Glaucoma is often an invisible disease, as the more common open angle from has no symptoms until some vision loss is noted by the patient. That loss is not recoverable.
Acute angle closure does have recognizable. Acute angle closure does has recognizable symptoms, including intense pain in the eye, headache, possible nausea and vomiting, blurry or decreased vision and sensitivity to light, possible with rainbows appearing around lights. These symptoms are serious, and urgent care should be sought immediately.
Congenital glaucoma is recognized by an enlarged cornea, sensitivity to light and tearing of the eye.