[Interhemispheric subdural hematoma]

The interhemispheric subdural hematoma (ISH) is a special subdural hematoma with regard to both location and symptomatology. The most widely described clinical signs and symptoms associated with an ISH are a lucid interval and the falx syndrome. The latter is featured by a contralateral hemiparesis that is accentuated in the lower extremity but spares the face. Minor head trauma or a preexisting coagulation disorder are also often found. Nonsurgical treatment should be chosen in patients with little neurologic dysfunction and a stable clinical course. Patients with progressive neurologic deterioration and focal neurologic deficits should be operated on without delay. This article provides a review of 99 published cases of ISH and adds 3 cases to the existing literature.