Cytotoxic T cell immunity against the non-immunogenic, murine, hepatocellular carcinoma Hepa1-6 is directed towards the novel alternative form of macrophage colony stimulating factor.

Mouse Hepa1-6 hepatocellular carcinoma (HCC) cells were transduced with the membrane form of macrophage colony stimulating factor (mM-CSF). When mM-CSF transduced Hepa1-6 cells were injected subcutaneously into mice, these cells did not form tumors. The spleens of these immunized mice contained cytotoxic CD8+ T lymphocytes (CTL) that killed the unmodified Hepa1-6 cells. We show that the alternative form of macrophage colony stimulating factor (altM-CSF) induced CTL-mediated immunity against Hepa1-6 cells. AltM-CSF is restricted to the H-2D(b) allele. CTLs killed RMA-S cells loaded with exogenous altM-CSF peptide. Vaccination of mice with dendritic cells pulsed with the altM-CSF peptide stimulated anti-Hepa1-6 CTLs. Hyper-immunization of mice with mM-CSF Hepa1-6 cells showed inflammation of the liver and kidneys. Although altM-CSF was expressed within liver and kidney cells, its intensity was lower than Hepa1-6 cells. AltM-CSF was detected within the human HepG2 cell line. These studies suggest that altM-CSF may be a tumor antigen for HCC.

Comparative study of in vivo lymphatic sealing capability of the porcine thoracic duct using laparoscopic dissection devices.

PURPOSE: Sealing the lymphatic vessels during abdominal and pelvic surgery is important to prevent the leakage of lymphatic fluid and its resultant sequelae. To our knowledge we compared for the first time the quality of lymphatic sealing by each of 4 commonly used laparoscopic dissection devices. MATERIALS AND METHODS: A total of 12 domestic pigs were used to test dissecting devices, including monopolar scissors (Ethicon Endo-Surgery, Cincinnati, Ohio), Harmonic ACE Scalpel, LigaSure V, EnSeal and Trissector. A midline incision was made from mid sternum to umbilicus, the diaphragm was divided and the porcine thoracic duct was isolated. In all animals each device was used to seal an area of the duct and each seal was placed at least 2 cm from the prior seal. In group 1 the thoracic duct of 6 pigs was cannulated with a 5Fr catheter and the seal was subjected to burst pressure testing using a burst pressure measuring device (Cole-Parmer, Vernon Hills, Illinois). In the 6 pigs in group 2 each seal was immediately sent for histopathological evaluation. Specimens were given a score for the extent of cautery damage, including 0-none, 1-minimal, 2-moderate, 3-severe and 4-extreme. RESULTS: A total of 64 seals were created, of which 35 were subjected to burst pressure testing. Mean size of the thoracic duct was 2.6 mm. No acute seal failures were observed with any bipolar device or the harmonic shears. However, 2 immediate failures (33%) were seen with monopolar scissors. Mean burst pressure for monopolar scissors, Harmonic ACE Scalpel, LigaSure V, EnSeal and Trissector was 46 (range 0 to 165), 540 (range 175 to 795), 258 (range 75 to 435), 453 (range 255 to 825) and 379 mm Hg (range 175 to 605), respectively (p <0.05). Trissector, Harmonic ACE Scalpel and EnSeal generated seals with significantly higher burst pressure than that of monopolar scissors (p <0.05). Histopathological evaluation revealed that LigaSure caused less thermal damage than Trissector and EnSeal (p <0.05). CONCLUSIONS: Each device tested except monopolar scissors consistently produced a supraphysiological seal and should be suitable for sealing lymphatic vessels during laparoscopic surgery.

Rapid communication: robot-assisted NOTES nephrectomy: initial report.

BACKGROUND AND PURPOSE: Natural Orifice Transluminal Endoscopic Surgery (NOTES) using the daVinci robot (Intuitive Surgical, Sunnyvale, CA) has never been applied to urologic surgery. Here we present our initial experience with a combined transvaginal and transcolonic, single-port, robot-assisted NOTES nephrectomy. METHODS: An acute experiment was performed in a female farm pig. A single 12-mm trocar was placed in the midline, and two 12-mm standard laparoscopic ports were placed into the abdomen via the vagina and the colon. The robotic ports were then telescoped into the 12-mm ports, and the daVinci S robot was docked. Dissection was performed using the Hot Shears and the ProGrasp instruments. The robotic camera was placed via the midline port and held by an assistant. Using the 12-mm transvaginal port, the renal artery and vein were divided separately with a vascular Endo GIA (US Surgical, Norwalk, CT) stapler. The kidney was placed into a 10-mm entrapment sack and removed intact via the vagina. RESULTS: Total operative time was 150 minutes. Estimated blood loss was less than 50 mL. No intraoperative complications occurred. CONCLUSION: A robot-assisted NOTES nephrectomy was accomplished in a porcine model using the daVinci S robot. Additional testing on survival animals is necessary to further explore this approach.

