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George K Chow

Publications and source records attributed to George K Chow.

16 recordsLinked to original sources
PubMed2006

Current status of robotics in female urology and gynecology.

Currently, there has been limited reporting and research in the female urology and gynecological literature concerning the use of robotics. To date, robotics have been utilized only for the treatment of three benign gynecologic conditions: benign hysterectomy; repair of vesicovaginal fistula; and sacrocolpopexy which is a treatment for posthysterectomy vaginal vault prolapse. We describe a novel minimally invasive technique of vaginal vault prolapse repair and present our initial experience. The surgical technique involves placement of five laparoscopic ports: three for the daVinci robot and two for the assistant. A polypropylene mesh is then attached to the sacral promontory and to the vaginal apex using Gortex sutures. Thirty-one patients underwent a robotic-assisted laparoscopic sacrocolpopexy at our institution in the past 24 months for severe symptomatic vaginal vault prolapse. Complications were limited to mild port site infections in two patients, which resolved with oral antibiotic therapy. While our early experience utilizing robotic repairs in female urology and gynecology is encouraging, long-term data are needed to confirm these findings and establish longevity of the repair.

Female↗
PubMed2006

Long-term results of robotic assisted laparoscopic sacrocolpopexy for the treatment of high grade vaginal vault prolapse.

PURPOSE: Transabdominal sacrocolpopexy is a definitive treatment option for vaginal vault prolapse with durable success rates. However, it is associated with increased morbidity compared with vaginal repairs. We describe a minimally invasive technique of vaginal vault prolapse repair and present our experience with a minimum of 1 year followup. MATERIALS AND METHODS: The surgical technique involves 5 laparoscopic ports: 3 for the da Vinci robot and 2 for the assistant. A polypropylene mesh is attached to the sacral promontory and vaginal apex using polytetrafluoroethylene sutures. The mesh material is then covered by peritoneum. Patient analysis focused on complications, urinary continence, patient satisfaction and morbidity with a minimum of 12 months followup. RESULTS: A total of 30 patients with post-hysterectomy vaginal vault prolapse underwent robotic assisted laparoscopic sacrocolpopexy at our institution and 21 have a minimum of 12 months followup. Mean followup was 24 months (range 12 to 36) and mean age was 67 years (range 47 to 83). Mean operative time was 3.1 hours (range 2.15 to 4.75). All but 1 patient were discharged home on postoperative day 1 and the 1 patient left on postoperative day 2. Recurrent grade 3 rectocele developed in 1 patient, 1 had recurrent vault prolapse and 2 had vaginal extrusion of mesh. All patients were satisfied with outcome. CONCLUSIONS: The robotic assisted laparoscopic sacrocolpopexy is a minimally invasive technique for vaginal vault prolapse repair, combining the advantages of open sacrocolpopexy with the decreased morbidity of laparoscopy. We found a decreased hospital stay, low complication rates and high patient satisfaction with a minimum of 1 year followup.

Aged↗
PubMed2006

Long-term success of antegrade endopyelotomy compared with pyeloplasty at a single institution.

BACKGROUND AND PURPOSE: The classic standard for surgical repair of ureteropelvic junction (UPJ) obstruction has been open pyeloplasty, with a 95% success rate. Antegrade endopyelotomy is a less-invasive option with a slightly lower success rate. However, recent data call into question the long-term durability of UPJ repair. We present the long-term success of treatment of UPJ obstruction comparing these two modalities. PATIENTS AND METHODS: We reviewed the medical records of patients undergoing percutaneous antegrade endopyelotomy or open and laparoscopic pyeloplasty for UPJ repair in our practice from 1988 to 2004. Success was defined as both radiographic and symptomatic improvement. We evaluated the impact of preoperative factors, including prior surgical repair, crossing vessels, renal function, and calculi, on success. RESULTS: The estimated 3-, 5-, and 10-year recurrence-free survival rates for the endopyelotomy group (N = 182) were 63%, 55%, and 41%, respectively, compared with 85%, 80%, and 75% for the pyeloplasty group (N = 175; P < 0.001). Of the failed endopyelotomies undergoing salvage open repair, 8 of 26 (31%) had crossing vessels. Poor renal function and previous failed pyeloplasty decreased success in the pyeloplasty group. Variation from standard cold-knife incision adversely affected endopyelotomy success. CONCLUSIONS: Long-term success rates after both endopyelotomy and pyeloplasty are worse than previously reported. Although most failures in both groups occurred within 2 years, failures continue to appear after 5 and 10 years, and patients should be followed accordingly. In view of these results of endopyelotomy, laparoscopic pyeloplasty may prove to be the preferred minimally invasive approach to repair UPJ obstruction.

