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Laparoscopic surgery has become the standard of care for many surgical diseases. Haptic (tactile) feedback (HFB) is considered an important component of laparoscopic surgery. Virtual reality simulation (VRS) is an alternative method to teach surgical skills to surgeons in training. Newer VRS trainers such as the Simbionix Lap Mentor II provide significantly improved tactile feedback. However, VRSs are expensive and adding HFB software adds an estimated cost of $30,000 to the commercial price. The HFB provided by the Lap Mentor II has not been validated by an independent party. We used the Simbionix Lap Mentor II in this study to demonstrate the effect of adding an HFB mechanism in the VRS trainer.The study was approved by the University of Cincinnati Institutional Review Board. Twenty laparoscopically novice medical students were enrolled. Each student was asked to perform three different tasks on the Lap Mentor II and repeat each one five times. The chosen tasks demanded significant amount of traction and counter traction. The first task was to pull leaking tubes enough and clip them. The second task was stretching a jelly plate enough to see its attachments to the floor and cut these attachments. In the third task, the trainee had to separate the gallbladder from its bed on the liver. The students were randomized into two groups to perform the tasks with and without HFB. We used accuracy, speed, and economy of movement as scales to compare the performance between the two groups. The participants also completed a simple questionnaire that highlighted age, sex, and experiences in videogame usage.The two groups were comparable in age, sex, and videogame playing. No differences in the accuracy, the economy, and the speed of hand movement were noticed. In fact, adding HFB to the Lap Mentor II simulator did not contribute to any improvement in the performance of the trainees. Interestingly, we found that videogame expert players tend to have faster and more economic motion in their dominant hands. However, the performance accuracy was not significantly affected.The presence of HFB has less effect than it thought to be on the performance of the novice trainees. This may suggest that better HFB is still needed. However, there may be visual compensation for the lack of haptics. Playing videogames has a positive impact on economy, and the speed of the dominant had motion without affecting its accuracy. Further research is needed to clarify the value of haptics to the expert surgeon and compare it to the new trainees.

Background Laparoscopic surgery (LS) is contemplated during long duration space flight, but it typically necessitates intraabdominal hypertension (IAH) from insufflation to create a surgical domain. Because there are spontaneous changes in abdominal wall behavior in weightlessness (0g) that have been previously suggested to increase LS visualization, we studied the comparative laparoscopic visualization between gasless (noGAS), abdominal wall retraction (AWR), and standard 15 mmHg gas insufflation (GAS) during weightlessness. Study Design In-flight LS was performed on four anesthetized pigs during weightlessness obtained through parabolic flight in a research aircraft. GAS was studied during 27 parabolas and compared with 20 parabolas using AWR-LS and 12 with noGAS. Pelvic visualization was scored in real time during flight by 2 or 3 surgeons per parabola and postflight through review of compiled digital video disk (DVD) images by 29 independent reviewers. Physical measurements of the sagittal (anterior-posterior) and transverse dimensions of anesthetized pigs were recorded during 39 parabolas. Results Despite consistent increases in the sagittal abdominal dimension in weightlessness (GAS and noGAS), on-board scored visualization in 0g was unchanged for noGAS (p=0.78) and decreased during AWR (p=0.09), compared with 1g. Although AWR was considered feasible in 1g, spontaneous visceral movements reduced the surgical domain in 0g. Neither AWR nor noGAS was believed safe. But visualization during GAS in 0g was increased over that in 1g (p Conclusions Both noGAS and AWR are impractical in weightlessness. Gas insufflation will be required. With insufflation, visualization and perceived ability to perform LS was improved by weightlessness.

