Joshua Cayetano
AP Physics/Period 3
Ms. Fitzmaurice
May 22nd, 2014
MRI Rough Draft
Three simple letters such as “MRI”, may leave one in question of what it’s about. But MRI stands for Magnetic Resonance Imaging. In other words, an elaborated scientific form of a x-ray. It derives from Nuclear Magnetic Resonance Spectroscopy (NMR). NMR is enabling us to identify the structure of an organic molecule, but can also be applied to the imaging of the whole body organs, to what we know as an MRI. Spectroscopy is just a technique for analyzing the structure for a molecule based off how they absorb electromagnetic radiation. MRIs are one of the most powerful tools in medical diagnosis.
Spectroscopy works because molecules absorb electromagnetic radiation in discrete packets of energy called quanta. These electromagnetic radiation we speak of is described in forms of waves. The equations v = c/ or v = c . Where a wave can be defined by its frequency v or its wavelength and c is the speed of radiation, known as “the speed of light”. Then if the frequency of the incident radiation is v, the quanta is E = hv. Where E is the energy difference, h is the height, and v is the frequency again. We are able to see the image through NMRs by a process called excitation, where the absorbed energy causes electronic motion in the molecules. The human body contains primarily fat and water. Fat and water have plenty of hydrogen atoms which give off an NMR signal because of the hydrogen nuclei.
A chemical shift, called the position of an NMR absorption depends on the density of electrons around the hydrogen. The density is controlled by the structural environment of the observed nucleus. Thus, making the shifts of the hydrogen in a molecule are import...
... middle of paper ...
...led the isocenter of the magnet. The magnetic field at this point is Bo and the resonant frequency is o. NMR spectrum with more than one signal is in result of a linear magnetic field gradient being applied to the hypothetical head with three spin containing regions experiencing different magnetic fields. This principle forms the basis behind all MRIs.
A form of MRIs is one of the first procedures, Backprojecting imaging. It’s an extension of frequency encoding. The object is first placed in the magnetic field, the a one-dimensional field gradient is applied at several angles and the NMR spectrum is recorded for each gradient. A second spectrum is recorded with the gradient now at a one degree angle to the +Y axis. This is repeated throughout the 360o between 0o and 359o. Once recorded it can be backprojecetd to the computer memory giving an image we can see.
My interest in MRI started when I first read the book “MRI, The Basics” written by the author Ray Hashemi. By the time I successfully finished my MRI clinical placement in Tehran University of Medical Sciences, I knew for sure that MRI would be the field I would be choosing to take on. What attracts me most about MRI is how beautifully scientist could create a technology that can take advantage of the magnetic moments of human body for imaging it without any harms of ionizing radiation. Although there are drawbacks to MRI, combining it with other modalities would be a more effective approach to an accurate diagnosis.
The basic principle of the spectrophotometeric technique is the measurement of interaction between energy and electrons of the substance. Spectrophotometric technique is an analytical method used for estimating concentration of metal ion in liquid solution. One of the most magnificent effects of complex formation is the change of spectral properties. The reason for light absorption by complexes are as follows.
All MRI examinations were performed with a 1.5-T MRI system (Achieva; Philips Medical Systems, Best, the Netherlands) using body coil (a phased-array coil).T1, T2 and fat suppressed T2-weighted imaging as well as diffusion weighted imaging were performed during the same MRI examination in all patients. Images will acquired with the patient is in supine position with head pointing to the magnet (head first supine; HFS). The body coil was securely tightened using straps to prevent respiratory artifacts. The center the laser beam localizer will placed over symphysis pubis. Chloral hydrate syrup at a dose of 1 ml/kg body weight was needed for children less than 5 years for sedation during MRI examination.
Other testing procedures that are commonly employed, in order to gain a better visual image of the excitatory activity in the brain are the PET scan and the MRI. According to Kalat (2004), these methods are non-invasive, meaning that they don’t require the insertion of objects into the brain, yet they yield results that allow researchers to record brain activity. The PET scan (positron emission tomography) involves the researcher injecting a radioactive chemical into the patient’s body, which is then absorbed mainly by the brain’s most active cells. With the use of radioactive detectors, placed around the patient’s head, a map is produced that shows which areas of the brain are most active.
