Dr Lee Mun Wai
Welcome to the inaugural column on eye care from the perspective of Dr. Lee Mun Wai, Perak’s only fellowship-trained retinal surgeon. This column will serve as a forum for the discussion of eye diseases with an emphasis on the impact and treatment of diseases of the retina.
What is the Retina?
The retina is a light-sensitive tissue lining the back of the eye and is responsible for converting light rays into electrical impulses which are then transmitted to the brain for interpretation as images. If you think of the eye as a camera and the retina as the film of a camera, you will understand how a healthy intact retina is vital for normal vision.
Floaters in field of vision
What are floaters and what are their effects?
Floaters are specks, clouds or cobwebs moving in your field of vision and most often seen when looking at a plain background like a wall or the sky.
While floaters look as if they are moving outside the eye, they are actually tiny clumps of vitreous (gel-like substance) inside the eye. As we age, the vitreous thins and shrinks forming clumps and pulling away from the back wall of the eye; this is called a posterior vitreous detachment. Sometimes, as the vitreous pulls on the retina, one may experience flashes of light as well.
What causes a retinal detachment?
Partial loss of vision
In the vast majority of people with floaters, a posterior vitreous detachment is the cause and this is usually of no consequence. The floaters become less apparent with time and no treatment is usually necessary.
In some people, when the vitreous pulls on the retina, a tear can develop and this can eventually lead to a retinal detachment. This is the separation of the nerve layer of the retina from the wall of the eye. Somebody with a retinal detachment would also see floaters and flashes but in addition to that, there would be an initial partial loss of vision and if left untreated, this would progress to a total loss of vision.
Who is more likely to get retinal detachment?
People aged over 50 are at increased risk of developing a retinal detachment. Other risk factors include very short-sighted people (more than 600 degrees), people who have had previous eye injury or eye surgery and people with certain inherited conditions (such as Stickler’s or Marfan’s syndrome).
How is retinal detachment treated?
Surgery is the mainstay of treatment for retinal detachment. The procedure is usually performed by a retinal specialist – an ophthalmologist who has undergone advanced training in medical and surgical treatment of retinal disorders.
Generally, the sooner the retina is reattached, the better the chances that vision can be restored. There are several procedures which can be used to treat a retinal detachment – pneumatic retinopexy, scleral buckling and vitrectomy. More will be covered in future when Surgical Management of Retinal Diseases will be discussed.
Can you prevent a retinal detachment?
Unfortunately, with age being a significant risk factor, it is impossible to prevent or predict who is going to develop a retinal detachment. It is important however, to recognise the warning signs of floaters and flashes as potential harbingers of a serious visually threatening disease. This is particularly true for individuals who are at increased risk such as highly short-sighted people or those who are involved in contact sports. Early presentation to a retinal specialist could be vital to prevent further visual loss and hopefully restore vision.
Contact: Lee Eye Centre, Ipoh