Anomalies of Refraction, Accommodation and Binocular Single Vision in Down syndrome

Saima Ahmad, Imran Ahmad, Asad Aslam Khan

Abstract


Purpose: Down syndrome is one of the common chromosomal abnormalities. Many ophthalmic features are studied and reported previously. The aim of this study is to investigate and thoroughly study the anomalies of refraction, accommodation and binocular single vision in Down syndrome along with strabismus and ocular abnormalities.

Material and Methods: Total of 40 children with Down syndrome, age ranging from 6 years to 14 years old underwent ocular assessment including visual acuity assessment, non-cycloplegic refraction, ophthalmoscopy, ocular alignment and ocular motility tests and tests for binocular single vision

Results: Among the population of 40 children with Down syndrome. 40% children had hypermetropia, 37.5% had Astigmatism and 5% had myopia. Esotropia was the most common deviation with 60% involvement. The binocular single vision was found to be affected as well. It was completely absent in 12.5% of the population whereas 25% population had only grade I and 17.5% had grade II BSV. Other ocular findings were also noted and their respective prevalence was Nystagmus 15%, Cataract 25%, Blepharitis 10%, conjunctivitis 12.5%, iris abnormalities 10% and keratoconus 5%

Conclusion: Main anomalies of refraction were found to be hyperopia and astigmatism. Near point of accommodation was reduced as was the reduced amplitude of accommodation. Binocular single vision is also found to be disturbed in the presence of strabismus. Other ocular abnormalities like cataract, nystagmus and blepharitis are also encountered. Further studies are required to identify association with other anomalies which can be related to vision and must be diagnosed and treated with best treatment regime available.


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References


Al-Shawaf R, Al-Faleh W. Craniofacial characteristics in Saudi Down's syndrome. King Saud Univ J Dent Sci. 2011;2:17-22.

Hecht CA, Hook EB. The imprecision in rate of Down’s syndrome by I-year maternal age intervals: A critical analysis of rates used in biochemical screening. Prenat Diagn.1994; 14:729-38.

Percy M, Schormans AF. Editorial: Journal on Developmental disabilities. Vol.12, No.1.

Rehman S, Obaid-ur-Rehman M. “Prevalence rate of Down syndrome in Karachi resident women”. Pak J Pharm Sci. 2005 Apr; 18(2):61-3.

National Institutes of Health. (2008). Facts about Down syndrome. Retrieved on October17,2008,fromURL: http://www.nichd.nih.gov/publications/pubs/downsyndrome.com.

Malini SS, Ramchandra NB. Possible risk factors for Down syndrome and sex chromosomal aneuploidy in Mysore, South India. Indian J Hum Genet. 2007 Sep-Dec; 13(3):102-108.

US national Library of Medicine. Down Syndrome. Cited on September 17th, 2015. From URL: http://www.nlm.nih.gov/medlineplus/ency/articles/000997.htm.

Baum RA, Nash PL, Jessica EA, Foster JE, Spader M. Primary care of children and adolescents with Down syndrome. Curr Probl Pedriatr Adolesc Health Care. 2008;38:241-261.

Izquierdo NJ, Townsend W. Ophthalmologic Manifestations of Down syndrome. Mescape. Cited on September 17th, 2015. From URL: http://emedicine.medscape.com/article/1200824-overview.

Ebeigbe JA, Akpalaba R. Ocular health status of subjects with Down's syndrome in Benin City, Nigeria. Afr J Med Sci. 2006;35:365-368.

Krinsky-McHale SJ, Jenkins EC, Zigman WB, Silverman W. Ophthalmic disorders in adults with Down syndrome. Current Gerontology and Geriatrics Research. 2012;1(3):7.

Han DH, Kim KH, Paik Hj. Refractive errors and strabismus in Down syndrome in Korea. Korean J OPhthalmol. 2012 Dec;26(6).

Morton GV. Why do children with Down syndrome have subnormal vision? Am Orthopt J. 2011;61:60-70.

Tsiaras WG, Pueschel S, Keller C, Curran R. Giesswein S. Amblyopia and visual acuity in children with Down’s syndrome. Br J Ophthalmol. 1999;83:1112-1114.

Elkington AR, Frank HJ, Greaney MJ. Clinical Optics. Ch No.11. Presbyopia. 3rd Edition. P141-143.

Haugen OH, Høvding G, Eide GE. Biometric measurements of the eyes in teenagers and young adultswith Down syndrome. Acta Ophthalmol Scand 2001;79: 616–625.

Yurdakul NS, Ugurlu S, Maden A. Strabismus in Down syndrome. J Pediatr Ophthalmol Strabismus. 2006;43:27-30.

Catalano RA. Down syndrome. Survey of Ophthalmology. 1990;34(5):385-389