Biomedical subjects
Publications and source records attributed to Robert Marcovich.
We present a case of a prolonged urine leak after partial nephrectomy successfully treated by retrograde ureteroscopic injection of fibrin sealant. The technical aspects of retrograde instillation of sealant into the lower renal pole and outcome are discussed.
OBJECTIVES: To determine current practice patterns in the surgical treatment of ureteropelvic junction obstruction (UPJO) among urologists in the United States. METHODS: Using the American Urological Association directory, an electronic mail survey regarding the surgical management of UPJO was sent to 1040 urologists in the United States with an electronic mail address listed in the roster. RESULTS: The response rate was 37.6%. Of the respondents, 67.4% were in community practice and 32.6% in academic practice. Nearly 53% of the respondents would perform a workup for a crossing vessel before definitive therapy; if no crossing vessel was found, 43.5% would consider Acucise endopyelotomy as the first-line procedure. However, if a crossing vessel was found, 57.4% would perform open pyeloplasty and 34.3% would choose laparoscopic pyeloplasty as their first-line procedure. If pyeloplasty was chosen, community urologists preferred open pyeloplasty (77.6%), and academic urologists preferred laparoscopic pyeloplasty (66.9%). The surgeon's training and experience was the most influential factor in choosing between laparoscopic and open pyeloplasty. If the patient had a failed endopyelotomy in the past, most respondents (90.8%) would perform pyeloplasty for definitive treatment of the UPJO. CONCLUSIONS: Demonstration of a crossing vessel remains an important factor in determining the course of management of a UPJO. During the past 5 years, a growing number of urologists in both academic and nonacademic practices have been performing laparoscopic pyeloplasty for the management of UPJO in adults. Several factors, especially the surgeon's training, have an impact on the choice of procedure. Open pyeloplasty is still performed by a significant number of urologists. These data may be useful in designing physician education programs and/or future investigations to help define standard treatment practices for UPJO.
BACKGROUND AND PURPOSE: Long strictures of the proximal ureter are difficult to manage, and circumferential replacement with various natural and synthetic materials has been unsuccessful. We sought to use cultured autologous cells seeded onto graft material for proximal-ureteral replacement. Additionally, we wished to determine if urothelial cell-seeded de-epithelialized small bowel would generate adequate ureteral replacement. MATERIALS AND METHODS: Three sets of experiments were performed. First, autologous pig-bladder smooth-muscle and urothelial cells were expanded in culture on large sheets of multilayer small-intestinal submucosa (SIS). These sheets were then tubularized and used to replace a 5-cm segment of proximal ureter in pigs. Second, autologous cells harvested from the bladders of Beagle dogs were cultured and seeded on porcine ureteral acellular matrix, which was used to replace a 3-cm segment of ureter in dogs. Segments were wrapped in omentum to enhance vascularity. Third, a de-epithelialized small-bowel segment seeded with autologous bladder-epithelial cells was transversally retubularized (Monti) into a 4-cm ureteral replacement. Follow-up studies consisted of retrograde pyelography, serum chemistry assays, hematoxylin/eosin studies, and immunohistopathologic examination using antibodies against alpha-smooth-muscle actin and pancytokeratin AE1-AE3. RESULTS: Coculture of urinary-tract cells on large segments of SIS failed to create adequate ureteral replacement. All grafts were contracted and stenotic, with complete obstruction of the ipsilateral renal unit. Similar results were seen in the Beagles. Despite clinical obstruction and gross contraction of the graft, a circumferential muscular ureteral wall lined with multilayer transitional epithelium was present. Urotheliumseeded de-epithelialized Monti bowel segments resulted in patent ureteral replacement without hydroureteronephrosis and with normal renal function, serum electrolytes, and acid-base balance. However, bowel mucosa fully regenerated, with multilayer transitional epithelium growing adluminally in continuity with the proximal and distal anastomotic sites. CONCLUSIONS: Seeding of ureteral grafts with autologous bladder cells does not promote success in two largeanimal models using different xenogenic acellular matrices. However, muscle and urothelium regeneration occurs with ureteral acellular matrix in the dog. Urothelium-seeded de-epithelialized Monti bowel segments may be an acceptable substitute for long proximal ureteral segments. Further technical refinements are required to replace the bowel mucosa completely with normal urothelium.
