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Evaluating the Effectiveness of the Convolution Neural Network in Detecting Brain Tumors
Published in Rekh Ram Janghel, Rohit Raja, Korhan Cengiz, Hiral Raja, Next Generation Healthcare Systems Using Soft Computing Techniques, 2023
Tatwadarshi P. Nagarhalli, Sneha Mhatre, Ashwini Save, Sanket Patil
Like any other disease, early detection and diagnosis of brain tumor plays a vital role in providing care for the patients and thus saving lives. Of the different ways in which the brain tumor can be detected is magnetic resonance imaging (MRI) or computed tomography (CT). MRI is a form of scan that produces detailed pictures of the inside of the body using high magnetic fields and radio waves [12]. On the other hand, CT scan creates a 3D picture of soft tissues and bones using a sequence of X-rays and a computer. The output of both these techniques ia in the form of a series of images [13].
Magnetic Resonance Imaging
Published in Bethe A. Scalettar, James R. Abney, Cyan Cowap, Introductory Biomedical Imaging, 2022
Bethe A. Scalettar, James R. Abney, Cyan Cowap
MRI has many strengths. MRI is very safe, due to the use of low-energy RF radiation, and is capable of evaluating both anatomy and function. MRI can generate slices at any orientation and can generate contrast using parameters, such as signal decay times, that are much more tissue-specific than proton density. This latter capability is a source of exceptional soft tissue contrast, and thus MRI commonly is used to study abdominal organs and soft tissue (e.g., cartilage and ligament) damage and to identify tumors. One application in which MRI particularly excels relative to competing modalities, notably CT, is imaging both function and abnormalities of the brain. In these cases, the superior contrast detail of MRI makes abnormalities more visible. Limitations of MRI include the high cost of the equipment, generally slow image acquisition and an associated need for patients to remain motionless, and incompatibility with pacemakers and metal implants. Exposure to high levels of RF radiation also has the potential to induce patient heating.
Examples of linear inverse problems
Published in Mario Bertero, Patrizia Boccacci, Christine De Mol, Introduction to Inverse Problems in Imaging, 2021
Mario Bertero, Patrizia Boccacci, Christine De Mol
MRI is able to image both the anatomy and the physiological processes of the human body. In general, the strong magnetic field and the radio-frequency are tailored to match the intrinsic frequency of the magnetic moment of the hydrogen nucleus, the proton, because of the abundance of water in the human body; therefore, MRI images provide information about the water content of the organs, tissues, etc. MRI is producing 3D images, in general displayed as planar sections; they look similar to CT images but their information content is different.
Enhanced DWT Filtering Technique for Brain Tumor Detection
Published in IETE Journal of Research, 2022
R. Remya, Geetha K. Parimala, S. Sundaravadivelu
Scans are used for diagnosis, which allows doctor to understand whether there is tumor present or not. Tumor’s size and position can be easily identified by scan images. In the early 1900s, pneumoencephalography was developed, it drains the cerebrospinal fluid around the brain and replaced with air, it will be shown better on x-ray, but it seems dangerous to the patient. Then MRI and CT (Computerized Tomography) were developed in 1970s and 1980s [3]. MRI and CT scans will play a major role in medical field. Other categories of scans include SPECT (Single Photon Emission Computerized Tomography), PET (Positron Emission Tomography) and FMRI (Functional MRI scan). Unlike CT scans, MRI scans uses magnetic field and radio waves to produce the detailed image of organs, soft tissues, bone and other internal body organs. Both normal and abnormal tissues are clearly obtained on an MRI image than CT [4].
Analysis of SAR reduction to human head with plasma photonic crystals shield using ICCG-SFDTD method
Published in Radiation Effects and Defects in Solids, 2021
Da-Jie Song, Yun Zhang, Jin Xie, Yu-Jie Liu, Hong-Wei Yang
MRI is considered a safe technology because it relies on the spatial encoding of atomic nuclei (mainly protons) position in a static magnetic field by irradiation with radio-frequency (RF) pulses as opposed to ionizing radiation (11). MRI systems are routinely used for clinical diagnosis and can produce high-quality images with relatively low static magnetic field strengths (12). However, ultra-high-field MRI systems are required in order to achieve enhanced signal-to-noise ratio in images and to improve resolution for spectroscopy applications in the future, challenges exist as significantly strong electric field and eddy currents can result in more RF energy deposits that potentially initiate tissue heating and cause other side effects, such as alterations in visual, auditory and neural functions (13). SAR (14) is the most frequently used parameter for monitoring and quantifying the power deposition to subjects in the electromagnetic environment. Strict exposure limits to SAR levels are imposed by the International Commission on Non-Ionizing Radiation Protection.
Validation of modified feature-based 3D modeling of scoliotic spine
Published in Cogent Engineering, 2019
Sampath Kumar, Hareesh KS, Soujanya Shetty
The human spine is made up of complex anatomical structures. Therefore, pathological deformations of the spine are difficult to diagnose using X-rays. The advanced 3D imaging modalities like CT and MRI have limitations on assessment of 3D spinal deformities as they are obtained in supine position. The supine position can change the actual deformation. Although CT can provide more information for the deformity assessment, the subjects are exposed to higher levels of radiation. Since the subjects with spinal deformities may have implants and corrective tools, MRI cannot be used. Hence, stereo-radiography is the most widely used technique for 3D reconstruction of the human spine. For this purpose, we have developed a feature-based stereo-radiographic method. This paper mainly focuses on the validation of 3D models obtained through this method. It includes both qualitative and quantitative methods with respect to the gold standard.