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R V Clayman

Publications and source records attributed to R V Clayman.

At least 127 records · Page 7Linked to original sources
PubMed1996

Endourologic management of stone-bearing excluded calices: contrasting case reports.

Calculi in a noncommunicating or excluded calix may be associated with infection, pain, and focal renal damage. Some authors have recommended removal of these calculi and reestablishment of the pelvicaliceal communication, either by dilation of the infundibulum or creation of a neoinfundibulum, in order to prevent recurrent stone formation and infection. Herein, we report two patients with stones in a completely excluded calix, one after repeated courses of shockwave lithotripsy for a staghorn calculus and the other after recurrent pyelonephritis. The combined approach is especially helpful if the examiner is in doubt about the anatomy (true calix v caliceal diverticulum) or if a natural infundibulum cannot be identified by antegrade endoscopy.

Adult↗
PubMed1996

Laparoscopic bladder seromyotomy: laboratory experience.

Twelve female microminipigs with normal bladder capacity underwent laparoscopic bladder seromyotomy. Three other female microminipigs were added to the study as controls. Urodynamic studies and cystograms were performed preoperatively and at 2 and 4 months after a laparoscopic bladder seromyotomy. Histologic studies of the treated bladders were performed when the animals were euthanized at 4 months. The operation was completed in all 12 test animals. There was no significant difference in bladder capacity or leak-point pressure between the 12 seromyotomy and the 3 control bladders at any time point. Histologically, over the seromyotomy site, the urothelium remained intact; however, the muscularis was attenuated, and a thin layer of fibrotic tissue replaced the normal serosal covering of the bladder. Laparoscopic bladder seromyotomy can be performed reliably in the porcine animal model. Not surprisingly, no significant changes in bladder capacity or bladder compliance were seen in our study of normal bladders. An animal model of a neuropathic contracted bladder is needed to assess more accurately the physiological impact of laparoscopic seromyotomy.

Animals↗
PubMed1996

Comparison of acucise endopyelotomy and endoballoon rupture for management of secondary proximal ureteral stricture in the porcine model.

At this point in time, endopyelotomy is first-line therapy for both primary and secondary adult ureteropelvic junction obstruction (UPJO) in many medical centers. However, the potential, albeit small, for significant bleeding with any endoincision of the UPJ has sparked interest in the simple, less morbid technique of endoballoon rupture. To date, no comparative data are available on the effectiveness of these two techniques. Thirty female minipigs were randomized to cutting balloon (Acucise) endopyelotomy (AEP) (N = 13), endoballoon rupture (EBR) (N = 13), or a control arm (N = 4). Following baseline retrograde pyelogram (RPG) and diuretic renogram (DRG), a secondary proximal ureteral stricture was created by laparoscopic ligation of the UPJ. After 8 weeks, AEP or EBR was performed in each of the study pigs. In 16 pigs (8 AEP, 8 EBR), a 7F 22-cm ureteral stent was placed (chronic arm). After 6 weeks, the stent was removed, and a second RPG and DRG were performed. Three months post-treatment, after RPG and DRG, the renal units were harvested, and histologic sections of the affected UPJ, contralateral normal ureter, and ipsilateral kidney were examined. Ten pigs (5 AEP, 5 EBR) underwent harvest immediately after treatment (acute arm). The four control animals remained untreated. At 8 weeks, all minipigs had obstructive findings on RPG and DRG. All UPJs could be treated but one, which had an impassable stricture; there were no perioperative complications. In the acute arm, all UPJs were patent. All five AEP ureters had evidence of an uneven cut and cautery effect. Of the EBR ureters, two had smooth tears and three had ragged tears, and none had evidence of cautery effect. In the chronic arm, 3 months after either AEP or EBR, all minipigs had a patent UPJ, yet only 5 of 16 had an improved 1 1/2 by DRG. Histologic sections of the affected UPJs from 20 minipigs in the chronic arm (8 AEP, 8 EBR, 4 controls) were indistinguishable among the three groups; each revealed significant periureteral fibrosis and chronic inflammation with a mainly unremarkable muscular layer. However, histologic sections of 25 treated kidneys, including both acute and chronic animals (13 AEP, 12 EBR), revealed endstage renal disease (N = 10), chronic inflammatory changes (N = 7), or normal tissue (N = 8). Again, there was no trend favoring either AEP and EBR. In summary, in this laboratory study, we could detect no difference in outcome between an incisional endopyelotomy and an endoballoon rupture for treating secondary UPJO.