Laparoscopic surgery (LS) is envisioned as an option for spaceflight, but requires intra-abdominal hypertension (IAH) to create the surgical domain. Prolonged weightlessness induces physiologic deconditioning that questions the ability of ill or injured astronauts to tolerate IAH. On earth, IAH results in marked ventilatory embarrassment. As there has been no previous study of physiologic changes related to LS in weightlessness, we studied anesthetized pigs in parabolic flight.Parabolic flight research laboratory.Five anesthetized Yorkshire pigs.Subjects were transported from an animal care facility and secured aboard an aircraft capable of generating hypergravity and weightlessness. Mechanical ventilation was performed using pressure control and positive end-expiratory pressure at 15 and 2 cm H2O, respectively; rate 12 breaths/min. Three abdominal conditions were used during LS: insufflation to produce IAH, abdominal wall retraction (AWR), and no abdominal wall manipulation (baseline). During each parabola breath by breath-tidal volumes (Vt) were recorded by a transport ventilator (HT-50 Newport Medical).Least square means (LS-means) of weight corrected Vt (milliliter per kilogram) by gravity (g) and abdominal condition were determined using a mixed effects model for repeated measures analysis. Increasing gravity (g) consistently reduced Vt (p = 0.0011) as did insufflation (p0.0001). In 1g, Vt (LS-mean 13.7, 95% confidence interval [CI]: 12.4-15.0) was relatively unaffected by AWR (LS-mean 12.8, 95% CI: 11.5-14.00), but markedly decreased by IAH (LS-mean 10.00, 95% CI: 8.9-11.1), an effect accentuated in hypergravity (LS-mean 8.1, 95% CI: 6.4-9.8). In weightlessness, Vt reduction during insufflation was near obviated (LS-mean 12.3, 95% CI: 10.6-14.1), and AWR regularly but inconsistently increased the Vt above 1g baseline (LS-mean 13.7, 95% CI: 11.7-15.8).Weightlessness protects against thoracic compliance changes that are inherent in IAH during induced pneumoperitoneum in gravity. The technique-related physiologic cost of performing LS in space deconditioned astronauts should be incorporated into design concepts for space surgery systems.

Laparoscopy has advanced surgery by allowing the surgeon to operate within a patient's abdominal and pelvic cavity with minimal trauma and scarring. The coupling of a video camera to the laparoscopic telescope has had the secondary effect of allowing others to view the surgical field either on color video monitors or by watching the video feed over the Internet at a remote location. These advancements have allowed better teaching and mentoring of operations. Open procedures can benefit from this technology as well but have suffered in the past from inadequate methods to depict the open surgical field. We used the Alpha Port and Aesop robot to position a sterile laparoscopic telescope near the surgical field to view open cholecystectomies performed on five pigs and to send the video feed over the Internet to remote physicians. Viewing the video on the monitor, the surgeons performed the operation in a comfortable ergonomic upright position. Both the surgeons and the remote physicians found the quality of the video to be excellent, and the remote physicians felt comfortable learning and mentoring surgical procedures using this technique.

The objective of this paper is to determine the effect of varying transmission bandwidth on image quality in laparoscopic surgery. Surgeons located in remote operating rooms connected through a telemedicine link must be able to transmit medical images for interaction. Image clarity and color fidelity are of critical importance in telementoring laparoscopic procedures. The clarity of laparoscopic images was measured by assessing visual acuity using a video image of a Snellen eye chart obtained with standard diameter laparoscopes (2, 5, and 10 mm). The clarity of the local image was then compared to that of remote images transmitted using various bandwidths and connection protocols [33.6 Kbps POTS (IP), 128 Kbps ISDN, 384 Kbps ISDN, 10 Mbps LAN (IP)]. The laparoscopes were subsequently used to view standard color placards. These color images were sent via similar transmission bandwidths and connection protocols. The local and remote images of the color placards were compared to determine the effect of the transmission protocols on color fidelity. Use of laparoscopes of different diameter does not significantly affect image clarity or color fidelity as long as the laparoscopes are positioned at their optimal working distance. Decreasing transmission bandwidth does not significantly affect image clarity or color fidelity when sufficient time is allowed for the algorithms to redraw the remote image. Remote telementoring of laparoscopic procedures is feasible. However, low bandwidth connections require slow and/or temporarily stopped camera movements for the quality of the remote video image to approximate that of the local video image.

