Laparoscopic radical nephrectomy

Although open nephrectomy is the standard of care for localized renal-cell carcinoma, the significant postoperative pain and lengthy convalescence have encouraged the use of laparoscopy, which can yield similar 2- to 5-year survival rates. Either a transperitoneal or a retroperitoneal approach may be used, and sometimes, they are combined. Generally, the technique is limited to tumors <10 cm, but larger tumors can be removed. Nitrous oxide is avoided as an anesthetic agent. The dissection follows accepted oncologic principles: in situ renal dissection within Gerota's fascia, early ligation of the renal vessels, and careful removal of the specimen to prevent tumor spillage. Dissection of the hilum is facilitated by a PEER retractor and an Endoholder. On average, patients having laparoscopic radical nephrectomy return to normal activities approximately 4.5 weeks sooner than those having open surgery, a fact not taken into account in cost analyses. Laparoscopic nephrectomy may offer a special benefit in patients with known metastatic disease, as interleukin-2 administration can be started a month earlier than after open surgery. There may also be immunologic benefits of minimally invasive v open surgery. The technique and instruments continue to evolve, and cost-effectiveness should continue to improve.

Renal physiology. Laparoscopic considerations

Oliguria is a recognized component of the physiologic effect of increased intra-abdominal or retroperitoneal pressure. The cause is multifactorial, emanating from vascular and parenchymal compression, and is associated with systemic hormonal effects. Ureteral obstruction does not play a significant role. These changes are pressure-dependent and are usually not apparent until pressures reach 15 mm Hg or more. This effect is not associated with any histologic pathology or evidence of renal tubular damage. After the release of the pneumoperitoneum or pneumoretroperitoneum, the renal function and urine output return to normal with no long-term sequelae, even in patients with pre-existing renal disease. The entire operative team must understand the physiologic effects of CO2 insufflation, which allows appropriate intraoperative monitoring and management and minimizes intraoperative and postoperative complications.

Laparoscopic nephroureterectomy. A new standard for the surgical management of upper tract transitional cell cancer

Laparoscopic nephroureterectomy for upper tract TCC still remains somewhat controversial. Unlike laparoscopic radical nephrectomy, which has become widely accepted, LNU is still in its earliest stages. Although there are obvious benefits for the patient who has LNU--less pulmonary complications, less postoperative discomfort, a shorter hospital stay, a better cosmetic result, and a brief convalescence--there are significant concerns. The longer operative time creates a negative financial and professional inducement to learn this technique. Operative times need to fall into the 4-hour range or less to make the procedure cost-effective. Analysis of the efficacy of laparoscopic nephroureterectomy as a curative treatment modality is important. In the short-run, LNU seems to provide similar results to open nephroureterectomy for upper TCC. Although concerns over port site seeding, bladder recurrence, and intraperitoneal seeding have been voiced, these problems have not occurred. The higher incidence of local recurrence noted in the authors' series, however, is of concern and remains an unsettled issue. Despite these local recurrences, the overall cancer survival for a given grade and stage of upper tract TCC seem to be similar to survivals recorded after open nephroureterectomy. Still, the number of LNU cases remains small, and follow-up is brief. These patients need to be monitored closely, with follow-up CT scans over the next decade. The authors believe that there are still several significant hurdles standing in the path of LNU before it can become a widely accepted procedure. Issues of cost, training, and long-term efficacy must be answered definitively. To obtain these types of data, it will be necessary to create a multi-institutional, cooperative study to obtain sufficient numbers of patients with a more than 5-year follow-up on which to base future recommendations.

Evaluation of a chronic indwelling prototype mesh ureteral stent in a porcine model

OBJECTIVES

Ureteral stents all share one general goal, drainage, and one major drawback, irritative symptoms in the kidney and bladder. In an effort to preserve drainage while minimizing irritation, a lightweight, self-expanding mesh stent was designed. Herein, we compare the in vivo tissue reaction and flow characteristics of the mesh stent to a standard 7F double-pigtail polyurethane stent.

METHODS

Eight female Yucatan minipigs had bilateral stents placed: a mesh stent on one side and a standard 7F stent on the opposite side. Imaging and flow measurements were obtained in 4 pigs at 1 week and in another 4 pigs at 6 weeks. Following this procedure, the stents were removed, and the kidneys, ureters, and bladder were harvested en bloc for a blinded histopathologic analysis.

RESULTS

The degree of stent-related tissue reactivity was low for both stents and appeared similar for the ureter and bladder. Overall, the mesh stent resulted in a decrease in inflammation along the urinary tract at 1 week, but this result was statistically insignificant (P = 0.55). Flow rate through the mesh stent tended to be greater than for the polyurethane stent both at 1 week and at 6 weeks.

CONCLUSIONS

Overall, the mesh stent appeared to be well tolerated and provided for excellent flow.

Laparoscopic augmentation cystoplasty with different biodegradable grafts in an animal model

PURPOSE

Recently a variety of biodegradable organic materials have been used for bladder wall replacement. We sought to study the effectiveness of 4 different types of biodegradable materials for bladder augmentation using laparoscopic techniques.

MATERIALS AND METHODS

Thirty one minipigs underwent successful transperitoneal laparoscopic partial cystectomy and subsequent closure (6 control) or patch augmentation (25): porcine bowel acellular tissue matrix (ATM) (6), bovine pericardium (BPC) (6), human placental membranes (HPM) (6) or porcine small intestinal submucosa (SIS) (7). An intracorporeal suturing technique with the EndoStitch device (U.S. Surgical, Norwalk, CT) and Lapra-Ty clips (Ethicon, Enodsurgery Inc. Cincinnati, OH) was used to anastomose the graft to the bladder wall. Postoperatively, a urethral catheter was left for one week. Bladders were evaluated by cystoscopy at 6 and 12 weeks and harvested at 12 weeks.

RESULTS

Grafts remained in place in all groups except for the BPC group, where all grafts failed to incorporate. For the ATM and SIS groups, at 6 weeks, there was mucosal coverage of the grafts without evidence of encrustation. In the control group, at 12 weeks, the bladder capacity was 23% less than preoperatively. In the ATM, HPM and SIS groups, at 12 weeks, the bladder capacities were larger than preoperatively by 16%, 51% and 43% respectively; also the grafts had contracted to 70%, 65%, and 60% of their original sizes, respectively. Histologically, there was patchy epithelialization of ATM and SIS grafts with a mixture of squamoid and transitional cell epithelia. The graft persisted as a well-vascularized fibrous band in HPM, ATM, and SIS without evidence of significant inflammatory response.

CONCLUSION

A laparoscopic technique for partial bladder wall replacement using a free graft is feasible. The biodegradable grafts of ATM, HPM and SIS are tolerated by host bladder and are associated with predominantly only mucosal regeneration at 12 weeks post-operatively.

Flexible ureteroscopes: a single center evaluation of the durability and function of the new endoscopes smaller than 9Fr

PURPOSE

Flexible ureteroscopes smaller than 9Fr are widely used in endourology. We systematically evaluated the functional durability of these instruments in the clinical setting.

