Low vision is a vision problem that makes it hard to do everyday activities.
Vision is the special sense by which the qualities of an object constituting its appearance are perceived through a process in which light rays entering the eye are transformed by the retina into electrical signals that are transmitted to the brain via the optic nerve.
Visual acuity of 6/18 down to and including 3/60 in the better eye’. A person with low vision is ‘someone who, after medical, surgical and/or optical intervention, has a corrected visual acuity in the better eye of <6/18 down to and including light perception or a central visual field of <20 degrees, but who uses or has the potential to use vision for the planning and/or execution of a task.’
Thus, Low vision is a reduced level of vision that cannot be fully corrected with conventional glasses.
TYPES OF LOW VISION:
- Central vision loss (not being able to see things in the center of your vision)
- Peripheral vision loss (not being able to see things out of the corners of your eyes)
- Night blindness (not being able to see in low light)
- Blurry or hazy vision
CAUSES OF LOW VISION:
- Age-related Macular Degeneration - Macula , the area on the retina responsible for sharp central vision, is affected causing diminished vision.
- Refractive Errors like High Myopia
- Strabismic Amblyopia
- Cataract - A cataract is clouding of lens in eye, thereby decreasing vision. Though treated surgically, few associated with ocular diseases may benefit with Low vision aids.
- Diabetic Retinopathy - In Diabetes, due to hypoxia ( less oxygen supply to retina ), there are vascular changes leading to haemorrhages (bleeding) and exudates ( leaks from vessel ). These changes in Macula may produce diminution of vision.
- Glaucoma– In Glaucoma, there is rise in intraocular pressure leading to damage to the optic nerve and diminution of vision.
- Retinal Detachment– Retina may separate from its underlying layer and leads to diminution of vision.
- Retinitis Pigmentosa - An inherited disease, usually affects peripheral vision to begin with, leads to night blindness.
- Retinopathy of Prematurity–Retinal vessels are not fully developed in premature infants. Premature infants are kept on oxygen in incubator. There is relative hypoxia in peripheral part of retina, which leads to new vessel formation and other complications, leading to diminution of vision.
- Optic Nerve Diseases like Optic Atrophy
- Heredomacular degeneration (Stargardt’s disease)
- Brain damage – There may be injury or disease of brain which may affect vision
- Difficulty recognising objects at distance.
- Difficulty in reading or close work.
- Difficulty in colour differentiation.
LOW VISION IN CHILDREN:
Low vision can change a child’s life. It not only affects their ability to see, but also their education and cognitive development. It can be caused conditions, such as:
- Amblyopia (or Lazy Eye)
- Birth trauma
- Brain injury
Few therapies which can help in this age are as followed:
- Vision Stimulation Therapy:
- Cognitive Visual Assessment:
- Counselling on Integrated Education:
- Early Intervention Program:
Low Vision in Adults
low vision develops in adults aged 18-50 years, it can be very devastating. It can be difficult for them to keep their jobs.
Common Causes of Low Vision in Adults:
- Retinal dystrophy
- Eye trauma
- Brain diseases or injury
Low Vision in the Elderly
- Macular degeneration
- Diabetic retinopathy
It is diagnosed by clinical examination,
Eye examination by snellens chart
Computer eye exam
Myopia- short sightedness is an error of refraction in which parallel rays of light from infinity come to focus in front of the retina, when accommodation is at rest.
Homeopathy is useful in initial stage it delays the progression of disease.
Homoeopathic remedies are effective for treating low vision not only treating but also for the prevention.Homoeopathic treatment prevent further progression of the disease.
PHYSOSTIGMA - Pysostigma is prescribed for nearsightedness which is progressing rapidly, accompanied by pain in the orbits. The person experiences photophobia along with blurred vision. Spasm of the ciliary muscle, irritability of the eyes and dim vision are present in Pysostigma.
RUTA GRAVEOLENS -Ruta is effective for myopia with severe headache. Heacahe occurs while reading, sewing and performing other near-sighted activities. Weakness of the ciliary muscles and blurred vision are also present.
AGARICUS MUSCARIUS-Agaricus is another effective medicine for Myopia. The person experiences difficulty in reading , as type seems to move or to swim. Double vision with flickering before the eyes.
VIOLA ODORATA- Viola Odorata is another medicine for Myopia, where it is accompanied by severe pain in the eyes. The person complains of severe pain in the eyes which radiates to the top of the head.
OLEUM ANIMALE-Oleum Animale is one of the effective Homeopathic medicines for myopia where the symptoms include blurred vision with smarting in the eyes. The person often sees glistening bodies before his eyes and complains of dim vision. Nearsightedness accompanied by twitching of the eyelids is another prescribing symptom
LILIUM TIGRINUM-Lilium tig is best for Myopia , there is myopic astigma. There is impaired vision , pain extending back . Hyperesthesia of the retina. Lilium tig is useful in restoring the power of weak ciliary muscles.
PHOSPHORUS-Phosphorus is another effective Homeopathic medicines for myopia. Fatigue of the eyes and head even when the eyes are not being overused is a key symptom for prescription of Phosphorus. It is prescribed for myopia with weak eyesight and an aversion to light.