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Ralph V Clayman

Publications and source records attributed to Ralph V Clayman.

At least 19 recordsLinked to original sources
PubMed2004

Ureteroscopes: flexible, rigid, and semirigid.

Since its introduction, the ureteroscope has undergone significant improvements. Using the currently available rigid, semirigid, and flexible ureteroscopes and working instruments, urologists can diagnose and treat lesions throughout the upper urinary tract. Over the past 25 years, the ureteroscope in combination with shock wave lithotripsy has transformed the diagnosis and treatment of more than 90% of upper urinary tract pathology from an open to an endourologic procedure. With endoscope manufacturers continually incorporating new technology into their ureteroscopes, future models will undoubtedly provide better optics, increased durability, and improved capabilities, resulting in greater success when urologists perform endoscopic forays into the upper urinary tract.

Equipment Design↗
PubMed2004

Needle-based ablation of renal parenchyma using microwave, cryoablation, impedance- and temperature-based monopolar and bipolar radiofrequency, and liquid and gel chemoablation: laboratory studies and review of the literature.

BACKGROUND AND PURPOSE: Small renal tumors are often serendipitously detected during the screening of patients for renal or other disease entities. Rather than perform a radical or partial nephrectomy for these diminutive lesions, several centers have begun to explore a variety of ablative energy sources that could be applied directly via a percutaneously placed needle-like probe. To evaluate the utility of such treatment for small renal tumors/masses, we compared the feasibility, regularity (consistency in size and shape), and reproducibility of necrosis produced in normal porcine kidneys by different modes of tissue ablation: microwaves, cold impedance-based and temperature-based radiofrequency (RF) energy (monopolar and bipolar), and chemical. Chemoablation was accomplished using ethanol gel, hypertonic saline gel, and acetic acid gel either alone or with simultaneous application of monopolar or bipolar RF energy. MATERIALS AND METHODS: A total of 107 renal lesions were created laparoscopically in 33 domestic pigs. Microwave thermoablation (N=12) was done using a Targis T3 (Urologix) 10F antenna. Cryoablation (N=16) was done using a single 1.5-mm probe or three 17F microprobes (17F SeedNet system; Galil Medical) (N=10 single probe and N=6 three probes); a double freeze cycle with a passive thaw was employed under ultrasound guidance. Dry RF lesions were created using custom-made 18-gauge single-needle monopolar probe with two or three exposed metal tips (GelTx) (N=12) or a single-needle bipolar probe (N=6) at 50 W of 510 kHz RF energy for 5 minutes. In addition, a multitine RF probe (RITA Medical Systems) was used in one set of studies (N=6). Both impedance- and temperature-based RF were evaluated. Chemoablation was performed with 95% ethanol (4 mL), 24% hypertonic saline (4 mL), and 50% acetic acid (4 mL) as single injections. In addition, chemoablation was tested with monopolar and bipolar RF (wet RF). Tissues were harvested 1 week after ablation for light microscopy. RESULTS: In 11 of the 15 ablation techniques, there was complete necrosis in all lesions; however, three ethanol gel lesions had skip areas, three hypertonic saline gel lesions showed no necrosis or injury, and one monopolar RF and one bipolar RF lesion showed skip areas. In contrast to impedance-based RF, heat-based RF (RITA) caused complete necrosis without skip areas. All cryolesions resulted in complete tissue necrosis, and cryotherapy was the only modality for which lesion size could be effectively monitored using ultrasound imaging. CONCLUSIONS: Cryoablation and thermotherapy produce well-delineated, completely necrotic renal lesions. The single-probe monopolar and bipolar RF produce limited areas of tissue necrosis; however, both are enhanced by using hypertonic saline, acetic acid, or ethanol gel. Hypertonic saline gel with RF consistently provided the largest lesions. Ethanol and hypertonic saline gels tested alone failed to produce consistent cellular necrosis at 1 week. In contrast, RITA using the Starburst XL probe produced consistent necrosis, while impedance-based RF left skip areas of viable tissue. Renal cryotherapy under ultrasound surveillance produced hypoechoic lesions, which could be reasonably monitored, while all other modalities yielded hyperechoic lesions the margins of which could not be properly monitored with ultrasound imaging.