Animals↗
PubMed1996

Comparison of three-dimensional and two-dimensional laparoscopic video systems.

The limitations of two-dimensional (2D) video may be overcome by the recent introduction of the three-dimensional (3D) laparoscope and video system. Twenty-two urologic and gynecologic surgeons experienced in laparoscopy were evaluated during a live porcine laboratory session in an advanced course designed to teach laparoscopic retroperitioneal nephrectomy and bladder neck suspension. The surgeons performed dissection of the kidney, securing of the renal vessels, laparoscopic suturing and intracorporeal knot-tying at the bladder neck, and suture clipping of an intracorporeally placed suture at the bladder neck using 2D and 3D equipment. The time needed to complete each technique was recorded and compared using nonparametric analysis. The participants' subjective evaluation of the 3D system was also analyzed. Three-dimensional video did not significantly improve the surgeons' ability to perform laparoscopic dissection of the kidney, securing the renal vessels, or laparoscopic suturing and knot-tying. Surgeons felt that the 3D system did not improve vision or perceived surgical performance sufficiently to justify an expense greater than that of the 2D systems now available. Compared with the standard 2D camera system, the currently available 3D video system does not hasten the laparoscopic dissection of tissues or the performance of advanced technical maneuvers such as laparoscopic suturing and knot-tying by experienced laparoscopists.

Adult↗
PubMed1996

Laparoscopic nephrectomy for benign disease: comparison of the transperitoneal and retroperitoneal approaches.

We report our experience with the transperitoneal (TP) and retroperitoneal (RP) approaches for performing laparoscopic nephrectomy for benign disease. Thirty-three patients with benign renal disease underwent laparoscopic nephrectomy, 23 by the TP and 10 by the RP approach. The average age of the patient, ASA score, and specimen weight were similar for the two groups. The average operating time for the TP approach was 5.6 hours v 5 hours for the RP approach. The average hospital stay was 2.8 and 3 days for TP and RP groups, respectively. The use of postoperative analgesics was similar in the two groups (37 mg of morphine sulfate equivalent v 39 mg of morphine sulfate equivalent for the TP and RP groups, respectively). However, the RP group required less time to resume normal oral intake than the TP group (0.3 v 0.6 days). When assessed according to specimen weight of 100 or less, there was a significant reduction in the postoperative analgesia requirements for the RP group of patients (11 mg of morphine sulfate equivalent v 28 mg of morphine sulfate equivalent for the TP group). In this subgroup of patients, the resumption of oral intake also occurred more quickly in the RP than the TP group (0.4 v 0.5 days). The hospital stay and total convalescence time were similar for the two groups. Four complications occurred in the 33 patients: 2 patients (1 TP and 1 RP), required conversion to open surgery, 1 asthenic patient developed a vastus lateralis bruise undergoing a TP approach, and a brachial nerve palsy occurred in a morbidly obese patient who failed a TP approach. The RP approach to laparoscopic nephrectomy reduces the time to resuming normal oral intake for patients postoperatively and, in those patients with a small specimen, may significantly reduce their postoperative analgesia requirements. However, the RP approach for laparoscopic nephrectomy for benign disease does not significantly improve the length of hospital stay or the patient's ultimate postoperative return to normal activity in comparison to the TP approach. There does appear to be a trend toward a shorter operative time for the RP approach. The RP laparoscopic approach is our method of choice for patients with benign renal disease.

Adolescent↗
PubMed1996

Comparative ureteral microanatomy.

