Limited efficacy of endoscopic third ventriculostomy for hydrocephalus following aneurysmal subarachnoid hemorrhage.

Endoscopic third ventriculostomy (ETV) has not been recognized as a surgical option for hydrocephalus following aneurysmal subarachnoid hemorrhage (SAH), since hydrocephalus following aneurysmal SAH is considered to result from the communicating component. However, obstructions in the ventricular system may exist, so ETV could help resolve the condition. The present study evaluated the efficacy of ETV for hydrocephalus appearing within one month after aneurysmal SAH. This prospective study evaluated a total of 118 patients admitted to our hospital with aneurysmal SAH. Nine of 66 surgically treated patients suffered hydrocephalus within one month after aneurysmal SAH and 8 underwent ETV. Seven of these 8 patients showed no further ventricular enlargement or deterioration in consciousness, and required no external cerebrospinal fluid (CSF) drainage at least temporarily, and could commence early physical rehabilitation. Four patients also experienced cognitive improvements after ETV, but none made a full cognitive recovery. Ventriculoperitoneal (VP) shunt was implanted for one patient who did not respond to ETV, and the necessity of VP shunt was evaluated including the CSF removal test for the other patients, due to residual cognitive impairment even after initiating the rehabilitation. Five of the 8 patients eventually had VP shunts implanted, and 3 patients, including two patients who improved cognitively after ETV, had further cognitive improvements. ETV for hydrocephalus following aneurysmal SAH is likely to help manage intracranial pressure. ETV may improve cognitive impairment in some patients, but whether the maximum resolution is obtained only with ETV remains uncertain. VP shunt implantation should be the main treatment for hydrocephalus after aneurysmal SAH, but ETV can be employed as a temporary intervention in certain conditions, such as during the waiting period for the clearance of aneurysmal SAH.