Extra ocular cysticercosis – Does the site matter?

Abstract

Cysticercosis is the most common parasitic disease of central nervous system. Seizure is the most common presenting feature. The presentation of ocular cysticercosis varies based on cyst location, from asymptomatic to diplopia to vision loss. Here we discuss 4 cases of extraocular cysticercosis, with a stereotypic presentation and unique location (Table 1). Orbital cysticercosis can present with a varied signs and symptoms like acquired strabismus, diplopia, recurrent redness of eye, and proptosis. It must be differentiated from other benign and malignant conditions presenting as ocular mass. One or more extraocular muscles may be simultaneously involved. A case report documented cysticercal cyst within the inferior rectus muscle. Another study has reported an unusual case of ocular cysticercosis involving the levator palpebrae superioris and superior rectus muscle of the right eye like in our case series. From a single centre, 4 cases of similar clinical and radiological features made us to hypothesize that the tropism of the cysts for superior rectus and levator palpebral superioris muscle is complex. The blood flow pattern or size of larva suiting the blood vessel or other immune related mechanism may play a role for this site prediction. Prompt diagnosis and treatment in these cases led to early and near complete improvement. Orbital cysticercosis is a preventable cause of blindness. From our case series we find that cysts have high tropism to involve levator palpebrae superioris and superior rectus for reasons still not known.