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Biomedical subjects

R V Clayman

Publications and source records attributed to R V Clayman.

At least 19 recordsLinked to original sources

Laparoscopic radical prostatectomy: review and assessment of an emerging technique.

BACKGROUND: Several recent reports have affirmed the feasibility of the laparoscopic approach for radical prostatectomy. In this review, we discuss the morbidities associated with this technique and compare outcomes and convalescence with standard open radical prostatectomy. METHODS: We reviewed all currently published data on laparoscopic radical prostatectomy and our series of 45 robotic-assisted radical prostatectomies and compared them to several landmark series of open retropubic and perineal radical prostatectomies. RESULTS: Although the initial series reported long operating times, these times have been significantly reduced in more recent series. Data on blood loss, convalescence, impotence, and incontinence rates have also been promising. CONCLUSIONS: Although follow-up has been short thus far, laparoscopic radical prostatectomy has been shown to be similar to open radical prostatectomy in several areas.

Humans↗

Dual-organ ablative surgery using a hand-assisted laparoscopic technique. A report of four cases.

In clinical situations where more than one procedure is required, a properly positioned hand-assist device can be used to obviate the need for two large incisions. We present four cases of hand-assisted laparoscopic nephrectomy combined with a simultaneous second organ extraction. Each of the four primary procedures, as well as one of the four secondary procedures, was performed using a hand-assisted laparoscopic technique. In two cases, the secondary procedure was performed with an open surgical technique through the hand-assist incision. For the remaining secondary procedure, we used a laparoscopically assisted technique.

Aged↗

Should laparoscopy be the standard approach used for radical nephrectomy?

Since its inception in June 1990, laparoscopic radical/total nephrectomy for renal tumor has been successfully applied worldwide to hundreds of patients. Recent 5-year follow-up data have shown this procedure to produce cancer control identical to that of open radical/total nephrectomy. Although in most centers the cost of the procedure remains higher than open surgery, the patient benefits of decreased pain, reduced hospitalization, less blood loss, and more rapid convalescence appear to be universal. At this time, we believe that laparoscopic radical/total nephrectomy for the treatment of renal tumors should become the new standard of care.

Humans↗

Lower pole I: a prospective randomized trial of extracorporeal shock wave lithotripsy and percutaneous nephrostolithotomy for lower pole nephrolithiasis-initial results.

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

Humans↗

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

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

Animals↗

Laparoscopic radical/total nephrectomy: a decade of progress.

The first laparoscopic radical/total nephrectomy for a renal tumor was performed in June 1990. Since that time, the procedure has evolved as numerous surgeons have contributed novel strategies and technical advances. The state of the art is reviewed, including transperitoneal laparoscopic and hand-assisted techniques, as well as the retroperitoneal approach. Operative and postoperative data are reviewed with the goal of determining four factors: the efficacy, efficiency, morbidity, and cost of the procedure. Within the limits of available follow-up for this novel procedure, it appears to be as effective as open surgery in rendering the patient tumor free. Although it clearly is a less painful and less disabling procedure than open surgery, our understanding of the efficiency of the laparoscopic procedure remains in flux. The operative times for laparoscopic radical/total nephrectomy are approaching those of traditional open radical nephrectomy, although intraoperative costs remain higher and thus must be balanced against decreased hospitalization and convalescence.

Humans↗

Flexible ureteroscopic lithotripsy: first-line therapy for proximal ureteral and renal calculi in the morbidly obese and superobese patient.

BACKGROUND AND PURPOSE: The surgical treatment of kidney and proximal ureteral stones in morbidly obese patients (>14 kg/m2) remains difficult because shockwave lithotripsy is precluded by weight limitations and percutaneous nephrolithotomy is associated with difficult access and a high (9%) rate of transfusion. We review our experience with retrograde ureteroscopic lithotripsy in morbidly obese patients with renal and proximal ureteral stones. PATIENTS AND METHODS: Between December 1992 and April 2000, five women and three men with a mean age of 46.5 years (range 33-68 years) and a mean body mass index of 54 (range 45-65.2) underwent 10 independent ureteroscopic procedures for urolithiasis. The average stone size was 11.1 mm (range 5-25 mm). Lithotripsy was performed with the holmium laser in eight patients (60%) the electrohydraulic lithotripter in four (30%), and the tunable-dye laser in the remaining patient. Stone-free status was defined as no stones visible on a plain film with nephrotomograms or CT scan at 3 months. RESULTS: The mean operation time was 101 minutes (range 45-160 minutes), and 60% of the procedures were done on an outpatient basis. After the initial procedure, the stone-free rate was 70%. Two patients had fragments <4 mm, and no further therapy was undertaken. There was one complication: transient renal insufficiency (serum creatinine concentration 3.7 mg/dL) secondary to aminoglycoside toxicity. No transfusions were needed. CONCLUSION: In the morbidly obese patient with symptomatic stones <1.5 cm, ureteroscopic lithotripsy is safe, successful, and efficient.

