Automatic Prostate Segmentation in Ultrasound Images Using GVF Active Contour

Prostate cancer is one of the leading causes of death by cancer among men in the world. Ultrasonography is said to be the safest technique in medical imaging so it is used extensively in prostate cancer detection. In the other hand determining of prostate’s boundary in TRUS (Transrectal Ultrasound) images is very necessary in lots of treatment methods prostate cancer. So first and essential step for computer aided diagnosis (CAD) is the automatic prostate segmentation that is an open problem still. But the low SNR, presence of strong speckle noise, Weakness edges and shadow artifacts in these kind of images limit the effectiveness of classical segmentation schemes. The classical segmentation methods fail completely or require post processing step to remove invalid object boundaries in the segmentation results. This paper has proposed a fully automatic algorithm for prostate segmentation in TRUS images that overcomes the explained problems completely. The presented algorithm contains three main stages. First morphological smoothing and sticks filter are used for noise removing. A neural network is employed in second step to find a point in prostate region. Finally in the last step, the prostate boundaries is extracted by GVF active contour. Some experiments for the performance validity of the presented method, compare the extracted prostate by the proposed algorithm with manually-delineated boundaries by radiologist. The results show that our method extracts prostate boundaries with mean square area error lower than 4.4%.