterial embolization or the contact technique, without evidence of damage to adjacent structures. Contact lesions were less voluminous and more peripheral than puncture lesions. Embolization alone produces focal infarcts and focal zones of cell death.

Purpose: To develop an in vitro model of passive sensitization for the ureter for the study of noninfectious ureteral inflammation., Materials and Methods: Human ureteral tissues were obtained from excess segments of ureters from patients undergoing donor nephrectomy. Following excision, ureters were placed in physiologic salt solution (PSS) and passively sensitized by incubating with ragweed serum from allergic donor (1 ml. serum: 4 ml. PSS) for 20 hours at room temperature. Ureteral segments were incubated with PSS only and served as non-sensitized controls (n = 4). After sensitization, excess serum was removed by serial washing with PSS without serum. Ureteral strips were then suspended in vitro for determination of tissue contraction. Contractile responses and histamine release were measured. Tissues were then exposed to antigen. To investigate the role of inflammatory mediators in tissue contraction, 4 groups of 8 sensitized ureteral segments were incubated for 1 hour with the following substances: a H1 histamine receptor antagonist (pyrilamine), an inhibitor of prostaglandin synthesis (indomethacin), an inhibitor of leukotriene synthesis (A-64077), and a control substance (DMSO). Following incubation, the tissues were exposed to antigen, and contraction and histamine release were determined., Results: Sensitized ureteral segments (n = 8) responded to antigen with contraction (30% BaCl maximum; p <0.01) and histamine release (205/ng./gm. tissue) within the first 5 minutes of superfusion. Non-sensitized control segments (n = 4) did not respond. Both indomethacin and pyrilamine reduced (7-10% of BaCl maximum; p <0.05) the contractile response of sensitized ureter to antigen, whereas A-64077 did not. Analysis of the superfusate for histamine indicates that indomethacin reduced histamine release (150 ng./gm.) whereas A-64077 and pyrilamine did not (p <0.05)., Conclusion: We have demonstrated that ureteral segments can be passively sensitized and that subsequent antigen challenge stimulates contraction and histamine release. Our findings suggest that contraction of ureteral tissue and histamine release may be utilized as an inherent bioassay indicating the activity of inflammatory mediators. In addition, these results suggest that both prostaglandins and histamine, but apparently not leukotrienes, participate in the early inflammatory response to antigen challenge of the sensitized ureter.

Purpose: We review the morbidity and long-term outcome of percutaneous caliceal diverticulectomy and associated stone extraction., Materials and Methods: Percutaneous caliceal diverticulectomy was performed in 19 women and 11 men (age range 20 to 58 years), of whom 26 had stones (all 15 mm. or less). The diverticula were located throughout the kidney, including the upper (11 patients), middle (15) and lower (4) calices. Percutaneous caliceal diverticulectomy included 28 direct and 2 indirect accesses (1 via a previously placed nephrostomy tract and 1 due to stones in other areas of the kidney). In all cases the stone was removed and the diverticular neck was incised or dilated. Fulguration of the diverticular walls was performed in 22 cases. Transdiverticular percutaneous renal and ureteral drainage was maintained from 2 to 7 days until a nephrostogram demonstrated no extravasation., Results: The average operating room time and hospital stay were 171 minutes (range 75 to 330) and 4.1 days (range 2 to 7), respectively. Major complications occurred in 6.6% of the cases, requiring 1 blood transfusion and 1 chest tube placement, and minor complications occurred in 13.4%. There was no mortality. Followup for more than 1 year was available in 27 patients. Stone-free rate was 93% with obliteration of the diverticulum in 76% of patients. Overall, 85% of patients are asymptomatic at average followup of 3.5 years (range 1 to 7.3)., Conclusions: Direct percutaneous endosurgical management provides a safe, efficacious and durable means of treating stone bearing caliceal diverticula, regardless of stone size or location of the diverticulum.

