Blurred vision may be due to vision loss and ageing, but it may also be a sign of some diseases, and more diseases that can trigger blurred vision, the following eight common diseases: 1, eye diseases 1, refractive error: which contains myopia, hyperopia, astigmatism three diseases, the disease may appear after the symptoms of blurred vision, vision loss; 2, cataract: mostly seen in the elderly, the onset of patients The onset of the disease may cause blurred vision due to increased intraocular pressure and cloudy lens deformation, and with the aggravation of the disease, the visual field will be obscured; 3. chronic diseases such as hypertension, eye trauma, etc., resulting in light not being properly placed on the retina and therefore may trigger blurred vision. Second, cranio-cerebral diseases 1, cerebral hemorrhage: mostly seen in patients with acute onset, the onset of sudden weakness of limbs, crooked eyes and mouth, drooling, blurred vision, nausea, vomiting and other symptoms; 2, other: such as cranial occupational lesions, may be in the cranial compression of the optic nerve, which in turn leads to blurred vision, most patients are accompanied by drowsiness, headache and other symptoms. 3, systemic pathology 1, hypertensive emergencies: mostly seen in patients with elevated blood pressure greater than 180/120mmHg in a short period of time, the onset of blurred vision, in addition to obvious headache, dizziness, chest tightness, dyspnea and other symptoms, some patients may have visual impairment, abdominal pain and other symptoms; 2, diabetes: diabetic patients with poor blood sugar control or diabetic retinopathy may cause blurred vision and are usually accompanied by skin infections, vision changes and other symptoms. Therefore, for patients with sudden blurred vision, it is recommended to go to the hospital for detailed examination in order to clarify the diagnosis and treat the symptoms in a timely manner. Patients with a previous history of the disease should be reviewed regularly to be alert to changes in their condition.