Abstract
Objective 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.
Methods 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.
Results 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.
Conclusions A patient with subarachnoid and intraventricular hemorrhage showed recovery of an
injured ARAS and consciousness after a shunt operation for hydrocephalus.
Keywords
diffusion tensor imaging - ascending reticular activating system - consciousness -
stroke
