kind of cyst it is and if it is presumably a solid tumor. FNA is used as a last diagnosis method because it is the most invasive method since the eye has to be penetrated with a needle. FNA has been very successful with differentiating tumors with cystic spaces, like melanomas, adenomas or metastatic tumors. FNA can also be used as a treatment. Other ancillary procedures MRI is not used as a diagnosis method by itself. It is more used as a method to gain some extra information about the cyst. Magnetic resonance imaging can establish very well whether the cyst is in contact or attached to the sclera or whether the cyst is a primary tumor. Treatment options Observation The preferred treatment option is observation, since most iris cysts do not hurt or cause any pressure. A veterinarian however prefers to check the cyst from time to time to make sure that the cyst does not grow and does not cause any problems or pain. If the cyst is growing, causing pain or some issues over time, then the cyst will need another treatment. Fine-needle aspiration Fine-needle aspiration (FNA) is, as discussed earlier, also a diagnosis method but can also be used as a treatment. With FNA a very fine needle is inserted in the eye in the cyst. The purpose of the needle is to penetrate the membrane of the cyst, so that the cyst will deflate. This method has proven to be successful but there is a possibility that the cyst will not disappear fully but only shrink. If the cyst has shrunk enough that it is not causing any pain or trouble anymore, then a second treatment might not be necessary. But if the cyst is still causing an issue after the treatment, the treatment must be repeated, or another method has to be used. Intracystic injection of absolute alcohol Intracystic injection of absolute alcohol has proven to be a very effective method. The alcohol gets injected in the cyst through a needle which is penetrating the eye from outside into the cyst. The injection of the alcohol regresses the cyst or will at least stabilize it. It can take a few weeks before the cyst has disappeared fully. A common side effect of this method is an inflammation in the anterior chamber, but this can easily be treated with topical steroids (cream or gel with