title: Critical age of botulinum toxin treatment in essential infantile esotropia.
abstract: OBJECTIVE
  To assess the results of botulinum toxin treatment in 60 consecutive children with essential infantile esotropia.
  
  
  METHODS
  Bilateral simultaneous injection of botulinum toxin into the medial rectus muscle was performed in 60 patients under direct visualization with an "open sky" technique. Fluothane/sevoflurane insufflation anesthesia was used. Each patient underwent a single bilateral botulinum toxin injection. Patient age at the time of injection ranged from 5-8 months.
  
  
  RESULTS
  Mean patient age at the time of treatment for the 88% of patients who gained a good alignment (within +10 prism diopters [delta] of residual esotropia) was 6.5 months, while mean patient age at time of injection for the 12% of patients who were undercorrected or the deviation relapsed was 7.8 months. Follow-up averaged 5.2 years (range: 2-9 years, SD 2). No variation of the angle of strabismus was observed after 6 months from injection. In some patients with hyperopic refraction, plus lens corrections were prescribed during follow-up to stabilize the alignment.
  
  
  CONCLUSIONS
  Botulinum toxin can be effective in essential infantile esotropia when children are treated by age 7 months.
authors.affiliation: Eye Service, University of Bologna School of Medicine, Italy.
authors.forename: E C
authors.initials: EC
authors.lastname: Campos
authors.forename: C
authors.initials: C
authors.lastname: Schiavi
authors.forename: C
authors.initials: C
authors.lastname: Bellusci
mesh_terms: D000367:Age Factors; D018726:Anti-Dyskinesia Agents / Q000627:therapeutic use*; D001905:Botulinum Toxins / Q000627:therapeutic use*; D004948:Esotropia / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007223:Infant; D007267:Injections; D008297:Male; D009801:Oculomotor Muscles / Q000187:drug effects*; D016896:Treatment Outcome; D015348:Vision, Binocular
chemical_list: D018726:Anti-Dyskinesia Agents; D001905:Botulinum Toxins