Several animals have been used as models for experimental upper urinary tract surgery. Although minipigs have recently gained favor because their upper urinary tract is grossly similar to that of humans, the ureteral microanatomic features of the two species have not been compared. We evaluated the histologic features of human and animal ureters in order to provide addition information regarding experimental models for upper urinary tract surgery. Cross-sections of upper, middle, and lower ureteral segments from human autopsy specimens and animals (farm pig, minipig, dog, sheep, rabbit, and rat) were evaluated after preparation with Masson's trichrome stain. Morphology, computer-assisted morphometry, linear micrometry, and point-count estimation of smooth muscle/connective tissue ratios were assessed. The epithelium was remarkably consistent across all species, both morphologically and in terms of absolute size. The lamina propria was highly vascularized in all species, but the compactness varied with the overall ureteral dimensions. In the muscularis, the relative size and the percentage composed of smooth muscle differed widely among species, as did the ratio of muscularis to lamina propria cross-sectional surface area. Among the species evaluated, the sheep, farm pig, and minipig ureters were the best histologic approximations of the human ureter. Given the difficulties with manipulation of the small sheep ureter, the minipig and farm pig models appear to be optimal for experimental research on upper urinary tract surgery by an endourologic approach.

Aged↗
PubMed1996

Imaging for ureteropelvic junction obstruction in adults.

The three goals of imaging for ureteropelvic junction (UPJ) obstruction are to determine the presence and degree of renal obstruction, to assess renal function, and to determine the cause of the problem. The diagnostic techniques are intravenous urography, which is unreliable; ultrasonography, with the addition of pulsed Doppler technology; diuretic scintigraphy; and pressure-flow studies (Whitaker test), which is the only direct clinical test of renal outflow resistance. Voiding cystography, retrograde ureteropyelography, and CT have utility in some patients. In determining the cause of obstruction, the patient often is evaluated for crossing vessels using angiography, endoluminal ultrasonography, or spiral CT. It is not possible to formulate a single algorithm for radiographic evaluation of suspected UPJ obstruction, but in the average adult patient, urography and diuretic scintigraphy are sufficient.

Adult↗
PubMed1996

Helical (spiral) CT angiography for identification of crossing vessels at the ureteropelvic junction.

OBJECTIVE: The purpose of this study was to determine the feasibility of imaging crossing vessels at the ureteropelvic junction (UPJ) with helical (spiral) CT angiography for planning surgical repair of symptomatic UPJ obstruction. SUBJECTS AND METHODS: Twenty-four consecutive patients with symptomatic UPJ obstruction were imaged with dual-phase, contrast-enhanced helical CT (collimation, 3 mm; pitch, 1.3-1.7; reconstruction interval, 2 mm; early phase, 20-42 sec; and delayed phase, 90-112 sec after initiation of IV contract material injection [125 ml of ioversol containing 320 mg of iodine per ml, delivered at 4-5 ml/sec]). All imaging data were viewed interactively on an imaging workstation. Prospective on-line interpretations were correlated with subsequent surgical and clinical findings at laparoscopy (n=3), open surgical repair (n=2), or ureteronephroscopic endopyelotomy (n=11). Vessels at the UPJ that were 2 mm or more in diameter were believed to be significant. Review of the transaxial images was performed to determine qualitatively the relative usefulness of the early versus the delayed phases for distinguishing arteries from veins. Multiplanar reformations also were retrospectively reviewed and compared with direct pyelograms to determine the accuracy with which the location of the UPJ and the proximal ureteral course were depicted with helical CT. RESULTS: Eleven of 24 (46%) patients collectively had 11 anterior and three posterior vessels (> or = 2 mm in diameter) crossing the UPJ on helical CT. Distinction between arteries and veins was significantly better on early-phase than on delayed-phase images (p=.01). Visualization of the UPJ and the proximal ureteral course was good or excellent for 18 (78%) of 23 patients for whom pyelograms were available, regardless of the presence of a ureteral stent (p>.05). Laparoscopy and open surgery findings were in agreement with helical CT angiograms for five of five patients. Uncomplicated endopyelotomy was performed for 11 patients in whom no significant vessels were seen posterior or posterolateral to the UPJ. CONCLUSION: Helical CT angiography can depict vessels crossing the UPJ and is valuable in planning surgical management.

