title: Instability of ocular alignment in childhood esotropia.
abstract: OBJECTIVE
  Instability of ocular alignment may cause surgeons to delay surgical correction of childhood esotropia. The authors investigated the stability of ocular alignment over 18 weeks in children with infantile esotropia (IET), acquired nonaccommodative esotropia (ANAET), or acquired partially accommodative esotropia (APAET).
  
  
  METHODS
  Prospective, observational study.
  
  
  METHODS
  Two hundred thirty-three children aged 2 months to less than 5 years with IET, ANAET, or APAET of less than 6 months' duration.
  
  
  METHODS
  Ocular alignment was measured at baseline and at 6-week intervals for 18 weeks.
  
  
  METHODS
  Using definitions derived from a nested test-retest study and computer simulation modeling, ocular alignment was classified as unstable if there was a change of 15 prism diopters (PD) or more between any 2 of the 4 measurements, as stable if all 4 measurements were within 5 PD or less of one another, or as uncertain if neither criteria was met.
  
  
  RESULTS
  Of those who completed all 3 follow-up visits within time windows for analysis, 27 (46%) of 59 subjects with IET had ocular alignment classified as unstable (95% confidence interval [CI], 33%-59%), 20% as stable (95% CI, 11%-33%), and 34% as uncertain (95% CI, 22%-47%). Thirteen (22%) of 60 subjects with ANAET had ocular alignment classified as unstable (95% CI, 12%-34%), 37% as stable (95% CI, 25%-50%), and 42% as uncertain (95% CI, 29%-55%). Six (15%) of 41 subjects with APAET had ocular alignment classified as unstable (95% CI, 6%-29%), 39% as stable (95% CI, 24%-56%), and 46% as uncertain (95% CI, 31%-63%). For IET, subjects who were older at presentation were less likely to have unstable angles than subjects who were younger at presentation (risk ratio for unstable vs stable per additional month of age, 0.85; 99% CI, 0.74-0.99).
  
  
  CONCLUSIONS
  Ocular alignment instability is common in children with IET, ANAET, and APAET. The impact of this finding on the optimal timing for strabismus surgery in childhood esotropia awaits further study.
  
  
  BACKGROUND
  The author(s) have no proprietary or commercial interest in any materials discussed in this article.
authors.affiliation: Jaeb Center for Health Research, 15310 Amberly Drive, Suite 350, Tampa, FL 33647, USA. PEDIGETS1Combined@jaeb.org
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Christiansen
authors.forename: Danielle L
authors.initials: DL
authors.lastname: Chandler
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Holmes
authors.forename: Robert W
authors.initials: RW
authors.lastname: Arnold
authors.forename: Eileen
authors.initials: E
authors.lastname: Birch
authors.forename: Linda R
authors.initials: LR
authors.lastname: Dagi
authors.forename: Darren L
authors.initials: DL
authors.lastname: Hoover
authors.forename: Deborah L
authors.initials: DL
authors.lastname: Klimek
authors.forename: B Michele
authors.initials: BM
authors.lastname: Melia
authors.forename: Evelyn
authors.initials: E
authors.lastname: Paysse
authors.forename: Michael X
authors.initials: MX
authors.lastname: Repka
authors.forename: Donny W
authors.initials: DW
authors.lastname: Suh
authors.forename: Benjamin H
authors.initials: BH
authors.lastname: Ticho
authors.forename: David K
authors.initials: DK
authors.lastname: Wallace
authors.forename: Richard Grey
authors.initials: RG
authors.lastname: Weaver
mesh_terms: D002675:Child, Preschool; D004948:Esotropia / Q000503:physiopathology* / Q000601:surgery; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009801:Oculomotor Muscles / Q000503:physiopathology* / Q000601:surgery; D013508:Ophthalmologic Surgical Procedures; D011446:Prospective Studies; D015348:Vision, Binocular / Q000502:physiology*