1, intraocular injection Avastin can treat which diseases: Avastin belongs to a kind of anti-neovascular drugs, it can prevent the growth of new blood vessels, reduce the bleeding and exudation of abnormal blood vessels, reduce edema, so as to stabilize or improve visual acuity. At present, it is mainly used for: (1) macular edema caused by various reasons (including diabetic macular edema, macular edema after cataract surgery, macular edema caused by choroiditis or intraocular tumors, etc.) Qu Jinfeng, Department of Ophthalmology, Peking University People’s Hospital, Beijing, China (2) choroidal neovascularization due to various reasons (including age-related macular degeneration, high myopia, idiopathic choroidal neovascularization, angioid streaks, choroidal tumors or neovascularization secondary to inflammation, etc.). (2) Choroidal neovascularization due to various reasons (including age-related macular degeneration, high myopia, idiopathic choroidal neovascularization, angioid streaks, choroidal tumors or neovascularization secondary to inflammation, etc.) (3) Retinal neovascularization (e.g., diabetic retinopathy, retinopathy of prematurity, retinal vein occlusion, retinal vasculitis, Coats’ disease, etc.) (4) Neovascular glaucoma). Ranibizumab (Lucentis) is also an antineovascular drug with essentially the same mechanism of treatment as Avastin. The authoritative New England Journal of Medicine published the results of the CATT study in April 2011, which showed that the efficacy of Lucentis and Avastin in the treatment of age-related macular degeneration is comparable. In the United States, Lucentis has been officially marketed for the treatment of age-related macular degeneration since 2006, while Avastin, although widely used by ophthalmologists, has not been formally approved for the treatment of eye diseases. In China, Lucentis (Nosode) was officially launched in 2012, and the cost of each treatment is estimated to be around 11,000 RMB, while Avastin currently costs around 1,500 RMB per treatment. Since both drugs last in the eye for about 4-6 weeks, the treatment needs to be repeated every 4-6 weeks until the lesion is scarred. The huge difference in price between the two is the main reason why Avastin is now doubly popular. 3. What are the side effects and complications of intraocular injections? The biggest risk associated with intraocular injections is intraocular infection. Although the chances of this problem occurring are very low, once an infection occurs, it is more difficult to control with medication and surgery, and blindness is possible. Also injections are generally not recommended for pregnant women. Sometimes after opening the gauze on the second day of the injection, you may find flakes of bright red bleeding on the white part of the eye, which may be caused by the dilation of capillaries caused by the antiseptic solution prior to the injection and rupture during the injection, or it may be related to the patient’s high level of mental stress and elevated blood pressure at the time of the injection. This situation does not need special treatment, just need to observe for a few days, the bleeding will be self-absorbed, will not affect your vision recovery. 4. What do patients need to do before injection? First of all, you should let your doctor conduct a comprehensive examination and communicate with him/her fully to see if you have got the answers to the following questions: (1) What is your diagnosis? If it is age-related macular degeneration what type is it? If there is edema, what is the height of the edema? (2) Is intraocular injection treatment necessary? What is the likelihood that vision will improve with treatment? (3) What kind of medication is injected? What is the approximate cost of one treatment? Can it be reimbursed? There are a variety of drugs currently used for intraocular injections, such as Avastin (Avastin, Bevacizumab, Bevacizumab), Ranibizumab (Ranibizumab, Lucentis), VEGF-Trap, KH902, Triamcinolone acetonide (TA), and so on. (4) What are the possible complications of the injected drugs? (5) Is combined photodynamic (PDT) therapy required? (6) How do I make an appointment for the procedure? Secondly, you have to start using antibiotic eye drops 3 days before the injection. If you cannot use the eye drops 3 days in advance, you have to intensively dot the eye drops on the day of the surgery, for example, 1 time in 5 minutes, 5~10 times in total. The nurse will flush your tear ducts on the day of the injection. If you have conjunctivitis or inflammation of the tear ducts, the surgery may be delayed. It is a good idea to have someone accompany you on the day to help you with the registration, payment and signing procedures. It is generally not recommended to have both eyes injected at the same time. 5. What are the precautions for patients during the operation: When you enter the operating room, please keep quiet, too much talking may affect the medical staff to concentrate, and it is not conducive to keeping the air in the operating room clean. The nurse will first give you anesthetic eye drops several times, please remember the eye that needs to be treated and check with the nurse. Once you are lying on the operating table, please try to stay as relaxed as possible, do not tilt your head up or down too much, and keep your face parallel to the floor. When disinfecting the eyes, some patients who are sensitive to disinfectant may experience stinging in the eyes, which usually lasts for a short time and passes and is easily tolerated. Some of the disinfectant may run down the corners of your eyes. Please do not wipe them yourself as this may touch the disinfected area of your eyes and cause an eye infection. After sterilization, your face will be covered with a layer of sterile surgical sheet, you may feel a bit suffocated, then you can open your mouth to breathe, but do not pull the surgical sheet without authorization, to avoid eye infections. When injecting your eyes, follow the doctor’s instructions to look at the appropriate place, do not look around, so as to avoid accidental damage to your eyes caused by the needle. The procedure is very fast, plus the time for anesthesia is only a few minutes, patients basically do not feel uncomfortable. 