In such cases an additional hyperopic correction is often prescribed in the form of bifocal lenses, to reduce the degree of accommodation, and hence convergence, being exerted. Many children will gradually learn to control their esotropias, sometimes with the help of orthoptic exercises. However, others will eventually require extra-ocular muscle surgery to resolve their problems. Congenital esotropia
Congenital esotropia, or infantile esotropia, is a specific sub-type of primary concomitant esotropia. It is a constant esotropia of large and consistent size with onset between birth and six months of age. It is not associated with hyperopia, so the exertion of accommodative effort will not significantly affect the angle of deviation. It is, however, associated with other ocular dysfunctions including oblique muscle over-actions, Dissociated Vertical Deviation (DVD), Manifest Latent Nystagmus, and defective abduction, which develops as a consequence of the tendency of those with infantile esotropia to cross fixate. Cross fixation involves the use of the right eye to look to the left and the left eye to look to the right; a visual pattern that will be natural for the person with the large angle esotropia whose eye is already deviated towards the opposing side. The origin of the condition is unknown, and its early onset means that the affected individuals potential for developing binocular vision is limited. The appropriate treatment approach remains a matter of some debate.
Autosomal recessive bestrophinopathy is a rare genetic disorder characterized by central vision loss, retinopathy, absence of an electrooculogram light rise, and decreased electroretinogram. Other findings include dispersed punctate flecks, macular neurosensory retina fluid build-up, hyperopia, macular thinning, and (less commonly) angle-closure glaucoma.It is caused by hereditary autosomal recessive mutations in the BEST1 gene, located in chromosome 11, and it has been described in less than 20 individuals from 10 families worldwide. == References ==