Learning rate for laparoscopic surgical skills on MIST VR, a virtual reality simulator: quality of human-computer interface

Acquiring laparoscopic surgical skills involves initial learning of cogniti ve and motor skills followed by refinement of those skills. The successful use of a virtual reality simulator depends on the quality of the interface for the human-computer interaction and this can be determined by the initia l learning rate. MIST VR, a part-task virtual reality laparoscopic simulato r, provides objective assessment of psychomotor skills and can generate an overall score for performance, based upon errors made and time taken for si x different tasks. This study analysed the rate of early task/instrument/co mputer familiarisation on consecutive scores achieved by surgically experie nced and naive individuals. Eleven surgeons, 18 medical students and seven non-medical personnel were tested on the simulator up to ten consecutive ti mes, within a 2-week period. Performance data from every task and repetitio n were analysed to obtain individual scores of task performance. The calcul ation of overall score penalised errors far more heavily than total time ta ken, with high scores indicating poor performance. The surgeon-computer int erface generated a rapid and significant early familiarisation curve up to the third session on the simulator, with significant reductions in both tim e taken and total contact errors made. These results suggest that MIST VR r epresents a high quality interface. Surgeons scored consistently and signif icantly better than other subjects on all tasks. For surgically naive indiv iduals, it was possible to predict the level of laparoscopic skills perform ance that would be attained after overcoming initial simulator learning cur ve, by studying their initial score. Overall scores reflected surgical expe rience and suggest that the simulator is measuring surgically relevant para meters. MIST VR provides a validated and much needed method for objective a ssessment of laparoscopic skills, for a variety of surgical disciplines.