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Biomedical subjects

R V Clayman

Publications and source records attributed to R V Clayman.

At least 145 records · Page 8Linked to original sources
PubMed1995

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

PURPOSE: The recognized form of therapy for patients with ureteral or renal pelvis transitional cell carcinoma is total nephroureterectomy with excision of the ipsilateral periureteral cuff of bladder mucosa. We report our experience with 10 patients who underwent laparoscopic nephroureterectomy for upper tract transitional cell carcinoma through July 1994 and compare them to a contemporary group of patients undergoing open nephroureterectomy for the same disease. MATERIALS AND METHODS: A total of 10 patients undergoing laparoscopic nephroureterectomy for upper tract transitional cell carcinoma was evaluated with respect to operative time, surgical specimen weight, pathological stage, postoperative analgesia requirement, interval to resume normal oral intake, postoperative recovery and results of postoperative surveillance. Of the patients 8 who underwent open surgical nephroureterectomy during a contemporary period for the same diagnosis were evaluated for the same parameters and compared to the laparoscopic group. RESULTS: Laparoscopic nephroureterectomy averaged twice as long as open nephroureterectomy. However, the laparoscopic patients resumed oral intake sooner, required less postoperative analgesia and had a shorter hospital stay compared to the open surgical group. The laparoscopic nephroureterectomy patients returned to normal activities within less than half the time (2.8 versus 6 weeks) and completely recovered 5 times more rapidly (6 weeks versus 7.4 months). CONCLUSIONS: Laparoscopic nephroureterectomy is a feasible treatment option for patients with upper tract transitional cell carcinoma. However, 2 major drawbacks to the approach persist, that is the lengthy operative time and the need for significant laparoscopic experience on the part of the surgeon.

Aged↗
PubMed1995

Laparoscopic partial nephrectomy: initial experience and comparison to the open surgical approach.

During an 18-month period, 6 laparoscopic partial nephrectomies were attempted, 4 of which were successful. The surgical technique was modified and improved between cases aided by new laparoscopic instrumentation, such as the argon beam coagulator and the 7.5 MHz. ultrasonic sector scanning system. In a retrospective comparison between laparoscopic and open partial nephrectomy, estimated blood loss was 525 ml. for the former versus 708 ml. for the latter procedure. However, operating time was more than 2 hours longer with the laparoscopic approach. The major advantages of the laparoscopic procedure appear to be a more rapid return to full diet, less postoperative pain and less requirement for parenteral narcotics. Despite the small size of this series and limited followup data, convalescence may be shortened by 4 weeks after laparoscopic partial nephrectomy. Patients with benign diseases of the kidney, especially with a duplicated collecting system, who require partial nephrectomy may be considered candidates for the laparoscopic approach. The advantages to the patient, however, may be offset by the technical demands on the surgeon.

Adult↗
PubMed1995

Subcutaneous urinary diversion utilizing a nephrovesical stent: a superior alternative to long-term external drainage?

OBJECTIVES: The use of external percutaneous nephrostomy drainage in patients with end-stage ureteral obstruction in whom ureteral stenting has failed presents significant compromises in the patient's quality of life. Toward this end, we present the initial experience in the United States with an intracorporeal nephrovesical stent. METHODS: We performed successful subcutaneous urinary diversion in 2 patients with malignant, metastatic periureteral obstruction. Both patients had previously been managed with a chronic percutaneous nephrostomy that was both painful and inconvenient. The nephrovesical stent was inserted utilizing percutaneous access to both the kidney and bladder followed by creation of a subcutaneous tunnel between the two sites. RESULTS: The nephrovesical stents are patent at 6 and 9 weeks postoperatively and both patients have had their nephrostomy tubes removed. Both patients have noted a marked improvement in their overall comfort and quality of life since the stent has been in place. CONCLUSIONS: Subcutaneous urinary diversion with a nephrovesical stent provides effective urinary drainage and may improve the quality of life of patients with malignant metastatic ureteral obstruction. Further long-term studies are needed.

Adult↗
PubMed1995

Laparoscopic pneumodissection: initial clinical experience.