MATERIALS AND METHODS

We performed ureteronephroscopy 92 consecutive times in 84 patients at our hospital using a flexible Storz model 11274AA,double dagger Circon-ACMI model AUR-7, section sign Wolf model 7325.172 parallel and Olympus model URF/P3 ureteroscope paragraph sign. Preoperatively and postoperatively we evaluated all flexible ureteroscopes for luminosity, irrigant flow at 100 mm. Hg, number of broken image fibers and active deflection range. During the procedure a record was kept of the duration that the endoscope remained in the urinary tract, average irrigation pressure, method of insertion, various devices used within the working channel, need for lower pole access, and surgeon overall impression of visibility and maneuverability.

RESULTS

The luminosity and irrigant flow of all endoscopes remained relatively unchanged during consecutive applications, while active deflection deteriorated 2% to 28%. Endoscopes were used for an average of 3 to 13 hours before they needed repair. The most fragile part of these instruments was the deflection unit.

CONCLUSIONS

Small diameter flexible ureteroscopes are effective for diagnosing and treating upper urinary tract pathology but improved durability is required. Currently they represent a highly effective but high maintenance means of achieving retrograde access to the ureter and kidney with a need for repair after only 6 to 15 uses.

Laparoscopic versus open radical nephrectomy: a 9-year experience

PURPOSE

The laparoscopic approach for renal cell carcinoma is slowly evolving. We report our experience with laparoscopic radical nephrectomy and compare it to a contemporary cohort of patients with renal cell carcinoma who underwent open radical nephrectomy.

MATERIALS AND METHODS

From 1990 to 1999, 32 males and 28 females underwent 61 laparoscopic radical nephrectomies for suspicious renal cell carcinoma. Clinical data from a computerized database were reviewed and compared to a contemporary group of 33 patients who underwent open radical nephrectomy for renal cell carcinoma.

RESULTS

Patients in the laparoscopic radical nephrectomy group had significantly reduced, estimated blood loss (172 versus 451 ml., p <0.001), hospital stay (3.4 versus 5.2 days, p <0.001), pain medication requirement (28.0 versus 78.3 mg., p <0.001) and quicker return to normal activity than patients in the open radical nephrectomy group (3.6 versus 8.1 weeks, p <0.001). The majority of laparoscopic specimens (65%) were morcellated. Operating time and cost were higher in the laparoscopic than the open nephrectomy group. Average followup was 25 months (range 3 to 73) for the laparoscopic and 27.5 months (range 7 to 90) for the open group. Renal cell carcinoma in 3 patients (8%) recurred in the laparoscopic group versus renal cell carcinoma in 3 (9%) in the open group. When stratified patients with tumors larger than 4 to 10 cm. experienced similar benefits and results as patients with tumors less than or equal to 4 cm. To date there have been no instances of trocar or intraperitoneal seeding in the laparoscopic radical nephrectomy group.

CONCLUSIONS

Laparoscopic radical nephrectomy, although technically demanding, is a viable alternative for managing localized renal tumors up to 10 cm. It affords patients with renal tumors an improved postoperative course with less pain and a quicker recovery while providing similar efficacy at 2-year followup for patients with T1 and T2 tumors.

Laparoscopic nephrectomy and nephroureterectomy for renal and upper tract transitional cell cancer

The best management for renal tumors is surgical excision. The laparoscopic technique of radical or total nephrectomy for renal cell carcinoma and radical nephroureterectomy for transitional cell carcinoma is rapidly gaining momentum as an effective method of extirpative surgery. The transperitoneal and retroperitoneal approach to either of these procedures is proving to be equally effective to open surgery with respect to tumor removal, providing similar disease-free rates. Laparoscopic surgery leads to a significantly lower intraoperative blood loss, postoperative analgesic requirement, and quicker convalescence. Presently the only drawbacks to laparoscopic surgery are longer operative times and higher costs. Fortunately, these factors are slowly approaching those of open surgery because of increased experience, improved instrumentation, and modification of the surgical technique.

Survey of neuromuscular injuries to the patient and surgeon during urologic laparoscopic surgery

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.

Laparoscopic nephropexy: long-term follow-up--Washington University experience

BACKGROUND AND PURPOSE

Recently, laparoscopy has been reported as a minimally invasive approach for performing nephropexy in patients with symptomatic nephroptosis. Herein, we report our long-term follow-up of patients undergoing laparoscopic nephropexy for this indication.

PATIENTS AND METHODS

Fourteen women presenting with right flank pain and radiologically documented nephroptosis underwent transperitoneal laparoscopic nephropexy. The hospital data were evaluated for operative time, time to oral intake, time to ambulation, amount of parenteral analgesics, and hospital stay. Pain analog scores and postoperative questionnaires were used to assess the long-term postoperative recovery of the patients.

RESULTS

The average operative time was 4.1 hours (range 2.5-6.5 hours). The patients resumed oral intake an average of 16.5 hours (range 15-48 hours) postoperatively. Analgesic requirements averaged 37 mg of morphine sulfate equivalent (range 15-80 mg of morphine equivalent). The average hospital stay was 2.6 days (range 2-5 days). The average follow-up time for the 14 patients was 3.3 years, with an average 80% improvement in their pain (range 56%-100%). On average, the patients resumed their usual activities 6 weeks postoperatively (range 1-12 weeks).

CONCLUSION

Nephropexy can be safely and effectively accomplished laparoscopically, with durable radiographic and clinical resolution of the signs and symptoms.

Laparoscopic nephrectomy in patients with end-stage renal disease and autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD) is often characterized by end-stage renal disease (ESRD) and problems including pain, hematuria, and infection. Open nephrectomy is curative; however, the morbidity of the procedure is considerable. Between 1995 and 1998, 11 laparoscopic nephrectomies were performed on nine symptomatic patients (five men and four women) with ESRD and ADPKD. Two patients underwent a staged bilateral laparoscopic nephrectomy. All patients presented with abdominal or flank pain and an abdominal mass. Other clinical problems included hypertension in eight patients, urinary tract infections in two patients, and gross hematuria in one patient. Seven patients were receiving long-term dialysis treatment, and two patients had undergone prior renal transplantation. Patients were evaluated for preoperative and postoperative pain, analgesic use, hospital course, and convalescence. The overall average operative time was 6.3 hours, with an average estimated blood loss of 153 mL. Eight nephrectomy specimens were removed by morcellation, and three specimens were removed intact through a 7- to 12-cm incision. The average hospital stay was 3 days, and the average time to normal activity was 5 weeks. With a mean follow-up of 31 months, all nine patients reported elimination of their preoperative pain based on a pain analogue score. Six major and two minor complications occurred, including blood transfusion, a vena cavotomy, splenic cyanosis, pulmonary embolism, clotted arteriovenous fistula, and brachial plexus injury. Incisional hernias occurred in two of the three patients who underwent open removal. One patient noted improvement, and two patients noted resolution of their hypertension postoperatively. Laparoscopic nephrectomy in patients with ADPKD and ESRD offers an effective alternative to open nephrectomy to manage renal-related pain. This procedure provides the benefits of minimal intraoperative blood loss, minimal postoperative pain, brief hospital stay, and rapid convalescence.

Laparoscopic nephroureterectomy for upper tract transitional cell cancer: the Washington University experience

PURPOSE

Laparoscopic nephroureterectomy has only recently been done to treat patients with upper tract transitional cell carcinoma. We retrospectively evaluated our experience with and long-term followup of laparoscopic nephroureterectomy, compared our results to those of contemporary series of open nephroureterectomy and reviewed the literature.

