Real-time laser speckle contrast imaging for intraoperative neurovascular blood flow assessment: animal experimental study.

The use of various blood flow control methods in neurovascular interventions is crucial for reducing postoperative complications. Neurosurgeons worldwide use different methods, such as contact Dopplerography, intraoperative indocyanine videoangiography (ICG) video angiography, fluorescein angiography, flowmetry, intraoperative angiography, and direct angiography. However, there is no noninvasive method that can assess the presence of blood flow in the vessels of the brain without the introduction of fluorescent substances throughout the intervention.

Laser Speckle Contrast Imaging in Neurosurgery: A Systematic Review.

Background: Intraoperative study of blood flow in the brain vessels is among the most critical topics of modern neurosurgery. One of the promising methods for intraoperative monitoring of blood flow is laser speckle contrast imaging (LSCI). This systematic review aims to analyze the experience of using intraoperative LSCI in neurosurgical interventions.

Impairments of cerebral blood flow microcirculation in rats brought on by cardiac cessation and respiratory arrest.

The impairments of cerebral blood flow microcirculation brought on by cardiac and respiratory arrest were assessed with multi-modal diagnostic facilities, utilising laser speckle contrast imaging, fluorescence spectroscopy and diffuse reflectance spectroscopy. The results of laser speckle contrast imaging show a notable reduction of cerebral blood flow in small and medium size vessels during a few minutes of respiratory arrest, while the same effect was observed in large sinuses and their branches during the circulatory cessation. Concurrently, the redox ratio assessed with fluorescence spectroscopy indicates progressing hypoxia, NADH accumulation and increase of FAD consumption.

Adrenaline induces calcium signal in astrocytes and vasoconstriction via activation of monoamine oxidase.

Adrenaline or epinephrine is a hormone playing an important role in physiology. It is produced de-novo in the brain in very small amounts compared to other catecholamines, including noradrenaline. Although the effects of adrenaline on neurons have been extensively studied, much less is known about the action of this hormone on astrocytes.