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Jaime Landman

Publications and source records attributed to Jaime Landman.

At least 19 recordsLinked to original sources
PubMed2005

Complex laparoscopic partial nephrectomy for renal hilar tumors.

OBJECTIVES: To evaluate our experience with laparoscopic partial nephrectomy (LPN) for tumors located adjacent to the renal hilum. Continued advances in laparoscopic technology and technique have made LPN feasible for increasingly anatomically complex tumors. METHODS: A retrospective chart review was performed of all patients who underwent LPN at Washington University. We identified 8 patients who had undergone LPN between December 2001 and September 2004 for hilar tumors that were defined as those located within 5 mm of the renal hilar vessels. The data were retrospectively analyzed for parameters, including operative time, morbidity, and postoperative course. RESULTS: LPN was successfully completed in all 8 patients without conversion to an open or hand-assisted approach. The indication for nephron-sparing surgery was elective in 6 patients and imperative in 2. The mean operative time was 3.0 hours (range 2.5 to 3.5), and the mean estimated blood loss was 188 mL (range 30 to 700). All patients had negative margins on the final pathologic examination. No intraoperative complications occurred. Nine postoperative complications developed in 6 patients. They included hemorrhage in 1, fever in 1, ileus in 1, urinary tract infection in 1, urine leak in 4, and transient postoperative neuropathy in 1 patient. CONCLUSIONS: With adequate laparoscopic experience, LPN for hilar tumors is a reasonable surgical option. In our experience, the procedure was associated with an increased risk of urine leak. Preoperative placement of a ureteral catheter to help delineate collecting system violations and routine postoperative stenting may reduce the incidence of this complication.

Adult↗
PubMed2005

Single-setting bilateral laparoscopic renal surgery: assessment of single-stage procedure.

OBJECTIVES: To assess the safety and efficacy of single-setting bilateral laparoscopic renal procedures. The continued advancement of laparoscopic surgical technology and surgeon expertise has allowed increasingly technically challenging procedures to be completed laparoscopically. Little has been reported on patient outcome, morbidity, and mortality of bilateral laparoscopic single-stage procedures. METHODS: Between May 2000 and February 2004, 13 patients underwent synchronous bilateral renal surgery. Both retroperitoneal (n = 5) and transperitoneal (n = 8) approaches were used. The data were retrospectively analyzed for operative time, morbidity, mortality, and postoperative course. RESULTS: Bilateral laparoscopic procedures were successfully completed in 11 (85%) of 13 patients. One patient required conversion to an open procedure because of significant adhesions. Another patient with von Hippel-Lindau disease had unexpected extensive pathologic features in each kidney and was therefore treated in a staged fashion. The mean operative time was 5.5 hours (range 4.7 to 8.5). The mean estimated blood loss was 268 mL (range 50 to 950). Patients resumed oral intake and ambulated within 24 hours after surgery. The mean analgesic requirement was 40.5 mg MSO4 equivalents (range 2 to 178). The mean hospital stay was 3.1 days (range 1 to 6). Patients returned to partial activity within the first week and enjoyed full activity at 3 weeks. One intraoperative complication and five postoperative complications occurred in 5 patients. CONCLUSIONS: Our results have demonstrated that single-setting bilateral laparoscopic renal surgery is safe and can expedite resolution of urologic pathologic findings without increased morbidity. Bilateral single-setting laparoscopic surgery should only be performed if the primary procedure has been completed expeditiously and without complications.

Adolescent↗
PubMed2005

Development of exophytic tumor model for laparoscopic partial nephrectomy: technique and initial experience.

