Slow Horizontal, Vertical, Oblique Saccades and Gaze-evoked Nystagmus in Anti-AGNA-1 Encephalitis

This is a patient who presented subacutely with imbalance and dizziness. On examination, she had evidence of gaze evoked nystagmus, right internuclear ophthalmoplegia, as well as slow saccades horizontally and vertically. She was diagnosed with a rare antibody-mediated disorder, anti-AGNA-1 (antiglial nuclear antibody-1) encephalitis. No neoplasm was found on PET/CT body, and while she has not progressed further since starting intravenous immunoglobulin, unfortunately she has also not improved significantly.; ; Given the fact that her saccades are equally slow horizontally and vertically, when oblique saccades were assessed, there was no curved or L-shaped trajectory, which can be seen in certain conditions where horizontal saccades are affected more than vertical or vice versa.