Statistics
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In general MRIs have had a positive impact in the sector of diagnostic imaging and it continues to grow throughout the years. The numbers of computed tomography (CT) and magnetic resonance imaging (MRI) scanners have grown significantly since they were introduced in Canada (in 1973 and 1982 respectively). From 1990 to 2006, the number of CT scanners has grown by 180 (91%), whereas the number of MRI scanners has grown by 177 (932%). In this case the number of MRIs have increased drastically as physicians slowly rely on this technology more for a variety of uses.
In Canada, the number of MRIs in free-standing (or non-hospital) imaging facilities has grown every year from 2 in 1998 to 32 in 2006. The number has gradually increased. The growing use of MRI is related to its advantages against other medical imaging technologies. |
Advancement In Neurology
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Neurology is the study of the brain and numerous disorders that affect it. Imaging techniques like MRI allow doctors to observe the inflammatory changes in the white matter of the brain found often in Multiple Sclerosis.
Injecting dye into blood allows MRI to pick up the areas of inflammation in detailed images. MRIs can be used to measure oxygenation levels levels in certain parts of the brain. This is helpful because when doing certain activities such as reading a certain part of the brain will use up oxygen quicker which shows up on the scan. This technique is used to improve the accuracy of brain surgery for forms of epilepsy that can't be controlled by drug treatment. In 1991, Hare and two graduate students published a landmark study suggesting that the brains of psychopaths underutilize regions that integrate emotion and memory with other information. The findings supported the long-held suspicion that the destructive behaviour of psychopaths had a neurobiological basis (Kaihla 2003).
The study of this topic takes advantage of the university's 18-month-old, state-of-the-art General Electric magnetic resonance imaging (MRI) facility - and the expertise of its scientists, radiologist Bruce Forster and physicist Alex MacKay. The unit itself, visible through a window from a control room, is a small white room equipped with a gurney that slides along a horizontal track into a short tunnel. That is where subjects lie as the machine probes their brains with magnetic torque. When Hare and his colleagues tested the procedure on a psychopathic subject last fall, the convict viewed the computer prompts through mirrors aimed at a rear-projected screen. And because the MRI is thrown off by any metal in its vicinity, the subject had to respond by pressing a touch-pad connected to a computer by fibre optics instead of a keyboard or joy stick wired with metallic cable. Capturing brain images at the rate of one every 40 milliseconds or so, the experiment effectively creates a video of the psychopath's brain as it processes emotional information (Kaihal 2003). In this case, MRIs are used to research about the workings of the brain using functional MRI to determine the brain activity of psychopaths and "normal" people. |
Advancement in Mammography
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Breast magnetic resonance imaging (MRI) is an imaging test that creates detailed pictures of the inside of the breasts. Although breast MRIs are not regularly used for breast cancer screening, it can help detect breast cancer in its earliest stage for women with a high risk for developing the disease. With the current equipment for mammography, it is not very useful for women below the age of fifty because MRIs are unaffected by the age of a woman when the scan is conducted. They can detect small tumours in the breasts easily compared to mammography. Rather than replacing mammography to detect breast cancer, MRIs are used as a complementary screening tool.
MRIs are more likely to detect cancer compared to a mammography however they can still miss some things a mammography easily detects. |
Negative Impacts Of MRI
For Canada, the rate of CT exams is more than three times the rate of MRI exams, although the number of CT scanners is less than twice the number of MRI scanners. Typically, a CT exam is a less costly procedure than an MRI exam and takes less time. Therefore more people choose to have a CT scan due to its convenience with less waiting and less money spent. For MRI scans there is often a long wait to get a scan done spanning up to a whole month.
In addition, there is a fast growing rate of unneeded scans being done on patients and misuses of the medical imaging equipment. This occurs when MRI is used for diagnosis in replacement of a different imaging. For example, MRIs have an increased sensitivity that may cause areas of the breast that do not have cancer to appear abnormal, producing an increased number of false-positive test results. False-positive test results indicate cancer when no cancer is actually there. This may lead to unnecessary biopsies (removal of breast tissue for further study) and increased anxiety for many women. This is an example of the impact of misusing this high tech equipment.
In addition, there is a fast growing rate of unneeded scans being done on patients and misuses of the medical imaging equipment. This occurs when MRI is used for diagnosis in replacement of a different imaging. For example, MRIs have an increased sensitivity that may cause areas of the breast that do not have cancer to appear abnormal, producing an increased number of false-positive test results. False-positive test results indicate cancer when no cancer is actually there. This may lead to unnecessary biopsies (removal of breast tissue for further study) and increased anxiety for many women. This is an example of the impact of misusing this high tech equipment.