CONDITIONS ASSOCIATED WITH LOW VISION

 

BY Mj Omeiza Ishaq 

Let it seem paradoxical, but visual impairment and the need for its rehabilitation are becoming more important because of the improvement in health care and general well-being delivery service. In reality of the world today, longevity is increasing. Optometrists, Ophthalmologist, low vision specialists and other healthcare practitioners are taking a higher strength in looking at the molecular and genetic factors associated with the causes of low vision. Basically, conditions mostly associated with low vision are age-related macular degeneration(ARMD), retinitis pigmentosa, glaucoma, in operative cataract, amblyopia, acquired traumatic brain injury, retinopathy of prematurity, retinal detachment, Albinism etc. 

In this article we will be discussing few conditions associated with low vision 

Age related Macular Degeneration

 ARMD is a degenerative condition that affects the retina, light sensitive part of the eye where images are focused. It occurs in two forms which are exudative(wet) and non-exudative(dry) age-related macular degeneration. Studies have not proven the exact causes of age-related macular degeneration but older age is considered a primary factor. Other contributing factors are cigarette smoking and nutrition imbalance. 

Retinitis Pigmentosa 

Retinitis Pigmentosa is the leading cause of inherited blindness, with an approximate of ¼,000 individuals experiencing the non-syndromic form of the disease within their lifetime. RP is a slowly progressive, bilateral degeneration of the retina and retinal pigment epithelium caused by various genetic mutations. The underlying mechanism involves the progressive loss of rod photoreceptor cells in the back of the eye.This is generally followed by loss of cone receptor cells. This pigmentation is seen in the fundus in the form of bony spicules. Retinitis Pigmentosa are mostly inherited conditions and an early presentable symptom is night vision loss. Diagnosis is made by examination of the retina finding dark pigment deposits with other supporting testing like visual field, electroretinogram or genetic testing. 

Cataract

Cataract is the opacity of the crystalline lens. This opacity stops light from entering the eye and reaching the retina thereby causing reduction in vision. In most cases, a surgical procedure is performed where the Crystalline lens is extracted and replaced with an intraocular lens. However, there are some conditions in which there are other associated diseases and this makes it unhealthy for extraction or removal. This causes reduction in vision and low vision therapy needs to be considered to improve the patient's functional ability.

Among others, all these conditions could result to low vision, if primary action taken through correction, management or treatment through optical, medical, and surgical intervention did not improve the vision.