Adolescent↗
PubMed1996

Frontiers in laparoscopy: economic issues and future perspectives.

A little over 5 years ago, laparoscopy was introduced into the field of urology via the pioneering work of William Schuessler, and later Howard Winfield, in the realm of laparoscopic pelvic lymph node dissection. Since then, much has happened in this area and in reconstructive laparoscopic surgery. For urologists pursuing laparoscopic training, lymph node dissection remains the primary setting in which to learn the technique. In the first part of this roundtable, our panelists discussed applications of laparoscopy. Here, they examine economic issues related to the technology and give us a glimpse of what the future holds.

Costs and Cost Analysis↗
PubMed1996

The effect of prolonged pneumoperitoneum on renal function in an animal model.

BACKGROUND: Prolonged, increased intra-abdominal pressure (IAP) during laparoscopic surgery has been associated with oliguria and anuria. STUDY DESIGN: The objective of this study was to evaluate the effects of various levels of IAP on renal function. Ten groups of three adult female farm pigs were given a general anesthetic, followed by establishment of an IAP of 0, 5, 10, 15, or 20 mm Hg with CO2, 20 mm Hg with argon gas, abdominal wall lift device, renal vein occlusion (RVO), 15 mm Hg with CO2 plus dopamine administration at 2 microgram/kg/minute, or 20 mm Hg retroperitoneal CO2 insufflation. The following studies were recorded: baseline central venous pressure (CVP), pulmonary wedge pressure (PWP), cardiac output (CO), renal vein flow (RVF), renal artery pressure (RAP), selective urine output (UO), urinary osmolarity, and creatinine clearance; the parameters were repeated every 30 minutes for the four hours of the IAP study and two hours after release of the IAP. RESULTS: The results were analyzed within two main IAP groups: less than 15 mm Hg and greater than or equal to 15 mm Hg. There was no clinically significant variation in the CVP, PWP, and RAP. The CO decreased slightly and this was more significant in the greater than or equal to 15 mm Hg group. The RVF and UO decreased concomitantly and significantly in the greater than or equal to 15 mm Hg group. Even after two hours of desufflation, the RVF did not return to baseline, although the UO improved. Creatinine clearance decreased significantly in the greater than or equal to 15 mm Hg group. The RVO group exhibited similar changes in the study parameters as those seen in the greater than or equal to 15 mm Hg group, although the RVF did not improve on release of the renal vein in the RVO group. Changes were the same with an argon or CO2 IAP of 20 mm Hg. The abdominal wall lift device had an associated decrease in RVF at 15 KG force but no alteration in UO. Retroperitoneal insufflation resulted in the same decrease in RVF and UO as seen with the same IAP. Dopamine did not afford a protective effect on UO during an IAP of 15 mm Hg. CONCLUSIONS: The decreased UO during prolonged IAP greater than or equal to 15 mm Hg in the animal model is associated with a corresponding decrease in RVF, but does not appear to be associated with any permanent renal derangement nor any transient histologic changes.

Animals↗
PubMed1996

Laparoscopic radical nephrectomy for renal tumor: the Washington University experience.

