Bifocal optic and facial nerve t-cell lymphoma.

Purpose: Optic nerve and optic nerve sheath infiltration by a systemic lymphoma is uncommon, but is exceedingly rare when caused by a T-cell lymphoma. This then generally occurs in association with central nervous system (CNS) involvement. We report on a rare case of optic and facial nerve T-cell lymphoma infiltration, without CNS involvement.

Methods: A 63-year old female with systemic T-cell lymphoma in clinical remission presented with painful loss of vision in the left eye. She was initially treated for presumed recurrent optic neuritis. A thorough clinical work-up was performed, followed by an optic nerve biopsy with histopathology.

Results: There was no perception of light in the left eye, with a marked relative afferent pupillary defect. Fundoscopy showed significant optic disc oedema and a large peripapillary subretinal infiltration. Subsequently, she developed a 7th cranial nerve paresis. Cranial MRI showed thickening and contrast enhancement of the left optic nerve and right facial nerve. Optic nerve biopsy showed infiltration of CD3- and CD5- positive lymphocytes. A complete systemic workup revealed no evidence of disease elsewhere. The patient was thus considered to have bifocal cranial recurrence of T-cell lymphoma, for which radiotherapy was started.

Conclusions: Optic nerve infiltration from systemic lymphoma is rare and generally occurs with CNS involvement. A bifocal pattern of recurrence from systemic T-cell lymphoma involving the right facial nerve and left optic nerve was seen in this patient. A review of the literature highlights the highly atypical nature of this presentation.