Patrick W. Mufarrij

Robotic Dismembered Pyeloplasty: A 6-Year, Multi-Institutional Experience

PURPOSE The introduction of the da Vinci Surgical System to perform complex reconstructive procedures, such as repair of ureteropelvic junction obstruction, has helped to overcome some of the technical challenges associated with laparoscopy. We review our large multi-institutional experience with long-term followup of robotic dismembered pyeloplasty. MATERIALS AND METHODS A total of 140 patients from 3 university medical centers underwent robotic dismembered pyeloplasty. An institutional review board approved retrospective chart review was performed to collect demographic, preoperative, operative and postoperative data. Patients were analyzed as an entire cohort and then divided into various subgroups. RESULTS Of the cases 117 (84.6%) were primary repairs and 23 (16.4%) were secondary repairs. There were 13 (9.3%) patients who underwent concomitant stone extraction and 5 (3.6%) procedures were performed on patients with solitary kidneys. A crossing vessel was found in 77 (55%) patients. Mean operative time was 217 minutes (range 80 to 510), estimated blood loss was 59.4 ml (range 10 to 600), mean length of hospital stay 2.1 days (range 0.75 to 7) and mean followup was 29 months (range 3 to 63). Radiographic resolution of obstruction on first postoperative diuretic renal scan or excretory urogram was noted in 134 patients (95.7%). There was a 7.1% major complication rate and a 2.9% minor complication rate. No statistically significant differences were found in any parameters among patients from the various cohorts. CONCLUSIONS To our knowledge this review represents the largest multi-institutional experience of robotic dismembered pyeloplasty with long-term followup. Robotic pyeloplasty appears to be safe, durable and efficacious for primary and secondary ureteropelvic junction obstruction with or without concomitant stone extraction, and for patients with a solitary kidney.

Does Nephrometry Scoring of Renal Tumors Predict Outcomes in Patients Selected for Robot-Assisted Partial Nephrectomy?

BACKGROUND AND PURPOSE Robot-assisted partial nephrectomy has emerged as a viable surgical treatment for patients with certain renal tumors. We hypothesized that extirpation of more complex tumors, as graded with the nephrometry score, would result in worse operative and postoperative outcomes when compared with tumors with lower nephrometry scores. We report whether nephrometry-graded tumor complexity impacted operative or postoperative outcomes. PATIENTS AND METHODS A single experienced surgeon at our tertiary-care institution performed more than 100 robot-assisted partial nephrectomies. Istitutional Review Board-approved data collection was available for 95 patients, and nephrometry scores were available for 92 patients. Cases were divided into tertiles, based on their nephrometry score of low, medium, or high. We compared preoperative, operative, and postoperative data to evaluate any differences between the three tertiles. Statistical analysis was performed using JMP 8 software. RESULTS There were 66, 22, and 4 patients in the low, medium, and high nephrometry score tertiles, respectively. There were no statistically significant differences between the tertiles regarding warm ischemia time, estimated blood loss, operative time, length of stay, change in glomerular filtration rate, Clavien-graded complication rates, or any other metric. Mean follow-up for each tertile was also similar. CONCLUSIONS We have routinely been using the nephrometry scoring system to anatomically describe renal masses before robot-assisted partial nephrectomy. Our findings demonstrate that nephrometry-graded tumor complexity was not related to any differences in outcomes for patients with renal tumors who were selected at our institution to undergo robot-assisted partial nephrectomy. The nephrometry system remains a reproducible standardized classification of renal tumor anatomy, but it remains to be seen if this can be used to predict surgical outcomes.

