Korean J Ophthalmol.  2012 Apr;26(2):80-83. 10.3341/kjo.2012.26.2.80.

Causes of Visual Impairment among Patients Referred to a Visual Rehabilitation Clinic in Iran

• Ramezani A
• Pardis M
• Rafati N
• Kazemi-Moghaddam M
• Katibeh M
• Rostami P
• Dehghan MH
• Javadi MA
• Rabbanikhah Z

• KMID: 1364859
• DOI: http://doi.org/10.3341/kjo.2012.26.2.80

Abstract

PURPOSE
Epidemiologic evaluation and investigating the causes of visual impairment in any society is a matter of concern and has a direct effect on the country's health care planning. In this study we describe causes of low vision and blindness in Iranian patients referred to rehabilitation clinics for taking vision aids.
METHODS
In this cross-sectional study, visual acuity was classified based on best-corrected visual acuity in the better eye according to the World Health Organization definition (blindness, visual acuity [VA] < 20 / 400; severe visual impairment, VA < 20 / 200-20 / 400; mild to moderate visual impairment, VA < 20 / 60-20 / 200). The causes of blindness and low vision were determined using the 10th version of International Classification of Diseases based on the main cause in both eyes. To describe data, we used mean +/- SD and frequency.
RESULTS
The study included 432 patients, 65% male, with a mean age of 43.6 +/- 25.5 years (range, 3 to 92 years). Mild to moderate visual impairment, severe visual impairment and blindness were present in 122 (28.8%), 196 (46.4%) and 105 (24.8%) of the patients, respectively. The main causes of visual impairment were retinal and choroidal diseases (74.5%), optic nerve and optic tract diseases (9.8%), vitreous and globe disorders (5.3%), congenital cataract (3.1%), and glaucoma (2.6%). The distribution pattern of the causes was similar in all age subgroups.
CONCLUSIONS
Diseases of the retina and choroid are the main cause of visual impairment among patients referred to an academic visual rehabilitation clinic in Iran.

Keyword

Low vision disorders; Rehabilitation; Vision; Visual aids

MeSH Terms

Adolescent
Adult
Aged
Aged, 80 and over
Audiovisual Aids
Blindness/*epidemiology/rehabilitation
Child
Child, Preschool
Choroid Diseases/*epidemiology/rehabilitation
Female
Humans
Iran/epidemiology
Male
Middle Aged
Optic Nerve Diseases/epidemiology/rehabilitation
Referral and Consultation/*statistics & numerical data
Rehabilitation Centers/*statistics & numerical data
Retinal Diseases/*epidemiology/rehabilitation
Vision, Low/*epidemiology/rehabilitation
Young Adult

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