2012 Proceedings - International Tissue Elasticity Conference

Session MPT–2: Mechanical Properties of Tissues – II
Thursday, October 4 5:00P – 6:00P
014 CEREBRAL TISSUE MOTION AND LEUKO–ARAIOSIS IN THE ELDERLY: A CORRELATION
STUDY USING ULTRASOUND AND MAGNETIC RESONANCE IMAGING.
R. Ternifi 1 , X. Cazals 1 , A. Lorette 1 , T. Desmidt 1 , V. Camus 1 , J.P. Cottier 1 , F. Patat 2 and J.P. Remenieras 1 .
1 Université François Rabelais, UMRS INSERM U930, 10 bd Tonnellé, 37032 Tours, FRANCE;
2 CIC–IT 806, CHRU de Tours, Tours, FRANCE.
Background: Leuko–araiosis (LA) is the term describing lesions and rarefaction of the cerebral White
Matter (WM) and is frequently seen in aged individuals. Although the mechanism of LA remains
unknown, a decrease in cerebral perfusion is suspected to be linked to LA. Many patients can have LA
without associated any clinical abnormality, however, new findings suggest that LA may be clinically
important [1,2]. Patients with LA have a decreased prognosis in terms of death, stroke and myocardial
infarction occurrences.
Aims: The aim of our work was to study the relationship between LA and the natural brain tissue velocity
due to pulsed cerebral perfusion. Brain velocities were measured with an analog of the Tissue Pulsatility
Imaging (TPI) method described by Kucewicz [3], which already been used by our group for depressed
patients [4].
Methods: Nine healthy female volunteers between the ages of 60 and 85 were enrolled in this
cross–sectional study. Transcranial acquisitions were performed with a 2MHz phased–array probe
through the right temporal bone window, and off–line estimations of velocity were performed by 1D
correlation methods on the radiofrequency (RF) lines of the collected 2D data. Velocity signals were then
filtered around the cardiac frequency to remove the respiratory component. MRI examinations were
performed on a 1.5T GE system using dedicated software (MRIcro) to obtain a volumetric analysis. The
primary endpoints of the study were the maximum brain velocity (TPImax), the absolute MRI volume of
WM hypersignals (VAbs) and the relative volume of the right hemisphere (VRel). The Pearson correlation
coefficient was used for statistics.
Results: Our main finding is that TPImax decreases significantly when the severity of LA increases, see
Figure 1. Significant inverse correlation between TPImax and VRel (ρ=-0.81, p