Adult↗

Laparoscopic management of retrovesical cystic disease: Washington University experience and review of the literature.

BACKGROUND AND PURPOSE: Recently, the laparoscopic approach to the management of seminal vesicle cysts has been described. This report outlines the Washington University experience and reviews the present literature to evaluate the results of the laparoscopic approach to the excision of retrovesical cysts of seminal vesicle and Müllerian origin. PATIENTS AND METHODS: The hospital and office records of three patients undergoing laparoscopic excision of seminal vesicle and Müllerian duct cyst disease between April 1993 and March 1999 were reviewed for the operative time, the estimated blood loss, total hospital stay, total analgesia required postoperatively, the time to resumption of oral intake, and the postoperative recovery. A literature search revealed two additional reports of laparoscopic management of cystic disease of the seminal vesicle, comprising only one and two patients. An additional review of the literature was performed to compare the laparoscopic procedure with the transvesical, transurethral, open transvesical, and open retrovesical approach for the management of the disease. RESULTS: For the three patients at Washington University, the operative time averaged 4 hours (range 1.8-6.1 hours), and the mean estimated blood loss was 150 mL (range 50-200 nL). The patients required a mean of 43 mg of morphine sulfate for postoperative pain control, had a mean hospital stay of 2.6 days, and resumed oral intake 5.8 hours postoperatively. In combination with the three other cases reported in the literature, the average operative time for laparoscopic retrovesical cyst excision was 2.9 hours, and the average hospital stay was 2.2 days. With an average follow-up of 17 months, all six patients had excellent resolution of their preoperative symptoms. There have been no major or minor complications or any need for further operative therapy. CONCLUSION: Laparoscopic excision of retrovesical cystic disease is an effective surgical procedure, associated with minimal postoperative morbidity, short hospitalization, and a rapid recovery for the patient.

Adult↗

Ureteral access for upper urinary tract disease: the access sheath.

Ureteral access with the flexible ureteroscope remains a challenge for the urologist. The routine use of a newly developed, site-specific ureteral access sheath facilitates entry into the ureter for fragmentation and basket extraction of ureteral and renal calculi. The step-by-step technique of ureteral access with the Access Sheath is described.

Equipment Design↗

Assessment of optimal balloon size for rupture of the ureteropelvic junction and mid-ureter in a porcine model.

PURPOSE: Balloon dilation potentially represents a safer and simpler technique for the treatment of ureteropelvic junction (UPJ) obstruction and ureteral strictures. Using a porcine model, we sought to establish the optimal balloon size for endoballoon rupture of the UPJ and ureter. MATERIALS AND METHODS: The efficacy of endoballoon rupture of the proximal and middle ureter with 24F, 30F, and 36F balloon catheters was compared in 19 female minipigs. At the proximal ureter, the effect of the rate of dilation also was evaluated for each balloon size. Extravasation of methylene blue-stained contrast material was assessed with retrograde pyelograms and direct laparoscopic vision. After acute sacrifice, the dilated segments were evaluated histologically with hematoxylin and eosin and Masson's trichrome staining. RESULTS: At the proximal ureter, free extravasation of contrast was observed in 61% of the rapid inflation and 72% of the slow inflation trials; contained extravasation was noted in 28% of the rapid inflation and 17% of the slow inflation trials. Except for two of the 24F slow inflation trials, all of the proximal ureteral trials produced at least one full-thickness tear into the periureteral fat. Grossly, the tears appeared linear with various lengths and no consistent orientation. Rapid inflation and increasing balloon size tended to produce a ureterotomy with less damage to the ureter surrounding the tear. At the mid-ureter, none of the balloon sizes consistently produced a transmural tear. CONCLUSIONS: Rapid dilation and use of a 36F balloon capable of maintaining a low profile after inflation may result in a cleaner proximal ureterotomy with less distortion of the untorn neighboring proximal ureter. Both 36F and 30F balloons consistently produced a full-thickness proximal ureterotomy in normal porcine tissue. For mid-ureteral strictures, balloon dilation to even 36F may fail to create a suitable ureterotomy. However, it must be noted that dysplastic or scarred tissue may respond differently to dilation than the more elastic normal porcine tissues used in this study.