Purpose: We compare the efficacy of percutaneous nephrostomy with retrograde ureteral catheterization for renal drainage in cases of obstruction and infection associated with ureteral calculi., Materials and Methods: We randomized 42 consecutive patients presenting with obstructing ureteral calculi and clinical signs of infection (temperature greater than 38 C and/or white blood count greater than 17,000/mm.3) to drainage with percutaneous nephrostomy or retrograde ureteral catheterization. Preoperative patient and stone characteristics, procedural parameters, clinical outcomes and costs were assessed for each group., Results: Urine cultures obtained at drainage were positive in 62.9% of percutaneous nephrostomy and 19.1% of retrograde ureteral catheterization patients. There was no significant difference in the time to treatment between the 2 groups. Procedural and fluoroscopy times were significantly shorter in the retrograde ureteral catheterization (32.7 and 5.1 minutes, respectively) compared with the percutaneous nephrostomy (49.2 and 7.7 minutes, respectively) group. One treatment failure occurred in the percutaneous nephrostomy group, which was successfully salvaged with retrograde ureteral catheterization. Time to normal temperature was 2.3 days in the percutaneous nephrostomy and 2.6 in the retrograde ureteral catheterization group, and time to normal white blood count was 2 days in the percutaneous nephrostomy and 1.7 days in the retrograde ureteral catheterization group (p not significant). Length of stay was 4.5 days in the percutaneous nephrostomy group compared with 3.2 days in the retrograde ureteral catheterization group (p not significant). Cost analysis revealed that retrograde ureteral catheterization was twice as costly as percutaneous nephrostomy., Conclusions: Retrograde ureteral catheterization and percutaneous nephrostomy effectively relieve obstruction and infection due to ureteral calculi. Neither modality demonstrated superiority in promoting a more rapid recovery after drainage. Percutaneous nephrostomy is less costly than retrograde ureteral catheterization. The decision of which mode of drainage to use may be based on logistical factors, surgeon preference and stone characteristics.

Objectives: To assess technical preferences and current practice trends of retroperitoneal and pelvic extraperitoneal laparoscopy., Methods: A questionnaire survey of 36 selected urologic laparoscopic centers worldwide was performed., Results: Twenty-four centers (67%) responded. Overall, 3988 laparoscopic procedures were reported: transperitoneal approach (n = 2945) and retroperitoneal/extraperitoneal approach (n = 1043). Retroperitoneoscopic/extraperitoneoscopic procedures included adrenalectomy (n = 74), nephrectomy (n = 299), ureteral procedures (n = 166), pelvic lymph node dissection (n = 197), bladder neck suspension (n = 210), varix ligation (n = 91), and lumbar sympathectomy (n = 6). Mean number of total laparoscopic procedures performed in 1995 per center was 41 (range 5 to 86). Major complications occurred in 49 (4.7%) patients and included visceral complications in 26 (2.5%) patients and vascular complications in 23 (2.2%). Open conversion was performed in 69 (6.6%) patients, electively in 41 and emergently in 28 (visceral injuries, n = 16; vascular injuries, n = 1 2). Retroperitoneoscopy/extraperitoneoscopy is gaining in acceptance worldwide: in 1993, the mean estimated ratio of transperitoneal laparoscopic cases versus retroperitoneoscopic/ extraperitoneoscopic cases per center was 74:26; however, in 1996 the ratio was 49:51., Conclusions: Retroperitoneoscopy and pelvic extraperitoneoscopy are important adjuncts to the laparoscopic armamentarium in urologic surgery. The overall major complication rate associated with retroperitoneoscopy/extraperitoneoscopy was 4.7%.

Purpose: The surgical management of renal and ureteral calculi presents unique challenges in the obese patient. We reviewed our recent experience with percutaneous nephrostolithotomy in patients with a body mass index greater than 30., Materials and Methods: We reviewed the records of 236 patients undergoing percutaneous nephrostolithotomy between August 1994 and March 1997 at 2 university and affiliated hospitals. Among this group 57 patients had a body mass index greater than 30 (mean plus or minus standard deviation 38.9 +/- 7.4). Renal anomalies were present in 21% of patients and more than half (56%) had co-morbidities in addition to obesity. Staghorn calculi were present in 19 patients (31.7%). In the remaining patients the mean cumulative stone size for single or multiple stones was 14.5 +/- 8.7 mm. Stone-free status after the procedure was determined by plain nephrotomograms or noncontrast computerized tomography., Results: A total of 96 procedures were performed on 60 renal units (1.6 procedures per renal unit). Average operative time for the initial procedure was 181.2 +/- 91.4 minutes. Complications occurred in 8 patients (14%) and 5 (8.8%) received a blood transfusion. Average hospital stay was 4.9 +/- 3.1 days. The overall stone-free rate was 88.3%, and stone-free rate for staghorn calculi was 84.2% compared with 90.2% for nonstaghorn calculi., Conclusions: Percutaneous nephrostolithotomy in obese patients yields a stone-free rate that is comparable to that achieved in an unselected patient population. The complication rate, transfusion rate and hospital stay are also similar. Modifications to standard technique and instrumentation are sometimes necessary to perform percutaneous nephrostolithotomy in this group of patients.

