1.Concept
Macular edema refers to the inflammatory reaction and fluid infiltration in the macula, the most sensitive part of the retina to light in the fundus of the eye, resulting in edema and causing severe vision loss. It is an ocular manifestation of various eye diseases such as central retinal vein obstruction, diabetic retinopathy, central plagiochoroidal retinopathy and uveitis. It is usually caused by diabetes, retinal vein obstruction, uveitis, and post-cataract IOL surgery, and is one of the important causes of vision loss.
2.Main physical signs
Irregular and blurred reflection of the central sulcus, thickening of the central sulcus combined with or without intraretinal cysts.
3.Other signs
The submacular choroidal vascular pattern cannot be seen. In severe cases, vitreous cells, optic nerve swelling and speckled hemorrhage may appear. Macular lamina fissures that cause permanent visual impairment can be formed.
4.Etiology
(1) Central plasmacytoretinal chorioretinitis.
(2) It may occur after all inner eye surgeries, including laser photocoagulation and condensation surgery. The peak incidence after cataract surgery is about 6-10 weeks postoperatively. Incidence increases with the development of surgical complications such as wound vitreous impaction, iris prolapse, and vitreous detachment.
(3) Diabetic retinopathy.
(4) Central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO).
(5) Uveitis, especially central uveitis.
(6) Retinitis pigmentosa.
(7) Use of topical eye drops: e.g. epinephrine, dipiflucan, etc., especially in patients after cataract surgery. Macular cystoid edema can often be reversed after discontinuation of the drug.
(8) Retinal vasculitis: such as retinal perivasculitis (Eales disease), Behcet’s disease, sarcoidosis, necrotizing vasculitis, multiple sclerosis, cytomegalovirus retinitis.
(9) Retinal capillary dilation, such as outer exudative retinopathy (Coats disease).
(10) Age-related macular degeneration (ARMD): usually with long-standing choroidal neovascular membrane (CNVM).
(11) Other: intraocular tumors, hypertension, connective tissue disease, autosomal inherited CMR, etc.
(12) Pseudomacular cystoid edema: FFA without leakage. Such as nicotinic maculopathy (when treating high cholesterol with relatively high doses of niacin), sex-linked hereditary retinal splitting disease, Goldmann-Fvare disease, and retinal precapillary membrane formation.
5.Examination
(1) Medical history: any recent history of internal eye surgery, history of diabetes mellitus, previous uveitis or ocular infection, family history of night blindness or ocular disease, and any history of medication use, including topical epinephrine, diphtheria, and other drugs.
(2) Detailed ocular examination, including evaluation of the peripheral fundus (pressure on the sclera is required to examine the peripheral portion). Examination of the macula is best done with a slit lamp combined with a triplet, anterior lens or 60/90D lens.
(3) FFA often shows fluorescence leakage from the capillaries around the central recess in the early stage and fluorescence staining of the macula in the late stage, typically in a petal or spoke shape. Sometimes fluorescence leakage from the optic disc is seen. Fluorescence leakage does not appear in smoker’s macular lesion.
(4) OCT examination helps to diagnose and determine the presence or absence of lamellar and total lamellar fissure formation.
(5) If indicated, other diagnostic tests can be performed, such as rapid glucose test, glucose tolerance test, ERG.
6.Therapeutic drugs
(1) Combination of Chinese and Western medicine treatment: according to the degree of lesion, give blood activation, improve microcirculation, dampness and swelling drugs, use horse chestnut seed extract, Mai Zhi Ling, Wu Ling capsule or Si Miao Wan, etc. orally.
(2) Small doses of tretinoin injection or Avastin can be used for treatment. Tretinoin (Tretinoin Injection) is administered by intramuscular injection for diseases treated with corticosteroids, such as allergic diseases (used when the patient is in a severely debilitated state and conventional drugs are ineffective), skin diseases, diffuse rheumatoid arthritis, and other connective tissue diseases. When oral corticosteroids are not feasible, intramuscular injection is effective for these diseases. Dosage, systemic: The initial recommended dose for adults is 60 mg. Depending on the patient’s response, the dose can be between 40-80 mg. However, in some patients, doses of 20 mg or less can be effective in controlling the disease. For patients with hay fever or pollen-induced asthma, when desensitization therapy or other traditional therapies do not work, 40-100 mg can be administered in a single injection during the pollen season, which should be administered deep into the gluteal muscles for effective absorption of the drug. In recent years, small doses of this drug have been used for posterior bulb or intravitreal injection to treat macular edema, with certain efficacy. Usually a single topical dose of tretinoin can effectively relieve symptoms, but sometimes multiple doses are required. There is individual variation in patient response after treatment: sometimes one or two doses can provide prolonged relief; sometimes a second dose is needed several months later. (This drug should not be used for a long time to avoid side effects and complications.)
(3) Others: Cytarabine sodium tablets or capsules and luteolin, Deferoxamine tablets, etc. can be taken orally.