A perimesencephalic distribution of nonaneurysmal subarachnoid blood on CT imaging has been described as a distinct clinical entity with a benign course and an excellent prognosis; research ...

Perimesencephalic NASAH is characterized by a distinctive pattern of blood seen on an initial CT scan performed within hours of symptom onset. The subarachnoid blood is confined to the midbrain ...

Methods Records of patients with a CTA-negative ntSAH at a single institution from 2014 to 2018 were retrospectively analyzed. ntSAH patterns were categorized as cortical, perimesencephalic, or ...