Akiyoshi Yamamoto RT, Presenter: Nothing to Disclose

Katsumi Nakamura MD, Abstract Co-Author: Nothing to Disclose

Kiyomi Kuroki RT, Abstract Co-Author: Nothing to Disclose

Riichiro Nagashima RT, Abstract Co-Author: Nothing to Disclose

Mitsue Miyazaki PhD, Abstract Co-Author: Employee, Toshiba Corporation

To evaluate the feasibility of a non-contrast time resolved MR angiography (MRA) technique using ECG-gated two-dimensional half-Fourier FSE by measuring an arterial pulse wave velocity (PWV), which is thought as an indicator of the arterial stiffness.

All MR examinations were performed using a Toshiba EXCELART 1.5T with a torso SPEEDER coil. The 2D single-shot images in multiple cardiac phases using a 5 or 10 msec interval were acquired in the coronal plane with ECG-triggered half-Fourier FSE, TR of 3- or 4RR interval, ETS of 4 ms, TEeff of 32 ms, matrix of 192x256, and a 70-mm thick slice. Signal change at two points in the lower extremity artery was measured using an ROI analysis from the time-signal intensity curve. The PWV was calculated using PWV=D/T; where T is a transit time of the signal decrease point in the signal intensity curve and D is a distance between the two ROIs manually measured on the computer screen. Twenty-five subjects include 6 normal volunteer (mean age; 27.6 y.o.), 11 patients without symptoms or past history of cardiovascular diseases (mean age; 74.1 y.o.), and 6 patients with arteriosclerosis obliterans (ASO) (mean age; 71.5 y.o.). We evaluated that 1) the relationship of PWV and age, 2) alternation of PWV in patients with atherosclerosis, and 3) the correlation between PWV and brachial - ankle PWV (baPWV). The baPWV was measured using a volume-plethymographic apparatus.

The PWV increases linearly with ages in the normal subjects (r=0.64). The PWV of the ASO patients was significantly higher than that of healthy subjects (13.6±5.4 m/sec, 8.0±2.3 m/sec, respectively; p<0.05). A well-correlated phenomenon is observed between the two measurements (r=0.58, p<0.01). Our method allows observation of the regional change of PWV.

The technique can be incorporated in the routine clinical study of MRA; therefore, it becomes possible to evaluate functional changes of arterial wall using PWV and morphology using non-contrast MRA.

A non-contrast time resolved MR angiography technique using ECG-gated two-dimensional half-Fourier FSE allows evaluation of the change in arterial wall stiffness as well as flow dynamics.

Yamamoto, A, Nakamura, K, Kuroki, K, Nagashima, R, Miyazaki, M, The Feasibility of the Assessment of Arterial Wall Stiffness Using a Pulse Wave Velocity (PWV) Measured with a Non-contrast Time Resolved MRA Technique Using ECG-gated Two-dimensional Half-Fourier FSE.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5012682.html