側脳室のentrapmentを来し，脳室拡大なく著明な浮腫を生じた脳膿瘍・脳室炎の1例

Brain Abscess and Ventriculitis Associated with Entrapment of the Lateral Ventricle Appearing More Like Remarkable Brain Edema than Ventricular Dilatation : a case report

I．はじめに

　脳膿瘍の治療過程において脳室炎を合併し，側脳室側角のentrapmentを来すことはよく知られている^1,2,3）．その際，孤立した側脳室内に脈絡叢があれば脳室拡大を来すことが多い．今回，脳膿瘍の治療過程で脳室炎に伴う側脳室三角部の癒着により側脳室側角のentrapmentを来したが，脳室拡大なく，著明な脳浮腫を呈した1例を経験したので報告する．

We present a case with brain abscess associated with entrapment of the lateral ventricle appearing morelike remarkable brain edema in the temporo-occipital lobe than ventricular dilatation. A 72-year-old mansuffering from headache and vomiting visited our clinic. CT and MRI showed brain abscess in the rightparieto-occipital lobe, associated with ventriculitis. Lumbar puncture also revealed purulent meningitis.Both symptoms and CSF findings improved after administration of antibiotics. The improved conditioncontined for two months after admission, but disturbed consciousness and left hemiparesis than appeared.MRI and CT showed entrapment of the lateral ventricle and brain edema of the right temporo-occipital re-gion without ventricular dilatation. Because brain edema was thought to be caused by transudate of theCSF through the ventricular wall, lobectomy of the right temporal lobe and opening of the temporal hornwere carried out. Although left hemiparesis and disturbed consciousness and brain edema disappearred af-ter the operation, subdural effusion appeared. Using a subdural-peritoneal shunt, the subdural effusion wasprevented and disappeared.

In this case, we thought Hounsfield Unit (HU) of the brain edema caused by transudate of CSF throughthe ventricular wall (12.6) was markedly lower than that of so-called vasogenic edema (25.1) due to activeinflammation. Measurement of the HU seemed to be a useful means to differentiate the types of brain ede-ma in this situation from that of vasogenic edema caused by brain abscess, and thus a means for selectionof the appropriate treatment.