Leukaemic Optic Neuropathy in a Patient with Treated Acute Lymphoblastic Leukaemia: Optical Coherence Tomography as an Aid to Diagnosis.

Leukaemic optic neuropathy is an uncommon cause of visual loss which represents a neuro-oncological emergency with the potential of irreversible blindness if untreated. It can be difficult to diagnose, often presenting with normal neuroradiological and cerebrospinal fluid findings. We present the case of a 26-year-old woman with T-cell acute lymphoblastic leukaemia with optic neuropathy secondary to leukaemic infiltration, who demonstrated features on optical coherence tomography that aided the diagnosis of this condition. This included the presence of numerous, small, hyperreflective opacities erupting from the optic nerve head, which improved following treatment with radiotherapy and chemotherapy, and later recurred when the condition relapsed. This finding may help clinicians differentiate between other causes of optic neuropathy as well as assessing response to treatment and monitoring for recurrence.