Department of Radiology, UMCU Brain Center, University Medical Center Utrecht, Utrecht, The Netherlands.
Department of Cardiology, Amsterdam Medical Center Location Vu, Amsterdam, The Netherlands.
J Magn Reson Imaging. 2022 Jun;55(6):1785-1794. doi: 10.1002/jmri.27989. Epub 2021 Nov 18.
Damping of heartbeat-induced pressure pulsations occurs in large arteries such as the aorta and extends to the small arteries and microcirculation. Since recently, 7 T MRI enables investigation of damping in the small cerebral arteries.
To investigate flow pulsatility damping between the first segment of the middle cerebral artery (M1) and the small perforating arteries using magnetic resonance imaging.
Retrospective.
Thirty-eight participants (45% female) aged above 50 without history of heart failure, carotid occlusive disease, or cognitive impairment.
FIELD STRENGTH/SEQUENCE: 3 T gradient echo (GE) T1-weighted images, spin-echo fluid-attenuated inversion recovery images, GE two-dimensional (2D) phase-contrast, and GE cine steady-state free precession images were acquired. At 7 T, T1-weighted images, GE quantitative-flow, and GE 2D phase-contrast images were acquired.
Velocity pulsatilities of the M1 and perforating arteries in the basal ganglia (BG) and semi-oval center (CSO) were measured. We used the damping index between the M1 and perforating arteries as a damping indicator (velocity pulsatility /velocity pulsatility ). Left ventricular stroke volume (LVSV), mean arterial pressure (MAP), pulse pressure (PP), and aortic pulse wave velocity (PWV) were correlated with velocity pulsatility in the M1 and in perforating arteries, and with the damping index of the CSO and BG.
Correlations of LVSV, MAP, PP, and PWV with velocity pulsatility in the M1 and small perforating arteries, and correlations with the damping indices were evaluated with linear regression analyses.
PP and PWV were significantly positively correlated to M1 velocity pulsatility. PWV was significantly negatively correlated to CSO velocity pulsatility, and PP was unrelated to CSO velocity pulsatility (P = 0.28). PP and PWV were uncorrelated to BG velocity pulsatility (P = 0.25; P = 0.68). PWV and PP were significantly positively correlated with the CSO damping index.
Our study demonstrated a dynamic damping of velocity pulsatility between the M1 and small cerebral perforating arteries in relation to proximal stress.
4 TECHNICAL EFFICACY: Stage 1.
心跳引起的压力脉动在主动脉等大动脉中被阻尼，并扩展到小动脉和微循环。最近，7T MRI 可以研究小脑中动脉的阻尼。
使用磁共振成像研究大脑中动脉第一段（M1）和小穿支动脉之间的血流搏动阻尼。
回顾性。
38 名受试者（45%为女性）年龄大于 50 岁，无心力衰竭、颈动脉闭塞性疾病或认知障碍史。
磁场强度/序列：3T 梯度回波（GE）T1 加权图像、自旋回波液体衰减反转恢复图像、GE 二维（2D）相位对比和 GE 电影稳态自由进动图像。在 7T 时，采集 T1 加权图像、GE 定量流量和 GE 2D 相位对比图像。
测量基底节（BG）和半卵圆中心（CSO）中 M1 和穿支动脉的速度脉动。我们使用 M1 和穿支动脉之间的阻尼指数作为阻尼指标（速度脉动/速度脉动）。左心室每搏量（LVSV）、平均动脉压（MAP）、脉压（PP）和主动脉脉搏波速度（PWV）与 M1 和穿支动脉的速度脉动以及 CSO 和 BG 的阻尼指数相关。
用线性回归分析评估 LVSV、MAP、PP 和 PWV 与 M1 和小穿支动脉速度脉动的相关性，以及与阻尼指数的相关性。
PP 和 PWV 与 M1 速度脉动呈显著正相关。PWV 与 CSO 速度脉动呈显著负相关，而 PP 与 CSO 速度脉动无关（P=0.28）。PP 和 PWV 与 BG 速度脉动无关（P=0.25；P=0.68）。PWV 和 PP 与 CSO 阻尼指数呈显著正相关。
我们的研究表明，在近端压力的作用下，M1 与小脑中的动脉之间存在速度脉动的动态阻尼。
4 级 技术效果：1 级。