Adolescent↗
PubMed2006

The evolution of ureteroscopy: a modern single-institution series.

OBJECTIVES: To evaluate a modern ureteroscopy series, including the use of new technological advances, operative procedures, and potential complications, at a single institution and to compare our current experience with our prior published series and the current literature. MATERIAL AND METHODS: We retrospectively reviewed 1000 consecutive ureteroscopies performed in 961 patients from December 1999 to February 2003 at our institution. RESULTS: Semirigid and flexible ureteroscopes were used in 60.3% and 37.0% of the cases, respectively. In 2.6% of cases, a combination of both rigid and flexible ureteroscopes was required. The most common indications for ureteroscopy were as follows: stone, 57.9%; diagnostic, 20.6%; and urothelial carcinoma, 12.6%. Of the stones treated, 31.8% were proximal or middle and 59.1% distal. The overall, proximal, and distal stone-free rates were 91.7%, 87.3%, and 94.2%, respectively. Average operative time was 81 minutes (range, 5-280 minutes). Average follow-up was 2.36 months (range, 1-24 months). The overall complication rate was 1.9% (18/961), including a 0.2% (2/961) incidence of ureteral strictures. CONCLUSION: Current practice trends have shifted to an increased use of flexible ureteroscopes and more frequent ureteroscopic treatment of proximal calculi. Our single treatment stone-free rates are competitive with quoted shock wave lithotripsy success. In addition, there has been a decrease in ureteroscopic-associated complications in our series, with no ureteral avulsions. The improvements in treatment success and decrease in complications may be secondary to advances in ureteroscopic technology.

Adolescent↗
PubMed2005

Three-dimensional CT virtual endoscopy in the detection of simulated tumors in a novel phantom bladder and ureter model.

BACKGROUND AND PURPOSE: Cystoscopy and ureteroscopy have limitations in the evaluation for urothelial tumors, and both are invasive. We studied the utility of three-dimensional (3D) CT virtual endoscopy in phantom models. MATERIALS AND METHODS: A phantom pelvis was constructed of Plexiglas, porcine pelvic bones, and processed animal fat and scanned at various table speeds in a four detector-row CT machine for ability to detect "tumors" of Solidwater plastic polymer. Images were reconstructed at slice thicknesses of 2.5 to 5.0 mm and reconstructed in 3D for evaluation by two radiologists with no knowledge of the scanning parameters or tumor location. Similar studies were performed with a ureter model. RESULTS: With 5-mm slices, the sensitivity for bladder tumors ranged from 67% for 2-mm tumors to 100% for 4-mm tumors, with 12 false-positive findings. The overall sensitivity was 86% with 3.75-mm slices with one false positive, and with 2.5-mm slices, the sensitivity was 93%, again with one false positive. For the ureteral tumors, the overall sensitivities and numbers of false positives were 88.9% and eight with 5.0-mm collimation, 88.9% and four with 3.75-mm collimation, and 100% and three with 2.5-mm collimation. The effective radiation dose for all studies was equivalent to that of a standard abdomen/pelvis scan. CONCLUSIONS: Although virtual endoscopy traditionally has had difficulty detecting tumors <5 mm, the multidetector-row CT protocols used in this study could detect most lesions smaller than this. The scan also depicts the other tissues of the pelvis, which is valuable for staging. The 3D images were produced using data from the CT urogram parameters standard at our institution.

