Recent Advances in Fluorescence Imaging of Traumatic Brain Injury in Animal Models.

Fei Lu,Wenjuan Zhou,Qinglun Su,Huihai Wang,Jiating Cao,Weijiang Guan,Qin Zhao

doi:10.3389/fmolb.2021.660993

Abstract

Traumatic brain injury (TBI) is one of the top three specific neurological disorders, requiring reliable, rapid, and sensitive imaging of brain vessels, tissues, and cells for effective diagnosis and treatment. Although the use of medical imaging such as computed tomography (CT) and magnetic resonance imaging (MRI) for the TBI detection is well established, the exploration of novel TBI imaging techniques is of great interest. In this review, recent advances in fluorescence imaging for the diagnosis and evaluation of TBI are summarized and discussed in three sections: imaging of cerebral vessels, imaging of brain tissues and cells, and imaging of TBI-related biomarkers. Design strategies for probes and labels used in TBI fluorescence imaging are also described in detail to inspire broader applications. Moreover, the multimodal TBI imaging platforms combining MRI and fluorescence imaging are also briefly introduced. It is hoped that this review will promote more studies on TBI fluorescence imaging, and enable its use for clinical diagnosis as early as possible, helping TBI patients get better treatment and rehabilitation.

Highlights

Traumatic brain injury (TBI) refers to a brain damage caused by trauma, usually occurring in traffic accidents, falls, violent blows, sports, and combat (Leeds et al, 2014; Treble-Barna et al, 2017; Li et al, 2018)
Various fluorescence imaging techniques for TBI diagnosis have made considerable progress due to their abilities to directly detect and visualize brain microstructures and to track dynamic changes during TBI injury, treatment, and rehabilitation. It overcomes the deficiency of strong radiation, low resolution and low sensitivity of conventional brain magnetic resonance imaging (MRI) and computed tomography (CT), showing great clinic potentials in the diagnosis and treatment of TBI
The appearance of organic fluorophores with large photon absorption cross sections and high fluorescence quantum efficiency has greatly promoted the development of twophoton or even three-photon imaging for TBI diagnosis

Summary

INTRODUCTION

Traumatic brain injury (TBI) refers to a brain damage caused by trauma, usually occurring in traffic accidents, falls, violent blows, sports, and combat (Leeds et al, 2014; Treble-Barna et al, 2017; Li et al, 2018). As one of the top three specific neurological disorders worldwide, TBI has become a huge public problem that threatens human health and life. During the TBI process, the initial impact causes both primary and secondary injuries. Some pathophysiological processes, such as post-traumatic neurotransmitter release, free radical generation, mitochondrial dysfunction, inflammatory response, abnormal coagulation function, and blood−brain barrier damage, subsequently cause secondary brain injuries and lead to cerebrovascular and neurological disorders (Brown et al, 2019; Glotfelty et al, 2019; Ghosh et al, 2020). Rapid and sensitive imaging of brain tissues, cerebrovascular vessels, and cells is important for the diagnosis and treatment of TBI

Fluorescence Imaging of TBI

IMAGING OF CEREBRAL VESSELS

IMAGING OF BRAIN CELLS AND TISSUES

IMAGING OF BIOMARKERS

MULTIMODAL IMAGING

CONCLUSION AND OUTLOOK