Introducing kernel based morphology as an enhancement method for mass classification on mammography.

Since mammography images are in low-contrast, applying enhancement techniques as a pre-processing step are wisely recommended in the classification of the abnormal lesions into benign or malignant. A new kind of structural enhancement is proposed by morphological operator, which introduces an optimal Gaussian Kernel primitive, the kernel parameters are optimized the use of Genetic Algorithm. We also take the advantages of optical density (OD) images to promote the diagnosis rate. The proposed enhancement method is applied on both the gray level (GL) images and their OD values respectively, as a result morphological patterns get bolder on GL images; then, local binary patterns are extracted from this kind of images. Applying the enhancement method on OD images causes more differences between the values therefore a threshold method is applied toremove some background pixels. Those pixels that are more eligible to be mass are remained, and some statistical texture features are extracted from their equivalent GL images. Support vector machine is used for both approaches and the final decision is made by combining these two classifiers. The classification performance rate is evaluated by Az, under the receiver operating characteristic curve. The designed method yields Az = 0.9231, which demonstrates good results.

IMPST: A New Interactive Self-Training Approach to Segmentation Suspicious Lesions in Breast MRI.

Breast lesion segmentation in magnetic resonance (MR) images is one of the most important parts of clinical diagnostic tools. Pixel classification methods have been frequently used in image segmentation with two supervised and unsupervised approaches up to now. Supervised segmentation methods lead to high accuracy, but they need a large amount of labeled data, which is hard, expensive, and slow to be obtained. On the other hand, unsupervised segmentation methods need no prior knowledge and lead to low performance. However, semi-supervised learning which uses not only a few labeled data, but also a large amount of unlabeled data promises higher accuracy with less effort. In this paper, we propose a new interactive semi-supervised approach to segmentation of suspicious lesions in breast MRI. Using a suitable classifier in this approach has an important role in its performance; in this paper, we present a semi-supervised algorithm improved self-training (IMPST) which is an improved version of self-training method and increase segmentation accuracy. Experimental results show that performance of segmentation in this approach is higher than supervised and unsupervised methods such as K nearest neighbors, Bayesian, Support Vector Machine, and Fuzzy c-Means.