Simultaneous bilateral retrograde intrarenal surgery for stone disease in patients with significant comorbidities.

BACKGROUND AND PURPOSE: Advances in endoscopic equipment have allowed urologists to access stones in virtually any location in the upper tracts. Where clinically appropriate, this approach may represent the preferred treatment option, regardless of stone size. We report the first description of simultaneous bilateral retrograde intrarenal surgery (SB-RIRS) in patients with both significant upper-tract stone burdens and comorbidities such as morbid obesity or heart disease. PATIENTS AND METHODS: Between September 2003 and April 2004, three men and one woman with an average of 62 years underwent a total of seven sessions of SB-RIRS. All four patients were referred from other urologists after failing prior treatments, including shockwave lithotripsy (five sessions) and RIRS (two sessions). The average stone burden was 8.8 cm. The procedures were performed by two surgeons operating simultaneously using two sets of video/holmium laser equipment. Flexible (7.5F) ureteroscopes were used to fragment and basket stone debris without the use of ureteral access sheaths. RESULTS: Three patients underwent a scheduled second-stage procedure to ensure adequate stone clearance. The average total and SB-RIRS-specific operative times were 256 and 131 minutes for the initial procedure and 235 and 95 minutes for the second-stage procedure, respectively. No major complications were noted. CONCLUSION: Simultaneous bilateral RIRS is an appropriate treatment option for stone patients with significant comorbidities.

Bladder reconstitution with bone marrow derived stem cells seeded on small intestinal submucosa improves morphological and molecular composition.

PURPOSE: Tissue engineering has been used for bladder augmentations with small intestinal submucosa (SIS). Although favorable short-term outcomes have been reported, long-term followup has been poor. We investigate whether tissue engineering with stem cells improves the morphological and genetic composition. MATERIALS AND METHODS: A total of 33 Lewis rats (Harlan Laboratories, Indianapolis, Indiana) were used to investigate bladder augmentations with 4-layer SIS in certain groups, including the control group (sham operation), partial cystectomy with oversewn defect group (OG), augmentation with unseeded SIS group (USG) and augmentation with stem cell seeded SIS group (SSG). Bladders from 4 rats per group were harvested 1 and 3 months after surgery. Morphological analyses were performed using Masson's trichrome and immunohistochemical staining with cytokeratin AE1/AE3, smooth muscle alpha-actin and S100. Gene expression was evaluated using quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) for collagen I (CI), collagen III (CIII), cytokeratins 8 and 19, and smooth muscle myosin heavy chain (MHC). RESULTS: At 1 month trichrome staining revealed collagen admixed with indiscrete cells and morphology similar to that in controls in USG and SSG, respectively. Discrete smooth muscles fascicles and S100 staining were found in all groups except USG. Organized urothelium with increased basal cell layer staining was present in controls and SSG only. At 3 months increased collagen formation was present in OG and USG. Immunostaining showed hyperplasia of the urothelium with increased staining of the basal cell layer, discrete muscle fascicles and positive nerve staining in all groups. Using quantitative RT-PCR expression levels in SSG were more improved than in USG, especially for CI, CIII and MHC. This was further evident at 3 months when CI and CIII were over expressed in OG and USG but not in the control group or SSG. Furthermore, RT-PCR showed that cytokeratins 8 and 19, and MHC had greater expression levels in SSG than in USG. CONCLUSIONS: Bladder reconstitution occurs more rapidly using stem cell seeded SIS. Although in USG and SSG all 3 cellular constituents appear to develop by 3 months, only SSG had gene expression levels similar to those in controls. The results suggest an explanation for the fibrosis noted in unseeded SIS bladder augmentations and the possible solution using stem cells.

Looped silk tie: surgical technique for management of the renal vein during laparoscopic live-donor nephrectomy.

