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Jaime Landman

Publications and source records attributed to Jaime Landman.

At least 55 records · Page 3Linked to original sources
PubMed2004

Needle-based ablation of renal parenchyma using microwave, cryoablation, impedance- and temperature-based monopolar and bipolar radiofrequency, and liquid and gel chemoablation: laboratory studies and review of the literature.

BACKGROUND AND PURPOSE: Small renal tumors are often serendipitously detected during the screening of patients for renal or other disease entities. Rather than perform a radical or partial nephrectomy for these diminutive lesions, several centers have begun to explore a variety of ablative energy sources that could be applied directly via a percutaneously placed needle-like probe. To evaluate the utility of such treatment for small renal tumors/masses, we compared the feasibility, regularity (consistency in size and shape), and reproducibility of necrosis produced in normal porcine kidneys by different modes of tissue ablation: microwaves, cold impedance-based and temperature-based radiofrequency (RF) energy (monopolar and bipolar), and chemical. Chemoablation was accomplished using ethanol gel, hypertonic saline gel, and acetic acid gel either alone or with simultaneous application of monopolar or bipolar RF energy. MATERIALS AND METHODS: A total of 107 renal lesions were created laparoscopically in 33 domestic pigs. Microwave thermoablation (N=12) was done using a Targis T3 (Urologix) 10F antenna. Cryoablation (N=16) was done using a single 1.5-mm probe or three 17F microprobes (17F SeedNet system; Galil Medical) (N=10 single probe and N=6 three probes); a double freeze cycle with a passive thaw was employed under ultrasound guidance. Dry RF lesions were created using custom-made 18-gauge single-needle monopolar probe with two or three exposed metal tips (GelTx) (N=12) or a single-needle bipolar probe (N=6) at 50 W of 510 kHz RF energy for 5 minutes. In addition, a multitine RF probe (RITA Medical Systems) was used in one set of studies (N=6). Both impedance- and temperature-based RF were evaluated. Chemoablation was performed with 95% ethanol (4 mL), 24% hypertonic saline (4 mL), and 50% acetic acid (4 mL) as single injections. In addition, chemoablation was tested with monopolar and bipolar RF (wet RF). Tissues were harvested 1 week after ablation for light microscopy. RESULTS: In 11 of the 15 ablation techniques, there was complete necrosis in all lesions; however, three ethanol gel lesions had skip areas, three hypertonic saline gel lesions showed no necrosis or injury, and one monopolar RF and one bipolar RF lesion showed skip areas. In contrast to impedance-based RF, heat-based RF (RITA) caused complete necrosis without skip areas. All cryolesions resulted in complete tissue necrosis, and cryotherapy was the only modality for which lesion size could be effectively monitored using ultrasound imaging. CONCLUSIONS: Cryoablation and thermotherapy produce well-delineated, completely necrotic renal lesions. The single-probe monopolar and bipolar RF produce limited areas of tissue necrosis; however, both are enhanced by using hypertonic saline, acetic acid, or ethanol gel. Hypertonic saline gel with RF consistently provided the largest lesions. Ethanol and hypertonic saline gels tested alone failed to produce consistent cellular necrosis at 1 week. In contrast, RITA using the Starburst XL probe produced consistent necrosis, while impedance-based RF left skip areas of viable tissue. Renal cryotherapy under ultrasound surveillance produced hypoechoic lesions, which could be reasonably monitored, while all other modalities yielded hyperechoic lesions the margins of which could not be properly monitored with ultrasound imaging.

Acetic Acid↗
PubMed2004

Laparoscopic radical prostatectomy: Washington University initial experience and prospective evaluation of quality of life.

