title: Optic nerve hypoplasia and small eyes in presumed amblyopia.
abstract: OBJECTIVE
  To assess the anatomy of eyes presumed to be amblyopic and their fellow eyes.
  
  
  METHODS
  Two hundred seventy-five patients diagnosed with amblyopia and 88 healthy or glaucomatous subjects.
  
  
  METHODS
  All subjects underwent complete examinations, including cycloplegic refraction, slit lamp examination, ophthalmoscopy, and retinal imaging. Axial lengths were determined on 263 amblyopic and 88 healthy and glaucomatous subjects by ultrasonic biometry.
  
  
  METHODS
  Optic disc areas were determined by magnification correction of disc images performed with formulas. Dysversion of the optic disc was determined by simultaneous viewing of disc photographs, digitized images of both eyes, or both.
  
  
  RESULTS
  The mean disc area of eyes presumed to be amblyopic was 1.72 mm(2) +/- 0. 73 SD and 1.95 mm(2) +/- 0.69 SD for nonamblyopic eyes (P =.0017). The mean disc area for 176 optic discs of glaucomatous and healthy eyes was 2.61 mm(2) +/- 0.95 SD. The mean axial length for eyes in the general population is 23.65 mm +/- 1.35 SD. The healthy and glaucomatous group in this study had a mean axial length of 23.89 mm +/- 1.29 SD. The eyes with poorer vision that were assumed to be amblyopic averaged 22.42 mm +/- 2.01 SD in length, whereas their nonamblyopic fellow eyes averaged 22.83 mm +/- 1.89 SD (P =.022). The differences between eyes in the healthy population and eyes that are presumably amblyopic, as well as the healthy and fellow eyes, are highly significant (P <.0001)(7.0 x 10(-16)).
  
  
  CONCLUSIONS
  Vision impairment in presumed amblyopia is associated with optic nerve hypoplasia with relative microphthalmos, which is more notable in those eyes with poorer vision.
authors.affiliation: Department of Physiology, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA. lemp1871@aol.com
authors.forename: P
authors.initials: P
authors.lastname: Lempert
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000550:Amblyopia / Q000175:diagnosis / Q000209:etiology*; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D006801:Humans; D008850:Microphthalmos / Q000150:complications*; D008875:Middle Aged; D009896:Optic Atrophy / Q000150:complications* / Q000151:congenital / Q000175:diagnosis; D009898:Optic Disk / Q000002:abnormalities* / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D014463:Ultrasonography; D014792:Visual Acuity