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Biomedical subjects

L R Kavoussi

Publications and source records attributed to L R Kavoussi.

At least 19 recordsLinked to original sources
PubMed2004

Renal transplantation with iliac vein transposition.

UNLABELLED: We evaluated a technique for implantation of right kidneys with short renal veins without the need for venous reconstruction. METHOD: The technique of iliac vein transposition was performed in six recipients who received right kidneys with short renal veins. Two cases were living related donors, two were living unrelated, one was an autotransplant, and one was a cadaver kidney recipient. The common and external iliac veins and arteries of the recipient were thoroughly mobilized, allowing for the lateral transposition of the external iliac vein with respect to the external iliac artery. The renal vessels were subsequently implanted in an end to side fashion onto the corresponding transposed external iliac vessels. After implantation, the iliac vein remained lateral with respect to the iliac artery. CONCLUSIONS: The technique described allows for the implantation of right kidneys without the need for venous reconstruction. Such an approach is especially useful in cases of grafts with short veins.

Adult↗
PubMed2004

Tumor seeding in urological laparoscopy: an international survey.

PURPOSE: During the last 10 years laparoscopy has been applied to treat most urological pathology including malignancies. There has been concern regarding peritoneal dissemination and port site metastases. We undertook a survey to assess the incidence of this occurrence. MATERIALS AND METHODS: A total of 50 international urology departments with experts in laparoscopic urological surgery were contacted for this study. Each site was asked to complete a 2-page survey regarding the volume of laparoscopic urological procedures and port site recurrences. RESULTS: Nineteen sites elected to participate. A total of 18750 laparoscopic procedures were performed, of which 10912 were for cancer. These included 2604 radical nephrectomies, 559 nephroureterectomies, 555 partial nephrectomies, 27 segmental ureterectomies, 3665 radical prostatectomies, 1869 pelvic lymph node dissections, 479 retroperitoneal lymph node dissections, 336 adrenalectomies and 108 procedures listed as other. Tumor seeding was reported in 13 cases (0.1%), including 3 nephroureterectomies for transitional cell carcinoma, 4 nephrectomies (incidental transitional cell carcinoma), 4 adrenalectomies for metastases, 1 retroperitoneal lymph node dissection for testicular cancer and 1 pelvic lymph node dissection for cancer of the penis. Port seeding occurred in 10 cases (0.09%) and peritoneal spread in 3 cases (0.03%). CONCLUSIONS: The incidence of tumor seeding after laparoscopic oncological surgery is rare and does not appear greater than what has been historically reported for open surgery. Tumor seeding seems to be most commonly related to the removal of high grade tumors and deviation from oncological surgical principles.

Follow-Up Studies↗
PubMed2003

Laparoscopic distal pancreatectomy for metastatic renal cell carcinoma.

A 64-year-old man with a remote history of left radical nephrectomy presented with a recurrent mass in the renal bed. Computed tomography findings suggested a mass in the bed of the psoas. On laparoscopic exploration, he had metastasis to the tail of the pancreas. We describe our surgical management and the patient's postoperative course.

Carcinoma, Renal Cell↗
PubMed2003

Laparoscopic renal biopsy: a 9-year experience.

OBJECTIVES: To present our experience and outcome of consecutive laparoscopic renal biopsy over a 9-year period, as renal biopsy remains an important diagnostic procedure for evaluating proteinuria, haematuria and renal failure, but when percutaneous biopsy is contraindicated, a laparoscopic biopsy is an attractive option because it is minimally invasive. PATIENTS AND METHODS: Seventy-four patients (29 male, 45 female, mean age 45 years, range 3-79) had a laparoscopic renal biopsy taken for various indications, e.g. morbid obesity, solitary kidney, coagulopathy, failed percutaneous biopsy, high location of the kidney and poor visualization with ultrasonography. The kidney was approached via a laparoscopic retroperitoneal route using a two-port technique, with the patient in the flank position. After identifying the kidney, one to five cortical biopsies were obtained with cup-biopsy forceps. RESULTS: Adequate tissue was obtained in 96% of the patients; the mean (range) operative duration was 123 (9-261) min and the estimated blood loss 67 (5-2000) mL. Forty-three patients were discharged within 24 h. Complications occurred in 10 patients, with significant bleeding in three. One patient died after surgery, secondary to a perforated peptic ulcer while on high-dose steroid therapy. CONCLUSION: Laparoscopic renal biopsy is a safe and effective alternative to open renal biopsy for patients in whom percutaneous biopsy is not feasible. It offers the advantage of obtaining cortical biopsies and achieving haemostasis under direct vision. Adequate renal tissue is obtained in most cases. Recovery and convalescence are short for most patients.