BACKGROUND AND PURPOSE: The laparoscopic approach to radical prostatectomy offers an alternative to the open surgical procedure with less morbidity. We prospectively collected data including a validated quality-of-life questionnaires on our first 38 laparoscopic radical prostatectomies (LRPs). The first 10 patients (group 1), second 10 patients (group II), and the most recent 18 patients (group III) were examined separately to study the learning curve for this procedure. In addition, we determined the pattern of recovery of urinary continence, potency, and quality of life. PATIENTS AND METHODS: Between July 1999 and July 2002, 38 consecutive transperitoneal laparoscopic radical prostatectomies were performed for clinically localized prostate carcinoma. Patients completed quality-of-life questionnaires (Rand 36 Health Survey) before surgery as well as at 1, 3, 6, and 12 months and every 6 months thereafter. The patients were also interviewed by an individual not directly involved in patient care. RESULTS: One patient (the second in our experience) was converted to the open approach because of failure to progress. The average operating time for the whole series was 423 +/- 137.6 minutes (range 215-825 minutes), the last 10 procedures taking 305 +/- 63 minutes (range 215-420 minutes). Complications consisted of one case each of intraoperative bladder injury, transient superficial peroneal nerve palsy, pulmonary embolism, and bladder neck obstruction. The bladder injury was closed laparoscopically without further complication. Bladder neck obstruction was secondary to a bladder wall fold that was treated with transurethral resection 14 months after surgery with good results. Four patients in group 1 had minor anastomotic leaks, while only one patient after that had a leak (group III). Four patients required transfusion, two intraoperatively and two postoperatively. In group III, the urethral catheter remained in place for an average of 8 days (range 6-10 days). With a mean follow-up of 22.8 months (range 9-43 months), 84.8% of the patients had perfect urinary control. Postoperatively, 9 patients (27%) were fully continent on removal of the Foley catheter. At 1, 3, 6, and 9 months postoperatively, diurnal urinary control was reported by 30.3%, 48%, 72.7%, and 84.8% of the patients, respectively. One patient needed an artificial urinary sphincter. Among the incontinent patients, 24.2% had urinary urgency, and one third of these patients reported urge incontinence. CONCLUSIONS: Laparoscopic prostatectomy is a reproducible technique with a steep learning curve. Operating times and the incidence of anastomotic leaks and urinary incontinence decrease significantly after the initial 10 patients.

Erectile Dysfunction↗
PubMed2004

Laparoscopic sacrocolpopexy for the correction of vaginal vault prolapse.

BACKGROUND AND PURPOSE: Laparoscopic sacrocolpopexy offers a minimally invasive approach to correcting vaginal vault prolapse. We describe our operative technique and review our experience. PATIENTS AND METHODS: A retrospective study of 10 patients who underwent laparoscopic sacrocolpopexy between February 2000 and June 2002 for posthysterectomy vaginal vault prolapse was performed. Data collected included operative time, complications, hospital stay, and postoperative morbidity. RESULTS: One patient underwent primary laparoscopic repair of an intraoperative bladder injury. Conversion from a laparoscopic to an open procedure was required in one patient because of dense bowel adhesions in the pelvis. The mean analgesic (morphine sulfate equivalent) requirement was 7.3 mg (range 5-21 mg). With a mean follow-up of 16 months (range 5-32 months), prolapse recurred in one patient. CONCLUSION: In the short term, laparoscopic sacrocolpopexy appears to be an effective approach for the treatment of vaginal vault prolapse with minimal postoperative pain and morbidity.

Adult↗
PubMed2004

Application of a fixed retractor system to facilitate laparoscopic radical prostatectomy.

PURPOSE: We report application of a fixed retractor system for reduction of the steep Trendelenberg position required to achieve deep pelvic access for laparoscopic radical prostatectomy. MATERIALS AND METHODS: A fixed retractor system consisting of a flexible arm that can be locked in position and an expandable 5 mm laparoscopic retractor were used to gain exposure to the deep pelvis. We describe in detail our technique for laparoscopic radical prostatectomy incorporating the fixed retractor system to facilitate each step of the procedure. RESULTS: Application of the fixed retractor system reduced steep Trendelenberg position requirements for adequate pelvic exposure from 25 to 15 degrees in our most recent 24 laparoscopic radical prostatectomies. Furthermore, application of the retractor system reduced the need for an experienced laparoscopic assistant. CONCLUSIONS: Application of the fixed retractor system for laparoscopic radical prostatectomy eliminated the requirement for the steep Trendelenberg position to achieve access to the deep pelvis. Visceral structures were safely and indefatigably retracted from the operative field. The technique also allowed the surgical assistant to assist the surgeon with local retraction and aspiration.

Equipment Design↗
PubMed2004

Comprehensive evaluation of ureteral healing after electrosurgical endopyelotomy in a porcine model: original report and review of the literature.

