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Marshall L Stoller

Publications and source records attributed to Marshall L Stoller.

At least 19 recordsLinked to original sources
PubMed2003

Cytology of morcellated renal specimens: significance in diagnosis and dissemination.

PURPOSE: Controversy surrounds the process of morcellation for retrieving laparoscopically removed specimens. The inability to assess tumor stage, increased difficulty in pathological examination and the potential for tumor spillage are cited as significant disadvantages of the technique. We examined cytological findings in bag washings after laparoscopic nephrectomy for benign and malignant diseases. MATERIALS AND METHODS: We prospectively obtained cytology washings from the retrieval bag after laparoscopic nephrectomy and manual morcellation. In 22 consecutive cases after specimen fragmentation in a LapSac (Cook Urological, Spencer, Indiana) the bag was thoroughly irrigated with 30 cc normal saline. This wash was then processed by ThinPrep (Cytyc Corp., Marlborough, Massachusetts) and stained with Papanicolaou stain. Standard pathological examination of the morcellated specimen was performed to determine renal histology. RESULTS: The histological diagnosis was clear cell renal carcinoma in 10 cases, multicystic renal carcinoma in 2, papillary renal cell carcinoma in 1, angiomyolipoma in 1, and oncocytoma in 1. Bag cytological results were accurate in 9 of 13 patients with carcinoma (69%), while in 3 cytological study provided additional information. In all 9 cases of benign histology, cytological findings were consistent with benign cellular features. Neoplastic cells were easily detected and classified into type and grade. CONCLUSIONS: Cytological examination of LapSac washings after specimen morcellation provided a pathological diagnosis in the majority of patients. This method may complement existing techniques and be useful for increasing the accuracy of pathological analysis of morcellated specimens. In addition, these data suggest that malignant cells are liberated during the morcellation process, which has significant implications for potential tumor dissemination.

Adult↗
PubMed2003

Techniques to optimize vascular control during laparoscopic donor nephrectomy.

OBJECTIVES: To review our experience with laparoscopic donor nephrectomy for kidney transplantation and describe our technique of vessel ligation. METHODS: We retrospectively analyzed the method of renal artery and vein control during the 97 laparoscopic donor nephrectomies performed at the University of California, San Francisco, since November 1999. In addition, we examined both donor and recipient outcomes after nephrectomy and transplantation in this cohort. RESULTS: Currently, we ligate the renal artery and renal vein using a single Hem-o-lok polymer clip and a single Endo-TA stapler, respectively, and divide the vessels using scissors without securing the graft-side vessels. In contrast to using the Endo-GIA stapler, there is no need to trim staples (approximately 5 mm) from the vessels before anastomosis. Excellent vessel length was achieved in all cases without donor complications, and 99% of recipients had long-term graft function. The only major complications (blood transfusion, conversion to open surgery) occurred early in the series when we used the Endo-GIA stapler to control the vessels. CONCLUSIONS: Although adequate vessel length is typically obtained during left donor nephrectomy, additional length can be achieved using our modification. This may facilitate right donor nephrectomy and help reduce complications, potentially increasing the recovery of right kidneys for transplantation. In addition, performing vessel ligation and division in separate steps is simple, does not change ischemic time, and appears to increase safety.

Anastomosis, Surgical↗
PubMed2003

Simplified pure laparoscopic bowel anastomosis.

Laparoscopic bowel anastomosis can be a challenging and time-consuming process. No detailed intracorporeal technique has been well described, and most laparoscopists use an extracorporeal technique, which has many disadvantages. We detail a simple, pure laparoscopic method that creates a capacious isoperistaltic side-to-side enteroenterostomy.

Anastomosis, Surgical↗
PubMed2003

Laterality of symptomatic cystine calculi.

