Ingolf Sack1, Bernd Beierbach1, Jens Wuerfel2, Uwe Hamhaber3, Dieter Klatt1, Sebastian Papazoglou1, Peter Martus4, Braun Juergen3
1Department of Radiology, Charit - University Medicine Berlin, Berlin, Germany; 2Department of Neuroradiology, University Lbeck, Lbeck, Schleswig-Holstein, Germany; 3Institute of Medical Informatics, Charit - University Medicine Berlin, Berlin, Germany; 4Institute of Biometry and Epidemiology, Charit - University Medicine Berlin, Berlin, Germany
Multifrequency magnetic resonance elastography was used to investigate the in vivo viscoelasticity of healthy human brain in 55 volunteers ranging in age from 18 to 88 years. The application of four vibration frequencies in an acoustic range from 25 to 62.5 Hz revealed for the first time how physiological aging changes the global viscoelasticity of the brain. It is shown that the healthy adult brain undergoes steady parenchymal liquefaction characterized by a continuous decline in viscoelasticity (0.8% per year, P<0.001). Furthermore, significant sex differences were found with female brains being on average 9% more viscoelastic than their male counterparts (P=0.016).