Quantification and Performance Analysis of Thyroid Nodule Features from Ultrasound Images

The ultrasound technology is widely used in diagnosis of the thyroid nodules. Currently, evaluation of nodule features on the ultrasound images is subjectively made by the medical examiners. There are two major shortcomings of the present approach. First, the result of evaluation varies under different medical examiners. Second, due to the naked-eye evaluation, the evaluation result is usually categorical and is incapable of showing the gravity level of the observed feature.n the literature, the major features for diagnosis of thyroid nodules are microcalcification, hypoechoic lesion, heterogeneous echo texture and margin blur on gray-scale images. In power Doppler images, the major feature is the observation on the volume blood flow of the peripheral area around the nodule. In this research, we attempt to quantify these features on the images. The diagnosis power is compared between the quantitative features and the conventional qualitative features. Furthermore, the Fisher Linear Discrminant is employed on these quantitative features to obtain a linear combination for a better classification power. To validate the proposed approach, we use the data sample provided by National Taiwan University Hospital(NTUH) to retrieve the quantitative features, The clinical data also provided by NTUH, is then used to evaluate the diagnosis accuracy.