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[[abstract]]DOI 10.1007/s10967-013-2564-

Purpose: To solve the problem of the basal descent movement in quantification of the regional left ventricular (LV) myocardial wall thickness (WTh) and wall thickening (%WT) in short-axis (SA) cine MRI for effectively assessing the regional wall motion of LV myocardium.Materials and Methods: LV long-axis tagged MRI and SA cine MRI were performed to calculate the longitudinal translation and circumferential WTh of LV myocardium in eight normal volunteers. The new SA end-systolic thickness (EST) data were reconstructed from the original EST data, based on the quantified longitudinal translation of LV myocardium. Results:The mean %WT of six segments in the basal section after correction was significantly different from that before correction in both intra-and inter-operator experiments. The polar map also showed the significant improvement of the variability of regional %WT and lack of quantification of %WT in the most basal SA slices after correction. Conclusion:The proposed technique demonstrated an important advantage to calculate the %WT in the most basal SA myocardial tissue, which was considered difficult to be achieved using cine MRI. THE SHORT-AXIS (SA) cardiac imaging method has been routinely performed for qualitative or quantitative evaluation of regional left ventricular (LV) function (1-4), however, two potential sources of error make it difficult to precisely measure the LV functional parameters. First, the cross-sectional planes of SA images not strictly perpendicular to the myocardial wall of the left ventricle, especially in the areas near the apex. This problem has been solved by implementing a three-dimensional (3D) approach to calculating wall thickness (WTh) perpendicular to the LV myocardial wall at the different cardiac phases (5). Usually the 3D elemental approach has been applied for detail measurement of the WTh toward the apex. Second, an important phenomenon in the dynamics of cardiac contraction is basal descent during systole. In SA cardiac imaging, the most basal image planes covering the upper part of the left ventricle at enddiastole (ED) do not show the upper part of the left ventricle at end-systole (ES), but rather part of the left atrium or valvular area. Generally, only the planes including the LV myocardium at ED and ES have been quantitatively analyzed, and those most basal SA slices not covering the left ventricle at ES have been excluded.In evaluating the LV volume parameters with cine MRI, Marcus et al found significant differences between the values with and without inclusion of the most basal slices and suggested using more SA images for complete LV coverage (6). In assessing the regional myocardial WTh and wall thickening (%WT), the problems of the basal-descent movement were more complicated because of the through-plane movement during systole. The myocardium at ES was not in the same position as at end-systole in the same imaging plane. This makes it impossible to measure the wall thickness of the exact portion of LV

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