OBJECTIVES: To develop and test a porcine model to help teach the techniques needed to perform laparoscopic partial nephrectomy (LPN), which is a technically challenging procedure with necessary reconstructive skills that are difficult to transfer. METHODS: A tumor model was created by unilateral subcapsular percutaneous injection of liquid plastic (Smooth-Cast 320) in five pig kidneys. Five Washington University urologists performed LPN and assessed the efficacy of the tumor model. Subsequently, the tumor model was evaluated as a tool for teaching LPN during the Washington University Advanced Laparoscopic and Robotic Urologic Oncology Course. Twenty-eight participants performed unilateral porcine LPN with the tumor model. Questionnaires were used to assess the utility of this tumor model. RESULTS: Unilateral tumors were successfully created in five pigs and remained intact during all LPN procedures. Visually, the tumors appeared as white exophytic masses. Ultrasonography revealed a well-circumscribed, hypoechoic lesion and a mean diameter of 2.02 cm. The mean operative time was 32.4 minutes. In subsequent testing, 24 (86%) of the 28 participants returned the questionnaire, and 96% responded that the tumor model had enhanced their LPN learning experience. Seven course participants (29%) reported problems with hemostasis, ultrasonography, or laparoscopic instrumentation. Two tumor model-related complications occurred. During the initial evaluation, one pig experienced a fatal pulmonary embolism of the plastic. During the course, a second animal experienced extravasation of the solution into the renal collecting system. CONCLUSIONS: For surgical education purposes, the Smooth-Cast model is an effective surgical tool for LPN. Most of the surgeons in this evaluation believed the model enhanced their learning experience.

Animals↗
PubMed2005

Laparoscopic renal parenchymal hypothermia with novel ice-slush deployment mechanism.

OBJECTIVES: To report the development of a novel, simple-to-use method for laparoscopic deployment of fine-quality saline ice slush by way of a 10-mm end-effector for laparoscopic parenchymal hypothermia. METHODS: A mechanism for making fine ice slush was created, and a 10-mm laparoscopic end-effector was designed and constructed for deployment of the ice slush. The novel ice slush deployment system was tested in a porcine model and compared with that of standard open ice slush cooling. After atraumatic hilar clamping, the cortical and medullary temperatures in the upper, middle, and lower poles were measured with thermocouples. RESULTS: Six pigs were evaluated in each group. In all cases, the kidneys were successfully cooled to our goal temperature of 15 degrees to 25 degrees C within 10 minutes and were maintained at the target temperature for 1 hour. The core body temperature for the slush group was decreased by 3 degrees C but did not change in the open group. The renal temperatures quickly returned to normal on unclamping of the renal hilum. One pig in the open group died of acidosis and another in the same group experienced thrombosis of the renal artery. No complications occurred in the laparoscopic group. CONCLUSIONS: We describe a novel, simple-to-use mechanism for producing and delivering fine ice slush in a laparoscopic setting. The technique achieves optimal parenchymal hypothermia expeditiously.

Animals↗
PubMed2005

Evaluation of surgical models for renal collecting system closure during laparoscopic partial nephrectomy.

OBJECTIVES: To evaluate the utility of the porcine and canine models for collecting system closure after partial nephrectomy involving violation of the renal collecting system. Advanced surgical technologies and novel techniques for performing laparoscopic partial nephrectomy are frequently evaluated in an animal model. METHODS: After evaluation of the upper urinary tract with retrograde pyelography, laparoscopic partial nephrectomy, including violation of the renal collecting system, was performed in 8 domestic pigs (group 1) and 2 dogs (group 2) with documented normal upper urinary tract physiology. No collecting system closure was performed. Subsequently, in an attempt to generate an adequate model for renal collecting system closure, 6 pigs (group 3) underwent partial obstruction of the proximal ureter before laparoscopic partial nephrectomy without collecting system closure. After 3 weeks, the animals underwent evaluation, including retrograde pyelography, and were killed for histopathologic evaluation of the upper urinary tracts. RESULTS: Despite documented transection of major calices in all animals, none with physiologically normal upper urinary tracts developed urinomas. After partial occlusion of the proximal ureter, all pigs had hydronephrosis, but only one of six developed a urinoma. CONCLUSIONS: The porcine and canine models are inadequate for evaluating renal collecting system closure after partial nephrectomy. Our high-pressure partial occlusion model was similarly inadequate. The limitations of these animal models should be considered when reviewing published data regarding technologies for partial nephrectomy. Future data regarding novel technologies for partial nephrectomy should also be carefully considered before clinical application.

