Clinical Features Associated with the Direction of Deviation in Sensory Strabismus

PURPOSE: To assess the clinical features associated with the direction of deviation in sensory strabismus and postoperative stability of strabismus angles. METHODS: The authors retrospectively reviewed the medical records of 98 patients diagnosed with sensory strabismus who were treated surgically. Among the factors analyzed were sex, age, direction of strabismus, preoperative visual acuity, age at onset of visual loss, cause of primary sensory deficit, refractive error, age at operation, deviation angle at 1 and 6 months postoperatively and after at least 5 years. RESULTS: At baseline, 20 patients (20.4%) had esotropia and 78 (79.6%) had exotropia. Common causes of primary sensory deficit were corneal opacity (25.5%), vitreoretinal disorder (23.5%), and congenital cataracts (16.3%). The proportion of esotropia increased significantly as the refractive error of the sound eye became more hyperopic. The older the patients were when they lost their vision, the higher the proportion of exotropia. Patients with longer duration of vision loss were more likely to have a larger deviation angle with exotropia, but the association was not significant with esotropia. CONCLUSIONS: Patients with sensory strabismus tend to develop exotropia. Refractive error of the sound eye and age at onset of vision loss were associated with the direction of strabismus. Despite poor sensory fusion even after surgery, more than 50% of patients maintained a stable eye position.

The Clinical Consideration of Sensory Strabismus

PURPOSE: To evaluate the factors influencing the direction of sensory strabismus and the consequent surgical outcomes. METHODS: We retrospectively reviewed the medical records of 150 sensory strabismus patients who had undergone surgery. Consisting of 38 esotropes and 112 exotropes. Parameters considered were the cause of vision loss, the age at vision loss, the refractive error of the sound eye, the interorbital distance in the posteroanterior view of the orbit, the deviation angle at postoperative 6 months and 1 year. Patients were excluded if the cause of vision loss was strabismic amblyopia. RESULTS: The major causative factors of sensory strabismus were corneal opacity (26.7%) followed in frequency by cataract (22.7%), and optic nerve disorder (15.3%). The age at vision loss, the refractive error of the sound eye, and the inner and outer interorbital distance were statistically significant among the considered factors in determining the direction of sensory strabismus. At postoperative 6 months, 69.3% of the patients maintained the alignment within 10 PD of orthotropia and 70.4% at 1 year. CONCLUSIONS: We considered that the age at vision loss, the refractive error of the sound eye, and the inner and outer interorbital distance could play a role in determining the direction of sensory strabismus. In spite of the deficit of sensory fusion, the surgical outcomes of sensory strabismus remained favorable at 1 year after surgery.