Acetic Acid↗
PubMed2004

Hand-assisted laparoscopic nephrectomy in autosomal dominant polycystic kidney disease.

BACKGROUND: Among patients with renal insufficiency secondary to autosomal dominant polycystic kidney disease (ADPKD), the onset of refractory urinary infection, hypertension, pain, or hematuria often necessitates a nephrectomy. However, the huge size of these kidneys makes a standard laparoscopic approach difficult, and the increased fragility of these patients makes an open nephrectomy risky. A compromise position has been found in the realm of hand-assisted laparoscopic techniques, especially for patients in need of a bilateral nephrectomy. TECHNIQUE: Hand-assisted laparoscopic nephrectomy (HALN) is performed via a hand-assist device placed in the midline. A subxiphoid midline port and a midclavicular subcostal port are placed on the ipsilateral side. The right hand is inserted for left nephrectomy and the left hand for a right nephrectomy. The laparoscope is introduced into the subxiphoid port, and the surgeon's primary working instrument is passed via the midclavicular port. Occasionally, it is helpful to place a 5-mm subcostal port in the midaxillary line to aid in retracting the kidney. Once the kidney is devascularized, it is removed via the 7- to 8-cm hand-assist incision; drainage of cysts may be necessary during extraction to reduce the kidney size so that it can be withdrawn. If a bilateral approach is to be done, then after the first nephrectomy, the lateral 5-mm port is closed, and the table is rolled such that the contralateral side is elevated about 30 degrees to 45 degrees; a subcostal midclavicular 12-mm port is placed, and, if needed, a 5-mm port is inserted subcostally in the midaxillary line for renal retraction. RESULTS: Seven bilateral hand-assisted laparoscopic nephrectomy cases have been reported. In two reports, the mean operating times were 4.8 and 5.5 hours. The mean estimated blood loss was <350 mL. CONCLUSION: The hand-assisted laparoscopic approach makes both unilateral and bilateral nephrectomy feasible in ADPKD patients with acceptable morbidity.

Humans↗
PubMed2004

One-knot pyeloplasty.

Laparoscopic pyeloplasty represents one of the more advanced reconstructive procedures for the urologist. While early reports were replete with long operative times, there have been several changes that have added to the efficiency of the procedure. In our practice, we have found three changes to be of greatest value: (1) an upper-midline port placement; (2) use of a continuous suture for the anastomosis with a double-armed, knotted suture; and (3) antegrade stent placement.

Humans↗
PubMed2004

Intraoperative catheter management during laparoscopic excision of a giant bladder diverticulum.

BACKGROUND: Massive bladder diverticula present a technical challenge to the laparoscopic surgeon. We describe a laparoscopic approach to transperitoneal diverticulectomy, using a specific catheter arrangement to allow excellent control of the various portions of the procedure. METHODS: A 49-year-old male with longstanding frequency was diagnosed with a 1000 cc bladder diverticulum and bladder neck outlet obstruction. Laparoscopic transperitoneal diverticulectomy was performed using a triple catheter arrangement: endoscopic placement of a Councill catheter in the diverticulum, fluoroscopic positioning of an occlusion balloon catheter in the renal pelvis, and placement of a Cope loop suprapubic tube. Additionally, a transurethral incision of the prostate was performed. RESULTS: The procedure was completed laparoscopically using a four port transperitoneal approach. During the procedure, the diverticulum could be filled and emptied as needed; the catheter across the diverticular neck facilitated subsequent closure of the bladder wall defect. The diverticulum was completely excised. The remaining defect in the bladder was then closed in 2 layers. The patient was discharged on postoperative day 3. CONCLUSION: Careful planning and arrangement of catheters in the bladder, ureter, and diverticulum facilitates laparoscopic transperitoneal diverticulectomy of even a very large volume diverticulum.