Laparoscopic live-donor nephrectomy has revolutionized the field of kidney transplantation and has been adopted in many tertiary centers as the method of choice in procuring kidneys. While standard techniques for laparoscopic live-donor nephrectomy have been well described in the literature, there continues to be ample discussion about renal-vein ligation. Endo-GIA and other commonly used vascular stapling devices can be costly and prone to mechanical failures and may not be applicable in certain anatomic situations. Vascular clips, although simple to use for arteries, are difficult to apply to large renal veins. To address these issues, we describe a simple, cost-effective method of control that can be used for both right and left renal veins, using a loop constructed from a 0 silk tie.

Simultaneous bilateral retrograde intrarenal surgery for bilateral complex upper tract stone disease.

Recent advances in retrograde endoscopy have greatly expanded the role of minimally invasive surgery in addressing upper tract stone disease. In an attempt to decrease patient morbidity further, we present our initial experience with simultaneous bilateral retrograde intrarenal surgery in a patient with complex bilateral upper tract stones.

Newly designed laparoscopic retractable dissector and suture passer.

We introduce a novel laparoscopic instrument that performs as a dissector and retractable suture passer in preparation for intracorporeal knot tying. The newly designed instrument was developed at our institution to duplicate techniques of vessel ligation in open surgery.

Laparoscopic skills training using a webcam trainer.

PURPOSE: Many sophisticated and expensive trainers have been developed to assist surgeons in learning basic laparoscopic skills. We developed an inexpensive trainer and evaluated its effectiveness. MATERIALS AND METHODS: The webcam laparoscopic training device is composed of a webcam, cardboard box, desk lamp and home computer. This homemade trainer was evaluated against 2 commercially available systems, namely the video Pelvitrainer (Karl Storz Endoscopy, Culver City, California) and the dual mirror Simuview (Simulab Corp., Seattle, Washington). The Pelvitrainer consists of a fiberglass box, single lens optic laparoscope, fiberoptic light source, endoscopic camera and video monitor, while the Simuview trainer uses 2 offset, facing mirrors and an uncovered plastic box. A total of 42 participants without prior laparoscopic training were enrolled in the study and asked to execute 2 tasks, that is peg transfer and pattern cutting. Participants were randomly assigned to 6 groups with each group representing a different permutation of trainers to be used. The time required for participants to complete each task was recorded and differences in performance were calculated. Paired t tests, the Wilcoxon signed rank test and ANOVA were performed to analyze the statistical difference in performance times for all conditions. RESULTS: Statistical analyses of the 2 tasks showed no significant difference for the video and webcam trainers. However, the mirror trainer gave significantly higher outcome values for tasks 1 and 2 compared to the video (p = 0.01 and <0.01) and webcam (p = 0.04 and <0.01, respectively) methods. ANOVA indicated no overall difference for tasks 1 and 2 across the orderings (p = 0.36 and 0.99, respectively). However, by attempt 3 the time required to complete the skill tests decreased significantly for all 3 trainers (each p <0.01). CONCLUSIONS: Our homemade webcam system is comparable in function to the more elaborate video trainer but superior to the dual mirror trainer. For novice laparoscopists we believe that the webcam system is an inexpensive and effective laparoscopic training device. Furthermore, the webcam system also allows instant recording and review of techniques.

Spontaneous, unremitting gross hematuria occurring one week after laparoscopic donor nephrectomy.

Complications associated with the ureteral stump after nephrectomies rarely occur, especially after donor nephrectomies. The potential for the slippage of clips is a well-known event associated with vascular ligations. We report on the first case of clip slippage from the ureter and describe diagnosis and management of the most extreme of morbid presentations.

Spontaneous, unriitting gross hematuria occurring one week after laparoscopic donor nephrectomy

Complications associated with the ureteral stump after nephrectomies rarely occur, especially after donor nephrectomies. The potential for the slippage of clips is a well-known event associated with vascular ligations. We report on the first case of clip slippage from the ureter and describe diagnosis and managient of the most extrie of morbid presentations.

