Unlike chronic open angle glaucoma, acute glaucoma often has very marked symptoms, such as severe pain in the eye, blurred vision, the appearance of halos around lights, and vomiting. This type of glaucoma, which is present at birth, is rare. Enlargement of the infant's eyes as well as tearing and unusual sensitivity to light are symptoms that indicate the need for an ophthalmological examination. In most cases, there are no symptoms. Damage can progress so slowly that the person is not aware of the gradual loss of sight.
Vision usually becomes more and more impaired until, finally, irreversible blindness sets in.
Some people do experience vague symptoms, and these are important warnings that a thorough eye examination is needed. Symptoms can include a need for frequent change in glasses, difficulty in adjusting to dark rooms, loss of side vision, and blurred vision. Rarely, other symptoms, such as the appearance of halos or rainbows around lights and severe headaches or pain, may occur. Glaucoma is diagnosed with a painless pressure measurement of the eye. A very rare form of glaucoma can occur in infants.