Eyes as a human organ, seemingly simple structure. But Xue Baochai is “eyes like water apricot”, Lin Daiyu is “like happy non-happy with love eyes”, while the Phoenix spice but long “a pair of single phoenix triangle eyes”. The key to why there are so many different kinds of bright eyes is the eyelid, which is often overlooked. The eyelid, commonly known as the eyelid, is located in front of the eye and is one of the most important barriers that protects the eye, and also plays a role in maintaining the beauty of the eye and even the face. The eyelid skin is the thinnest and most delicate skin in the body, and many pathologies can cause swelling of the eyelid. However, most patients with eyelid swelling have few symptoms that they can notice, such as pain and discomfort, in addition to their swollen eyelids affecting their appearance, so it is often overlooked or sometimes slowly accepted by the patients themselves that eyelid swelling has little impact on their health, so they take it for granted that it is not important and do not pay attention to it. In addition, some patients with swollen eyelids tend not to come to the doctor because they are afraid to seek medical help. I once met a patient who had swollen eyelids for 5 months without any eye discomfort, but later came to our hospital with significantly increased eyelid swelling. However, if the patient had continued to delay treatment, the consequences would have been unimaginable. This shows that this more common symptom, eyelid swelling, can sometimes have serious health consequences and even lead to irreversible outcomes due to delayed treatment. Why are eyelids more prone to edema and swelling than other parts of our body? It starts with the anatomy of the eyelid. Generally speaking, the eyelid can be divided into five layers, from front to back: skin, subcutaneous tissue, muscle layer, lid plate, and conjunctiva. The eyelid is divided into the upper and lower lids, and the fissure between the upper and lower lids is called the lid fissure. The medial and lateral ends of the lid fissure are called the medial and lateral canthus, respectively, and are commonly referred to as the inner and outer corners of the eye. Both the upper and lower eyelids have an anterior and posterior surface. The anterior side is the skin and the posterior side is the conjunctiva. Between the two are the subcutaneous tissue, the muscularis and the lid. The thin skin layer of the eyelid and the loose connective tissue under the skin make it easy for the eyelid to become swollen due to water retention. II. Causes of eyelid swelling Causes of eyelid swelling include systemic factors, such as abnormal thyroid function, kidney disease, and heart disease; local factors, microbial infections, mosquito bites, allergies, trauma, angioneurotic edema, eyelid skin laxity, lacrimal gland prolapse, and more serious eye swelling. In other patients, although no obvious cause has been identified with our current instrumentation, this eyelid swelling is generally classified as idiopathic eyelid swelling, but at this point it cannot be considered normal and is only considered to be a mild degree of eyelid pathology that can be observed without special disposition, but it does not mean that there is no pathology at all. In recent years, studies have been conducted on eyelid swelling, and it is believed that the eyelid itself, as well as the tissues and structures surrounding the eyelid, can cause swelling of the eyelid. In particular, some diseases that originate from the orbital contents can cause swelling of the eyelid, and sometimes can cause painless, asymptomatic swelling of the eyelid, which can be particularly confusing and harmful to the patient. For example, in recent years, our group, with funding from the National Natural Science Foundation of China, has studied benign lymphoepithelial lesions, which were previously thought to manifest primarily as lesions of the lacrimal and salivary glands bilaterally and to increase in size, but we have found through our research that painless swelling of the eyes with no obvious cause is the most predominant symptom of the disease, and that this eyelid swelling is caused by the diseased lacrimal gland. Studies have shown that a certain percentage of patients with this disease may develop malignant changes. If a patient with this disease is seen and we only focus on the swelling of the eyelid, knowing only what it is and not what it is, this may lead to misdiagnosis and omission, causing unnecessary damage to the patient. III. Examination of eyelid swelling In patients with eyelid swelling, we should not only focus on the swelling of the eyelid due to local factors, but also consider the possibility of systemic diseases causing eyelid swelling. To this end, we