To investigate the influence of unilateral congenital ptosis on the development of the eye and vision in children.
In this prospective observational study, 41 patients with unilateral congenital ptosis were enrolled (age range 3-15y). The blepharoptosis was divided into 3 subgroups according to the margin reflex distance-1 (MRD-1), including mild group (MRD-1≥2 mm), moderate group (0≤MRD-1<2 mm), and severe group (MRD-1<0 mm). The fellow eyes served as controls. All subjects underwent ocular examinations, including axial length, keratometry, and refractive error.
The incidence of astigmatism (ptotic eyes: 58.5% fellow eyes: 24.4%, =0.002) and magnitude of cylindrical power (ptotic eyes: -0.86±0.79 D fellow eyes: -0.43±0.63 D, =0.003) differed significantly between the ptotic eyes and the fellow eyes. The spherical equivalent refraction (=0.006), spherical power (=0.01), cylindrical power (=0.011), axial length-corneal radius (AL/CR) ratio (=0.009), frequency of hyperopia (=0.002) and astigmatism (=0.004) were significantly different among the ptotic eye subgroups and the fellow eye group. In addition, in patients with congenital ptosis, the incidence of amblyopia is 43.9% and the incidence of anisometropia is 24.4%. More importantly, the ratio of AL/CR showed significantly positive correlation with the severity of ptosis (=0.002).
Congenital ptosis may lead to a delayed eyeball development in the aspect of AL/CR. The risk of amblyopia is also increased due to visual deprivation and aggravated anisometropia, particularly in severe ptosis case.

International Journal of Ophthalmology Press.