OBJECTIVES: To evaluate patterns of laterality in cystine stone formation to determine whether phenotypic expression of this genetic disease is distributed equally in each kidney. Cystinuria is a genetic defect that may result in the formation of recurrent cystine calculi. Significant nongenetic factors may play a role in the manifestation of this disease. METHODS: Thirty-four patients seen in the Stone Center at the University of California, San Francisco were retrospectively evaluated for treatments and patterns of symptomatic stone formation between 1989 and 2002. A conservative surgical regimen and routine radiographic examinations were used. Treatments were used as a surrogate for development of symptomatic calculi. RESULTS: The mean age at last follow-up was 38.2 years. The mean age at presentation was 18 years. The 34 patients underwent a total of 249 procedures, averaging 7.3 procedures per patient. Of the 34 patients, 29% required only unilateral surgery and formed unilateral symptomatic calculi exclusively (P <0.0001) during their lifetime. Of the 10 patients with unilateral stone formation, 2 (20%) were female and 8 (80%) were male. Of the 24 patients with bilateral stone formation, 12 (50%) were female and 12 (50%) were male. Of the 10 patients with unilateral stone formation, 6 developed left-sided calculi and 4 developed right-sided calculi. CONCLUSIONS: A subset of one third of patients with cystine stone formation will develop unilateral calculi exclusively during their lifetime. Understanding why the contralateral side did not form stones may provide insight into novel prophylactic regimens. The etiology of symptomatic unilateral cystine nephrolithiasis is unknown, but anatomic and external triggers should be considered.

Adult↗
PubMed2003

Laparoscopic radical nephrectomy for suspected renal cell carcinoma in dialysis-dependent patients.

OBJECTIVES: To characterize the treatment and outcomes of laparoscopic nephrectomy for suspected renal cancer in patients with dialysis-dependent renal failure. Laparoscopic nephrectomy is currently an accepted modality in the treatment of renal cell carcinoma in many patients. However, the indications for the minimally invasive approach in patients with renal dysfunction are unclear. End-stage renal disease has multiple manifestations associated with increased operative morbidity that are potentially amplified during laparoscopy. METHODS: We reviewed our single-center experience for performing laparoscopic nephrectomy in patients with renal failure. Of patients receiving dialysis and having a kidney removed laparoscopically, 7 underwent the operation for suspected renal carcinoma because of a solid mass on imaging. The preoperative, intraoperative, and postoperative considerations were reviewed. RESULTS: Of the 7 patients, 5 (71%) underwent successful removal of the kidney by laparoscopy. The amount of blood loss (120 mL) and the median time to discharge after surgery (3 days) were comparable to published data and our experience in patients with normal renal function; however, the operative time (mean 294 minutes) was longer. No recurrences had been detected at the last follow-up examination (median 21 months, range 18 to 51). Despite meticulous attention to perioperative and anesthetic considerations, two complications were observed-ileus and necrotizing fasciitis of the flank. CONCLUSIONS: Pure laparoscopic nephrectomy for renal malignancy is feasible in patients with end-stage renal failure. However, this population is at increased risk of complications, despite maintaining the advantages of reduced blood loss and shorter hospitalization. The decision to proceed with laparoscopy and the selection of the specific surgical approach (transperitoneal or retroperitoneal) should be based on both surgeon experience and patient factors. In addition, careful preoperative preparation and intraoperative anesthetic management are crucial.

Adult↗
PubMed2003

Hellström technique revisited: laparoscopic management of ureteropelvic junction obstruction.

OBJECTIVES: To present our experience with the treatment of adult ureteropelvic junction (UPJ) obstruction using a laparoscopic Hellström vascular relocation technique. METHODS: Transperitoneal laparoscopy was performed in 35 patients for the management of UPJ obstruction. In 9 cases, we identified crossing lower pole vessels and performed the Hellström technique. We discuss our indications, intraoperative techniques, and outcomes when performing only vascular relocation in these patients. RESULTS: All 9 patients presented with long-standing flank pain and were identified as having UPJ obstruction (7 primary, 2 secondary) on radiographic imaging. The intraoperative decision to perform the Hellström technique was based on the presence of the crossing vessels, a grossly normal appearance of the ureter and UPJ, and a small renal pelvis. The crossing vessels were completely mobilized, displaced cephalad, and fixed using intracorporeal sutures. The mean operative time and blood loss was 164 minutes and 15 mL, respectively. At a mean follow-up of 19 months (range 14 to 31), the patients were asymptomatic with no evidence of obstruction on Lasix nuclear renography. CONCLUSIONS: Traditional treatment of UPJ obstruction, with or without crossing vessels, has been accomplished by pyeloplasty. Dismembered pyeloplasty is a standard method in cases of associated crossing vessels; however, we propose that the Hellström technique be considered in cases in which the ureter appears normal and the pelvic anatomy is unfavorable for transection and anterior reanastomosis of the ureter and pelvis. These considerations are particularly relevant during the laparoscopic approach in which intracorporeal suturing and knot tying are technically challenging.

