Down syndrome: a review of ocular manifestations

Abstract

Down syndrome is the most common genetically mediated intellectual disability. Although many physiologic and pathologic features of Down syndrome are discussed at length in the literature, the ocular manifestations of Down syndrome have seldom been discussed in a comprehensive fashion. Given that Down syndrome has ocular manifestations from the front to the back of the eye, it is important for physicians to become familiar with these manifestations, especially given the prevalence of Down syndrome. This review aims to discuss the varied ophthalmologic manifestations of Down syndrome - including strabismus, amblyopia, nystagmus, accommodation deficits, nasolacrimal duct obstruction, keratoconus, optic nerve pathology, neoplastic disease, and retinal pathology - to facilitate better care and visual outcomes in this important patient population.

Keywords: Down syndrome; cataract; hypoaccommodation; keratoconus; optic nerve.

Figure 1.

Clinical photograph of non-accommodative esotropia in a patient with Down syndrome.

Figure 2.

Example images from our patients. (a) An 11-year-old girl interpreted as abnormal cornea but not as keratoconus suspect because of thin and steep cornea but no evidence of ectasia. (b) A 13-year-old girl interpreted as keratoconus suspect because of inferior steepening and overall steep Ks. (c) A 20-year-old man interpreted as keratoconus because of severe steepening of the cornea both anteriorly and posteriorly, with corresponding corneal thinning. Reprinted from Imbornoni et al. 2020 with permission from Elsevier.

Figure 3.

Clinical photograph demonstrating Brushfield spots in a patient with Down syndrome.

Figure 4.

Clinical photograph of a cerulean cataract in a patient with Down syndrome.

Figure 5.

Small optic disks in Down syndrome. (a) Small optic disk with vascular tortuosity in a child with Down syndrome. This image exemplifies the formula used in the estimation of the disk-to-macula (DM) distance to disk diameter (DD) ratio (DM/DD): Dfx2 + D1/D1 + D2 (38, 39). Both vertical and horizontal DDs were considered, to compensate for oval disks. (b) Small, round optic disk with a double ring sign between the black arrows. (c) Hypoplastic disk of a child with Down syndrome. Papillary vascular malformation is evident. A large halo of peripapillary atrophy is seen at 360° (white arrows). The gray arrow indicates an area of pigmented epithelium hypertrophy at the temporal margin of the disk. (d) Small tilted optic disk in a child with Down syndrome and myopia. A scleral crescent is visible at the temporal margin (between the black arrows). The disk is oval and bean-shaped in this case, with a hyperpigmented halo. An extensive area of peripapillary atrophy, with visible choroidal vessels, is evident (white arrows). Reprinted from Postolache 2019 with permission from Frontiers.

Figure 6.

Optic nerve crescents in children with Down syndrome. (a) Oval and tilted optic disk with a temporal crescent (black arrows) in a child with Down syndrome and myopia. (b) Choroidal crescent located temporally (black arrows) in a small, tilted disk from a child with Down syndrome and high myopia. (c) Small temporal crescent (black arrows) in a child with Down syndrome and hyperopia. (d) Small, tilted disk with vascular tortuosity. A scleral crescent is located below the disk and extends nasally (black arrows). (e) Tilted disk with situs inversus of the vessels (striped arrows). A large choroidal crescent is evident below the disk and extending into the nasal area (between the black arrows). Peripapillary atrophy is noted at the temporal margin of the disk (white arrows). (f) Tilted disk in which the scleral crescent, although wider below the disk, takes an annular form. Situs inversus, in which the vessels emerge nasally, is also evident (striped arrows). (g) Choroidal crescent, located below the disk with inferonasal and temporal extension (black arrows), in a child with Down syndrome and hyperopia. The disk appears equally tilted in this case. (h) Tilted and torted optic disk of a child with Down syndrome with myopic astigmatism. A choroidal crescent is evident below the disk (black arrows) along with a large zone of temporal peripapillary atrophy (white arrow). Note the bean-shaped optic disk in this case. (i) A smaller choroidal crescent, located below the disk and nasally, in a child with Down syndrome and hyperopia. In the upper and central rows, the optic disks have no physiological cupping. Reprinted from Postolache 2019 with permission from Frontiers.