Referral of Pediatric Moyamoya for Revascularization: Financial and Quality Data Supporting Private Insurer Approval for Out-of-Network Care.

Background: Moyamoya is a rare arteriopathy affecting the intracranial circulation with a risk of stroke in the pediatric population. High-volume centers provide improved outcomes after surgical revascularization compared with low-volume centers. However, private insurers are often reluctant to approve care out-of-network. We hypothesized that rare diseases that can be treated in a single procedure, such as revascularization for moyamoya, can yield improved clinical outcomes with substantial cost savings to insurance companies when approved for care at high-volume centers of excellence. Methods: Longitudinal deidentified data of pediatric patients undergoing surgical revascularization for moyamoya from January 2018 to December 2020 (N = 125) were obtained from national commercial insurers by an independent third-party analytics core. Patients were selected according to International Classification of Diseases, Tenth Revision (ICD-10) diagnosis and procedure codes. For a 9-month episode, clinical and cost outcome metrics were compared across centers, with patients from the highest volume center designated as the primary cohort. Results: Patients in the primary cohort were on average younger at time of surgery, with greater medical comorbidities, yet exhibited decreased postoperative complications and fewer unplanned readmissions. The primary cohort had an overall 42% lower expense compared with patients treated at other single institution health systems ($89 000 versus $153 000). The primary cohort minimized out-of-network costs with implementation of a partnership care model, using local resources for preoperative workup in 68% of episodes, compared with only 8% of episodes at a comparator high-volume center. Conclusion: Implementation of a partnership model takes advantages of the surgical resources of a high-volume center while maximizing local resource use for preoperative and postoperative care. Referral to high-volume centers for pediatric moyamoya revascularization provides both improved outcomes for the patients and substantial cost savings for the insurers. These data suggest the development of high-volume centers of excellence for select conditions requiring neurosurgical treatment confer benefit to both patients and insurers, even in cases of out-of-network care.