If you do a fluorescein angiogram for a patient immediately after a routine cataract surgery, you will likely find some degree of macular leakage. Even in a perfect surgery. Even in a younger and healthy patient. Just by doing the cataract surgery, we are inducing inflammation in the eye and the delicate macula can end up with some edema. For the majority of our patients, this macular leakage resolves within hours and by post-op day 1 the vision is remarkably clear. Sometimes, however, even though the vision is 20/20 initially, after a few more days or weeks, there can be accumulation of fluid in cystic spaces in the macula. This cystoid macular edema (CME) is a known risk of cataract surgery and fortunately, it resolves is nearly all cases. Initial treatment may be topical eye drops of steroids and NSAIDs, but occasionally intra-vitreal injections are needed. Keep in mind that there are certain risk factors for CME such as underlying vascular disease (diabetes / hypertension) and pre-existing epi-retinal membranes (ERMs). This video shows a case where a patient of mine, despite a beautiful and textbook perfect cataract surgery, developed CME. Fortunately, it resolved with treatment and the patient is back to 20/20.