Herpes zoster virus causes the illness known as shingles. It is the same virus that causes the chicken pox. After infection with the chicken pox virus, the virus lays dormant in a sensory nerve. Years later during a time of stress or immunocompromise, this virus can reactivate, causing shingles.
Shingles manifests as a painful rash along a single dermatome. A dermatome is an area on the body supplied by a single spinal nerve. When the dermatome affected by shingles is supplied by the trigeminal nerve (the 5th cranial nerve), it can be dangerous to your eye. The trigeminal nerve supplies the area surrounding the eye. Any person affected by shingles that manifests itself on the face must be seen by an ophthalmologist, in addition to their primary care doctor.
Shingles can cause inflammation of almost any part of the eye, including the cornea. This is known as herpes zoster ophthalmicus or HZO. Our SightMD eye care professionals treat the condition with oral antiviral medication, and lubricating eye drops. Secondary bacterial infections can occur, so follow-up with an ophthalmologist is crucial. Any individual affected by HZO must have regular follow-up with his or her eye doctor because it’s possible to have recurrent inflammation and flares in the eye related to the virus. Furthermore, the virus itself can lead to permanent loss of sensation in the cornea. This is very dangerous because individuals are unable to feel pain on the cornea, which is protective against infection and desiccation.
It’s possible to develop permanent scarring on the cornea after the infection has healed. If the scarring is greatly interfering with vision, a corneal transplant can be considered.