PURPOSE: We report our experience with laparoscopic radical nephrectomy in 17 consecutive patients with renal tumors. MATERIALS AND METHODS: The clinical data on 17 consecutive patients undergoing laparoscopic radical nephrectomy were reviewed. Of the patients 12 with stage pT1 or pT2 renal cell carcinoma 7 cm. in diameter or smaller undergoing laparoscopic radical nephrectomy were compared to 12 undergoing open radical nephrectomy for stage pT1 or pT2 renal cell carcinoma 6 cm. in diameter or smaller. RESULTS: Among the 17 patients undergoing laparoscopic radical nephrectomy average operative time was 6.9 hours (range 4.5 to 9) and average estimated blood loss was 105 cc (range 50 to 600). Average weight of the surgical specimen was 402 gm. (range 190 to 1,100). In 12 of 16 patients in whom laparoscopic radical nephrectomy was completed the specimen was removed intact. The patients required an average of 24 mg. morphine sulfate equivalent (range 2 to 220) for postoperative pain. Average hospital stay was 4.5 days (range 3 to 11) and average interval to resume normal activities was 3.5 weeks (range 2 to 4). The 12 patients in the open and laparoscopic radical nephrectomy groups were similar with respect to age, American Society of Anesthesiologists score and interval surgery. Laparoscopic radical nephrectomy required significantly more operative time than open radical nephrectomy (6.9 versus 2.2 hours, respectively). However, the laparoscopic radical nephrectomy group compared to the open radical nephrectomy group had significantly less postoperative pain (24 versus 40 mg. morphine sulfate equivalent required for postoperative analgesia), shorter interval to resuming oral intake (1 versus 3 days), more rapid discharge from the hospital (4.5 versus 8.4 days) and more rapid return to normal activities (3.5 versus 5.1 weeks). The laparoscopic nephrectomy group also fully recovered more rapidly than the open surgical group (5.8 versus 39 weeks). To date, during a 4-year period there was no retroperitoneal recurrence or seeding of port site. CONCLUSIONS: Laparoscopic radical nephrectomy is a lengthy and demanding procedure. However, it affords patients with renal cell carcinoma a markedly improved postoperative course while accomplishing the necessary surgical goals.

Adult↗
PubMed1996

The unintubated ureterotomy endourologically revisited.

PURPOSE: The duration of stenting after endoureterotomy is a controversial issue. An even more basic question, however, is whether stent placement is needed at all. We performed a porcine study to address this question. METHODS: A unilateral midureteral stricture was created in 20 minipigs. Six weeks later, 15 pigs underwent endoureterotomy. In 10 animals, a 7F ureteral stent was placed for 1 week. Five pigs remained unstented. Three months later, all 20 ureters were studied radiographically and were harvested. RESULTS: Three of 5 control animals and 2 of 10 stented animals has strictures. In the unstented study group, all 5 animals had a nonobstructing dilation at the site of endoureterotomy. This was corroborated by a normal furosemide washout renal scan in all 3 animals so tested. CONCLUSIONS: The result of unstented endoureterotomy in the porcine model suggests that, after endoureterotomy of secondary midureteral strictures, stenting may be unnecessary.

Animals↗
PubMed1996

Ureteral cell cultures. I. Characterization and cellular interactions.

PURPOSE: To further understand the biology of ureteral cells, we studied the growth characteristics and in vitro cellular interactions of human ureteral uroepithelial cells, smooth muscle cells and myofibroblasts. MATERIALS AND METHODS: The proliferation, morphology and immunohistochemical characteristics of human ureteral cells grown in vitro were evaluated under varying conditions. RESULTS: The growth and morphology of ureteral cells were dependent upon media characteristics, especially the calcium concentration and presence of epidermal growth factor and bovine pituitary extract. Cells demonstrated specific stimulatory interactions via both soluble and insoluble factors. Most important, uroepithelial cells and smooth muscle cells displayed reciprocal enhancement of growth. CONCLUSIONS: The favorable interactions between ureteral cell types in vitro have implications for future work involving these cells.

Cell Communication↗
PubMed1996

Comparative clinical study of port-closure techniques following laparoscopic surgery.

BACKGROUND: Recently, a number of laparoscopic port-closure techniques have been reported to avoid the complications associated with the port closure after laparoscopic surgery. To evaluate these port-closure techniques, we compared seven new laparoscopic port-closure techniques with the standard technique of a hand-sutured closure. STUDY DESIGN: In a prospective, randomized study, 95, 12-mm port sites in 32 patients undergoing transperitoneal laparoscopic procedures were randomized to one of eight different port-site closure techniques. The port-closure techniques included: the Carter-Thomason Needle-Point Suture Passer, Maciol suture needle set, eXit Disposable Puncture Closure device, Endoclose suture carrier, Tahoe Surgical Instruments Ligature device, a long 14-gauge angiocatheter with looped polypropylene suture, Lowsley retractor with hand-sutured closure, and the standard technique of hand-sutured closure. We evaluated the time, the security, and the auxiliary instrumentation required for each closure. RESULTS: Of the port-closure techniques, the Carter-Thomason device was faster overall, resulted in fewer port-closure-related complications and provided a leak proof closure. CONCLUSIONS: The Carter-Thomason device is our preferred method for the closure of port sites after laparoscopic surgery.

