Related Experiment Video
Updated: Dec 1, 2025

Author Spotlight: Advancements in Refractive Surgical Correction for Presbyopia and Exploring Postoperative Visual Acuity
Published on: September 20, 2024
Topography-Guided Custom Ablation Photorefractive Keratectomy Treatment of Irregular Astigmatism Resulting From
Purpose:
To describe the use of topography-guided custom ablation treatment with photorefractive keratectomy (T-CAT PRK) to correct irregular astigmatism and visual aberrations resulting from decentered small incision lenticule extraction (SMILE).
Methods:
Case report and literature review.
Results:
A 41-year-old woman experienced blurred uncorrected distance acuity (UDVA), reduced corrected distance acuity (CDVA), and monocular diplopia in one eye following SMILE due to treatment decentration. Retrospective review of the surgical video provided visual cues to the impending decentration at multiple points during the docking process and lenticule creation. Re-treatment was performed using T-CAT PRK with mitomycin C application with off-label use of the EX500 excimer laser (Alcon Laboratories, Inc). Treatment resulted in improvement in UDVA and CDVA to 20/12; reduced higher order aberrations, particularly vertical coma (-0.65 µm to 0.197 µm); topographic pattern centration; and subjective symptom resolution.
Conclusion:
Recognition of subtle visual cues at the time of SMILE docking can provide critical feedback to avoid treatment decentration. T-CAT PRK can be a useful treatment option when decentration occurs. [J Refract Surg. 2020;36(11):766-771.].
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