MATERIALS AND METHODS

We reviewed the charts of and followed up by telephone 25 patients who underwent laparoscopic nephroureterectomy between May 1991 and June 1998, and 17 who underwent open nephroureterectomy between March 1990 and January 1997. Demographic, perioperative and followup data were compared. We performed a MEDLINE search and reviewed the literature on laparoscopic nephroureterectomy for upper tract transitional cell carcinoma.

RESULTS

Laparoscopic nephroureterectomy required twice the operating time of open nephroureterectomy (7.7 versus 3.9 hours). However, patients who underwent the laparoscopic procedure had a 74% decrease in analgesia requirements (37 versus 144 mg. morphine sulfate equivalent), a 63% shorter hospital stay (3.6 versus 9.6 days) and a 72% more rapid convalescence (2.8 versus 10 weeks). Subsequent bladder transitional cell carcinoma and overall cancer specific survival were similar at a mean followup of 2 years. There was no sign of trocar site or peritoneal seeding after laparoscopic nephroureterectomy.

CONCLUSIONS

Although laparoscopic nephroureterectomy is a longer operation, it has the same efficacy and is better tolerated by patients than open nephroureterectomy for upper tract transitional cell carcinoma. As operating time decreases due to surgeon experience and the recent development of hand assisted laparoscopy, laparoscopic nephroureterectomy may soon become the procedure of choice for the ablative management of upper tract transitional cell carcinoma.

Clinical effectiveness of new stent design: randomized single-blind comparison of tail and double-pigtail stents

BACKGROUND AND PURPOSE

Stent morbidity appears to be secondary to lower urinary tract irritation. In an effort to decrease stent morbidity, a "one size fits all" Tail stent (Microvasive [Boston Scientific] Natick, MA) was developed with a 7F proximal pigtail and 7F shaft which tapers to a lumenless straight 3F tail.

PATIENTS AND METHODS

We randomized 60 patients in a single-blind fashion to a 7F tail stent or 7F double-pigtail Percuflex stent. Patients were evaluated at the time of stent removal and 2 weeks later with a standardized questionnaire assessing: irritative lower tract symptoms individually and on a total scale of 0 (no symptoms) to 30 (worst symptoms), obstructive lower tract symptoms (on a total scale of 0-20), and upper tract irritative symptoms (on a total scale of 0-10).

RESULTS

Patient age, weight, and height were similar in the two groups. Complications, including fever, urinary tract infections, emergency room visits, and the need for antispasmodics and pain medication, also demonstrated no significant difference. At the time of stent removal, patients who received a tail stent had significantly less urinary frequency and a statistically significant (21%) decrease in overall irritative voiding symptoms (12.2 v 15.4; p = 0.048). Two weeks after stent removal, the total irritative voiding symptoms was markedly decreased in both groups (7.1 in the Tail v 5.3 in the double-pigtail group; p = 0.15). Obstructive bladder and flank symptoms were not significantly different in the two stent groups, either at the time of stent removal or at 2 weeks after removal.

CONCLUSION

In this randomized, single-blind study, the 7F Tail stent produced significantly less irritative symptoms than did the standard 7F double-pigtail stent. Obstructive symptoms tended to be less with the new stent, while flank symptoms were similar.

Laparoscopic midsagittal hemicystectomy and replacement of bladder wall with small intestinal submucosa and reimplantation of ureter into graft

BACKGROUND AND PURPOSE

A variety of biodegradable organic materials have been used for bladder wall replacement. In some instances, partial replacement has been done using laparoscopic reconstructive techniques. However, to date, this activity has been limited to small patches. Herein, we present the initial experience with laparoscopic sagittal hemicystectomy and the use of laparoscopic reconstructive techniques to replace half of the bladder with small-intestinal submucosa (SIS) and to reimplant the ureter into SIS.

MATERIALS AND METHODS

Six female minipigs (20-25 kg) underwent transperitoneal laparoscopic sagittal hemicystectomy; the excised bladder wall was replaced with a 5 x 15-cm patch of SIS (Cook Biotechnology, Spencer, IN). The ipsilateral ureter was reimplanted through a small incision in the graft and secured with two sutures. Cystoscopy and cystometrograms were performed under general anesthesia preoperatively and at 6 and 12 weeks postoperatively. Tissues were harvested at 12 weeks.

RESULTS

The procedure was successful in six animals (left three, right three). During cystoscopy at 12 weeks, the area of the graft was not distinguishable from normal mucosa. Cystometrograms revealed maintenance of volume and compliance, with volumes of 338, 343, and 369 mL and intravesical leak-point pressures of 37, 59, and 39 cm H2O at 0, 6, and 12 weeks, respectively. Antegrade ureterograms demonstrated extrinsic obstruction, minimal (two), moderate (three), or complete (one), at the ureterovesical junction. The kidney associated with the completely obstructed ureter was grossly hydronephrotic at sacrifice. Histologically, patchy epithelialization of the graft with a mixture of squamoid and mature transitional-cell epithelium was found.

CONCLUSIONS

Laparoscopic hemicystectomy with replacement of the bladder wall and implantation of the ureter into the SIS graft is a feasible procedure. Clinical application awaits improvements in the method of ureteral reimplantation and longer follow-up to assess for ingrowth of muscle and nerve fibers.

Laparoscopic bladder neck suspension fails the test of time

PURPOSE

Initial reports on laparoscopic bladder neck suspension have suggested success rates similar to those of traditional bladder neck suspension. We compare long-term success rates of laparoscopic and transvaginal Raz bladder neck suspension.

MATERIALS AND METHODS

A total of 100 patients with anatomical stress urinary incontinence underwent extraperitoneal laparoscopic bladder neck suspension with securing of the endopelvic fascia to Cooper's ligament (58, laparoscopy group) or transvaginal Raz bladder neck suspension (42, transvaginal group). Patients were evaluated by chart review and telephone questionnaire to determine whether they had urinary incontinence.

RESULTS

The 2 groups were similar in terms of age, mean body mass index, preoperative bladder capacity and post-void residual. Mean followup was 45 months (range 14 to 71) in 50 laparoscopy group (86%) and 59 months (range 35 to 72) in 29 transvaginal group (70%) patients. Only 15 of 50 laparoscopy group (30%) and 10 of 29 transvaginal group (35%) patients were completely continent at followup. There was no statistically significant difference in the success rates for the 2 groups. Mean time to failure for both groups was 18 to 24 months.

CONCLUSIONS

With long-term followup laparoscopic bladder neck suspension demonstrated poor success rates similar to other minimally invasive surgical therapies for stress urinary incontinence. Any new surgical technique for treatment of stress urinary incontinence should have a mean followup of more than 2 years to determine true clinical efficacy.

Is the laparoscopic approach justified in patients with xanthogranulomatous pyelonephritis?

OBJECTIVES

Xanthogranulomatous pyelonephritis (XGP) is an atypical form of chronic renal infection. The treatment of choice is open nephrectomy, which is challenging, given the extent of the disease and the not uncommon involvement of the renal hilum and contiguous structures. We compared our experience with laparoscopic nephrectomy for histologically confirmed XGP with the open approach.

