Hamartoma of the optic nerve in a young child—case report and review of the literature

Hamartomas are well described but yet incompletely understood sporadic benign lesions that can arise in various locations. Hypothalamic hamartomas of infancy are often associated with severe developmental disturbances. We present a case of an infant boy with a hamartoma that arises from the optic nerve and lead to progressive unspecific seizure activity, behavioral problems and precautious puberty. A 1-year-old male patient was presented with horizontal nystagmus and developmental retardation. Magnetic resonance imaging (MRI) with contrast revealed an isointense mass ventral of the chiasm consistent with a hamartoma. Soon after the MRI, the mother of the patient reported gelastic-like seizures. The patient was evaluated by an interdisciplinary team, and surgery was recommended. Intraoperatively, a firm attachment to the optic nerve was recognized and a thin remnant layer of tissue was left behind. After an uncomplicated near total resection, the patient improved significantly. After 6 months, the frequency of seizures reoccurred, which were again unresponsive to antiepileptic medication. In a second operation, a complete resection of the remnants was performed, and the patient showed lasting clinical improvement. We conclude that hamartomas mimicking hypothalamic symptoms can also arise from the optic pathway and that a reoperation, if feasible, of even small remnants is essential in order to achieve lasting symptom relieve.