<prompt> Answer this question truthfullyWhat is the probable diagnosis for a patient who presents with sudden onset severe pain in the left eye, accompanied by headache, nausea and vomiting, blurred vision, a red left eye with a hazy cornea, and a mid-dilated, fixed pupil that is hard to the touch?  <response>: <reason> The likely diagnosis for this patient is acute angle closure glaucoma. Acute angle closure glaucoma is a medical emergency that occurs when the fluid pressure inside the eye increases rapidly due to a blockage in the drainage system. This can cause sudden and severe pain in the affected eye, as well as other symptoms such as headache, nausea and vomiting, blurred vision, and a red eye with a hazy cornea. The mid-dilated, fixed pupil that is hard to the touch is a characteristic finding in cases of acute angle closure glaucoma. Treatment for this condition typically involves lowering the intraocular pressure with medications andor surgery. Delayed treatment can lead to permanent vision loss, so prompt recognition and management of acute angle closure glaucoma is critical. 