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Published on: October 18, 2024
Refractive Outcomes After Phototherapeutic Refractive Keratectomy for Granular Corneal Dystrophy
Tomoaki Nakamura1, Takahiro Kataoka1, Takashi Kojima1,2
1Nagoya Eye Clinic, Nagoya, Japan.
Purpose:
This retrospective study aimed to evaluate the effectiveness of a novel procedure named phototherapeutic refractive keratectomy (PTRK), which is a sequential procedure composed of phototherapeutic keratectomy ablation for removal of opacities, followed by smoothing ablation for reducing the corneal surface irregularities and photorefractive keratectomy ablation for correcting refractive errors in eyes with primary granular corneal dystrophy.
Methods:
Twenty-three eyes of 17 patients with granular corneal dystrophy were treated with PTRK. Preoperative and postoperative visual acuity, corneal topography, and changes in spherical equivalent and cylindrical refraction were examined and analyzed.
Results:
The mean spherical equivalent power changed from -0.11 ± 1.36 diopters (D) to 0.19 ± 0.91 D postoperatively (P = 0.121). The change in the mean spherical equivalent was +0.30 ± 0.99 D. The mean preoperative uncorrected distance visual acuity (logMAR) of 0.40 ± 0.26 significantly improved to 0.075 ± 0.145 at 3 months after PTRK (P < 0.001). The mean preoperative corrected distance visual acuity (logMAR) of 0.18 ± 0.17 significantly improved to -0.02 ± 0.11 at 3 months after PTRK (P < 0.01). The surface regularity index was significantly decreased from 0.93 ± 0.46 preoperatively to 0.60 ± 0.30 postoperatively (P < 0.001).
Conclusions:
Our results showed that PTRK could improve corneal surface irregularities and remove opacities. Furthermore, both corrected visual acuity and uncorrected visual acuity improved by the addition of refractive correction. PTRK is a promising surgical procedure for improving postoperative quality of life with a high degree of patient satisfaction.
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