Analysis and Treatment of Axial Ametropic AnisPmetropia

ABSTRACT

Anisometropia is caused by axial ametropia and refractive ametropia. Almost all anisometropia in children are known to be caused by axial ametropia. Axial ametropic anisometropia is corrected by the spectacles by Knapp's rule. We experienced 41 patients with anisometropia, in whom the relationship between the difference in axial length in each eye(x) and the difference in refractive error in each eye(y) was linear, y = -0.00758+2.18554x. According to this approximate regression formula, 27 patients(66%) showed axial ametropic anisometropia and 14 patients(34%) showed refractive ametropic anisometropia. Twenty three(85%) out of 27 patients had had amalyopia. Ten patients(83%) at the age of 9 or less improved their visual acuity after amblyopia treatment, but only 4 patients(36%) older than 9 showed mild improvement. In authors' experience, axial ametropic anisometropia can be corrected by spectacles with full amount of refractive error and by proper amblyopia treatment. It is important to diagnose and treat the axial ametropic anisometropia in early childhood, however even in the patients older than 9 years old the visual prognosis is not so hopeless if treated with fully corrected spectacles and proper amblyopia treatment.