Regional Disparities in Trends of Medicare Reimbursements and Service Volumes for Stereotactic Radiosurgery Among Neurosurgeons and Radiation Oncologists: 2014-2022

Introduction: Stereotactic radiosurgery (SRS) is widely used in the definitive and post-operative management of intracranial neoplasms, particularly brain metastases. Despite the frequent collaboration between neurosurgeons and radiation oncologists in delivering SRS, geographic variations in reimbursement rates and the extent of neurosurgical involvement are not well understood.

Methods: To compare baseline SRS treatment costs between neurosurgeons and radiation oncologists, Medicare physician fee schedules were analyzed for inflation-adjusted reimbursement rates by locality, using CPT codes 61796 (SRS for a simple cranial lesion, neurosurgery) and 77372 (SRS for a single session, radiation oncology [RO]) from 2014 to 2022. State-level service volumes for CPT codes 61796, 61798 (SRS for a complex lesion, neurosurgery), 77432 (SRS management for a single session, RO), and 77435 (SRS management for multiple sessions, RO) were extracted from Medicare Public Use Files. Reimbursement rates and service volumes were averaged by state and analyzed across U.S. Census Regions (Northeast, Midwest, South, West). Multivariate linear regression evaluated trends by region, specialty, and year.

Results: Between 2014 and 2022, the average SRS reimbursement declined by $35.05 per year (from $1,291.65 to $1,012.96, P < 0.001). Physicians in the Midwest received lower average reimbursements ($1,125.27) compared to the Northeast ($1,256.72, P < 0.001), West ($1,215.05, P < 0.001), and South ($1,150.58, P < 0.05). Radiation oncologists were reimbursed more than neurosurgeons ($1,200.80 vs. $1,173.02, P < 0.001). Nationally, SRS treatment volumes increased from 30,392 to 53,700 (P < 0.001), while neurosurgical involvement in SRS decreased from 31.44% to 16.41% of all cases (P < 0.001). Neurosurgical participation in SRS was highest in the Northeast (26.12%), West (24.20%), and South (21.95%) compared to the Midwest (20.13%) (all P < 0.001).

Conclusion : Significant regional disparities exist in SRS reimbursement rates and neurosurgical involvement. Addressing these disparities may promote more equitable access to neuro-oncological care across the U.S.