Development of a novel iPad-based laparoscopic trainer and comparison with a standard laparoscopic trainer for basic laparoscopic skills testing.

INTRODUCTION: We developed the iTrainer (iT) as a portable laparoscopic trainer, which incorporates the iPad tablet. We then compared the iT with a standard pelvic trainer (SPT) to assess surgical skills as well as its image quality, resolution, brightness, comfort, and overall performance. MATERIALS AND METHODS: We designed and constructed the iT to be compatible with the Apple iPad 3 and standard laparoscopic instruments. Participants were assigned to perform the thread-the-loops task on both trainers and were prospectively randomized to start on either the iT or the SPT. Each participant was allowed a 2-minute warm-up before the 2-minute testing period. We scored participants using the product of skill quality (0-4 scale) and quantity of loops threaded (0-10 scale). Participants then rated each trainer on image quality, resolution, brightness, comfort, and overall performance on a 5-point Likert scale. RESULTS: A total of 45 subjects including 10 undergraduates, 10 medical students, 10 general surgery and urology residents, and 15 experts (fellows and attending surgeons) participated in this study. There was no significant difference between thread-the-loops task scores completed on the iT when compared with the SPT for all groups tested (p > 0.05) with the exception of the medical student group, who performed better on the SPT (p < 0.05). On evaluation of each trainer, participants rated the iT as having superior image quality and resolution when compared with the SPT (p < 0.05) but rated the SPT higher in overall performance (p < 0.05). Brightness and comfort were rated similarly for both trainers. CONCLUSIONS: We have demonstrated face validity and criterion validity for the thread-the-loops task on the iT. The iT rated superior in image quality and resolution but inferior in overall performance compared with the SPT. The iT provides trainees a unique advantage over SPT as an additional resource to laparoscopic training as it is inexpensive, portable, and can be readily available for training.

In vitro evaluation of ScopeSafe fibers and the scope guardian sheath in prevention of ureteroscope endolumenal working damage.

BACKGROUND AND PURPOSE: Ureteroscope breakage is commonly related to laser fiber damage. Often, the damage is mechanical and not energy related. As such, we evaluated a novel laser fiber and sheath system in preventing mechanical ureteroscope damage during fiber insertion. MATERIALS AND METHODS: We assessed 200-µm/272/3-µm laser fibers with the laser sheath in a flexible ureteroscope. Diminishment of active deflection and irrigation flow rates were compared with a standard laser fiber alone. Eight nonassembled working channel components were tested in a 0-degree/90-degree/210-degree deflection model. After insertion cycles, external and endolumenal damage to the working channel were classified. We also tested the sheath system in a 0-degree/90-degree/210-degree deflection model for fiber failure and laser damage. RESULTS: In all test trials with the sheath and for standard laser fibers in the 0-degree model, there were no channel perforations or damage. With standard laser fibers, in the 210-degree model, superficial scratches and demarcated abrasions were visible after 10 and 60 to 70 insertions for the 273-µm laser fiber and after 30 insertions (superficial scratches) for the 200-µm laser fiber. In the 90-degree model, superficial scratches occurred after 20 insertions for the 273-µm fibers and after 40 insertions for the 200-µm laser fibers. No demarcated abrasions were seen after 100 insertions. In the 210-degree model, there was one perforation with the 272-µm fiber, but none with 200-µm fiber. There were no fiber failures with sheath use; however, the sheath did not prevent laser energy damage. The laser sheath resulted in a 4.7-degree/3.8-degree (1.2%/1.5%) diminishment in deflection (up/down) for the 200 µm and a 3.5-degree/4.3-degree (1.8%/1.5%) diminishment for 272-µm laser fiber compared with standard 200/272-µm laser fiber. Irrigation flow was diminished with the sheath on both the 200-µm and 272-µm laser fiber by 28.7% and 32.6%, respectively. CONCLUSION: The Scope Guardian Sheath prevented mechanical working channel damage with minimal diminishment of deflection and irrigation flow.

Comparison of optics and performance of a distal sensor high definition cystoscope, a distal sensor standard definition cystoscope, and a fiberoptic cystoscope.

