Optic neuropathy secondary to radiotherapy for nasal melanoma.

Optic neuropathy is a rare but important complication of radiotherapy used in the treatment of cancers of the head and neck, usually resulting in rapidly progressive blindness in one or both eyes. The case is presented of a 77-year-old woman with bilateral optic neuropathy resulting in blindness, secondary to radiotherapy for a melanoma of the nasal cavity. The onset of optic neuropathy occurred 9 months post-radiotherapy, at a cumulative dose of 6000 rad. The left eye was first involved, with the right eye becoming involved within 2 weeks. Despite treatment with oral anticoagulation and high dose intravenous methylprednisolone, there was progressive deterioration resulting in bilateral optic atrophy, with final visual acuities of perception of light in the right eye and no perception of light in the left eye. This case demonstrates that oral anticoagulation was ineffective in the treatment of progressive radiation-induced optic neuropathy.