Animals↗
PubMed2005

Ureteroscopic resection of upper-tract transitional-cell carcinoma.

Technological advances have increased the applicability of endoscopic treatment for upper-tract transitional-cell carcinoma (TCC). Percutaneous and ureteroscopic tumor resection have become reasonable treatment options for patients with anatomically or functionally solitary kidneys, bilateral upper-tract tumors, significant renal insufficiency, or comorbid disease that would preclude standard open surgery. This approach also is being used increasingly on those with a normal contralateral kidney in whom nephroureterectomy and en bloc removal of the ipsilateral ureteral orifice and surrounding bladder cuff is considered the standard therapy. This paper reviews the current role of ureteroscopic management of upper-tract TCC.

Carcinoma, Transitional Cell↗
PubMed2005

Obesity in living kidney donors: clinical characteristics and outcomes in the era of laparoscopic donor nephrectomy.

Acceptance of obese individuals as living kidney donors is controversial related to possible increased risk for surgical complications and concern that obesity may contribute to long-term renal disease. We retrospectively examined 553 consecutive hand-assisted laparoscopic living kidney donations between October 1, 1999 and April 1, 2003. We stratified donors into quartiles by baseline body mass index (BMI) assessing perioperative complications and 6-12 months post-donation metabolic and renal function. Compared to BMI <25 kg/m(2), high BMI donors (> or =35 kg/m(2)) had slightly longer operative times (mean increase 19 min), more overall perioperative complications (mostly minor wound complications), yet the same low rate of major surgical complications (conversion to open and re-operation) and similar length-of-stay (2.3 vs. 2.4 days). At 6-12 months after donation (mean 11 months), renal function and microalbuminuria did not differ with BMI. These results suggest that laparoscopic donor nephrectomy is generally safe in selected obese donors and does not result in a high rate of major perioperative complications. Obese donors have higher baseline cardiovascular risk and warrant risk reduction for long-term health. While early results are encouraging, we advocate careful study of obese donors and do not support their widespread use until longer follow-up is available.

Adult↗
PubMed2004

Gynecologic use of robotically assisted laparoscopy: Sacrocolpopexy for the treatment of high-grade vaginal vault prolapse.

Transabdominal sacrocolpopexy is an excellent treatment option for patients with high-grade vaginal vault prolapse, with long-term success rates ranging from 93% to 99%. However, it is associated with increased morbidity compared with vaginal repairs. In this article, we describe a novel minimally invasive technique of vaginal vault prolapse repair and present our initial experience. The surgical technique involves placement of 4 laparoscopic ports, 3 for the surgical robot and 1 for the assistant. A prolene mesh is then attached to the sacral promontory and to the vaginal apex using nonabsorbable expanded polytetrafluoroethylene sutures. At the end of the case, the mesh material is covered by the peritoneum. A total of 20 patients underwent a robot-assisted laparoscopic sacrocolpopexy at our institution in the past 18 months for severe symptomatic vaginal vault prolapse; 8 of the 20 (40%) underwent a concomitant anti-incontinence procedure. Mean follow-up was 5.1 (range, 1-12) months and mean age was 66 (range, 47-82) years. The mean total operative time was 3.2 (range, 2.25-4.75) hours. Of these patients, 1 was converted to an open procedure secondary to unfavorable anatomy. All but 1 patient, who left on postoperative day 2, were discharged from the hospital after an overnight stay. Complications were limited to mild port-site infections in 2 patients, which resolved with oral antibiotic therapy. Recurrent grade 3 rectocele developed in 1 patient, but there was no evidence of cystocele or enterocele. Significant incontinence (>1 pad/day) was present in 2 patients. All 18 patients reported being satisfied with the outcome of their surgery and all 10 would recommend it to a friend. This novel technique for vaginal vault prolapse repair combines the advantages of open sacrocolpopexy with the decreased morbidity and improved cosmesis of laparoscopic surgery. It is associated with decreased hospital stay, low complication and conversion rates, and high rates of patient satisfaction. Although our early experience is encouraging, long-term data are needed to confirm these findings and establish longevity of the repair.

