We report the case of a 16-year-old girl with B-ALL in remission for 8 months who presented with unilateral visual loss and papilledema. We also conducted a systematic review of the literature, identifying 23 cases of leukemic optic nerve relapse. Data were extracted on demographics, leukemia subtype, clinical presentation, diagnostic testing, treatment, and outcomes.

Our patient presented with visual acuity 20/200 OS, a left relative afferent pupillary defect, and bilateral Frisen grade 5 disc edema. Initial MRI was normal, while CSF revealed 950 lymphoblasts/µL. Bone marrow biopsy confirmed relapse. Notably, her complete blood counts (CBC) remained normal, indicating that a screening CBC would not have detected the relapse.

Across the pooled cohort of 24 patients, median age was 19 years (range 2-73). Presentations were unilateral in 52% and bilateral in 48%, with optic neuropathy as the initial sign of relapse in all cases. Initial MRI was normal or equivocal in 74%, and CSF cytology was negative in 56%. Intrathecal therapy was administered in 96%, and cranial/orbital radiation in 57%. Visual outcomes were variable: 54% experienced recovery or preservation, while 21% progressed to no light perception.

Leukemic optic nerve infiltration is a rare but sentinel presentation of ALL relapse, with only scattered reports previously available. By unifying 24 cases, we highlight diagnostic pitfalls and variable outcomes.