title: Head tilt-dependent esotropia associated with trisomy 21.
abstract: OBJECTIVE
  To describe a series of patients who used a head tilt to control esotropia.
  
  
  METHODS
  Retrospective noncomparative case series.
  
  
  METHODS
  Seven children with esotropia that decreased with their compensatory abnormal head tilt. Six of the patients had trisomy 21. The patients had no other identifiable etiology for their head tilt, including no oblique muscle dysfunction, nystagmus that changed with head tilt, or uncorrected refractive error.
  
  
  METHODS
  Six patients underwent horizontal extraocular muscle surgery. Preoperative evaluation in 4 patients included assessment of the change in head position with either monocular occlusion or prisms.
  
  
  METHODS
  Ocular alignment in primary position and improvement in abnormal head tilt after surgery.
  
  
  RESULTS
  In the 4 patients who underwent preoperative testing, the abnormal head tilt resolved with either monocular occlusion or prisms. The head tilt and esotropia were eliminated or improved in all patients who underwent strabismus surgery.
  
  
  CONCLUSIONS
  Abnormal head tilt may be used as a compensatory maneuver to improve purely horizontal strabismus. This finding appears to be associated with trisomy 21. Horizontal extraocular muscle surgery may improve the head tilt in such patients.
authors.affiliation: Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis Children's Hospital, One Children's Place, St. Louis, MO 63110, USA. lueder@vision.wustl.edu
authors.forename: Gregg T
authors.initials: GT
authors.lastname: Lueder
authors.forename: Brian
authors.initials: B
authors.lastname: Arthur
authors.forename: David
authors.initials: D
authors.lastname: Garibaldi
authors.forename: Sylvia
authors.initials: S
authors.lastname: Kodsi
authors.forename: Burton
authors.initials: B
authors.lastname: Kushner
authors.forename: Richard
authors.initials: R
authors.lastname: Saunders
mesh_terms: D002675:Child, Preschool; D004314:Down Syndrome / Q000150:complications*; D004948:Esotropia / Q000150:complications* / Q000601:surgery; D005260:Female; D019416:Head Movements; D006801:Humans; D007223:Infant; D008297:Male; D009801:Oculomotor Muscles / Q000601:surgery; D013508:Ophthalmologic Surgical Procedures; D012189:Retrospective Studies