Posterior Vitreous Detachment
What is the Vitreous? The vitreous is a clear jelly-like substance within the eye which takes up the space behind the lens and in front of the retina, the light sensitive layer at the back of the eye. What is Posterior Vitreous Detachment? Posterior Vitreous Detachment or PVD for short is a common condition which occurs in middle age. As people get older the vitreous, a jelly-like substance inside the eye changes.When a PVD starts the jelly comes away from the retina.As it comes away from the retina it can cause the symptoms of PVD. What are the Symptoms of PVD? Many people are not aware that they have developed PVD but others develop symptoms such as floaters or flashing lights. Floaters can take many forms from little dots, circles, lines, to clouds or cobwebs. The flashing lights occur as the outer part of the vitreous pulls on the retina as it comes away from it. This stimulation causes the sensation of flashing lights since the brain interprets all stimulation signals from the retina as light. Can anything be done to help with the PVD? No treatment is needed for PVD. The symptoms usually calm down overweeks and people get used to living with the floaters. The brain adapts to the floaters and eventually is able to ignore them, so they are only occasionally noticeable in specific conditions such as in very bright light. Will I lose any sight? Posterior vitreous detachment does not itself cause any loss of vision. Your visual acuity should remain the same that is you will be able to see just as you could before the posterior vitreous detachment started. You may have some difficulties to begin with because of the floaters and flashing lights. The only threat to vision is a small chance of a retinal tear leading to a retinal detachment. It is important to stress that retinal tears and detachments are much rarer conditions and that very few people with PVD go on to develop either of these problems Are retinal tears serious? Sometimes the as the jelly collapses it pulls quite strongly on the retina. Occasionally this may lead to the retina tearing which may lead to a loss of vision because of a retinal detachment. Warning signs of a retinal tear or detachment are An increase in size and number of your floaters A change/increase in the flashing lights you experience Blurring of vision A ‘curtain’ falling across your vision If you experience any of these symptoms you should contact us for advice urgently. Early intervention often allows treatment of a tear before it becomes a detachment and also increases the chances of a good recovery from a retinal detachment which may have already occurred. Will I need to keep seeing my Doctor? You will have had a thorough examination during your first visit with special attention to whether or not the retina is in any danger. If it isn’t then you may not need to see your ophthalmologist again. However if you begin to experience the symptoms warning of a possible retinal detachment, highlighted above, then you should seek urgent medical attention again. Dr Prasad will give you more specific advice when he sees you. Is there anything I can do to cope with these annoying symptoms? Floaters can be particularly annoying. They get in the way of seeing things and can make some things difficult, for example reading a book. There is a way of trying to cope with this that some people find useful. If you move your eyes around you can sometimes move the floater out of your direct field of vision. This works best if you have one large floater rather than lots of small ones. Making things bigger can also help while you have floaters so that you are able to see things ‘around’ the floaters. Most people find that with time the floaters become less and less of a problem. If you would like to read more about this condition, further information is available on the following websites: From the National Institute of health (NIH) USA: https://nei.nih.gov/health/floaters/floaters The American Academy of Ophthalmology: https://www.aao.org/eye-health/diseases/what-are-floaters-flashes
Retinal Detachment
This leaflet aims to give you some general information about the treatment and aftercare of this condition. The Retina The retina is the light sensitive layer at the back of the eye (film) which transmits the messages of the light rays along the optic nerve to the brain. Light rays enter the eye through the transparent (clear) cornea then pass through the pupil in the centre of the iris (coloured part of the eye) and onwards through the lens and vitreous (a jelly-like substance) before reaching the retina. Retinal Detachment If the retina separates from the underlying inner wall of the eye, a retinal detachment has occurred. This is similar to wallpaper peeling off a wall. The part that is detached (peeled off) will not work properly. The picture that the brain receives becomes patchy or may be lost completely. Nearly all retinal detachments develop because of a hole or tear in the retina. This usually occurs when the retina becomes ‘thin’ especially in short sighted people or if the vitreous separates from the retina. Other eye or health problems such as diabetes, after cataract operation and injury such as a blow to the eye can occasionally be the cause of a retinal detachment. Treatment Surgery is necessary to “reattach” the retina. Without surgery, vision will almost always be completely lost. Surgery is usually performed under local anaesthesia and occasionally under general anaesthesia. You will usually be admitted as “day case” and stay in hospital for for a few hours after the operation. There are two main kinds of operations used to reattach the retina. 