24 June 1993 Pre- and postoperative optical resolution of the cornea: a preliminary report
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Proceedings Volume 1877, Ophthalmic Technologies III; (1993) https://doi.org/10.1117/12.147557
Event: OE/LASE'93: Optics, Electro-Optics, and Laser Applications in Scienceand Engineering, 1993, Los Angeles, CA, United States
The effect of novel refractive surgical techniques on visual acuity and contrast sensitivity is normally determined by the outcome of human clinical trials. For example, ArF laser photorefractive keratoplasty follows an algorithm based on the patient's preoperative data for keratometry, refraction, pachometry, and ocular length all measured with ultrasound. A normalized ablation rate (which is function of the laser fluence), and the desired refractive correction are then used to calculate the ablation depth. On the day of surgery, the epithelium is mechanically removed and the bare cornea photoablated. Finally, the cornea may be medicated with a topical application of antibiotics and the eye is patched. On postoperative day 7, the epithelium is healed and visual acuity and keratometry are measured. With PRK, the theoretical outcome refraction should be within +/- 0.25 D. Thus far however, reproducibility is only of +/- 2 D. We believe the large discrepancy between theory and practice is due to several parameters that vary patient-to-patient.
© (1993) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jean-Marie A. Parel, Gabriel Simon, Pascal O. Rol, Qiushi Ren, and William E. Lee "Pre- and postoperative optical resolution of the cornea: a preliminary report", Proc. SPIE 1877, Ophthalmic Technologies III, (24 June 1993); doi: 10.1117/12.147557; https://doi.org/10.1117/12.147557

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