Eight patients underwent laparoscopic Roux-en-Y gastric bypass from May 1998 to September 1998 in which a hand-assist technique was used. The operation consisted of a 7.5-cm periumbilical midline incision along with three trocars placed in the upper abdomen. The operative times ranged from 2.25 to 4.5 h. The average preoperative body mass index was 44 kg/m.2 Three-month postoperative follow-up revealed an average weight loss of 59 lb. Cosmetic results to date have been excellent even when compared with those of a total laparoscopic operation. The hand-assist technique allows the surgeon to have more control over the most difficult part of the case, which is manipulation of the small bowel in a morbidly obese abdomen.

The objective of the study was to assess if performance of basic laparoscopic skills on a virtual reality (VR) simulator is impaired in microgravity relative to normal gravitational influences.Fourteen subjects with various educational backgrounds underwent basic laparoscopy skill training for five consecutive days on the ground before flying aboard NASA's KC-135 zero-gravity laboratory. The participants performed basic laparoscopic exercises (clip applying, grasping, cutting, and suturing) on a VR laparoscopy simulator, both on the ground and during 25-s microgravity windows in parabolic flight. Skill levels after ground training were compared with skill levels in performing the same tasks in microgravity. Blinded reviewers measured the number of tasks successfully completed, tissue damage number, left and right hand path lengths during task execution, and percentage of task attempts that resulted in successful completion.A significant increase in tissue injury (t test, P0.05) and task erosion were seen in clip applying, cutting, and grasping in microgravity (45%, 20% and 57% decrease in task attempts that resulted in a successful completion, respectively). However, there was no significant difference in the left and right hand path lengths, and the total number of tasks successfully completed on the ground versus in microgravity, for any of the four laparoscopic exercises (t test, P0.05).This study demonstrates decreased efficiency and increased injury to the simulated tissues in performing laparoscopic skills during microgravity as compared to performing these skills in standard gravitational influence. Additional experiments are indicated to further develop and validate VR microgravity surgical simulation.

Investigators have looked at the effect of night call on surgical residents but not at learning of laparoscopic skills. The Minimally Invasive Surgical Trainer-Virtual Reality (MIST-VR) tests 6 tasks similar to a laparoscopic cholecystectomy. We hypothesized that night call would impair laparoscopic performance and that skills would not improve but rather deteriorate after night call. Seventeen volunteers were tested before and after night call. Data collected included economy of movement, time, and number of errors for each hand/foot. A paired Student t test was used for statistical analysis. On the first 2 tasks, there was an improvement in all parameters post-call, with significance reached in 5 of 18 parameters (P

Previous simulation and porcine experiments aboard the reduced gravity program KC-135 turbojet have demonstrated that microgravity surgery is feasible. Ideally, surgical care in spaceflight will incorporate recent advances in care while remaining easy enough for a crew medical officer (CMO) lacking surgical proficiency or extensive surgical experience to perform. As a minimally invasive surgical technique, hand-assisted laparoscopic surgery (HALS) benefits the patient via smaller incisions, less pain, and faster recovery than traditional open surgery. HALS also helps less experienced laparoscopic surgeons perform laparoscopic surgery.An inexpensive inanimate surgical simulator was constructed to evaluate the usefulness of HALS in microgravity. This simulator was utilized during brief periods of microgravity provided by parabolic flight on the KC-135. The simulator was successfully used by both a physician-astronaut and an experienced laparoscopic surgeon. Task completion included simulated surgery with exploration of the intestines and ligation of the appendix.Simulated HALS was successfully performed in microgravity. HALS effectively contained operative equipment and small amounts of introduced fluids within the simulated abdominal cavity. Astronaut and surgeon experience suggest that HALS could facilitate minimally invasive surgery (MIS) in microgravity.HALS holds promise as a surgical approach in microgravity, particularly as space travel extends beyond low earth orbit. HALS provides the benefits of MIS, facilitates MIS surgery by less surgically proficient or experienced CMOs, and contains equipment and fluid within the operative field. Simulation provides an easy, cost-effective platform to evaluate medical technology for space flight as well as a method to train CMOs on-orbit.