1.Scleral-buckling: Pressure can be applied on the retinal detachment from the outside of the white of the eye. Fine bands made of silicone are stitched on to push in against the hole in the retina. These bands are left in place and usually do not cause any trouble. 2.Vitrectomy More usually an internal approach is used to re-attach the eretina from the inside by removing the vitreous and replacing it with a clear substance (air, gas or silicone oil) by using very fine instruments and an operating microscope. This closes off the break in the retina from the inside. Most procedures can be completed using microincision sutureless techniques. The eye is never removed and replaced when operations are carried out. If gas is used it will gradually be absorbed and disappear. The time this takes depends on the type and amount of gas inserted. It is replaced naturally by fluid from within the eye. If Silicone oil is used it remains in the eye until or unless a decision is made to remove it by another operation. The Other eye Having a retinal detachment in one eye means that you have an increased risk of getting a similar condition in the other eye. It is usual to examine the other eye in detail, so if any weak areas are found they can be preventively treated by laser or cryotherapy (freezing). This greatly reduces the risk of getting a retinal detachment in the other eye. This will usually not affect your vision, but the eye may be sore for a few days after treatment. Tests before surgery You may have tests (such as urine test, blood tests and an electrocardiograph ECG) to check you are in good health or if any special measures need to be taken to prepare you for your surgery and during and after surgery. After the operation Your operated eye will be covered with an eye pad and protective eye shield for the first night after operation. You may experience some discomfort immediately after the operation. If so, request medicine for pain/sickness relief. If you have had air, gas or oil inserted into the eye: Initially you should not lie on your back as the substance in your eye may float to the front of your eye and away from the retina. The nurse looking after you will advise you about movement as you may be asked to “posture”. This is positioning your head in a certain way if you have had bubbles of gas, air or silicone oil injected during the operation. For the first few days you must posture as directed day and night with only 10 minutes break each hour except for meals and hygiene purposes. When your eye pad is removed your eye may be red and swollen. The eye is then usually left uncovered to promote healing. You will have a pad or shield applied for protection at night and eyedrops will be prescribed. General Questions Will I be able to see properly again? If the operation to reattach your retina is successful, you will be able to see again but the quality of your vision may not be as good as previously. Gas or silicone fluid in the eye may mean the retina does not function fully immediately after operation and recovery of sight is usually a gradual process. What is the success rate of surgery In most cases, there is better than 80% chance of successfully reattaching the retina with one operation. But successful reattachment does not necessarily mean restored vision. The return of good vision after surgery depends on whether, and for how long, the macula (central part of the retina) was detached prior to surgery. If the macula was detached for a long duration, it is unlikely that vision returns to completely normalnormal. Still, if the retina is successfully reattached, vision usually improves. The best vision is usually not achieved for some weeks to months. What should I expect in the postoperative period? The eye will be red and slightly sore for a few days to a month. Severe pain is uncommon; if it occurs, inform the nurse or doctor immediately. The eye will water for several weeks, and you may find it more comfortable to wear a patch on the operated eye. Eye drops are required for a few weeks. These
Vitrectomy