PURPOSE: Endopyelotomy (EP) has yet to equal the success achieved with open dismembered pyeloplasty. To understand better the ureteral response to EP we performed a timed histopathological evaluation of the porcine ureter after Acucise (Applied Medical, Rancho Santa Margarita, California) EP. MATERIALS AND METHODS: In 28 domestic pigs bilateral Acucise EPs were performed and bilateral 7Fr stents were placed. The kidneys, ureters and bladder were harvested after EP at 0, 1, 2, 3, 6, 12 and 18 hours, 1, 3 and 5 days, and 1, 2, 4 and 8 weeks. The stents were removed after 4 weeks. The healing area of the ureter was sectioned. Half was fixed in formalin 10%, stained and evaluated by light microscopy. The other half was frozen and reverse transcriptase-polymerase chain reaction was performed to measure steady state levels of epidermal growth factor, transforming growth factor (TGF)-alpha, TGF-beta 1, TGF-beta 2, TGF-beta 3, keratinocyte growth factor, vascular endothelial growth factor, insulin-like growth factor, platelet derived growth factor, collagen type 1, integrin and fibronectin transcript expression. Immunohistochemistry for actin, desmin and myosin expression was completed. The same studies were applied to the mid portion of the unoperated ureter. RESULTS: Initial sealing of the ureterotomy defect was by blood clot and periureteral fat. Complete healing of the mucosa was observed at 2 weeks in animals without an associated urinoma. However, in no case did the muscle layer bridge the whole circumference of the ureter despite followup out to 8 weeks. In the operated ureter elevated expression of keratinocyte growth factor, vascular endothelial growth factor, TGF-alpha, TGF-beta 1, TGF-beta 3 and integrin was detected 2 hours after the operation and sustained for 7 to 14 days after the procedure. Immunohistochemistry revealed that most presumed myocytes seen in the defect were actually myofibroblasts. Persistent urinoma formation beyond the first few days appeared to slow the healing process. CONCLUSIONS: Urothelium regenerated rapidly over an iatrogenic ureteral defect despite the absence of a lamina propria. Muscle cell coverage failed to occur completely at 8 weeks. In the initial 8 weeks of the healing process myofibroblasts appear to be prevalent. A persistent urinoma negatively impacts the healing process.

Animals↗
PubMed2004

Prospective comparison of the immunological and stress response following laparoscopic and open surgery for localized renal cell carcinoma.

PURPOSE: We prospectively compared the systemic immune and stress response of patients who underwent laparoscopic total nephrectomy (LRN) (14) and open nephrectomy (ON) (10) for renal cell carcinoma. The ON group comprised open radical (4), open total (2) and open partial (4) nephrectomy cases. MATERIALS AND METHODS: Only patients with no history of cancer or autoimmune disease and American Society of Anesthesiologists score 2 or less who were not using immunosuppressive drugs were selected. Peripheral venous blood was collected preoperatively and intraoperatively, and 24 hours, 2 weeks, 4 weeks and 3 months postoperatively. Blood was analyzed for stress markers (adrenalin, noradrenalin and cortisol), inflammatory response markers (C-reactive protein, white blood count and leukocyte count), lymphocytic response markers (CD3, CD4 and CD8), cytokines interleukin-2 and 4, interferon-alpha and tumor necrosis factor-alpha), HLA-DR expression and the proliferative response to mitogen stimulation using concanavalin A, phytohemagglutinin 10, and pokeweed mitogen. RESULTS: Mean tumor size +/- SD for ON and LRN was 5.6 +/- 2.4 and 4.5 +/- 1.6 cm, respectively (p = 0.21). The trends with time for all measured postoperative parameters were similar in the 2 groups. Inflammatory and stress response markers were statistically similar for in the groups at all time points. A significant difference between the groups was noted for the percentage of CD4+ and CD8+ lymphocytes. However, this difference was present preoperatively and there was no significant absolute change in these 2 parameters. The cytokine response and HLA-DR expression were similar in the 2 groups at all time points. Likewise, the lymphocytic stimulation index for concanavalin A, phytohemagglutinin and pokeweed mitogen were statistically similar for LRN and ON at all time points. CONCLUSIONS: The immunological and stress response after LRN and ON for renal cell carcinoma is similar. The few differences observed in measured parameters likely reflect preoperative differences in baseline and/or the contributory effect of anesthesia.

Carcinoma, Renal Cell↗
PubMed2004

Laparoscopic mid sagittal hemicystectomy and bladder reconstruction with small intestinal submucosa and reimplantation of ureter into small intestinal submucosa: 1-year followup.