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OBJECTIVES: To review our perioperative experience with patients presenting with high-risk bladder cancer who had undergone prior therapy for prostate cancer. With the increase in diagnosis and subsequent treatment of prostate cancer, more patients presenting with high-risk bladder cancer have undergone prior therapy for prostate cancer. Radical cystectomy in these patients can be technically challenging and may be associated with added morbidity. METHODS: A retrospective review of 458 patients treated with radical cystectomy between January 1993 and January 2002 revealed 29 patients (mean age 72 years) who had received definitive treatment for prostate cancer prior to cystectomy for bladder carcinoma. The initial treatment in this cohort was radical prostatectomy or external beam radiotherapy in 12 (41%) and 17 (59%) men, respectively. Cystectomy was performed for transitional cell carcinoma in 25 (86%), small cell carcinoma in 2 (6%), and sarcoma in 2 (6%) patients. RESULTS: At the time of cystectomy, the mean blood loss was 1175 mL (range 275 to 3500), and the median length of hospitalization was 8 days (range 4 to 23). No intraoperative or perioperative deaths occurred in this cohort. Twenty-seven early complications were identified in 16 (55%) of 29 patients; no rectal injuries occurred. Patients with prior radiotherapy had a higher rate of extravesical bladder carcinoma (60%) than those patients treated with prior prostatectomy (33%). An orthotopic neobladder diversion was created in 5 patients (17%). CONCLUSIONS: Patients with bladder cancer previously treated for prostate cancer with external beam radiotherapy or radical prostatectomy have an increased risk of perioperative complications compared with patients undergoing cystectomy without prior therapy. This risk is not prohibitive, and radical cystectomy should remain the treatment of choice for high-risk bladder cancer in this population. Furthermore, orthotopic urinary diversion may be a reasonable option and should be considered in select patients.
OBJECTIVES: To compare the safety and efficacy of morcellation with the electrical prostate morcellator (EPM) or manual morcellation of the kidney, using an internal view within the morcellation sac. METHODS: Thirty porcine kidneys, mean renal mass 174.5 g, were divided into three groups of 10. All morcellations were performed inside the LapSac. Groups 1 and 2 underwent morcellation using the EPM, monitored inside the LapSac using the nephroscope and outside the LapSac with the laparoscope, respectively. Group 3 underwent manual morcellation with ring forceps. The groups were assessed for morcellation time, fragment size, and LapSac integrity. RESULTS: In group 1, one pinhole perforation occurred; in group 2, nine perforations occurred (five large and four pinhole). No perforations occurred (P <0.001) in group 3 (manual morcellation). The mean morcellation time for groups 1 through 3 was, respectively, 86.9, 47.1, and 15.1 minutes (P <0.0001). The corresponding mean fragment size was 0.011, 0.015, and 1.36 g. The difference in mean fragment size was significantly different between the manual morcellation group and the EPM groups (P <0.001), but not between the two EPM groups (P = 0.12). CONCLUSIONS: Manual morcellation was safe, fast, and superior to morcellation with the EPM monitored either inside or outside the LapSac. The high rate of LapSac perforation precludes the use of EPM after laparoscopic radical nephrectomy in the clinical forum.
