Anti-VEGF therapy is a treatment of injecting an intravitreal drug directly into the vitreous body of the sick eye to avoid side effects of the drug on the body in case it is taken some other way (orally, by injection into the muscle, or intravenously). Due to the risk of an infection, the procedure is executed in controlled sterile conditions like eye surgery. This drug works for a certain time and as a rule, it must be injected again in specific time intervals to be fully effective. In case the disease stops developing, it is necessary to keep injecting a dose once or twice a year to keep the condition stable.
The intravitreal anti-VEGF injection can improve visual acuity. After the ophthalmological examination and necessary diagnostics, the doctor decides on the type of treatment, which depends on the localization of changes as well as the estimation of risk. AntiVEGF injections work directly on the vascular endothelial growth factor (VEGF), which stimulates the growth of unwanted blood vessels in the macula and bleeding. There is no use to give injections when the disease is in the phase of the scar, therefore we don’t recommend it.
Application
Anti-VEGF therapy is applied in the following conditions:
- age-related macular degeneration
- diabetes
- central retinal vein occlusion
Treatment of Age-related Macular Degeneration (AMD)
Currently, there is no drug for the dry age-related macular degeneration that can regain lost eyesight. However, the disease can be slowed down with a combination of antioxidants, Mediterranean diet, and regular physical activity.
The wet age-related macular degeneration is formed in the later stages of the disease and about 10% of people with macular degeneration have a significant loss of the central vision, mainly very suddenly, within a few days or weeks with characteristic image distortion. The loss of eyesight is caused by the increase of new abnormal blood vessels (choroid neovascularization’s) below the retina, which may bleed or cause macular edema. In case this type of macula degeneration isn’t treated, it may cause the loss of its function and scarring in the macula, which causes permanent loss of central vision.
The wet age-related macular degeneration can be treated with anti-VEGF therapy. The treatment aims to destroy as many blood vessels as possible and stop further bleeding and further visual impairment. Besides, the thermic effect of the laser treatment and photodynamic therapy (PDT) also slow down the progress of the disease, but less efficiently.
Treatment of Diabetic Retinopathy
It is well known that the VEGF levels are high in the vitreous body and the retina of the patient with diabetic retinopathy. VEGF increases the permeability of the blood vessel, effecting tight-junction proteins, which are an important factor in the cause of macular edema. In clinical practice, there are several drugs in the antiVEGF group, whose application and effectiveness in the treatment of macular edema is the topic of many scientific papers publicized in the last few years.
Maculopathy can appear together with neovascularization. If macula or neovascularization should be treated first depends on various factors, including the patient’s age and how severe retinopathy is. Generally speaking, with younger patients with active neovascularization, it is better to do pan-retinal photocoagulation, since the progression of neovascularization can be aggressive with these patients. The peripheral retina treatment can also decrease macular edema by reducing VEGF production. Doctors generally advise pan-retinal photocoagulation in several treatments to diminish the chance to worsen macular edema. With patients with less aggressive neovascularization, it is advisable to treat macula first and then do pan-retinal photocoagulation.
Treatment of Central Retinal Vein Occlusion
For treatment doctors use anti-VEGF therapy to decrease macular edema. This type of therapy is symptomatic because it doesn’t affect the cause of the disease but only affects the symptoms to decrease, i.e. the vision improvement.