Background and Purpose-Cerebral small-vessel disease and cerebral blood flow (CBF) are interrelated. However, the direction of the relationship is unknown, and longitudinal studies are scarce. We investigated the longitudinal relationship between CBF and white matter hyperintensities (WMHs) and lacunes, as representatives of cerebral small-vessel disease, in patients with manifest arterial disease. Methods-Within the Second Manifestations of Arterial Disease-Magnetic Resonance (SMART-MR) study, 1.5T brain magnetic resonance imaging, including an MR angiography, was obtained at baseline and after on ≈3.9 years of follow-up in 575 patients with manifest arterial disease (mean age, 57±10 years). Longitudinal associations of WMHs and lacunes with parenchymal CBF (pCBF; per 100-mL brain volume) were estimated using regression analyses, adjusted for age, sex, follow-up time, and baseline brain measures. Results-Baseline pCBF was not associated with progression of WMHs and lacunes over time. However, periventricular and deep WMHs at baseline were associated with decline in pCBF; mean (95% confidence interval) decline in pCBF per % intracranial volume increase in periventricular and deep WMH volume was −0.70 (−1.40 to −0.00) and −1.01 (−1.64 to −0.38) mL/min per 100-mL brain volume, respectively. These associations were partly explained by cardiovascular risk factors but remained significant for deep WMHs (mean decline [95% confidence interval] in pCBF per % intracranial volume increase in deep WMH volume was −0.92 [−1.56 to −0.28] mL/min per 100-mL brain volume). Lacunes were not associated with change in pCBF. Conclusions-In patients with manifest arterial disease, baseline periventricular and deep WMH volumes were associated with decline in pCBF over time, but baseline pCBF was not associated with progression of WMHs and lacunes over time. Of the 1309 patients included, 1152 patients had adequate brain segmentation and 2-dimensional (2D) MR angiography measurements. Of these 1152 patients, 1076 were still alive at follow-up and 674 participated. Of these, 575 patients had an MRI at baseline and follow-up, and adequate brain segmentation and 2D MR angiography measurements.The SMART-MR study was approved by the ethics committee of our institution and written informed consent was obtained from all patients.
MRI Protocol and Brain SegmentationAt baseline and follow-up, MR investigations were performed on a 1.5T whole-body system (Gyroscan ACS-NT; Philips Medical Systems, Best, the Netherlands). The protocol consisted of transversal T1-weighted (repetition time [TR]/echo time [TE], 235/2 ms), T2-weighted (TR/TE, 2200/11 and 2200/100 ms), fast fluid-attenuated inversion recovery (TR/TE/inversion time, 6000/100/2000 ms), and inversion recovery (TR/TE/inversion time, 2900/22/410 ms) sequences. Field of view was 230×230 mm (matrix size, 180×256; slice thickness, 4.0 mm; no gap; 38 slices).
11On the basis of a localizer MR angiographic slab in the sagittal plane, we positioned a 2D phase-contrast section at the level of the ...