METHODS

Review of all nephrectomy specimens at Washington University School of Medicine from July 1990 to March 1998 disclosed 9 patients with a pathologic diagnosis of unilateral XGP, of whom 5 patients underwent laparoscopic nephrectomy and 4 underwent open nephrectomy. XGP was suspected preoperatively in 56% of the patients.

RESULTS

For the laparoscopic group, the average operating room time was 360 minutes, average blood loss was 260 mL, and complications occurred in 60% of patients (1 conversion to open, 1 ileus, 1 pulmonary embolus). For the open group, the average operating room time was 154 minutes, average blood loss was 438 mL, and there were no complications. Both groups were similar regarding time to oral intake, analgesia requirement, hospital stay, and time to complete recovery.

CONCLUSIONS

Our early experience demonstrates that the benefits of laparoscopic nephrectomy, at present, do not extend to patients with XGP. Conventional open surgery is quicker, associated with fewer complications, and results in a similar use of analgesics, hospital stay, and recovery time.

Laparoscopic exploration in the management of retroperitoneal masses

BACKGROUND AND OBJECTIVES

The isolated finding of a retroperitoneal mass (RM) often represents a diagnostic challenge. Image-guided biopsy is frequently inadequate for diagnosis. With increasing experience, the use of laparoscopy for exploration of an indeterminate RM may provide a minimally invasive alternative to open exploration. Herein, we present a retrospective review of our initial four laparoscopic explorations, comparing our experience to four contemporary open explorations for an RM.

PATIENTS AND METHODS

From July 1995 to January 1998, four patients, aged 50 to 62 years old, with an RM of undetermined etiology underwent laparoscopic exploration. Another four patients underwent open exploration at the same hospital. The medical records of these patients were reviewed.

RESULTS

The tumors were smaller in the laparoscopic group, averaging 3.7 cm (range 2-6 cm) vs 6.5 cm (range 1-10 cm) in the open group. A definitive diagnosis was obtained for all eight patients. Postoperative complications were observed in one of the laparoscopic explorations, and in three of the open explorations; there was no operative mortality. The blood loss (90 vs 440 ml), fall in hematocrit (5.1 vs 7.8%), time to resumption of a regular diet (3 vs 5 days), amount of morphine sulfate equivalents required for analgesia (128 mg vs 161 mg), time to ambulation (2.3 vs 6 days) and hospital stay (4.8 vs 6 days) were all less among the laparoscopy patients. However, the operative time was longer for the laparoscopic procedure; this time included stent placement and patient repositioning in addition to the time for laparoscopic excision of the mass (7.8 vs 4.3 hours).

CONCLUSION

Laparoscopic exploration appears to be a viable alternative to open exploration in patients presenting with a retroperitoneal mass. It is as effective as an open procedure and provides benefits with regard to patient morbidity and convalescence. However, operative time for this laparoscopic procedure is lengthy.

Mechanism of ureteral stent flow: a comparative in vivo study

BACKGROUND AND OBJECTIVES

The flow characteristics of ureteral stents have yet to be clearly defined. In this study, flow mechanics were studied in several silicone-based stents including 4.8F, 7F, and 10.3F pigtail; 7F Tower; and a prototype mesh stent.

MATERIALS AND METHODS

Forty-five female Yucatan minipigs underwent bilateral laparoscopic occlusion of their renal vessels to stop urine production. A nephrostomy tract was established by retrograde puncture. A stent was placed in the ureter, and three measurements were taken with flow from a bag of irrigant 20 cm above the kidney: stent occluded with a guidewire (extraluminal flow), stent unobstructed (total flow), and laparoscopically placed extraureteral ligature (luminal flow).

RESULTS

Luminal flow and, to a lesser extent, total flow appeared to increase as the internal and external diameters of the stent increased. The Tower stent, which had no sideholes, had much lower flow rates in all categories, while the prototype mesh stent showed greater total flow compared with the other stents. Extraluminal flow did not increase with stent size greater than 7F.

CONCLUSIONS

Luminal flow, but not extraluminal flow, increased with an increase in the internal diameter of the stent. In general, the least favorable flow occurred with a Tower stent, which had the smallest internal diameter. The greatest flow was seen with the prototype mesh stent.

Laparoscopic replacement of urinary tract segments using biodegradable materials in a large-animal model

OBJECTIVE

We elected to evaluate laparoscopic segmental bladder and ureteral replacement with free biodegradable graft materials in a large-animal model.

MATERIALS AND METHODS

In 18 Yucatan minipigs, a 1.5- to 2.8-cm segment of the upper ureter was excised. In 15 study animals, the ureter was laparoscopically replaced: by a stinted (6F double-J stent) tube graft made of acellular matrix (AMX) prepared from minipig ureters (MUMX) in 6 animals, acellular matrix prepared from domestic pig ureters (DUMX) in 3, and small-intestinal submucosa (SIS) in 6. In 3 control animals, the ureteral gap was bridged only by an indwelling stent. The stent was removed at 6 weeks, and retrograde ureteropyelography was performed preoperatively and at 8 and 12 weeks postoperatively, when animals were sacrificed. In 18 Yucatan minipigs, 3 x 3-cm bladder dome segments were laparoscopically replaced: by acellular matrix prepared from minipig small bowel (MBMX) in 6 animals, and SIS in 6 animals. The bladder was closed primarily in 6 control animals. Bladder capacity was assessed preoperatively and at 6 and at 12 weeks, when the animals were sacrificed.

RESULTS

The average operating time for ureteral replacement was 187 (range 105-360) minutes. At 12 weeks, all animals had complete obstruction at the level of the replacement, with fibrosis +/- bone formation at the level of the stricture. For the bladder replacement groups, the average operating time was 147 (range 85-200) minutes. At 12 weeks, the bladder capacity was 60% of the preoperative capacity in the control group, 118% in the MBMX group, and 142% in the SIS group. Histologic examination showed regeneration of urothelium and some muscle with both MBMX and SIS.

CONCLUSIONS

We were able to develop a reliable laparoscopic technique for both segmental ureteral and partial bladder replacement in a porcine model. With AMX and SIS replacement, regeneration of urothelium occurred in both ureter and bladder. However, functional replacement was successful only in the bladder.

Laparoscopic nephrectomy for renal cell cancer: evaluation of efficacy and safety: a multicenter experience

OBJECTIVES

Although laparoscopic radical nephrectomy is a safe and minimally invasive alternative to open surgery, the long-term disease-free outcome of this procedure has not been reported. We evaluated our experience with the laparoscopic management of renal cell carcinoma to assess the clinical efficacy of this surgical modality.

METHODS

Between February 1991 and June 1997, 157 patients at five institutions were retrospectively identified who had clinically localized, pathologically confirmed, renal cell carcinoma and had undergone laparoscopic radical nephrectomy. Operative and clinical records were reviewed to determine morbidity, disease-free status, and cancer-specific survival. Of the patients followed up for at least 12 months (n = 101), 75% had an abdominal computed tomography scan at their last visit.

