Intra-vitreal injections for Wet Macular Degeneration
This video shows the techniques involved in treating wet macular degeneration with intra-vitreal injections of anti-VEGF drugs such as Avastin, Lucentis and Eyelea. These drugs inhibit the chemicals that cause aberrant blood vessels to grow into the macula part of the retina from the layer underneath called the choroid.
Untreated these vessels can haemorrhage and leak fluid into the retinal structures, causing distortion of the photo-receptor layer so that the vision is compromised. If this retinal disturbance is allowed to remain for more than a few weeks the poor vision can become permanent, so it is important that the condition is caught early and treatment started promptly, ideally within a week or two after onset. Regular OCT scanning of vunerable age groups and regular use of the amsler chart can make early diagnosis possible.
These drugs are given by injection into the Vitreous or jelly within the back portion of the eye. This video will show how this is done. Although this may look a bit frightening to the timid or apprehensive patient, the eye is heavily numbed prior to the injection using 2 different types of anaesthetic drops. We use proxymetacaine and tetracaine, although sometimes lignocaine is given either topically or by sub-conjunctival injection.
Next disinfectant 5% iodine drops are instilled into the eye to kill any germs within the tear film.Then the lids and lashes are cleaned with 10% iodine solution.
Sometimes a drape is used, though this is less common nowadays. Some people find the drape makes them feel a little claustrophobic. A lid clamp is then applied to keep the eyes open during the procedure
Further anaesthetic is applied to injection site with a sterile cotton applicator, prior to the injection site is marked with a measuring device. This is normally 3.5 mm from the edge of the limbus.
The patient is then reassured and told to keep eyes still and the drug is gently injected, the needle is withdrawn and a cotton applicator held against the injection site as a tamponade
Artificial tears are instilled and antibiotics as required
Further information can be found at http://www.matheson-optometrists.com