Development of a method for the quantification of intramuscular connective tissue with ultrasound B-mode

Abstract

The aim of the present work is to develop a method for the quantification of intra-muscular connective tissue using diagnostic ultrasound. For this purpose, the effect of adjusting the ultrasound beam angle to the pennation angle of the fascicle structure in the muscle was investigated. Therefore, human and bovine muscles were scanned in two different planes, fascicle-aligned plane and fascicle-orthogonal plane, with varying insonation angles. Also, a method was derived to estimate intra-muscular connective tissue content of the scanned bovine muscles in order to compare it to the analysis parameters. The ultrasound images in fascicle-aligned plane were analysed with 2D-Fourier transformation and the ultrasound images in fascicle-orthogonal plane were analysed with second order statistic in form of a Grey Level Co-occurrence Matrix. The results showed that adjustment of the insonation angle improved the imaging of the intramuscular connective tissue in both scan planes. This provides a valuable basis for quantifying intra-muscular connective tissue in general. Additionally, one parameter, which is calculated on the basis of the frequency spectrum of the US images and describes the quality of imaging the fascicle structure, indicated correlation to intra-muscular connective tissue content. It is therefore suggested as a quantitative measure for intra-muscular connective tissue content due to its intrinsic nature.