Test your medicine knowledge with the MKSAP challenge, in partnership with the American College of Physicians.

A 76-year-old woman is evaluated for a 1-day history of headache, left eye pain, nausea and vomiting, seeing halos around lights, and decreased visual acuity of the left eye. She has type 2 diabetes mellitus, hypertension, and atrial fibrillation. Medications are metformin, digoxin, metoprolol, hydrochlorothiazide, and warfarin.

On physical examination, temperature is 36.8 °C (98.2 °F), blood pressure is 148/88 mm Hg, pulse rate is 104/min, and respiration rate is 16/min. Visual acuity wearing glasses is 20/40 (right eye) and 20/100 (left eye). The left eye has conjunctival erythema. The right pupil is reactive to light, the left pupil is sluggish and constricts in response to light from 6 mm to 4 mm. On palpation of the ocular globe, the left globe feels firm as compared with the right.

Which of the following is the most likely diagnosis?

A: Acute angle-closure glaucoma
B: Central retinal artery occlusion
C: Ocular migraine
D: Temporal arteritis

MKSAP Answer and Critique

The correct answer is A: Acute angle-closure glaucoma.

This patient most likely has acute angle-closure glaucoma. Angle-closure glaucoma is characterized by narrowing or closure of the anterior chamber angle, which impedes the trabecular drainage system in the anterior chamber, resulting in elevated intraocular pressure and damage to the optic nerve. Acute angle-closure glaucoma is an ophthalmologic emergency.

Symptoms depend upon the rapidity of the elevation of intraocular pressure. Typical history of acute angle-closure glaucoma may include seeing halos around lights, severe unilateral eye pain, headache, and nausea and vomiting. Occasionally, patients may present with only nausea and vomiting and be mistaken as having cardiac or abdominal pathology. Physical examination may show conjunctival erythema; a sluggish or nonreactive, mid-range dilated pupil; corneal cloudiness; and, on funduscopic examination, cupping of the optic nerve. Treatment in this case would be immediate referral to an ophthalmologist or emergency department for initiation of topical β-adrenergic antagonists and pilocarpine and carbonic anhydrase inhibitors.

Central retinal artery occlusion (CRAO) classically presents in a 50- to 70-year-old patient as a painless, abrupt loss of vision that occurs in the early morning hours—usually between midnight and 6 am and, second most commonly, between 6 am and noon. It results from an embolic or thrombotic event in the ophthalmic artery. Although this patient is at risk for CRAO owing to her atrial fibrillation, CRAO would not cause red eye, a firm globe, ocular pain, nausea, or vomiting.

Ocular migraine, also known as retinal migraine, typically occurs in persons with a family history or personal history of migraine, which this patient does not have. Symptoms include flashing lights, scintillating scotomas, visual blurring, and even total unilateral vision loss. Patients with ocular migraine tend to be younger than 40 years, making this diagnosis highly unlikely in this 76-year-old patient.

Temporal arteritis should be considered in patients older than 50 years presenting with a severe new headache. Visual loss in temporal arteritis is painless, however, and would not cause a red eye, nausea, or vomiting.

Key Point

• Acute angle-closure glaucoma is characterized by severe unilateral eye pain, headache, nausea and vomiting, and seeing halos around lights; physical examination findings include conjunctival erythema; a sluggish or nonreactive, mid-range dilated pupil; corneal cloudiness; and cupping of the optic nerve.

This content is excerpted from MKSAP 16 with permission from the American College of Physicians (ACP). Use is restricted in the same manner as that defined in the MKSAP 16 Digital license agreement. This material should never be used as a substitute for clinical judgment and does not represent an official position of ACP. All content is licensed to KevinMD.com on an “AS IS” basis without any warranty of any nature. The publisher, ACP, shall not be liable for any damage or loss of any kind arising out of or resulting from use of content, regardless of whether such liability is based in tort, contract or otherwise.