Amblyopic astigmatism characteristics and surgical outcomes in younger children with severe congenital ptosis after frontalis suspension surgery

Background To examine the astigmatism characteristics and surgical outcomes in patients with unilateral severe congenital ptosis following frontalis suspension surgery. Methods We included 53 congenital ptosis patients who underwent frontalis suspension surgery in Hunan Children's Hospital. Each patient underwent a refractive examination before and after surgery to assess astigmatism. We also evaluated the effects and complications associated with the procedure. Results Degree of astigmatism in ptotic and fellow eyes was − 1.45 ± 0.59 D and − 0.66 ± 0.51 D before surgery. Ratio of severe astigmatism in ptotic and fellow eyes was 51.3 and 12.8%. The fellow eyes presented with with-the-rule astigmatism (WR; 71.8%) and against-the-rule astigmatism (AR; 20.5%) types, with no cases of oblique astigmatism (OA). Ptotic eyes demonstrated higher frequencies of AR (59.0%) and OA (10.2%) than did fellow eyes. Furthermore, the former showed increased astigmatism, followed by a gradual decrease at the 6-month, before significantly decreasing at the 1-year postoperatively. The ratio of postoperative AR and OA astigmatism cases in ptotic eyes decreased to 35.9 and 7.7% 1 month postoperatively. However, there was a postoperative increase in the WR ratio from 30.8 to 56.4% after 1 month. Kaplan-Meier survival analysis showed a success rate of 81.4% at 6 months and 62.9% at 12 months which was influenced by the following complications: suture reaction, epithelial keratopathy, infection and granuloma, lid lag, and recurrence. Conclusion Monocular congenital ptosis could develop severe astigmatism and higher frequency of AR or OA, early surgery may ameliorate astigmatic amblyopia.