6. What are the precautions for the patients after the operation: the following situations may occur after the operation, please do not be nervous: (1) small bubbles floating in the eye: this may be the small bubbles in the solution floating in the vitreous humor, usually the same day can disappear, and it will not affect your vision; (2) there is blood on the gauze: the disinfectant solution caused by the injection of the eye is congested, and the needle is easy to touch the capillaries to cause hemorrhage, although it looks red and scary, but in fact, it will not affect your eyesight. Although it looks red and scary, it actually has no effect on your vision and is usually absorbed in about 10 days. (3) After the operation, your eyes hurt a lot and there are a lot of tears in your eyes, like there is something in your eyes: it may be the stimulation effect of the antiseptic solution, if the pain is intolerable, you need to come to the hospital for a look; if it is still tolerable, it can be relieved on the next day. Don’t open the gauze on the day of surgery, you need to go to the hospital for checkup on the first day after surgery, and order antibiotic eye drops continuously for 1~2 weeks, at least 4 times a day, after that, when you need to have further checkup please consult your doctor. In general, you can return to normal life or work on the second day after surgery. However, you should pay attention to eye hygiene and avoid dirty water entering your eyes when you wash your face and take a shower. Reading books and watching TV will not directly affect the recovery of vision, but be careful not to get too tired. However, if there is obvious eye pain, obvious blurred vision, eye redness and congestion, etc., you should immediately go to the local hospital ophthalmology department, mainly to understand whether there is the occurrence of infection, must not be delayed! 7. How many times do I usually need to repeat the injection? How long is the interval? The number of injections varies from person to person and there is no fixed norm to follow. Generally the number of treatments for idiopathic choroidal neovascularization (mesothelium) will be less and may require 1-3 times. Macular edema in macular degeneration, venous obstruction, and diabetic retinopathy usually requires multiple treatments. Overseas, 1 injection per month is used, with more than 20 injections. Many of our patients have more than 10 injections, mainly based on OCT and fundus imaging results to see if there is still uncontrolled leakage. The time between each injection is mostly 4-6 weeks. If the lesion is stable, according to the monthly OCT and fundus imaging results, if the lesion is found to be enlarged or the leakage increases, then consider re-injection. 8. Which is better, intraocular injection of Avastin or photodynamic therapy (PDT)? Photodynamic therapy has been used for 7-8 years in China, it can make neovascularization closed and stabilize vision. Another great benefit is that there are basically no side effects or complications. The downside is that it is more expensive, around$17,000 to do it once. The great thing about intraocular injections of Avastin is that they are quite a bit cheaper and very effective, but the risks are much greater, the most dangerous being infection. Some doctors recommend “combination therapy”, that is, PDT combined with intraocular injection, which may be able to reduce the number of PDT or intraocular injections, reduce the cost, reduce the burden of the family’s multiple trips to the hospital, and most importantly, reduce the side effects and the risk of intraocular injections. 9. I have had several injections, how come my vision still hasn’t improved? The macula is the most important part of our human eye for vision. Once the macula gets sick, the effect on vision is very serious. Sometimes, because of the long period of time, the nerve cells have been irreversibly damaged, and although there is no more bleeding and edema, the scar left behind is right in the center of the macula, so the vision will not be as good as if you have not had the disease, and there may be distortion of vision, etc. Also, the current treatment is still treating the symptoms. Moreover, the current treatment is still treating the symptoms of the disease, and the medication can only last for a limited period of time in the eye, so there is still a possibility of recurrence. The degree of vision improvement is closely related to the location of the lesion, its size, the amount of bleeding, whether there is scarring, whether there is atrophy, whether the blood pressure and blood sugar are not well controlled, and so on, and it is difficult for doctors to accurately predict the degree of vision recovery.