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Jaime Landman

Publications and source records attributed to Jaime Landman.

80 records · Page 5Linked to original sources
PubMed2002

Hydrophilic guide wire technique to facilitate organ entrapment using a laparoscopic sack during laparoscopy.

PURPOSE: Morcellation of the kidney in a LapSac (Cook Surgical, Spencer, Indiana) is reportedly safe and effective during laparoscopic nephrectomy. However, organ entrapment in a LapSac can be difficult, especially during early surgeon experience. A technique to facilitate organ entrapment is described. MATERIALS AND METHODS: We have recently used a simple technique to facilitate deployment of the LapSac in the abdomen using a hydrophilic nitinol guide wire passed through the holes in the mouth of the sack beside its drawstring. The inherent elasticity of the guide wire helps to spring open the mouth of the sack, while facilitating appropriate orientation of the sack mouth. RESULTS: This technique appears to decrease the time needed for organ entrapment because it eliminates the need to triangulate the sack to achieve organ entrapment. An additional port is usually not required during the procedure. CONCLUSIONS: The hydrophilic guide wire technique is inexpensive and effective for LapSac deployment and organ entrapment.

Humans↗
PubMed2002

Evaluation of the use of a biodegradable ureteral stent after retrograde endopyelotomy in a porcine model.

PURPOSE: We evaluated the use of a poly-L-lactide-co-glycolide (PLGA) bioabsorbable ureteral stent after Acucise balloon incision (Applied Medical Resources, Rancho Santa Magarita, California) endopyelotomy in a porcine model. MATERIALS AND METHODS: After unilateral Acucise endopyelotomy in 9 female Yucatan minipigs a self-reinforced PLGA stent was placed in 5 (group 1) and a 7Fr double pigtail Percuflex stent (Boston Scientific, Natick, Massachusetts) was placed in 4 (group 2). Preoperatively, and 6 and 12 weeks postoperatively plain x-ray of the kidneys, ureters and bladder, cystography, side specific creatinine clearance and retrograde ureterography were done. The contralateral ureters served as untreated controls. The 7Fr stents were removed at 6 weeks. All animals were sacrificed at 12 weeks after bilateral flow studies. Histological specimens from 4 sites along the urinary tract were graded on a healing score of 0-normal, to 3-severe changes. RESULTS: Side specific creatinine clearance was similar to preoperative values at 6 and 12 weeks. At the 2 time points plain x-ray of the kidneys, ureters and bladder in group 1 showed retroperitoneal stent fragments in 3 of the 5 animals, which was confirmed at autopsy. Retrograde ureterography in group 1 showed mild hydronephrosis in all 5 ureters and saccular diverticula in 4, which was similar in 2 and 3 animals, respectively, in group 2. Cystography demonstrated grades 1 to 2 reflux in 2 animals at 6 weeks but none at 12 weeks in group 1 and no reflux at either time point in group 2. Flow rates and healing scores were statistically similar in the 2 groups but the latter trended toward less favorable healing of ureteral musculature with application of the absorbable stent. CONCLUSIONS: In this pilot study the use of self-reinforced PLGA biodegradable ureteral stents was feasible after Acucise endopyelotomy in a porcine model with radiographic and fluid flow results that were relatively similar to those of standard 7Fr stents but with less favorable biocompatibility.

Absorbable Implants↗
PubMed2002

Bare naked baskets: ureteroscope deflection and flow characteristics with intact and disassembled ureteroscopic nitinol stone baskets.

PURPOSE: Lower pole renal access during flexible ureterorenoscopy is often limited by the active deflection capabilities of the ureteroscope. Deterioration in the deflection and flow capabilities of ureteroscopes occurs with the passage of instrumentation through the working channel. We performed in vitro evaluation of a novel technique using unsheathed nitinol baskets to minimize the deterioration in deflection and maximize the irrigant flow associated with instrument passage through the working channel during flexible ureterorenoscopy. MATERIALS AND METHODS: Alterations in the irrigant flow and active deflection of 4 ureteroscopes from different manufacturers were evaluated. Each ureteroscope was evaluated with an empty working channel, and then with sheathed and unsheathed 2.2, 3 and 3.2Fr (Cook Urological, Inc., Indianapolis, Indiana), 2.4 and 3Fr (Microvasive Urology, Natick, Massachusetts) nitinol baskets in the working channel. RESULTS: With all baskets tested and in all ureteroscopes the deterioration in active deflection and irrigant flow was improved with the unsheathed baskets. The disassembled basket within the working channel allowed an additional 15 to 20 degrees of active deflection. In addition, the disassembled basket allowed for a 2 to 30-fold increase in irrigant flow compared with an intact basket. CONCLUSIONS: The combination of improved deflection and irrigant flow with this technique may improve ureteroscopic access to lower pole renal calculi.

Alloys↗
PubMed2002

Comparison of hand assisted and standard laparoscopic radical nephroureterectomy for the management of localized transitional cell carcinoma.

