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Bioinformatics of the Brain

brain. Tumor detection studies are focused on determining the exact location,

size, shape, and type (benign or malignant) of the tumor in the brain [1].

Due to the intricate nature of the brain, the identification of brain tumors

through MRI is challenging. Even a qualified radiologist can come to erro-

neous conclusions in the tumor grading. Image segmentation plays a vital role

in medical image processing as it enables the extraction of necessary features

for anomaly detection in the scanned image. The analysis of the images with

precise image processing techniques is essential for professionals to compre-

hend the images within a short duration and make rapid decisions. Image

processing techniques included in clinical decision support systems will help

to increase the diagnostic efficiency of physicians and reduce the possibility of

misdiagnosis [1]. The favorable outcomes to be obtained in these systems are

important in terms of determining the most appropriate treatment for brain

tumors. Given the aforementioned reasons, it appears imperative to imple-

ment automated segmentation techniques for MRI images. The objective of

this section in the book is to present a thorough examination of the diverse

image-processing approaches employed in the segmentation of brain tumors.

4.2

Magnetic Resonance Imaging (MRI)

MRI is one of the commonly used methods to obtain anatomical information

from the brain. MRI provides visualization of general morphological features of

brain tissues. It is used to detect physical abnormalities, lesions, and damages

in the brain.

During the acquisition of an MRI image, the patient is first placed in a

large tunnel-shaped device that has a large magnet and a strong magnetic

field. The protons in the patient’s body are stimulated with radio frequency

waves. Protons that receive energy deviate from their positions according to

the amount of energy they receive. When the radio frequency energy is cut

off, the protons return to their previous positions and emit the energy they

received as a signal. MRI images are created using these signals [2].

An MRI procedure poses no risk of radiation exposure as it does not uti-

lize ionizing radiation. Nevertheless, the utilization of a powerful magnet in

MRI renders it infeasible to acquire images from patients with pacemakers,

aneurysm clips, cochlear implants, or vascular stents [3].

4.2.1

Axial, Coronal, and Sagittal Plane

The locations of structures in the human anatomy are described using hypo-

thetical planes called anatomical planes. During brain imaging, the brain is

displayed as two-dimensional (2D) slices. The three planes most commonly

used to describe the locations of structures in the brain anatomy are shown in