The Rochester Model for Spinal CSF Leak Repair Simulation and Scoring

Iatrogenic spinal durotomies occur at a rate of 1% to 17%. Surgical simulation for durotomy repair is needed to provide affordable, accessible, and validated practice. This study sought to design and validate a simple 3-dimensional printed model for spinal cerebrospinal fluid (CSF) leak repair and to introduce the Rochester original objective structured assessment of technical skills (OSATS) CSF leak (ROCL) repair criteria for assessment.

A spinal model was designed to mimic a lumbar laminectomy with the L3-5 lamina removed and 3-dimensional printed using Vero polymers. The model was paired with a porcine collagen "dura" that was pressurized using IV saline and overlayed with gel-molded fascial, muscle, and skin layers with an opening. Participants were provided a training model with a 1.5-cm midline durotomy, surgical microinstrument set, microscope, and 6-0 prolene suture. The 25-point ROCL repair criteria were adapted from the original OSATS principles to assess proficiency in surgical repair by 2 blinded neurosurgeons not participating in the trials. Postsimulation survey data regarding model realism were collected.

Six residents and 4 attendings participated. Median operative time in minutes was 13 minutes among residents and 7 minutes among attendings. Moreover, the ROCL score was a median of 19/25 for attendings and 15/25 for residents. The suture angle was statistically more consistent among senior residents and attendings compared with junior residents. Participants agreed that the model was realistic (median 4/5), useful for improving the operative technique (median 5/5), and would increase comfort in spinal CSF leak repair procedures (median 5/5). Each reusable model had a cost of $19.99 if printed with polylactic acid and each replacement dura cost <3¢.

This study presents an affordable, realistic, and educational spinal CSF leak repair model and introduces ROCL for assessment.