Complex visual hallucinations after occipital cortical resection in a patient with epilepsy due to cortical dysplasia.

BACKGROUND Charles Bonnet syndrome is a rare disorder characterized by complex and recurrent visual hallucinations in elderly patients with visual pathway pathologic defects. To date, to our knowledge, it has not been described in patients undergoing surgical resection for occipital lobe epilepsy due to cortical dysplasia. OBJECTIVE To describe a patient who experienced complex visual hallucinations following resection of cortical dysplasia on the right occipital lobe and who was diagnosed as having Charles Bonnet syndrome. PATIENT A 35-year-old woman underwent surgical resection for medically intractable epilepsy caused by cortical dysplasia involving the right occipital lobe. RESULTS Two months after resection of the epileptogenic zone, complex visual hallucinations in the left visual field not associated with loss of consciousness or delusion developed in the patient. Hallucinations persisted for more than 12 months despite treatment with antiepileptic medications. During hallucination, no electrographic seizures were recorded through long-term video-electroencephalographic monitoring. CONCLUSIONS Charles Bonnet syndrome may occur in a patient with occipital lobe epilepsy following resection of the diseased brain with a developmental malformation. Charles Bonnet syndrome associated with surgical treatment of occipital lobe epilepsy may have been overlooked.