Cystectomy↗
PubMed2004

Sealing percutaneous nephrolithotomy tracts with gelatin matrix hemostatic sealant: initial clinical use.

PURPOSE: Tubeless percutaneous nephrolithotomy (PCNL) has been performed at several centers with good success. However, these cases have been carefully selected with regard to short duration and smaller stone burden to prevent complications associated with the loss of access to the collecting system. We describe the use of gelatin matrix hemostatic sealant (FloSeal Baxter Medical, Fremont, California) as an adjunct to tubeless percutaneous nephrolithotomy to help preclude bleeding complications. MATERIALS AND METHODS: Two patients were treated with PCNL through a single nephrostomy tract. At the satisfactory conclusion of the cases the tract was occluded retrograde with an occlusion balloon catheter and gelatin matrix hemostatic sealant was injected down the nephrostomy tract. An indwelling stent and bladder catheter were placed following which all guidewires were removed and skin sutures were placed. RESULTS: The operative times were 75 and 180 minutes, respectively. Both patients had stable postoperative hemoglobin and no evidence of bleeding or obstruction on postoperative computerized tomography. CONCLUSIONS: Injection of gelatin matrix hemostatic sealant into the nephrostomy tract may be of value in preventing bleeding after PCNL. In this pilot experience it provided immediate and effective hemostasis.

Female↗
PubMed2004

Comprehensive evaluation of ureteral healing after electrosurgical endopyelotomy in a porcine model: original report and review of the literature.

PURPOSE: Endopyelotomy (EP) has yet to equal the success achieved with open dismembered pyeloplasty. To understand better the ureteral response to EP we performed a timed histopathological evaluation of the porcine ureter after Acucise (Applied Medical, Rancho Santa Margarita, California) EP. MATERIALS AND METHODS: In 28 domestic pigs bilateral Acucise EPs were performed and bilateral 7Fr stents were placed. The kidneys, ureters and bladder were harvested after EP at 0, 1, 2, 3, 6, 12 and 18 hours, 1, 3 and 5 days, and 1, 2, 4 and 8 weeks. The stents were removed after 4 weeks. The healing area of the ureter was sectioned. Half was fixed in formalin 10%, stained and evaluated by light microscopy. The other half was frozen and reverse transcriptase-polymerase chain reaction was performed to measure steady state levels of epidermal growth factor, transforming growth factor (TGF)-alpha, TGF-beta 1, TGF-beta 2, TGF-beta 3, keratinocyte growth factor, vascular endothelial growth factor, insulin-like growth factor, platelet derived growth factor, collagen type 1, integrin and fibronectin transcript expression. Immunohistochemistry for actin, desmin and myosin expression was completed. The same studies were applied to the mid portion of the unoperated ureter. RESULTS: Initial sealing of the ureterotomy defect was by blood clot and periureteral fat. Complete healing of the mucosa was observed at 2 weeks in animals without an associated urinoma. However, in no case did the muscle layer bridge the whole circumference of the ureter despite followup out to 8 weeks. In the operated ureter elevated expression of keratinocyte growth factor, vascular endothelial growth factor, TGF-alpha, TGF-beta 1, TGF-beta 3 and integrin was detected 2 hours after the operation and sustained for 7 to 14 days after the procedure. Immunohistochemistry revealed that most presumed myocytes seen in the defect were actually myofibroblasts. Persistent urinoma formation beyond the first few days appeared to slow the healing process. CONCLUSIONS: Urothelium regenerated rapidly over an iatrogenic ureteral defect despite the absence of a lamina propria. Muscle cell coverage failed to occur completely at 8 weeks. In the initial 8 weeks of the healing process myofibroblasts appear to be prevalent. A persistent urinoma negatively impacts the healing process.

Animals↗
PubMed2004

Prospective comparison of the immunological and stress response following laparoscopic and open surgery for localized renal cell carcinoma.