OBJECTIVES: We evaluated the efficacy of a new laparoscopic dissecting instrument that fires intermittent bursts of high-pressure carbon dioxide to separate tissue along natural planes. METHODS: The pneumodissector (PD) was used in 2 patients undergoing laparoscopic procedures. Serum creatinine and bicarbonate were measured before and after the procedure, and arterial blood gases were measured before, during, and after use of the PD. Subjective assessment of the ease of dissection with the PD by the first assistant was recorded. RESULTS: Acidosis and hypercarbia were not observed with use of the PD. The PD facilitated dissection along the iliac vessels, around the kidney, and in the renal hilum. CONCLUSIONS: The PD is a feasible method for rapid, blunt dissection during laparoscopic procedures.

Adolescent↗
PubMed1995

Laparoscopic pyeloplasty for secondary ureteropelvic junction obstruction: preliminary experience.

OBJECTIVES: To identify whether laparoscopic pyeloplasty is a reasonable treatment option for secondary ureteropelvic junction (UPJ) obstruction. METHODS: Since March 1994, we have performed laparoscopic pyeloplasties for secondary UPJ obstruction on 4 symptomatic patients ranging in age from 26 to 39 years. Prior failed procedures included antegrade endopyelotomies (3) and acucise endopyelotomies (3). Two patients underwent two prior endopyelotomies. Techniques of laparoscopic reconstruction included Anderson-Hines dismembered (3) and Culp-Deweerd flap (1) procedures. Repairs were performed with interrupted and running 3.0 and 4.0 Vicryl sutures using intra-corporeal knots and Lapra-Ty absorbable suture clips. RESULTS: Average operating time was 530 minutes (range, 465 to 645), which included preoperative cystoscopic placement of an external 7 F occlusion balloon catheter into the renal pelvis and placement of an internal double pigtail ureteral stent at the conclusion of the procedure. Average blood loss was 111 cc (range, 75 to 150). All 4 patients were found to have anterior crossing vessels intraoperatively. Average postoperative hospital stay was 4 days (range, 3 to 7). All 4 patients have a patent, nonobstructed UPJ by either Whitaker test or diuretic renography at an average of 3.3 months postoperatively (range, 1 to 5). Average return to normal activity was 4.5 weeks (range, 3 to 8). Utilizing an analogue pain scale, 2 of the patients are pain-free, and the other 2 are improved (45% and 85%) at an average of 8 months (range, 2 to 12) postoperatively. One patient developed stones in the renal pelvis and required percutaneous nephrolithotomy 10 weeks postoperatively. CONCLUSIONS: Laparoscopic pyeloplasty appears to be feasible and effective, although a technically challenging operative procedure for treating secondary (postendopyelotomy) UPJ obstruction. Further clinical experience and long-term follow-up are needed.

Adult↗
PubMed1995

Washington University experience with extracorporeal shock-wave lithotripsy of pancreatic duct calculi.

OBJECTIVES: To ascertain the effectiveness and safety of extracorporeal shock-wave lithotripsy (ESWL) for pancreatic calculi. METHODS: Fourteen ESWL treatments were performed in 12 patients with chronic pancreatitis. RESULTS: Fragmentation was perceptible after 13 of 14 treatments. Subsequent endoscopic manipulation resulted in complete extraction, partial extraction, and failed extraction of the fragments after 7, 4, and 2 of the ESWL treatments, respectively. No complications occurred and no patient had pancreatitis following ESWL. At a median follow-up of 19 to 22 months, 4 patients have had complete relief of symptoms, 4 have had a decrease in both severity and frequency of pain, and 4 have had no improvement. CONCLUSIONS: ESWL is a safe and useful noninvasive adjunct in the treatment of patients with pancreatic duct calculi.

Adult↗
PubMed1995

Extracorporeal shock-wave lithotripsy of middle ureteral stones: are ureteral stents necessary?

