Biomaterial Database

Long-term changes in visual acuity and refractive error in amblyopes. 2004

Robert P Rutstein, and David A Corliss

School of Optometry, University of Alabama at Birmingham, 1716 University Boulevard, Birmingham, AL 35294-0010, USA. rrutstein@icare.opt.uab.edu

OBJECTIVE To report long-term changes in visual acuity and refractive error for strabismic, anisometropic, and isoametropic amblyopes. METHODS Records of patients with strabismic amblyopia, anisometropic amblyopia, and isoametropic amblyopia who were treated from 1983 to 1993 were reviewed. Excluded were patients having ocular or neurological diseases, developmental delay, and follow-up <4 years after treatment cessation. Data included best-correctable visual acuity and spherical equivalent refractive error of the amblyopic and the nonamblyopic eye at pretreatment, posttreatment, and long-term follow-up. RESULTS Records for 61 patients met the inclusion criteria. For strabismic amblyopia (n = 22), mean visual acuity in amblyopic and nonamblyopic eyes improved 0.36 and 0.05 logarithm of the minimum angle of resolution (logMAR) units after a mean treatment time of 1 year. At long-term follow-up (mean = 9.3 years after treatment), visual acuity in the amblyopic eye regressed 0.09 logMAR and visual acuity in the nonamblyopic eye improved 0.10 logMAR units. For anisometropic amblyopia (n = 26), mean visual acuity in amblyopic and nonamblyopic eyes improved 0.30 and 0.02 logMAR units, respectively, after a mean treatment period of 1.1 year. At the long-term follow-up visit (mean = 7.1 years after treatment), visual acuity in the amblyopic eye regressed 0.09 logMAR unit and in the nonamblyopic eye improved 0.03 logMAR unit. Repeated-measures analysis of variance showed no significant effect of type of amblyopia on visual acuity of the amblyopic eye and a significant effect of visit due to treatment but not regression. The changes in visual acuity in the nonamblyopic eye from the pretreatment to the follow-up visit were significant and interacted with type, the changes being larger in strabismic amblyopia. For strabismic amblyopia, the mean refractive error in amblyopic and nonamblyopic eyes changed from +2.15 D and +1.85 D, respectively, initially to +0.45 D and +0.58 D, respectively, at the follow-up visit. For anisometropic amblyopia, the mean refractive error in amblyopic and nonamblyopic eyes changed from +1.04 D and +0.12 D, respectively, initially to +0.23 D and -0.94 D, respectively, at the follow-up visit. The effect of visit on amblyopic and nonamblyopic refractive errors was significant. For isoametropic amblyopia (n = 13), visual acuity in both right and left eyes initially was 0.39 logMAR unit and improved to 0.14 logMAR unit in each eye after a mean follow-up of 8.9 years. Refractive error in the right and the left eyes changed from -1.22 D and -1.14 D, respectively, to -2.68 D and -2.56 D, respectively, at follow-up. These differences were all significant. CONCLUSIONS After treatment and with long-term follow up, visual acuity regresses but not significantly in the amblyopic eye in strabismic amblyopia and anisometropic amblyopia. At the same time, visual acuity in the nonamblyopic eye improves slightly. Visual acuity also improves significantly over time in isoametropic amblyopia. The refractive error of both amblyopic and nonamblyopic eyes tends to show a myopic shift regardless of the type of amblyopia.

UI	MeSH Term	Description	Entries
D012030	Refractive Errors	Deviations from the average or standard indices of refraction of the eye through its dioptric or refractive apparatus.	Ametropia,Refractive Disorders,Ametropias,Disorder, Refractive,Disorders, Refractive,Error, Refractive,Errors, Refractive,Refractive Disorder,Refractive Error
D002648	Child	A person 6 to 12 years of age. An individual 2 to 5 years old is CHILD, PRESCHOOL.	Children
D002675	Child, Preschool	A child between the ages of 2 and 5.	Children, Preschool,Preschool Child,Preschool Children
D005500	Follow-Up Studies	Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.	Followup Studies,Follow Up Studies,Follow-Up Study,Followup Study,Studies, Follow-Up,Studies, Followup,Study, Follow-Up,Study, Followup
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000293	Adolescent	A person 13 to 18 years of age.	Adolescence,Youth,Adolescents,Adolescents, Female,Adolescents, Male,Teenagers,Teens,Adolescent, Female,Adolescent, Male,Female Adolescent,Female Adolescents,Male Adolescent,Male Adolescents,Teen,Teenager,Youths
D000550	Amblyopia	A nonspecific term referring to impaired vision. Major subcategories include stimulus deprivation-induced amblyopia and toxic amblyopia. Stimulus deprivation-induced amblyopia is a developmental disorder of the visual cortex. A discrepancy between visual information received by the visual cortex from each eye results in abnormal cortical development. STRABISMUS and REFRACTIVE ERRORS may cause this condition. Toxic amblyopia is a disorder of the OPTIC NERVE which is associated with ALCOHOLISM, tobacco SMOKING, and other toxins and as an adverse effect of the use of some medications.	Anisometropic Amblyopia,Lazy Eye,Amblyopia, Developmental,Amblyopia, Stimulus Deprivation-Induced,Amblyopia, Suppression,Stimulus Deprivation-Induced Amblyopia,Amblyopia, Anisometropic,Amblyopia, Stimulus Deprivation Induced,Amblyopias,Amblyopias, Anisometropic,Amblyopias, Developmental,Amblyopias, Stimulus Deprivation-Induced,Amblyopias, Suppression,Anisometropic Amblyopias,Deprivation-Induced Amblyopia, Stimulus,Deprivation-Induced Amblyopias, Stimulus,Developmental Amblyopia,Developmental Amblyopias,Eye, Lazy,Eyes, Lazy,Lazy Eyes,Stimulus Deprivation Induced Amblyopia,Stimulus Deprivation-Induced Amblyopias,Suppression Amblyopia,Suppression Amblyopias
D013285	Strabismus	Misalignment of the visual axes of the eyes. In comitant strabismus the degree of ocular misalignment does not vary with the direction of gaze. In noncomitant strabismus the degree of misalignment varies depending on direction of gaze or which eye is fixating on the target. (Miller, Walsh & Hoyt's Clinical Neuro-Ophthalmology, 4th ed, p641)	Concomitant Strabismus,Dissociated Horizontal Deviation,Dissociated Vertical Deviation,Heterophoria,Heterotropias,Hypertropia,Non-Concomitant Strabismus,Nonconcomitant Strabismus,Phorias,Squint,Strabismus, Comitant,Strabismus, Noncomitant,Convergent Comitant Strabismus,Mechanical Strabismus,Comitant Strabismus,Comitant Strabismus, Convergent,Deviation, Dissociated Horizontal,Dissociated Horizontal Deviations,Dissociated Vertical Deviations,Heterophorias,Heterotropia,Horizontal Deviation, Dissociated,Hypertropias,Non Concomitant Strabismus,Noncomitant Strabismus,Phoria,Strabismus, Concomitant,Strabismus, Convergent Comitant,Strabismus, Mechanical,Strabismus, Non-Concomitant,Strabismus, Nonconcomitant
D014792	Visual Acuity	Clarity or sharpness of OCULAR VISION or the ability of the eye to see fine details. Visual acuity depends on the functions of RETINA, neuronal transmission, and the interpretative ability of the brain. Normal visual acuity is expressed as 20/20 indicating that one can see at 20 feet what should normally be seen at that distance. Visual acuity can also be influenced by brightness, color, and contrast.	Acuities, Visual,Acuity, Visual,Visual Acuities