Comparison Of Oblique Astigmatic Outcome In Patients Treated For Myopia With Keratorefractive Lenticule Extraction (Smile) Vs. Implantable Collamer Lens (Icl)
Published 2025 - 43rd Congress of the ESCRS
Reference: FP30.15 | Type: Free paper | DOI: 10.82333/g8hk-b132
Authors: Sawako Kotari 1 , Tadashiro Saeki 1 , Takahiko Hayashi* 1 , Hiroshi Aso 2 , Harumasa Yokota 3 , Kentaro Yuda 4 , Jack Parker 5 , Satoru Yamagami 1 , Richard Mackool 6
1Department of Ophthalmology, Department of Visual Sciences,Nihon University School of Medicine,Tokyo,Japan, 2Department of Ophthalmology, Department of Visual Sciences,Nihon University School of Medicine,Tokyo,Japan;Aso Eye Clinic,Tokyo,Japan, 3Department of Ophthalmology,Asahikawa Medical University,Hokkaido,Japan, 4Kikuna Yuda Eye Clinic,Kanagawa,Japan, 5Parker Cornea,Alabama,United States, 6The Mackool Eye Institute,New York,United States
Purpose
The aim of this study was to compare postoperative corneal astigmatism and spherical equivalence outcomes between SMILE (Small Incision Lenticule Extraction) and ICL (Implantable Collamer Lens) in patients with oblique astigmatism. Oblique astigmatism is generally considered more challenging to treat compared to orthogonal astigmatism. Patients with astigmatism between 15°–75° or 105°–165° were classified as having oblique astigmatism. To avoid potential bias caused by monovision, patients over the age of 38 were excluded.
Setting
This study was conducted at a private single-center eye clinic in Munich, Germany, specializing in refractive surgery. All procedures were performed by experienced refractive surgeons. Patients were selected based on strict inclusion criteria to minimize confounding factors, including the exclusion of those with corneal pathologies or prior ocular surgeries.
Methods
A total of 155 patients (155 eyes per group) were analyzed after 1:1 matching for preoperative sphere and cylinder values within a tolerance of ±0.5 D. All patients underwent refractive follow-up at least six weeks postoperatively. Statistical analysis was performed using SPSS for Windows (version 29.0.2.0), with normality assessed by the Kolmogorov-Smirnov test and group differences analyzed using the Mann-Whitney U test.
SMILE procedures were performed using the VisuMax 800 femtosecond laser (Carl Zeiss Meditec AG). ICL implantation was performed with the EVO+ ICL™ (STAAR Surgical®).
Results
Postoperative outcomes showed that 89.7% of patients in both groups achieved a residual astigmatism of less than -0.75 D. A residual astigmatism of less than -0.25 D was achieved in 39% of the ICL group and 14% of the SMILE group. Postoperative cylinder was significantly lower in the ICL group compared to the SMILE group (p < 0.001). The postoperative median cylinder was -0.5 D in both groups (ICL: -0.75 D to -0.25 D; SMILE: -0.75 D to -0.5 D). Preoperative cylinder ranged from -0.75 D to -4.0 D. Although significant differences were found in postoperative refractive parameters, no significant difference was observed in uncorrected visual acuity (UCVA) between the groups (p = 0.4). The postoperative median UCVA was 1.0 in both groups.
Conclusions
Although Smile and ICL demonstrate significant differences in postoperative refractive parameters for oblique astigmatism, uncorrected visual acuity is comparable between the groups. This suggests that the clinical relevance of these differences is limited. Both procedures are effective treatment options for patients with oblique astigmatism.