Adolescent↗
PubMed2001

Interaortocaval renal artery dissection for right laparoscopic donor nephrectomy.

Laparoscopic donor nephrectomy is gaining increasing popularity because the procedure helps reduce disincentives to live kidney donation and has increased the live kidney donor pool. The left kidney of the donor is the preferred allograft because the right renal vein is shorter. Similarly, the right renal artery might be foreshortened because it hides behind the inferior vena cava during laparoscopic transperitoneal dissection. There are instances, however, in which it is not practical to take the left kidney due to vascular anomalies or asymmetric function. We describe a novel technique for obtaining greater renal arterial length utilizing laparoscopic interaortocaval dissection.

Aorta↗
PubMed2001

Should the indications for laparascopic live donor nephrectomy of the right kidney be the same as for the open procedure? Anomalous left renal vasculature is not a contraindiction to laparoscopic left donor nephrectomy.

BACKGROUND: The left kidney is preferred for live donation. In open live donor nephrectomy, the right kidney is selected if the left kidney has multiple renal arteries or anomalous venous drainage. With laparoscopic live donor nephrectomy (LLDN), there is reluctance to procure the right kidney because of the more difficult exposure and further shortening of the right renal vein (RRV) after a stapled transection. An experience with LLDN is reviewed to determine whether the right kidney should be procured laparoscopically. METHODS: From February 1995 to November 1999, 227 patients underwent live donor renal transplants with allografts procured by LLDN. The results of these transplants were analyzed. RESULTS: Of the 227 kidneys transplanted, 17 (7.5%) were right kidneys. In the early experience, three (37.5%) of the eight right renal allografts developed venous thrombosis, two of which had duplicated RRV. Based on these initially unacceptable results, donor evaluation and LLDN techniques were modified. Spiral computerized tomography (CT) replaced conventional angiography to define better the venous anatomy. LLDN was modified in one of three ways: (1) changing the stapler port placement such that the RRV was transected in a plane parallel to the inferior vena cava, (2) relocation of the incision for open division of RRV, or (3) lengthening of the donor RRV with a panel graft constructed of recipient greater saphenous vein. Finally, the recipient operation enjoined complete mobilization of the left iliac vein with transposition lateral to the iliac artery. With these modifications, there were no vascular complications with the subsequent nine right renal allografts (P<0.05). Of the left kidneys transplanted, 31 had multiple renal arteries, 14 had retroaortic or circumaortic veins, 4 had both multiple arteries and venous anomalies, and 1 had a duplicated IVC draining the left renal vein. There were no vascular complications with left renal allografts that had multiple arteries or venous anomalies. CONCLUSIONS: LLDN of the left kidney is technically easier. Left kidneys with multiple arteries or anomalous venous drainage are not problematic. The right kidney can be procured with LLDN; however, a rational approach to preoperative angiographic imaging, donor operation, and recipient operation is crucial.

Blood Vessels↗
PubMed2001

System for robotically assisted percutaneous procedures with computed tomography guidance.

We present the prototype of an image-guided robotic system for accurate and consistent placement of percutaneous needles in soft-tissue targets under CT guidance inside the gantry of a CT scanner. The couch-mounted system consists of a seven-degrees-of-freedom passive mounting arm, a remote center-of-motion robot, and a motorized needle-insertion device. Single-image-based coregistration of the robot and image space is achieved by stereotactic localization using a miniature version of the BRW head frame built into the radiolucent needle driver. The surgeon plans and controls the intervention in the scanner room on a desktop computer that receives DICOM images from the scanner. The system does not need calibration, employs pure image-based registration, and does not utilize any vendor-specific hardware or software features. In the open air, where there is no needle-tissue interaction, we systematically achieved an accuracy better than 1 mm in hitting targets at 5-8 cm from the fulcrum point. In the phantom, the orientation accuracy was 0.6 degrees, and the distance between the needle tip and the target was 1.04 mm. Experiments indicated that this robotic system is suitable for a variety of percutaneous clinical applications.