OBJECTIVE: To evaluate performance characteristics and optics of a new generation high-definition distal sensor (HD-DS) flexible cystoscope, a standard-definition distal sensor (SD-DS) cystoscope, and a standard fiberoptic (FO) cystoscope. METHODS: Three new cystoscopes (HD-DS, SD-DS, and FO) were compared for active deflection, irrigation flow, and optical characteristics. Each cystoscope was evaluated with an empty working channel and with various accessories. Optical characteristics (resolution, grayscale imaging, color representation, depth of field, and image brightness) were measured using United States Air Force (USAF)/Edmund Optics test targets and illumination meter. We digitally recorded a porcine cystoscopy in both clear and blood fields, with subsequent video analysis by 8 surgeons via questionnaire. RESULTS: The HD-DS had a higher resolution than the SD-DS and the FO at both 20 mm (6.35 vs 4.00 vs 2.24 line pairs/mm) and 10 mm (14.3 vs 7.13 vs 4.00 line pairs/mm) evaluations, respectively (P <.001 and P <.001). Color representation and depth of field (P = .001 and P <.001) were better in the HD-DS. When compared to the FO, the HD-DS and SD-DS demonstrated superior deflection up and irrigant flow with and without accessory present in the working channel, whereas image brightness was superior in the FO (P <.001, P = .001, and P <.001, respectively). Observers deemed the HD-DS cystoscope superior in visualization in clear and bloody fields, as well as for illumination. CONCLUSION: The new HD-DS provided significantly improved visualization in a clear and a bloody field, resolution, color representation, and depth of field compared to SD-DS and FO. Clinical correlation of these findings is pending.

High-fidelity simulation-based team training in urology: evaluation of technical and nontechnical skills of urology residents during laparoscopic partial nephrectomy.

INTRODUCTION: The use of low-risk simulation training for resident education is rapidly expanding as teaching centers integrate simulation-based team training (SBTT) sessions into their education curriculum. SBTT is a valuable tool in technical and communication skills training and assessment for residents. We created a unique SBTT scenario for urology residents involving a laparoscopic partial nephrectomy procedure. MATERIALS AND METHODS: Urology residents were randomly paired with a certified registered nurse anesthetists or an anesthesia resident. The scenario incorporated a laparoscopic right partial nephrectomy utilizing a unique polyvinyl alcohol kidney model with an embedded 3cm lower pole exophytic tumor and the high-fidelity SimMan3G mannequin. The Urology residents were instructed to pay particular attention to the patient's identifying information provided at the beginning of the case. Two scripted events occurred, the patient had an anaphylactic reaction to a drug and, after tumor specimen was sent for a frozen section, the confederate pathologist called into the operating room (OR) twice, first with the wrong patient name and subsequently with the wrong specimen. After the scenario was complete, technical performance and nontechnical performance were evaluated and assessed. A debriefing session followed the scenario to discuss and assess technical performance and interdisciplinary nontechnical communication between the team. RESULTS: All Urology residents (n = 9) rated the SBTT scenario as a useful tool in developing communication skills among the OR team and 88% rated the model as useful for technical skills training. Despite cuing to note patient identification, only 3 of 9 (33%) participants identified that the wrong patient information was presented when the confederate "pathologist" called in to report pathology results. CONCLUSION: All urology residents rated SBTT sessions as useful for the development of communication skills between different team members and making residents aware of unlikely but potential critical errors in the OR. We will continue to use SBTT as a useful method to develop resident technical and nontechnical skills outside of the high-risk operating environment.

Tracking and assessment of technical skills acquisition among urology residents for open, laparoscopic, and robotic skills over 4 years: is there a trend?

BACKGROUND AND PURPOSE: Tracking the progression of technical skill acquisition during urology residency training is an essential yet challenging task that has been mostly based on anecdotal and subjective performance assessment. We evaluated five surgical tasks used at our institution to assess skill acquisition among residents over 4 consecutive years in an effort to determine appropriate skill testing for resident proficiency relative to level of training for future performance testing. METHODS: Urology residents were tested yearly throughout the course of their residency with five surgical tasks in an open, laparoscopic, and robotic format. The five tasks were: (1) rings on a peg, (2) thread the rings, (3) cut the line, (4) hexagonal suturing, and (5) suture and knot tying. Evaluation was performed by a trained instructor to assess quantity and quality of the skill task performance. RESULTS: The highest scores were obtained on all open tasks regardless of training level. Residents performed second best on robotic and lowest on the laparoscopic skill tasks. The score difference among surgery platforms was statistically significant P<0.0005 across all tasks. It was Tasks 2 and 5, however, that showed a statistically significant difference in overall quantity×quality score between different postgraduate year (PGY) residents (P=0.03 and P=0.02). In addition, the quantity score for Task 5 also showed a statistically significant difference among PGY residents (P=0.04). There was no statistically significant difference in time to perform tasks among PG years. CONCLUSIONS: The high-level Tasks 2 and 5 were the most useful in differentiating different levels of skill task competency among urology residents and appear to be most useful in assessing the degree of improvement among residents during training. These tasks have subsequently been worked into our institution's testing curriculum.