Adolescent↗
PubMed2003

Pathologic sampling of laparoscopically morcellated kidneys: a mathematical model.

BACKGROUND AND PURPOSE: Kidney morcellation permits tissue removal through a port site; however, standard methods of histopathologic examination of the numerous specimen fragments thus produced have not been established. We developed a model to guide pathologic evaluation of the morcellated kidney. MATERIALS AND METHODS: A mathematical model was created to determine the quantity of morcellated tissue needed to establish a diagnosis. Inputs into the equation included estimated lesion size, total specimen volume, and the desired certainty of identifying at least a portion of the lesion on pathologic analysis. Nomograms were calculated to illustrate the model and provide clinically relevant guidelines. RESULTS: The hypergeometric distribution was used to develop the formula: P = 1 - (1 - k/N)(n), where k/N represents the fraction of total specimen with tumor, n is the amount of specimen that must be sampled to yield a diagnosis, and P is the probability of encountering the tumor in the sampled tissue. The model provided nomograms that were feasible and would guide a practical approach to the pathologic analysis of laparoscopically morcellated specimens. CONCLUSIONS: The increasing application of laparoscopy to the removal of solid organs with suspected tumors has raised several important issues. Morcellation of these specimens precludes traditional pathologic examination and necessitates an alternative method of specimen sampling and diagnosis. We describe a novel, systematic model to assist in the histopathologic examination of morcellated specimens. Issues of pathologic staging remain unresolved, but this sampling system provides a nonarbitrary framework to help arrive at a histologic diagnosis.

Humans↗
PubMed2003

Infection and urinary stones.

PURPOSE OF REVIEW: Despite modern antibiotic therapy and technological advances in lithotripsy, the presence of infection in urinary stone patients as well as infectious stones are still a significant cause of morbidity and mortality. Many new investigations are focusing on the pathogenesis and treatment of these difficult cases. RECENT FINDINGS: Most of the current literature on the subject focuses on pathogenesis of infectious urinary stones. The remaining literature highlights difficult cases, outcomes of treatments, and overall reviews of the subject. SUMMARY: Recent findings lend more theories as to how infection leads to stone formation. Further investigation is critically needed to improve the outcomes of patients suffering from infections with urinary stones and infectious stones.

Acute Disease↗
PubMed2003

Expanded experience with laparoscopic nephrectomy and autotransplantation for severe ureteral injury.

PURPOSE: Complex injuries of the upper ureter with significant loss of length are difficult to manage. Traditional options include nephrectomy, bowel interposition and autotransplantation. The advent of laparoscopic donor nephrectomy has created a new option when preservation of functioning renal parenchyma is desirable. We update our experience with severe iatrogenic ureteral injuries requiring laparoscopic nephrectomy and autotransplantation. MATERIALS AND METHODS: Seven patients with severe ureteral injuries were referred for definitive management. In all cases preoperative evaluation demonstrated comparable split renal function and anatomy not amenable to routine reconstruction. Transperitoneal laparoscopic nephrectomy and autotransplantation to the ipsilateral pelvis were attempted. RESULTS: Of the patients 5 had a history of nephrolithiasis with intervention resulting in the ureteral injury and 5 underwent prior endoscopic or open management of the defects. All cases were associated with dense perinephric and perihilar fibrosis. Operative and warm ischemic times averaged 508 and 5 minutes, respectively. After ex vivo graft preparation, ureteral and vessel length and quality were adequate for transplantation in 6 cases. In the other patient the renal pelvis was not amenable for reconstruction. Urinary drainage consisted of ureteroneocystostomy in 2 cases and ipsilateral ureteroureterostomy in 4. There were no intraoperative complications and all grafts functioned immediately. Hospitalization averaged 6.4 days. At a mean followup of 17 months imaging studies demonstrated functioning renal autographs with a mean decrease in serum creatinine of 5%. CONCLUSIONS: Laparoscopic nephrectomy in conjunction with autotransplantation is a viable option for severe proximal ureteral loss. Acceptable perioperative morbidity and excellent graft function were obtained in all cases when the kidney was transplanted. Close cooperation with a transplant team is crucial to coordinate graft harvest, ensure appropriate organ preparation and select the optimal urinary anastomosis.

