Background and Purpose—Better selection of patients for intravenous recombinant tissue plasminogen activator (IV tPA) treatment may improve clinical outcomes. We examined the cost-effectiveness of adding penumbral-based MRI to usual computed tomography (CT)-based methods to identify patients for IV tPA treatment.

Methods—A decision-analytic model estimated the lifetime costs and outcomes associated with penumbral-based MRI selection in a patient population similar to that enrolled in the IV tPA clinical trials. Inputs were obtained from published literature, clinical trial data, claims databases, and expert opinion. Outcomes included cost per life-year saved and cost per quality-adjusted life-year (QALY) gained. Costs and outcomes were discounted at 3% annually. Sensitivity analyses were conducted.

Results—The addition of penumbral-based MRI selection increased total cost by $103 over the patient's remaining lifetime. Penumbral-based MRI selection resulted in favorable outcomes (modified Rankin Scale 1) more often than CT-based selection (36.66% versus 35.06%) with an incremental cost per life year of $1840 and an incremental cost per QALY of $1004. Multivariate sensitivity analysis predicted cost-effectiveness ($50 000 per QALY) in 99.7% of simulation runs.

Conclusions—Selecting ischemic stroke patients for IV tPA treatment using penumbral-based MRI after routine CT may increase overall acute care costs, but the benefit is large enough to make this highly cost-effective. This economic analysis lends further support to the consideration of a paradigm shift in acute stroke evaluation.