Animals↗

Laparoscopic cyst marsupialization in patients with autosomal dominant polycystic kidney disease.

PURPOSE: Autosomal dominant polycystic kidney disease is characterized by progressively enlarging renal cysts associated with hypertension, renal failure, pain, hematuria and infection. We explored the role of laparoscopic cyst marsupialization for managing cyst related problems. MATERIALS AND METHODS: In 4 male and 11 female adults with autosomal dominant polycystic kidney disease who had preserved renal function laparoscopic cyst marsupialization was done for pain unilaterally and bilaterally in 9 and 6, respectively. An average of 204 cysts per kidney (range 11 to 635) were decorticated or drained. RESULTS: Average operative time was 5.5 hours. Patients were discharged from the hospital after an average of 3.2 days. At a mean followup of 2.2 years (range 0.5 to 5) pain was decreased an average of 62% (range 30% to 90%) in 11 cases (73%). One patient had no improvement and 1 had subsequent worsening of pain postoperatively. Two patients with initial improvement had pain recurrence 4 and 36 months postoperatively, respectively. Hypertension resolved in 1 patient (7%), improved in 20% and did not change in 40%. In 33% of the cases hypertension worsened, requiring additional antihypertensive medication. Renal function remained stable in 13 patients (87%), improved in 1 (6.5%) and worsened in 1 (6.5%). Overall patients who underwent a bilateral procedure had better long-term pain relief and more improvement in hypertension. CONCLUSIONS: Laparoscopic cyst marsupialization may effectively decrease cyst associated pain. In some cases hypertension may be improved. Renal function remained stable in all except 1 patient. At a mean followup of 2.2 years the benefits of aggressive laparoscopic cyst decortication appear to be relatively long lasting when bilateral decortication is indicated. The benefits of unilateral cyst decortication are less predictable and of shorter duration.

Adult↗

Laparoscopic bilateral hand assisted nephrectomy for autosomal dominant polycystic kidney disease: initial experience.

PURPOSE: The laparoscopic technique for bilateral nephrectomy in patients with autosomal dominant polycystic kidney disease is technically difficult. The procedure may be more acceptable if alterations to the technique made it safer and easier to perform. We describe our initial experience with, and the feasibility and potential benefits of hand assisted laparoscopic nephrectomy for approaching these large kidneys in patients with autosomal dominant polycystic kidney disease. MATERIALS AND METHODS: This approach was successfully applied in 3 patients with end stage renal disease due to autosomal dominant polycystic kidney disease. After obtaining transumbilical pneumoperitoneum ports were placed in the umbilicus (12 mm.), sub-xiphoid in the midline (12 mm.) and subcostal in the midclavicular line on each side (12 mm.). The table was tilted 40 degrees away from the planned side of initial nephrectomy with the patient in the half lateral position. A 7 cm. midline incision was made that incorporated the umbilical port and a commercially available hand assistance device was positioned. One surgeon hand was inserted into the abdomen to serve as a retractor/blunt dissector, while the other operated the electrosurgical instruments. The right hand was inserted for left nephrectomy and the left hand was inserted for right nephrectomy. The laparoscope was passed via the sub-xiphoid port and the instruments were placed through the ipsilateral subcostal laparoscopic port. Nephrectomy was completed and the specimen was removed through the hand port incision by draining the cysts as they were exposed to view via the midline incision. When dissection was difficult, an additional port was placed in the anterior axillary line at the umbilical level. Some cysts were ruptured or aspirated to decrease overall kidney size and make extraction possible via the 6 to 7 cm. midline incision. RESULTS: All procedures were successfully completed. Mean operative time for bilateral hand assisted laparoscopic nephrectomy was 5.5 hours (range 4.5 to 6.6). Estimated blood loss was 200 cc or less. Patients resumed oral intake on postoperative day 1. The mean amount of parenteral analgesics required postoperatively was decreased. Mean hospital stay was 4.3 days but it was 3 days when considering nephrectomy only. Patients returned to normal activity after an average of 2 weeks. There was sustained resolution of preoperative discomfort based on pain analog scales. At 1 month or less all patients recorded absent pain. They uniformly noticed improved preoperative pulmonary and gastrointestinal symptoms CONCLUSIONS: Hand assisted laparoscopic nephrectomy in patients with autosomal dominant polycystic kidney disease makes bilateral nephrectomy a reasonable option. The bilateral procedure may be performed as rapidly as laparoscopic only, unilateral nephrectomy in these cases. The advantages of the hand assisted approach include using tactile sensation to facilitate dissection, rapid blunt finger dissection, hand retraction and the application of immediate tamponade when needed. This procedure provides the benefits of minimal intraoperative blood loss, minimal postoperative pain, brief hospital stay and rapid convalescence in this group of patients at high risk.