PURPOSE: We evaluated the long-term results of laparoscopic hemicystectomy and bladder replacement with small intestinal submucosa (SIS) with ureteral reimplantation into the SIS material. MATERIALS AND METHODS: A total of 12 minipigs underwent laparoscopic hemicystectomy. Six pigs underwent bladder reconstruction with SIS and ipsilateral ureteral reimplantation. The remaining 6 control pigs underwent hemicystectomy and primary bladder closure with ipsilateral nephroureterectomy. Preoperative and followup evaluations included blood chemistry, radiography and urodynamic evaluations. The 6, 3, 6 and 9-week, and 12-month followup evaluations included biopsies. At 1 year the animals were sacrificed. Histopathological and contractility studies, and reverse transcriptase-polymerase chain reaction for growth factors and basement membrane components were performed. RESULTS: Bladder capacity and bladder compliance were similar in the 2 groups at all time points. One pig per group died, that is a control at the 9-month evaluation due to an anesthetic complication and an SIS pig 7 months after bladder reconstruction due to spontaneous bladder rupture at the anastomotic site. In the SIS group 4 of 5 surviving pigs had unobstructed reimplanted ureters without evidence of hydroureteronephrosis, while 1 had high grade obstruction at the reimplantation site. Histopathology study after 1 year revealed muscle at the graft periphery and center but it consisted of small fused bundles with significant fibrosis. Nerves were present at the graft periphery and center but they were decreased in number. CONCLUSIONS: Laparoscopic SIS bladder reconstruction and ureteral reimplantation into the SIS after hemicystectomy are technically feasible. However, compared to primary bladder closure no advantage in bladder capacity or compliance was documented.

Animals↗
PubMed2004

Prospective randomized comparison of 2 ureteral access sheaths during flexible retrograde ureteroscopy.

PURPOSE: While the use of ureteral access sheaths facilitates flexible ureteroscopy, buckling or kinking of the device may preclude its successful application. We evaluate the ability of 2 hydrophilic coated ureteral access sheaths to obtain and maintain access to the upper collecting system. MATERIALS AND METHODS: A total of 54 flexible ureteroscopy procedures were randomized to use of the 12/15Fr Applied Access Forte XE (Applied Medical, Rancho Santa Margarita, California) or the 12/14Fr Cook Flexor (Cook Urological, Spencer, Indiana) access sheaths. Device failure was defined as buckling of the sheath that prevented adequate placement, kinking of the sheath after removal of the obturator or difficulty in passing instruments through the sheath. The ease of placement, instrument passage and stone extraction was scored from poor (1) to excellent (4). Fisher's exact test and Mann-Whitney tests were used for statistical comparisons. RESULTS: No patient required ureteral balloon dilation. There was no significant difference between the groups in regard to preoperative stenting (34% and 31%, p = 1.00) or rigid ureteroscopy before sheath placement (32% and 25%, p = 0.751). The device failure rate was 44% for the Applied sheath and 0% for the Cook sheath (p <0.001). Failures with the Applied sheath included buckling (25%), kinking (25%) and difficulty passing instruments (13%). The Cook sheath was rated superior with regard to ease of placement (3.89 vs 3.00, p = 0.001), ease of instrument passage (3.97 vs 3.29, p = 0.001) and ease of stone extraction (3.74 vs 3.00, p = 0.023). CONCLUSIONS: The performance of the Cook Flexor sheath was superior with regard to overall failure and ease of use.

Adult↗
PubMed2003

Combined percutaneous and retrograde approach to staghorn calculi with application of the ureteral access sheath to facilitate percutaneous nephrolithotomy.

PURPOSE: We describe our technique and clinical experience with application of the ureteral access sheath for single access ablation of staghorn and partial staghorn calculi. MATERIALS AND METHODS: We retrospectively reviewed our experience with 9 patients who underwent percutaneous nephrolithotomy for staghorn (6) or partial staghorn (3) renal calculi using a combined antegrade and retrograde approach. Patient data, operative parameters, efficacy of stone ablation and convalescence parameters were reviewed. RESULTS: Mean operative time for the primary procedure was 3.1 hours with a mean estimated blood loss of 290 ml. Postoperatively, the mean analgesic requirement was 33.2 mg. MSO(4) equivalents. Hospital stay was 3.2 days. There were no major and 4 minor (44%) complications. No patient required transfusion. Complete stone clearance was achieved in 7 of the 9 cases (78%) using a single percutaneous nephrostomy tract. CONCLUSIONS: Our preliminary clinical experience using the ureteral access sheath during percutaneous nephrolithotomy for simultaneous antegrade and retrograde stone treatment has been favorable. A large renal stone burden can be successfully managed with a single percutaneous access and limited blood loss.

