Intrahemispheric subdural hematoma complicated with chronic neurologic diseases

Two patients had interhemispheric subdural hematoma (ISH) without clinical signs or symptoms characteristic of ISH. The first patient, a 74-year-old woman with 7 years' history of Parkinson's disease, complained of unresponsiveness and akinesia. The treatment for suspected worsening of the disease failed to improve her conditions. Computed tomography (CT) showed hyperdensity along the falx from the frontal falx over the tentorium. Subsequent CT on the 23rd hospital day showed disappearance of hyperdensity, confirming ISH. The second patient, a 76-year-old woman with multiple cerebral infarction, was referred for loss of consciousness and vomiting. Neurological examination failed to reveal additional or augmented neurological deficits. Computed tomography showed a right parasagittal thin crescent hyperdensity with a flat medial border and a convex lateral border, extending from the anterior falx to the mid-falx. The hyperdensity disappeared on the 47th hospital day. These findings suggest the usefulness of CT as the only procedure when ISH features are not seen. (Namekawa, K.)