Ipsilateral plaques display higher T1 signals than contralateral plaques in recently symptomatic patients with bilateral carotid intraplaque hemorrhage
Xianling Wang1, Jie Sun2, Xihai Zhao3
1Department of Radiology, University of Washington, Seattle, WA, USA; Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China.
Insights
Carotid intraplaque hemorrhage (IPH) detected by MRI is linked to stroke. Symptomatic IPH plaques show stronger T1 signals, larger necrotic cores, and longer length compared to asymptomatic ones, aiding in risk assessment.
Area of Science:
- Neurology
- Cardiovascular Imaging
- Radiology
Background:
- Carotid intraplaque hemorrhage (IPH) detected via MRI is associated with cerebrovascular events.
- IPH is also found in asymptomatic individuals, necessitating differentiation between symptomatic and asymptomatic plaques.
Purpose of the Study:
- To investigate differences in plaque characteristics between symptomatic and asymptomatic sides in patients with bilateral carotid IPH.
Main Methods:
- Patients with recent ischemic events and bilateral IPH underwent standardized MRI.
- Analysis included T1/T2 signals, plaque morphology, and coexisting characteristics of symptomatic vs. asymptomatic sides.
Main Results:
- Symptomatic IPH plaques exhibited stronger T1 signals (SIRIPH-to-muscle: 5.8 vs. 4.7, p=0.004) and tended to be more extensive (volume: 150 vs. 88 mm3, p=0.071).
- Symptomatic plaques were longer (24 vs. 21 mm, p=0.026) and had larger necrotic cores (406 vs. 291 mm3, p=0.039) than asymptomatic ones.
Conclusions:
- In patients with bilateral carotid IPH and recent symptoms, the symptomatic side displays distinct imaging features.
- These findings suggest that specific IPH characteristics may hold diagnostic and prognostic value beyond the mere presence of IPH.
Background And Aims:
Prospective studies have shown a strong association between carotid intraplaque hemorrhage (IPH), detected by magnetic resonance imaging (MRI), and cerebrovascular ischemic events. However, IPH is also observed in a substantial number of asymptomatic patients. We hypothesized that there are differences in the characteristics of IPH+ plaques associated with recent symptoms, compared to IPH+ plaques not associated with recent symptoms.
Methods:
Patients with recent (≤2 weeks) anterior circulation ischemic events were scanned using a standardized multisequence protocol. Those showing IPH bilaterally were included and analyzed for differences in T1/T2 signals, plaque morphology, and coexisting plaque characteristics between the ipsilateral symptomatic and contralateral asymptomatic sides.
Results:
Thirty-one subjects (67 ± 9 years, 97% males) with bilateral IPH were studied. Despite comparable luminal stenosis (53 ± 42% vs. 53 ± 39%, p = 0.99), T1 signal of IPH measured as signal-intensity-ratio compared to muscle was stronger (SIRIPH-to-muscle: 5.8 ± 2.4 vs. 4.7 ± 1.8, p = 0.004) and tended to be more extensively distributed (IPH volume: 150 ± 199 vs. 88 ± 106 mm3, p = 0.071) on the symptomatic side. IPH+ plaques on the symptomatic side were longer (24 ± 6 vs. 21 ± 7 mm, p = 0.026) and associated with larger necrotic core volume (406 ± 354 vs. 291 ± 293 mm3, p = 0.039) than those on the asymptomatic side.
Conclusions:
In recently symptomatic patients with bilateral carotid IPH, the symptomatic side showed stronger T1 signals, larger necrotic cores, and longer plaque length than the asymptomatic side. Serial studies on the temporal relationship between these imaging features and clinical events will eventually establish their diagnostic and prognostic value beyond the mere presence of IPH.