Animals↗
PubMed2005

Comparison of optical resolution with digital and standard fiberoptic cystoscopes in an in vitro model.

OBJECTIVES: To compare two different distal sensor flexible endoscopes with standard fiberoptic cystoscopes for optical resolution. Distal video sensor flexible endoscopy may represent the cusp of a new endoscopic revolution. METHODS: Twenty-three participants evaluated the optical resolution capabilities of six flexible cystoscopes. The two presently available distal sensor flexible cystoscopes, ACMI DCN-2010 digital flexible cystoscope and Olympus CYF-V EndoEYE flexible video cystoscope, were compared with the four leading fiberoptic cystoscopes, ACMI ACN-2 fiberoptic cystoscope, Olympus CYF-4 Cystofiberscope, Karl Storz 11272CU1 Flexible Cystoscope, and Richard Wolf Flexible Fibre Urethro-Cystoscope, in an in vitro model. The participants recorded the numerical digits they were able to visualize through five solutions with progressively increasing concentrations of hematoxylin dye (C1 to C5). The cystoscopic images were viewed on a 13-in. medical grade Olympus monitor with an Olympus Visera camera system. RESULTS: No differences were detected among the cystoscopes at the lowest concentrations of hematoxylin dye (C1 and C2). At C3 to C5, the mean percentage of visualized numbers for the ACMI and Olympus distal sensor flexible cystoscopes was significantly greater than for all fiberoptic cystoscopes (P <0.01). At the highest concentration (C5), the ACMI distal sensor cystoscope performed significantly better than did the Olympus distal sensor flexible cystoscopes (P <0.01), although at all other concentrations, the two digital video cystoscopes performed equivalently. CONCLUSIONS: The results of this in vitro study suggest that cystoscopes with distal sensor technology improve visibility in a simulated challenging working environment compared with fiberoptic cystoscopes.

Cystoscopes↗
PubMed2005

Prospective evaluation of learning curve for laparoscopic radical prostatectomy: identification of factors improving operative times.

OBJECTIVES: To evaluate the time required for each component of laparoscopic radical prostatectomy (LRP) performed by a single surgeon to identify the factors that expedite the learning curve. LRP is a technically demanding procedure with a lengthy learning curve. METHODS: The LRP procedure was divided into 12 steps, and the time for each step was prospectively recorded during the first 50 consecutive patients undergoing LRP by a single surgeon. The operations were divided into five groups of 10, and the average times for each step were compared and correlated with surgeon observations and changes in surgical technique. RESULTS: Statistically significant progressive improvement was seen in the total time of the LRP procedure (269.4 minutes in period 1 versus 205.4 minutes in period 4, P < 0.05). Regarding the specific steps, improvement occurred in the time needed for dissection of the vas deferens and seminal vesicles (51.8 minutes for period 1 versus 25.3 minutes for period 4, P < 0.01 and 31.2 minutes for period 5, P < 0.03), apical incision (16.7 minutes for period 1 versus 6.3 minutes for period 4, P < 0.03 and 5.7 minutes for period 5, P < 0.02), and division of the rectourethralis (13.5 minutes for period 1 versus 3.4 minutes for period 5, P < 0.05). The time needed for vesicourethral anastomosis remained unchanged throughout the study (average 48.5 minutes). CONCLUSIONS: With experience, the operative times for defined components of LRP improve. Patient selection for a low body mass index and smaller prostate may expedite the procedure. Application of a fixed retractor system, early identification of the vas deferens beneath the peritoneum in a more lateral position, and slow meticulous dissection and ligation of the dorsal vein complex are factors that may expedite the learning curve for LRP.

Clinical Competence↗
PubMed2005

Extrarenal vascular anatomy of kidney: assessment of variations and their relevance to partial nephrectomy.

