Preliminary study of virtual reality and model simulation for learning laparoscopic suturing skills.

PURPOSE: Repetitive practice of laparoscopic suturing and knot tying can facilitate surgeon proficiency in performing this reconstructive technique. We compared a silicone model and pelvic trainer to a virtual reality simulator in the learning of laparoscopic suturing and knot tying by laparoscopically naïve medical students, and evaluated the subsequent performance of porcine laparoscopic cystorrhaphy. MATERIALS AND METHODS: A total of 20 medical students underwent a 1-hour didactic session with video demonstration of laparoscopic suturing and knot tying by an expert laparoscopic surgeon. The students were randomized to a pelvic trainer (10) or virtual reality simulator (10) for a minimum of 2 hours of laparoscopic suturing and knot tying training. Within 1 week of the training session the medical students performed laparoscopic closure of a 2 cm cystotomy in a porcine model. Objective structured assessment of technical skills for laparoscopic cystorrhaphy was performed at the procedure by laparoscopic surgeons blinded to the medical student training format. A video of the procedure was evaluated with an objective structured assessment of technical skills by an expert laparoscopic surgeon blinded to medical student identity and training format. The medical students completed an evaluation questionnaire regarding the training format after the laparoscopic cystorrhaphy. RESULTS: All students were able to complete the laparoscopic cystorrhaphy. There was no difference between the pelvic trainer and virtual reality groups in mean +/- SD time to perform the porcine cystorrhaphy at 40 +/- 15 vs 41 +/- 10 minutes (p = 0.87) or the objective structured assessment of technical skills score of 8.8 +/- 2.3 vs 8.2 +/- 2.2 (p = 0.24), respectively. Bladder leak occurred in 3 (30%) of the pelvic trainer trained and 6 (60%) of the virtual reality trained medical student laparoscopic cystorrhaphy procedures (Fisher exact test p = 0.37). The only significant difference between the 2 groups was that 4 virtual reality trained medical students considered the training session too short compared to none of those trained on the pelvic trainer (p = 0.04). CONCLUSIONS: There is no significant difference between the pelvic trainer and virtual reality trained medical students in proficiency to perform laparoscopic cystorrhaphy in a pig model, although both groups require considerably more training before performing this procedure clinically. The pelvic trainer training may be more user-friendly for the novice surgeon to begin learning these challenging laparoscopic skills.

Preliminary evaluation of a genitourinary skills training curriculum for medical students.

PURPOSE: Basic urology training in medical school is considered important for many medical and surgical disciplines. We developed a 2-day intensive genitourinary skills training curriculum for medical students beginning their clinical clerkship training years and evaluated the initial experience with this program. MATERIALS AND METHODS: All 94 third-year medical students at the University of California, Irvine were required to participate in a 5.5-hour genitourinary examination skills training program. The teaching course included 1.5 hours of didactic lecture and video presentation with questions and answers, followed by 5, 45-minute hands-on stations including male Foley catheter placement, female Foley catheter placement, testicular examination and digital rectal examination training with a standardized patient, virtual reality cystourethroscopy and, lastly, a urologist led tutorial of abnormal genitourinary findings. The students completed questionnaires before and after the course concerning their experience. At the end of the course the students rated the usefulness of each part of the curriculum and evaluated the faculty. In addition, they were required to complete a multiple choice examination that included 4 genitourinary specific questions. RESULTS: All 94 medical students completed the genitourinary skills training course. Before the course less than 10% of students reported comfort with genitourinary skills, including testicular examination (5%), digital rectal examination (10%), male Foley catheter placement and female Foley catheter placement (2%). Following the course the comfort level improved in all parameters of digital rectal examination (100%) and testicular examination, male Foley catheter placement and female Foley catheter placement (98%). The students rated in the order of most to least useful training 1) standardized patient for testicular examination and digital rectal examination teaching, 2) male Foley catheter placement and female Foley catheter placement training, 3) didactic lecture, 4) tutorial of abnormal genitourinary examination findings and 5) virtual reality cystourethroscopy. On the examination questions following the course 80% to 98% of the class answered each urology content question correctly. CONCLUSIONS: An intensive skills training curriculum significantly improved medical student comfort and knowledge with regard to basic genitourinary skills including testicular examination, rectal examination, and Foley catheter placement in the male and female patient. Further followup will be performed to determine the application of these skills during clinical clerkship rotations.

Retroperitoneal transdiaphragmatic robotic-assisted laparoscopic resection of a left thoracolumbar neurofibroma.

OBJECTIVE: Robotic technology has been used in a variety of surgical procedures for its 3D magnification and precision. Minimally invasive techniques have already become common in neurosurgery; however, robotic-assisted procedures in neurosurgery are still a relatively new frontier. This report describes the first use of robotic technology to resect a left thoracolumbar neurofibroma. CASE REPORT: A 19-year-old male with a family history of neurofibromatosis was diagnosed with a suspected 3-cm x 4-cm neurofibroma in the T12-L1 left paraspinal area. His only complaint was back pain requiring narcotic analgesics. He had no other findings on physical examination or laboratory/radiologic workup. METHODS: After consulting urologic robotic surgeons, it was agreed to use the da Vinci robot (Intuitive Surgical, Sunnyvale, CA) for the resection of this mass. Following retroperitoneal laparoscopic access, the urologic surgeons opened the diaphragm and began the initial mobilization of the mass laparoscopically. The robot was docked, and the neurosurgeon operated the robot at the console to resect the mass from its nerve origin. There were no complications, and the mass, a confirmed neurofibroma, was completely removed. The patient was discharged on postoperative day 2; his back pain resolved, requiring no analgesia by the end of the first postoperative week. CONCLUSION: This case provides early evidence that robotic assistance can be successfully used for the resection of a paraspinal neurofibroma.

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.

Versatile self-complexing compounds based on covalently linked donor-acceptor cyclophanes.

A range of covalently linked donor-acceptor compounds which contain 1) a hydroquinone (HQ) unit, 2) a 1,5-dioxynaphthalene (DNP) ring system, or 3) a tetrathiafulvalene (TTF) unit as the pi-donor, and 4) cyclobis(paraquat-p-phenylene) (CBPQT(4+)) as the pi-accepting tetracationic cyclophane were prepared and shown to operate as simple molecular machines. The pi-donating arms can be included inside the cyclophane in an intramolecular fashion by virtue of stabilizing noncovalent bonding interactions. What amounts to self-complexing/decomplexing equilibria were shown to be highly temperature dependent when the pi-donating arm contains either an HQ or DNP moiety. The thermodynamic parameters associated with the equilibria have been unraveled by using variable-temperature (1)H NMR spectroscopy. The negative DeltaH degrees and DeltaS degrees values account for the fact that the "uncomplexed" conformation becomes the dominant species, since the entropy gain associated with the decomplexation process overcomes the enthalpy loss resulting from the breaking of the donor-acceptor interactions. The arm's in-and-out movements with respect to the linked cyclophanes can be arrested by installing a bulky substituent at the end of the arm. In the case of compounds carrying a DNP ring system in their side arm, two diastereoisomeric, self-complexing conformations are observed below 272 K in hexadeuterioacetone. By contrast, control over the TTF-containing arm's movement is more or less ineffective through the thermally sensitive equilibrium although it can be realized by chemical and electrochemical ways as a result of TTF's excellent redox properties. Such self-complexing compounds could find applications as thermo- and electroswitches. In addition, the thermochromism associated with the arm's movement could lead to some of the compounds finding uses as imaging and sensing materials.