Integrating a learned probabilistic model with energy functional for ultrasound image segmentation

The segmentation of ultrasound (US) images is steadily growing in popularity, owing to the necessity of computer-aided diagnosis (CAD) systems and the advantages that this technique shows, such as safety and efficiency. The objective of this work is to separate the lesion from its background in US images. However, most US images contain poor quality, which is affected by the noise, ambiguous boundary, and heterogeneity. Moreover, the lesion region may be not salient amid the other normal tissues, which makes its segmentation a challenging problem. In this paper, an US image segmentation algorithm that combines the learned probabilistic model with energy functionals is proposed. Firstly, a learned probabilistic model based on the generalized linear model (GLM) reduces the false positives and increases the likelihood energy term of the lesion region. It yields a new probability projection that attracts the energy functional toward the desired region of interest. Then, boundary indicator and probability statistical–based energy functional are used to provide a reliable boundary for the lesion. Integrating probabilistic information into the energy functional framework can effectively overcome the impact of poor quality and further improve the accuracy of segmentation. To verify the performance of the proposed algorithm, 40 images are randomly selected in three databases for evaluation. The values of DICE coefficient, the Jaccard distance, root-mean-square error, and mean absolute error are 0.96, 0.91, 0.059, and 0.042, respectively. Besides, the initialization of the segmentation algorithm and the influence of noise are also analyzed. The experiment shows a significant improvement in performance. Graphical abstract A. Description of the proposed paper. B. The main steps involved in the proposed method.