Although our eyes are a very small organ, the arteries and veins of the retina are the only ones in the human body that can be seen with the naked eye through non-invasive tests – in other words, we can see the condition of the retinal arteries and veins simply through a fundus screening. For example, if a more typical large exudate is found in the fundus, it suggests possible diabetic nephropathy and requires a further visit to a nephrologist. If you see a fundus? Of course you have to go through the pupil. But since the human pupil is very small, an examination in such a small area may miss many tiny lesions. Therefore, I recommend that patients use a rapid dilating drug to quickly dilate the pupil to check the fundus. It only lasts six to eight hours, and there is no problem seeing far away after the pupil is dilated, so you can wear sunglasses in the sun. After the pupil is dilated, the doctor can diagnose and stage the eye based on the manifestations of the fundus, such as microangiomas, exudates, etc. “However, some patients do not cooperate with dilated eye examinations because they are too troublesome to do so, but I would like to emphasize that dilated eye examinations are essential for the diagnosis and treatment of eye diseases.