A vitrectomy is an operation to remove the vitreous humor, a clear, transparent jelly from inside the eye. The vitreous humor is situated behind the iris, the coloured part of the eye and in front of the retina, at the back of the eye). It has no real function other than providing packaging inside the eye. Why is a vitrectomy done? The general indication for a vitrectomy are: Diabetic vitreous haemorrhage Retinal detachment Epiretinal membrane Macular hole Proliferative vitreoretinopathy Endophthalmitis Intraocular foreign body removal Retrieval of lens nucleus following complicated cataract surgery The Vitrectomy Procedure The vitrectomy procedure is usually done with a local anaesthetic however sometimes a full (general) anaesthetic may be needed in certain circumstances. The surgeon makes three tiny incisions in the eye for three separate instruments. These incisions are placed in the pars plana of the eye, which is located just behind the iris but in front of the retina. The instruments which pass through these incisions include a light pipe, an infusion port, and the vitrectomy cutting device. The light pipe is the equivalent of a microscopic high-intensity flashlight for use within the eye. The infusion port is required to replace fluid in the eye and maintain proper pressure within the eye. The vitrector, or cutting device, removes the vitreous gel in a gentle and controlled fashion. This prevents significant traction on the retina during the removal of the vitreous so no further damage to the retina is done. The procedure can take 1-2 hours depending on the reason for surgery. Once the jelly is removed the retina is repaired if necessary, any foreign bodies removed and, in the case of diabetics, any leaking blood vessels are sealed. Does the vitreous jelly get replaced? No, the jelly does not naturally replace itself. The eye maybe filled with various materials at the end of surgery: Gas bubble (this is absorbed in about 2 months). Transparent oil which is not absorbed and is surgically removed at a future date. Air (absorbed within a week). The eye produces its own clear fluid known as aqueous humor which, as the gas or air is absorbed, will gradually fill the vitreous chamber. Risks A vitrectomy is an extraordinary advance in the management of a variety of ocular conditions involving the retina and vitreous humor of the eye. The procedure has a good success rate and complications are relatively unusual. However, bleeding, infection, progression of cataract, and retinal detachment (about 1 in 20) are potential complications with this surgical procedure. Most patients who undergo a vitrectomy will need cataract surgery in the future, earlier than they otherwise would have. There is a very rare chance of developing an inflammation in the fellow eye (unoperated eye) after such a procedure, this is called sympathetic ophthalmitis. For the vast majority of patients who undergo a vitrectomy, there is a good prospect of some improvement in vision. The procedure is another marvel of modern medicine for patients with conditions that might otherwise be blinding, however the visual results are often limited by the underlying disease process. What to Expect After Your Vitrectomy Procedure Your rate of recovery will depend on many factors, however, the preoperative condition for which the vitrectomy was performed is the most important factor determining your rate of recovery as well as your final outcome. Your eye surgeon can advise you as to what to expect. Follow your surgeon’s advice carefully. In general, don’t expect your final visual outcome for a few weeks, at the very least. Patients are usually able to return to normal activity within a few weeks. Most of the healing occurs during the first month, but full visual recovery may take a few months. Expect your eye to be sensitive, swollen and red due to the nature of surgery. A scratchy feeling or occasional sharp pain is normal. Ice compresses gently placed on the swollen areas may help reduce the aching and soreness. Redness is common and gradually diminishes over time. You may notice a patch of blood on the outside of the eye. This is similar to bruising on the skin and slowly resolves on its own. If you have a deep ache or throbbing pain that does not respond to over-the-counter pain medication, please contact your surgeon urgently. You will be prescribed a combination of eye drops to instil on discharge home. These will help to prevent infection, reduce inflammation and rest the eye following your surgery. Drops to lower the pressure in the eye are also sometimes necessary. These will be required for several weeks. If gas or oil has been inserted into the eye, usually for retinal detachment surgery, you will be advised to position with your head tilted downwards. This helps to ensure that the gas or oil is lying against the area of retina which has detached encouraging it to heal in the correct place. You will be required to follow this instruction for at least 7-10 days, 50 minutes out of every hour during the day. At night whilst in bed, try to lie on your front as much as possible. You will have a follow up appointment in 1-2 weeks following surgery. Further appointments will be needed less frequently for a few months beyond. If a gas bubble is inserted at operation: When the eye is filled with gas, the vision is very poor. Patients can sometimes see better, though, while looking straight downward and holding an object just a couple of inches from the eye. As the gas bubble becomes smaller, the patient will see it shrinking towards the bottom of the field of vision. It may cause glare and double vision, especially when it is about halfway reabsorbed. When the bubble becomes rather small, it tends to break up into a few smaller bubbles before disappearing altogether. Certain precautions should be observed when there is a gas bubble in the eye. First of all, the patient must maintain the head position recommended by their doctor. In