Metrics for Evaluating Surgical Microscope Usage During Myringotomy

Abstract Although teaching and learning surgical microscope manoeuvring is a fundamental step in middle ear surgical training, currently there is no objective method to teach or assess this skill. This thesis presents an experimental study designed to implement and test sets of metrics capable of numerically evaluating microscope manoeuvrability and qualitatively assessing surgical expertise of a subject during a middle ear surgery called myringotomy. The experiment involved performing a myringotomy on a fixed cadaveric ear. As participants, experienced ear-nose-throat (ENT) surgeons and ENT surgical residents were invited. While performing the procedure, their microscope manoeuvring motions were captured as translational and angular coordinates using an optical tracker. These data were analyzed in terms of motion path length, velocity, acceleration, jitter, manoeuvring volume, smoothness, rotation and time. Participants’ hand motion, body posture and microscopic view were also video recorded to qualitatively assess their surgical expertise. Several metrics were statistically identified as discriminatory. These metrics will be incorporated into a myringotomy surgical simulator to train ENT residents

ROBOTIC TELESURGERY: AN INVESTIGATION OF UTILITY, HUMAN ADAPTATION, AND PERFORMANCE

Robotic surgery is a powerful, new method for performing minimally invasive surgery (MIS). The method allows complex procedures through incisions which are 10 mm or less. Robotic surgery has grown rapidly because small MIS incisions result in rapid patient recovery compared to conventional methods. Although surgical robots have the potential of long distance control, insufficient data is available to determine whether long distance robotic surgery, or telesurgery, is practical. Telesurgery could provide multiple benefits, including dissemination of expertise, widespread patient care, cost savings, and improved community care. We describe a series of experiments to investigate telesurgery using a one of a kind telesurgery platform and ground- and satellite-based Internet networks. The networks provided the redundancy and quality of service that would be required for human surgery. Tolerances for performing surgical tasks over a long distance were unknown. We show that operators using the platform can complete dry lab manoeuvres with communication latencies up to 500 ms, with no appreciable increase in error rates. Such latency would be equivalent to a North American transcontinental distance, implying a wide range of telesurgical capability. The characteristics of ground- and satellite-based Internet networks for telesurgery were unavailable. We demonstrate that emulated surgery in animals can be effectively performed using either ground or satellite. The networks can reliably support surgery, and satellite-based surgery can be performed even though latency exceeds 500 ms. Further, satellite bandwidth should be above 5 Mb/s for telesurgery applications. Satellite networks could be used either for back up or primarily where a community does not have ground-based equipment. iii Methods of training operators for telesurgery had not been explored. We demonstrate two methods of training for telesurgery. Operators doing dry lab surgical manoeuvres performed equally well either with sequentially increasing latency or with full latency only, suggesting that both methods of training may be effective. Telesurgery can become a practical method of treatment. Within a few years, more widespread platforms and telecommunications may exist to launch everyday telesurgery procedures

A Novel Haptic Simulator for Evaluating and Training Salient Force-Based Skills for Laparoscopic Surgery

Laparoscopic surgery has evolved from an \u27alternative\u27 surgical technique to currently being considered as a mainstream surgical technique. However, learning this complex technique holds unique challenges to novice surgeons due to their \u27distance\u27 from the surgical site. One of the main challenges in acquiring laparoscopic skills is the acquisition of force-based or haptic skills. The neglect of popular training methods (e.g., the Fundamentals of Laparoscopic Surgery, i.e. FLS, curriculum) in addressing this aspect of skills training has led many medical skills professionals to research new, efficient methods for haptic skills training. The overarching goal of this research was to demonstrate that a set of simple, simulator-based haptic exercises can be developed and used to train users for skilled application of forces with surgical tools. A set of salient or core haptic skills that underlie proficient laparoscopic surgery were identified, based on published time-motion studies. Low-cost, computer-based haptic training simulators were prototyped to simulate each of the identified salient haptic skills. All simulators were tested for construct validity by comparing surgeons\u27 performance on the simulators with the performance of novices with no previous laparoscopic experience. An integrated, \u27core haptic skills\u27 simulator capable of rendering the three validated haptic skills was built. To examine the efficacy of this novel salient haptic skills training simulator, novice participants were tested for training improvements in a detailed study. Results from the study demonstrated that simulator training enabled users to significantly improve force application for all three haptic tasks. Research outcomes from this project could greatly influence surgical skills simulator design, resulting in more efficient training

Validation of the Haptic Cow: A simulator for training veterinary students

A virtual reality simulator, the Haptic Cow, has been developed using touch feedback technology for training veterinary students to perform bovine rectal palpation of the reproductive tract. The simulator was designed to supplement existing training and address some of the difficulties associated with teaching palpation-based skills. Students need to achieve a certain level of proficiency by graduation but this has become increasingly difficult because of problems with current training methods and a reduction in the number of opportunities to practice. A simulator- based teaching tool was developed as a potential solution. The first step involved designing a simulator on the basis of requirements established through consultation with both veterinary surgeons, as teachers, and students, as learners. Research was then undertaken to validate the simulator by following a set of established criteria described for the evaluation of new technologies used in medical education. The virtual models were assessed by experts as realistic enough representations of the same structures in the cow. An experiment to assess the effect of simulator training compared the performance of one group of students, whose training was supplemented with a simulator session, with another group of traditionally trained students. The subsequent performance for finding and identifying the uterus when examining cows for the first time, was significantly better for the simulator trained group, indicating that skills learned in the simulator environment transferred to the real task. A project was also undertaken to integrate the simulator into a curriculum, with training included as part of the farm animal course at the University of Glasgow Veterinary School. The training was well received by students, useful feedback was gathered and the simulator continues to be used as part of the course. Further developments were undertaken with the aim of creating a more versatile teaching tool and addressing some of the questions and issues raised. An automated version of the Haptic Cow was designed for students to use on their own, with computer guidance replacing the instructor's role. An evaluation found that the new version of the teaching tool was both usable and an effective way of equipping students with the skills required to find and identify the uterus. The potential to use haptic technology to investigate various aspects of performance was also explored in relation to the question of hand choice for certain palpation-based skills: differentiating between objects on the basis of softness and size. Ongoing research and development options are discussed, with the aim of building on the current work by expanding the role of haptic technology in veterinary education in the future