Herpes Zoster Ophthalmicus

 Herpes Zoster Ophthalmicus

Definition

Facial rash caused by the varicella-zoster virus.

Epidemiology: 

The disorder usually affects immunocompromised personsbetween the ages of 40 and 60 who have underlying disorders.

Etiology: 

The disorder is caused by the varicella-zoster virus, which initiallymanifests itself as chickenpox. If activation or reinfection occurs, the latent neurotropic viruses present in the body can lead to the clinical syndrome of herpes zoster ophthalmicus (Fig. 2.14).


Symptoms: 

The incubation period is 7 – 18 days, after whichsevere painoccurs in the area supplied by the first branch of the trigeminal nerve (the ophthalmic nerve with its frontal, lacrimal, and nasociliary branches). Prodro-mal symptoms of erythema, swelling, photosensitivity, and lacrimation mayoccur before the characteristic clear watery vesicles appear. The vesicles burst and brownish scabs form, which are later shed. Blepharitis is also present in 50 – 70% of all cases. As herpes zoster usually affects immunocompromised persons, the patient should be examined for a possible underlying disorder.

The skin sensitivity at the tip of the nose should be evaluated on both sides in the initial stage of the disorder. Decreased sensitivity to touch suggests involvement of the nasociliary branch of the ophthalmic nerve, which can lead to severe intraocular inflammation.

Treatment: 

This includes topical virostatic agents and systemic acyclovir.

Complications: 

Involvement of the nasociliary branch of the ophthalmicnerve can lead to severe intraocular inflammation.

Prognosis: 

The skin lesions heal within three to four weeks; scars mayremain. Often neuralgiform pain and hypesthesia may persist.

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