A Comparison of the Causes of Eligible Legal Blindness in a Tertiary Government Hospital among Working Age Adults (15-64 years old) in 2008 and 2014

Objective:

To evaluate the visual and refractive outcomes of LASIK, PRK, phakic IOL, and Supracor as treatment for errors of refraction, including presbyopia, performed at a private eye center.

Methods:

Data were collected from the DOH Eye Center records section. The charts of new patients seen at the general ophthalmology clinic in the years 2008 and 2014 were reviewed individually. Patients between 15 and 64 years old with best-corrected visual acuity (BCVA) of 20/200 (6/60) or less in the better-seeing eye were included as subjects in the study. Patients who improved to better than 20/200 (6/60) with BCVA and any medical or surgical means were excluded from the study. Patients whose visual acuity could not be assessed for any reason or with reversible causes of blindness were also excluded from the study

Results:

The DOH Eye Center general ophthalmology clinic had a total of 8,941 registered patients aged 15 to 64 years old during the period January 1 to December 31, 2014. Diabetic retinopathy/maculopathy together with pathologic myopia formed the largest category of irreversible legal blindness (BCVA of 20/200 or less on the better seeing eye) with a total of 26 (18%) patients for each. Retinitis pigmentosa and macular dystrophy under the hereditary retinal disorders formed the second largest cause of legal blindness with 17 (12%) followed by glaucomatous optic neuropathy from all kinds with 15 (10%). Together, these four entities comprised more than 58% of all causes of blindness in the working age group. Optic atrophy, comprised mostly of ethambutol toxic optic neuropathies (ETON), was responsible for 14 (10%) followed by congenital disorders and corneal disorders of the eye with 7 (5%) for each. Other conditions comprised of disorders of the neural cortex; this formed 6 (4%) eligible causes of legal blindness. Uveitic causes and retinal detachment also contributed 6 (4%) each to the pool of eligible cases of legal blindness. Other conditions were endophthalmitis, central retinal artery occlusion and clinically significant macular edema which collectively contributed 6% to the pool. In comparison, the main causes of eligible legal blindness in the DOH Eye Center in 2008 were glaucoma, which accounted for 21% and was the single leading cause of blindness, followed by diabetic retinopathy (16%), retinal detachment 11%), pathologic myopia and optic atrophy (10%).

Conclusion:

The leading causes of legal blindness in 2014 were shared between diabetic retinopathy/maculopathy and pathologic myopia. In 2008, the single leading cause of legal blindness was glaucoma from all kinds, but after 6 years, it was overtaken by diabetic retinopathy and maculopathy. The decrease in blindness caused by glaucoma may be related to increased promotion of awareness of blindness due to glaucoma.

Keywords: legal blindness, severe visual impairment, visual disability, disability claim, irreversible blindness