Visual hallucinations: A novel complication after hemispherectomy

Two patients at our center experienced florid visual hallucinations following hemispherectomy. The first patient had drug-resistant left hemispheric focal seizures at 20 months of age from a previous stroke. Following functional hemispherectomy at age 3, he experienced frightening hallucinations 1 month post-operatively lasting 3.5 months. Our second patient underwent subtotal hemispherectomy at age 6 for drug-resistant focal seizures from right hemispheric cortical dysplasia. Eighteen months later he developed scary visual hallucinations during which he would shout and throw things. Hallucinations recurred for 6 months. In our experience in these patients, even though symptoms were florid, they were transient and subsided 3-6 months later.