Page 40 - Handbook of Deep Learning in Biomedical Engineering Techniques and Applications
P. 40

28   Chapter 2 Deep convolutional neural network in medical image processing




                                    presented comprehensively. Lastly, in Sections 5 and 6, a critical
                                    discussion with several concluding remarks is presented.

                                    2. Medical image analysis

                                       Medical imaging, in general, provides visual knowledge about
                                    the internal of the human system. This helps the clinicians and
                                    medical professionals to give a better diagnostic result and effi-
                                    cient treatment to the patients. Medical imaging of the human
                                    system can be carried out by using different medical imaging mo-
                                    dalities. There are several imaging modalities available in the
                                    market to recognize the human organ, such as magnetic reso-
                                    nance imaging (MRI), endoscopy, computed tomography (CT),
                                    X-ray,  positron  emission  tomography   (PET),  ultrasound,
                                    narrow-band imaging, elastography, optical imaging, infrared
                                    thermography, and terahertz [10e12]. Table 2.1 gives a compara-
                                    tive study of these imaging modalities. These techniques have an
                                    important role in providing vital anatomical and functional infor-
                                    mation of the different parts of the human body. Medical imaging
                                    is of great support for the modern healthcare system. Fig. 2.3 pro-
                                    vides an idea about the different organs for which the individual
                                    modality can be used. There are various areas of medical imaging
                                    in which DL methods were implemented successfully. Fig. 2.4
                                    shows these areas of application. A brief description of the various
                                    domains of clinical image analysis is stated in the following.


                                    2.1 Segmentation
                                       Segmentation is a process in which the image is divided into
                                    several nonoverlapping areas by taking a set of rules, which can
                                    be a set of features such as color, texture, and contrast or set of
                                    similar pixels [13]. This method helps to reduce the search region
                                    in an image by separating it into two groups such as the back-
                                    ground and the object. An important feature of segmentation is
                                    to represent the image in a form that is more meaningful and
                                    can be easily analyzed. This helps to extract several significant in-
                                    formation such as shape, position, volume, and different abnor-
                                    malities related to the organ [14,15]. Authors in Ref. [16] have
                                    presented a 3D clinical image segmentation approach in which
                                    the system has the ability to evaluate and compare the quality
                                    of segmentation. Feng et al. [17] have proposed a 3D multiscale
                                    Otsu thresholding algorithm, which is iterative in nature, for the
                                    segmentation of medical images. In this algorithm, the image is
                                    represented in multiple levels so as to remove the effect of weak
   35   36   37   38   39   40   41   42   43   44   45