Vivek Datta

The use of electromagnetic motion tracking analysis to objectively measure open surgical skill in the laboratory-based model.

BACKGROUND Technical performance has traditionally been assessed subjectively within the operating theater, with few successful attempts at objective analysis. The Imperial College Surgical Assessment Device (ICSAD) has already been shown to be a valid quantitative measure of dexterity in laparoscopic surgical simulation. We describe its application to the assessment of open surgical procedures. STUDY DESIGN Fifty-one participants were recruited from four different levels of general surgical experience: basic surgical trainees (n = 12), junior specialist registrars (n = 13), senior specialist registrars (n = 13), and consultants (n = 13). They completed two tasks: a small bowel anastomosis and a vein patch insertion into an artery. Surgical performance was measured with the Imperial College Surgical Assessment Device, a motion analysis system that measures the number of hand movements made and time taken to complete a task. The four groups were compared statistically using the Kruskal-Wallis test (K-W). Pairwise group comparisons used the Mann-Whitney U test and p values were adjusted for multiple comparisons to determine the statistical significance of these comparisons. RESULTS Mean values for number of movements and time (secs) for small bowel anastomosis were 2,080/1,236 (basic surgical trainees), 1,673/1,016 (junior specialist registrars), 1,375/862 (senior specialist registrars), and 1,337/782 (consultants), respectively. Comparison of the medians by K-W revealed a p < 0.001 for each variable (No. of movements, time), respectively. Mean vein patch insertion results were 1,653/1,258, 1,297/1,006, 1,090/912, and 925/736 for each of the four groups. Again, comparison of the medians by K-W revealed a p < 0.001 for each variable. CONCLUSIONS These findings suggest that hand motion analysis may be an effective objective measure of dexterity in open surgical simulation.

Practice distribution in procedural skills training: a randomized controlled trial.

Background“Massed” and “distributed” practice are important concepts in the acquisition of fine motor skills, and may be important in training in procedural skills.MethodsA total of 41 novice subjects were recruited and randomized to three groups to receive training on the MIST VR surgical trainer. There were 14 subjects in each of groups A and B and 13 subjects in group C. Training comprised 20 min of massed practice for group A, 20 min of distributed practice in 5 min blocks for group B, and 15 min of distributed practice in 5-min blocks for group C. Following the training period, all groups had a 5-min rest period, followed by a 5-min retention test. Comparisons were made between groups A and B, and groups A and C.ResultsThere was a statistically significant difference between groups A and B (p= 0.023) on the retention test, with group B performing better. The increment between the groups was 19% for the overall score on MIST VR. There were also significant differences in the time taken to complete the task during the training phase (p=0.023, training blocks 3 and 4). Graphical representation suggests no effect between groups A and C, and statistical analysis confirms that the observed difference in median score is not significant.ConclusionThis study demonstrates a benefit for distributed practice over massed practice in learning laparoscopic surgical skills on the MIST VR surgical trainer. This finding has potential implications for skills training in all areas of medicine.

The challenge of objective assessment of surgical skill

Technical performance in surgery has come under increased scrutiny in recent years, not least due to several highly publicized cases where it has been suggested that poor outcomes were the result of inadequate technical skill [1–3]. In the Bristol case, which involved a pediatric cardiac surgery unit, the concerns voiced by a member of medical staff have now resulted in disciplinary action against two surgeons by the General Medical Council, and a judicial inquiry, which is yet to hand down its report (www.bristol-inquiry.org.uk). The resulting debate, both public and within the profession, has focused on the need for objective and independent assessment of surgical skill, and a significant research interest has developed in this area.

The PreOp flexible sigmoidoscopy trainer

AIM: To demonstrate face and construct validity of a computer based flexible sigmoidoscopy trainer. METHODS: The PreOp (Immersion Medical, USA) system is a virtual reality based flexible sigmoidoscopy simulator. The system records several performance parameters, such as percentage of colonic mucosa visualized, time taken, and pathlength of endoscope travel. Forty-five subjects were divided into three groups: novice (never performed a lower GI endoscopy), intermediate (5–50 examinations), and trained (greater than 200 examinations). After initial familiarization subjects were assessed three times on a case module. Results showed a nonparametric distribution. RESULTS: There was a significant difference between all three groups with respect to percentage of mucosa visualized (novice 71.0 ± 3.7%, intermediate 77.3 ± 5.6%, expert 84.8 ± 4.6%, Kruskal–Wallis p <0.001) and efficiency ratio (%mucosa/time, novice 0.163 ± 0.055, intermediate 0.259 ± 0.07, expert 0.306 ± 0.058, p <0.001). The novice group was also slower and had a lower pathlength of instrument travel compared to the others. CONCLUSION: PreOp virtual reality simulator is a valid discriminator of flexible sigmoidoscopic experience. Its effect on training needs to be explored.

