Acquired Downbeat Nystagmus This 62 yo AA female reported to clinic for retinal evaluation of diabetic PDR. A downbeat nystagmus was present (although the patient had a difficult time focusing on the target). After noticing the nystagmus the patient was further questioned and reported that she experienced frequent dizziness. She was informed several years ago about the nystagmus, but further workup was deferred at that time. An MRI of the brain/brainstem without contrast (no contrast due to dialysis) was ordered and showed a cerebellar tonsillar herniation consistent with a possible Chiari malformation. A follow up MRI of the cervical and thoracic spine was recommended, which revealed that the upper cervical spinal cord was anteriorly displaced by a large Chiari I malformation. The cerebellar tonsillar herniation measured ~2.3 cm below the foramen magnum. The patient was sent to a neurosurgeon, who elected to observe rather than perform surgery. Bennett & Bloom Eye Center @anterior_seg_rocks #Downbeat #Nystagmus #clinical #video #ophthalmology #physicalexam #neurology