OBJECTIVES: To determine current practice patterns in the surgical treatment of ureteropelvic junction obstruction in the United States and Canada. METHODS: An e-mail survey was sent to 56 academic endourologists regarding the number of procedures performed in the previous year for ureteropelvic junction obstruction, factors considered in the choice of procedure, and whether community urologists in their area were performing laparoscopic pyeloplasty or endopyelotomy. RESULTS: The response rate was 66% (37 of 56). More respondents were performing endopyelotomy (91%) than laparoscopic pyeloplasty (51%), and nearly one half were performing open pyeloplasty. The mean number of procedures performed by respondents in the previous year was 9.5 endopyelotomies, 4 laparoscopic pyeloplasties, and 2.5 open pyeloplasties. A number of factors had an impact on the practitioners' choice of procedure, including the presence of a crossing vessel and massive hydronephrosis, secondary ureteropelvic junction obstruction, the surgeon's training, procedure cost, operative time, expected success rate, degree of invasiveness, and patient preference. Nearly one fifth of respondents said they would choose laparoscopic pyeloplasty as first-line therapy regardless of anatomic considerations. Seventy-eight percent stated that community urologists in their area were performing endopyelotomy routinely or occasionally compared with only 3% who stated community urologists in their area were performing laparoscopic pyeloplasty. CONCLUSIONS: Laparoscopic pyeloplasty is still in its early stages. Although laparoscopic pyeloplasty has a greater success rate, endopyelotomy continues to be more commonly performed in academic centers. Laparoscopic pyeloplasty has not yet made significant inroads into community practice. Several factors, especially the surgeons' training, have an impact on the choice of procedure. Open pyeloplasty is still performed by a significant number of academic endourologists.
OBJECTIVES: New designs have improved the ability of flexible ureteroscopes to assess the upper urinary tract. However, limitations of tip deflection may interfere with diagnosis and treatment of lower pole renal pathologic features and smaller working channels may impair irrigant flow. Our purpose was to compare the new flexible ureteroscopes with prior models to determine whether engineering advances have overcome these problems. METHODS: Two newly released flexible ureteroscopes, the ACMI DUR-8 Elite and the Storz 11278AU, were compared with four other ureteroscopes, the ACMI DUR-8, Storz 11274AAU, Olympus URF-P3, and Wolf 9F. Active tip deflection, irrigation flow rates, and intraluminal pressures with and without various endoscopic tools were assessed. The specifications, purchase prices, and repair costs were obtained from the individual manufacturers. Also, the field of view and screen image size of each scope were compared. RESULTS: The ACMI DUR-8 Elite and Storz 11278AU had improved tip deflection of 79 degrees and 144 degrees, respectively, from previous ureteroscopes. Although the tip deflections of all ureteroscopes were compromised by the insertion of endoscopic tools, new ureteroscopes were less affected. With a 3F basket within the working channel, the ACMI DUR-8 Elite and the Storz 11278AU had a loss of downward deflection of only 0.7% and 2.8% compared with a loss of 9.6% and 5.0% for their older models, respectively. However, the flow rate of these new instruments was decreased. CONCLUSIONS: The new flexible ureteroscopes have significantly better active tip deflection than previous models, both with and without endoscopic instrumentation inserted. However, improved flexibility comes at the expense of a decreased flow rate.
BACKGROUND AND PURPOSE: Laparoscopic bowel injuries are rare but potentially fatal if recognition is delayed. Unlike the situation after open surgery, patients with unrecognized bowel injury after laparoscopy do not present with the typical "acute surgical abdomen." We investigated monocyte, neutrophil, and lymphocyte apoptosis as indicators of the immune response and whether this response is stimulated or suppressed by laparoscopic bowel injury compared with bowel injury induced during open surgery. MATERIALS AND METHODS: After an animal protocol was approved, laparoscopy was performed in a rabbit model. A total of 44 animals were divided into four groups of 11 rabbits each. Laparoscopic bowel injury was created using 30-W electrocautery at 0 (control), 1, and 5 hours after induction of pneumoperitoneum. Bowel injury was created in the fourth group during open laparotomy. Animals were euthanized at 0, 1 day, 1 week, or 2 weeks after surgery. Apoptosis was assessed by staining the nuclei of blood cells with H-33342 dye. RESULTS: At 1 week, neutrophil, monocyte, and lymphocyte apoptosis levels were 2.4- to 5-fold lower after laparoscopy (1-hour pneumoperitoneum) compared with open surgery. However, at 2 weeks, the percentage of apoptosis had equalized in the two groups. Interestingly, with longer laparoscopic procedures (5 hours), the percentage of apoptosis at 0 and 1 day more closely approached that seen after open surgery. At 2 weeks, there was a significant difference in apoptosis levels in all cell types between the experimental groups compared with controls (P < 0.001). No animals undergoing a 5-hour open procedure survived to 2 weeks after bowel injury. CONCLUSIONS: Open surgery resulted in a significant increase in programmed cell death compared with controls in the immediate postoperative period following bowel injury. Laparoscopic surgery produced a delayed response and after 2 weeks with bowel perforation approached open surgery levels. The difference in the degree of cellular death may be secondary to a smaller degree of stimulation of the immune response in laparoscopic surgery.