Aged↗
PubMed2004

Robotic-assisted laparoscopic sacrocolpopexy for treatment of vaginal vault prolapse.

INTRODUCTION: To describe and demonstrate the use and benefit of robotic-assisted laparoscopic sacrocolpopexy in the treatment of posthysterectomy vaginal vault prolapse. TECHNICAL CONSIDERATIONS: The procedure combines the use of standard laparoscopy with the daVinci robotic system. The patient is placed in the dorsal lithotomy position. One camera port, two robotic ports, and two standard laparoscopic ports are placed transperitoneally. Standard laparoscopic dissection, in combination with an intravaginal retractor, is used for initial anterior and posterior vaginal mobilization and exposure of the sacral promontory. The daVinci robot is then docked and used to suture a silicone Y-shaped graft from the vagina to the sacral promontory. Culdoplasty, with plication of the uterosacral ligaments, is then performed, with the final step, retroperitonealization of the graft. CONCLUSIONS: A total of 5 women have undergone this procedure, 3 with concomitant pubovaginal sling placement. All 5 women were discharged after 24 hours. No complications from the sacrocolpopexy were reported; however, 1 patient experienced transient vaginal bleeding related to the pubovaginal portion of the case. No recurrent anterior, posterior, or apical prolapse has occurred at mean of 4 months of follow-up. Using a robotic system for laparoscopic sacrocolpopexy facilitated precise intracorporeal suture placement so that the procedure could be done in a fashion similar to that of the open method. Robotic-assisted laparoscopic sacrocolpopexy may provide the same long-term durability of open sacrocolpopexy with the benefit of a minimally invasive approach.

Female↗
PubMed2004

Robotic-assisted laparoscopic partial nephrectomy: technique and initial clinical experience with DaVinci robotic system.

OBJECTIVES: To develop and assess the feasibility of laparoscopic partial nephrectomy performed using the daVinci robotic system. METHODS: Between November 2002 and August 2003, 13 patients with solid or suspicious cystic renal masses underwent robotic-assisted laparoscopic partial nephrectomy. In 8 cases, an intra-arterial catheter was inserted for renal cooling before occlusion of the renal artery. The remaining 5 patients underwent partial nephrectomy after the renal hilum had been clamped. Tumor excision and intracorporeal suturing were performed entirely with telerobotics. The perioperative data and pathologic results were retrospectively reviewed. RESULTS: The mean lesion diameter was 3.5 cm (range 2.0 to 6.0). The mean operative time was 215 minutes (range 130 to 262), and the mean blood loss was 170 mL (range 50 to 300). The mean warm ischemia was 22 minutes (range 15 to 29), and the mean cold ischemia time was 33 minutes (range 18 to 43). The length of hospital stay averaged 4.3 days (range 2 to 7). The resected lesions included renal cell carcinoma in 10, oncocytoma in 2, and a complex renal cyst in 1. In 1 case, a positive margin occurred despite negative frozen sections; laparoscopic nephrectomy was performed and showed no residual tumor. One patient experienced postoperative ileus. At 2 to 11 months of follow-up, no recurrence had been observed. CONCLUSIONS: Robotic-assisted partial nephrectomy is feasible. Robotic partial nephrectomy can be safely performed using a transperitoneal or retroperitoneal approach. A second scrubbed assistant is mandatory to provide assistance using conventional laparoscopic instruments with this technique.

Adenoma, Oxyphilic↗
PubMed2004

Vena caval transection during retroperitoneoscopic nephrectomy: report of the complication and review of the literature.