PURPOSE: We prospectively compared the systemic immune and stress response of patients who underwent laparoscopic total nephrectomy (LRN) (14) and open nephrectomy (ON) (10) for renal cell carcinoma. The ON group comprised open radical (4), open total (2) and open partial (4) nephrectomy cases. MATERIALS AND METHODS: Only patients with no history of cancer or autoimmune disease and American Society of Anesthesiologists score 2 or less who were not using immunosuppressive drugs were selected. Peripheral venous blood was collected preoperatively and intraoperatively, and 24 hours, 2 weeks, 4 weeks and 3 months postoperatively. Blood was analyzed for stress markers (adrenalin, noradrenalin and cortisol), inflammatory response markers (C-reactive protein, white blood count and leukocyte count), lymphocytic response markers (CD3, CD4 and CD8), cytokines interleukin-2 and 4, interferon-alpha and tumor necrosis factor-alpha), HLA-DR expression and the proliferative response to mitogen stimulation using concanavalin A, phytohemagglutinin 10, and pokeweed mitogen. RESULTS: Mean tumor size +/- SD for ON and LRN was 5.6 +/- 2.4 and 4.5 +/- 1.6 cm, respectively (p = 0.21). The trends with time for all measured postoperative parameters were similar in the 2 groups. Inflammatory and stress response markers were statistically similar for in the groups at all time points. A significant difference between the groups was noted for the percentage of CD4+ and CD8+ lymphocytes. However, this difference was present preoperatively and there was no significant absolute change in these 2 parameters. The cytokine response and HLA-DR expression were similar in the 2 groups at all time points. Likewise, the lymphocytic stimulation index for concanavalin A, phytohemagglutinin and pokeweed mitogen were statistically similar for LRN and ON at all time points. CONCLUSIONS: The immunological and stress response after LRN and ON for renal cell carcinoma is similar. The few differences observed in measured parameters likely reflect preoperative differences in baseline and/or the contributory effect of anesthesia.

Carcinoma, Renal Cell↗
PubMed2004

Comparison of guide wires in urology. Which, when and why?

PURPOSE: We compared and contrasted various guide wires with regard to their physical properties as they apply to their use for the access or coaxial passage of other catheters. MATERIALS AND METHODS: Certain 0.035-inch diameter guide wires were tested with regard to tip bending force, shaft bending force, pull force and tip puncture force, namely the Roadrunner PC and polytetrafluoroethylene (PTFE) wire guide (Cook Urological, Spencer, Indiana), Glidewire, Bentson type 15 cm flexible tip PTFE coated guide wire and Amplatz super stiff Urowire XF (Boston Scientific Microvasive, Miami, Florida), Bentson guide wire and Amplatz guide wire (Applied Medical, Rancho Santa Margarita, California) and the PTFE coated Bard guide wire (Bard Urological Division, Covington, Georgia). RESULTS: Regarding guide wires used for access, the Boston Scientific PTFE guide wire with a 15 cm flexible tip required the least amount of force to deflect the tip. Of the 3 cm flexible tip guide wires the Applied Bentson guide wire had the most flexible tip and the Bard guide wire had the stiffest flexible tip. The Boston Scientific Glidewire required the least amount of force to pull from a tortuous pathway and this guide wire also required the greatest force (4 times as much force as the other guide wires) to puncture the aluminum foil (p < 0.001), indicating the safety of its tip. Regarding axial rigidity for the coaxial passage of other catheters over a guide wire, the Boston Scientific Amplatz super stiff guide wire was significantly more resistant to bending than all of the other guide wires that we tested (p < 0.05). CONCLUSIONS: Brand name guide wires designed for the same purpose appear to differ markedly with regard to flexibility, lubricity and shaft stiffness. In general, floppy tip and nitinol based guide wires appear to be best used for access with an emphasis on tip flexibility and a low friction coating, while the stiffer shaft guide wires are selected for coaxial passage of catheters, stents and sheaths.

