Marshall Smith

A multicenter review of 839 laparoscopic-assisted vaginal hysterectomies

A multicenter review of 839 cases of laparoscopic-assisted vaginal hysterectomy (LAVH) was conducted to contribute to the clinical decision-making process regarding the procedure, which has been the subject of much debate in recent years. The results suggest that patients undergoing LAVH experience complication rates no higher than those having any other type of hysterectomy, and that efficacy is identical to that of vaginal hysterectomy. Furthermore, the laparoscopic approach affords better visualization of pelvic pathology and better adnexal access for the accomplishment of concurrent pelvic procedures. Mean hospital stay is 1.7 days and mean recovery time 20 days. The notion of a learning curve as described by diminishing procedure time and declining complication rates over time is not supported by this data set. Patients who may traditionally have faced abdominal hysterectomy due to putative or demonstrated pelvic pathology may benefit the most from LAVH.

Measuring movement expertise in surgical tasks

Surgical movement is composed of discrete gestures that are combined to perform complex surgical procedures. A promising approach to objective surgical skill evaluation systems is kinematics and kinetic analysis of hand movement that yields a gesture level analysis of proficiency of a performed movement. In this paper, we propose a novel system that combines surgical gesture segmentation, surgical gesture recognition, and expertise analysis of surgical profiles in minimally invasive surgery (MIS). Kinematic analysis was used to segment gestures from a continuous motion stream. Human anatomy driven Hidden Markov Models (HMMs) are adopted for gesture recognition and expertise identification. When the proposed system was tested on a library of 200 samples for every basic surgical gesture, the gesture recognition module reported a perfect accuracy rate for the basic gestures, while the expertise identification module showed 94.7% accuracy.

Quantitative Evaluation of Retention of Surgical Skills Learned in Simulation

BACKGROUND While initial results suggest that simulation does promote learning, there is a dearth of studies that define the extent to which skills learned through simulation are retained. METHODS Residents skills were measured upon completion of an initial simulation training (baseline scores) and then every month for 6 months. Analysis was also performed to identify the number of iterations of practice required to regain baseline scores. RESULTS While skill scores did not deteriorate from baseline after the first 3 months (p = 0.61, p = 0.44, p = 0.2, respectively), all scores (except time elapsed) reflected significant deterioration from the fourth month onward (p < 0.05, p < 0.032, p < 0.02). However the number of practice sessions required to regain baseline scores was significantly less than that required to achieve the baseline skill set (p < 0.0003). CONCLUSIONS Skills learned through simulation show significant deterioration over long periods of time, suggesting that periodic retraining of skills may be necessary to maintain surgical proficiency.

Distractions and surgical proficiency: an educational perspective

BACKGROUND Surgery training requires residents to focus on tasks while minimizing the effect of distractions. There is a need to develop training methodologies that can enable surgical residents to hone this ability. METHODS Fourteen surgical residents were divided into 2 groups. They were trained to perform simulated tasks in a noiseless environment and subsequently performed these tasks in a distractive one. In a follow-up experiment, an experimental group was trained in noisy and distractive conditions and was compared with a control group trained in noiseless conditions. RESULTS Residents who trained in noiseless environments possessed decreased surgical proficiency when performing the identical tasks in realistic environments (P < .05). Pretraining in a noisy environment improves surgical proficiency. CONCLUSIONS Noise and distractions can significantly impede performance of surgical residents, but this effect can be nullified by introduction of noise and distractions in the training environment.

Virtual reality based training to resolve visio-motor conflicts in surgical environments

An issue that complicates movement training, specifically in minimally invasive surgery, is that often there is no one to one correlation between the visual feedback provided on a screen and the movement required to perform the given task. This paper presents a simulator that specifically addresses the intermodal conflict between motor actuation and visual feedback. We developed a virtual reality visio-haptic simulator to assist surgical residents in training to resolve visio-motor conflict. The developed simulator offers individuals the flexibility to train in various scenarios with different levels of visio-motor conflicts. The levels of conflict were simulated by creating a linear functional relation between movement in the real environment and the virtual environment. The haptic rendering was consistent with the visual feedback. Experiments were conducted with expert pediatric surgeons and general surgery residents. Baseline data on performance in conditions of visio-motor conflict were assimilated from expert surgeons. Residents were divided into experimental group that was exposed to visio-motor conflict and the control group which wasnpsilat exposed to visio-motor conflict training. When the performance was compared on a standard surgical suturing task, the residents with inter-modal conflict training performed better than the control group suggesting the construct validity of the training and that visio-motor training can accelerate learning.

Honing a surgeon's decision making skills in the presence of mechanical tasks

BACKGROUND Although surgeons perform procedures and tasks under a significant amount of cognitive load, current simulators focus on training psychomotor skills in isolation. This may limit the transfer of learned skills to actual surgical environments. METHODS Visuohaptic simulations were created that required participants to hone psychomotor skills in the presence of cognitive load. A control group (n = 7) trained on conventional skills simulator and their performance was compared with the experimental group (n = 7) in terms of learning curves and performance on a transfer task. RESULTS The experimental group performed significantly better than the control group in terms of both learning curves and performance on the transfer task. CONCLUSIONS Simulations that combine psychomotor and cognitive skills training are more effective than simulators that focus on psychomotor skills in isolation.