Case Reports

Bilateral corneal ectasia 3 years after small incision lenticule extraction (SMILE)

Case Report Details

First Author: F.Aguilera MEXICO

Co Author(s):    C. Hernandez   A. Zapata   A. Pando   M. Benedetti           

Abstract Details

Purpose:

To describe a bilateral corneal ectasia after a 3 year follow up in a patient that underwent a SMILE procedure in our hospital. Small incision lenticule extraction (SMILE) is an alternative that had demonstrated fewer dry eye symptoms, lack of flap related complication, minor damage to the sub basal nerve plexus and less probability of ectasia because it preserves the collagen network in the anterior stroma which represents 60% of the tensile strength, leading to small changes in the biomechanical properties of the cornea. However, there are some reports of ectasia after SMILE in the literature.

Setting:

APEC Hospital, Mexico City, Mexico

Report of Case:

22-year-old, male patient came to our clinic requesting refractive surgery. His manifest refraction was -4.50 -3.50 X 10 in the right eye and -4.25 -3.25 X 174 in the left eye, and the corrected visual acuity was 20/20 in both eyes. A complete ophthalmologic evaluation was unremarkable and Scheimpflug-based corneal topography of both eyes showed maximum keratometry of 45.8 D in the right eye and 46 D in the left eye with a thinnest pachymetry of 511 microns and 514 microns respectively . No abnormalities where shown in the anterior and posterior elevation maps. The Belin-Ambrosio display was unremarkable in the right eye with a final D of 1.06, and in the left eye the pachymetric progression index was marked in yellow, with a final D of 1.80. SMILE was performed without any eventualities with a cap thickness (CT) of 110 µm, cap diameter of 7.50mm, an optical zone of 6.40mm with an incision of 3.5 mm at 120 degrees in both eyes, with a maximum lenticule thickness (LT) of 127 microns for the right eye and 121 microns in left eye, leaving residual stromal bed of 274 and 283 µm respectively. On the first postoperative day the patient's visual acuity was 20/30 right eye and 20/40 in the left eye and a best corrected visual acuity (BCVA) of 20/20, interface with edema in both eyes. Corneal Topographies were performed at the first month postoperatively without signs of ectasia. Patient returns after 3 years without a follow up consultation referring decreased visual acuity of left predominance. BVCA was 20/30 and 20/100 respectively. Corneal topography was performed with signs of ectasia in both eyes, more evident in the left eye. I At this time epi-off corneal crosslinking (CXL) is indicated to prevent progression of corneal ectasia in both eyes.

Conclusion/Take Home Message:

The conclusion in our case its that no procedure is free from adverse effects even in a safe proven procedure as SMILE. We need to use all the tools that are available for predicting a negative or positive outcome on the short and long therm for a patient that will undergo a refractive procedure and the impact that will have on the patients life.

Financial Disclosure:

None