Minimally Invasive Management of Retroperitoneal Fibrosis

OBJECTIVES Ureteral obstruction is a common finding in retroperitoneal fibrosis (RPF). The management of ureteral obstruction in patients with RPF is challenging and controversial. To our knowledge we are the first to report on laparoscopic ureterolysis (LU) and robotic ureterolysis (RU) for the management of RPF to determine feasibility and success. METHODS We reviewed the charts of all patients who have undergone laparoscopic ureterolysis with or without robotic assistance at our institution. RESULTS Between 2001 and 2006, one surgical team performed laparoscopic ureterolysis with or without robotic assistance on 15 renal units in 10 patients. Mean age was 50.9 years (range, 28 to 71 years). Eight patients presented with back pain and all 15 renal units had radiographic evidence of obstruction. Five patients underwent LU, and 5 underwent RU. Mean operative times for bilateral and unilateral LU were 509.0 and 110 minutes, and the mean estimated blood loss was 362.5 and 50 mL. Mean operative times for bilateral and unilateral RU were 390 and 220.5 minutes, and the mean estimated blood loss was 25 and 35.5 mL. With a mean follow-up of 15.6 months, 90% of all patients were asymptomatic and 86.7% renal units had no signs of obstruction on imaging. CONCLUSIONS Laparoscopic ureterolysis with or without robotics may be performed with minimal perioperative morbidity and provides excellent success rates for relief of symptoms and obstruction in RPF. RU appears to have better short-term outcomes and is now our technique of choice.

Robot-assisted laparoscopic partial cystectomy and diverticulectomy: initial experience of four cases.

PURPOSE We report our initial experience with four cases of robot-assisted laparoscopic partial cystectomy and diverticulectomy performed between June 2005 and August 2007. PATIENTS AND METHODS The series consisted of three male patients and one female with a mean age of 64 years (range 36-77 years). In each case, a transperitoneal laparoscopic approach was used to mobilize the bladder. Next the bladder lesion was scored circumferentially cystoscopically with a Collings knife. The remainder of the excision and bladder reconstruction was performed with the da Vinci robot. RESULTS Mean operative time was 194 minutes with a mean blood loss of 35 mL. The urethral catheter was removed between 5 and 14 days following a normal cystogram. There were no significant complications. Postoperative hospital stay was 2 to 3 days. CONCLUSION Robot-assisted laparoscopic partial cystectomy and diverticulectomy are technically feasible and represent an alternative to open and conventional laparoscopic approaches.

Sensitivity of Human Strains of Oxalobacter formigenes to Commonly Prescribed Antibiotics

OBJECTIVE To determine the sensitivity of 4 strains of Oxalobacter formigenes (Oxf) found in humans--HC1, Va3, CC13, and OxK--to varying concentrations of commonly prescribed antibiotics. Oxf gut colonization has been associated with a decreased risk of forming recurrent calcium oxalate kidney stones. METHODS For each strain and each antibiotic concentration, 100 μL of an overnight culture and 100 μL of the appropriate antibiotic were added to a 7-mL vial of oxalate culture medium containing 20 mM oxalate. On the fourth day, vials were visually examined for growth, and a calcium oxalate precipitation test was performed to determine whether Oxf grew in the presence of the antibiotic. RESULTS All 4 Oxf strains were resistant to amoxicillin, amoxicillin/clavulanate, ceftriaxone, cephalexin, and vancomycin, and they were all sensitive to azithromycin, ciprofloxacin, clarithromycin, clindamycin, doxycycline, gentamicin, levofloxacin, metronidazole, and tetracycline. One strain, CC13, was resistant to nitrofurantoin, and the others were sensitive. Differences in minimum inhibitory concentration between strains were demonstrated. CONCLUSION Four human strains of Oxf are sensitive to a number of antibiotics commonly used in clinical practice; however, minimum inhibitory concentrations differ between strains.

Analysis of robotic-assisted laparoscopic pyleloplasty for primary versus secondary repair in 119 consecutive cases.

