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Article | AAO 2026

When Retinal Findings Point to a Vascular Emergency

How to respond to high blood pressure, Hollenhorst plaques, and other vascular findings.

By: Sarah Fackler, managing editor, Optometric Management
Optometric Management October 2, 2026

A high blood pressure reading, sudden vision loss, and a Hollenhorst plaque can each signal vascular disease, but they call for different responses from optometrists. Andy Rothstein, OD, and Mark Swanson, OD, MSPH, FAAO, addressed those decisions in “Blood Pressure, Hollenhorst Plaque, Transient Ischemic Attack and Stroke: What’s an OD to Do” at the American Academy of Optometry annual meeting in Anaheim, California.

Interpreting Blood Pressure in the Office

A single office blood pressure measurement may not represent a patient’s usual pressure, Drs. Rothstein and Swanson began. They explained that readings vary by an average of 12 mmHg between measurements, and variability can reach 32 mmHg at higher systolic pressures. Factors such as an unsupported back, recent smoking, a full bladder, pain, and the clinical setting can affect the result.

Drs. Rothstein and Swanson distinguished severe asymptomatic hypertension from a hypertensive emergency. The latter involves blood pressure above 180/120 mmHg with new or progressive target-organ damage. Symptoms such as headache, chest pain, breathing difficulty, or urinary problems warrant assessment, and concerning systemic symptoms or retinal findings call for emergency referral. For a patient without such findings after an initially severe measurement, they recommend waiting 30 minutes and rechecking, then communicating with or arranging follow-up with the patient’s medical provider.

The retinal examination helps inform that decision. Arteriolar narrowing, arteriovenous nicking, and vessel wall changes can reflect chronic disease. Hemorrhages, microaneurysms, cotton wool spots, and hard exudates are classified as moderate hypertensive retinopathy, while optic disc swelling with severe hypertension is a more urgent finding. Drs. Rothstein and Swanson also cautioned that hemorrhages and cotton wool spots require consideration and ruling out of diabetes and other causes.

Treat Retinal Artery Occlusion as a Stroke

They stressed throughout the presentation that retinal artery occlusion (RAO) is a stroke. Central retinal artery occlusion (CRAO) occurs at an estimated rate of 2 cases per 100,000 person-years, compared with 5 cases per 100,000 person-years for branch retinal artery occlusion (BRAO).1

Sudden, painless vision loss in 1 eye is a key symptom, Drs. Rothstein and Swanson explained. Approximately 75% of patients with CRAO present with counting-fingers vision or worse, whereas 74% of patients with BRAO have acuity of 20/40 or better, according to figures cited in the presentation.2-3 In the first minutes to hours, the retina may appear normal, but later findings can include retinal whitening, a cherry-red spot, attenuated arterioles, and an embolus, among others.

When onset is within 72 hours Drs. Rothstein and Swanson recommended immediate referral with clinical notes to a comprehensive, level 1 stroke center for recent RAO. For presentations after 72 hours, the management flow calls for an urgent outpatient stroke work-up coordinated with the primary care physician, provided there are no red flags such as neurologic symptoms, possible giant cell arteritis (GCA), recurrent symptoms, or an uncertain timeline.

That workup matters beyond the affected eye, they added. Up to 24% of patients with RAO have a concurrent brain stroke and that brain stroke risk is 33 times higher following CRAO, particularly in the first 2 weeks.4-5 They also identified GCA as a cause of approximately 5% of CRAO cases6 and emphasized evaluation for symptoms such as headache and jaw claudication. Normal blood work does not rule out GCA, they noted.

Whether thrombolysis improves visual outcomes in CRAO remains uncertain. Drs. Rothstein and Swanson described recent trial results as inconclusive7 and said its potential benefits and risks should be weighed case by case at the stroke center.

Distinguish a Plaque From an Occlusion

A Hollenhorst plaque is a cholesterol embolus that commonly originates from the carotid arteries or heart. Drs. Rothstein and Swanson reported that 75% of these plaques are asymptomatic. Moderate carotid stenosis has been reported in 25% of patients who had Hollenhorst plaques and severe stenosis in 13% of these patients, according to cited studies.8-9

An asymptomatic Hollenhorst plaque is not an emergency, the presenters said, but it still requires cardiovascular evaluation. They recommend referral to the patient’s primary care physician for risk reduction and a workup that includes carotid assessment. A plaque accompanied by transient visual loss or other ischemic symptoms requires evaluation according to the symptomatic pathway.

Drs. Rothstein and Swanson also addressed transient ischemic attack (TIA), which can involve retinal ischemia without acute infarction. There is an average 10% risk of stroke within 90 days after TIA10, they said, and most subsequent strokes occur within the first 2 days. For symptoms within the preceding 48 hours, they recommended sending the patient directly to the emergency department and alerting the stroke team.

 

References

  1. Chen C, Singh G, Madike R, Cugati S. Central retinal artery occlusion: a stroke of the eye. Eye (Lond). 2024;38(12):2319–2326. doi:10.1038/s41433-024-03029-w

  2. Hayreh SS. Ocular vascular occlusive disorders: natural history of visual outcome. Prog Retin Eye Res. 2014;41:1-25. doi:10.1016/j.preteyeres.2014.04.001

  3. Justice J Jr, Lehmann RP. Cilioretinal arteries. A study based on review of stereo fundus photographs and fluorescein angiographic findings. Arch Ophthalmol. 1976;94(8):1355-1358. doi:10.1001/archopht.1976.03910040227015

  4. Stuart A, Lee AG, Levin MH, Miller NR. CRAO: harbringer of ischemic stroke. EyeNet Magazine. June 1, 2016. Accessed September 28, 2026. https://www.aao.org/eyenet/article/crao-harbinger-of-ischemic-stroke

  5. French D, Margo CE, Greenberg PB. Ischemic stroke risk in Medicare beneficiaries with central retinal artery occlusion: a retrospective cohort study. Ophthalmol Ther. 2018;7(1):125-131. doi:10.1007/s40123-018-0126-x

  6. Hayreh SS, Zimmerman MB. Central retinal artery occlusion: visual outcome. Am J Ophthalmol. 2005;140(3):376–391. doi:10.1016/j.ajo.2005.03.038

  7. Prabhakaran S, Gonzalez NR, Zachrison KS, et al. 2026 guideline for the early management of patients with acute ischemic stroke: a guideline from the American Heart Association/American Stroke Association. Stroke. 2026;57(8). doi:10.1161/STR.0000000000000513

  8. de Weerd M, Greving JP, de Jong AWF, Buskens E, Bots ML. Prevalence of asymptomatic carotid artery stenosis according to age and sex: systematic review and metaregression analysis. Stroke. 2009;40(4):1105-1113. doi:10.1161/STROKEAHA.108.532218

  9. Bakri SJ, Luqman A, Pathik B, Chandrasekaran K. Is carotid ultrasound necessary in the evaluation of the asymptomatic Hollenhorst plaque? Ophthalmology. 2013;120(12):2747-2748.e1. doi:10.1016/j.ophtha.2013.09.005

  10. Johnston SC, Rothwell PM, Nguyen-Huynh MN, et al. Validation and refinement of scores to predict very early stroke risk after transient ischaemic attack. Lancet. 2007;369(9558):283–292. doi:10.1016/S0140-6736(07)60150-0