Being Who "Smile" Last !

to describe a case of refractive surprise after uneventful SMILE surgery

a private high-volume specialized ophthalmic center, Baghdad, Iraq

A 23 years old male patient underwent bilateral SMILE refractive surgery for his job requirements. Preoperative refraction was OD -1.5 / -4.5 x 30 (6/12), OS -0.5 / -5.5 x 160 (6/12). Postoperatively he presented with blurred vision in his left eye only. The refraction was 0 /-4.0 x 155 (6/12). A tomography showed inferior steepness of >5D compared to superior keratometry. A differential diagnosis of post-SMILE ectasia or a treatment decentration was formulated. Review of the case including surgery video recording revealed improper centration of the treatment due to poor fixation. The diagnosis  of ectasia was dismissed taking into account the pattern of keratometry change,  no posterior elevation changes, stability of refraction, and OCT epithelial thickness profile. Treatment options (glasses, CL and laser) were reviewed with the patient. A decision was made to use topography-guided PRK using Zeiss Mel-90 excimer laser which resulted in recentration of treatment, topographic regulrization, and improvement of refraction to +0.5/-0.75 x 160 (6/9+). The patient was very satisfied with the outcome.

Decentrations after SMILE surgery are rare. A preventive strategy is important including proper operative techniques, encouraging good patient fixation through verbal control, and verifying angle kappa magnitude and direction.  If decentration is suspected, it must be differentiated from post-SMILE ectasia based on onset and progression of symptoms/findings, in addition to tomographic and OCT epithelial findings. Topography-guided PRK is a useful option to treat gross decentrations and regain excellent visual quality.