上皮基底膜ジストロフィー（EBMD）に対するエキシマレーザー光治療角膜形成術（PTK）後の高次収差、角膜密度、および視力
Simon Helm1, Johanna Wiedemann1, Benjamin Rosswinkel2
1Department of Ophthalmology, Faculty of Medicine and University Hospital Cologne, Cologne, Germany.
Background:
To evaluate visual acuity outcome after excimer laser phototherapeutic keratectomy (PTK) for epithelial basement membrane dystrophy (EBMD) and to provide new insights into higher-order aberrations (HOAs) and corneal density changes.
Methods:
In this single-center cohort, 92 eyes from 80 individuals underwent PTK for EBMD, with follow-up durations reaching up to 7.5 years (mean 332 ± 526.5 days).
Results:
Mean BCVA in EBMD improved by 0.17 ± 0.17 logMAR (p < 0.001) for patients without visual acuity limitations and by 0.14 ± 0.31 (p = 0.004) logMAR if patients had additional visual acuity limitations. Refraction remained stable after PTK. HOA reduced by 0.16 ± 0.23 μm (p < 0.001), corneal density by 6.73 ± 11.83 gray scale units (p < 0.001), and K max by 1.02 dpt (±2.73) (p = 0.006) after PTK. A correlation before and after PTK between HOA (p = 0.014 and 0.002), corneal density (p < 0.002), and K max (p = 0.010) with BCVA was observed. Light haze occurred in 10% of the cases. Re-PTK was necessary for 1 patient (1.1%).
Conclusion:
PTK significantly enhances visual acuity in patients with EBMD, independently of additional visual acuity limitations. The significant reduction of HOA, corneal density, and K max as well as the correlation of these parameters with visual acuity prove an effective therapy on an objective level.
