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

Strabismus

Strabismus is a condition in which the eyes are not properly aligned with each other. It typically involves a lack of coordination between the extraocular muscles, which prevents bringing the gaze of each eye to the same point in space and preventing proper binocular vision, which may adversely...

, and eye pain are the most common presenting symptoms.

Exam findings

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.

Differential diagnosis

The retinal lesion can mimic retinoblastoma

Retinoblastoma

Retinoblastoma is a rapidly developing cancer that develops in the cells of retina, the light-detecting tissue of the eye. In the developed world, Rb has one of the best cure rates of all childhood cancers , with more than nine out of every ten sufferers surviving into...

 in appearance, and mistaken diagnosis of the latter condition can lead to unnecessary enucleation.

Complications

The eye involvement can cause the following inflammatory disorders:

• endophthalmitis
  Endophthalmitis
  Endophthalmitis is an inflammation of the internal coats of the eye. It is a dreaded complication of all intraocular surgeries, particularly cataract surgery, with possible loss of vision and the eye itself. Infectious etiology is the most common and various bacteria and fungi have been isolated as...
  
  
• uveitis
  Uveitis
  Uveitis specifically refers to inflammation of the middle layer of the eye, termed the "uvea" but in common usage may refer to any inflammatory process involving the interior of the eye....
  
  
• chorioretinitis
  Chorioretinitis
  Chorioretinitis is an inflammation of the choroid and retina of the eye. It is also known as choroid retinitis.-Causes:...
  
  

Epidemiology

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.