Magnitude and Causes of Unilateral Absolute Blindness in a Region of Oman: A Hospital-Based Study

Abstract

Purpose.

To report the magnitude and causes of unilateral absolute blindness (no light perception) and barriers faced by persons with unilateral blindness in the South Batinah region of Oman.

Methods.

Between January and June 2002, 12,000 patients were evaluated for visual acuity, ocular pressure, anterior ocular biomicroscopic examination, and posterior segment indirect ophthalmoscopy examination by ophthalmologists at Al Rustaq hospital in Oman. Patients having no perception of light in at least one eye were included in the cohort. A closed-ended questionnaire was used to collect data on the personal profile, history of blindness, barriers perceived as the cause of blindness, and participants’ attitude towards eye care and quality of life following visual disability.

Results.

In the 12,000 patients studied, absolute unilateral blindness (no perception of light) was present in 122 persons, a rate of 1.0% in our series. The onset of blindness was gradual in 78 (63.9%) persons and 64 (54.9%) persons had unilateral blindness for more than 10 years. The main causes of blindness were phthisis/absent/disorganized blind eye, which was present in 64 (52.5%) persons; glaucoma, seen in 49 (40.2%) participants; and corneal opacity, seen in 8 (6.5%) persons. Eighty (14.8%) persons had <3/60 vision in the fellow eye. Thirty (24.6%) persons had cataract and 19 (15.6%) persons had glaucoma in the fellow eye. Forty-eight (39.3%) persons had undergone cataract surgeries while 2 (1.6%) persons were operated for glaucoma in the fellow eye. Lack of access to ophthalmic services and use of traditional medicines during the onset of blindness were reported by nearly half of the cohort. The attitude towards blindness was negative in two thirds of subjects.

Conclusions.

Cataract and glaucoma were important determinants of visual impairment in the fellow eyes of this cohort. These patients are at higher risk of developing bilateral impairment and need special care to prevent/treat visual disabilities in the fellow eyes. Using appropriate services, one can attempt attitudinal changes, rehabilitate them, and create a positive attitude towards life.