Multiple Objective Measures of Skill (moms): A New Approach to the Assessment of Technical Ability in Surgical Trainees

Objective The assessment of surgical technical skills has become an important topic in recent years. This study presents the validation of a 6-task skills examination for junior surgical trainees (at the level of the Membership of the Royal College of Surgeons). Summary Background Data Six tasks were evaluated in a project that also examined the feasibility of this method of assessment. The tasks were knowledge of sutures and instruments; knowledge of surgical devices; knot formation; skin-pad suturing, closure of an enterotomy; excision of a skin lesion; and laparoscopic manipulation. Comparisons were made between a group of junior trainees (n = 13), and a group of seniors (n = 8). Results Each of the 6 tasks was able to be used to discriminate between the 2 groups. In all, there were 19 primary analyses across the 6 tasks, and 17 of these showed significant differences between the groups (P values ranging from 0.037 to < 0.001). There was generally a strong correlation between the analyses, and when a mean rank was calculated, the difference between groups was significant (P = 0.005 on Mann–Whitney U test; mean ranks 13.9 and 6.3 [of 21], for juniors and seniors respectively). Reliability of the 6-task assessment was very good at 0.70 (Cronbachs Alpha). Conclusions A skills examination is a feasible and effective method of assessing the technical ability of basic surgical trainees.

Robotics in surgery

The drive to introduce operating robots into theaters is for a number of reasons related to their intrinsic properties: these include three-dimensional spatial accuracy, reliability, and precision, and in minimal-access surgery they aid the surgeon, who must contend with deficits in sensation and dexterity. There are a number of robots already in clinical use, in neurosurgery and orthopaedics, that possess these traits and can be used once the area to be removed or biopsied has been highlighted. In one particular area there has been a rapid expansion in the commissioning and use of surgical robots: that of the telemanipulators. The introduction of the telemanipulators in minimal-access surgery has restored the loss of dexterity and visual quality that is inherent in minimalaccess surgery, allowing for more complex procedures to be undertaken with a high degree of quality. This article will consider the history of robots in surgery and their current use with particular reference to these systems. The robot has been defined as “a reprogrammable multifunctional manipulator designed to move material, parts, tools, or specialized devices through variable programmed motions for the performance of a variety of tasks” by the Robot Institute of America. Webster defines them as “an automated device that performs functions normally ascribed to humans or a machine in the form of a human.” The term robotics refers to the study and use of robots. The word robot was first introduced in Karel Capek’s play “Rossum’s Universal Robots,” which opened in Prague in 1921. This play concerned the dehumanization of man in a technological civilization, and the robots were created by chemical rather than mechanical means. The word robotics refers to the study and use of robots and was first used by Isaac Asimov in his short story “Runaround”, later proposing the Laws of Robotics (Table 1). His laws refer to the protection of humanity above humans, that robots must obey humans unless it conflicts with a higher law. These principles of safety, initially raised by Asimov, will be considered later, especially with reference to public education. The first industrial robots were the Unimates developed by George Devol and Joe Engelberger in the late 1950s and early 1960s. The robotics industry expanded rapidly in the 1980s with their use in production lines of the automotive industry, followed by a relative collapse and recent regrowth of the industry. The move of robots into surgery has occurred in the last twenty years with a recent rapid expansion related to cost and computing power. There is an important distinction to be made between computer aided surgery (CAS) and robotic surgery. In CAS, the surgeon generally holds the tools and computers might help in planning and positioning, but in robotic surgery, robots will hold tools, providing greater accuracy and precision. The majority of these computer-based systems are tracking systems, tracking a tool or a part of the anatomy. The tracking system can be sensor-based—eg, light-emitting diodes or optical reflectors mounted on the tool—or if anatomy is being tracked, then three-dimensional modelling by radiographic means will be required. These anatomic reference maps require either obvious anatomical markers or artificial markers known as fiducials. The power for the tools comes from the surgeon. Obviously, there must be careful preoperative planning and the preoperative images of the patient must accurately match the intraoperative position of the patient. The use of robots in medicine can be broadly divided into rehabilitation, service, and surgery (including ancillary devices such as microscopes). Their use in rehabilitation and for assisting disNo competing interests declared.

