Many people think that if you have glaucoma, you must have red eyes, and that red eyes must be glaucoma, is that true? Actually, no. The redness of the eye can be caused by either congestion of the conjunctiva or subconjunctival hemorrhage. Under normal circumstances, the blood vessels in the bulbar conjunctiva are in a “sleepy” state, with only a small amount of blood passing through them, so the bulbar conjunctiva and sclera always appear to be white and unblemished. When invaded by foreign forces such as bacteria and viruses, the “sleeping” blood vessels wake up and expand, resulting in congestion in the eyes. There are two common types of eye congestion: superficial congestion and deep congestion. The former is bright red and is called “conjunctival congestion”; the latter is dark red and is called “ciliary congestion”. If both are present, it is called “mixed congestion”. These different conditions of congestion are very meaningful in the examination and diagnosis of doctors, and are also one of the important bases for determining the severity of eye disease, but it is difficult for laymen to distinguish them clearly. Subconjunctival hemorrhage is the result of blood deposited under the bulbar conjunctiva due to the rupture of the bulbar conjunctival vessels for various reasons. Common eye diseases that cause redness include acute and chronic conjunctivitis, keratitis, iridocyclitis, scleritis, glaucoma, chemical burns of the eye, and subconjunctival hemorrhage. (1) Subconjunctival hemorrhage Causes: Most of them are caused by diabetes, hypertension atherosclerosis, poor coagulation and local vascular inflammation or increased vascular fragility, love of irritating food, forceful breath-holding, trauma, heavy physical labor, constipation, and long-term strenuous exercise. Symptoms: Patients usually do not have any discomfort, and occasionally have mild soreness and distension, which is often known only when they unintentionally look in the mirror or are noticed by bystanders. Signs: Punctate or patchy hemorrhage is seen on the bulbar conjunctiva, which does not recede with pressure and is bright red when fresh or dark red in more aged cases. Treatment: This disease has a good prognosis, can take oral vitamin C, compound luting tablets, if there is hypertension can take antihypertensive drugs, fresh bleeding when feasible ice or cold compresses, bleeding stable after the switch to hot compresses to promote the absorption of blood clots, generally 1 to 3 weeks will subside on its own. (2) acute conjunctivitis Etiology: a common epidemic eye disease caused by bacterial and viral infections, highly contagious. Symptoms: Rapid onset, simultaneous or sequential onset in both eyes, stinging, itching, foreign body sensation in the affected eye, photophobia and burning sensation in severe cases, vision is generally unaffected. Signs: redness and swelling of the eyelids, conjunctival congestion, and discharge. In bacterial infections, the secretions are often mucous or purulent, and the eyes are stuck with secretions in the morning; in viral infections, the secretions are mostly aqueous and may be accompanied by corneal lesions, enlarged lymph nodes in front of the ear and under the jaw, and pressure pain. Treatment: The disease is highly contagious and should be prevented by isolation, towels and handkerchiefs should not be used with each other, and the basin should be rinsed and disinfected after use. Keep the eyes clean, use water or go to the hospital to flush when there is a lot of secretions, and use local antibiotics and antiviral drugs. If there are systemic symptoms such as fever, headache, etc., combine with medical treatment. (3) Acute iridocyclitis Etiology: The cause of iridocyclitis is complex, and most of the causes are unknown and may be related to autoimmune diseases such as rheumatism as well as tuberculosis, syphilis, and viral infections. Symptoms: Vision loss with marked photophobia, tearing, and ocular pain that may radiate to the brow arch, temporal region, and frontal region. Signs: ciliary congestion or mixed congestion, posterior corneal deposits (referred to as KP), cloudy atrial fluid, indistinct iris texture, obscure color, reduced or irregular pupil, blunted light reflex, and posterior adhesion of some iris to the lens; IOP is generally normal, but sometimes increased or decreased. Treatment: Active search for the cause and treatment of the cause. Local pupil dilation with 1% atropine eye water, hot compresses, hormonal eye drops or subconjunctival injections, systemic intravenous or oral hormones and anti-inflammatory pain medications are required for severe cases. (4) Keratitis Etiology: Most keratitis is caused by foreign infections. Minor corneal trauma is often the causative agent of infection. The common causative agents are bacteria, fungi, viruses, etc. In addition, corneal immune insufficiency or malnutrition can cause keratitis. Symptoms: pain in the affected eye, foreign body sensation, eyelid spasm, photophobia, lacrimation, sudden loss of vision, etc. Signs: Different causes of keratitis have their own characteristics, but the basic signs are eyelid spasm and edema, mixed conjunctival congestion with edema, clouding of the cornea or ulcer formation, precipitates visible behind the cornea, and pus accumulation in the anterior chamber. Treatment: The first step in treating keratitis is to remove the cause. Most keratitis is caused by infection, so it is important to use appropriate antibacterial and antiviral medications. We can use the different clinical features of various keratitis, smear staining of secretions or ulcerated tissue and bacterial culture. Drug sensitivity test, etc., to clearly diagnose the cause of the disease. In case of bacterial keratitis, broad-spectrum antibacterial drugs can be used, such as those caused by Pseudomonas aeruginosa, tobramycin, polymyxin and mucomycin can be added. For fungal keratitis, antifungal drugs such as dicloxacillin B are available. Viral keratitis can be treated with acyclic guanosine, virazole, etc. The route of administration can be local drops or subconjunctival injection. This can be supplemented with 1% atropine eye water to dilate the pupil, paralyze the ciliary muscle to relieve pain, prevent post-iris adhesions and reduce the local inflammatory response. If the cause is difficult to determine, broad-spectrum antibacterial drugs or a combination of antibacterial drugs can be used. (5) Acute angle-closure glaucoma Etiology: The cause is complex, mostly occurs in middle-aged and elderly women, and is a bilateral disease, which can develop in both eyes successively or simultaneously, and is related to genetics. It is mainly due to anatomical abnormalities of the eye, resulting in obstruction of atrial aqueous drainage and elevated intraocular pressure. Symptoms: Sudden loss of vision, severe pain in the eye with ipsilateral migraine, and systemic symptoms such as nausea and vomiting, etc. Ocular symptoms are often overlooked due to systemic symptoms and are misdiagnosed as gastrointestinal diseases, hypertension and other systemic diseases. Signs: Eyelid and bulbar conjunctiva edema, significant mixed congestion in the bulbar conjunctiva, cloudy corneal edema, extremely shallow anterior chamber, iris edema, dilated pupils, loss of light reflex, high intraocular pressure, which can be greater than 60 mmHg. Treatment: Acute angle-closure glaucoma has a rapid onset, and the condition is serious and can lead to blindness within a short period of time, so it should be rescued in a timely manner, and the intraocular pressure should be controlled within 24-48 hours if possible. In principle, the IOP should be controlled with drugs first, and surgery should be used as soon as possible. The main drugs used to lower IOP are 20% mannitol solution, 50% glycerol, acetazolamide tablets, maurozanthine, and local b-blockers. Among all types of primary and secondary glaucoma, only a few types of glaucoma can show symptoms of red eyes, such as acute closed-angle glaucoma, glaucoma secondary to inflammation, etc. At the same time, there are many types of glaucoma that do not have symptoms of red eyes, such as primary chronic closed-angle glaucoma, primary open-angle glaucoma, etc.; moreover, from the knowledge we have talked about above, we can also know that red eyes It is not necessarily glaucoma. Therefore, we should not think that we do not have glaucoma just because our eyes are not red, nor should we think that we have glaucoma just because our eyes are red, but we must seek a specialist for a comprehensive and detailed examination before we can draw a correct conclusion.