Looking Beyond the Midline: An Uncommon Etiology of Internuclear Ophthalmoplegia of Abduction Due to Cerebral Venous Thrombosis.
Dipti Baskar, Aravinda G Maheswarappa
✦ AI-curated · Sources linked
Case in brief
A 27-year-old man presented with headache, vomiting, seizures, and altered sensorium. Examination revealed bilateral disc edema and abduction restriction of the right eye, consistent with internuclear ophthalmoplegia (INO) of abduction. Brain MRI showed no lesions, but MR venography confirmed cerebral venous thrombosis. Treatment with anticoagulation and acetazolamide led to complete resolution of ocular motility deficits.
What made this case unusual
The case illustrates an exceptionally rare variant of INO characterized by abduction limitation without structural brainstem lesions, likely due to pressure-mediated disruption of gaze pathways.
Diagnostic / clinical pearl
Clinicians should consider INO of abduction in patients with intracranial hypertension and normal brainstem imaging, as it may indicate underlying cerebral venous thrombosis.
Why it matters
Recognizing this variant can facilitate timely and reversible treatment, improving patient outcomes in cases of raised intracranial pressure.