Vessel Wall MRI Added to MR Angiography in the Evaluation of Suspected Vasculopathies.

BACKGROUND AND PURPOSE: We hypothesized that vessel wall MR imaging (VWI) with 3D-time-of-flight magnetic resonance imaging (3D-TOF-MRA) together increases the ability to detect abnormal intracranial vessel segments compared to 3D-TOF-MRA alone. METHODS: Ninety-three consecutive subjects with a clinical history of suspected vasculopathy imaged with both VWI and 3D-TOF-MRAs were retrospectively reviewed. The 3D-TOF-MRAs were reviewed by two independent neuroradiologists classifying arterial segments as normal or abnormal based on caliber changes. Following a 2-week wash-out period, the 3D-TOF-MRAs with VWI together were re-evaluated for caliber changes and/or vessel wall enhancement. A third neuroradiologist served as consensus. Significance was assessed by McNemar's test. RESULTS: Forty-two subjects with VWI and 3D-TOF-MRAs met the inclusion criteria. By 3D-TOF-MRA alone, 12.3% (95% confidence interval [CI], 10.7-15.1) of the arterial segments were identified as abnormal compared to 20.8% (95% CI, 18.2-23.4) by VWI and 3D-TOF-MRA together (P < .0001). CONCLUSIONS: 3D-TOF-MRA and VWI together identifies a higher number of abnormal vessel segments than 3D-TOF-MRA alone and may provide a more accurate assessment of disease burden.

Spatial Distribution of Intracranial Vessel Wall Enhancement in Hypertension and Primary Angiitis of the CNS.

We hypothesized a difference in the spatial distribution of intracranial vessel wall enhancement between CNS vasculitis and risk factors for intracranial atherosclerotic disease (ICAD). Fifty-five vessel wall MR imaging (VWI) exams were included in this retrospective observational study. Intracranial arteries were evaluated for vessel wall enhancement by branching pattern (e.g., primary, secondary, and tertiary segments). Demographic and laboratory data as well as ICAD risk factors, including a diagnosis of hypertension, were collected. A diagnosis of primary angiitis of the CNS (PACNS) was confirmed by biopsy or clinical assessment by a stroke neurologist. Univariate and multivariate Poisson regression models were fit for the outcomes. In multivariate analyses, hypertension showed significant associations with primary (ß = 1.31, 95% CI 0.78-1.88, p < 0.0001) and secondary (ß = 1.15, 95% CI 0.29-2.18, p = 0.05) segments, contrasting with PACNS which showed a distal spatial distribution with significant associations with secondary (ß = 0.77, 95% CI 0.14-1.39, p = 0.05) and tertiary (ß = 1.34, 95% CI 0.68-2.01, p < 0.0001) segments. Our results suggest the spatial distribution of vessel wall enhancement is an important consideration when interpreting VWI exams, particularly in patients with a comorbid diagnosis of hypertension. Given the global prevalence of hypertension, these results are impactful and may improve image interpretation of VWI in stroke patients.

High resolution vessel wall MR imaging in prestenotic intracranial atherosclerotic disease.

Vessel wall MR imaging (VWI) may be able to highlight vulnerable intracranial atherosclerosis with vessel wall enhancement thereby serving as a biomarker for symptomatic prestenotic intracranial atherosclerotic disease. We present a case of intracranial hemorrhage presumably due to intracranial atherosclerotic disease (ICAD) identified by VWI and silent on lumen-based imaging modalities. A 66-year-old female presented with sudden onset headache and dysarthria. A head CT showed intracranial hemorrhage centered in the right basal ganglia. Further imaging by CT angiography, MR angiography and a conventional catheter angiogram were negative. MRI of the brain, including VWI, showed abnormal enhancement in the right middle cerebral artery vessel wall, suggesting intracranial atherosclerotic changes in a prestenotic vessel. As a potential noninvasive screening test, VWI could impact patients with ICAD and become part of a stroke risk stratification algorithm.