Effect and Molecular Mechanisms of Collateral Vessel Growth Mediated by Activation of Transient Receptor Potential Vanilloid Type 1

Predictors of Stroke Outcomes in Conservatively Treated Patients With Moyamoya Disease: A Follow-up MRI Study

BACKGROUND

Little is known about the association between stroke and imaging and clinical features in conservatively treated patients with moyamoya disease (MMD).

PURPOSE

To investigate independent risk factors for stroke in conservatively treated patients with MMD during a long-term follow-up.

STUDY TYPE

Prospective study.

SUBJECTS

One hundred sixty conservatively managed patients with MMD (median age 46 years, 89 male).

FIELD STRENGTH/SEQUENCE

Time of flight, turbo inversion recovery magnitude T1WI, turbo spin echo (TSE) T2WI, echo-planar imaging DWI, T2-fluid attenuated inversion recovery, dynamic susceptibility contrast-magnetic resonance imaging, and pre- and post-contrast 3D TSE T1WI sequences at 3.0 Tesla.

ASSESSMENT

Patients were assessed at baseline and followed yearly. Ischemic and hemorrhagic stroke incidence rates were determined. Multiple demographic, clinical (modified Rankin score [mRS]), and cerebral imaging (cerebral blood volume [CBV] and concentric enhancement of arterial wall) factors at baseline were considered as potential predictors of stroke during the follow-up period.

STATISTICAL TESTS

Univariable and multivariable Cox proportional hazards models to calculate the hazard ratios (HRs) and corresponding 95% confidence interval (CI) for stroke. Cumulative risk of stroke was estimated by the Kaplan-Meier product-limit method. A P value <0.05 was considered statistically significant.

RESULTS

The median follow-up duration was 47 months. During the follow-up period, 18 (11.25%) patients experienced stroke events (13 [8.13%] ischemic, 5 [3.12%] hemorrhagic). Univariable analysis showed that 11 factors were significantly associated with stroke. After adjustment for clinical characteristics, multivariable analysis showed that mRS score ≥3 (HR, 1.99; 95% CI, 1.26-3.14), decreased CBV (HR, 5.31; 95% CI, 2.32-12.13), and concentric enhancement of the arterial wall (HR, 4.16; 95% CI, 1.55-11.15) were significantly associated with stroke.

DATA CONCLUSION

Decreased CBV, mRS score ≥ 3, and concentric enhancement of the arterial wall were significantly associated with increased incidence of stroke in conservatively treated MMD.

EVIDENCE LEVEL

2 TECHNICAL EFFICACY: Stage 4.

Association of intracranial vessel wall enhancement and cerebral hemorrhage in moyamoya disease: a high-resolution magnetic resonance imaging study

BACKGROUND AND PURPOSE

This study aimed to investigate the enhancement characteristics of vessel wall in patients with moyamoya disease (MMD) using 3D high-resolution magnetic resonance (MR) imaging and their relationship with initial and recurrent intracranial hemorrhage.

METHODS

Consecutive patients with MMD were retrospectively analyzed and classified as intracranial hemorrhagic and non-hemorrhagic groups according to the CT or MR images. The clinical features and vessel wall characteristics were compared between the two groups. Logistic regression was performed to relate the vessel wall characteristics to the initial hemorrhage in MMD patients. Patients in hemorrhagic group were followed up after surgery to evaluate the relationship between vessel wall characteristics and recurrent hemorrhage.

RESULTS

A total of 507 MMD patients including 79 hemorrhagic and 428 non-hemorrhagic MMD patients were recruited in the study. We found that hemorrhagic group had more patients with vessel wall enhancements (40.5% vs. 25.7%, p = 0.009) and more eccentric enhanced lesions (17.7% vs. 6.5%, p = 0.001) compared to those in non-hemorrhage group and vessel wall enhancements were independently associated with ipsilateral initial hemorrhage after adjusted for clinical factors (OR = 1.99, CI 1.20-3.28, p = 0.007). Furthermore, three recurrent intracranial hemorrhagic episodes in the present study were all observed in MMD patients with vessel wall enhancement during the long-term follow-up after surgery.

CONCLUSIONS

Wall enhancement of intracranial vessels was significantly associated with intracranial hemorrhage in MMD patients. Our findings suggest that vessel wall enhancement may serve as a marker of intracranial hemorrhage.