Transient monocular vertical hemifield loss as a rare acute oxaliplatin-induced ophthalmological side effect: a case report and review of the literature.

Oxaliplatin commonly induces acute, transient peripheral neurotoxicity, most often presenting as cold-induced paresthesia. Ocular adverse events are rare and poorly understood. This case describes a rare, reproducible transient monocular visual field loss associated with oxaliplatin exposure. We report a patient treated with FOLFOX (5-FU + oxaliplatin) for metastatic rectal cancer who developed recurrent transient visual symptoms temporally associated with oxaliplatin infusion. Biological, neurological, and ophthalmological evaluations were performed. The patient experienced recurrent, transient left monocular vertical hemifield loss during oxaliplatin administration. Extensive neurological and ophthalmological investigations were unremarkable. Symptoms were fully reversible and reproducible across treatment cycles, occurring exclusively after oxaliplatin exposure. This case adds to the limited literature on oxaliplatin-associated ocular neurotoxicity and emphasizes that transient visual symptoms may represent a reversible form of acute neurotoxicity. Recognizing this entity is important to avoid premature discontinuation of an effective chemotherapy regimen.