Herpes Zoster Opthalmicus (Shingles)

Herpes Zoster Ophthalmicus (HZO) is an eye condition caused by the Varicella Zoster vius which also causes chickenpox. The virus generally lies dormant in the body after a childhood episode of chickenpox. The virus infects the nerve supplying sensation to the eye surface, eyelids, forehead and nose. It is thought to reactivate if the immunity to the VZV is weakening, or the immune system is not functioning normally (ill-health, HIV or immunosuppression therapy or chemotherapy). When the condition affects the skin it is called shingles, and when the eye is involved it is called HZO.

Any part of the eye can be involved, along with the skin on one side of the forehead and scalp. The most common long-term effect is damage to the corneal nerves causing loss of sensation.

Patients with shingles generally report a week or so of flu-like symptoms or just feeling unwell. The affected skin is reported to be tingly and very sensitive to touch, then a pustular rash appears. In HZO the area involved is supplied by the upper division of the ophthalmic nerve which supplies the forehead, the eyelids, and sometimes the tip of the nose. The ear on the affected side can be involved too. Most patients report significant neuralgia (nerve pain).

Symptoms can include:

• Severe pain on one side of the face, in the scalp, or around the eyes.
• Redness, rash, or sores on your eyelids and around the eyes, particularly the forehead and occasionally on the tip of the nose.
• Eye redness.
• A swollen or cloudy cornea.
• Rarely double vision (if the nerves responsible for eye moment are involved).
• Rarely profound vision loss (if the optic nerve or retina is involved).

Investigations may include:

• Vision assessment.
• Slit lamp examination with corneal stain (“pseudodendrites” may be seen). Also the anterior chamber is assessed for the presence of calls (white blood cells) or flare (protein) which can indicate the presences of uveitis.
• Dilated examination to check for any retinal involvement

Patients with HZO should be commenced on oral anti-viral medications within 72 hours of the onset of the rash. This generally reduces the duration of the skin rash and the severity of the post herpetic neuralgia.

Ocular treatments that may be required include:

• Steroid drops – may be required to treat intraocular inflammation, and can reduce corneal scarring. In some patients, a low dose steroid drop may be required ongoing.
• Mydriatic (dilating) drops – may be required to reduce the ciliary spasm that comes if uveitis is present.
• Ocular lubricants – may be required long term if dry eye symptoms are ongoing.
• Pain relief medication may be required in some cases for the neuralgia.