Patients with conjunctival hemorrhage are generally considered to be caused by the rupture of blood vessels under the bulbar conjunctiva, or increased permeability, and the surrounding boundaries are very clear, red is red, white is white, the boundaries are very clear, generally more common in one eye, any age can be seen, and increased abdominal pressure, trauma, disease, as follows: 1, increased abdominal pressure: young people may have a cough, vomiting after drinking alcohol, may be more common, age In older people, it may be associated with high blood pressure, vascular sclerosis, breath-holding when exercising, and violent coughing when there is an infection in the lungs can cause conjunctival hemorrhage. 2. Trauma: Patients who have received a direct blow to the eye or a crushing injury to the head can cause subconjunctival hemorrhage. 3. Diseases: Inflammation of the conjunctiva, such as viral conjunctivitis, in addition to some blood diseases, and certain infectious diseases may also cause conjunctival hemorrhage. . In fact, most of the conjunctival hemorrhage can not be found the exact cause, usually 7-12 days will be self-absorption. If there are recurrent episodes, it may be necessary to focus on identifying whether there are systemic diseases in the body and to do a systematic examination.