can generally determine whether the eyelid swelling is of cardiac origin by doing the necessary measures such as electrocardiogram and cardiac ultrasound; we can rule out whether the eyelid swelling is of nephrogenic origin by checking the urinary routine and kidney function; and we can know whether the eyelid swelling is due to abnormal thyroid function by examining the thyroid gland and its function. However, based on our observations, the causes of eyelid swelling are still commonly localized to the eye. By touching the eyelid, we can sense the degree of eyelid swelling and whether it may be caused by a tumor of the eyelid itself. Because intraorbital lesions can cause eyelid swelling, and most intraorbital lesions cannot be felt by touching the eyelid alone, they need to be examined using ocular medical imaging methods, which commonly include ultrasound, CT, and MRI. cause. In most cases where an intraorbital lesion is the causative agent for the eyelid swelling, surgery may be required to remove the diseased tissue and perform pathologic histology to make a definitive diagnosis. When it comes to surgical biopsy, some patients often refuse to undergo it due to a lack of awareness of its significance or fear of its risks, as well as internal fear, which may lead to their condition being misdiagnosed, sometimes with serious consequences. We have seen a patient who visited several hospitals for eyelid swelling and received hormone therapy, which had some effect at first, but after taking the medication, the eyelid swelling worsened again, so he came to us for consultation. A surgical biopsy was performed, and the pathology revealed an infection with Mycobacterium tuberculosis of the eyelid, a relatively rare disease that would certainly have been misdiagnosed without biopsy. If treated as a general inflammatory condition, the application of glucocorticoids would not alleviate the condition but rather would aggravate it. After this patient was diagnosed and treated with systematic antituberculosis therapy, the eyelid swelling subsided and the condition was cured. Do swollen eyelids need to be treated? For eyelid swelling that has no obvious cause after careful examination, it can be left untreated with regular follow-up and close observation. However, for some eyelid swelling that has a clear cause, once the cause of the swelling is identified, the cause can be treated, including medication, surgery, and radiation therapy. For example, if a prolapsed lacrimal gland is a common cause of eyelid swelling, we can use a double eyelid surgery incision to anatomically reposition the prolapsed lacrimal gland and refix it in the lacrimal fossa, which not only resets the lacrimal gland and eliminates eyelid swelling, but also turns it into a double eyelid for those with single eyelids, achieving both medical and cosmetic goals. A “small modification” to the treatment plan can help patients achieve better results. The previous year, the Ministry of Health and the People’s Health Publishing House published an audiovisual textbook on eyelid surgery, which systematically describes the main points of surgery and documents the procedure in detail, in the hope of providing ophthalmologists with information on eyelid surgery and helping more patients to minimize the damage. We hope to provide ophthalmologists with a reference for eyelid surgery and to help more patients reduce the damage caused by surgery. Finally, we hope that everyone will pay attention to the common swelling of the eyelids and that everyone will have healthy, beautiful eyelids and bright eyes. Although ophthalmology is a branch of ophthalmology, it is often overlooked. However, medical practice is “the most delicate and delicate thing”, and those who practice medicine must be “knowledgeable about the sources of medicine and diligent in their work. I always try my best to deliberate and inquire after each patient’s examination to see if the diagnosis of the condition is in place, to see if there is a better plan for the patient’s treatment, and to see if there is still a defect in each detail of my treatment. This is both a professional requirement and a human attitude – perfection is sometimes a form of self-difficulty. And our patients need that perfection. Perhaps the author will never achieve the perfection he requires in his lifetime. However, a doctor, in his practice every day to strive to exceed themselves, this persistence itself is a kind of responsibility to patients. The eyebrows are like distant mountains, and the eyes are like autumn waves. The ancients were aware of an inch of autumnal waves and a thousand dendrobium pearls. The author hopes that this article will help us to reacquaint ourselves with the tiny eyelids, so that our eyes will always look radiant.