Department of Biomedical Engineering, Linköping University, Linköping, Sweden.
Department of Neurosurgery and Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden.
Microcirculation. 2024 Nov;31(8):e12884. doi: 10.1111/micc.12884. Epub 2024 Sep 28.
Laser Doppler flowmetry (LDF) is a well-established technique for the investigation of tissue microcirculation. Compared to skin, the use in the human brain is sparse. The measurement of cerebral microcirculation in neurointensive care and during neurosurgery is challenging and requires adaptation to the respective clinical setting. The aim of the review is to present state of the art and progress in neurosurgery and neurointensive care where LDF has proven useful and can find clinical importance in the investigation of cerebral microcirculation. The literature in the field is summarized and recent technical improvements regarding LDF systems and fiber optical probe designs for neurosurgical and neurocritical care described. By combining two signals from the LDF unit, the measurement of the microcirculation (Perfusion) and gray whiteness (TLI) of the brain tissue, the full potential of the device is achieved. For example, a forward-looking LDF-probe detects high-risk hemorrhage areas and gray-white matter boundaries along intraoperative trajectories during stereotactic neurosurgery. Proof of principles are given for LDF as a guidance tool in deep brain stimulation implantation, brain tumor needle biopsies, and as long-term monitoring device in neurocritical care. With well-designed fiber optical probes, surgical fixation, and signal processing for movement reduction, LDF monitoring of the cerebral microcirculation is successful up to 10 days. The use of LDF can be combined with other physiological measurement techniques, for example, fluorescence spectroscopy for identification of glioblastoma during tumor surgery. Fiber optics can also be used during magnetic resonance imaging (MRI). Despite the many advantages, fiber optical LDF has not yet reached its full potential in clinical neuro-applications. Multicenter studies are required to further evaluate LDF in neurosurgery and neurointensive care. In conclusion, the present status of LDF in neurosurgery and neurointensive care has been reviewed. By combining Perfusion and TLI with tailored probe designs the full potential of LDF can be achived in measuring cerebral microcirculation. This includes guidance during DBS implantation and needle biopsies, and long-term monitoring in neurocritical care.
激光多普勒流量测定（LDF）是一种成熟的组织微循环研究技术。与皮肤相比，其在人脑中的应用较为稀少。在神经重症监护和神经外科手术中测量脑微循环具有挑战性，需要适应各自的临床环境。本综述的目的是介绍 LDF 在神经外科和神经重症监护中的应用现状和进展，以及在脑微循环研究中具有临床意义的技术进步。总结了该领域的文献，并描述了 LDF 系统和光纤探头设计的最新技术改进，用于神经外科和神经重症监护。通过结合 LDF 单元的两个信号，即组织的微循环（灌注）和灰白质（TLI）测量，可以实现设备的全部潜能。例如，前瞻性 LDF 探头可在立体定向神经外科手术期间沿手术轨迹检测高危出血区域和灰白质边界。为 LDF 作为深部脑刺激植入、脑肿瘤针吸活检以及神经重症监护中长期监测装置的指导工具提供了原理证明。通过设计良好的光纤探头、手术固定和减少运动的信号处理，可以成功监测长达 10 天的脑微循环。LDF 的使用可以与其他生理测量技术相结合，例如在肿瘤手术期间识别胶质母细胞瘤的荧光光谱。光纤也可用于磁共振成像（MRI）。尽管具有许多优势，但光纤 LDF 在临床神经应用中尚未充分发挥其潜力。需要进行多中心研究，以进一步评估 LDF 在神经外科和神经重症监护中的应用。总之，本文综述了 LDF 在神经外科和神经重症监护中的现状。通过将灌注和 TLI 与定制的探头设计相结合，可以充分发挥 LDF 在测量脑微循环方面的潜力。这包括在 DBS 植入和针吸活检期间的指导以及神经重症监护中的长期监测。
