[Bilateral leukemic optic nerve infiltration as the first manifestation of extramedullary relapse in T-cell acute lymphoblastic leukemia].

T-cell acute lymphoblastic leukemia is a hematologic malignancy with propensity to involve extramedullary organs including the eyes. Optic nerve infiltration is relatively rare. This is the case study of a 25-year-old- man who was in full remission following treatment for T-cell acute lymphoblastic leukemia and presented with bilateral leukemic optic nerve infiltration as the first manifestation of extramedullary relapse. The patient was treated with urgent radiotherapy and systemic dexamethasone. Over the following period, gradual resolution of optic disc swelling was noted in both eyes with marked improvement in vision in the right eye. Unfortunately, a few weeks later, a full blown hematological relapse was diagnosed. Salvage chemotherapy was instituted but was complicated by tumor lysis syndrome and septicemia that proved to be fatal. Ophthalmic assessment is essential in patients with hematological malignancies in order to diagnose ocular involvement as a result of malignant infiltration, hematological disturbances or as a complication of systemic therapy.