Factors Influencing Astigmatic Correction Using Small-Incision Lenticule Extraction: A Systematic Review and...

Area of Science:

• Ophthalmology
• Refractive Surgery
• Biomedical Engineering

Background:

• Astigmatism correction is a key goal in refractive surgery.
• Small Incision Lenticule Extraction (SMILE) is an advanced laser vision correction procedure.
• Understanding factors influencing SMILE's efficacy in astigmatism correction is crucial.

Purpose of the Study:

• To systematically review the effectiveness of SMILE for astigmatism correction.
• To identify key factors influencing the outcomes of SMILE-based astigmatism correction.

Main Methods:

• Systematic literature review across eight databases.
• Comparison of pre- and post-SMILE refractive astigmatism parameters.
• Assessment of bias using established quality assessment tools.

Main Results:

• SMILE effectively corrects low, moderate, and high astigmatism.
• Elevated ocular residual astigmatism (ORA) correlated with increased postoperative residual astigmatism and index of success.
• Correction outcomes were influenced by ocular rotation, astigmatism characteristics, and patient age.

Conclusions:

• SMILE is effective for various degrees of astigmatism.
• High ORA patients may experience undercorrection, highlighting the importance of vector planning.
• Accurate astigmatism correction with SMILE necessitates careful preoperative planning.