Please enter verification code
Functional Amblyopia; A Blinding Disease in a Normal Eye
European Journal of Preventive Medicine
Volume 3, Issue 2-1, March 2015, Pages: 36-46
Received: Mar. 12, 2015; Accepted: Mar. 12, 2015; Published: Mar. 20, 2015
Views 3385      Downloads 176
Saman Wimalasundera, Department of Community Medicine, &In-Charge, Ophthalmologist, Community Ophthalmology Center, Faculty of Medicine, University of Ruhuna, Galle, Sri Lanka.
Article Tools
Follow on us
Amblyopia is reduction of vision with the proper optical correction either in one or both eyes.. The diagnosis of Amblyopia requires both the demonstration of visual acuity loss and the absence of an organic cause. A visual defect screening program was conducted on children aged 3-14 years of Bope-Poddala health unit area of the city of Galle Sri Lanka. Children aged 5-14 years were examined at each respective school. Children aged 3-5 years were examined at the pre schools .Children not attending to pre schools were examined in the community. All possitives and difficult to handle cases with a 10% of normal were referred to the ophthalmology clinic for secondary screening, investigation and diagnosis. Cases of diagnosed Amblyopia were called after one year for re-assessment. A total of 6685 school children and 934 preschool children were enrolled for this study. After exclusion, 5649 children were screened.Out of the total of 5649 children who were screened 439 (7.8%) were found to have eye diseases with or without visual defects giving a prevalence of 78/1000 children. Of those with such diseases, 88.8% had visual defects. The prevalence of visual defect was 6.9% (69/1000 children). Of the children with visual defects 90.0% (351) were due to refractive errors. The prevalence of refractive errors was 6.2% (62/1000 children).The analysis of the prevalence of different types of refractive errors showed that the prevalence of myopic astigmatism was 52.3%, Simple myopia was 24.6%, simple hypermetropia was 12.5%. Myopic astigmatism was the commonest type of refractive error in unilateral or bilateral involvement. The second commonest was simple myopia. It was found that out of 223 children with bilateral refractive errors 11.6% had unilateral Amblyopia and 17.5% had bilateral Amblyopia giving a total of 29.1%. Of all children with unilateral refractive errors 39.8% had Amblyopia. The development of Amblyopia among unilateral refractive errors was higher than bilateral refractive errors (p<0.05).The total prevalence of refractive Amblyopia was 2.1% of the population. Of them 1.4% had unilateral Amblyopia and 0.7% had bilateral Amblyopia. This difference was statistically significant. (P<0.05) Highest prevalence was observed in the age group of six and seven years (3.4% and 3.0%.). Distribution of Amblyopia among males and females were almost equal. The total prevalence of Amblyopia among children was 2.3%. Refractive Amblyopia calculated was 2.1% that consisted of 1.9% of Anisometropic Amblyopia.The strabismic Amblyopia was 0.2%. Deprivation Amblyopia was 0.2%. There were no Amblyopes found in the group of strabismic Amblyopia without refractive errors.
Refractive Errors, Amblyopia Simple Myopia, Myopic Astigmatism, Strabismus, Screening
To cite this article
Saman Wimalasundera, Functional Amblyopia; A Blinding Disease in a Normal Eye, European Journal of Preventive Medicine. Special Issue: New Frontiers of Public Health from the Pearl of Indian Ocean, Sri Lanka. Vol. 3, No. 2-1, 2015, pp. 36-46. doi: 10.11648/j.ejpm.s.2015030201.17
Steven, E., Rubin, M.D., Leonard, B. & Nelson, M.B. (August 1993)Amblyopia diagnosis and management Pediatric ophthalmology, Vo1. 40, No.4, 727:35.
Eugene, M., Helveston and Forest, D., (1984) Elvis pediatric ophthalmology practice- 2nd Edition, pg.77.
Tommila, V., Tarakkanen, A.,(1981) incidence of loss of vision in the healthy eye in amblyopia; British journal of ophthalmology, 65:575.
* Jampolsky, A., Flom, B.C., Weymonth, FW and moses, LE, (1955) unequal correct visual acuity related to anisometropia, Arch ophthalmol 59; 893-905.
* Philips CI; Strabismus anisometropia and amblyopia; Brit. J. of ophthalmol. (1969) 43: 449-60.
Von Noordeen GK.; Classification of amblyopia, American J. Ophthalmol (1967), 63:238-44.
Werner, D.B. and Scott, W.E. (1985) Amblyopia case reports, bilateral Ametropic – Hypermetropic amblyopia J. Paediophthalmol. And Strabismus 22:203-5.
Von Noorden, G.K. and Manmenee A.E. (1968) Clinical observations on stimulus deprivation amblyopia (Amblyopia ex anopsia) Am. J. Ophthalmol, 65:220-24.
Juler, F. (1971) Amblyopia from disuse; Visual acuity after traumatic cataract in children, Trans ophthalol. SOC: UK. 41:129-39.
Jastrzebski, G.B., Hoyt, C.S.andMarg, E. (1984) Stimulus deprivation amblyopia in children: Sensitivity, plasticity, and elasticity (SPE) Arch. Ophthalmol. 102:1030-4.
Doran, R.M.L. (1986) Assessment of vision in Amblyopia. Trans ophthalmol SOC. UK. 105.699-704.
Flom, M.C., Weymouth, F.W. and Kahneman, D. (1963) Visual resolution and contour interaction. J. optometric. SOC. America; 53:1026-32.
Atkinson, J., Pimm-Smith, E., Erans, C., Harding, G., and Braddick, O. (1986) Visual crowding in young children. Doc. Ophthal.Proc. 45: 201-3.
Hilton, A.F. and Stanley, J.C. (1972) Pitfalls in testing children’s vision by the cheridangardiner single optotype method. Br. J. ophthalmol 56: 135-9.
Bradley, A., Freeman, R.D. (1981) : Contrast sensitivity in anisometropic amblyopia. Incest ophthalmol Vis Sci, 21: 467-476.
Campbell, F.W.: (1983) Why do we measure contrast sensitivity? Behav Brain Res 10: 87-97,
Ingram RM, Walker C, Wilson JM, et al: (1986) Predictions of amblyopia and squint by means of refractions at age 1 year. Br J Ophthalmol 70: 12-15,
Atkinson, J. and braddck, O. (1979) Assessment of vision in infants: Applications to Amblyopia. Trans ophthalmol SOC UK 99: 338-343.
Atkinson, J. and Braddick O. (1983) Visual screening and photorefraction – The relation of refractive errors to strabismus and amblyopia. Behav Brain Res 10: 71-80.
Flynn, J. T. (1967) Spatial summation in amblyopia. Arch ophthalmol 78: 470-474.
Marilya, A. Moller, M.A. (December 1983) The visually handicapped child. Paediatric clinics of North America, Vol. 30, No. 6, 1185-1193.
Von Noorden, G.K., (1990) Examination of patients III, in bionocular vision ocular mortality. ed. 4 st. Louis, CV Mosby P 208.
16- Pediatric ophthalmology practice 2nd edition Eugene and Forrest. Pub: CV Mosby & Co. (1984) Toronto.
Science Publishing Group
1 Rockefeller Plaza,
10th and 11th Floors,
New York, NY 10020
Tel: (001)347-983-5186