Bilateral Progressive Optic Neuropathy in a Patient with Familial Amyloid Polyneuropathy: Amyloid Deposits in the Optic Nerve Head?

Familial amyloid polyneuropathy is a rare autosomal dominant hereditary disease. Optic nerve involvement is frequently observed secondary to uncontrolled glaucoma but, rarely, an ischaemic optic neuropathy can occur. In this case report we describe a patient who presented with bilateral progressive visual loss and constriction of his visual fields. Fundus examination showed intense paleness of both optic discs with elevated, poorly defined margins that seemed to be infiltrated. Fundus autofluorescence and enhanced-depth imaging optical coherence tomography ruled out the presence of optic disc drusen. Orbital magnetic resonance imaging ruled out any sign of orbital compression, inflammation or infiltration of the optic nerve. The mechanism of small vessel amyloid infiltration and a possible vessel compression by amyloid in the optic nerve head is discussed.