Background

Hypertension affects cerebrovascular regulation.

Purpose

To show that cerebral blood flow is altered in hypertensive subjects exposed to dynamic maneuvers: head down tilt (HD).

Study type

Prospective. Population: 36 subjects (18 normotensive subjects (NT); 53,2 ± 8,8 years/18 Hypertensive subjects (HT); 53,7 ± 8,5 years). Field Strength/Sequence: 1.5 T/ASL in supine position and after 4 minutes of HD position. DWI/T2*/3D-TOF/FLAIR.

Assessment

Regions of interest from reconstructed cerebral blood-flow (CBF) maps: sub-cortical nuclear grey matter (Accumbens, amygdala, caudate, hippocampus, pallidum, putamen, thalamus), cortical gray matter (cGM) and white matter (WM). Hemodynamics parameters were monitored. Statistical tests Shapiro and Wilk, Fisher test, univariate and multivariate simple linear regression, Pearson correlation, Student's t-test.

Results

There was no significant CBF difference between NT and HT group in supine position. After head down tilt, the mean CBF across all structures fell by 5.8% on average in whole study group (n = 36) with a decrease of 6.6% and 7.6% respectively in white and gray matter (p < 0.001). The largest decreases were observed in Accumbens nuclei (9.6% left sided and 9.2% right sided (p < 0.001)). In HT patients, no difference (0/16) in CBF was found after HD, whereas CBF changed significantly in four (4/16) structures in NT (right and left accumbens, putamen and left caudate nucleus as well as in the gray substance). HT had less CBF variation in left caudate nuclei (p = 0.039) and cortical gray matter (cGM) (p = 0.013). Among HT group, patients with diabetes had a slightest change in CBF (mV_CBF) than the HT subjects only (Accumbens L (p = 0.031), Putamen R (p = 0.047), white matter (WM) (p = 0.015) and gray matter cortical (cGM) (p = 0.015)).

Data

.

Conclusion

Our study highlights the significant different reaction of CBF to head position between NT and HT subjects. This supports the hypothesis that hypertension is responsible for a deficient cerebral regulation.

中文翻译：

---

动脉高压对脑血流动力学的影响：头向下位置对健康和高血压受试者脑血流（asl–mri）的影响

背景

高血压会影响脑血管调节。

目的

要显示在动态操作的高血压受试者中脑血流量发生了变化：头向下倾斜（HD）。

研究类型

预期。人口：36名受试者（18名正常血压受试者（NT）； 53.2±8.8岁/ 18名高血压受试者（HT）； 53.7±8.5岁）。场强/顺序：仰卧位1.5升/ ASL，HD位置4分钟后。DWI / T2 * / 3D-TOF / FLAIR。

评定

重建的脑血流（CBF）图的感兴趣区域：皮层下核灰质（Accumbens，杏仁核，尾状，海马，苍白质，壳状核，丘脑），皮层灰质（cGM）和白质（WM）。监测血流动力学参数。统计检验Shapiro和Wilk，Fisher检验，单变量和多元简单线性回归，Pearson相关性，Student's t检验。

结果

仰卧位NT组与HT组之间无明显的CBF差异。头向下倾斜后，整个研究组中所有结构的平均CBF平均下降5.8％（n  = 36），白质和灰质分别下降6.6％和7.6％（p  <0.001）。下降最大的是Accumbens核（左侧为9.6％，右侧为9.2％（p  <0.001））。在HT患者中，HD后CBF无差异（0/16），而NT（右，左伏，壳核和左尾状核以及灰色物质）的四（4/16）个结构的CBF发生了显着变化）。HT在左尾状核（p  = 0.039）和皮质灰质（cGM）（p = 0.013）。在HT组中，糖尿病患者的CBF（mV_CBF）仅比HT受试者（Accumbens L（p  = 0.031），Putamen R（p  = 0.047），白质（WM）（p  = 0.015）和灰色的变化最小。皮层物质（cGM）（p  = 0.015）。

数据

。

结论

我们的研究突出了NT和HT受试者之间CBF对头部位置的显着不同反应。这支持了高血压导致大脑调节不足的假说。