OBJECTIVES: To evaluate the feasibility of selective segmental artery clamping during partial nephrectomy. METHODS: Precise extraparenchymal renal hilar dissection was performed on 73 fixed cadaveric kidneys. The surgical accessibility to clamping of each presegmental and segmental artery from the anterior and posterior approaches was determined on the basis of vessel length, position within the renal hilum, and degree of overlying collecting system or venous structures. RESULTS: The vascular anatomy consisted of zero, one, or two presegmental arteries (extrarenal main renal artery branches that split into two or more segmental arteries) in 49.3%, 31.5%, and 19.2% of the kidneys, respectively. From a posterior approach, the posterior segmental artery was accessible to isolated clamping in 81.8% of the kidneys (segmental accessibility rate) and was accessible to clamping at the presegmental level in 12.7% (presegmental accessibility rate) for a total accessibility rate of 90.9%. The total accessibility rate for the inferior segmental artery was 88.5% from an anterior and 66.7% from a posterior surgical approach. The apical artery total accessibility rate was 72.3% and 40.5% from an anterior and posterior approach, respectively. The corresponding middle and superior segmental artery total accessibility rates were 50.8% and 32.8%. CONCLUSIONS: In this cadaveric model, hilar dissection and clamping of the renal segmental arteries is anatomically feasible in most cases. Posterior and polar tumors will likely be more amenable to segmental vascular control. Selective segmental vascular control may offer the benefits of total hilar control while reducing overall renal ischemic injury.

Cadaver↗
PubMed2005

Comparison of second-generation hand-assisted laparoscopic devices for surgeon pain and arm circulation.

OBJECTIVES: To compare two second-generation hand-assist devices (HADs) for surgeon pain and manual blood flow over time in an in vitro model. METHODS: Nineteen participants placed their nondominant hand through both the LapDisc and GelPort into a pneumoperitoneum chamber with an insufflation pressure of 15 mm Hg for a 2-hour test period. Pain, on a 10-point visual analog scale, and manual blood flow to the index finger using a laser Doppler skin probe were measured at 10 points during the 2 hours. Participants completed a questionnaire regarding hand comfort and the physical effects of the HAD. RESULTS: At 30, 45, and 60 minutes after hand insertion, the pain scores were significantly greater for the GelPort than for the LapDisc (P = 0.04, P = 0.01, and P = 0.03, respectively). The GelPort caused an immediate reduction in manual blood flow, and the LapDisc caused a small initial increase in manual blood flow (P = 0.03) and, thereafter, a decrease in blood flow. Three participants voluntarily removed their hand at 30, 45, and 60 minutes owing to the pain from GelPort use. No participant withdrew from the LapDisc because of pain. CONCLUSIONS: Both HADs resulted in surgeon discomfort in our in vitro model. The GelPort resulted in more subjective pain compared with the LapDisc. Both HADs caused a reduction in manual blood flow. However, compared with the LapDisc, the GelPort caused significantly more reduction in manual blood flow. Surgeon comfort is only one parameter to consider when choosing a HAD.

Arm↗
PubMed2005

Laparoscopic renal surgery and the risk of rhabdomyolysis: diagnosis and treatment.

Postoperative rhabdomyolysis is a rare but serious complication of laparoscopic renal urologic surgery. The early recognition and treatment of the condition are imperative to minimize the risk of acute renal failure (ARF) and to limit the associated physical debility. Between 1992 and 2003, > 700 laparoscopic renal procedures were performed at 2 institutions. Rhabdomyolysis occurred in 7 patients. Patient records were retrospectively analyzed for operative, postoperative, and convalescence data. Rhabdomyolysis presented in all patients as excessive, immediate postoperative muscular pain in the "downside" hip/flank. The average procedure time among these patients was 7.5 hours (range, 5.8 to 9.4 hours). In 6 of 7 cases, the kidney rest was elevated throughout the procedure. Two patients required emergency fasciotomy to treat a gluteal compartment syndrome. Four patients (57%) experienced ARF with an average peak creatinine of 533.8 micromol/L [7.0 mg/dL] (range, 160.1 to 739.6 micromol/L [2.1 to 9.7 mg/dL]). These patients had bicarbonate alkalinization and diuretic administration initiated at a mean of 24 hours (range, 4 to 48 hours). Two patients required hemodialysis for 1 month postoperatively but had stable serum creatinine (106.8 and 129.6 micromol/L [1.4 and 1.7 mg/dL]) within 2 months. The mean peak serum creatinine kinase (CK) for all patients was 33,912 U/L (range, 9350 to 99,193 U/L). All patients had extended recovery with difficulties including lower extremity weakness (n = 4), local pressure neuropathy (n = 1), long-term leg pain and numbness (n = 1), and disability requiring long-term wheelchair assistance (n = 1). Excessive, immediate postlaparoscopic gluteal muscular pain should prompt immediate evaluation of serum CK to assess for rhabdomyolysis. Aggressive hydration and diuresis are recommended to minimize renal injury. Minimizing operative times, attention to padding of the operative table, and eliminating or limiting the use of a kidney rest may help prevent this complication.

