We report a case of a 43-year-old man treated by
craniotomy for chronical
subdural hematoma (CSH) due to spontaneous intracranial
hypovolemia. The patient complained of sudden onset severe
headache. Initial CT scan showed normal brain structure, and his
headache improved with
bed rest in a few days. However, MR images obtained for
vertigo one month later demonstrated bilateral
subdural hygroma extending to the supracerebellar space and diffuse dural enhancement after
gadolinium infusion. We diagnosed bilateral
subdural hygroma due to spontaneous intracranial
hypovolemia, and observed him conservatively. Four months after onset, he complained of severe
headache again and MR images revealed enlargement of bilateral CSH with mass effect, which had heterogenous intensity on the right convexity. We evacuated
hematoma on the right by
craniotomy and aspirated the left side
hematoma using a burr hole. His
headache improved 2 weeks after the operation with strict
bed rest. The follow-up MR images showed disappearance of abnormal meningeal enhancement and improvement of brain sagging.