RESULTS

The mean age at surgery was 61 years (range 27 to 92) and all patients were clinical Stage T1-2,NO,MO. Fifteen patients (9.6%) had perioperative complications. During a mean follow-up of 19.2 months (range 1 to 72; 51 patients with 2 years or more of follow-up), no patient developed a laparoscopic port site or renal fossa tumor recurrence. Four patients developed metastatic disease, and 1 patient developed a local recurrence. The 5-year actuarial disease-free rate was 91%+/-4.8 (SE). At last follow-up, there were no cancer-specific mortalities.

CONCLUSIONS

The laparoscopic surgical management of localized renal cell carcinoma is feasible. Short-term results indicate that laparoscopic radical nephrectomy is not associated with an increased risk of port site or retroperitoneal recurrence. Longer follow-up is necessary to compare long-term survival and disease-free rates with those of open surgery.

Retroperitoneal and pelvic extraperitoneal laparoscopy: an international perspective

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%.

Adult endopyelotomy: impact of etiology and antegrade versus retrograde approach on outcome

PURPOSE

We evaluate our experience with endopyelotomy for ureteropelvic junction obstruction by stratifying the results of an antegrade versus a retrograde approach for primary, secondary, calculi related, high insertion and impaired renal function related obstruction, individually.

MATERIALS AND METHODS

We retrospectively reviewed results of 149 nonrandomized patients treated for ureteropelvic junction obstruction, of whom 83 underwent antegrade percutaneous endopyelotomy using a right angle Greenwald electrode and 66 underwent retrograde endopyelotomy using a cutting balloon device. Subjective results were based on an analog pain scale, objective results on renal scan, excretory urography or Whitaker test and cost-effectiveness analysis on total treatment cost.

RESULTS

In both primary and secondary ureteropelvic junction obstruction, retrograde endopyelotomy was related to a significantly shorter operating room time and hospital stay (p < 0.05). When treating noncalculous primary ureteropelvic junction obstruction (92 patients) there was a better objective, albeit not statistically significant, success rate with antegrade endopyelotomy (89 versus 71%) but retrograde endopyelotomy was 20% more cost-effective. When treating secondary ureteropelvic junction obstruction (37 patients) there was a better objective, albeit not statistically significant, success rate (83 versus 77%) with retrograde endopyelotomy, which was 37% more cost-effective. Complication rates were higher with antegrade compared to retrograde endopyelotomy for primary and secondary ureteropelvic junction obstruction (25 versus 14% and 26 versus 0%). In 20 patients with concomitant stones endopyelotomy results were better (93 to 100% success) than for any other categories of ureteropelvic junction obstruction. Of note, endopyelotomy also provided a reasonable outcome among patients with a high insertion primary ureteropelvic junction obstruction (70% success).

CONCLUSIONS

Antegrade endopyelotomy is the preferred approach in patients with primary ureteropelvic junction obstruction and concomitant renal calculi (13.4% of cases), and may also be preferable in patients with high insertion obstruction (6.7%). For all other primary and all secondary ureteropelvic junction obstruction, antegrade and retrograde endopyelotomy is effective therapy yet retrograde endopyelotomy results in less operating room time, shorter hospital stay, fewer complications and significantly less expense to achieve the desired outcome.

Laparoscopic nephroureterectomy for upper tract transitional-cell cancer: technical aspects

Standard surgical therapy for most patients with upper tract transitional-cell carcinoma (TCC) is total nephroureterectomy with excision of an ipsilateral cuff of bladder; this procedure is performed through two separate or one long abdominal incision. The laparoscopic approach has the same goals. At Washington University, our approach has been similar to the open operation in that the procedure is performed transperitoneally and a cuff of bladder is secured. Herein, our current method for laparoscopic nephroureterectomy is described and illustrated in detail. In addition, other laparoscopic techniques for performing the nephrectomy portion and handling the distal ureter are described. Overall, this technique is still evolving as laparoscopic surgeons attempt to balance the goal of a thorough nephroureterectomy with the need to make the procedure cost effective.

Laparoscopic ureteroureterostomy using vascular closure staples in porcine model

The greatest difficulty in performing a laparoscopic pyeloplasty is the suturing of the ureteropelvic junction. The purpose of this study was to evaluate the use of nonperforating titanium vascular closure staple (VCS) clips to perform in laparoscopic ureteroureterostomy in the porcine model. Six female minipigs underwent laparoscopic transection of one of the proximal ureters at the level of the lower pole of the kidney. Ureteroureterostomy was then performed using the titanium VCS clips. The animals were evaluated at 6 and 12 weeks postureteroureterostomy with retrograde pyelography and differential creatinine clearances. At 12 weeks, the animals were euthanized, and the area of ureteroureterostomy was examined grossly and histopathologically. The technique for laparoscopic vascular clipping of the ureteroureterostomy proved to be fast and effective. Follow-up indicated that the method was successful in producing a functionally patent anastomosis. No encrustation, stone formation, or intraluminal clip was noted in any of the ureters or kidneys undergoing the ureteroureterostomy. The area of the ureteroureterostomy showed minimal fibrosis and inflammation on histopathologic examination. In this animal study, the nonperforating titanium clips facilitated the performance of a laparoscopic ureteroureterostomy.

Sonography of the female urethra

OBJECTIVE

The purpose of this study was to explore the role of sonography for women with urethral symptoms and a suspected urethral diverticulum.

SUBJECTS AND METHODS

Nineteen women with urethral symptoms underwent voiding cystourethrography (VCUG) and transvaginal, transperineal, and urethral sonography (using a catheter-based transducer). VCUGs and sonograms were evaluated for diverticula, defined on sonography by direct visualization of the neck connecting the periurethral sac with the urethral lumen. The diverticular neck, size, location, and shape were noted. Lesions revealed by sonography as not connected to the urethra were also noted.

RESULTS

Of 19 women, 14 had urethral diverticula and one had two diverticula, for a total of 15 diverticula. On sonography the diverticula ranged in diameter from 2 mm to 5 cm. Both sonography and VCUG showed 13 of the 15 diverticula. In addition, sonography revealed two infected periurethral cysts, a periurethral leiomyoma, a diffuse urethritis, and scarring or deformity of one patient's urethra from a prior diverticulectomy. On sonography, eight of the 13 diverticula wrapped around more than 50% of the urethral circumference. The neck was precisely seen (by definition) in 13 of 15 diverticula on sonography and in two of 13 diverticula on VCUG.

CONCLUSION

Sonography is useful in this group of women with urethral symptoms and suspected urethral diverticula. It provides information on the extent and location of the diverticular neck, both of which are important in surgical excision. Also, sonography provides information on lesions not connected to the urethra. Sonography may prove useful in a broader group of women with urethral symptomatology.

Endopyelotomy for high-insertion ureteropelvic junction obstruction

We assessed the results of endourologic treatment of patients with a primary ureteropelvic junction obstruction (UPJO) caused by high insertion of the ureter into the renal pelvis (HIUPJO). A total of 10 patients 15 to 76 years old with preoperatively diagnosed HIUPJO were treated. Acucise retrograde endopyelotomy was performed in eight patients and percutaneous antegrade endopyelotomy in two. A stent was left in place for an average of 5.3 weeks. The subjective success rate, based on patient questionnaire and analog pain scales, was 80% at 27 months' average follow-up. The objective success rate, based on diuretic renal scanning or Whitaker test, was 70% at 26 months' mean follow-up. Overall, 60% of the patients had both an objectively and a subjectively successful outcome. The success rate for endopyelotomy in patients with UPJO caused by high insertion is similar to that reported for endopyelotomy in patients without high insertion. High insertion is not a contraindication to endopyelotomy.