Humans↗
PubMed2005

Comparison of running and interrupted vesicourethral anastomoses in a porcine model.

PURPOSE: To compare running and interrupted suturing techniques for porcine vesicourethral anastomosis with regard to procedure time, histopathologic effects, and leakage. MATERIALS AND METHODS: Twelve domestic pigs were randomized to a running (N = 6) or an interrupted (N = 6) vesicourethral anastomosis with polyglycolic acid sutures. In each case, the bladder was drained for 7 days. A cystogram was performed immediately after completion of each anastomosis and on postoperative days 7 and 30. Animals were sacrificed on postoperative day 30, and the area of the anastomosis was excised en bloc for histopathologic evaluation. RESULTS: All procedures were completed laparoscopically. The mean operative time for continuous and interrupted suturing were 27.5 and 36.8 minutes, respectively (P = 0.3324). A significant learning curve was noted for both anastomoses, with operative times decreasing with experience in both groups. There was no difference in anastomotic leakage. Histopathology examination revealed more muscle-layer fibrosis in the interrupted- suture group than in the continuous-suture group, with a mean score of 2.17 and 1.67, respectively (P = 0.0325). CONCLUSIONS: Both continuous and interrupted vesicourethral anastomoses are feasible. In this in-vivo porcine comparison, there was no difference with respect to procedure time or anastomotic leakage. However, histopathologic grading demonstrated greater muscle fibrosis in the interrupted-suture group.

Anastomosis, Surgical↗
PubMed2005

Impact of a double-pigtail stent on ureteral peristalsis in the porcine model: initial studies using a novel implantable magnetic sensor.

BACKGROUND AND PURPOSE: The effect of stents on ureteral peristalsis in vivo is not entirely clear. We sought to develop a minimally invasive method for its study. MATERIALS AND METHODS: In female domestic pigs, electrical potentials from the ureter were measured by bipolar steel-wire electromyography electrodes delivered laparoscopically. Mechanical movement was measured by giant magneto resistive sensors mounted on custom-made aluminum strips. After baseline values were obtained, the animals were randomized to receive silicone or polyurethane stents, and ureteral peristalsis was measured for 8 hours acutely and for 4 hours 1 week later. RESULTS: Implantation of the devices took an average of 30 minutes. A consistent correlation was found between laparoscopically observed peristaltic waves and the peristalsis detected by the two measuring devices. The devices themselves did not affect peristalsis. Stent insertion increased peristaltic activity initially but later reduced or stopped it. There was no difference in the effects of the two types of stents. CONCLUSIONS: The new technique permits close monitoring of ureteral peristalsis in vivo. Smaller stents appear to have less immediate effect than larger ones, but all type of stents tested eventually caused aperistalsis.

Animals↗
PubMed2005

Comparison of a novel endoscope holder and traditional camera assistant for laparoscopic simple nephrectomy in a porcine model.

