Change of Ascending Reticular Activating System Following Shunt Operation for Hydrocephalus in a Subarachnoid Hemorrhage Patient.

Abstract

To demonstrate the change of the ascending reticular activating system (ARAS) concurrent with the recovery of impaired consciousness following a shunt operation in a stroke patient. A 65-year-old female patient underwent coiling of a ruptured right posterior communicating artery and, subsequently, underwent right external ventricular drain (EVD) placement, left EVD placement, and lumbar drain placement for management of intraventricular hemorrhage. After 6 months from onset, she began rehabilitation, and brain magnetic resonance imaging showed dilatation of the ventricular system. The patient exhibited impaired alertness, with a Glasgow Coma Scale (GCS) score of 7. At ∼ 20 days after starting rehabilitation, the patient underwent a ventriculoperitoneal shunt operation for hydrocephalus. At 10 days postsurgery, her GCS improved to 15. Regarding the change of neural connectivity of the thalamic intralaminar nuclei, compared with preoperative diffusion tensor tractography (DTT), postoperative DTT showed that neural connectivity to the prefrontal cortex was increased in both hemispheres. In terms of configuration of DTT, the lower portion of the ARAS between the reticular formation and the intralaminar thalamic nuclei did not show a significant change. A patient with subarachnoid and intraventricular hemorrhage showed recovery of an injured ARAS and consciousness after a shunt operation for hydrocephalus.