Abstract
Abstract: :
Purpose:To report the unusual case of a 27 year old male presenting with see-saw nystagmus. Methods:High resolution magnetic resonance imaging of the optic nerve and tracts. Clinical assessment of eye movement. Results:on clinical exam the patient had no significant past medical or ocular history. His best corrected vision was 20/50 OD and 20/70 OS with full color vision, no pupillary abnormalities, full Goldmann visual field testing. He preferred a chin down position and no significant refractive error. His slit lamp examination was unremarkable. Dilated fundus exam and neurologic examination were normal. He had see-saw nystagmus in primary gaze with end gaze horizontal jerk component in extreme left and right gaze. MRI revealed the presumed failure of fusion of the optic chiasm or decussating fibers along the optic nerve and tract. There were no midline abnormalities or evidence of organic brain disease. Conclusions:In prior reports of seesaw nystagmus found in a specific breed of dog was associated with achiasm of the optic tract. Only three other patients(all female) in the literature have been reported to have similar eye movement findings and no evidence of decussating fibers at the chaism on MRI. This is the first male patient to be found to have congenital achiasm.
Keywords: neuro-ophthalmology: diagnosis • nystagmus • imaging methods (CT, FA, ICG, MRI, OCT, RTA, S