title: The change in ocular refractive components after cycloplegia in children.
abstract: OBJECTIVE
  To study the change in ocular refractive components after cycloplegia in children.
  
  
  METHODS
  Anterior chamber depth, lens thickness, vitreous chamber length, and ocular axial length were measured in 135 Chinese children (270 eyes) before and after cycloplegia. The corneal curvatures of 136 selected eyes were studied before and after cycloplegia with a computerized video keratoscope.
  
  
  RESULTS
  Anterior chamber depth increased (P <.001) while both lens thickness and vitreous chamber length decreased (P <.001) significantly after cycloplegia regardless of the refractive state. However, axial length increased in hyperopic eyes (P =.027) but decreased in myopic eyes (P =.008) after cycloplegia. Mean corneal power of zones 3 mm (MD3, P =.009) and keratometer K1 readings increased (P =.025) in hyperopic eyes, while MD3 (P =.033), K1 (P =.039) and K2 (P =.003) readings decreased in myopic eyes significantly after cycloplegia. Similarly, mean corneal power of zones 5 mm and 7 mm in myopic eyes decreased dramatically (P <or=.001). In both hyperopic and myopic eyes, there was significant difference (P <.001) in the mean value of the upper and lower half of the vertical meridian, as well as the medial and lateral half of the horizontal meridian, respectively.
  
  
  CONCLUSIONS
  Cycloplegia has a great influence on various refractive components in children. There is asymmetry of the corneal surface within the same horizontal or vertical meridian.
authors.affiliation: Department of Ophthalmology, Yantai Yuhuangding Hospital, Affiliated Hospital of Medical College, Qingdao University, Yantai, Shandong Province, Peoples Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Gao
authors.forename: Xuying
authors.initials: X
authors.lastname: Zhuo
authors.forename: Alvin K H
authors.initials: AK
authors.lastname: Kwok
authors.forename: Ning
authors.initials: N
authors.lastname: Yu
authors.forename: Lusheng
authors.initials: L
authors.lastname: Ma
authors.forename: Jinghua
authors.initials: J
authors.lastname: Wang
mesh_terms: D000065:Accommodation, Ocular / Q000502:physiology*; D000293:Adolescent; D000867:Anterior Chamber / Q000502:physiology; D001285:Atropine / Q000008:administration & dosage*; D002648:Child; D002924:Ciliary Body / Q000187:drug effects*; D019781:Corneal Topography; D005260:Female; D006801:Humans; D006956:Hyperopia / Q000150:complications / Q000503:physiopathology; D008297:Male; D009184:Mydriatics / Q000008:administration & dosage*; D009216:Myopia / Q000150:complications / Q000503:physiopathology; D012029:Refraction, Ocular / Q000502:physiology*
chemical_list: D009184:Mydriatics; D001285:Atropine