Impact of etiology of secondary ureteropelvic junction obstruction on outcome of endopyelotomy

Endopyelotomy for secondary ureteropelvic junction obstruction (UPJO) is a highly effective procedure. However, the impact of the etiology of the obstruction on the outcome of an endopyelotomy has not been defined. Herein, we review the success rates with endopyelotomy for secondary UPJO after failure of open pyeloplasty or endopyelotomy. Thirty-five adult patients with both objective and subjective follow-up were identified retrospectively who had endopyelotomy for secondary UPJO. Twenty-four patients had failed a previous open reconstruction (23) or laparoscopic Foley Y-V plasty (1). Eleven patients had failed a prior endopyelotomy. Retrograde endopyelotomy was performed using the Acucise device in 11 patients, and antegrade endopyelotomy was performed in 24 patients. Objective follow-up was obtained with diuretic renal scintigraphy (mean 14.1 months) and subjective follow-up by analog pain scales (mean 27.8 months). Objective success was defined as no obstruction on renal scintigraphy, while subjective success was used to describe a minimum of 50% resolution of symptoms. The subjective success rate of secondary endopyelotomy in the open-pyeloplasty group was 88% v 71% in the prior endopyelotomy group (P = 0.20). The objective success rate in the failed-pyeloplasty group was 71% v 55% in the prior endopyelotomy group (P = 0.40). Endopyelotomy for secondary UPJO has a good success rate. Success rates tend to be higher in patients who have failed an open pyeloplasty; however, a statistically significant difference was not seen between the two groups.

Lower caliceal stone clearance after shock wave lithotripsy or ureteroscopy: the impact of lower pole radiographic anatomy

PURPOSE

We determine whether there is a significant relationship between the spatial anatomy of the lower pole, as seen on preoperative excretory urography (IVP), and the outcome after shock wave lithotripsy or ureteroscopy for a solitary lower pole caliceal stone 15 mm. or less.

MATERIALS AND METHODS

Between January 1992 and June 1996, 34 patients with 15 mm. or less solitary lower pole stone underwent ureteroscopy with intracorporeal lithotripsy (13) or extracorporeal shock wave lithotripsy (ESWL) with a Dornier HM3 lithotriptor (21). On pretreatment IVP lower pole infundibular length and width, infundibulopelvic angle of the stone bearing calix were measured. Stone size and area were determined from an abdominal plain x-ray. A plain x-ray of the kidneys, ureters and bladder was obtained in all patients at a median followup of 12.3 and 8 months in the ureteroscopy and ESWL groups, respectively.

RESULTS

After initial therapy the overall stone-free rate was 62 and 52% in the ureteroscopy and ESWL groups, respectively. Stone-free status after ESWL was significantly related to each anatomical measurement. Infundibulopelvic angle 90 degrees or greater, and infundibular length less than 3 cm. and width greater than 5 mm. were each noted to correlate with an improved stone-free rate after ESWL. In contrast, the stone-free rate after ureteroscopy was not statistically significantly impacted by these anatomical features, although a clinical stone-free trend was identified relating to a favorable infundibular length and infundibulopelvic angle. The infundibulopelvic angle was 90 degrees or greater in 4 stone-free patients (12% overall), including 2 who underwent ureteroscopy and 2 who underwent ESWL. On the other hand, in 2 and 4 stone-free patients (18% overall) who underwent ureteroscopy and ESWL, respectively, favorable radiographic features consisted of a short, wide but acutely angulated infundibulum with the infundibulopelvic angle less than 90 degrees, and infundibular length less than 3 cm. and width 5 mm. or greater. In contrast, in 4 and 6 patients (29% overall) who underwent ureteroscopy and ESWL, respectively, all 3 radiographic features were unfavorable with the infundibulopelvic angle less than 90 degrees, and infundibular length greater than 3 cm. and width less than 5 mm. In these cases the stone-free rate was 50 and 17% after ureteroscopy and ESWL, respectively.

CONCLUSIONS

The 3 major radiographic features of the lower pole calix (infundibulopelvic angle, and infundibular length and width) can be easily measured on standard IVP using a ruler and protractor. Each factor individually has a statistically significant influence on stone clearance after ESWL. A wide infundibulopelvic angle or short infundibular length and broad infundibular width regardless of infundibulopelvic angle are significant favorable factors for stone clearance following ESWL. Conversely, these factors have a cumulatively negative effect on the stone clearance rate after ESWL when they are all unfavorable. In ureteroscopy spatial anatomy has less of a role in regard to stone clearance but it may have a negative impact when there is uniformly unfavorable anatomy.

Simultaneous bilateral percutaneous nephrolithotomy with subarachnoid spinal anesthesia

We report our experience performing simultaneous bilateral percutaneous nephrolithotomy (SBPN) in four patients with large stone burdens in both kidneys. We modified the previously described approach by combining SBPN with subarachnoid Duramorph (preservative-free morphine sulfate) in an effort to decrease postoperative discomfort and shorten the duration of hospitalization. These patients (study group) were then compared with a contemporary group of four patients with similar bilateral stone burdens who underwent staged bilateral percutaneous nephrolithotomies (PCNs) (control group). The comparison showed a marked advantage in hospital stay (4.8 days for the study group v 11 days for the control group) and postoperative narcotic requirement (27.5 mg of meperidine for the study group v 533 mg for the control group). All four patients were rendered stone free. This method of treatment for large bilateral renal calculi with the addition of subarachnoid Duramorph resulted in less postoperative discomfort, less morbidity, and a more rapid recovery than staged PCN or sandwich PCN/SWL/PCN.

Laparoscopic staging of bladder tumor: concerns about port site metastases

Since the first laparoscopic pelvic lymph node dissection (LPLND) was performed for prostate cancer, only one case of port site metastasis has been reported, an incidence of 0.1%. On the other hand, three cases of port site metastasis have been reported after laparoscopic staging of transitional-cell carcinoma (TCC) of the bladder, a reported incidence of almost 4%. Herein, we review the circumstances of these three cases and address the potential risk factors and possible preventive measures regarding LPLND and port site metastasis in patients with TCC of the bladder.

Endoscopic creation of reflux in the pig

Vesicoureteral reflux (VUR) in the animal model for experimental purposes can be created either by open transvesical or endoscopic techniques. The concept of reflux creation is the same for both techniques: incision of the roof of the intramural portion of the ureter at the 12 o'clock position. The open method has the disadvantages of requiring a cystotomy and a lengthy healing period prior to initiating a study, thereby incurring additional expense and the problem of introducing several confounding factors. The open method is unreliable because of the resolution of reflux over time. Herein, we present a simple transurethral endoscopic technique for creating VUR in pigs. This technique was successful in producing persistent Grade II or III reflux in 94% of the incised ureters.

