Abstract
Abstract: :
Purpose: To evaluate the long–term outcomes of Thiel–Behnke corneal dystrophy treated by simultaneous phototherapeutic keratectomy (PTK) with photorefractive keratectomy (PRK) Methods: Four patients with Thiel–Behnke corneal dystrophy and refractive errors were treated by PTK with PRK over 3 years. Three of the 4 patients belong to a same family. Six eyes of the 4 patients were treated by combined PTK and PRK at the same time. To compensate the post–PTK hyperopic shift, the target spherical equivalent of PRK was set as 2 D under–treatment. Pre– and post–operation visual acuities (VA) and refractive status were compared, and the symptoms and signs of recurrent corneal erosions were recorded. Results: Five of 6 eyes got improved VA significantly (≥3 lines) at 6 months, 6 eyes at 1year, and 5 eyes at 3 years postoperatively. Two eyes had improved best spectacle–corrected VA (BSCVA) significantly at 6 months, 1 eye at 1 year, and 2 eyes at 3 years postoperatively. The mean total spherical equivalent change was 4.94±2.08 D (2.75–8.125 D) at 1 year, and 4.21±2.47 D (1.375–7.875 D) at 3 years postoperatively. The mean modified spherical equivalent change (total spherical equivalent change – spherical equivalent correction by PRK) was 1.54±1.06 D (0.375–3 D) at 1 year, and 0.81±1.09 D at 3 years postoperatively. There are 2 eyes with recurrent corneal erosions over 5 years after treatment. Recurrent honeycomb appearance at anterior stroma occurred gradually at all 6 eyes about 2 to 3 years after the procedure. Conclusions: Simultaneous PTK with PRK can provide an alternative and refraction–predictable treatment for patients with Thiel–Behnke corneal dystrophy and refractive errors. Although recurrence of the disease cannot be avoided by this procedure after a long–term follow–up, the need of penetrating keratoplasty can be delayed and symptoms associated recurrent corneal erosions can be relieved for a few years.
Keywords: refractive surgery: PRK • visual acuity • refraction