OBJECTIVES: To ascertain whether insertion of a ureteral stent improves the outcome of middle ureteral (overlying the pelvic bone) stones treated with extracorporeal shock-wave lithotripsy (ESWL). METHODS: Thirty-three patients with middle ureteral stones were treated with ESWL at our institution between October 1991 and October 1994. Twenty-six patients were available for follow-up; 14 patients were treated with stent bypass, 8 were treated in situ, and 4 patients were treated after percutaneous nephrostomy (PCN). All patients were treated initially on an unmodified Dornier HM-3, and all but 4 patients were treated in the prone position on a modified Stryker frame. Follow-up consisted of a plain abdominal radiograph, intravenous urogram, occasionally a retrograde urogram, and a telephone interview. RESULTS: The overall stone-free rate for ESWL alone was 73%, and the efficiency quotient was 69. The stone-free rates after a single treatment for the stent bypass, in situ, and PCN groups were 71%, 63%, and 75%, respectively. Overall, 4% of patients required retreatment, 19% of patients required an auxiliary procedure, and 8% of the patients required hospital or emergency room admissions for renal colic. For stones 10 mm or greater (9), stone-free rates after one treatment for the stent bypass, in situ, and PCN groups were 33%, 33%, and 67%, respectively; for stones less than 10 mm (17), success rates were 82%, 80%, and 100%, respectively. CONCLUSIONS: Pretreatment stinting provides no advantage over in situ ESWL for middle ureteral calculi (Fisher's exact test, P = 1.0). ESWL is a reasonable initial therapy for middle ureteral stones less than 10 mm.

Adult↗
PubMed1995

Percutaneous electrovaporization of upper tract transitional cell carcinoma in patients with functionally solitary kidneys.

OBJECTIVES: We present the first reported experience using percutaneous electrovaporization with both a rollerball and the VaporTrode electrode of large upper tract transitional cell carcinoma (TCC) in 2 individuals with functionally solitary kidneys. METHODS: Under general anesthesia and in the prone position, 2 patients underwent electrovaporization of upper tract TCC through upper pole percutaneous access. Using either a rollerball (Case 1) or the VaporTrode (Case 2) electrode at 200 W pure cutting current, the tumors were completely vaporized. RESULTS: Average operating room time was 145 minutes. Hemostasis was excellent. No significant perioperative complications were noted. A nephrostogram at the end of the procedure revealed no extravasation in either case. There was no appreciable change in serum creatinine. Both patients received postoperative mitomycin (40 mg in 1000 cc normal saline over 20 hours) through the nephrostomy tube. One patient (Case 2) is completely free of disease via antegrade nephroscopy and biopsy at 2 weeks' follow-up. The other patient (Case 1) had two remaining focal areas of tumor via antegrade nephroscopy 3 weeks postoperatively; both lesions were treated with electrovaporization via a flexible electrode through the flexible cystoscope and the VaporTrode, respectively. CONCLUSIONS: Percutaneous electrovaporization of upper tract TCC appears to provide a simple, rapid, and effective endosurgical treatment in properly selected patients. Long-term follow-up will be needed to assess this new treatment modality definitively.

Aged↗
PubMed1995

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

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

Animals↗
PubMed1995

Comparison of newer laparoscopic port closure techniques in the porcine model.

Obtaining a precise fascial closure of larger laparoscopic port sites presents an ongoing challenge for even the most experienced laparoscopic surgeons. To this end, we evaluated five new methods for closing laparoscopic port sites and compared these with the standard technique of a hand-sutured repair using a 0 absorbable suture in the pig. The new devices studied were the Carter-Thomason Needle-Point Suture Passer (CTNSP), the eXit Disposable Puncture Closure (EDPC) device, the Maciol suture needle (MSN) set, the Endoclose suture carrier, and a nonpropreitary technique using a long 14-gauge Angiocatheter and a looped Prolene suture. Unlike the typical clinical situation, the fascia of the pig lies extremely close to the skin; hence, the sutured closure could be routinely performed most quickly of all. Among the newer techniques, the CTNSP provided the quickest closure. The Endoclose, MSN, and 14-gauge Angiocatheter techniques required the use of an auxiliary grasper, which appeared to slow the closure. Only the EDPC provided an airtight closure in 100% of cases. Of the new techniques, the 14-gauge Angiocatheter technique was the least expensive ($3). The efficacy of these techniques in the clinical realm needs to be assessed by a randomized trial.

Animals↗
PubMed1995

Laparoscopic retropubic auto-augmentation of the bladder.