Humans↗
PubMed2003

Characterization of intrapelvic pressure during ureteropyeloscopy with ureteral access sheaths.

OBJECTIVES: To evaluate the impact of the ureteral access sheath on intrarenal pressures during flexible ureteroscopy in light of the recent resurgence in their use. As such, using human cadaveric kidneys, we studied changes in intrarenal pressure in response to continuous irrigation at different pressures with and without access sheaths of various sizes and lengths. METHODS: This study was performed using seven cadaveric kidneys. In three kidneys the study was done in situ with a 7.5F flexible ureteroscope (URS) passed by itself and then passed through a 10/12F sheath (35 and 55 cm in length), whereas, in four kidneys, due to narrowing of the intramural ureter, the study was done ex vivo using the unsheathed URS and then passing the 7.5F flexible URS via the 10/12F, 12/14F, and 14/16F sheaths (all 35 cm in length). A 10F Cope loop pyelostomy was placed to measure intrapelvic renal pressure. Three sets of 3-minute readings (ie, flow and intrarenal pressure) were taken with the tip of the URS at the distal ureter, middle ureter, and renal pelvis (just above the ureteropelvic junction); the entire process was done at three different irrigant pressure settings: 50, 100, and 200 cm H(2)O. Irrigant flow and intrarenal pressures were measured at all three settings using the URS passed without a sheath and then with the URS passed through the various sheaths positioned at the distal ureter, middle ureter, and renal pelvis. RESULTS: With all of the sheaths, intrapelvic pressure remained low (less than 30 cm H(2)O), and there was a 35% to 80% increase in irrigant flow versus the control unsheathed URS. With the sheath in place, the majority of the irrigant drained alongside the URS and out the sheath. Flow and pressure with the 12/14F sheath were equivalent to the 14/16F sheath. CONCLUSIONS: The 12/14F access sheath provides for maximum flow of irrigant while maintaining a low intrarenal pelvic pressure. Even with an irrigation pressure of 200 cm H(2)O, renal pelvic pressure remained below 20 cm H(2)O.

Equipment Design↗
PubMed2003

Hemostatic laparoscopic partial nephrectomy assisted by a water-cooled, high-density, monopolar device without renal vascular control.

OBJECTIVES: To evaluate the feasibility of laparoscopic partial nephrectomy assisted by a water-cooled, high-density, monopolar device (TissueLink Floating Ball). METHODS: Transperitoneal laparoscopic partial nephrectomy was performed without vascular control for four renal tumors in 3 patients. A flexible ultrasound probe was used to confirm tumor location and depth. Gerota's fascia was opened distant from the tumor site. Renal fat was dissected from the renal parenchyma except for the fat overlying the tumor. The tumor resection area was marked 1 cm outside the boundaries of the tumor. After application of the TissueLink Floating Ball at the planned surgical margin, the tumor was resected with cold laparoscopic scissors. Bleeding from the vessels of the divided renal parenchyma was controlled with the Floating Ball if necessary. The specimen was sent for frozen section to confirm margin status. RESULTS: Mean estimated blood loss per tumor was 275 mL. The dissection extended to the collecting system in 2 of 4 cases. In 1 patient, a minor postoperative urine leak resolved spontaneously. CONCLUSIONS: Use of the TissueLink Floating Ball facilitated resection of small renal tumors without renal vascular control. Although further study is necessary, water-cooled, high-density monopolar energy may have a role in laparoscopic partial nephrectomy.

Aged↗
PubMed2003

Renal hypothermia achieved by retrograde endoscopic cold saline perfusion: technique and initial clinical application.