OBJECTIVE To analyze the outcomes of our robotic-assisted pyeloplasty series for primary ureteropelvic junction obstruction (UPJO) and compare them with our series of robotic-assisted pyeloplasty for secondary UPJO. The repair of secondary UPJO can pose additional challenges to surgeons. Robotic assistance could aid in these repairs. METHODS Using an institutional review board-approved database, we reviewed 119 consecutive patients who had undergone robotic-assisted laparoscopic pyeloplasty at our institution during an 8-year period (May 2002 to February 2010). Data were collected in a combined retrospective and prospective manner. The patients were stratified into primary repair and secondary repair for the primary analysis. The patients were also stratified into those with stones and those without stones for the secondary analysis. We compared the demographic, operative, postoperative, and radiographic outcomes. Students t test and Pearsons chi-square correlation were used for statistical analysis of continuous and categorical variables, respectively. RESULTS Of the original 119 patients, data were available for 117. Of the 117 patients, 97 had undergone primary pyeloplasty repair and 20 had undergone secondary pyleloplasty repair. Radiographic data were available for 84 patients with primary repair and 17 patients with secondary repair. The radiographic success rate was 96.1% and 94.1%, respectively. No statistically significant differences were found in the patient demographics, operative data, or postoperative or radiographic outcomes for the primary analysis. Additionally, no differences were found in the outcomes for patients with concomitant stone disease. CONCLUSION These data represent the largest single-center report of its kind. These data strongly suggest that robotic-assisted laparoscopic pyeloplasty is a safe and durable option for secondary UPJO repair.

A prospective, multi-institutional study of flexible ureteroscopy for proximal ureteral stones smaller than 2 cm

PURPOSE Flexible ureteroscopy is rapidly becoming a first line therapy for many patients with renal and ureteral stones. However, current understanding of treatment outcomes in patients with isolated proximal ureteral stones is limited. Therefore, we performed a prospective, multi-institutional study of ureteroscopic management of proximal ureteral stones smaller than 2 cm to better define clinical outcomes associated with this approach. MATERIALS AND METHODS Adult patients with proximal ureteral calculi smaller than 2 cm were prospectively identified. Patients with concomitant ipsilateral renal calculi or prior ureteral stenting were excluded from study. Flexible ureteroscopy, holmium laser lithotripsy and ureteral stent placement was performed. Ureteral access sheath use, laser settings and other details of perioperative and postoperative management were based on individual surgeon preference. Stone clearance was determined by the results of renal ultrasound and plain x-ray of the kidneys, ureters and bladder 4 to 6 weeks postoperatively. RESULTS Of 71 patients 44 (62%) were male and 27 (38%) were female. Mean age was 48.2 years. ASA(®) score was 1 in 12 cases (16%), 2 in 41 (58%), 3 in 16 (23%) and 4 in 2 (3%). Mean body mass index was 31.8 kg/m(2), mean stone size was 7.4 mm (range 5 to 15) and mean operative time was 60.3 minutes (range 15 to 148). Intraoperative complications occurred in 2 patients (2.8%), including mild ureteral trauma. Postoperative complications developed in 6 patients (8.7%), including urinary tract infection in 3, urinary retention in 2 and flash pulmonary edema in 1. The stone-free rate was 95% and for stones smaller than 1 cm it was 100%. CONCLUSIONS Flexible ureteroscopy is associated with excellent clinical outcomes and acceptable morbidity when applied to patients with proximal ureteral stones smaller than 2 cm.

Robot-Assisted Reconstructive Surgery for Ureteral Malignancy: Analysis of Efficacy and Oncologic Outcomes

