A novel simulation model for minimally invasive spine surgery.

OBJECTIVE: Minimally invasive spine surgery (MISS) is among the fastest growing technologies in general neurosurgical practice. In addition, great demand exists to teach these skills to neurosurgery residents. With newly enforced work hour restrictions, opportunities to acquire these skills are limited, necessitating development of alternative strategies of education. We describe a novel simulation model for MISS supplemented by resident self-assessment analysis and evaluation. METHODS: The simulator was constructed using a nontransparent Plexiglas frame supplemented with a modified halo frame on which to affix spine specimens. Interchangeable copper tubing was affixed to a 360-degree pivot system to replicate a working portal. Deer skulls and spines were then collected and prepared accordingly. Laboratory exercises were based on the resident's level of training with emphasis on proper drilling techniques. Eight neurosurgery residents were asked to complete the exercises and complete a self-assessment survey regarding their competence level on a scale of 0 to 5, both before and after completing the skill sets. Additionally, they were asked to complete an exit survey that was used to assess the simulation exercises. RESULTS: All exercises were completed successfully with the exception of placing 2 separate pedicle screws through the same portal, which posed difficulty on some specimens because of the of lack of lordosis of the specimens, leading to unfavorable trajectories using a free-hand technique. With regard to the resident self-assessment analysis, the mean confidence rating for performing an MISS laminectomy improved by a difference of 1.25 points (n = 8; 95% confidence interval, 0.66-1.84; P = 0.0015), from 2.50 to 3.75 before and after simulation exercises, respectively, and reached statistical significance. For the senior-level residents, the mean confidence rating for performing MISS placement of pedicle screws using a free-hand technique improved by a difference of 1.00 (n = 3; 95% confidence interval, -1.48-3.48; P = 0.225), from 3.33 to 4.33 before and after simulation exercises, respectively. Results of the exit survey were encouraging. CONCLUSION: The MISS simulator is a feasible, inexpensive, and reproducible adjunct to neurosurgery resident training and provides a new teaching method for spine surgery. Further investigation of this technology is warranted, although multicenter, randomized, controlled trials assessing its validity may not be practical because of ethical constraints with regard to patient safety.

Optimizing microsurgical skills with EEG neurofeedback.

BACKGROUND: By enabling individuals to self-regulate their brainwave activity in the field of optimal performance in healthy individuals, neurofeedback has been found to improve cognitive and artistic performance. Here we assessed whether two distinct EEG neurofeedback protocols could develop surgical skill, given the important role this skill plays in medicine. RESULTS: National Health Service trainee ophthalmic microsurgeons (N = 20) were randomly assigned to either Sensory Motor Rhythm-Theta (SMR) or Alpha-Theta (AT) groups, a randomized subset of which were also part of a wait-list 'no-treatment' control group (N = 8). Neurofeedback groups received eight 30-minute sessions of EEG training. Pre-post assessment included a skills lab surgical procedure with timed measures and expert ratings from video-recordings by consultant surgeons, together with state/trait anxiety self-reports. SMR training demonstrated advantages absent in the control group, with improvements in surgical skill according to 1) the expert ratings: overall technique (d = 0.6, p < 0.03) and suture task (d = 0.9, p < 0.02) (judges' intraclass correlation coefficient = 0.85); and 2) with overall time on task (d = 0.5, p = 0.02), while everyday anxiety (trait) decreased (d = 0.5, p < 0.02). Importantly the decrease in surgical task time was strongly associated with SMR EEG training changes (p < 0.01), especially with continued reduction of theta (4-7 Hz) power. AT training produced marginal improvements in technique and overall performance time, which were accompanied by a standard error indicative of large individual differences. Notwithstanding, successful within session elevation of the theta-alpha ratio correlated positively with improvements in overall technique (r = 0.64, p = 0.047). CONCLUSION: SMR-Theta neurofeedback training provided significant improvement in surgical technique whilst considerably reducing time on task by 26%. There was also evidence that AT training marginally reduced total surgery time, despite suboptimal training efficacies. Overall, the data set provides encouraging evidence of optimised learning of a complex medical specialty via neurofeedback training.

Effect of caffeine on microsurgical technical performance.

Microsurgeons may choose to avoid caffeine to prevent potentially deleterious caffeine tremor, although an adverse effect on surgical skill has never been shown. This double-blind placebo-controlled crossover study investigated the effect of moderate caffeine intake on microsurgical ability among microsurgical training course attendees. Subjects were randomized to receive either morning placebo and afternoon caffeine, or the reverse, thereby acting as their own controls. Performance in end-to-end vessel anastomosis was graded by a single observer during both sessions using a global rating scale. Subjects consuming caffeine in the morning demonstrated significantly improved scores from morning to afternoon, whereas subjects consuming caffeine in the afternoon showed no such improvement. These results are consistent with an adverse effect of caffeine on microsurgical skill combined with a learning curve among the study population of novice microsurgeons, and support the view that caffeine has a detrimental effect on microsurgical ability among this study group.