Central plasma retinal chorioretinopathy, or “mesoplasia” for short, is one of the most common clinical fundus diseases. In recent years, there has been a lot of research on mesoplasia, and clinicians have become more knowledgeable about the disease, so today we are going to share with you some things about mesoplasia. Is mesoplasia common? Is it as common as we think in clinical practice? There is no epidemiological study on the incidence of mesoplasia in China, and a related study in the United States found that the incidence of mesoplasia is at 5.8/100,000 people. Clinically, many doctors diagnose mesoplasia when they see macular exudation. In fact, the diagnosis of mesoplasia requires caution, especially in the following two cases: 1. The diagnosis of mesoplasia in the elderly The onset of mesoplasia is closely related to hormone levels, so the elderly are not a high-incidence group. Clinical diagnosis of suspected cases in the elderly should be cautious, especially excluding AMD and not PCV, which are two easily confused diseases. In elderly people with a high degree of suspicion of M.P., detailed questions should be asked about any major psychological stimuli in their lives. Is there a history of hormone application? If necessary, a whole body examination should be performed to exclude endogenous hormone elevation caused by other diseases. 2. Patients with severe vision loss Patients with mesoplasia have vision loss, but the average visual acuity is 0.3~0.7. If the visual acuity of the patient is clinically reduced to less than 0.1, the diagnosis should be quite cautious, and the visual acuity results should be verified in detail, and other macular diseases should be carefully excluded. Three tests must be done for patients with mesoplasia In order to judge the condition of a patient with mesoplasia and guide the treatment, three tests are essential. 1. OCT examination, which can visualize the size and extent of fluid accumulation in the macula, is an important basis for diagnosis. 2. fluorescence angiography (FA): it can visualize the leakage points in the RPE layer, which is an important indicator of the activity of mesoplasia. 3. choroidal angiography (ICGA). Many physicians neglect to perform chorioretinography on their patients, which is not correct. Since the main pathological change of mesoplasm is the vasodilatation of the choroid, choroidogram can effectively determine the extent of the lesion and is an important reference to guide the treatment of PDT. Is the mesoplasm self-limiting? Why do I need to treat it? As many medical students know, the first thing that comes to mind when mentioning “self-limiting diseases” in ophthalmology is mesangial pulp, but does it really heal on its own? A study conducted by Prof. Albert Chan from Hong Kong tells us that the self-limiting rate of C.P. is only 57.9%; and most of the patients will relapse and lose their vision again after a period of improvement. And the study showed that the function of the optic cells will change after more than 4 months of prolongation of the disease in patients with mesoplasia, causing irreversible vision loss. From these results, it is important to treat mesophoria aggressively; clinically, patients often report that vision loss, visual distortion, and central dark spots have a significant impact on work and life. Therefore, we advocate that patients who see mid-pulp in clinical practice should be treated aggressively. Half-dose PDT is currently the treatment of choice. It has been found that the cure rate of acute mesophoria is about 95% and the cure rate of chronic mesophoria is about 85% after active treatment, therefore, in clinical practice, we should actively communicate with patients before treatment, not all patients can be completely cured.