BACKGROUND AND PURPOSE There have been previous reports of the use of robotic technology for the surgical treatment of ureteral neoplasms such as transitional-cell carcinoma. These have lacked long-term follow-up, been isolated cases, or focused on only the distal ureter. This investigation examines a series of mid and distal ureteral neoplasms managed with surgeon controlled robotic techniques at a tertiary care medical center. We present perioperative data and long-term follow-up, with emphasis on oncologic outcomes. PATIENTS AND METHODS This series includes six consecutive patients who have undergone robot-assisted surgical extirpation of mid and distal ureteral malignancies since 2008. Four patients underwent robot-assisted distal ureterectomy with ureteroneocystostomy, and two underwent midureter segmental excision with ureteroureterostomy. Patient demographics, intraoperative data, final pathology results, and oncologic follow-up were reviewed retrospectively. RESULTS Total mean operative time was 268.5 minutes, including the cystoscopy and change of position component of the procedure; mean estimated blood loss was 72.5 mL, and the mean length of stay was 1.8 days. All four patients who underwent distal ureterectomy also had excisions of the ipsilateral bladder cuff-three needed a psoas hitch to facilitate the ureteroneocystostomy. Final pathology results revealed four cases of transitional-cell carcinoma, one case of ureteral carcinoma in situ, and one case of non-Hodgkin diffuse-type B-cell lymphoma. The only complication was a small hydrocele in one patient. All patients underwent standard surveillance protocol, with a recurrence in the bladder developing in one patient. Ureteral obstruction did not develop in any patient postoperatively. Mean length of follow-up was 33 months. CONCLUSIONS Robot-assisted surgery is well suited for the complex reconstruction of the mid and distal ureter after excision of low-grade malignant lesions. This series demonstrates that this surgical approach offers excellent intermediate-term oncologic outcomes with preservation of ipsilateral renal function. We believe that robotic surgery may be considered as a first-line option for the minimally invasive excision and reconstruction of low-grade, localized ureteral malignancy in selected patients at centers with experienced teams.

Robotic renal and upper tract reconstruction.

Purpose of review To evaluate the current role of robotic surgery in upper urinary tract reconstruction. Recent findings Robotic techniques have been increasingly adopted by urologists for reconstruction of the upper urinary tract. The improved dexterity, visualization, and ergonomics of robotic systems have applied naturally to reconstruction and have facilitated intracorporeal suturing compared with traditional laparoscopy. In particular, robotic techniques have been used for anastamotic suturing during minimally invasive pyeloplasty. Series of robotic pyeloplasty have demonstrated comparable long-term outcomes to laparoscopy, a shorter learning curve, subjective operator benefits, and potential advantages in operative time. Other robotic reconstructive procedures of the upper tract have included ureterocalicostomy, ureteroureterostomy, ureterolysis, and ureteral reimplantation with and without psoas hitch. Summary Robotic techniques provide clear advantages for minimally invasive upper tract reconstruction, though the objective benefits need further delineation. These procedures are in their early experience, and larger series with prospective randomized comparison with the standard of care are warranted. Low volume of upper tract reconstruction in general will likely require multi-institutional study. Continued study of cost-effectiveness is necessary to define the optimal role for robotic reconstruction in both medical and economic terms.

Robotic Ureterolysis for Relief of Ureteral Obstruction from Retroperitoneal Fibrosis

OBJECTIVE To review our experience with robotic surgery for the management of retroperitoneal fibrosis (RPF) with ureteral obstruction. Ureteral obstruction is common in retroperitoneal fibrosis RPF. METHODS Since April 2006, 21 patients have presented to our institution with ureteral obstruction, apparently from RPF. All underwent robotic biopsy. If frozen pathology reveals malignancy, is equivocal, and/or the fibrotic reaction is extensive, we stent the obstructed side(s) and await final pathology. If RPF is confirmed, medical therapy is initiated to relieve obstruction; failures receive salvage ureterolysis. Lymphomas are referred to medical oncology. If frozen pathology demonstrates RPF, immediate ureterolysis is performed, if technically feasible. Ureterolysis is not performed for uninvolved contralateral systems. We reviewed data with institutional review board approval. RESULTS Of 21 patients, 3 were diagnosed with lymphoma and 18 with RPF. Seventeen patients (21 renal units) with RPF received robotic ureterolysis (11 primary, 6 salvage); the other patient died of trauma before intervention. The only perioperative complication, an enterocutaneous fistula, required bowel resection. Three patients required a secondary procedure to relieve obstruction. At a mean follow-up of 20.5 months, no renal unit has evidence of obstruction, and all patients have improved or resolved symptoms. Furthermore, none of the 13 patients who underwent a unilateral ureterolysis have had disease progression to the contralateral side. CONCLUSIONS Robotic ureterolysis can be performed with minimal morbidity and provides durable success rates for relief of symptoms and obstruction in RPF. Biopsy remains integral to ruling out lymphoma. Empiric contralateral ureterolysis may not be necessary.