Bovine serum albumin glutaraldehyde for completely sutureless laparoscopic heminephrectomy in a survival porcine model.

INTRODUCTION: Laparoscopic partial nephrectomy (LPN) has not received widespread clinical application because of its technical challenge. Bovine serum albumin glutaraldehyde (BSAG) is a hemostatic agent that is independent of the clotting cascade. We evaluated the use of BSAG as the sole agent for parenchymal and collecting system closure during LPN in a survival porcine model. METHODS: Eighteen pigs underwent hilar clamping and LPN by longitudinal excision of the lateral one-third of the right kidney. The opened collecting system was covered with oxidized cellulose to prevent BSAG seepage into the urinary tract. BSAG was allowed to set for 10 or 5 minutes. Twelve animals underwent survival LPN BSAG only closure; six control pigs were acutely studied using saline. Urinary extravasation was evaluated by injection of furosemide and indigo carmine, and then evaluating the renal surface and bladder catheter drainage for dye. A subjective bleeding score was assigned after hilum unclamping. At 6 weeks, BSAG kidneys were harvested for burst pressure testing and histopathological analysis. RESULTS: All 12 pigs survived for 6 weeks. No pigs had urinary extravasation. Mean percentage of kidney removed by weight was 19%. Mean warm ischemia time was 29 minutes. Five pigs required a second BSAG application to achieve a bleeding score of 0. Mean arterial and collecting system burst pressures were 301.8 and 322.4 mm Hg, respectively. Mean postoperative creatinine increase was 0.07 mg/dL. CONCLUSION: BSAG for completely sutureless LPN in a survival porcine model was feasible.

Evaluation of the outcomes of electrosurgical induced bowel injury treated with tissue glue/sealant versus sutured repair in a rabbit model.

INTRODUCTION: Bowel injury is an uncommon, although potentially devastating, intraoperative laparoscopic complication. Questions have been raised about the possible use of a tissue adhesive to repair injured bowel. We compared glued repair and sutured repair of both large bowel (LB) and small bowel (SB) electrosurgical injuries in a rabbit model. METHODS: Pneumoperitoneum was obtained, and four laparoscopic ports were placed in each of 48 New Zealand rabbits. The hook electrode was used in a specified manner to create an equal number of uniform full-thickness injuries to either the SB or the LB. Laparoscopic repair was performed with a 3-0 silk Lembert suture (LS), fibrin glue (FG), or BioGlue (BG), or repair was not performed (i.e., no repair, NR); the animals were monitored for 3 weeks. Adverse clinical outcomes and findings at laparotomy were recorded. Pathologic assessment included an objective scaled evaluation of the intensity of the inflammatory response and degree of healing. RESULTS: In the SB injury group, deteriorating clinical condition necessitated early euthanasia in one animal repaired with FG, one animal repaired with BG, and two animals with NR. LS repair animals had no adverse clinical outcomes. The LB injury group had no adverse clinical outcomes regardless of the method of repair, including the control group. Of the animals that survived for 3 weeks, the animals repaired with BG had more intraabdominal adhesions (100%) than LS (33%), FG (55%), and NR (50%) (p = 0.001). The pathologic assessment revealed that BG induced a more intense inflammatory response (p < 0.05). CONCLUSION: In the rabbit, suture repair of an electrosurgical SB injury appears to have improved outcomes when compared with a glued repair. In contrast, LB injury responded well to any form of treatment. The data suggest that suture is superior to biological glues when dealing with a laparoscopic electrosurgical bowel injury.

LapED 4-In-1 silicone training aid for practicing laparoscopic skills and tasks: a preliminary evaluation.

