(DRG) Departments of Neurology, Ophthalmology, Neurosurgery, Otolaryngology - Head & Neck Surgery, Emergency Medicine, and Medicine, The Johns Hopkins School of Medicine, Baltimore, Maryland
Subject
Abnormal Saccades; Abnormal Range
Description
This is a 65-year-old man with multiple vascular risk factors who experienced the abrupt onset of diplopia 6 months prior to this video. MRI done within 24 hours of onset was unremarkable. Examination demonstrated subtle bilateral adduction lag with horizontal saccades. There was very mild abducting nystagmus to the right and left (not seen well in this video), also supportive of bilateral internuclear ophthalmoplegia (INO) in conjunction with the adduction lag. Despite the ‘normal' MRI, the etiology was felt to be ischemia (with false negative MRI) involving bilateral medial longitudinal fasciculi given his vascular risk factors and abrupt onset of improving symptoms. The diplopia resolved over months although a sensation of "visual lag" persisted when looking quickly to the right or to the left. This symptom was well explained by his adduction lag with horizontal saccades.