Various ophthalmological diseases are now being routinely treated with intravitreal injection of pharmacological substances.
The vitreous is the jelly-like substance that fills the back part of the globe of the eye. Injecting substances directly into this jelly (intravitreal injection), allows delivery of high concentrations of the drug to the area where the greatest action of the drug is required, usually the retina. It is a potent form of treatment. It is generally considered a reasonably safe treatment. However, as with any surgical procedure, it is associated with some risks, but is generally considered a reasonably safe treatment. Your ophthalmologist will discuss with you the relative risks and benefits of such a treatment and also alternative treatment.
The eye is anaesthetised with local anaesthetic drops. The procedure is performed using an aseptic technique. The eye is cleaned with a strong antiseptic, which is essential to prevent an infection. The eyelids are then held open with a small speculum (clip) and the injection is performed using a very fine, disposable needle as shown in the figure. The procedure is usually performed in the rooms.
The white of your eye where the injection went in is likely to go red, which results from a bleed of the conjunctival vessel. It is harmless and may take 1-7 days to resolve. The eye may feel gritty once the effect of the anaesthetic wears off. These effects usually last a few hours and do not require any special treatment as they will wear off by 6-12 hours. You can take a mild analgesic tablet and/or lubricating drops if the eye is extremely uncomfortable.
Care must be taken not to rub the eye immediately after the procedure, since it can result in a corneal abrasion, which is extremely painful and can take upto 24 hours to heal. Often intravitreal injections do need to be repeated, especially when treating ongoing conditions. Your doctor will be able to inform you if this is the case and what a likely course of treatment may entail.