Visual And Refractive Outcomes Of Smile For Myopic Astigmatism Using A Triple Marking Method And Manual Cyclotorsion Compensation In Eyes With Cylinders ≥ -3.00 D

To evaluate the clinical outcomes and long-term safety, efficacy, predictability, and refractive stability following myopic astigmatism correction with SMILE in eyes with cylinders ≥ -3.00 D

Nethradhama Superspeciality Eye Hospital , Bangalore , India

This retrospective study included eyes undergoing SMILE for myopic astigmatism with pre-op cylinders ≥-3.00 D. A nomogram aiming for 15%, 10% and 0% over correction for WTR, oblique and ATR astigmatism was applied. Intra-operatively, cyclotorsion compensation was performed by gentle rotation of the contact glass after marking the cornea with a 3-reference marker (Ganesh bubble marker, Epsilon, USA). The mean post-operative follow-up for was 18.08 months.

Fifty eyes from 50 patients (mean age 29.7±6.35 years) were included.The pre-op mean sphere, cylinder and SE was -2.11±1.68, -3.53±0.46, and -3.87±1.65 D, which reduced to -0.03±0.08, -0.21±0.34, and -0.14±0.23 respectively at 18 months. Ninety- two % and 82 % eyes, respectively, remained within ±0.50 D of manifest SE and cylinder. Eighty % eyes maintained a UDVA of 20/20 or better. Twenty- four % eyes gained 1 or more lines, while no eye lost more than 1 line of CDVA. Safety and Efficacy indices were 1.13 and 1.01 respectively. Vector analysis suggested mean TIA, SIA, AOE and CI values of -3.39±0.43, -3.44±0.51, 1.62±3.23 degrees and 1.01±0.10 respectively. No eye underwent enhancement for significant residual refractive error. 

At 18 months, our results demonstrate good safety, efficacy, predictability, and stability of SMILE for high astigmatism (>-3.00 D cylinder), using a triple marking method, manual cyclotorsion compensation and appropriate nomogram

Financial Disclosure: Dr Sri Ganesh and Dr Sheetal Brar are consultants for Carl Zeiss Meditec