title: [A case of organized chronic subdural hematoma presented with transient neurologic deficits].
abstract: A 59-year-old diabetic male presented with transient motor aphasia and monoparesis of the right upper limb. Brain CT scan showed a low density area in the left subdural space with a mild midline shift. Magnetic resonance (MR) T2-weighted and fluid-attenuated inversion recovery (FLAIR) imagings revealed homogenous hyperintensity with a hypointense web-like structure in the subdural hematoma. Cervical MR angiography showed no abnormal lesion at the bifurcation of the bilateral common carotid arteries. Conventional cerebral angiography showed an avascular, crescent, space-occupying mass over the left hemisphere without an etiologic lesion of cerebral ischemia. CT perfusion imagings indicated reduced cerebral blood flow (CBF) and prolonged mean transit time (MTT) in the left middle cerebral artery territory underneath the subdural hematoma. No epileptic discharge was found in electroencephalogram. Operative findings indicated that the hematoma was encapsulated with thickened outer and inner membranes including paste-like materials, and the brain surface was intact. Postoperative CT perfusion imagings revealed normal CBF and MTT. The pathophysiological mechanism which the chronic subdural hematoma produces the transient neurological deficit is still uncertain. The mechanical pressure of the hematoma on the neighboring cerebral vessels may cause impairment of blood flow leading to cerebral ischemia and paralysis of function. Our case indicated the transient neurological deficits attributed to a decreased CBF around the subdural hematoma and a change in pressure exerted by the hematoma during changes of head position and increased blood viscosity.
authors.affiliation: Department of Neurosurgery, Mominoki Hospital, 6-1 Tsukano-hara, Kochi 780-0952, Japan.
authors.forename: Seikou
authors.initials: S
authors.lastname: Kuwahara
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Miyake
authors.forename: Yoko
authors.initials: Y
authors.lastname: Koan
authors.forename: Masaaki
authors.initials: M
authors.lastname: Fukuoka
authors.forename: Yuko
authors.initials: Y
authors.lastname: Ono
authors.forename: Akihito
authors.initials: A
authors.lastname: Moriki
authors.forename: Koreaki
authors.initials: K
authors.lastname: Mori
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Mokudai
authors.forename: Yasufumi
authors.initials: Y
authors.lastname: Uchida
mesh_terms: D002560:Cerebrovascular Circulation; D020200:Hematoma, Subdural, Chronic / Q000150:complications*; D006801:Humans; D002546:Ischemic Attack, Transient / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed