Background

Bipolar Disorder (BD) is a severe chronic psychiatric disorder whose aetiology is still largely unknown. However, increasing literature reported the involvement of neurovascular factors in the pathophysiology of BD, suggesting that a measure of Cerebral Blood Flow (CBF) could be an important biomarker of the illness. To date, Magnetic Resonance Perfusion Weighted Imaging (PWI) techniques, such as Dynamic Susceptibility Contrast (DSC) and Arterial Spin Labelling (ASL), allow non-invasive in-vivo perfusion measurements. In this context, this review aims to summarize the results from all PWI studies that evaluated the CBF in BD.

Methods

A bibliographic search in PubMed up until May 2021 was performed. 16 PWI studies that used DSC or ASL sequences met our inclusion criteria.

Results

Overall, the results supported the presence of hyper-perfusion in the cingulate cortex and fronto-temporal regions, and the presence of hypo-perfusion in the cerebellum in BD, compared with both healthy controls and patients with unipolar depression. CBF changes after cognitive and aerobic training, as well as in relation with other physiological, clinical, and neurocognitive variables were also reported.

Limitations

The heterogeneity across the studies in terms of experimental designs, sample selection, and methodological approach employed limited the studies' comparison.

Conclusions

These findings showed CBF alterations in the cingulate cortex, fronto-temporal regions, and cerebellum in BD, suggesting that CBF may be an important pathophysiological marker of BD that merits further investigation to clarify the extent of neurovascular alterations.

中文翻译：

---

双相情感障碍的神经血管改变：灌注加权磁共振成像研究综述

背景

双相情感障碍（BD）是一种严重的慢性精神疾病，其病因仍然很大程度上未知。然而，越来越多的文献报道神经血管因素参与 BD 的病理生理学，这表明脑血流量 (CBF) 的测量可能是该疾病的重要生物标志物。迄今为止，磁共振灌注加权成像 (PWI) 技术，如动态磁化率对比 (DSC) 和动脉自旋标记 (ASL)，允许进行无创的体内灌注测量。在这种情况下，本综述旨在总结评估 BD 中 CBF 的所有 PWI 研究的结果。

方法

在 PubMed 中进行了截至 2021 年 5 月的书目检索。16 项使用 DSC 或 ASL 序列的 PWI 研究符合我们的纳入标准。

结果

总体而言，与健康对照组和单相抑郁症患者相比，结果支持在 BD 中扣带皮层和额颞区存在高灌注，以及在小脑中存在低灌注。还报告了认知和有氧训练后以及与其他生理、临床和神经认知变量相关的 CBF 变化。

限制

在实验设计、样本选择和所采用的方法学方法方面，研究的异质性限制了研究的比较。

结论

这些发现显示 BD 中扣带皮层、额颞区和小脑的 CBF 改变，表明 CBF 可能是 BD 的重要病理生理标志物，值得进一步研究以阐明神经血管改变的程度。