Eyeworld

EW REFRACTIVE SURGERY 54 August 2015 Elizabeth Hofmeister, MD, highlighted the best refractive papers at the "Hot Off the Press" session at the 2015 ASCRS•ASOA Symposium & Congress. The papers were chosen from the Best Paper of Session winners. Here are the abstracts from the studies, with Dr. Hofmeister's comments regarding selection. Prospective randomized controlled trial comparing optical quality after myopic small-incision lenticule extraction, LASIK, and PRK: Impact on binocular vision Pravin K. Vaddavalli, MD, and colleagues Purpose: This randomized con- trolled study addresses two import- ant questions related to visual per- formance of myopic eyes following refractive surgery. Firstly, to compare the optical quality following bilat- eral refractive surgery and secondly, to compare the impact of induced ocular aberrations on sensory and motor visual performance following different refractive surgeries. Methods: A total of 106 patients with myopic astigmatism were ran- domized to undergo either femtosec- ond LASIK (40), SMILE (40), or PRK (26). PRK and LASIK were performed on the Technolas 217z excimer laser platform (Bausch + Lomb, Bridgewa- ter, N.J.), and SMILE (small-incision lenticule extraction, Carl Zeiss Med- itec, Jena, Germany) was performed on the VisuMax femtosecond laser system (Carl Zeiss Meditec). Preop- erative and postoperative 1 week, 1 month, 3 months, and 6 months was analyzed. The main outcomes reported in this study were best corrected high contrast and low contrast acuity, manifest objec- tive refraction, ocular aberrations measured using the IMAGINE EYES irx3 aberrometer (Orsay, France) and stereopsis using random dot stereo- acuity. Retinal image quality was compared among three categories before and after surgery using image quality metrics. Results: At 6 months postop, the spherical equivalents were +0.14±0.05, +0.37±0.03, +0.02±0.01 in the LASIK, PRK, and SMILE groups respectively (p>0.001). High contrast unaided distance acuity (UDVA) was comparable across the groups, while low contrast UDVA de- creased in both LASIK and PRK (0.1 vs. 0.2) and it was better following SMILE (0.1 vs. 0.0). Higher-order aberrations increased significantly in PRK (0.25±0.02 µ vs. 0.6±0.03 µ, p<0.001) and LASIK (0.27±0.01 µ vs. 0.6±0.02 µ, p<0.001) but were not significantly different following SMILE (0.24±0.3 µ vs. 0.28±0.4 µ, p=0.11). Stereoacuity was significant- ly better after SMILE (49.39±5.49 vs. 19.90±1.72 sec arc, p<0.001) but showed a decrease following LASIK (45.55±3.28 vs. 55.72±1.75 sec arc, p<0.05) and PRK (47.05±3.95 vs. 64.02±2.43 sec arc, p<0.01). Conclusion: LASIK, PRK, and SMILE resulted in accurate correction of refractive error and comparable high contrast UDVA but low contrast UDVA was reduced to a lesser degree following SMILE. Patients under- going SMILE had lesser induced aberrations and had better stereo- acuity following surgery compared to either LASIK or PRK. Dr. Hofmeister: I chose this paper because it is, to my knowledge, the first head-to-head comparison of mod- ern LASIK and PRK with the SMILE procedure. SMILE is an all-femtosecond corneal refractive procedure that is of great interest to the military because it offers the rapid visual recovery enjoyed by LASIK patients and practically eliminates the future risk of traumatic flap dislocation. However, the visual results from initial SMILE trials did not approach the rates of 20/20 or better uncorrected vision that we are used to with advanced-profile LASIK. Dr. Vaddavalli's study is the first to show that SMILE can hold its own against Hot off the press: First in a series of 5 presentations Scan to watch video!

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