Long-term outcome of refractive errors in patients with congenital blepharoptosis who have undergone ptosis surgery

Clinical relevance Ptosis surgery induces some changes in pre-existing refractive errors and astigmatism. Monitoring refractive outcomes, planning of vision rehabilitation, and amblyopia treatment may be required following ptosis surgery. Background The few studies published on the outcomes of refractive error after ptosis surgery have been controversial. The aim of this study was to evaluate long-term outcomes of refractive error in patients with congenital blepharoptosis who had undergone ptosis surgery. Methods Patients with congenital blepharoptosis who had undergone ptosis surgery were enrolled in the study. Data on pre- and post-operative refractive errors, marginal reflex distance 1 (MRD1), and levator function were obtained. The data from fellow eyes were used as the control. Results The mean patient age of patients undergoing ptosis surgery was 19.8 ± 8 years. The mean follow-up time (time between the operation and post-up measurements) was 4.7 ± 2.1 years with a range of 2-10 years. There were no significant differences in mean refractive changes, being 0.53 ± 0.40D vs. 0.36 ± 0.45D in sphere (p = 0.19) and 0.48 ± 0.56 vs. 0.30 ± 0.23 in cylinder (p = 0.17) in operated and control eyes, respectively. Astigmatism change was, however, significantly higher in the operated eyes with an MRD1 change of ≥2.5 mm (0.84 ± 0.66 vs. 0.27 ± 0.39, p = 0.024). The changes in astigmatism in the operated eyes had a significantly positive correlation with the changes of MRD1 (r = 0.497, p = 0.019). Vectorial analysis showed no significant difference between the changes in astigmatism of the operated and control eyes (0.58 *48o vs. 0.45*53o, respectively). Conclusion Spherical power of the eyes of patients with congenital ptosis who undergo ptosis surgery does not change. A significant change in astigmatism can be anticipated in eyes with more than 2.5 mm change in MRD1. There is an association between change in astigmatism and MRD1 following ptosis surgery.