Sensorial strabismus due to congenital toxoplasmosis. Is it an eso- or exotropia?

Objective: To examine sensorial strabismus due to congenital toxoplasmosis to elucidate differences and similarities between cases with esotropia (ET) and with exotropia (XT).

Methods: Restrospective analysis of 49 patients treated between 2002 and 2007. Visual acuity, cycloplegic refraction, strabismus patterns, presence of nystagmus, site of scar, surgery performed and strabismus surgical outcome obtained were evaluated.

Results: Mean age: 5 years old. 25 patients had bilateral involvement: 10 had ET, 10 XT and 4 were aligned. 15/24 unilateral cases presented with XT, 7 ET and other 2 orthotropia. 6/8 patients with the right eye affected, manifest ET and 14/16 patients with their OS affected had XT. (P=0.01)

Conclusion: In bilateral cases of ocular toxoplasmosis ET and XT are found in similar proportions; in unilateral cases, XT is more frequent and the left eye is affected in most cases by both the toxoplasmosis and the strabismus. Esotropia appears more frequently in cases where the right eye is so affected, whereas XT predominates in cases where the left eye is affected.