Abstract
Purpose :
To determine the percentage of visually significant decentered treatments in SMILE, and the impact of treatment decentration on patient-reported visual outcomes.
Methods :
A retrospective evaluation of 31 eyes that underwent SMILE over the past year was conducted. Treatment decentration was determined on both pachymetry difference maps and Scheimpflug anterior tangential curvature difference maps, derived from preoperative and 3-month postoperative maps. Decentration was determined as the vector magnitude from the center of the visual axis, or center of the respective difference map, to the center of treatment. The center of treatment was determined by means of superimposing a schematic of concentric circles with a grid at the center, on the difference maps. The schematic was overlaid such that the treatment zone was best-fit into one of the circles. The center of the grid was taken as the center of treatment.
Results :
Average treatment decentration in all eyes was 0.45 ± 0.24mm based on the pachymetry difference maps, and 0.36 ± 0.16mm based on the anterior tangential curvature difference maps (p=0.005). 22 (70.97%) eyes demonstrated good patient-reported visual outcome, while 9 (29.03%) eyes had suboptimal results, some of which requiring an enhancement surgery. Based on the pachymetry maps, average decentration was 0.45 ± 0.25mm in the group with good visual outcome, and 0.46 ± 0.21mm in the group with suboptimal visual outcome (p=0.8). Based on the anterior tangential curvature maps, average decentration was 0.32 ± 0.16mm in the group with good visual outcome, and 0.43 ± 0.14mm in the group with suboptimal visual outcome (p=0.09).
Conclusions :
The magnitude of treatment decentration in SMILE differs depending on whether decentration is determined using pachymetry maps or anterior tangential curvature maps. The magnitude of decentration, as determined by use of either anterior tangential curvature maps or pachymetry maps, does not differ between eyes with good patient-reported visual outcomes and those with suboptimal outcomes.
This is a 2021 ARVO Annual Meeting abstract.