Female↗
PubMed1996

Intracorporeal electrohydraulic lithotripsy of ureteral and renal calculi using small caliber (1.9F) electrohydraulic lithotripsy probes.

PURPOSE: The development of 1.9F or smaller electrohydraulic lithotripsy probes has facilitated the use of this form of lithotripsy via miniature rigid and flexible ureteroscopes. We report our experience with ureteroscopic intracorporeal lithotripsy using 1.9F electrohydraulic lithotripsy probes. MATERIALS AND METHODS: A total of 45 patients (32 ureteral and 57 renal calculi) underwent retrograde rigid (microscopic to 6F short) or flexible (7.5 and 9.4F) ureteroscopy with electrohydraulic lithotripsy using 1.9F electrohydraulic lithotripsy probes. In 17 patients (38%) there were 37 lower pole caliceal calculi (41%). Stone size ranged from 3 to 30 mm. (mean 8.5). RESULTS: Electrohydraulic lithotripsy resulted in successful fragmentation (that is 2 mm. or smaller fragments) in 98% of patients overall. It was successful after failure of HM-3 extracorporeal shock wave lithotripsy in 10 patients and after failed lithotripsy with the 140 mJ. tunable dye laser in 7. Electrohydraulic lithotripsy resulted in successful fragmentation of 94% of lower pole caliceal stones. No intraoperative complications and no significant ureteral or renal mucosal damage were noted. Fever developed postoperatively in 2 patients (4.4%) with negative urine cultures. Postoperatively an indwelling stent was placed for 2 weeks or less in 71% of patients and no stents were placed due to preoperative stenting in 29%. Average hospital stay was 0.8 days (range 0 to 4). Followup imaging in 38 patients (84%) at a mean of 8.7 months (range 2 to 28) revealed stone-free rates of 92% overall and 87% in patients with lower pole renal calculi. No patient had a ureteral or infundibular stricture postoperatively. CONCLUSIONS: The development of 1.9F or smaller electrohydraulic lithotripsy probes provides the urologist with a safe, highly effective and inexpensive method for performing intracorporeal lithotripsy throughout the entire upper urinary tract via rigid or flexible ureteroscopes. Furthermore, for the ureteroscopic treatment of lower pole renal calculi electrohydraulic lithotripsy is the only form of intracorporeal lithotripsy sufficiently malleable to allow routine access.

Adolescent↗
PubMed1995

Laparoscopic nephropexy: Washington University experience.

PURPOSE: We evaluated the efficacy of laparoscopic nephropexy for symptomatic nephroptosis. MATERIALS AND METHODS: We performed laparoscopic right nephropexy in 6 patients who presented with symptomatic nephroptosis documented by radiographic studies and/or renal scans. In the first patient Gerota's fascia was secured to the peritoneal reflection of the line of Toldt using tacking clips. In the subsequent 5 patients the lateral border of the kidney was sutured to the overlying fascia of the quadratus lumborum muscle using an intracorporeal suturing technique. Additionally, the superior edge of the incised infrahepatic triangular ligament was sutured to the anterior mid portion of the renal capsule, thereby creating a vertical and horizontal means of fixation. RESULTS: Laparoscopic right nephropexy was successful in all 6 patients. Average operative time was 4 hours. All patients resumed oral intake during postoperative day 1. Average parenteral analgesia requirement postoperatively was 42.7 mg. morphine. Hospital stay averaged 2.5 days and patients returned to usual activities an average of 2.5 weeks postoperatively. Postoperative imaging studies confirmed a decrease in or resolution of nephroptosis in all patients. All patients remained asymptomatic for an average of 11 months (range 2 to 30). CONCLUSIONS: Laparoscopic nephropexy appears to be a feasible treatment option for patients with symptomatic, documented nephroptosis. The procedure can be accomplished safely and effectively with satisfactory anatomical and clinical results.

Adult↗