Equipment Design↗
PubMed2004

Laparoscopic mid sagittal hemicystectomy and bladder reconstruction with small intestinal submucosa and reimplantation of ureter into small intestinal submucosa: 1-year followup.

PURPOSE: We evaluated the long-term results of laparoscopic hemicystectomy and bladder replacement with small intestinal submucosa (SIS) with ureteral reimplantation into the SIS material. MATERIALS AND METHODS: A total of 12 minipigs underwent laparoscopic hemicystectomy. Six pigs underwent bladder reconstruction with SIS and ipsilateral ureteral reimplantation. The remaining 6 control pigs underwent hemicystectomy and primary bladder closure with ipsilateral nephroureterectomy. Preoperative and followup evaluations included blood chemistry, radiography and urodynamic evaluations. The 6, 3, 6 and 9-week, and 12-month followup evaluations included biopsies. At 1 year the animals were sacrificed. Histopathological and contractility studies, and reverse transcriptase-polymerase chain reaction for growth factors and basement membrane components were performed. RESULTS: Bladder capacity and bladder compliance were similar in the 2 groups at all time points. One pig per group died, that is a control at the 9-month evaluation due to an anesthetic complication and an SIS pig 7 months after bladder reconstruction due to spontaneous bladder rupture at the anastomotic site. In the SIS group 4 of 5 surviving pigs had unobstructed reimplanted ureters without evidence of hydroureteronephrosis, while 1 had high grade obstruction at the reimplantation site. Histopathology study after 1 year revealed muscle at the graft periphery and center but it consisted of small fused bundles with significant fibrosis. Nerves were present at the graft periphery and center but they were decreased in number. CONCLUSIONS: Laparoscopic SIS bladder reconstruction and ureteral reimplantation into the SIS after hemicystectomy are technically feasible. However, compared to primary bladder closure no advantage in bladder capacity or compliance was documented.

Animals↗
PubMed2003

Matched pair analysis of shock wave lithotripsy effectiveness for comparison of lithotriptors.

PURPOSE: In an effort to streamline a comparison of the effectiveness of a new lithotriptor with the standard HM3 lithotriptor (Dornier Medical Systems, Inc., Marietta, Georgia) we used a matched pair analysis design. A matched design often provides more efficient estimates (smaller variances) than an unmatched design given the same sample size. MATERIALS AND METHODS: Patients with solitary renal or ureteral calculi treated on a LithoTron shock wave lithotriptor (HealthTronics, Marietta, Georgia) between October 1999 and February 2000 with a minimum followup of 3 months were identified. Evaluable patients treated with the LithoTron were matched using 5 parameters to a data base of patients treated with an unmodified HM3 shock wave lithotriptor between October 1997 and February 2000. Matching criteria consisted of calculus side, calculus location (1 of 7 categories), maximum stone diameter (+/-2 mm.), minimum stone diameter (+/-2 mm.) and patient body mass index (BMI +/-6). When more than 1 match was suitable, matching was directed by random numbers. Following matching, clinical charts and radiographic reports were evaluated for stone clearance and post-shock wave lithotripsy interventions. Stone treatment success was defined as residual fragments less than 2 mm. without need for further intervention. RESULTS: A total of 94 potentially evaluable patients treated with the LithoTron were identified and 38 matched pairs were created. Average maximum stone diameter, minimum stone diameter, and BMI were 9.6 and 9.9 mm., 6.7 and 6.8 mm. and 29.3 and 28.9 kg./m. for HM3 and LithoTron cases, respectively. All calculi were radiopaque and consisted of mixed calcium oxalate monohydrate (19 and 13), calcium oxalate dihydrate (1 and 1) or calcium phosphate (2 and 2) in the HM3 and LithoTron groups, respectively. Patients were not specifically matched on stone composition because of incomplete availability. Overall intervention-free, stone treatment success rate was 79% for the HM3 and 58% for the LithoTron. OR for failure of LithoTron versus HM3 treatment was 3.004 (McNemar test p = 0.08). There were 16 discordant pairs. In 4 cases LithoTron was successful and HM3 failed, and in 12 cases LithoTron failed and HM3 was successful. Subgroup analysis revealed a trend for LithoTron treatment failure for lower pole calculi, calculi 10 mm. or greater and BMI of 30 kg./m. or greater. CONCLUSIONS: In this initial evaluation the HM3, despite a relatively small study sample size, appeared to provide superior clinical results to the LithoTron (p = 0.08). The use of matched pair analysis using a large cohort of patients treated with the HM3 for retrospective matching may allow for accurate determination of the effectiveness of new lithotripsy technology with a relatively small clinical study group.