The small capacity or contracted bladder is a difficult management problem. The goal of bladder augmentation is to create a storage structure with an adequate capacity and low pressure. Bladder auto-augmentation creates a large bladder diverticulum by partially excising the detrusor muscle. We report our initial experience with an extraperitoneal approach to laparoscopic auto-augmentation in a patient with a small contracted bladder. This is a technically feasible operation but longer clinical followup is necessary to determine its durability in the management of the small contracted bladder.

Adult↗
PubMed1995

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

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

Animals↗
PubMed1995

Epidermal growth factor precursor is present in a variety of human renal cyst fluids.

Progressive human renal cystic diseases are characterized by proliferation of the epithelial cells lining the cyst. The kidney synthesizes epidermal growth factor and its presence in renal cyst fluid might contribute to renal epithelial cell proliferation. We screened autosomal dominant polycystic kidney disease, acquired renal cystic disease, the von Hippel-Lindau syndrome, multilocular cystic nephroma, multicystic dysplastic kidney disease and simple cyst fluids for the presence of epidermal growth factor by radioreceptor assay, specific radioimmunoassay, immunoprecipitation and immunoblotting. Multiple epidermal growth factor immunoreactive species of approximately 180 kD. and lower molecular weights were present in almost all cyst fluids examined, suggesting endogenous synthesis and limited proteolysis of epidermal growth factor precursor protein in cyst fluid. Tamm-Horsfall protein was detected by enzyme-linked immunosorbent assay in most cysts (for example 55 of 59 autosomal dominant polycystic kidney disease samples). The majority of simple and autosomal dominant polycystic kidney disease renal cysts contained high sodium ion concentration, epidermal growth factor precursor protein and Tamm-Horsfall protein, characteristic of the early thick ascending limb. Rather than the mere presence of epidermal growth factor in renal cyst fluids, increased sensitivity to epidermal growth factor or other mitogens present in renal cyst fluid may be pathogenic in progressive renal cystic disease.

Epidermal Growth Factor↗
PubMed1995

Complications of laparoscopic nephrectomy in 185 patients: a multi-institutional review.

PURPOSE: We document the incidence of complications associated with laparoscopic nephrectomy in a multi-institutional study. MATERIALS AND METHODS: The study included the initial 185 patients undergoing laparoscopic nephrectomy at 5 centers in the United States between June 1990 and July 1993. RESULTS: A total of 30 patients (16%) had 34 complications. There was no mortality. Access-related complications included 2 cases of hernia formation at the trocar site, 1 abdominal wall hematoma and 1 trocar injury to a hydronephrotic kidney. Intraoperative complications included 5 cases of vascular injury, 1 splenic laceration and 1 pneumothorax. Postoperative complications involved the gastrointestinal tract in 6 cases, cardiovascular system in 6, genitourinary tract in 4, respiratory system in 4 and musculoskeletal system in 2. Miscellaneous complications occurred in 3 patients. Open surgical intervention was required electively in 8 patients and on an emergency basis in 2. The incidence of complications decreased with experience: 71% occurred during the initial 20 cases at each institution. CONCLUSIONS: In our early experience the complication rate for laparoscopic nephrectomy was 12% in patients with benign renal disease and 34% in those with renal cancer. Based on this collective experience, recommendations for prevention, recognition and treatment of complications are made.

Adult↗
PubMed1995

Laparoscopic assisted continent urinary diversion in the pig.

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

Animals↗
PubMed1995

Laparoscopic pneumodissection: a unique means of tissue dissection.

PURPOSE: To study the acute and chronic tissue effects of using high pressure CO2 to dissect tissues during laparoscopic procedures. MATERIALS AND METHODS: A 5-mm. laparoscopic pneumodissector, capable of delivering brief bursts of high pressure CO2 (20 to 100 psi), was discharged on a variety of porcine tissues including the renal hilum. Acute and chronic histological sections, intraoperative blood gases and perioperative renal scans were obtained. RESULTS: The only tissue with significant acute damage was the spleen. Acute changes in other tissues were minimal; long-term studies revealed no discernible damage to these same tissues. Intraoperative blood gases revealed no significant changes in the serum pCO2 or pH. Likewise, there was no renal damage discernible by renal scans. CONCLUSIONS: Pneumodissection at 50 psi is a safe method for dissecting the porcine kidney and the vessels of the renal hilum. Clinical studies are pending.

Animals↗