Biomechanical properties of the hypoxic and dying brain quantified by magnetic resonance elastography. (1st January 2020)

• Record Type: Journal Article
• Authors: Bertalan, Gergely; Klein, Charlotte; Schreyer, Stefanie; Steiner, Barbara; Kreft, Bernhard; Tzschätzsch, Heiko; de Schellenberger, Angela Ariza; Nieminen-Kelhä, Melina; Braun, Jürgen; Guo, Jing; Sack, Ingolf
• Is Part Of: Acta biomaterialia. Volume 101(2020)
• Page Start: 395
• Page End: 402
• Publication Date: 2020-01-01
• Subjects: In vivo brain stiffness -- Brain mechanical properties -- Magnetic resonance elastography -- Brain death -- Hypoxia -- Cytotoxic edema; MRI magnetic resonance imaging -- MRE Magnetic resonance elastography -- DWI diffusion weighted imaging -- ADC apparent diffusion coefficient -- MRS magnetic resonance spectroscopy -- HAI hypoxic-anoxic injury -- RA respiratory arrest -- CA cardiac arrest -- T2w T2-weighted -- PMI post mortem interval -- WB whole brain -- HIP hippocampus -- Ins myo-inositol -- GABA γ-aminobutyric acid -- Lac lactate -- BBB blood-brain barrier; Biomedical materials -- Periodicals; 610.28
• DOI: 10.1016/j.actbio.2019.11.011
• Languages: English
• ISSNs: 1742-7061

Abstract

Abstract: Respiratory arrest is a major life-threatening condition leading to cessation of vital functions and hypoxic-anoxic injury of the brain. The progressive structural tissue changes characterizing the dying brain biophysically are unknown. Here we use noninvasive magnetic resonance elastography to show that biomechanical tissue properties are highly sensitive to alterations in the brain in the critical period before death. Our findings demonstrate that brain stiffness increases after respiratory arrest even when cardiac function is still preserved. Within 5 min of cardiac arrest, cerebral stiffness further increases by up to 30%. This early mechanical signature of the dying brain can be explained by water accumulation and redistribution from extracellular spaces into cells. These processes, together, increase interstitial and intracellular pressure as revealed by magnetic resonance spectroscopy and diffusion-weighted imaging. Our data suggest that the fast response of cerebral stiffness to respiratory arrest enables the monitoring of life-threatening brain pathology using noninvasive in vivo imaging. Statement of significance: Hypoxia-anoxia is a life-threatening condition eventually leading to brain death. Therefore, monitoring vital brain functions in patients at risk is urgently required during emergency care or treatment of acute brain damage due to insufficient oxygen supply. In mouse model of hypoxia-anoxia, we have shown for the first time that biophysical tissue parameters such as brain stiffness changed markedly during the process of death. Graphical abstract: Image, graphical abstract