OBJECTIVES: To determine the presence or absence of air in the renal collecting system 48 hours following percutaneous nephrolithotomy (PCNL). METHODS: The study was based on a review of the records of the last 100 consecutive patients undergoing PCNL for stone extraction. Two urologists and a uroradiologist reviewed post-PCNL nephrostogram films and determined the presence or absence of air in the urinary tract. RESULTS: Nephrostography was routinely performed 48 hours after PCNL, and all films of the 100 patients were reviewed. Gas was detected in 98 (98%) of the 100 cases that appeared as gas pyelograms outlining the renal calyces. Of the 98 cases, 33 (34%) demonstrated gas in the upper calyx, 10 (10%) in the middle calyx, 12 (13%) in the lower calyx, and 43 (44%) in more than one calyx. Gas was not detected in the renal parenchyma or perirenal areas. CONCLUSIONS: Gas is present within the renal collecting system 48 hours after a percutaneous procedure. Prospective studies should be performed to document the amount of time needed for complete resolution of gas from the collecting system.
PURPOSE: Radio frequency ablation (RFA) has been used as a minimally invasive alternative to nephrectomy for small renal tumors. Questions have arisen regarding the accuracy of cell viability determination on standard hematoxylin and eosin (H & E) staining. We investigated and compared the histological characteristics of RF ablated renal tissue using nicotinamide adenine dinucleotide (NADH) and H & E staining. MATERIALS AND METHODS: Ten porcine kidneys underwent laparoscopic RFA of the upper and lower poles using a 2 (8) or 3 cm (2) protocol with 2 cycles of 90 W, target temperature 105C and treatment time 5.5 minutes per cycle. Following tract ablation the kidneys were immediately harvested, gross lesion size was measured and tissue was processed for standard H & E and NADH staining. RESULTS: H & E staining of ablated tissue revealed a number of alterations in renal tubular histology. However, all of these findings were focal with areas of parenchyma that appeared well preserved. Corresponding areas on NADH processed sections showed the complete absence of staining, indicating the lack of cellular viability. There were no skip areas noted on NADH processed sections and treated portions demonstrated a well demarcated border of ablation. CONCLUSIONS: While RFA produces discernible histological changes acutely on H & E, these alterations are variable and patchy, and they alternate with areas of well preserved tissue. Therefore, NADH staining should always be used to assess and verify cellular death in RFA lesions. In this study no skip areas of viable cells were noted within areas of ablated tissue on NADH staining.
Introduction of minimally invasive techniques has revolutionized the surgical management of renal calculi. Extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy are now both well-established procedures. Each modality has advantages and disadvantages, and the application of each should be based on well-defined factors. These variables include stone factors such as number, size, and composition; factors related to the stone's environment, including the stone's location, spatial anatomy of the renal collecting system, presence of hydronephrosis, and other anatomic variables, such as the presence of calyceal diverticula and renal anomalies; and clinical or patient factors like morbid obesity, the presence of a solitary kidney, and renal insufficiency. The morbidity of each procedure in relation to its efficacy should be taken in to account. This article will review current knowledge and suggest an algorithm for the rational management of renal calculi with shock wave lithotripsy and percutaneous nephrolithotomy.