OBJECTIVE: We developed a simple, inexpensive model to simulate four reconstructive laparoscopic procedures: pyeloplasty, vesicourethral anastomosis, bladder injury repair, and partial nephrectomy. MATERIALS AND METHODS: Liquid silicone was applied in layers to a mold to create the 4-in-1 model. A questionnaire evaluating its face and content validity was distributed to postgraduate urologists participating in a mini-residency program at the University of California-Irvine (UCI), and in the 2006 American Urological Association Hands-On course on reconstructive laparoscopic pyeloplasty. RESULTS: A total of 56 postgraduate urologists used the model and completed an evaluation questionnaire. Ninety-four percent (51/54) and 96% (48/50) agreed that the model was helpful for practicing laparoscopic pyeloplasty and urethrovesical anastomosis, respectively. Urologists who were experienced in either performing laparoscopic pyeloplasty (n = 6) or robot-assisted and/or laparoscopic prostatectomy (n = 11) would recommend this model to surgeons in training. Overall, 94% (48/51) and 96% (50/52) of the respondents would recommend this model for postgraduate surgeons and residents, respectively. CONCLUSION: We present a versatile model for practicing laparoscopic and robotic suturing and knot-tying skills in four reconstructive urologic procedures. Our results support the face and content validity of this model for performing pyeloplasty and vesicourethral anastomoses.

Third place: Flank position is associated with higher skin-to-surface interface pressures in men versus women: implications for laparoscopic renal surgery and the risk of rhabdomyolysis.

BACKGROUND AND PURPOSE: There have been several reports of rhabdomyolysis occurring after prolonged laparoscopic procedures in the flank position. Accordingly, we evaluated interface pressures between the skin and three commonly used operating room table surfaces. The aim of our study was to determine if pressure changes could be related to body mass index (BMI), sex, position, and/or the table surface material. PATIENTS AND METHODS: Ten men and 10 women were grouped according to BMI <25 or >or=25, with five participants in each group. Subjects were placed in the left lateral decubitus position with the operating table flat, half flexed, fully flexed, half flexed with the kidney rest elevated, and fully flexed with the kidney rest elevated. Interface pressures were recorded, using an X-Sensor pressure sensing mat, for 5-minute periods in each of the described positions on each surface. RESULTS: Sex and BMI were statistically significant predictors of increased pressures (P= 0.0042 and 0.0402, respectively). The parameter estimate for the difference between men and women was 4.63 mm Hg (P= 0.0002), and the difference for BMI >or= 25 compared with <25 was also significant (P < 0.0209). Full table flexion (50-degree) produced significantly higher pressures than both flat (P= 0.0001) and the half-flexed (25-degree) position (P < 0.0001). Positions with the kidney rest elevated were associated with significantly higher pressures than without elevation (P < 0.0001). With regard to the surface used, egg crate provided lower pressures than gel pads (P= 0.0117). CONCLUSION: Women have significantly lower interface pressures when compared with men. BMI >or= 25 also increases interface pressures. The use of the kidney rest is associated with markedly increased pressure; use of a half-flexed position is preferable to a full-flexed position. These data have implications for patient positioning and identification of persons at risk for rhabdomyolysis during laparoscopic renal surgery.

Antiangiogenic drugs synergize with a membrane macrophage colony-stimulating factor-based tumor vaccine to therapeutically treat rats with an established malignant intracranial glioma.

Combining a T9/9L glioma vaccine, expressing the membrane form of M-CSF, with a systemic antiangiogenic drug-based therapy theoretically targeted toward growth factor receptors within the tumor's vasculature successfully treated >90% of the rats bearing 7-day-old intracranial T9/9L gliomas. The antiangiogenic drugs included (Z)-3-[4-(dimethylamino)benzylidenyl]indolin-2-one (a platelet-derived growth factor receptor beta and a fibroblast growth factor receptor 1 kinase inhibitor) and oxindole (a vascular endothelial growth factor receptor 2 kinase inhibitor). A total of 20-40% of the animals treated with the antiangiogenic drugs alone survived, while all nontreated controls and tumor vaccine-treated rats died within 40 days. In vitro, these drugs inhibited endothelial cells from proliferating in response to the angiogenic factors produced by T9/9L glioma cells and prevented endothelial cell tubulogenesis. FITC-labeled tomato lectin staining demonstrated fewer and constricted blood vessels within the intracranial tumor after drug therapy. Magnetic resonance imaging demonstrated that the intracranial T9 glioma grew much slower in the presence of these antiangiogenic drugs. These drugs did not affect in vitro glioma cell growth nor T cell mitogenesis. Histological analysis revealed that the tumor destruction occurred at the margins of the tumor, where there was a heavy lymphocytic infiltrate. Real-time PCR showed more IL-2-specific mRNA was present within the gliomas in the vaccinated rats treated with the drugs. Animals that rejected the established T9/9L glioma by the combination therapy proved immune against an intracranial rechallenge by T9/9L glioma, but showed no resistance to an unrelated MADB106 breast cancer.