Adult↗
PubMed2003

Infections and urinary stone disease.

The relationship between urinary infections and stone formation has been recognized since antiquity and it has been over a century since bacterial degradation of urea was postulated to cause struvite stones. Specific therapy for urease-producing bacteria, such as urease-inhibitors and antibiotics, has allowed for treatment for this subset of urinary stones. Future directions for research include development of novel urease-inhibitors and chemicals to enhance the protective glycosaminoglycan layer. An improved understanding of the pathogenesis of calcium-based stones has led to the discovery of potential roles for nanobacteria and Oxalobacter formingenes. Methods of altering intestinal regulation of oxalate by reintroduction of lactic acid bacteria may significantly impact the treatment of calcium oxalate stones. The use of catheters, both urethral and ureteral, is common in the urinary tract and is associated with significant morbidity, primarily from associated infections. Catheters to prevent bacterial colonization and formation of biofilms have been created using various coatings, including ciprofloxacin, hydrogel, and silver. Use of these types of catheters may minimize infections and encrustation inherent with their placement in the urinary tract.

Animals↗
PubMed2002

Uric acid nephrolithiasis: current concepts and controversies.

PURPOSE: Uric acid calculi with or without a calcium component comprise a significant proportion of urinary stones. Knowledge of the pathophysiology of stone formation is important to direct medical treatment. The aim of this review is to provide an update on the epidemiology, pathophysiology and management of uric acid renal stones. MATERIALS AND METHODS: A MEDLINE search was performed on the topic of uric acid stones. Current literature was reviewed with regard to the epidemiology, pathophysiology, associated medical conditions and management of uric acid stones. RESULTS: The incidence of uric acid stones varies between countries and accounts for 5% to 40% of all urinary calculi. Hyperuricuria, low urinary output and acidic urine are well known contributing factors. However, the most important factor for uric acid stone formation is persistently acidic urine. Gout and myeloproliferative disorders are associated with uric acid stones. Why most patients with gout present with acidic urine yet only 20% have uric acid stone formation remains unclear. The pathophysiological basis for persistent urine acidity also remains unclear although various mechanisms have been proposed. Urinary alkalization with potassium citrate or sodium bicarbonate is a highly effective treatment, resulting in dissolution of existing stones and prevention of recurrence. CONCLUSIONS: Acidic urine is a prerequisite for uric acid stone formation and growth. Medical management with urinary alkalization for stone dissolution and prevention of recurrence is effective and should be the cornerstone of treatment.

Cross-Sectional Studies↗
PubMed2002

Donor-gifted allograft urolithiasis: early percutaneous management.

OBJECTIVES: To describe our successful early management of donor-gifted nephrolithiasis by percutaneous nephrolithotomy. Donor-gifted nephrolithiasis is a rare and frustrating complication of renal transplantation. In the past, initial conservative management with relief of obstruction and shock wave lithotripsy has been recommended. METHODS: We treated 3 cases of donor-gifted cadaveric kidney transplant stones by a percutaneous approach 1 to 2 months postoperatively. Two patients presented with hydronephrosis-associated renal deterioration and febrile urinary tract infection, and the third was diagnosed incidentally on routine postoperative ultrasonography. RESULTS: Percutaneous nephrolithotomy was performed with ultrasound stone fragmentation after initial nephrostomy tube drainage in 1 patient. In the second patient, the stone was successfully removed in a basket in an antegrade fashion. The third patient's ureteral stone was successfully removed by antegrade ureteroscopy. Postoperatively, no residual stones were noted on nephrostography, and renal function returned to normal. CONCLUSIONS. Post-transplant renal calculi can be managed successfully by percutaneous techniques in the early postoperative period and renal function can be salvaged. Pretransplant renal sonography may be considered to limit donor-gifted calculi.

Cadaver↗
PubMed2002

Laparoscopic intracorporeal square-to-slip knot.

