Restoration of the ascending reticular activating system compressed by hematoma in a stroke patient

RATIONALE: We report on restoration of the ascending reticular activating system (ARAS), compressed by an intracerebral hematoma and perihematomal edema following a stroke. The restoration of the ARAS was demonstrated by diffusion tensor tractography (DTT). PATIENT CONCERNS: In a 60-year-old male, a brain MRI taken at 2 weeks after the surgery showed a hematoma and perihematomal edema in the left posterolateral pons and cerebellum, which were markedly resolved on a brain MRI after 5 weeks. DIAGNOSES: Intraventricular hemorrhage. INTERVENTIONS: Navigation-guided stereotactic drainage of a hematoma in the left cerebellum, comprehensive rehabilitative therapy, including hypersomnia medication (modafinil), physical therapy, and occupational therapy. OUTCOMES: His hypersomnia improved significantly with rehabilitation, with no daytime hypersomnia beginning 3 weeks after the surgery. On 2-week DTT, neither the neural tract of the left lower dorsal or ventral ARAS were reconstructed, but these neural tracts were wellreconstructed on 5-week DTT. LESSONS: In conclusion, restoration of nonreconstructed neural tracts of the lower ARAS with the resolution of the hematoma and perihematomal edema was demonstrated in a stroke patient, using DTT.