Ocular larva migrans
|Ocular larva migrans|
Ocular larva migrans is the ocular form of the larva migrans syndrome that occurs when toxocara canis larvae invade the eye. They may be associated with visceral larva migrans. Unilateral visual disturbances, strabismus, and eye pain are the most common presenting symptoms.
The disease presents with an eosinophilic granulomatous mass, most commonly in the posterior pole of the retina. The granulmatous mass develops around the entrapped larva, in an attempt to contain the spread of the larva.
The retinal lesion can mimic retinoblastoma in appearance, and mistaken diagnosis of the latter condition can lead to unnecessary enucleation.
The eye involvement can cause the following inflammatory disorders:
In contrast to visceral larva migrans, ocular toxocariasis usually develops in older children or young adults with no history of pica. These patients seldom have eosinophilia or visceral manifestations.