PURPOSE: To establish the feasibility of single-surgeon laparoscopy with application of a novel endoscope-holder device and to compare this technique with traditional assistant-driven laparoscopic camera control. MATERIALS AND METHODS: Bilateral simple nephrectomies were performed in six pigs. On one side, the operating surgeon employed the "scope holder" and performed the surgery without a laparoscopic assistant. On the contralateral side, an experienced camera operator was responsible for control of the laparoscopic field of vision in the traditional manner. The time required for hilar ligation and complete renal mobilization was documented. Pigs were sacrificed immediately after the procedure. RESULTS: The mean operative times for scope-holder and camera person-assisted nephrectomy were 20.7 minutes and 19.3 minutes, respectively. The time to hilar ligation in the scope-holder and camera-operator-assisted cohorts was 13 and 14.5 minutes, respectively. There were no significant differences in operative times or blood loss in the two groups. The operative surgeon perceived some increase in shoulder and neck pain with use of the scope holder. CONCLUSIONS: This novel device provides a means for the operative surgeon to safely perform a laparoscopic nephrectomy alone without significantly increasing operative time or morbidity.

Animals↗
PubMed2005

Laparoscopic ureterocalicostomy: development of a technique simplified by application of Nitinol clips and a wet monopolar electrosurgery device.

PURPOSE: We developed a technique for laparoscopic ureterocalicostomy with the use of intracorporeal suturing and subsequently simplified the technique by application of experimental Nitinol clips. MATERIALS AND METHODS: We performed laparoscopic ureterocalicostomy on 16 domestic swine divided into four groups of four animals each. The kidney was exposed laparoscopically, and the renal artery was atraumatically clamped. The lower pole of the kidney was amputated to expose a lower-pole calix, and hemostasis of the cut renal surface was obtained with a wet monopolar electrosurgical device (Floating Ball device [FB]; TissueLink, Dover, NH). Anastomosis of the ureter to the lower-pole calix was performed over a guidewire using 3-0 Vicryl suture in group 1 and Nitinol clips in group 3. A double-J ureteral stent was then deployed retrograde under fluoroscopic guidance. In addition, we evaluated the use of fibrin glue as a sealant over the sutured or clipped anastomotic site (groups 2 and 4, respectively). Ureteral stents were removed after 3 weeks, and the animals were evaluated and sacrificed after an additional 3 weeks. RESULTS: Laparoscopic ureterocalicostomy was completed in all 16 animals. In each case, excellent renal parenchymal hemostasis was obtained with the FB device, with a mean hemostasis time of 4.1 minutes. The mean anastomotic time with standard suture reconstruction was 37.1 +/- 5.4 minutes, while the anastomotic time with the Nitinol clips was 29.0 +/- 8.0 minutes (P = 0.0339). Retrograde pyelograms in groups 1 and 3 (no fibrin glue) showed a patent anastomosis with no hydronephrosis in three of the four animals in each group. One animal in group 1 and one animal in group 3 developed large urinomas secondary to anastomotic failure. The animals that received fibrin glue over the anastomotic site (groups 2 and 4) all showed narrowed anastomoses with severe hydronephrosis. CONCLUSIONS: With available instrumentation, laparoscopic ureterocalicostomy is technically feasible. Nitinol clip technology significantly reduces collecting-system reconstruction time. Application of fibrin glue as a urinary tract sealant resulted in an unexpected adverse outcome.

Alloys↗
PubMed2005

Evaluation of intra-abdominal pressures and gas embolism during laparoscopic partial nephrectomy in a porcine model.

PURPOSE: Gas embolization is a well documented complication of laparoscopic surgery. We evaluated the association of gas embolization with increased intra-abdominal pressure (IAP) in the porcine model during laparoscopic partial nephrectomy with real-time transesophageal echocardiography. MATERIALS AND METHODS: Eight domestic pigs weighing 143 to 162 pounds underwent unilateral transperitoneal laparoscopic heminephrectomy with renal artery clamping with varied IAPs. The renal vein was not clamped, allowing the exposure of venous tributaries to the pneumoperitoneum. IAP was increased in 5 mm Hg increments in 4 pigs each by 1) insufflation pressure adjustment to a maximum of 30 mm Hg and 2) intermittent application of an argon beam coagulator (ABC) to the cut kidney surface. Transesophageal echocardiography was used to monitor embolism. RESULTS: None of the 4 animals subjected to increased CO2 insufflation pressure (maximum 30 mm Hg) demonstrated gas embolization during partial nephrectomy. The ABC caused gas embolization during partial nephrectomy at an IAP of 30 to 50 mm Hg in 4 animals. The volume of embolized gas was 4 to 20 ml. None of the animals showed intraoperative hemodynamic compromise. CONCLUSIONS: Gas embolization was not seen during laparoscopic partial nephrectomy with typical insufflation pressures. The ABC can rapidly increase IAP and cause argon embolization at IAPs greater than 30 mm Hg. Prophylactic maneuvers to prevent gas embolization, such as intra-abdominal venting or renal vein clamping, should be considered when applying the ABC.