Laparoscopic wedge resection and partial nephrectomy--the Washington University experience and review of the literature

Open partial nephrectomy is an accepted form of treatment for a variety of benign conditions and for localized renal cell carcinoma. To date, there is limited experience with the clinical application of laparoscopic partial nephrectomy and wedge resection for benign and malignant disease of the kidney. Herein, we report our clinical experience with laparoscopic partial nephrectomy and a review of the current literature. Twelve patients (27-81 years) have undergone laparoscopic wedge resection (3) or attempted polar partial nephrectomy (9) since 1993. In the group of 12 patients, 5 had a mass suspicious for a malignancy, 4 patients had symptomatic polar calyceal dilation with or without stone disease, and 3 patients had an atrophic or hydronephrotic upper pole moiety. Among the patients in the polar nephrectomy group, a third were converted to an open procedure. The remaining 6 patients had a mean operative time of 6.5 hours (5.7-8.3 hours). These patients resumed their oral intake on average 0.8 days postoperatively. In the 2 patients with a mass, the final pathology was oncocytoma (1), and xanthogranulomatous reaction in a renal cyst (1). Postoperative complications included a nephrocutaneous fistula which was endoscopically fulgurated, a retroperitoneal urinoma which was percutaneously drained, and a two-day bout of ileus. The mean hospital stay was 5.3 days (2-9). Their full convalescence was completed in a mean of 4.2 weeks (2-8). Three patients underwent a wedge resection for a superficial < 2 cm mass. The average operative time in this group was 3.5 hours (2-5.4). The mean time to resuming oral intake was 0.7 days (0.3-0.7). The final pathology was oncocytoma (1), oncocytic renal cell cancer (1), and old infarction (1); none of the patients had any complications. The mean hospital stay was 2.7 days (2-4). Convalescence was completed in 4 weeks (range 1-8). Laparoscopic wedge resection and polar partial nephrectomy are feasible, albeit currently tedious techniques. While wedge excision of a < 2 cm superficial lesion is relatively straightforward and efficient, laparoscopic polar partial nephrectomy remains a difficult technique and at present remains in evolution. Further development of instrumentation to provide for a reliable, expeditious, and hemostatic partial nephrectomy is needed.

Techniques for stenting the normal and obstructed ureter

Ureteral obstruction is a common cause of urologic morbidity requiring quick and effective treatment, as prolonged obstruction can cause pain, infection, and eventual loss of renal function. Few would argue that initial drainage or bypassing of the obstruction is favorable initial management; however, urologists are often-times faced with technically difficult cases not responsive to the standard operative maneuvers. Recognizing the diversity of pathology and the potentially complicating issues, urologists should have in their armamentarium a systematic approach or algorithm for dealing with these common dilemmas, as well as an understanding of various tricks of the trade. This knowledge will prevent heightened anxiety at the time of surgery and will ensure the availability of the proper operative equipment. This article outlines an approach and discusses the obstacles and options in stenting the obstructed ureter.

Laparoscopic ablation of peripelvic renal cysts

PURPOSE

We describe and define the operative techniques, findings and results of laparoscopic ablation of peripelvic renal cysts.

MATERIALS AND METHODS

One male and three female patients, ranging in age from 35 to 59 years, underwent laparoscopic ablation of symptomatic peripelvic cysts. All patients had symptoms of ipsilateral flank pain and obstruction. One patient had an episode of pyelonephritis before detection of the cyst, and 2 patients had concomitant stones within the obstructed system. Cysts ranged in size from 4 to 6 cm. Dissection was uniformly complex because of the depth to which the cyst extended into the renal parenchyma and the overlying renal vessels and collecting system.

RESULTS

Operative times ranged from 315 to 390 minutes (mean 338 minutes). The average length of hospital stay was 2.75 days (range 2 to 4 days). Three of 4 patients (75%) had resolution of their symptoms and collecting system obstruction. One patient, the only case of a retroperitoneal approach, had recurrence of her symptoms and cyst 2 months after the operation and required open surgical repair.

CONCLUSIONS

Laparoscopic ablation of peripelvic cysts is a challenging yet feasible procedure. Because of the medial location of these cysts, a transperitoneal approach may be preferable to retroperitoneal access alone.

Incisional hernia after laparoscopic nephrectomy with intact specimen removal: caveat emptor

PURPOSE

We report 5 cases of postoperative incisional hernia after laparoscopic nephrectomy with intact removal of the specimen.

MATERIALS AND METHODS

During the last 5 years 29 patients underwent laparoscopic nephrectomy with intact removal of the resected specimen due to a large kidney and/or malignancy. Of these 29 patients 5 had a postoperative incisional hernia at the site of intact removal, including 3 with renal tumors and 2 with large polycystic kidneys due to adult onset autosomal dominant polycystic kidney disease. The records of these patients were reviewed to determine any specific factors that might relate to the development of this complication.

RESULTS

An incisional hernia developed at the wound site in 5 patients (17%) 41 to 73 years old (mean age 53.4). Average body mass index for the patients was 34.2 (range 26 to 47). Average weight and size were 542 gm. and 20.3 x 10.3 cm., respectively, for the 3 resected malignant specimens and 1,975 gm. and 23.8 x 16.5 cm., respectively, for the 2 benign kidneys. A transverse lower flank muscle cutting incision (average 10.4 cm.) was performed to remove the resected kidney. Incisional hernias appeared after an average of 6.6 weeks postoperatively. Risk factors for a postoperative hernia included obesity in 80% of the patients, chronic renal insufficiency due to autosomal dominant polycystic kidney disease in 40%, postoperative pulmonary complication in 40% and metastatic cancer in 20%.

CONCLUSIONS

Our experience has led us to avoid a lower flank port connecting incision for specimen removal. Instead we changed to a midline or subcostal incision in these patients. In addition, we believe that with the availability of the impermeable organ entrapment sacks there is less need for intact specimen removal even for renal tumors. Currently large benign kidneys (autosomal dominant polycystic kidney disease) are morcellated in situ to a suitable size for entrapment, while renal tumors are entrapped and morcellated directly. Presently our only indication for intact removal is in the case of a renal pelvic or caliceal transitional cell cancer.

Effect of mineral oil on porcine urothelium

Mineral oil has been used to facilitate ureteral stone extraction and to treat selected patients with infected residual urine. The purpose of this study was to evaluate the effect of mineral oil on the urothelium. Twelve adult female farm pigs underwent bilateral ureteral catheter placement under general endotracheal anesthesia. Retrograde pyelograms were performed and the ureteral diameters measured. Using a randomization protocol, six animals underwent injection of 10 mL of normal saline into one ureteral catheter and 50 mL of normal saline instillation into the bladder. In the remaining six animals, 10 mL of mineral oil was injected into one ureteral catheter and 50 mL of mineral oil into the bladder. The instillation was maintained for 30 minutes, and then the catheters were removed. One week later, under general endotracheal anesthesia, cystoscopy and retrograde pyelography were performed to measure the diameter of the ureters, and the animals were euthanized. The bladder, ureters, and kidneys were harvested for macroscopic and histopathologic evaluation. There was no significant difference in the diameter of the ureters injected with normal saline, the uninjected ureters, or the mineral oil-injected ureters. The bladders, ureters, and kidneys were grossly normal in all animals. No significant histopathologic changes were noted in the ureteral or bladder urothelium or the renal parenchyma in the animals injected with mineral oil. In conclusion, the instillation of mineral oil within the urinary tract does not have any significant long-term functional or histopathologic effect on the urothelium.