We describe the technique and initial clinical results with application of a novel method to achieve renal parenchymal hypothermia using retrograde ureteral access. A 38-year-old man was scheduled to undergo an open right partial nephrectomy for renal cell carcinoma. Before the open procedure, a ureteral access sheath was advanced to the ureteropelvic junction under fluoroscopic guidance; through the access sheath, a 7.1F pigtail catheter was also advanced. After clamping the renal artery and vein, ice-cold saline (-1.7 degrees C) was circulated through the access sheath and drained via the 7.1F pigtail catheter; renal cortical and medullary parenchymal temperatures were measured using thermocouples. This technique of intrarenal cooling achieved a renal cortical temperature of 24 degrees C and a medullary temperature of 21 degrees C. The endoscopic procedure required an additional 35 minutes of operation time to complete. Histopathologic investigation of the specimen revealed no associated damage to the ureteral urothelium from access sheath placement or to the collecting system urothelium from exposure to ice-cold saline irrigation. Retrograde endoscopic renal hypothermia is feasible and effective. The technique requires no novel equipment or special surgical skills. This method can be applied to patients undergoing open or laparoscopic complex renal ablative and reconstructive procedures that require renal hypothermia.

Adult↗
PubMed2003

Evaluation of overall costs of currently available small flexible ureteroscopes.

OBJECTIVES: To perform a meta-analysis of the currently available data regarding the durability of flexible ureteroscopes to establish cost estimates for the purchase and use of five currently available, smaller than 9F, ureteroscopes. Healthcare costs have become increasingly germane to the determination of disease management strategies. Improved ureteroscope technology has expanded the role of these instruments. However, the initial purchase costs and high maintenance costs have become problematic with these fragile instruments. METHODS: Ureteroscope durability data on the Storz 11274AA, Olympus URF-P3, Wolf 7325.172, ACMI AUR-7, and ACMI DUR-8 were collected from three prior studies. Combining the durability data and cost data regarding the initial purchase price and maintenance costs of these instruments, we calculated the overall costs associated with the use of each of the ureteroscopes for 25, 50, 75, and 100 cases during the first year (warranties included) and with subsequent use. RESULTS: The variability in the costs associated with the use of the currently available smaller than 9F ureteroscopes was significant. The initial instrument purchase price, durability, repair costs, and associated warranties all contributed to large discrepancies in the cost of performing ureteroscopy. In this model, during the first year of ownership, the projected cost of performing 100 ureteroscopic cases varied by a difference of 95% depending on the ureteroscope used. CONCLUSIONS: Physicians and institutions that perform ureteroscopy should strongly consider the purchase price, durability, repair cost, and associated warranties before the purchase of small flexible ureteroscopes.

Costs and Cost Analysis↗
PubMed2003

Surgical treatment of renal neoplasia: evolving toward a laparoscopic standard of care.

OBJECTIVES: To determine the extent to which laparoscopy has replaced open surgery for renal malignancy. METHODS: The records of all 537 patients at Washington University who underwent surgery for localized renal malignancies from January 1997 to December 2001 were examined for clinical and pathologic information. RESULTS: The total procedures per year increased from 1997 to 2001, but the distribution of pathologic stages throughout the 5 years was similar. In 1997, laparoscopic approaches were used in 15% of cases; this increased to 65% by 2001. Nephron-sparing surgery (NSS) was used in 31% to 42% of patients yearly, but laparoscopic NSS increased in frequency. By 2001, only 3.3% of T1 tumors were removed by open radical nephrectomy compared with 55% treated by laparoscopic nephrectomy. The rest of the T1 tumors in 2001 were treated by open partial nephrectomy (20.2%) or laparoscopic NSS (21.3%). In 2001, 61% of T2 lesions were treated laparoscopically, an increase from 37% in 1997. Most open radical nephrectomies in 2001 were performed for T3 disease. The number of surgeons performing laparoscopic renal surgery has increased at our institution, from two in 1997, both endourologists, to eight in 2001, representing the entire urology faculty that treats renal cancer. CONCLUSIONS: Laparoscopic radical nephrectomy has replaced open radical nephrectomy for low-stage renal neoplasia. Although laparoscopic NSS is increasing in frequency, it has not yet replaced open partial nephrectomy. At our institution, the laparoscopic approach has become the standard of care when radical nephrectomy is needed for T1 or T2 renal cancer.

Carcinoma, Renal Cell↗
PubMed2003

Modified renal morcellation for renal cell carcinoma: laboratory experience and early clinical application.

