Retinal Detachment
In order to function properly, the retina needs to be flat against the back of the eye. When a retinal detachment occurs, the retina is unable to stay in its normal position. The retina does not work when it is detached. If retinal detachment is not treated quickly, it may lead to permanent blindness.
Symptoms of Retinal Detachment
Some of the early symptoms that may indicate a retinal detachment are:
- Flashing lights
- New Floaters
- Blurry vision
- New area of shadow or curtain in the periphery of the vision
- Gray shadow in your vision
Presence of any or all of these symptoms does not always indicate a retinal detachment. These symptoms may also be seen in association with certain other conditions. Only a trained ophthalmologist can tell whether a retinal detachment is present or not. Thus you should see your ophthalmologist as soon as possible.
The causes a Retinal Detachment
As we get older, the vitreous liquefies and can separate from the back of the eye in a condition called Posterior Vitreous Detachment or PVD. This separation usually happens cleanly without any problems. However if the vitreous is densely adherent at any point, as it separates, it can cause the formation of a retinal tear. Then the liquid vitreous can travel through the tear to area behind the retina and thus peels the retina off the back of the eye, much like wallpaper peeling off the wall.
Certain conditions can predispose people to developing retinal detachments:
- Nearsightedness
- History of cataract surgery
- Trauma
- History of retinal detachment in other eye
- Family history of retinal detachment
- Certain weak areas in the retina
- Presence of certain systemic conditions like Marfan’s Syndrome
- Diagnosis of Retinal detachment
In order to definitely diagnose a retinal detachment, you need to undergo a dilated exam by your ophthalmologist
Treatments of retinal detachment treated depending upon the location and extent of retinal detachment, your doctor may choose one of several options available to treat the retinal detachment.
1. Scleral Buckle
This surgery places a silicone band around the eye to bring the detached retina and the eye wall closer together to relieve the traction of vitreous on the tear. This reduces the amount of fluid getting through the hole. In addition, the surgeon may use a freezing probe or laser to help close the tear. If the band goes around the eye completely, it is called an encircling band. Sometimes only a small area may need a band. This procedure is usually done under local anesthesia in the operating room. However general anesthesia is also sometimes used. This band stays around the eye permanently.
2. Pneumatic Retinopexy
If the location of the tear and accompanying detachment is located in the upper part of the eye, then the doctor might elect to inject some gas into the eye in the office. Then the patient is asked to position the head in certain way to aid in drainage of fluid underneath the retina. A few days after this, the doctor will place some laser around the tear to help keep it from causing the detachment again.
3. Vitrectomy
Occasionally, a retinal detachment is so complicated and severe that it cannot be treated with either standard scleral buckling surgery or pneumatic retinopexy. In such cases, vitreous surgery to reattach the retina may be necessary. Vitreous surgery is performed in an operating room usually under local anesthesia. The vitreous is removed and, therefore, this procedure is called vitrectomy. The surgeon uses a fiber optic light to illuminate the inside of the eye and other instruments inside the eye, such as forceps, and scissors, to do the surgery. The vitreous is replaced during the operation with either clear fluid that is compatible with the eye, or with gas that completely fills the eye. Over time, the fluid (or gas) is absorbed by the eye and replaced by the eye’s own fluid; the eye does not replace the vitreous itself. The lack of vitreous does not affect the functioning of the eye.
Vitrectomy is required for retinal reattachment in a variety of conditions. For example, scar tissue may grow on the vitreous or the surface of the retina and pull on the retina and detach it. Occasionally, something in the vitreous, such as blood, prevents the passage of light through the eye to the retina. The most common conditions requiring vitrectomy are vitreous hemorrhage with retinal detachment, proliferative vitreoretinopathy, giant retinal tears, diabetic retinopathy with vitreous hemorrhage and/o traction retinal detachment, epiretinal membrane(macular pucker), intraocular infection:endophthalmitis, trauma, intraocular foreign body, and macular hole. Today vitrectomy is often used to repair retinal detachment in eyes that have already cataract surgery.
In a vitrectomy, instruments are passed through the sclera into the vitreous cavity. A variety of instruments can be used to remove the vitreous gel and any scar tissue that may be growing on the surface of the retina. A laser probe can be inserted into the eye so that laser treatment can be done during surgery. Recent advancements in technology have led to smaller instrumentation for vitrectomy surgery. Standard size for vitrectomy was 20 gauge until recently when much smaller 23 or 25 gauge instrumentation became available. No suturing is required in most cases. Healing is quicker, pain is less, and the overall experience of vitrectomy surgery is much more comfortable for the patient.
Vitrectomy can be combined with the placement of a scleral buckle. Usually, air, gas, or silicone oil is place in the vitreous cavity. These materials hold the retina in place against the back wall of the eye while the laser scars are forming. After this surgery, it may be important for the patient to maintain a certain position of the head, which is often a face-down (prone) position. Eventually, the gas is absorbed and replaced by fluid produced by the eye. If silicone oil has been used, it frequently must be removed at a later time with another surgical procedure. Vitreous surgery usually lasts one to two hours but, with very severe and difficult problems, may take longer. Following surgery, the patient may experience some discomfort and a scratchy sensation in the eye, but significant pain is unusual. If it occurs, the surgeon should be told promptly
About the Retina
Retina is a layer of nerve tissue that senses the light coming into the eye and communicates this information to the brain.The front part of the eye consisting of cornea and the lens focuses light onto the retina. Acting like a film in a camera, the retina captures the light and transmits it to brain where the light is processed into recognizable images
Vitreous
Vitreous is a gelatin like substance that fills the eye between the lens and the retina. It is densely adherent to a circular area adjacent to the lens called vitreous base. It is very lightly adhered to retinal blood vessels and to area around the macula on retina and the optic nerve head. Vitreous is like solid Jell-O at the time of birth and slowly degenerates with age becoming more liquid. Vitreous acts as a reservoir for certain nutrients and oxygen for retina but a definite role is not known at this time. As this transformation happens, the vitreous can separate from the back of the eye in a condition called Posterior Vitreous Detachment or PVD. This usually presents as flashing lights or floaters. This can be accompanied by formation of retinal tears or development of retinal detachment. Thus it is very important for anyone developing symptoms of flashing lights or floaters get a comprehensive eye exam by an eye specialist.
Macula
Macula is central part of the retina that affords us the finest vision. The center of this area called the fovea is the area that allows us 20/20 vision.