Does Frontalis Sling Surgery for Congenital Ptosis Change the Corneal Topography and Refractive Characteristics...

To evaluate the effect of frontalis sling surgery for congenital ptosis on corneal curvature and refractive status.

Prospective study of 60 eyes of 48 patients with severe simple congenital ptosis who underwent surgical correction by frontalis sling surgery. Assessment was done pre-operatively and at 1 week, 1 month, 3 months post-operatively by computerized topographer (Shipp Nippon, CT 1000), IOL master (Carl Zeiss, 500), autorefractometer (Unicos URK-800) and AS-OCT (Cirrus HD-OCT). The results were statistically evaluated to analyze any change in visual acuity, refractive status, keratometry, astigmatism and central corneal thickness (CCT).

Three months post-operatively, significant reduction of cylindrical power by -0.358 D was observed by refraction with corresponding improvement of mean BCVA by 0.24±0.04 logMAR. Corneal topography showed reduction in astigmatism by -0.47±0.95 D; however, the average keratometry did not undergo a significant change. The mean values of astigmatism by IOL master and topographer were comparable. There was significant steepening of the previously flatter meridian (horizontal meridian, in 63.3% patients) while the steeper meridian remained relatively unchanged. A greater reduction in astigmatism was noticed in children in the age group of 5-10 years.

Ptosis surgery modifies the corneal curvature, restoring corneal symmetry and reducing astigmatism; thus changing the refractive status of the patient, which needs to be addressed post-operatively to improve the quality of vision. Children with severe ptosis may benefit from being operated at an early age to achieve better astigmatic reduction.