OBJECTIVES: To present our modified technique to expedite the entrapment and morcellation process. Standard renal morcellation is typically performed using a 12-mm incision, with the specimen entrapped within a durable LapSac. Because the LapSac does not have a deployment mechanism, its application is technically demanding and time consuming. The recent elimination of the electrical morcellator has also made the morcellation process time consuming and tedious. METHODS: Using an in vitro porcine kidney morcellation model, we compared traditional morcellation (n = 10) with our modified morcellation technique (n = 10). The modified morcellation technique incorporated an EndoCatch entrapment sac and used standard manual morcellation through a 3-cm incision. The 3-cm incision allowed for extracorporeal morcellation, because the specimen could be seen through the abdominal wall defect. Subsequently, we performed 11 laparoscopic radical/total nephrectomies for renal masses using the modified morcellation technique through a 3-cm incision. RESULTS: In this in vitro model, renal specimen morcellation with the standard technique required a mean of 9.4 minutes (16.5 g/min) and modified morcellation required 3.24 minutes (51.24 g/min; P <0.0001). The mean fragment size with standard and modified morcellation was 1.47 and 4.46 g, respectively (P <0.0001). EndoCatch entrapment sack integrity was confirmed in all 10 cases (100%). Clinically, 12 patients underwent modified morcellation of radical nephrectomy specimens. All specimens were renal cell carcinoma, with a mean specimen weight of 724 g. The mean entrapment time was 2 minutes, 40 seconds, and the mean morcellation time was 11 minutes. EndoCatch entrapment sack integrity was confirmed in all cases. At a mean follow-up of 8 months, no trocar site or local recurrences have developed. CONCLUSIONS: Preliminary laboratory and clinical data have demonstrated that the modified morcellation technique is safe and expeditious. The larger fragments that result from the modified technique may facilitate tumor staging. The technique must be performed with great care to prevent sack perforation. Prospective randomized comparison of the modified and standard morcellation techniques and long-term follow-up are required before routine application of this technique.

Animals↗
PubMed2003

Transplant ureter stricture: Acucise endoureterotomy and balloon dilation are effective.

PATIENTS AND METHODS: Eight patients with ureteral stricture after renal transplantation underwent minimally invasive treatment with Acucise incision or balloon dilation. Acucise endoureterotomy was used to treat four patients with strictures at the ureterovesical anastomosis, and balloon dilation was used to treat four patients with a ureteroureterostomy stricture. Success was defined as an acceptable serum creatinine concentration in the absence of hydronephrosis with at least 1 year of follow-up. RESULTS: Acucise endoureterotomy for ureterovesical anastomosis stricture was successful in two of three patients (67%) with a mean follow-up of 20 months. One patient had an indeterminate outcome. Balloon dilation of strictured ureteroureterostomy was successful in three of four patients (75%) with a mean follow-up of 23.7 months. Three of the four patients with previously failed open revision were treated successfully with endourologic techniques. The two patients in whom treatment failed had strictures >/=1.5 cm and manifested comorbidities including diabetes mellitus. CONCLUSION: As our results are comparable to those of other published series, endourologic management of transplant ureteral stenosis is a reasonable strategy.

Adult↗
PubMed2003

Tissue chemoablation.

PURPOSE: To provide an overview of the state of the art of tissue chemoablation in animal and human organs and cancers. We also describe our experience with the feasibility, predictability, and reproducibility of necrosis produced by needle chemoablative therapies including ethanol, hypertonic saline, and acetic acid solutions as well as gels in a porcine renal model. MATERIALS AND METHODS: A MEDLINE search was performed for articles on animal and human tissue chemoablation published since 1965. In addition, at Washington University, experimental chemoablation was performed in pigs with 95% ethanol (4 mL), 24% hypertonic saline (4 mL), or 50% acetic acid (4 mL) solutions as well as in gel form. RESULTS: There is extensive literature on the use of chemoablation for liver metastases; recently, chemoablation of the prostate has become an area of research. Human studies have been limited to patients who are not surgical candidates or to investigational procedures performed prior to definitive prostatic surgery. Animal studies of renal chemoablation as a sole therapy have produced mixed results. In our studies, only acetic acid provided complete necrosis. CONCLUSIONS: To date, ethanol chemoablation has been shown to be feasible and reproducible only for metastatic hepatic carcinoma. In urology, chemoablation is still very much in the investigational stage for both the prostate and the kidney. A significant drawback is that even in the gel form, the spread of the chemoablative substance through the tissue is irregular and unpredictable. In the future, chemoablation may become a more effective modality by combining it with radiofrequency or other energy sources.

Acetic Acid↗