Introduction

Computed Tomography (CT) is a medical imaging method employing tomography created by computer processing. The word "tomography" is derived from the Greek word "tomos" (slice) and "graphein" (to write). Computed tomography was orignally known as the "EMI Scan" as it was developed at a research branch of EMI, a company best known today for its music recording business. It was later known as computed axial tomography (CAT or CT scan) and body section rontgenography. Although the term "computed tomography" could be used to describe positron emission tomography and single photon emission computed tomography, in practice it usually refers to the computation of tomography from X-ray images, especially in older medical literature and smaller medical facilities. The first commercially viable CT scanner was invented by Sir Godfrey Hounsfield in Hayes, United Kingdom at EMI Central Research Laboratories using X-rays. Hounsfield conceived his idea in 1967, and it was publicly announced in 1972. Allan McLeod Cormack of Tufts University in Massachusetts independently invented a similar process, and both Hounsfield and Cormack shared the 1979 Nobel Prize in Medicine. CAT scans use both X-rays and computer technology to create detailed images of body parts, including the heart and other organs, bones, and muscles. Unlike traditional X-rays, the CAT scan X-ray beam moves around, creating many different views or “slices” of its intended subject. A computer is then used to combine these picture slices, resulting in highly detailed three-dimensional images that help cardiologists and other physicians to clearly visualize and diagnose disorders.

Diagnostic Use

Since its introduction in the 1970s, CT has become an important tool in medical imaging to supplement X-rays and medical ultrasonography. It has more recently begun to also be used for preventive medicine or screening for disease, for example CT colonography for patients with a high risk of colon cancer. A number of institutions offer full-body scans for the general population. However, this is a controversial practice, given its lack of proven benefit, cost, radiation exposure, and the risk of finding 'incidental' abnormalities that may trigger additional investigations.

Head

CT scanning of the head is typically used to detect:

1. bleeding, brain injury and skull fractures
2. bleeding due to a ruptured/leaking aneurysm in a patient with a sudden severe headache
3. a blood clot or bleeding within the brain shortly after a patient exhibits symptoms of a stroke
4. a stroke
5. brain tumors
6. enlarged brain cavities in patients with hydrocephalus
7. diseases/malformations of the skull
8. evaluate the extent of bone and soft tissue damage in patients with facial trauma, and planning surgical reconstruction
9. diagnose diseases of the temporal bone on the side of the skull, which may be causing hearing problems
10. determine whether inflammation or other changes are present in the paranasal sinuses
11. plan radiation therapy for cancer of the brain or other tissues
12. guide the passage of a needle used to obtain a tissue sample (biopsy) from the brain
13. assess aneurysms or arteriovenous malformations

Chest

CT can be used for detecting both acute and chronic changes in the lung parenchyma, that is, the internals of the lungs. It is particularly relevant here because normal two dimensional x-rays do not show such defects. A variety of different techniques are used depending on the suspected abnormality. For evaluation of chronic interstitial processes (emphysema, fibrosis, and so forth), thin sections with high spatial frequency reconstructions are used — often scans are performed both in inspiration and expiration. This special technique is called High Resolution CT (HRCT). HRCT is normally done with thin section with skipped areas between the thin sections. Therefore it produces a sampling of the lung and not continuous images. Continuous images are provided in a standard CT of the chest.

For detection of airspace disease (such as pneumonia) or cancer, relatively thick sections and general purpose image reconstruction techniques may be adequate. IV contrast may also be used as it clarifies the anatomy and boundaries of the great vessels and improves assessment of the mediastinum and hilar regions for lymphadenopathy; this is particularly important for accurate assessment of cancer.

CT angiography of the chest is also becoming the primary method for detecting pulmonary embolism (PE) and aortic dissection, and requires accurately timed rapid injections of contrast (Bolus Tracking) and high-speed helical scanners. CT is the standard method of evaluating abnormalities seen on chest X-ray and of following findings of uncertain acute significance. Cardiac CTA is now being used to diagnose coronary artery disease.

More than 62 million scans are ordered each year, according to the 2007 New England Journal of Medicine study. 31% of 62 million (19,2 million) is used for lung CT's. Now to one having no spiritual eye but instead periphal of a carnal view, then CT Scans and Medical Imaging sounds as if its a good investment in technology. You might think "hey buddy, when cardiac CAT scans are used during an emergency situation, they can provide critical diagnostic information about coronary blood flow that can help save a patient’s life", which I would totally agree, but having a spiritual eye you can see into the retnal of the technology. What the public is not told about these machines, is that they produce an astounding amount of radiation exposure for the patient, often the equivalent of up to 750 chest X-rays. The problem is that too many health care professionals casually recommend these scans to patients who are asymptomatic and who just want to know what’s going on inside their bodies. The radiation exposure from these tests can often lead to DNA breaks that may foster the initiation of cancer.

The AMA is run by criminal individuals who's desire it is to reduce the population of the world down to a suitable size that would be subjects in their New World Order. Their machines and medicines are not designed to help cure any form of illness or disease, instead they are designed to manage them and control them and iniaite them, why, because doing so keeps them in business making profits. The National Council on Radiation Protection and Measurement reveals that Americans' exposure to radiation has increased more than 600 percent over the last three decades. Most of that increase has come from patients' exposure to radiation through medical imaging scans such as CT scans and mammograms. Most patients have no awareness of the dangers of ionizing radiation due to medical imaging scans. Virtually no patients and few doctors actually realize that one CT scan exposes the body to the equivalent of 750 chest X-rays. Most women undergoing mammograms have no idea that the radiation emitted by mammography machines actually causes cancer by exposing heart and breast tissue to dangerous ionizing radiation that directly causes DNA damage. Even low doses of radiation can add up to significant increases in lifelong cancer risk. The medical profession is on the verge of creating a dramatic increase in the number of cancer cases due to excess use of diagnostic tests that expose the patient to dangerously high levels of radiation.

In fact, some of these tests expose the patient to more radiation than experienced by Japanese survivors of the atomic bomb blasts at Hiroshima and Nagasaki. A study published in the New England Journal of Medicine (2007) found that survivors of the 1945 atomic bombs unleashed on Japan during World War II still faced significant increases in lifetime cancer risk. And the levels of radiation to which these particular study subjects were exposed is equivalent to receiving only two or three CT scans. A couple of CT scans can expose your body to as much radiation as standing a few miles from an atomic bomb explosion. Exposure to CT scans and mammograms today can lead to cancer much later in life. CAT scans present many significant risks, especially when used for screening people with no signs or symptoms of disease. Too many people, including health care professionals, are not aware of these risks and, as a result, are endangering health and even lives. Cardiac CAT scans do have an appropriate place as an important diagnostic tool. While the intent is to use these tests to diagnose potentially lethal heart disease, the fact of the matter is that in doing so they are creating other problems, and one is causing cancer. Medical imaging does more than just detect cancer, it also causes cancer, and to the public that's a problem, but to the AMA, it's in the financial interests of them and their drug companies and cancer clinics that profit from treating cancer.