Electromagnetic motion analysis in the assessment of surgical skill: Relationship between time and movement

Introduction:  Electromagnetic motion analysis is a promising method of assessing surgical skill in a skills‐laboratory setting. There is a very strong correlation between movement and time data, and this study was conducted to determine whether this relationship is fixed, or whether it can vary.

Technical performance: Relation between surgical dexterity and technical knowledge

Technical performance consists of surgical knowledge, judgment, and dexterity. Although assessment of surgical dexterity is now possible, assessing technical knowledge and its relation to dexterity has not been elucidated. Surgeons of varying experience were recruited to the skills laboratory to undertake three assessments: simple surgical dexterity (at 14 stations scored by motion analysis), an operating room equipment examination, and a novel error analysis. The scores were correlated, and p < 0.05 was deemed to be significant. Thirty surgeons were recruited; and construct validity was exhibited in all areas. Correlations were shown to exist between the two knowledge examinations (Spearman’s rho = 039). Correlations existed between all dexterity task parameters and the equipment examination, whereas they existed for only 15 of the 28 parameters of the error examination and were always weaker. The stronger correlations between dexterity and instrument and operating room (OR) equipment reflect greater surgical experience and time spent in the OR. The weaker correlations between the error analysis and dexterity suggest that these skills are learned at different times. The identification of common surgical errors should be more formally taught to ensure greater uniformity.RésuméLes performances techniques comportent des éléments de connaissances chirurgicales, du jugement et de dextérité. Alors que l’évaluation de la dextérité chirurgicale est actuellement possible, celle des connaissances techniques et son rapport avec la dextérité n’ont pas encore été élucidés. Des chirurgiens, d’expérience variée, ont entrepris trois évaluations séparées en laboratoire de dextérité: dextérité chirurgicale simple (14 stations comportant un score par analyse des mouvements), un examen portant sur l’équipement opératoire et une analyse d’erreurs. On a corrélé les scores réalisés entre eux. Une valeur p = 0.05 a été considérée comme significative. 30 chirurgiens ont été recrutés et une validité de construction a été retrouvée dans tous les domaines. On a montré une corrélation entre les deux investigations explorant les connaissances (coefficient de Spearman’s rho = 0.39). On a mis en évidence une corrélation entre tous les paramètres de dextérité et l’examen concernant l’équipement, alors que cette corrélation n’existait que pour 15 des 28 paramètres dans l’analyse des erreurs et le coefficient de corrélation a toujours été moins élevé. Les corrélations les plus fortes entre la dextérité et l’analyse de l’équipement de la salle d’opération reflètent une expérience chirurgicale plus importante et un temps passé en salle d’opération plus long. Les corrélations plus faibles entre l’analyse d’erreur et la dextérité suggèrent que l’adresse des gestes est acquise à des moments différents. L’identification des erreurs les plus fréquentes devrait être formalisée pour assurer une meilleure uniformisation de la formation.ResumenEl desempeño técnico quirúrgico depende del conocimiento, el juicio y la destreza. En tanto que la evaluación de la destreza hoy es factible, la evaluación del conocimiento técnico y su relación con la destreza todavía no ha sido elucidada. Se incluyeron cirujanos con diversos grados de experiencia para realizar 3 tipos de evaluación en el laboratorio de habilidades quirúrgicas: destreza quirúrgica simple (más de 4 estaciones, evaluadas por análisis de movimiento), un examen de equipo de salas de cirugía y un análisis de error novel. Se hizo la correlación de los resultados, dando valor significativo a una p de 0.05. Se incluyó un total de 30 cirujanos y se registró la validez de construcción en todas las áreas. Se demostró la existencia de correlaciones en 2 exámenes de conocimiento (rho = 039 de Spearman). Aparecieron correlaciones entre todos los parámétras de tareas de destreza y los exámenes de equipo, pero sólo apareció en 15 de los 28 parámetras del examen de error y éstas fueron consistentemente más débiles. Las más fuertes correlaciones entre la destreza y el instrumente y el equipo de salas de cirugia reflejan mayor experiencia quirurgica y mayor tiempo de trabajo en las salas de cirugía. Las débiles correlaciones entre el análisis de error y la destreza sugieren que estas habilidades pueden ser adquiridas en diferentes épocas. La identificatión de errores quirúrgicos comunes debería ser ensenada de manera más formal con el fin de lograr una mayor uniformidad.