Source: NIAID. Available online: http://www3.niaid.nih.gov/

Herpes zoster ophthalmicus is caused by the same virus that causes chickenpox (varicella-zoster virus). Herpes zoster is commonly called shingles. If shingles affects a certain nerve (trigeminal nerve) in the head, it causes itching, tingling, and a rash on the forehead, cheek, nose, and around one eye. It potentially threatens eyesight.