Impact of prior biopsy scheme on pathologic features of cancers detected on repeat biopsies.

The object of our study was to characterize the biopsy features of cancers detected in a repeat biopsy population stratified on the basis of the type of prior negative biopsy. We studied 218 patients with a prior negative biopsy who underwent a 10-core extended systematic biopsy scheme, and a subset (n = 139) underwent additional 6 anteriorly directed biopsies. Clinicopathologic features of patients with cancer on the biopsy were compared as a function of type of prior negative biopsy. Overall and unique cancer detection rates were calculated for each of the biopsy sites. Cancer detection rates tended to be higher in patients who had undergone a prior sextant biopsy compared to a prior extended biopsy scheme (39% vs. 28%). Trends towards more positive cores and greater total core length of cancer involvement were seen in patients who had undergone a prior negative sextant biopsy. Apical and laterally directed biopsies had higher overall and unique cancer detection rates in patients who had undergone a prior negative sextant biopsy. Anteriorly directed biopsies had a low unique cancer detection rate in all patients. We conclude that in patients undergoing repeat biopsy, the detection rate is affected by the extent of the prior biopsy. Clinicopathologic features of cancers detected on repeat biopsy tend to be worse in patients who have undergone a prior negative sextant biopsy compared to a negative prior extended biopsy.

Gene expression patterns in human embryonic stem cells and human pluripotent germ cell tumors.

Remarkably little is known about the transcriptional profiles of human embryonic stem (ES) cells or the molecular mechanisms that underlie their pluripotency. To identify commonalties among the transcriptional profiles of different human pluripotent cells and to search for clues into the genesis of human germ cell tumors, we compared the expression profiles of human ES cell lines, human germ cell tumor cell lines and tumor samples, somatic cell lines, and testicular tissue samples by using cDNA microarray analysis. Hierarchical cluster analysis of gene expression profiles showed that the five independent human ES cell lines clustered tightly together, reflecting highly similar expression profiles. The gene expression patterns of human ES cell lines showed many similarities with the human embryonal carcinoma cell samples and more distantly with the seminoma samples. We identified 895 genes that were expressed at significantly greater levels in human ES and embryonal carcinoma cell lines than in control samples. These genes are candidates for involvement in the maintenance of a pluripotent, undifferentiated phenotype.

Use of extended systematic sampling in patients with a prior negative prostate needle biopsy.

PURPOSE: We examine the potential impact of extended systematic biopsy schemes in patients with a prior negative prostate biopsy. MATERIALS AND METHODS: Between January 1999 and March 2001, 185 patients with a prior negative prostate needle biopsy underwent repeat biopsy. Systematic 10 core biopsies (sextant, lateral mid gland and lateral base) were performed in all patients. A subset of 111 patients underwent 6 additional biopsies directed anteriorly. All biopsy results were reviewed by a single pathologist. The overall and unique cancer detection rates were calculated for each biopsy site. McNemar's test was then used to compare the yield of various simulated biopsy schemes to define the optimal biopsy regimen. RESULTS: Overall, 67 of 185 patients (36%) were found to have cancer on repeat biopsy. The highest detection rate was found for the apex, lateral base and lateral mid sites. The mid lobar base site consistently yielded the lowest detection rate. These results were mirrored in the unique cancer detection rate calculations. The traditional sextant scheme detected only 73% of tumors. Using a lateral sextant scheme (apex, lateral mid gland and lateral base), the detection rate increased to 85% (p = 0.15). An 8 core biopsy scheme (apex, mid gland, lateral mid gland and lateral base) increased the detection rate to 95%. However, there was no significant increase in cancer detection rate when the 8 core scheme was compared to the 10 core scheme. The 6 anteriorly directed biopsies uniquely detected only 2 cancers. CONCLUSIONS: We recommend that patients with a prior negative prostate biopsy who are undergoing repeat biopsy receive at least an 8 core biopsy scheme weighted toward the lateral aspect of the prostate.