PURPOSE: Major vascular injuries are uncommon but serious complications of laparoscopic surgery. Early recognition and conversion to an open procedure may be required to avoid further complications. We report 2 cases in which the vena cava was transected during retroperitoneoscopic nephrectomy, and review the literature. MATERIALS AND METHODS: All urological laparoscopic cases from 1993 to 2002 at 2 institutions were reviewed to identify major vessel transection. Two cases of inadvertent transection of the vena cava were identified. Medical records were reviewed for clinical and pathological information to identify factors leading to this complication. A MEDLINE search was performed to identify similar reports in the literature. RESULTS: Two patients at 2 institutions were identified with vena caval transection during retroperitoneoscopic nephrectomy. In both cases the vena cava was misidentified as a renal vein. The injury was recognized immediately in both cases and an open repair was performed by vascular surgery. Both patients recovered with no sequelae. In both cases a rotated camera on an angled laparoscope in addition to the relative lack of retroperitoneal landmarks may have contributed to a loss of orientation within the operative field. A similar report of an aortic transection was also found in the literature. CONCLUSIONS: Disorientation of the operating surgeon within the surgical field secondary to rotation of the camera lens and lack of retroperitoneal landmarks may contribute to vena caval transection during retroperitoneoscopic nephrectomy. This injury has not been found in transperitoneal nephrectomy, likely because more intra-abdominal landmarks exist, aiding in maintenance of orientation. Prompt intraoperative recognition and repair of the transection results in a favorable outcome.

Adult↗
PubMed2004

Hand-assisted laparoscopic donor nephrectomy for pediatric kidney allograft recipients.

Laparoscopic donor nephrectomy (LDN) is the method of choice for procuring kidneys from living donors at many transplant centers. The aim of this study was to assess the feasibility as well as outcome of LDN in pediatric recipients. Twenty-two pediatric patients, 18-yr old or younger received kidneys procured by a hand-assisted LDN technique. The mean operative time was no different (p = 0.9) and the mean length of stay was more than 1 day shorter in the LDN group (p = 0.0001) compared with the 13 pediatric patients who received kidneys by standard open nephrectomy. Body mass index (BMI), number of donor kidney vessels, or laterality of the kidney did not impact the donor operation or outcome. Actuarial 1-yr patient survival was 100% and allograft survival was 95%, which are equivalent to registry data. There were no donor mortalities and there were five morbidities. None required hospitalization. There were no conversions from LDN to open nephrectomy. One kidney was lost because of overwhelming infection necessitating withdrawal of immunosuppression. In conclusion, hand-assisted LDN is a safe method of procuring kidneys from potential donors with no significant negative outcomes to the pediatric recipients.

Adolescent↗
PubMed2004

Minimally invasive radical prostatectomy.

The development of advanced laparoscopic techniques and robot-assisted technology has resulted in several new surgical approaches for treating organ-confined prostate cancer. Outcomes with these new or minimally Invasive techniques should be assessed carefully to ensure that they are similar to or surpass patients' oncologic and functional outcomes after open radical prostatectomy. This article reviews the current published experience with minimally Invasive approaches to increase awareness about viability. Several of the larger series of patients who have undergone laparoscopic (transperitoneal and extraperitoneal) or robot-assisted laparoscopic radical prostatectomies are discussed and evaluated critically. Comparisons to published data on open radical prostatectomy are included for completeness. The different minimally invasive techniques are described and contrasted in regard to prostate-specific antigen progression-free survival, surgical margin status, blood loss, transfusion rates, postoperative pain, length of hospitalization, duration of urinary catheterization, potency, continence, and complications. The relative costs of each method are provided. The coexistence of multiple surgical approaches should and can challenge surgeons who perform open and minimally invasive procedures to strive for a new standard of care above and beyond what is accepted today to minimize patient morbidity while maximizing functional and oncologic outcomes.

Adult↗
PubMed2003

Ureteroscopy: effect of technology and technique on clinical practice.

