title: [Myopic regression after photorefractive keratectomy].
abstract: OBJECTIVE
  To investigate myopic regression after excimer laser photorefractive keratectomy (PRK) in patients with myopia.
  
  
  METHODS
  103 eyes with regression (>or= -1.00 D) found in the follow-up for more than 1 year were included in this study. The preoperative spherical equivalent was -4.00 - -14.50 D (-8.72 +/- 2.65 D). Patients were divided into two groups: (1) moderate myopia (-4.00 - -7.90 D) and (2) high myopia (>or= -8.00 D).
  
  
  RESULTS
  A significant positive correlation was found between regression and the extent of attempted correction, the rate of regression in high myopia group was 6.93% and that in moderate group, 1.17%. The rate of regression in older age group was higher than that in younger cases. (P < 0.01). Relatively severe haze under the corneal epithelium often accompanies the regression, and decrease of the dosage of topical corticosteroid application or its withdrawal because of the development of corticosteroid ocular hypertention could lead to the regression. The stability of the refraction is not related to the difference in sex. The regression is often accompanied by the increase in K value.
  
  
  CONCLUSIONS
  The regression is significantly related to the extent of attempted correction, patients' age, corneal haze and topical application of corticosteroid.
authors.affiliation: Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730.
authors.forename: G
authors.initials: G
authors.lastname: Pang
authors.forename: S
authors.initials: S
authors.lastname: Zhan
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.forename: Y
authors.initials: Y
authors.lastname: Jin
authors.forename: Y
authors.initials: Y
authors.lastname: Sun
authors.forename: W
authors.initials: W
authors.lastname: Li
mesh_terms: D000305:Adrenal Cortex Hormones / Q000009:adverse effects; D000328:Adult; D000367:Age Factors; D005260:Female; D006801:Humans; D054018:Lasers, Excimer; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000601:surgery*; D018903:Photorefractive Keratectomy / Q000009:adverse effects*; D011183:Postoperative Complications / Q000209:etiology; D012029:Refraction, Ocular; D012189:Retrospective Studies; D012737:Sex Factors; D014792:Visual Acuity
chemical_list: D000305:Adrenal Cortex Hormones