Optimal imaging follow-up strategies for conservatively managed cerebral cavernous malformations: a cost-effectiveness analysis.

Abstract

Cavernous malformations are low-flow vascular anomalies within the central nervous system, notable for their potential to cause seizures or intraparenchymal hemorrhage. Currently, no consensus exists to recommend a specific interval for following radiographic imaging of cerebral cavernous malformations (CCMs) that are not treated with either resection or radiation. Herein, the authors aimed to determine the most cost-effective strategy for MRI follow-up of CCM in both brainstem and nonbrainstem locations in order to enable earlier diagnosis and potentially circumvent fatal events due to CCM-related hemorrhages. A decision analysis was performed using a Markov model with Monte Carlo simulations for patients with CCMs undergoing MRI follow-up at different time intervals (0.5-, 1-, 2-, and 3-year intervals). Input data for the model were extracted from the current literature, primarily meta-analyses, and the willingness-to-pay threshold was defined as $50,000 per quality-adjusted life year (QALY), as standard in the United States. Probabilistic and deterministic sensitivity analyses were performed to evaluate the robustness of the model. Given the current literature and the authors' model, MRI follow-up every 1 year for brainstem CCM is the most cost-effective strategy (cost $395,580, effectiveness 20.42 QALYs), showing the highest net monetary benefit. For nonbrainstem CCM, follow-up every 3 years with MRI was the most cost-effective strategy (cost $125,438, effectiveness 23.23 QALYs). This conclusion remains robust in probabilistic and deterministic sensitivity analyses. For patients followed conservatively, the most cost-effective follow-up strategy for brainstem CCM using MRI is every 1 year, while for nonbrainstem CCM, follow-up every 3 years tends to be the most cost-effective. More frequent follow-up strategies for nonbrainstem CCM or prompt preventive treatment would be more appropriate in symptomatic patients or patients with higher risk factors for hemorrhagic events.