Biopsy, Needle↗
PubMed2001

Laparoscopic radical nephrectomy: cancer control for renal cell carcinoma.

PURPOSE: We evaluated the clinical efficacy of laparoscopic versus open radical nephrectomy in patients with clinically localized renal cell carcinoma. MATERIALS AND METHODS: Between 1991 and 1999, 67 laparoscopic radical nephrectomies were performed for clinically localized, stages cT1/2 NXMX, pathologically confirmed renal cell carcinoma. During this period 54 patients who underwent open radical nephrectomy with pathologically confirmed stages pT1/2 NXMX disease were also identified. Medical and operative records were retrospectively reviewed and telephone followup was done to assess patient status. RESULTS: In the laparoscopic and open groups average tumor size was 5.1 (range 1 to 13) and 5.4 cm. (range 0.2 to 18), respectively, which was not statistically significant. No patient had laparoscopic port site, wound or renal fossa tumor recurrence in either group. All patients were followed at least 12 months. In the laparoscopic group 2 cancer specific deaths occurred at a mean followup of 35.6 months. In the open group there were 2 cancer specific deaths and 3 cases of disease progression at a mean followup of 44 months. Kaplan-Meier disease-free survival and actuarial survival analysis revealed no significant differences in the laparoscopic and open radical nephrectomy groups. Also, no differences were noted in the complication rate. CONCLUSIONS: Laparoscopic radical nephrectomy is an effective alternative for localized renal cell carcinoma when the principles of surgical oncology are maintained. Initial data show shorter patient hospitalization and effective cancer control with no significant difference in survival compared with open radical nephrectomy.

Adult↗
PubMed2001

Laparoscopic nephroureterectomy for the treatment of transitional cell carcinoma of the upper urinary tract.

OBJECTIVES: To establish the safety and efficacy of laparoscopic and laparoscopic-assisted nephroureterectomy. METHODS: Since 1993, 25 patients with a minimum of 12 months of follow-up underwent nephroureterectomy using a total laparoscopic or laparoscopic-assisted technique. Four patients had specimen morcellation for tissue removal. All patients had regular follow-up with physical examinations, interval cystoscopy, and radiographs, depending on the metastatic potential of the tumor. Retrospective chart review was performed and assessed for operative time, blood loss, tumor pathologic stage, complications, and outcome. One patient was excluded because of an open conversion due to multiple previous abdominal surgeries and failure to progress. RESULTS: The mean operating time was 329 minutes but decreased with experience. The median hospital stay was 4 days. Tumor stage was directly related to tumor grade. Associated bladder tumors (prior history or recurrent tumors) occurred in 50% of the patients. Ipsilateral ureteral stump site recurrence occurred in 1 patient. Although no port site seeding occurred, 1 patient, whose tumor was discovered histologically after laparoscopic pyeloplasty for presumed benign disease, developed recurrence in the renal fossa and metastatic disease. Two patients developed liver metastasis. CONCLUSIONS: Total laparoscopic and laparoscopic-assisted nephroureterectomy are acceptable alternatives to open surgery in the treatment of transitional cell carcinoma of the upper urinary tract. Tumor morcellation did not appear to adversely affect patient outcome. As with open nephroureterectomy, tumor grade is the most important prognostic indicator of local, bladder, and metastatic recurrence. No port site seeding was observed in either the total laparoscopic or laparoscopic-assisted groups.

Adolescent↗
PubMed2001

Hemostatic laparoscopic partial nephrectomy: initial experience with the radiofrequency coagulation-assisted technique.