PURPOSE: Hand assisted laparoscopy affords the surgeon tactile sensation and blunt dissection, which are currently limited using the standard laparoscopic technique. Therefore, we compared standard and hand assisted laparoscopic radical nephroureterectomy for localized upper tract transitional cell carcinoma. MATERIALS AND METHODS: The medical records of 27 patients who underwent standard (11) or hand assisted (16) laparoscopic radical nephroureterectomy between April 1998 and January 2001 were retrospectively reviewed. The parameters of efficacy, efficiency, safety and convalescence were compared. RESULTS: Mean patient age was 64 and 66 years (p = 0.72) in the standard and hand assisted groups, and the mean American Society of Anesthesiologists score was 2.5 and 2.7 (p = 0.64), respectively. All standard and 15 of the 16 hand assisted (94%) procedures were successfully completed via laparoscopy. Total operative time was more than 1 hour shorter for hand assisted than for laparoscopic radical nephroureterectomy (4.9 versus 6.1 hours, p = 0.055). Mean estimated blood loss was similar in the standard and hand assisted groups (190 and 201 ml., p = 0.78). In each group 1 patient required blood transfusion. Mean specimen weight was significantly higher in hand assisted cases (576 versus 335 gm., p = 0.036). Mean time to oral intake was similar in patients who underwent standard and hand assisted laparoscopic radical nephroureterectomy (13 and 20 hours, respectively, p = 0.45). The mean analgesic requirement was also similar (29 and 33 mg. morphine sulfate, respectively, p = 0.83). Mean hospital stay in uncomplicated cases was similar for standard and hand assisted surgery (2.9 and 2.5 days, respectively). Overall hospital stay in the 2 cohorts was also similar (3.3 and 4.5 days, respectively, p = 0.59). Four patients per group experienced postoperative complications. There were no deaths in the standard group but 1 patient (6%) in the hand assisted group died postoperatively. Mean time to partial and complete convalescence in the standard and hand assisted groups was 2.4 and 5.2, and 3.5 and 8.0 weeks, while mean followup was 27.4 and 9.6 months, respectively. CONCLUSIONS: Compared with standard laparoscopy hand assisted laparoscopy decreases operative time without significantly altering short-term parameters of convalescence. However, long-term convalescence after hand assisted laparoscopic radical nephroureterectomy is 1 to 3 weeks longer (p = 0.27). Longer followup in the hand assisted cohort is necessary to determine whether there are any differences in the 2 methods in regard to cancer control.

Aged↗
PubMed2002

Hand assisted laparoscopic radical nephrectomy for renal cell carcinoma with inferior vena caval thrombus.

PURPOSE: To our knowledge we present the initial clinical report of hand assisted laparoscopic radical nephrectomy for renal cell carcinoma with tumor thrombus extending into the inferior vena cava. MATERIALS AND METHODS: A 76-year-old man was referred to our medical center with a 12.5 x 10 cm. stage T3b right renal tumor extending into the inferior vena cava. The caval thrombus was limited and completely below the level of the hepatic veins. After preoperative renal embolization via the hand assisted transperitoneal approach the right kidney was completely dissected with the renal hilum. Proximal and distal control of the inferior vena cava was obtained with vessel loops and a single lumbar vein was divided between clips. An endoscopic Satinsky vascular clamp was placed on the inferior vena cava just beyond its juncture with the right renal vein, thereby, encompassing the caval thrombus. The inferior vena cava was opened above the Satinsky clamp and a cuff of the inferior vena cava was removed contiguous with the renal vein. The inferior vena cava was repaired with continuous 4-zero vascular polypropylene suture and the Satinsky clamp was then removed. A literature search failed to reveal any similar reports of laparoscopic radical nephrectomy for stage T3b renal cell cancer. RESULTS: Surgery was completed without complication with an estimated 500 cc blood loss. Pathological testing confirmed stage T3b grade 3 renal adenocarcinoma with negative inferior vena caval and soft tissue margins. CONCLUSIONS: The introduction of vascular laparoscopic instrumentation and the hand assisted approach enabled us to extend the indications for laparoscopic radical nephrectomy to patients with minimal inferior venal caval involvement.

Aged↗
PubMedDate not supplied

Intraoperative ultrasonography in urologic oncology.

Ultrasonography is a powerful nonionizing imaging modality that has generally been underused by American Urologists in the past. Innovative investigators and clinicians, however, are realizing the great potential of ultrasonography and are applying it increasingly not only in the clinic but in the operating room. In this commentary we outline some of the current and future uses of intraoperative ultrasonography in urologic oncology.

Diagnostic Imaging↗
PubMedDate not supplied

Determination of cell viability after laparoscopic tissue stapling in a porcine model.

BACKGROUND AND PURPOSE: Surgical stapling devices are often used to secure the distal ureter along with a cuff of bladder during laparoscopic nephroureterectomy. As the viability of cells within the stapled tissue would be important in patients with upper urinary-tract transitional-cell carcinoma, we determined the viability of cells within the lines of various commercially available staplers in a porcine model. MATERIALS AND METHODS: Four laparoscopic stapling devices were used: two vascular and two tissue designs (US Surgical, Norwalk, CT, and Ethicon, Cincinnati, OH). The devices were deployed across a portion of the bladder, much as they would be during a nephroureterectomy to create a bladder cuff while excising the distal ureter. The animals were sacrificed 6 weeks later, and the stapled sites were harvested for histopathologic examination by an experienced genitourinary pathologist (PH). RESULTS: Grossly, there were no visible staples at harvest of the stapled bladder and the ureterovesical junction, with a completely healed bladder being seen in all four animals. On histologic examination with hematoxylin and eosin staining, there were distinctly viable cells within the staple lines of the ureterovesical junction and the bladder wall, similar to the unstapled control tissue. There were viable cells in all samples of tissues stapled by either vascular or tissue staplers. CONCLUSIONS: Deployment of both vascular and tissue staplers resulted in viable cells within the staple lines at the ureterovesical junction and bladder wall in this porcine model. There is a potential risk of tumor recurrence at the stapled site in patients who have the ureter and bladder cuff secured with these devices during laparoscopic nephroureterectomy for upper-tract transitional-cell carcinoma. Despite this concern, to date, over a period of 13 years, clinical experience has not revealed a single case of tumor recurrence within the stapled cuff of bladder. Careful endoscopic evaluation of the stapled bladder-cuff site after laparoscopic nephroureterectomy should minimize the potential for local tumor recurrence.

Animals↗