After graduating with my Bachelor’s degree, I continued to work as a staff MRI technologist. Even though I loved what I did and had a passion helping people, the lack of diversity within radiology and its limited room for growth bothered me. I decided to look into furthering my career and found an interest in Health Information Technology. Upon researching many different schools through the country offering an online graduate Health Information Technology program, the University of Michigan in Dearborn stood out to me. Medicine and technology have both always been a part of my life, and I am very happy and excited that the chance for it to play a new part has finally arrived. I’m motivated to learn how I can combine the science of information with clinical knowledge so I can help to better patient care and
This specific lab will focus on the two main variants of Atomic Absorption Spectroscopy: flame AA spectroscopy, and spectroscopy using a graphite furnace. The lab will also introduce and teach how to deal with both systematic and random error when using Atomic Absorption Spectroscopy.
One of the most recently new advances in radiology is the use of magnetic resonance imaging (MRI). MRI has been around for the past century. It was at first called Nuclear Magnetic Resonance (NMR) and then it changed to MRI once there was an available image. Walter Gerlach and Otto Stern were the first scientists to start experimenting with the magnetic imaging. Their very first experiment was looking at the magnetic moments of silver by using some type of x-ray beam. The scientists then discovered this was by realizing that the magnetic force in the equipment and in the object itself. In 1975, the first image was finally created using and MRI machine. The scientists used a Fourier Transformation machine to reconstruct images into 2D. The first images ever use diagnostically was in 1980. This is when hospitals began to use them. At first the images took hours to develop and were only used on the patients that needed it most. Even though MRI has been around for a long time, it has advanced and has been one of the best imaging modalities recently (Geva, 2006).
Do diagnostic Medical Sonographers actually help begin a new life? Yes, according to researchers they do help patients indicate any problems that there may be and what may be expected. This essay will talk about Diagnostic Medical Sonographers and everything it takes to become one and how to become successful as well as why they are important to our global community. Sonographer’s are also known as ultrasound Technicians, they are very important in the medical field because they help patients and physicians diagnose and treat diseases as well as other medical information. The following paragraphs will talk about the information of the Salary and also the Job Responsibilities. With the technicians continuously providing
Ultrasound Technicians are very valuable in the world of health care. Also known as Diagnostic Medical Sonographer, an Ultrasound Technician uses special machines and equipment that operates on sound waves to determine or diagnose medical problems for patients. There are specializations within this field in which some individuals explore. For instance, areas of specialization includes but not limited to; pregnancy, heart health, gynecology, and abdominal sonography. Although each specializing branch has its own distinctive function, they all involve probing the body to facilitate doctors with diagnoses.
The machine is a 100% accurate method of disease detection throughout the body and is most often used after other testing methods have failed to provide sufficient information to confirm a patient’s diagnosis. According to journalist Mary Bellis, two brilliant men Felix Block of Stanford University and Edward Purcell of Harvard University discovered MRI in the 1930s. Because of their discoveries they used nuclear magnetic resonance (NMR) to study composition of chem...
Magnetic resonance angiography (MRA), similar to CT, uses a magnetic field and pulses of radio wave energy to provide pictures of blood vessels inside the body. A dye is often used during the procedure to make blood vessels appear clearer. Lastly, a cerebral angiogram may be done. This is an x-ray test, where a catheter is inserted into a blood vessel, usually in the groin or arm, and moved from the vessel into the brain. A dye is also injected.
Radiology is one of the few so-called “physical-science”-based fields of medicine, making it a challenging and rewarding application of an academic interest in science. It combines advanced knowledge of human physiology with principles of atomic physics and nuclear decay, electricity and magnetism, and both organic and inorg...
23. S. Alwarappan, S. Boyapalle, A. Kumar, C.-Z. Li and S. Mohapatra, J. Phys. Chem. C, 2012, 116, 6556–6559
The detection of neural activation in fMRI relies on perturbations of the water magnetization that are associated with the hemodynamic change (3).
A ferromagnetic material is composed of many microscopic magnets known as domains. Each domain is a region of the magnet, consisting of numerous atomic dipoles, all pointing in the same direction. A strong magnetic field will align the domains of a ferromagnet, or in other words, magnetize it. Once the magnetic field is removed, the domains will remain aligned, resulting in a permanent magnet. This effect is known as hysteresis.