External ophthalmoplegia with orbital myositis in an adult patient after chickenpox infection.

Herpes zoster and chickenpox are caused by a single virus, varicella-zoster virus. Herpes zoster ophthalmicus-associated ophthalmoplegia is well documented. Very rarely, herpes zoster and chickenpox cause external ophthalmoplegia. A 48-year-old man was diagnosed with chickenpox and treated with intravenous acyclovir. He suddenly reported diplopia and restricted left eye movement. MRI of the orbit revealed thickening and abnormal contrast enhancement of the preseptal space and lateral rectus muscle of the left eye. In this case, external ophthalmoplegia occurred following chickenpox with radiological evidence of orbital myositis. To the best of our knowledge, this is the first case report of external ophthalmoplegia of radiologically confirmed orbital myositis after chickenpox infection.