摘要:

Anin vivomodel for the study of human transitional cell carcinoma (TCC) in the urinary tract is desirable. Orthotopic xenografts are useful in order to approximate better the behavior of human tumor cellsin situ. Prior models have been described in the urinary bladder of the nude mouse and rat. We have developed the first model of implantation of human TCC in the upper urinary tract of an experimental animal. The kidneys of homozygous nude rats 4 weeks of age were inoculated with 1-5 x 106cells of the RT4 well-differentiated papillary human TCC line through bilateral flank incisions, with transparenchymal injection of tumor cells into either the collecting system (renal pelvis) or the parenchyma. The overall implantation rate was 92% (54/59 kidneys). However, implantation into the collecting system occurred in only 45% (18/45) of the group. Ligation of the ureter prior to inoculation to produce urine stasis improved the mucosal implantation rate. Despite suspect urine cytology findings in the renal pelvis injection group, no distal seeding of the urinary tract was seen. Intraparenchymal tumor growth was less differentiated and had a higher fraction of mitotic cells than mucosal tumors. Vascular and lymphatic invasion were commonly seen; however, distant metastasis was not observed. This model will prove useful in determining the role of seeding in recurrent disease and in developing less invasive modalities for the treatment of upper tract TCC.

ISSN:0892-7790    

DOI:10.1089/end.1995.9.1

年代:1995

数据来源: MAL

摘要:

The treatment options for large renal calculi are controversial. We report on our experience with 65 treatments of renal calculi>3 cm using extracorporeal Shockwave lithotripsy (SWL) monotherapy. We stratified our results according to stone and collecting system surface areas (measured by computer image analyses), stone location, and stone type. The overall success rate of SWL monotherapy was 27% at 3 months. The best stone-free rate (60%) was obtained for stones1000 mm2was only 8%. None of the cystine stones was treated successfully, whereas 80% of patients with uric acid stones became stone free. We estimated an average cost of $67,048 to render a patient with a large renal calculus stone free using SWL monotherapy. We recommend that other treatment options, such as percutaneous nephrolithotomy, be considered as first-line therapy for large renal calculi.

ISSN:0892-7790    

DOI:10.1089/end.1995.9.9

年代:1995

数据来源: MAL

摘要:

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

ISSN:0892-7790    

DOI:10.1089/end.1995.9.15

年代:1995

数据来源: MAL

摘要:

Laparoscopic nephron-sparing surgery has been limited by several factors, including problems in the control of the vascular pedicle and the management of parenchymal bleeding. In an effort to improve the efficacy of laparoscopic nephron-sparing surgery, we developed and tested several techniques to control and manage intraoperative renal bleeding while performing 30 laparoscopic anatrophic nephrolithotomies using the porcine model. Control of the renal pedicle and management of bleeding included the use of the following: (1) extracorporeally applied atraumatic vascular pedicle clamp; (2) Argon Beam Coagulator to perform the capsulotomy; (3) electrocautery scissors to perform the nephrotomy; (4) Gelfoam welded to the cut surface of the parenchyma with the argon beam coagulator; (5) Surgicel welded to the outer surface of the kidney with the Coagulator; and (6) laparoscopically applied bolster sutures to further stabilize the renal unit. All animals tolerated the procedure well and survived to their appointed date of sacrifice. We conclude that these techniques may improve the efficacy of laparoscopic renal surgery, including nephron-sparing procedures.

ISSN:0892-7790    

DOI:10.1089/end.1995.9.23

年代:1995

数据来源: MAL

摘要:

Advances in endoscopic instrumentation and techniques have expanded our armamentarium for safe and effective treatment of urethral strictures. Endoscopic incision or dilation should remain the preferred treatment for uncomplicated primary strictures. Balloon dilation can be useful in the treatment of dense strictures. Incision using laser energy has yet to provide better results than procedures employing a cold knife. As such, it would be difficult to justify the added expense of laser urethrotomy. Endoscopic placement of free skin grafts into the bed of the urethra after transurethral resection or deep incision of the stricture is a novel approach that has shown a great deal of promise. Endourethroplasty is a reasonable alternative to open urethroplasty when treating long strictures, as more than 90% of the reported patients have had a successful outcome with no recurrence. However, larger experience with this procedure is necessary to verify its efficacy and for greater acceptance. The placement of indwelling stents is another new promising treatment option. Overall short-term success rates range from 75% to 100%, but the follow-up period is short, and little is known about the long-term risks of an indwelling foreign body in the urethra. Endoscopic incision via "cutto-the-light" or "core-through" procedures is an excellent alternative in patients with obliterative strictures. Data from several centers reveal that the majority of patients gain relief of obstruction while maintaining continence and erectile potency. However, at least 25% of these patients will need further endoscopic management to maintain urethral patency.

