UMMC study: Early detection key to prevention of blindness

A study in University of Malaya Medical Centre (UMMC) underscored the need for early detection of visual impairment in preventing blindness in every age group. The study also highlighted visual impairment is mainly caused by cataract, glaucoma and diabetic retinopathy in older persons and untreated refractive error in children.

The study published in the Malaysian Family Physician Journal sought to find out the prevalence of visual impairment and eye diseases as well as the various investigations conducted in UMMC’s ophthalmic outpatient clinic. [2024;19:30] Researchers reviewed the electronic medical records of 1002 patients who attended the clinic. About 60 percent of patients had no visual impairment, 12.3 percent had mild visual impairment, 20.4 percent had moderate-to-severe visual impairment, and 0.9 percent were found to be blind. The remaining 5.5 percent of patients could not be evaluated due to their exceedingly young age or markedly cognitive and physical disabilities.

Regarding the presenting symptoms, 541 were follow-up patients thus they had no active or serious symptoms. Among the rest, blurred vision (219), red eyes (35), floaters (30), swollen eyelids (25), and dry eyes (22) were commonly seen. Other symptoms included headache, foreign body sensation, sticky eyes, glaring, diplopia, squinting, and gritty eyes.

Notably, a sizeable number of the patients were found to have cataract (213), glaucoma and other lens-related diseases (123), and diabetic retinopathy including maculopathy (84) and other retinal diseases. Four patients had severe visual impairment due to cataract while three patients became blind due to glaucoma. Out of the 219 patients with blurred vision, 79 had cataract. Also, 112 of the 541 patients with no eye-related symptoms had cataract.

Overall, 419 investigations were conducted throughout the study duration of 3 weeks. The slit lamp examination and visual acuity test were the only investigations conducted on more than 53 percent of the patients. For the rest, optical coherence tomography (OCT), Humphrey visual field testing and refraction testing were the additional investigations. OCT was in high demand since it helps with early diagnosis of retinal diseases and glaucoma by observing variations in the retinal nerve. Other less common investigations included Hess chart, fundus photography, B-scan ultrasonography, fundus fluorescein angiography, specular microscopy, and corneal topography.

In comparison, a similar study conducted in UMMC in 2008 showed the prevalence of moderate-to-severe visual impairment and blindness was 9.8 percent and 0.9 percent, respectively. The increased prevalence of moderate-to-severe visual impairment is likely due to UMMC being one of the biggest tertiary centers in Malaysia where more patients with moderate-to-severe visual impairment are referred to. Rapid urbanization in Kuala Lumpur also contribute to the increasing number of patients, which in turn, causes rising burden of age-related eye diseases.