Hyperopic anisometropia with a shorter axial length ipsilateral to the ptotic eye in children with congenital ptosis

BACKGROUND: To investigate the clinical characteristics of children with congenital ptosis, with particular attention given to the incidence of anisometropia, and the difference in axial length (AL) between the right and left eyes. METHODS: The medical charts of 55 patients with congenital ptosis at Niigata University Medical and Dental Hospital were retrospectively analyzed. Clinical characteristics, including age, cycloplegic refraction, AL, and the presence of amblyopia and its causes were analyzed. RESULTS: Age at the initial visit was 16 ± 20 (mean ± standard deviation, the same applies below) months. Of the 49 patients whose cycloplegic refraction was measured, hyperopic anisometropia, defined as ≥ one-diopter difference in spherical equivalent (SE), was observed in 1/11, 9/27 and 5/11 patients with bilateral, right, and left ptosis, respectively. Among 14/38 patients with hyperopic anisometropia involving unilateral ptosis, 13 demonstrated a larger SE in the ptotic eye than in the non-ptotic eye. The inter-eye difference in AL (AL of the ptotic eye minus that of the non-ptotic eye) in six patients with unilateral ptosis and hyperopic anisometropia ipsilateral to the ptotic eye (-0.29 ± 0.40 mm) was significantly smaller than that in three patients with unilateral ptosis and no hyperopic anisometropia (0.38 ± 0.29 mm). CONCLUSIONS: At our institute, children with congenital ptosis had a high incidence of hyperopic anisometropia ipsilateral to the ptotic eye. Furthermore, this condition was associated with a shorter axial length. These results indicate that refractive correction for hyperopic anisometropia is important for proper visual development in children with congenital ptosis.