Adult↗
PubMed2003

Characterization of intrapelvic pressure during ureteropyeloscopy with ureteral access sheaths.

OBJECTIVES: To evaluate the impact of the ureteral access sheath on intrarenal pressures during flexible ureteroscopy in light of the recent resurgence in their use. As such, using human cadaveric kidneys, we studied changes in intrarenal pressure in response to continuous irrigation at different pressures with and without access sheaths of various sizes and lengths. METHODS: This study was performed using seven cadaveric kidneys. In three kidneys the study was done in situ with a 7.5F flexible ureteroscope (URS) passed by itself and then passed through a 10/12F sheath (35 and 55 cm in length), whereas, in four kidneys, due to narrowing of the intramural ureter, the study was done ex vivo using the unsheathed URS and then passing the 7.5F flexible URS via the 10/12F, 12/14F, and 14/16F sheaths (all 35 cm in length). A 10F Cope loop pyelostomy was placed to measure intrapelvic renal pressure. Three sets of 3-minute readings (ie, flow and intrarenal pressure) were taken with the tip of the URS at the distal ureter, middle ureter, and renal pelvis (just above the ureteropelvic junction); the entire process was done at three different irrigant pressure settings: 50, 100, and 200 cm H(2)O. Irrigant flow and intrarenal pressures were measured at all three settings using the URS passed without a sheath and then with the URS passed through the various sheaths positioned at the distal ureter, middle ureter, and renal pelvis. RESULTS: With all of the sheaths, intrapelvic pressure remained low (less than 30 cm H(2)O), and there was a 35% to 80% increase in irrigant flow versus the control unsheathed URS. With the sheath in place, the majority of the irrigant drained alongside the URS and out the sheath. Flow and pressure with the 12/14F sheath were equivalent to the 14/16F sheath. CONCLUSIONS: The 12/14F access sheath provides for maximum flow of irrigant while maintaining a low intrarenal pelvic pressure. Even with an irrigation pressure of 200 cm H(2)O, renal pelvic pressure remained below 20 cm H(2)O.

Equipment Design↗
PubMed2003

Technique for laparoscopic running urethrovesical anastomosis:the single knot method.

OBJECTIVES: To describe a technique for facilitating the urethrovesical anastomosis at the time of laparoscopic radical prostatectomy. METHODS: Two 6-in. polyglycolic acid sutures (one dyed, one white) are tied together at their tail ends and delivered into the operative field by way of a 12-mm port. A running suture is completed from the 6:30 to the 12:00-o'clock position and from the 5:30 to the 12:00-o'clock position, at the end of which a single intracorporeal tie is completed. The catheter is placed before completing the anterior row of sutures; the catheter is left in place for 5 to 7 days. RESULTS: This anastomotic technique has been used in 122 laparoscopic radical prostatectomies and 8 robot-assisted laparoscopic radical prostatectomies. The average time for the anastomosis was 35 minutes (range 14 to 80). All anastomoses were watertight. No symptomatic postoperative urinary leaks have occurred, and no clinically evident clinical bladder neck contractures resulted. CONCLUSIONS: We describe a simple, watertight, running laparoscopic suture technique for accomplishing the urethrovesical anastomosis during laparoscopic radical prostatectomy.

Anastomosis, Surgical↗