Alterations of Ocular Motility in down Syndrome

Abstract

Introduction and Objective:

In Down syndrome ophthalmologic alterations have been reported in all ocular elements, including, commonly, alterations in ocular motility. The object of the present study was to determine the frequency, type and characteristics of ocular motility alterations in Down Syndrome and to determine its correlation with the various karyotype possibilities.

Patients and Method:

A prospective, cross-sectional and observational study was designed in patients with a karyotype confirmed diagnosis of Down Syndrome. A complete strabismic examination was made in patients that included retinoscopy with 1% tropicamide cycloplegia.

Results:

Alterations in ocular motility were found in 119 (59.5%) of the 200 studied patients. The most frequent ocular motility alterations were strabismus and nystagmus. Esotropia (ET) was the most frequent and in nearly half of the cases was associated with high myopia (−6.00 D on average). The second most common alteration was nystagmus. This was characteristically horizontal, of small amplitude, fast and pendular. It was generally associated with ET. Exotropia was the least frequent alteration. There was no correlation between the type of motility problem and the morphology of karyotype causing Down Syndrome.

Conclusion:

The characteristic deviation in Down syndrome is primary esotropia. Phenotypic and ocular motility alterations are similar in trisomy, translocation and mosaicism.

• Down Syndrome
• esotropia
• strabismus
• nystagmus