ISSN:0892-7790    

DOI:10.1089/end.1995.9.31

年代:1995

数据来源: MAL

摘要:

The painful stimuli produced by a new generation of electrohydraulic/electromagnetic lithotripters are such that continuous infusion analgesia rather than general or regional anesthesia is appropriate. We describe our experience with continuous alfentanil infusion supplemented with intravenous bolus midazolam in caring for patients treated with an unmodified Medstone STS 1050 lithotripter. Ninety consecutive treatments using this technique averaged 63 minutes, compared with 69 minutes for 14 treatments done with general anesthesia and 88 minutes for 58 treatments done with epidural anesthesia. The stone burden, kilovoltage, and number of shocks were similar for the three groups, as was the immediate stone fragmentation rate. Only 2 of 90 patients received inadequate analgesia with the intravenous technique and required the induction of general anesthesia. Continuous-infusion analgesia appears sufficient to blunt the stimulus provided by the unmodified spark-gap lithotripters still in common use.

ISSN:0892-7790    

DOI:10.1089/end.1995.9.41

年代:1995

数据来源: MAL

摘要:

The long-term effects of extracorporeal Shockwave lithotripsy (SWL) on children treated for renal calculi are unclear. To study the effects on the immature animal, we evaluated 31 Wistar white rats that underwent right nephrectomy at 30 days of age. At 40 days of age they were divided into three groups: a control group of 10 rats that received no Shockwaves; Group I (9 rats) that received 1000 Shockwaves at 16.0 kV, and Group II (12 animals) that received 1000 shock waves at 17.2 kV. Six months later at maturity (7 months and 10 days of age), the following parameters were measured: (1) body and renal weight; (2) blood lithium, sodium, potassium, and creatinine; (3) fractional lithium, sodium, and potassium excretion; and (4) clearances of lithium and creatinine. The kidneys were studied grossly and histologically. We found no significant changes in overall animal and renal growth between the post-SWL and control groups. However, there were significant changes in renal function. The animals in Groups I and II presented significant increases in blood potassium compared with the control group. Furthermore, the 1000 x 17.2 kV group showed permanent histologic renal changes, including red cells in Bowman's capsule and glomerular congestion. The disorders caused by SWL are compatible with hyporeninemic hypoaldosteronism, inappropriately low plasma renin activity, and aldosterone deficiency. We conclude that although SWL does not affect either overall or renal growth, it may cause significant changes in renal function and permanent histologic damage.

ISSN:0892-7790    

DOI:10.1089/end.1995.9.45

年代:1995

数据来源: MAL

摘要:

Complete metabolic evaluation was performed in 21 patients with infected renal lithiasis. Patients with pure struvite stones (struvite ± carbonate apatite) were significantly less likely to have metabolic abnormalities than patients who had struvite ± carbonate apatite ± calcium oxalate (2 of 14 v 7 of 7,P= 0.0003). Urine calcium excretion was markedly higher in the mixed stone group than the pure struvite group (342 ± 98 mg/24 h v 136 ± 82 mg/24 h;P<0.0001). The differing opinions among researchers regarding the likelihood of finding metabolic abnormalities in patients with urolithiasis and infection probably reflect differences in the definitions of the populations studied. If patients with calculi containing only struvite ± carbonate apatite are evaluated, we believe that few significant metabolic abnormalities will be ident

ISSN:0892-7790    

DOI:10.1089/end.1995.9.51

年代:1995

数据来源: MAL

摘要:

Although they are rarely associated with complaints, benign renal cysts may be the cause of pain, hypertension, or other problems. Simple aspiration is rarely definitive treatment. We have had good results with three laparoscopic approaches to cyst unroofing: transperitoneal, with reflection of the colon medially or dissection through the mesocolon and direct retroperitoneoscopy. We recommend initial percutaneous aspiration with cytology study both to rule out malignancy and to identify those cysts clearly in need of unroofing.

ISSN:0892-7790    

DOI:10.1089/end.1995.9.55

年代:1995

数据来源: MAL

摘要:

A completely new combined laparoscopic cystectomy and ileal conduit technique for removal of an infiltrating bladder cancer was carried out on a 64-year-old woman. The bladder was dissected free and extracted whole through the right flank. The right ureter and a loop of intestine were withdrawn through the same incision. An ileal segment was isolated and intestinal continuity restored. The right ureter was anastomosed to one extreme of the segment that was then reintroduced into the abdomen, taken across to the left side, withdrawn with the left ureter, anastomosed extracorporeally, and reintroduced. The stoma was constructed in the left flank at the patient's request. Recuperation was unusually fast and painless, and little postoperative analgesia was required. Further experience and a two-team approach could reduce the operation time to 3 or 4 hours. We are now convinced that combining the two procedures was better for the patient, even though it prolonged the time in the operating room.

ISSN:0892-7790    

DOI:10.1089/end.1995.9.59

年代:1995

数据来源: MAL