We review a laparoscopic, intracorporeal technique of securing the square knot. It is useful when a surgeon's knot is insufficient to maintain tissue approximation. Advantages include the use of standard tying methods, lack of extracorporeal knot creation or need for a pushing device, and ability to secure the knot in difficult locations.

Humans↗
PubMed2002

Complete laparoscopic ileal cystoplasty.

INTRODUCTION: Laparoscopic enterocystoplasty provides a minimally invasive approach to bladder augmentation in the patient with a neurogenic bladder. In previously published reports, portions of the procedure were performed extracorporeally. We report our technique of complete intracorporeal laparoscopic enterocystoplasty. TECHNICAL CONSIDERATIONS: Important elements of the operation include (a) preoperative evaluation of patient compliance and videourodynamic studies; (b) cystoscopic placement of externalized ureteral stents; (c) transperitoneal placement of five radially dilating trocars; (d) identification of the cecum; (e) proximal mobilization of ileum sufficient for pelvic placement; (f) measurement of ileal length with segment of precut vessel loop; (g) vertical cystotomy after incising peritoneum and entering the space of Retzius; (h) ileal division and side-to-side anastomosis using endoscopic gastrointestinal anastomosis staplers; (i) detubularization and freehand intracorporeal suturing into a U-shaped configuration; (j) fixing ileal patch at the 6 and 11-o'clock positions; (k) completion of ileal-bladder anastomosis in quadrants with running sutures; (l) irrigation of bladder and placement of a closed suction drain in the pelvis; and (m) cystogram 4 weeks postoperatively. CONCLUSIONS: Pure laparoscopic enterocystoplasty is an advanced procedure that is technically feasible and yields excellent results, but has unproven benefits. We perform the entire operation intracorporeally with traditional instruments and do not rely on suturing devices or extracorporeal knots. Additional experience and technological developments may result in routine laparoscopic urinary augmentation and continent diversion.

Anastomosis, Surgical↗
PubMed2002

Calcium nephrolithiasis: effect of water hardness on urinary electrolytes.

OBJECTIVES: To analyze the impact of water hardness from public water supplies on calcium stone incidence and 24-hour urine chemistries in patients with known calcium urinary stone formation. Patients are frequently concerned that their public water supply may contribute to urinary stone disease. Investigators have documented an inverse relationship between water hardness and calcium lithogenesis. Others have found no such association. METHODS: Patients who form calcium stones (n = 4833) were identified geographically by their zip code. Water hardness information from distinct geographic public water supplies was obtained, and patient 24-hour urine chemistries were evaluated. Drinking water hardness was divided into decile rankings on the basis of the public water supply information obtained from the Environmental Protection Agency. These data were compared with patient questionnaires and 24-hour urine chemistries. The calcium and magnesium levels in the drinking water were analyzed as independent variables. RESULTS: The number of total lifetime stone episodes was similar between patients residing in areas with soft public water and hard public water. Patients consuming the softest water decile formed 3.4 lifetime stones and those who consumed the hardest water developed 3.0 lifetime stones (P = 0.0017). The 24-hour urine calcium, magnesium, and citrate levels increased directly with drinking water hardness, and no significant change was found in urinary oxalate, uric acid, pH, or volume. CONCLUSIONS: The impact of water hardness on urinary stone formation remains unclear, despite a weak correlation between water hardness and urinary calcium, magnesium, and citrate excretion. Tap water, however, can change urinary electrolytes in patients who form calcium stones.

Adolescent↗
PubMed2002

Muconephrosis.

We report a case of a mucus-filled kidney (muconephrosis) encountered during laparoscopic nephrectomy for presumed xanthogranulomatous pyelonephritis. Conversion to open nephrectomy and en-bloc right hemicolectomy were necessary because of severe perinephric fibrosis and suspected renal-enteral fistula. Pathologic examination revealed a renal pelvic villous adenoma and diffuse intestinal metaplasia of the urothelium; no enteral communication or gastrointestinal pathologic features were found. Urothelial villous adenoma is extremely rare, and one should consider neoplastic etiologies, including appendiceal mucinous cystadenocarcinoma and mucus-secreting adenocarcinoma of the renal pelvis, in directing the appropriate management of muconephrosis.

Adenoma, Villous↗