Interhemispheric arachnoid cyst in the elderly: case report and review of the literature.

BACKGROUND: Preoperative differential diagnosis of interhemispheric cysts is sometimes difficult. CASE DESCRIPTION: We recently experienced a case of symptomatic interhemispheric arachnoid cyst in a 62-year-old woman. We reviewed interhemispheric arachnoid cysts in the elderly and the management of symptomatic interhemispheric arachnoid cysts in elderly patients. Symptomatic interhemispheric arachnoid cysts in the elderly are predominantly located on the right side, have a long history of progressive symptomology, occur predominantly in females, and have no communication with the subarachnoid space. Interhemispheric arachnoid cysts are usually not associated with agenesis of the corpus callosum in elderly patients, whereas interhemispheric nonarachnoid cysts are usually associated with agenesis of the corpus callosum, which will be clearly demonstrated on magnetic resonance imaging.
CONCLUSIONS: It is highly possible that an interhemispheric cyst without agenesis of the corpus callosum in an adult is an arachnoid cyst.