Same lesion, different outcomes: hemodynamic correlates of ischemic stroke in unilateral high-grade internal carotid artery stenosis or occlusion - a retrospective transcranial Doppler study.
Jia Y, Huo T, et al. • Frontiers in neurology • 2026
In patients with high-grade stenosis or occlusion of unilateral ICA, hemodynamic parameters measured by TCD—specifically lower ipsilateral MCA flow velocity, higher PCA-P2 flow velocity, and reversal of ophthalmic artery flow—were identified as factors associated with the presence of ischemic stroke.
Key Findings
Results
Lower ipsilateral middle cerebral artery (MCA) flow velocity was associated with the presence of ischemic stroke in patients with unilateral high-grade ICA stenosis or occlusion.
272 patients with high-grade stenosis or occlusion of unilateral ICA were retrospectively enrolled and divided into a stroke group and a non-stroke group.
Binary logistic regression was used to identify MCA flow velocity as an independent factor associated with IS.
Lower MCA flow velocity on the ipsilateral side was specifically associated with ischemic stroke occurrence.
Trend tests were used alongside binary logistic regression to analyze the data.
Results
Higher flow velocity in the P2 segment of the posterior cerebral artery (PCA-P2) was associated with the presence of ischemic stroke.
PCA-P2 flow velocity was measured by transcranial Doppler ultrasound (TCD) as part of the hemodynamic assessment.
Higher PCA-P2 flow velocity was identified as a factor associated with IS using binary logistic regression.
Elevated PCA-P2 velocity may reflect compensatory collateral flow in the setting of ICA compromise.
The finding was derived from a retrospective cohort of 272 patients.
Results
Reversal of ophthalmic artery flow (ROAF) was identified as a hemodynamic factor associated with the presence of ischemic stroke.
ROAF was detected by TCD as part of the hemodynamic parameter evaluation.
ROAF was included among the TCD parameters identified by binary logistic regression as associated with IS.
Reversal of ophthalmic artery flow is a known indicator of severely compromised ICA hemodynamics.
Data were collected retrospectively from baseline TCD and duplex scan examination of neck vessels.
Results
Patients with high-grade unilateral ICA stenosis or occlusion experienced varying outcomes, with cerebral hemodynamics measured by TCD differentiating those who had ischemic stroke from those who did not.
A total of 272 patients were enrolled, divided into a stroke group and a non-stroke group based on the presence or absence of IS at the index admission.
Baseline data, laboratory examination results, TCD, duplex scan of neck vessels, and imaging information were all collected.
The study design was retrospective, which the authors acknowledged as a limitation requiring prospective validation.
The authors stated that 'prospective studies are warranted before these TCD parameters can be applied to guide the timing of intervention for ICA lesions.'
What This Means
This research suggests that in patients who have a severe narrowing or blockage of the internal carotid artery (ICA)—a major blood vessel supplying the brain—not everyone experiences a stroke, and the differences in blood flow patterns within the brain may help explain why. Researchers used transcranial Doppler ultrasound (TCD), a non-invasive tool that measures blood flow velocities in brain arteries, to study 272 patients with this condition. They found that patients who had suffered a stroke tended to have lower blood flow velocity in the middle cerebral artery on the same side as the ICA problem, higher blood flow in a branch of the posterior cerebral artery, and a reversed flow pattern in the ophthalmic artery—all signs of more severely compromised brain circulation.
These findings suggest that TCD-measured blood flow patterns could potentially help identify which patients with severe ICA disease are at higher risk of stroke. The idea is that when the brain's main blood supply is critically reduced (shown by low MCA velocity) and collateral vessels are working hard to compensate (shown by high PCA-P2 velocity and reversed ophthalmic artery flow), a stroke is more likely to have occurred. This could have implications for deciding when to intervene surgically or with other treatments to restore normal blood flow.
However, because this was a retrospective study—meaning it looked back at existing patient records rather than following patients forward in time—the authors caution that prospective studies are needed before these TCD measurements can be reliably used to guide treatment decisions. The research adds to the understanding of why the same type of artery blockage can lead to very different outcomes in different people.
Jia Y, Huo T, Fan M, Zhang J, Teng Z, Chen W, et al.. (2026). Same lesion, different outcomes: hemodynamic correlates of ischemic stroke in unilateral high-grade internal carotid artery stenosis or occlusion - a retrospective transcranial Doppler study.. Frontiers in neurology. https://doi.org/10.3389/fneur.2026.1892791