What is a Retinal Detachment?
A retinal detachment occurs when the retinal pigment layer of the retinaThe retina is the receptor of light at the back of the eye. It fulfils the same function as the film in a film camera or the image sensor in a digital camera. The retina translates the images into electrical signals that are sent via the optic nerve to the visual cortex in the brain, where it is interpreted as the images we see. See Info on Eyes – Anatomy. separates from the sensory layer thereof. This is frequently caused by vitreous (gel-like body inside the eye) traction on the inner aspect of the retina, leading to breaks or tears in the retina. Fluid then leaks through the break, and splits the retinal layer into two, causing the detachment. If a blood vessel is situated in the area of the break, there may be associated intra-ocular bleeding as well.
There are 3 types of retinal detachment:
- Rhegmatogenous: A break in the sensory retina causes fluid to dissect into the retina. This causes the pigment epithelial layerRetinal pigment epithelium - Retinal pigment epithelium (RPE) is the pigmented cell layer just outside the neurosensory part of the retina. This specialized tissue has numerous functions, including the nourishment and maintenance of the retinal visual cells. See Info on Eyes - Anatomy. to separate from the sensory retina and leads to a detachment (most common).
- Tractional: Scarring on the retinal surface or within the vitreous may effect tractional forces on the inner retina and lead to a retinal detachment without an associated break.
- Exudative: When fluid leaks from the choroid into the sub-retinal space in the absence of a tear or hole (seen with an inflammatory response in the eye), the retina will also detach.
- Light flashes.
- The sudden appearance of floaters.
- Visual field loss / curtain obstructing the vision.
- Wavy / distorted vision.
Causes / Risk Factors
- Lattice degeneration (peripheral thinning of the retina).
- High myopiamyopia is also known as nearsightedness. It results from an eye that is larger in size compared to a normal sized eye and/or a cornea that is relatively too steep, causing the image to focus in front of the retina instead of on the retina itself. See Info on Eyes, Optics and Refractive Errors - myopia. (nearsightedness).
- Family history.
- Posterior vitreous detachment.
- Diabetes mellitusDiabetes mellitus, or simply diabetes, is a group of metabolic diseases in which the ability to process glucose is impaired. If left untreated, diabetes can cause a host of long-term complications, including damage to the retina..
- The use of Pilocarpine eye drops.
- Uveitis (chronic inflammation of the eye).
- Previous retinal detachment.
- Blunt trauma.
- Penetrating injury.
It is important to treat a retinal detachment as soon as possible, to prevent the detachment from progressing, especially to the macular region, which is responsible for sharp, central vision. The longer the retina is deprived of blood supply and nutrition, the greater the chance that the retina loses its ability to function. The detached retina has to be reattached and kept in position. This can be done by the following modalities, or a combination thereof:
- Argon laser therapy.
- Cryopexy (freeze treatment).
- Scleral buckle around eye (pushes the wall of eye onto the break in the detached retina, thereby closing it).
- Vitrectomy (removal of vitreous body).
- Pneumatic retinopexy (gas injection that pushes retina against the back wall of the eye).
- Intra-ocular silicone oil tamponade (silicone oil pushes the detached retina against the back wall of the eye).