title: [Stereoacuity before and after operation of Parks shift of neutral zone in children with congenital nystagmus].
abstract: OBJECTIVE
  To evaluate thestereoacuity before and after operation of Parks shift of neutral zone in children with congenital nystagmus.
  
  
  METHODS
  Using Yan's synoptophore random-dot stereograms and near stereoacuity chart, preoperative measurement of distance and near stereoacuity in primary gaze position and neutral zone were qualitatively and quantitatively determined in 21 children with congenital nystagmus. After Parks shift of neutral zone, streroacuity measurement was evaluated by the similar method. The grade of stereoacuity before and after operation was analyzed.
  
  
  RESULTS
  Nystagmus was disappeared or obviously relieved in the primary gaze position, vision was improved 2 - 5 lines, and compensatory head posture was eliminated or improved after operation in 21 cases. The stereoacuity was gradually improved from 800 to 60 seconds of arc, peripheral to macular stereoacuity, and even foveal stereoacuity.
  
  
  CONCLUSIONS
  Children with congenital nystagmus may partly have stereoscopic vision. The stereoscopic vision in neutral zone may be better than in non-neutral zone. The nystagmus, compensatory head posture, and distance and near stereoscopic vision were improved after operation of Parks shift of neutral zone.
authors.affiliation: Department of Ophthalmology, People's Hospital in Jinlin Province, Changchun 130021, China. y60315@sohu.com.cn
authors.forename: Gui-lian
authors.initials: GL
authors.lastname: Cao
authors.forename: Hao-rong
authors.initials: HR
authors.lastname: Xin
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.forename: Shu-xia
authors.initials: SX
authors.lastname: Wang
authors.forename: Ming
authors.initials: M
authors.lastname: Zhang
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
mesh_terms: D002648:Child; D003867:Depth Perception; D005260:Female; D006801:Humans; D008297:Male; D020417:Nystagmus, Congenital / Q000503:physiopathology / Q000601:surgery*; D013508:Ophthalmologic Surgical Procedures