Gabel, Brandon

OBJECTIVEThe subspecialization of neurosurgical practice is an ongoing trend in modern neurosurgery. However, it remains unclear whether the degree of surgeon specialization is associated with improved patient outcomes. The authors hypothesized that a trend toward increased neurosurgeon specialization was associated with improved patient morbidity and mortality rates.METHODSThe Nationwide Inpatient Sample (NIS) was used (1998–2009). Patients were included in a spinal analysis cohort for instrumented spine surgery involving the cervical spine (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] codes 81.31–81.33, 81.01–81.03, 84.61–84.62, and 84.66) or lumbar spine (codes 81.04–81.08, 81.34–81.38, 84.64–84.65, and 84.68). A cranial analysis cohort consisted of patients receiving a parenchymal excision or lobectomy operation (codes 01.53 and 01.59). Surgeon specialization was measured using unique surgeon identifiers in the NIS and defined as the proportion of a surgeon’s total practice dedicated to cranial or spinal cases.RESULTSA total of 46,029 and 231,875 patients were identified in the cranial and spinal analysis cohorts, respectively. On multivariate analysis in the cranial analysis cohort (after controlling for overall surgeon volume, patient demographic data/comorbidities, hospital characteristics, and admitting source), each percentage-point increase in a surgeon’s cranial specialization (that is, the proportion of cranial cases) was associated with a 0.0060 reduction in the log odds of patient mortality (95% CI 0.0034–0.0086) and a 0.0042 reduction in the log odds of morbidity (95% CI 0.0032–0.0052). This resulted in a 15% difference in the predicted probability of mortality for neurosurgeons at the 75th versus the 25th percentile of cranial specialization. In the spinal analysis cohort, each percentage-point increase in a surgeon’s spinal specialization was associated with a 0.0122 reduction in the log odds of mortality (95% CI 0.0074–0.0170) and a 0.0058 reduction in the log odds of morbidity (95% CI 0.0049–0.0067). This resulted in a 26.8% difference in the predicted probability of mortality for neurosurgeons at the 75th versus the 25th percentile of spinal specialization.CONCLUSIONSFor both spinal and cranial surgery patient cohorts derived from the NIS database, increased surgeon specialization was significantly and independently associated with improved mortality and morbidity rates, even after controlling for overall case volume.

Study Design: Retrospective multicenter case series. Objective: To assess the rate of perioperative vision loss following cervical spinal surgery. Methods: Medical records for 17 625 patients from 21 high-volume surgical centers from the AOSpine North America Clinical Research Network who received cervical spine surgery (levels from C2 to C7) between January 1, 2005, and December 31, 2011, inclusive, were reviewed to identify occurrences of vision loss following surgery. Results: Of the 17 625 patients in the registry, there were 13 946 patients assessed for the complication of blindness. There were 9591 cases that involved only anterior surgical approaches; the remaining 4355 cases were posterior and/or circumferential fusions. There were no cases of blindness or vision loss in the postoperative period reported during the sampling period. Conclusions: Perioperative vision loss following cervical spinal surgery is exceedingly rare.