Purpose
To report visual, refractive and topographic outcomes of Small Incision Lenticule Extraction (SMILE) and intrastromal corneal collagen cross-linking in eyes with abnormal topography and/or forme fruste keratoconus.
Methods
Prospective case series of 8 eyes of 4 patients. Inclusion criteria were topographic diagnosis of forme fruste keratoconus and/or irregular corneas, CDVA ≥20/40, stable refraction of at least 1 year, patients aged ≥21 years and expected residual corneal thickness > 400 μm before performing collagen cross-linking. Patients were treated with SMILE followed by intrastromal injection of riboflavin (0.1 ml twice with a 15 minutes gap) inside the pocket. Ultraviolet A light was applied for 30 minutes in each eye. Follow-up was done at day 1, 1 week, 1-3-6 months. Study parameters were UDVA, CDVA, manifest refraction, tomographic and clinical evaluations.
Results
Mean age was 31.25±5.82 yrs. (range 22-36). Mean follow up was 3.00±1.31 months. Mean UDVA (LogMAR) was 1.19±0.29 preoperatively and 0.17±0.12 postoperatively (p<0.001). Mean pre and postoperative CDVA (LogMAR) was 0.03±0.05 and 0.12±0.10, respectively (p=0.065). Preoperative SE was -4.50±1.47 D (range -6.25 to -2.75) and postoperative SE was -0.30±0.72 D (range -1.25 to +1.12) (p<0.001). Three eyes lost 1 line of CDVA, 1 eye lost 2 lines and 1 eye lost 3 lines due to haze. All patients presented intrastromal haze that improved during the follow-up. K1 was 42.78±0.83 D preoperatively and 39.91±2.01 D at the last follow-up visit (p=0.005). K2 was 45.81±1.85 D and 42.22±3.66 D pre and postoperatively, respectively (p=0.002). Km was 44.22±0.76 D before surgery and 41.02±2.75 at the last visit (p=0.002).
Conclusions
Combined SMILE and Cross-linking may be a promising treatment option in patients where conventional laser refractive surgery is contraindicated. Further follow-up and larger samples are needed. Despite the fact that the refraction was near plano, 5 eyes lost lines of CDVA due to haze.
Keywords: 574 keratoconus •
682 refractive surgery: other technologies •
479 cornea: clinical science