During spaceflight crew health is paramount in the success of flight missions. The delivery of healthcare during flight requires crew readiness for medical and surgical response.There were 20 participants who were evaluated for accurate performance of 4 basic laparoscopic surgical skills (clip applying, cutting, grasping, and suturing) during parabolic weightlessness using an inanimate workstation aboard the NASA KC-135 aircraft.Data indicate that motor skill performance decreased within the parabolic microgravity flight environment. Performance in parabolic microgravity flight included futile effort with an increase in number of tasks attempted and a decrease in tasks completed successfully.There is a decreased frequency of accurate task completion in parabolic microgravity flight, but it is not an obstacle to implementation of effective training for providing in-flight medical care. The data reveal that individuals perform basic laparoscopic surgical simulation with greater effort in microgravity following simulation training.

Background: Certain open surgical procedures are difficult to observe, and poor visualization of the surgical field results in a compromised teaching environment for residents and medical students. In an attempt to improve the visualization of the open surgical field, we performed an open surgical procedure while viewing it via a laparoscope mounted to the side of the operating room table with an alpha port. These images were then compared in a blinded fashion with images from a boom-mounted camera positioned above the surgical field and a head-mounted camera positioned on the operating surgeon. Methods: Participants viewed all 3 images from a remote location in a blinded, random fashion. All participants then completed a Likert questionnaire evaluating each image. Results: Fourteen participants were in the study. The alpha port/laparoscope image was superior to the head-cam image in all 8 categories. The alpha port/laparoscope image was superior to the sky-cam image in 4 of 8 categories. All 14 participants felt the alpha port/laparoscope image would benefit surgical education Conclusions: Use of a laparoscope mounted via an alpha port to an operating room table provides superior images during open surgery. This provides a unique and affordable way to teach residents and medical students operative procedures that are otherwise difficult to view.

Background There clearly must be a surgical capability to support the exploration of the solar system by humans. We hypothesized that microgravity would impair surgical task performance and sought to measure degree and criticality of task erosion. Methods Twenty subjects performed basic laparoscopic exercises (grasping, cutting, clipping, and suturing) in an inanimate trainer on the ground and during the microgravity phase of a parabolic flight. Skill assessment involved time, accuracy, and force transfer. Results A decrease in the total number of on-target task completions was observed in microgravity compared with the ground performance for all tasks. The ratio between the total number of attempts and the number of completions was higher in microgravity. The amount of force introduced into the system was not significantly higher in microgravity. Conclusions We conclude that although tasks are performed with much greater deliberation and work in microgravity, there is no barrier to accurate and effective laparoscopic surgery.

Background: We hypothesized that the Minimally Invasive Surgery Trainer (MIST-VR; VP Medical R, London, U.K.) would be as effective as the Yale Laparoscopic Skills Course in improving laparoscopic intracorporeal suturing skills. Materials and Methods: Each student made six attempts to tie a knot laparoscopically. Students were then randomized to train on the MIST-VR for five sessions (six skills/session) or the Yale Skills for five sessions (three skills/session) over 5 days. On completion of training, all students were evaluated by a test consisting of six attempts to tie a laparoscopic knot. Results: The percentage improvement in knot tying time did not differ significantly in the pelvic trainer group (30 ± 21%) (from 443 ± 135 to 311 ± 137 seconds) and the MIST-VR group (39 ± 21%) (from 409 ± 109 to 256 ± 140 seconds) (P = 0.308). Conclusions: The MIST-VR is equivalent to the Yale Skills Course for training in the advanced laparoscopic skill of intracorporeal suturing.

Two case reports are presented of incarcerated small-bowel internal hernias through mesenteric defects following Roux-en-Y gastric bypass surgery (one case each of open and laparoscopic). Both patients first presented to physicians unfamiliar with bariatric surgery complaining of vague, cramping midabdominal pain, and the correct diagnosis was not revealed until laparoscopic surgery was performed. Treatment then resulted in quick recoveries. This type of hernia can evade radiologic testing. Prompt clinical recognition and treatment is necessary to prevent small-bowel infarction.

We describe a patient with infected pancreatic necrosis who was treated successfully with minimally invasive surgery. Five weeks after an episode of acute uncomplicated pancreatitis, he was found to have infected pancreatic necrosis and splenic vein thrombosis. The patient underwent a laparoscopic pancreatic necrosectomy, splenectomy, and cholecystectomy. Seven days after surgery, the patient was discharged and continued to be asymptomatic for the 6 months of follow-up.