Herpes zoster ophthalmicus
This viral infection is associated with a previous childhood exposure to varicella zoster (chickenpox) which remains hidden within and becomes active later in life when immune functions of the body weaken.
The chief focus of infection is in the trigeminal (gasserian) ganglion from where the virus travels down one or more of the branches (supraorbital, supratrochlear, infratrochlear) of ophthalmic division of the trigeminal. (V1). It is nearly always unilateral.
☆ Hutchinson's sign: Involvement of the nasociliary branch of trigeminal nerve may form vesicles on the tip of nose. (it is an important sign which denotes the progression of HZO)
☆ The characteristic rash proceeds from papules to vesicles formation and its further transition to pustules and scabs (healing after formation of rows of scars).
*Papules-> Vesicles-> Pustules-> Scabs.*
Other signs and symptoms:
- fever and malaise (at the onset)
- severe neuralgic pain
☆ Punctate corneal epithelial erosions
☆ Pseudodendritic keratitis (usually seen in corneal periphery)
- Nummular keratitis (large discoid lesions)- stromal granular deposits within 10 days of rash.
- Anterior uveitis - within 2 weeks of onset of rash.
☆ Red and edematous lids (unilateral)
☆ suppuration of vesicles associated with bleeding (within 3 weeks of onset)
- Iridocyclitis (due to deep stromal inflitration)
- Episcleritis and scleritis (gray- scarred areas)
- Iris atrophy
- Secondary glaucoma
☆ Nerve palsies (III, VI, VII)
- Cataractous changes in lens and surgical complications.
- Optic neuritis
- Antivirals: Systemic administration of Acyclovir 800mg x5 times daily for 10 days as soon as possible.
- Analgesics to relieve the pain (stronger drugs such as opioids may be tried in severe cases)
- Corticosteroids in case of nerve palsies and neuritic pains. In case of scleral or corneal involvement and the further sequelae, dexamethasone 0.1% drops 4 hourly in addition to antiviral ointment (five times a day)
- NSAIDs (oxyphenbutazone) in case other steroids have not been effective.
- Artificial tears (to prevent dryness of the eye)
- Tarsorrhaphy (for neurotrophic ulcers)
- Jaskunwar Singh