Trends in Resident Operative Teaching Opportunities for Treatment of Intracranial Aneurysms

Objective: The International Subarachnoid Aneurysm Trial heralded a paradigm shift in the treatment of intracranial aneurysms. During this same time frame, neurosurgical training programs increased in size and scope. The present study examines the impact of trends in surgical clipping and the endovascular treatment of intracranial aneurysms, over one decade, and the neurosurgical resident complement on the resident teaching environment using the Nationwide Inpatient Sample (NIS).

Methods: The NIS was used to estimate the number of aneurysms treated with either surgical clipping and endovascular methods from 2002 through 2011 at teaching institutions. Teaching opportunities per year per resident or chief resident were calculated as the ratio of the number of specified cases to the average number of neurosurgical trainees by year. Annualized trends were assessed.

Results: Over the study period, the percent change in odds of occurrence of a clipped ruptured aneurysm was -15.6% per year (P < 0.001) and of ruptured aneurysms undergoing endovascular treatment was 18.7% per year (P < 0.001) within teaching institutions. This corresponded to a decline in teaching opportunities for clipped ruptured aneurysms for both residents and chief residents (P < 0.001). In contrast, teaching opportunities for endovascular treatment of both ruptured and unruptured aneurysms increased dramatically over the study period.

Conclusions: There has been a significant decrease in opportunity for operative exposure to craniotomy for ruptured aneurysm clipping over the past decade, whereas the volume of endovascular procedures for aneurysms has dramatically increased, highlighting the need for a shift in training strategy for those neurosurgeons graduating from residency desiring to subspecialize in neurovascular neurosurgery.