PURPOSE: Technical advances in ureteroscopy allow for more aggressive management of upper tract pathology. We evaluate to what extent clinical practice and treatment efficacy have been impacted by improvements in technology and technique. MATERIALS AND METHODS: In 1998, 176 consecutive patients underwent 182 ureteroscopic procedures at our institution. Retrospective chart review was performed. Factors such as clinical indication, pathology location, type of ureteroscope, procedure duration, procedure success, complication rate and length of stay were evaluated. Data from the 1998 cohort were compared to those obtained from a cohort of patients from 1992. Statistical analysis was performed using chi-square test. RESULTS: Overall stone extraction rate was 94.4% (1992) vs 88.5% (1998) (p = 0.05). Proximal stones were treated in 13.5% (1998) vs 28.3% (1998) of cases. Distal stone extraction rate was 97.2% (1992) vs 95.1% (1998) (p = 0.43) and proximal stone extraction rate was 76.5% (1992) vs 71.9% (1998) (p = 0.73). Diagnostic inspection success rate was 98.3% (1992) vs 98.3% (1998). Use of flexible ureteroscopy was 11.5% (1992) vs 29.4% (1998). Complication rate was 12% (1992) vs 10.2% (1998) (p = 0.76). Of the cases 76.1% were outpatient in 1998 vs only 50% in 1992. CONCLUSIONS: Recent advances in ureteroscopic technology permit more aggressive instrumentation of the upper tract as reflected in higher use of flexible ureteroscopy and more frequent attempts to manage proximal ureteral calculi. These advances have not translated into better efficacy of calculus treatment. Furthermore, our data reflect a nationwide trend toward outpatient treatment.

Adolescent↗
PubMed2002

The effect of previous abdominal surgery on urological laparoscopy.

PURPOSE: Abdominal surgery causes adhesions that may render subsequent laparoscopic access and dissection problematic. We determined the effect of previous surgery on the operative outcome in a large series of patients undergoing urological laparoscopy. MATERIALS AND METHODS: The records of 700 consecutive laparoscopic procedures performed at a single institution from 1995 to 2001 were reviewed. Patient gender, American Society of Anesthesiologists (ASA) patient classification, surgical history, operative time, estimated blood loss, transfusion rate, rate of conversion to an open procedure, complication rate and hospital stay were assessed in each patient. Patients were categorized by anatomical site of previous surgeries and the type of laparoscopic procedure performed. Statistical analysis was performed with 1-way ANOVA, and the chi-square, Fisher exact and Kruskal-Wallis tests. RESULTS: Of the 700 patients 366 (52%) had never undergone surgery, 105 (15%) had a history of abdominal surgery at the same anatomical region and 229 (33%) had a history of abdominal surgery at a different region. Overall previous abdominal surgery of any type was associated with female gender, higher ASA classification, increased age and an increased rate of perioperative transfusion (p = 0.0001). A history of surgery at the same site was associated with increased operative time (p = 0.03) and increased hospital stay (p = 0.02). Differences in operative blood loss (p = 0.3), and the complication (p = 0.11) and conversion (p = 0.08) rates in patients with and without a history of surgery did not attain significance. Outcomes analysis of individual types of surgery showed similar results except for renal biopsy. In these cases previous surgery was not associated with increased age, ASA score or transfusion rate. CONCLUSIONS: Of all patients presenting to a single center for urological laparoscopy 48% had a history of abdominal surgery. Overall compared with patients with no history of surgery those with such a history tended to be older, predominantly female and at significantly higher operative risk. Patients with a history of surgery who underwent nephrectomy or pyeloplasty were also more likely to have received blood transfusion perioperatively, which was probably related to their increased age and higher degree of medical co-morbidity. There were no significant differences in operative blood loss, rate of conversion to open procedure or rate of operative complications. Therefore, previous abdominal surgery does not appear to affect adversely the performance of subsequent urological laparoscopy.

Abdomen↗