Longitudinal survey of cranial case log entries during neurological surgery residency training

The purpose of this study was to analyze national trends in adult cranial cases performed by neurological surgery residents as logged into the Accreditation Council for Graduate Medical Education (ACGME) system.

The ACGME resident case logs were retrospectively reviewed for the years 2009-2017. In these reports, the national average of cases performed by graduating residents is organized by year, type of procedure, and level of resident. These logs were analyzed in order to evaluate trends in residency experience with adult cranial procedures. The reported number of cranial procedures was compared to the ACGME neurosurgical minimum requirements for each surgical category. A linear regression analysis was conducted in order to identify changes in the average number of procedures performed by residents graduating during the study period. Additionally, a 1-sample t-test was performed to compare reported case volumes to the ACGME required minimums.

An average of 577 total cranial procedures were performed throughout residency training for each of the 1631 residents graduating between 2009 and 2017. The total caseload for graduating residents upon completion of training increased by an average of 26.59 cases each year (r2 = 0.99). Additionally, caseloads in most major procedural subspecialty categories increased; this excludes open vascular and extracranial vascular categories, which showed, respectively, a decrease and no change. The majority of cranial procedures performed throughout residency pertained to tumor (mean 158.38 operations), trauma (mean 102.17 operations), and CSF diversion (mean 76.12 operations). Cranial procedures pertaining to the subspecialties of trauma and functional neurosurgery showed the greatest rise in total procedures, increasing at 8.23 (r2 = 0.91) and 6.44 (r2 = 0.95) procedures per graduating year, respectively.

Neurosurgical residents reported increasing case volumes for most cranial procedures between 2009 and 2017. This increase was observed despite work hour limitations set forth in 2003 and 2011. Of note, an inverse relationship between open vascular and endovascular procedures was observed, with a decrease in open vascular procedures and an increase in endovascular procedures performed during the study period. When compared to the ACGME required minimums, neurosurgery residents gained much more exposure to cranial procedures than was expected. Additionally, a larger caseload throughout training suggests that residents are graduating with greater competency and experience in cranial neurosurgery.