Typical ocular finding is a large granulomatous scar with fibrous bands radiating from the lesion and retinal pigment epithelium (RPE) hyperplasia. Associated vitritis and even iritis are possible.

The Toxocara canis nematode is carried by dogs. It is most commonly found in the southeastern US, and is a major problem worldwide. It is ingested by humans usually as the result of eating soil tainted with dog feces or occasionally undercooked meat. Eggs can remain viable in humans for years, then activate into mobile larvae. The entire life cycle of Toxocara canis can be carried out in dogs; however, only the larval stage occurs in humans. Larvae enter the eye via the blood stream, resulting in formation of a granuloma. There are two forms--Visceral Larvae Migrans (VLM) and Ocular Larvae Migrans (OLM) which do not typically exist together. VLM occurs between ages one and four and is systemic; OLM, which occurs later in childhood into adolescence, is ocular. The vague nature of VLM symptoms (including fever, weight loss, vomiting) often prevents accurate diagnosis.

The three images below are examples of Toxocara canis from other patients.
Our Case 2 patient had originally and mistakenly been diagnosed several years ago as having a coloboma. The image to the right is a true coloboma.