[Skip to Navigation]
Views 2,014
Citations 0
Teachable Moment
Less Is More
August 2016

A Common Cause of Cranial Nerve VI Palsy—Hidden in Plain Sight: A Teachable Moment

Author Affiliations
  • 1Department of Medicine, Duke University Medical Center, Durham, North Carolina
  • 2Department of Pediatrics, Duke University Medical Center, Durham, North Carolina
JAMA Intern Med. 2016;176(8):1066-1067. doi:10.1001/jamainternmed.2016.2661

An otherwise healthy man in his 30s presented to an optometrist with sudden onset horizontal diplopia and blurry vision. Symptoms increased in severity as his gaze turned to the left. Physical examination was notable for left sixth cranial nerve palsy. The remainder of the neurologic examination was normal. The optometrist ordered a magnetic resonance imaging (MRI) scan of the brain with and without contrast that revealed asymmetric left-sided enhancement of the dura in the region of Dorello’s canal (Figure). The differential diagnosis remained broad and a lumbar puncture was recommended by the neuroradiologist to evaluate for a dural-based process such as neurosarcoidosis.

Add or change institution