Laparoscopic pneumodissection: results in initial 20 patients

BACKGROUND

The efficiency of laparoscopic procedures has been hindered by a lack of instrumentation for blunt tissue dissection. We evaluated here the efficacy of a new 5-mm laparoscopic dissecting instrument, a pneumodissector. This instrument allows the surgeon to use short bursts of high-pressure carbon dioxide to bluntly dissect fatty tissue.

STUDY DESIGN

In 20 patients undergoing a variety of laparoscopic procedures, a 5-mm laparoscopic pneumodissector was used. Subjective assessment of the efficacy of the instrument was recorded. In addition, acid-base changes were measured by blood gas determination, and serum chemistries were obtained before, during, and after the procedure.

RESULTS

The pneumodissector enhanced dissection of the kidney, ureter, and major blood vessels and shortened the operative time for laparoscopic nephrectomy. Although statistically significant changes in acidbase values occurred with use of the pneumodissector, these changes were not clinically significant and were no different than what is normally seen during carbon dioxide pneumoperitoneum.

CONCLUSIONS

Laparoscopic pneumodissection is a safe and efficacious technique for rapid blunt tissue dissection.

Laparoscopic adrenalectomy for solitary metachronous contralateral adrenal metastasis from renal cell carcinoma

PURPOSE

We report our experience with laparoscopic adrenalectomy for malignant adrenal disease.

MATERIALS AND METHODS

Between June 1995 and January 1996, 2 patients with a solitary metachronous contralateral adrenal metastasis from renal cell cancer were evaluated. Both patients had undergone radical nephrectomy for localized renal cancer 5 years previously. Laparoscopic transperitoneal adrenalectomy was performed.

RESULTS

The laparoscopic procedures required 2.5 and 4.3 hours. Hospital stay was 3 and 4 days. The specimens weighed 98 and 81 gm. All surgical margins were free of metastatic clear cell cancer. Both patients were begun on prednisone and fludrocortisone replacement therapy. One patient experienced an increase in creatinine, which has since stabilized at 3.0 mg/dl. Neither patient had recurrent cancer at 11 and 16 months of followup.

CONCLUSIONS

Laparoscopic adrenalectomy for metastatic renal cell cancer was performed successfully in 2 patients. However, the short-term benefits to the patient of earlier ambulation, decreased pain, minimal incisions and shortened convalescence must be weighted against the as yet unknown long-term (5 years) results.

Endourologic management of ureterosigmoidostomy anastomotic stricture

A 47-year-old woman presented with a stricture of a ureterosigmoid anastomosis. After through-and-through access had been established from a nephrostomy tract to the anus, an Acucise cutting balloon catheter was positioned retrograde and used to incise the strictured area. Twelve months postoperatively, the patient is doing well. Monitoring for colon adenocarcinoma continues.

Preoperative assessment of ureteropelvic junction obstruction with endoluminal sonography and helical CT

OBJECTIVE

Our objective was to compare the value of endoluminal sonography with the value of helical CT in the preoperative assessment of crossing vessels in patients with ureteropelvic junction (UPJ) obstruction.

SUBJECTS AND METHODS

Thirteen patients with UPJ obstruction underwent contrast-enhanced helical CT with multiplanar reformations and endoluminal sonography. Imaging preceded surgery for UPJ repair. On imaging, vessels were considered significant if greater than or equal to 2 mm in diameter and within 1 cm of the UPJ.

RESULTS

Three patients had no crossing vessels revealed by either study. On sonography, another patient had a vessel revealed with a diameter that varied between 1.3 and 2.2 mm; on CT no correlate was detected. The remaining nine patients had vessels revealed by both techniques. On CT, four patients had two vessels revealed and five patients had single vessels revealed for a total of 13 vessels revealed by CT. On sonography, five patients had two vessels revealed and five patients had single vessels revealed. Thus, 15 vessels were revealed by sonography. Both arteries and veins were revealed anterior, posterior, and medial to the UPJ; no lateral vessels were seen. Four patients underwent laparoscopy, during which the absence, presence, and location of vessels were found to correlate with sonography and helical CT.

CONCLUSION

Endoluminal sonography and helical CT were similar in revealing crossing vessels in patients with UPJ obstruction.

Recent advances in laparoscopic partial nephrectomy: comparative study of electrosurgical snare electrode and ultrasound dissection

Although technically feasible, laparoscopic partial nephrectomy (LPN) using conventional instrumentation presents the intraoperative challenge of hemostasis, creating a flush (i.e., precise guillotine) incision, and closure of the collecting system. In an effort to resolve these technical problems, we used a unique electrosurgical snare electrode (ESE) in combination with an ERBE electrosurgical generator and compared its effectiveness with that of two ultrasonic dissectors (Cavitron Ultrasonic Surgical Aspirator [CUSA] and harmonic scalpel [HS]) in performing LPN. Twelve female minipigs underwent right lower-pole LPN using one of the aforementioned modalities. Six weeks later, in the same animals, a left lower-pole LPN was performed using the same device, thereby providing an acute and chronic renal remnant to examine. The animals were harvested, and transverse and perpendicular histologic sections were prepared of the cut surface of each specimen. The weights of the LPN specimens and the remaining kidney were also recorded. The time required for partial nephrectomy, degree of hemostasis (i.e., blood loss), ease of excising the targeted tissue, changes in renal function, tissue reactivity, and depth of damage to the surface of the remaining renal parenchyma were measured for each device. All 12 procedures were successful using the ultrasonic dissection, and 11 procedures were successful using the ESE. The ESE was significantly faster than the two forms of ultrasonic dissection (p < 0.0001) and produced less intraoperative bleeding (P = 0.002). Both forms of ultrasonic energy produced significantly deeper parenchymal injury in the acute surgical specimen (P = 0.03) and more parenchymal fibrosis and chronic inflammation in the chronic surgical specimens (P = 0.007) than the ESE. None of the animals exhibited any extravasation from the incised collecting system when studied by retrograde pyelography 6 weeks postoperatively at the time of left LPN and harvest. The function of the renal remnant was consistent with the size of the partial nephrectomy specimen. No hypertension developed in any of the study animals. Our results using a unique electrosurgical snare probe show it to have potential advantages as a rapid, hemostatic method for performing a partial nephrectomy. We believe that this instrument may represent an important tool for performing nephron-sparing surgery via an open or laparoscopic approach. Clinical trials are in progress.

Laparoscopic creation of a catheterizable cutaneous ureterovesicostomy

Nephrectomy and creation of a cutaneous ureterovesicostomy for intermittent catheterization of the bladder traditionally requires two surgical procedures performed through separate incisions. Herein we report completion of these procedures using a transperitoneal laparoscopic approach, with the ureterovesicostomy stoma created at one of the laparoscopic working ports. The clinical course was remarkable for a shortened postoperative hospitalization (48 hours) with minimal incisional pain, and an excellent long-term result with complete bladder emptying and resolution of urinary infections. Laparoscopic application of the Mitrofanoff principle for creation of a catheterizable cutaneous ureterovesicostomy combines the advantages of both, allowing optimal preservation of ureteral vascularity, minimal morbidity, and efficient bladder evacuation.