Abstract 102: Pseudo‐Internuclear Ophthalmoplegia in a Patient with an Acute Globus Pallidus Infarct: A Case Report

Abstract

Introduction Internuclear ophthalmoplegia (INO) is an ocular movement disorder typically due to a lesion in the medial longitudinal fasciculus (MLF). Rarely, similar ocular movement abnormalities can be observed in the absence of an MLF lesion. This case report aims to highlight a potential association between acute globus pallidus (GP) infarct and an ocular movement abnormality resembling INO. Methods N/A Results Case Presentation: A 72‐year‐old male with a medical history significant for chronic myeloid leukemia, prostate cancer, type 2 diabetes mellitus, hypertension, prior stroke, and heart failure presented with dizziness. Examination revealed right INO, skew deviation with right hypertropia, left lower extremity weakness, left upper extremity dysmetria, right facial weakness (prior deficit), and ataxic gait. MRI of brain confirmed an acute lacunar infarct in the right globus pallidus with no apparent brainstem or cerebellar lesion. The patient was started on dual antiplatelet therapy and discharged with home rehabilitation services to improve his balance. Discussion: The patient presented with pseudo‐INO in the setting of an acute globus pallidus infarct. This case introduces the idea that ocular motor abnormalities resembling INO could occur due to a GP lesion, which was not previously reported. The basal ganglia control saccadic eye movements by means of their connection to the superior colliculus (SC). GP was shown to have a role in this connection which may provide a plausible explanation for this observation. Another possible explanation can be based on the concept of diaschisis, where a lesion in a specific area of the brain (GP in this case) can lead to deficits or impairments in various functions associated with that region (the SC and its pathway for controlling saccadic eye movement). Conclusion This case emphasizes that slow adducting saccades and associated nystagmus is not always INO.