Purpose: We report our initial experience with hand assisted laparoscopic nephrectomy, and compare it to our results of standard laparoscopic nephrectomy., Materials and Methods: The results of 21 hand assisted and standard laparoscopic nephrectomies (15 simple and 4 radical nephrectomies, and 2 nephroureterectomies) were reviewed. Hand assisted laparoscopic nephrectomy was performed with a hand placed intra-abdominally using the Pneumo Sleeve,* in addition to standard laparoscopic instruments manipulated through laparoscopic ports. Standard laparoscopic nephrectomy was performed using laparoscopic instruments alone. Perioperative data were recorded and questionnaires, including visual analog pain scales, were administered prospectively to 17 of 21 cases., Results: The average operative time for 13 hand assisted laparoscopic nephrectomies was 240 minutes, which was significantly less than the 325-minute average for 8 standard laparoscopic nephrectomies (p = 0.04). Major complications tended to be more frequent in the standard group (38 versus 8%, p = 0.10). Hospital stay, return to normal activity and corrected 2-week abdominal/flank pain score in the hand assisted group (3.1 days, 14 days and 0.8, respectively) were not significantly different from the standard group (3.0 days, 10 days and 0.2, respectively)., Conclusions: Compared to standard laparoscopic techniques, hand assistance appears to facilitate the operative speed and safety of laparoscopic nephrectomy without sacrificing the benefits of minimally invasive surgery. Hand assistance may make laparoscopic nephrectomy more appealing to urologists without advanced laparoscopic experience, may facilitate the laparoscopic management of demanding pathological conditions and is particularly useful when intact specimens are required. Hand assistance, by improving manipulative ability and tactile sense, is helpful for select cases of laparoscopic nephrectomy.

Spatial anatomy of the lower renal pole, as defined by the infundibulopelvic angle (LIP angle), infundibular length (IL), and infundibular width (IW), plays a significant role in the stone-free rate after shockwave lithotripsy. A wide LIP angle, a short IL, and a broad IW, individually or in combination, favor stone clearance, whereas a LIP <70 degrees, an IL >3 cm, or an IW < or =5 mm are individually unfavorable. When all three unfavorable factors or an unfavorable LIP and IL coexist, the post-SWL stone-free rate falls to 50% or less. Using these criteria, more than one fourth of our patients with a lower-pole calculus might have been better served by an initial percutaneous or perhaps ureteroscopic procedure, neither of which is significantly affected by the lower-pole spatial anatomy.

Purpose: To examine parameters for monitoring renal cryosurgery and correlate with histopathologic necrosis in a porcine model. Parameters include: 1) tissue temperature, 2) distance of tissue from the cryosurgical probe insertion site, and 3) inclusion of tissue by the visible iceball., Materials and Methods: Following midline incision, 6 healthy kidneys from 3 domestic pigs were treated using a nitrogen-based cryosurgical system with 3.4 mm outer diameter cryoprobe. Temperatures were monitored at 6 sites in each kidney using prototype thermocouples. Gross and histologic analysis was performed on tissue harvested from each thermosensor site 24 hours postoperatively., Results: All animals survived to complete the full protocol. Post-procedure bleeding was managed surgically. Histopathology revealed that complete ablation was uniformly produced at temperatures of -19.4C or lower in 13/13 tissue samples. Within 16 mm. of the probe insertion site, cells were uniformly ablated in 17/17 samples while degree of tissue death varied widely beyond this margin. Cell death was more likely found at points encompassed by the visible iceball (16/18, 89%) than those beyond it (2/18, 11%) [p <0.0001, Chi-square] while 2/18 (11%) of samples harvested from within the iceball margin were partially viable., Conclusions: Temperature monitoring using thermocouples during porcine renal cryosurgery demonstrated complete homogeneous necrosis of tissues reaching -19.4C or lower. Distance beyond 16 mm. from the cryoprobe and direct visualization of the iceball proved to be less reliable predictors of tissue necrosis. Management of bleeding post-thaw was necessary in every case.