Animals↗
PubMed2004

Laparoscopic radical prostatectomy: a multi-institutional study of conversion to open surgery.

OBJECTIVES: To perform a multi-institutional review of the incidence and factors contributing to conversion from laparoscopic radical prostatectomy (LRP) to open radical retropubic prostatectomy (RRP) among eight surgeons. METHODS: The medical records from all patients undergoing LRP at seven institutions were reviewed to assess the incidence of open conversion to RRP. The clinical, operative, pathologic, and functional outcomes of patients who required conversion were compiled and analyzed. RESULTS: Of 670 operations, 13 (1.9%) were converted from LRP to RRP. The most common steps at which conversion occurred were the apical dissection (38%) and the posterior seminal vesicle dissection (31%). Failure to progress was the most common cause of conversion, followed by injury to adjacent structures and hypercarbia. Comorbidities associated with conversion were prior pelvic surgery and obesity (body mass index greater than 30). Six of the 13 conversions occurred in the surgeons' first 5 cases. Despite open conversion, patients were continent (no pads) (92%) and potent (44%) with at least 6 months of follow-up. CONCLUSIONS: Open conversion from LRP to RRP is an uncommon event, but is more likely to occur during a surgeon's early experience. Surgeons beginning their experience with LRP are advised to select their patients carefully to minimize the need for conversion to open surgery. Obese patients and those at risk of periprostatic adhesions should initially not be considered for LRP. Despite open conversion, the functional outcomes did not appear to be adversely affected.

Adenocarcinoma↗
PubMed2004

Enhanced renal cryoablation with hilar clamping and intrarenal cooling in a porcine model.

OBJECTIVES: To evaluate the effects of renal vascular control and intrarenal cooling on the size of renal lesions attainable with a 3.4-mm cryoprobe. METHODS: Three groups of pigs underwent unilateral laparoscopic renal cryoablation with a 3.4-mm cryoprobe inserted to a depth of 1 cm. An 8-minute double-freeze cycle was used. One week later, an acute contralateral cryolesion was created before killing the animal. In group 1 (n = 6), bilateral cryolesions were created without hilar clamping or intrarenal cooling. In group 2 (n = 6), the cryolesions were created after hilar clamping alone. In group 3 (n = 6), the cryolesions were created after both hilar clamping and application of intrarenal cooling with saline ice-slush infused into the renal pelvis. After nephrectomy, the gross diameters were determined for each cryolesion. The mean diameters of the zones of complete and partial necrosis were determined by histopathologic examination. RESULTS: In group 3, the cortex cooled from 36.9 degrees C to a mean of 24.8 degrees C. Acutely, no statistically significant difference was found between the lesions produced with clamping alone (37.6 mm) and intrarenal cooling (40.4 mm); however, both were significantly larger than the control cryolesions (28.7 mm). At 1 week, the area of complete necrosis produced with intrarenal cooling (34.3 mm) was significantly larger than the areas of necrosis produced by clamping alone (27.8 mm) or conventional cryoablation (23.9 mm; alpha = 0.05, Tukey's honestly significantly different [HSD] test). CONCLUSIONS: Enhanced cryolesion necrosis was achieved with intrarenal cooling with a 3.4-mm cryoprobe. Intrarenal cooling may be a valuable adjunct to cryoablation in selected cases.

Animals↗