A 68-year-old man reports three episodes of painless loss of vision in the right eye lasting about 10 minutes each, with complete recovery between episodes. Fundus examination shows a small glistening refractile particle lodged at a retinal arteriolar bifurcation superior to the disc. Which investigation is most appropriate next?
- A Temporal artery biopsy
- B Intravenous fluorescein angiography
- C Carotid Doppler ultrasonography ✓
- D Serum homocysteine levels
Correct answer: C. Carotid Doppler ultrasonography
Explanation
Recurrent transient monocular visual loss with a Hollenhorst plaque, a glistening cholesterol embolus arising from an atherosclerotic carotid bifurcation, indicates embolic amaurosis fugax. The source is almost always the ipsilateral carotid artery, so carotid Doppler is the correct next step to quantify stenosis and guide endarterectomy decisions. Temporal artery biopsy is reserved for suspected giant cell arteritis, which causes persistent rather than fleeting vision loss in older patients with systemic symptoms.
Reference: AAO Basic and Clinical Science Course, Section 12: Retina and Vitreous, 2023-2024 ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.