Adult↗

Missed anterior crossing vessels during open retroperitoneal pyeloplasty: laparoscopic transperitoneal discovery and repair.

PURPOSE: Extrinsic ureteropelvic junction obstruction due to anterior crossing segmental renal vessels is present in more than 50% of patients in adulthood. In this situation the ureter must usually be dismembered and transposed anterior to the crossing vascular structures, where it is anastomosed to the renal pelvis. Via the open retroperitoneal approach there may be a limited view of the anterior surface of the ureteropelvic junction and, hence, anterior crossing vessels may possibly be missed. We describe 2 patients with ureteropelvic junction obstruction in whom anterior vessels were missed during open retroperitoneal repair. Laparoscopic transperitoneal secondary pyeloplasty with posterior displacement of the crossing renal vessel was performed in each case. MATERIALS AND METHODS: Two patients presented with symptomatic congenital ureteropelvic junction obstruction after failed endopyelotomy in 1 and failed open retroperitoneal procedures in both. Preoperatively spiral computerized tomography angiography with a ureteropelvic junction protocol revealed crossing vessels in the 2 cases. This finding was confirmed at transperitoneal laparoscopic pyeloplasty. The ureter and renal pelvis were transposed anterior to the crossing vessels and 2 rows of running sutures were placed to complete the anastomosis. RESULTS: The 2 laparoscopic procedures were completed successfully. The anterior crossing vessels were preserved in each case. Currently the patients are asymptomatic and furosemide washout renal scan was normal. CONCLUSIONS: Spiral CT angiography reliably delineates the renal vascular anatomy in patients with ureteropelvic junction obstruction. This study may be valuable before planned open retroperitoneal ureteropelvic junction obstruction repair. Laparoscopic pyeloplasty may successfully manage anterior crossing vessels associated with secondary ureteropelvic junction obstruction.

Adolescent↗

Prospective randomized trial comparing shock wave lithotripsy and ureteroscopy for management of distal ureteral calculi.

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

Adult↗

Use of new technology in endourology and laparoscopy by american urologists: internet and postal survey.

OBJECTIVES: To assess the use of new technology by American urologists. METHODS: Using the American Urological Association directory, surveys were sent via the U.S. postal service to 1000 randomly selected American urologists and 3065 urologists who had an Internet address listed in the directory. RESULTS: Responses were received from 601 urologists (415 postal, 186 Internet). Overall, 81% of survey respondents reported performing fewer or the same number of percutaneous procedures as compared with 3 to 4 years ago and 84% reported carrying out more or the same number of ureteroscopic procedures in the treatment of patients with stone disease. Open dismembered pyeloplasty (43%) and Acucise endopyelotomy (42%) were most frequently reported as the preferred treatment for adult patients with symptomatic ureteropelvic junction obstruction. Although 60% of respondents reported that they have taken a laparoscopy course, 67% currently do not perform any laparoscopy in their practice. In addition, only 7% of urologists stated that laparoscopy comprises more than 5% of their practice. When stratified by the number of years in practice, those in practice less than 10 years were more likely than those in practice 10 to 20 years and those in practice longer than 20 years to have performed an endopyelotomy (77%, 60%, and 48%, respectively, P <0.001) and to be currently performing laparoscopy (49%, 36%, and 18%, respectively, P <0.001). CONCLUSIONS: Compared with 3 to 4 years ago, American urologists are performing more ureteroscopy and fewer percutaneous stone procedures. Although most urologists have taken laparoscopy courses, this modality has not been widely incorporated into their practices at present.

Child↗

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.

Animals↗