Background: While type 2 diabetes (T2D) is a major risk for ischemic stroke, the associated vessel wall characteristics remain essentially unknown. This study aimed to clarify intracranial vascular changes on three-dimensional vessel wall imaging (3D-VWI) using fast spin echo by employing 7Tesla (7T) magnetic resonance imaging (MRI) in T2D patients without advanced atherosclerosis as compared to healthy controls. Methods: In 48 T2D patients and 35 healthy controls, the prevalence of cerebral small vessel diseases and intracranial plaques were evaluated by 3D-VWI with 7T MRI. Results: The prevalence rate of lacunar infarction was significantly higher in T2D than in controls (n = 8 in T2D vs. n = 0 in control, p = 0.011). The mean number of intracranial plaques in both anterior and posterior circulation of each subject was significantly larger in T2D than in controls (2.23 in T2D vs. 0.94 in control, p < 0.01). In T2D patients, gender was associated with the presence of intracranial plaques. Conclusion: This is the first study to demonstrate the high prevalence of intracranial plaque in T2D patients with neither confirmed atherosclerotic disease nor symptoms by performing intracranial 3D-VWI employing 7TMRI. Investigation of intracranial VWI with 7T MRI is expected to provide novel insights allowing early intensive risk management for prevention of ischemic stroke in T2D patients.

Quantitative susceptibility mapping (QSM) has been proposed to assess intraplaque hemorrhage (IPH) in the carotid artery. The purpose of this study was to compare the diagnostic accuracy of preoperative QSM with that of the conventional T1-weighed (T1W) three-dimensional (3D)-FSE sequence for detecting IPH in cervical ICA stenosis in patients undergoing carotid endarterectomy (CEA) using histology as the reference standard. Carotid T1W 3D-FSE and QSM images were obtained from 16 patients with cervical ICA stenosis before CEA. Relative signal intensity (RSI) and susceptibility of the ICA were measured on three axial images including the location of most severe stenosis on T1W 3D-FSE and QSM images, respectively. Three transverse sections of carotid plaques excised by CEA, which corresponded with images on MRI, were stained with H&E, antibody against glycophorin A and Prussian blue, and the relative area (RA) of histologic IPH was calculated. The correlation coefficient was significantly greater between susceptibility and RA-histologic IPH (ρ = 0.691) than between RSI and RA-histologic IPH (ρ = 0.413; P = .0259). The areas under the receiver operating characteristic curves for detecting histologic sections consisting primarily of IPH (RA-histologic IPH > 40.7%) tended to be greater for susceptibility (0.964) than for T1WI FSE-RSI (0.811). Marginal homogeneity was observed between susceptibility and histologic sections consisting primarily of IPH (P = .0412) but not between T1W FSE-RSI and histologic sections consisting primarily of IPH (P = .1824). Pre-CEA QSM detects histologic IPH in cervical ICA stenosis more accurately than preoperative T1W 3D-FSE imaging. QSM = quantitative susceptibility mapping; IPH = intraplaque hemorrhage; T1W = T1-weighed; 3D = three-dimensional; CEA = carotid endarterectomy; RSI = relative signal intensity; RA = relative area.