OBJECTIVES: The techniques for hemostasis after renal tumor excision have limited the widespread application of laparoscopic partial nephrectomy (LPN). To improve hemostasis and aid visualization, we report our experience with a novel radiofrequency coagulation (RFC) technique for LPN. METHODS: Ten patients underwent RFC-assisted LPN. The demographic and perioperative data were tabulated. Patients were positioned as for laparoscopic nephrectomy, and laparoscopic ports were placed. The kidney within Gerota's fascia was mobilized, and the fat overlying the tumor was carefully removed for pathologic evaluation. Under laparoscopic guidance, a radiofrequency probe was percutaneously inserted into the lesion and deployed to coagulate the lesion and a margin of normal parenchyma. Laparoscopic scissors were used to excise the lesion; additional hemostatic maneuvers were used selectively. RESULTS: The mean renal tumor size was 2.1 cm (range 1.0 to 3.2). The median operative time was 170 minutes and the median blood loss was 125 mL. The RFC technique resulted in complete tissue coagulation within the treated volume, thereby facilitating intraoperative visualization, minimizing blood loss, and permitting rapid and controlled tumor resection. The renal architecture was preserved, allowing accurate diagnosis of renal cell carcinoma and angiomyolipoma in 9 and 1 cases, respectively. No perioperative complications occurred. CONCLUSIONS: The use of RFC is an effective method to facilitate LPN of both exophytic and endophytic masses. By coagulating a margin of normal parenchyma, the technique minimizes blood loss and improves visualization during LPN. We anticipate this technique will broaden the clinical application for LPN.

Adult↗
PubMed2001

Laparoscopic ablation of symptomatic parenchymal and peripelvic renal cysts.

OBJECTIVES: To assess the safety and efficacy of laparoscopic ablation of symptomatic renal cysts as minimally invasive therapeutic techniques have largely supplanted open surgical intervention for the treatment of symptomatic renal cysts. METHODS: The records of 32 consecutive adult patients who underwent laparoscopic ablation of renal cysts (11 peripelvic, 21 parenchymal) were retrospectively reviewed. All patients were symptomatic at presentation; 26 had a single cyst, 5 had two cysts, and 1 had four cysts. RESULTS: Twenty patients underwent a transperitoneal laparoscopic approach, and 12 patients underwent a retroperitoneal laparoscopic approach. An average of 3.2 ports were used for each procedure, and no open conversions or transfusions were necessary. When comparing patients with parenchymal and peripelvic cysts, statistically significant differences were noted in the mean operative time (164 versus 233 minutes, respectively; P = 0.003) and mean operative blood loss (98 versus 182 mL, respectively; P = 0.04). Four patients (13%) had complications (one major and three minor), including a persistent ureteral stricture. One patient with negative preoperative aspiration cytology and negative intraoperative frozen section analysis was later found to have malignancy within the cyst wall, necessitating radical nephrectomy and trocar site excision. One patient (3%) developed a recurrence. CONCLUSIONS: Laparoscopic ablation of symptomatic renal cysts is a safe and efficacious procedure. We report an overall complication rate of 13% and a recurrence rate of 3% with a mean follow-up of 18.1 months (median 10.0).

Adult↗
PubMed2001

Primary localized amyloidosis of the ureter.

Primary amyloidosis is a rare condition that can involve the urinary tract. These lesions can occur anywhere in the collecting system and are often mistaken clinically for malignancies. We report a case of localized ureteral amyloidosis. Our treatment consisted of a conservative approach with local resection.

Aged↗
PubMed2001

Prognostic assessment of nonmetastatic renal cell carcinoma: a clinically based model.

OBJECTIVES: Determining the recurrence risk in patients treated for renal cell carcinoma (RCC) is important for providing prognostic information and planning potential surveillance strategies. The pathologic stage has been the most widely used single prognostic variable. However, with minimally invasive treatment modalities, the pathologic stage may not be readily available. We developed a biostatistical prognostic model for postoperative RCC that is independent of the pathologic stage. METHODS: The records of 296 patients who underwent open nephrectomy for RCC at Johns Hopkins Hospital between 1990 and 1999 were reviewed. Cox proportional hazards regression analysis was used to generate a prognostic model. RESULTS: The recurrence risk (R(rec)) was determined from this model: R(rec)=1.55 x presentation (0-1)+0.19 x clinical size (in centimeters). Using this equation, 79% of patients were identified as low risk compared with 45% of patients considered low risk by pathologic stage (pT1). Moreover, the separation between the high and low-risk survival curves increased. CONCLUSIONS: This model is the first to our knowledge that uses purely clinical variables to assess the postoperative prognosis in patients with RCC. These results, although not validated, provide substantial evidence that preoperative clinical variables may be used instead of the pathologic stage to determine the risk of recurrence. Uncoupling the reliance on pathologic stage for prognostic information removes a potential barrier to novel minimally invasive treatments for renal malignancy and provides a standard to which observation protocols can be compared. In the future, this model may facilitate selection of appropriate patients for less toxic adjuvant or neoadjuvant therapies.

Aged↗