Neuroimaging Analyses
Baseline multimodal imaging was automatically processed on a dedicated site computer, generating a 4-digit code that assigned patients to treatment on the basis of separate permuted-block sequences for favorable penumbral and nonpenumbral patterns. If local postprocessing failed, the software generated a different 4-digit code indicating that penumbral status was unknown, and the patient underwent randomization with the use of an unknown-pattern permuted-block sequence. Final baseline imaging-pattern assignment was determined by the central imaging laboratory after quality checks and image postprocessing.