Long-term results of multizone photorefractive keratectomy for myopia of -6.0 to -10.0 diopters.

Abstract

PURPOSE:

To evaluate the 4 year refractive outcome of multizone photorefractive keratectomy (PRK) in eyes with high myopia.

SETTING:

++SSK Okmeydani Education Hospital, Eye Clinic, Türkiye Hospital, Okmeydani, Istanbul.

METHODS:

Three ablation zones were used in 92 eyes of 48 patients whose refractive errors were between -6.0 and -10.0 diopters (D) (mean spherical equivalent -7.42 D +/- 1.25 [SD]). The zones were between 4.5 and 6.0 mm based on the thickness of the cornea and the refractive correction. After the epithelium healed, dexamethasone was applied 4 times a day during the first postoperative week and then fluorometholone was applied 4 times a day for a minimum of 4 weeks. If hyperopia was found post-PRK, the steroid dose was gradually tapered. The patients were examined 1 and 3 days postoperatively, 1, 2, and 4 weeks, every 3 months for the first year, and then every 6 months.

RESULTS:

All patients were overcorrected in the first postoperative week. At 2 and 3 weeks, the mean manifest refraction was closer to emmetropia. At 6 months, the refraction was stable. The mean spherical equivalent was -0.10 D at the end of the first year, and stabilization continued for 4 years. After the third month, the haze regressed gradually without requiring treatment. In 1 patient, herpes simplex keratitis developed and healed in a short time with topical antiviral therapy. Nineteen eyes regressed more than -1.0 D, 4 eyes were overcorrected, 4 eyes had central islands (at 6 months), and 2 eyes were undercorrected. Two eyes were retreated for regression; 1 eye was retreated for undercorrection and 1 eye, for central island. An uncorrected visual acuity of 20/40 or better was achieved in 79.2% of eyes, and 73.9% were within +/-1. 0 D of the intended correction.

CONCLUSION:

++Photorefractive keratectomy was effective in treating high myopia between -6.0 and -10.0 D. The induced refractive changes stabilized between 6 and 9 months. In most patients, no significant regression was found after this period.

• Authors: H K Keskinbora
• Journal: Journal of cataract and refractive surgery (J Cataract Refract Surg) Vol. 26 Issue 10 Pg. 1484-91 (Oct 2000) ISSN: 0886-3350 [Print] United States
• PMID: 11033395 (Publication Type: Comparative Study, Journal Article)

Topics

• Adult
• Cornea (physiopathology, surgery)
• Female
• Follow-Up Studies
• Humans
• Lasers, Excimer
• Male
• Middle Aged
• Myopia (physiopathology, surgery)
• Photorefractive Keratectomy (methods)
• Prognosis
• Refraction, Ocular
• Retrospective Studies
• Visual Acuity