Treatment of common causes of Visual Impairment
Glaucoma
Opticians routinely employ screening tests for glaucoma, and, if detected early enough, prompt treatment by medication (usually eye drops) stops the progression of the disease. If medication proves inadequate to control the progression of the disease, a trabeculectomy or similar drainage operation may be necessary, to reduce the chance of further damage. The damage caused by uncontrolled glaucoma is permanent and cannot be revised by medication or surgery.
In the Acute form of glaucoma, (caused by an anatomical narrowed space between the iris and cornea), a sudden build up of pressure leads to headache and visual symptoms such as halo-like blurring around lights at night. This requires urgent medication, and surgery to prevent serious and rapid visual loss.
An iridotomy, (a small window in the iris base unblocks the drainage area).
Cataract
Different parts of the lens may be affected by cataracts either the front, back, or middle. Treatment by surgical removal of the cataract, and replacement by either implanting a plastic lens into the eye, or special lenses (in spectacle or contact lens form) is usually very successful in restoring eyesight, though full eyesight may not be restored for some months.
The operation is most frequently done under local anaesthetic, with the patient awake. Cataract surgery is usually indicated when quality of life is affected, (e.g. difficulty in driving, working or reading).
Macular degeneration
At the moment, there is no treatment for the “dry” type of macular degeneration. There are some treatments available for the “wet” type age- related macular degeneration, though in most cases these stabilise the condition, rather than restore lost vision.
Diabetic retinopathy
Treatment can stabilise the condition but will not improve the existing level of vision. Prophylactic treatment by laser is needed if vision is threatened, and to cause regression of the new blood vessels, which may develop and to prevent the development of advanced retinopathy. Occasionally, bleeding into the vitreous (the jelly-like substance in the back part of the eyeball) may occur from an abnormal blood vessel. Surgery may then be needed. This is called vitrectomy.
Retinitis Pigmentosa
There is no treatment for this condition.
Retinal detachment
A detached retina is a medical emergency and is treated by early surgery for most full detachments. Small retinal tears or holes without actual retinal separation are treated by Argon laser, or sometimes by Cryotherapy (freezing.) This seals the hole or tear edges back into place. Larger retinal detachments tend to have a poorer prognosis, especially where the tear involves the macula.
Prompt treatment is strongly advised, and is rewarded by a better outcome. It may be months before optimum post-operative vision is fully apparent.
