Humanity, constantly learning, growing,
and facing more challenges each second
of the day. Whether the challenges
are mental or purely physical. We have found more
efficient, safer, and easier ways of doing
the tasks we may face. From moving cargo, to
sending information via the Internet.

Probably the greatest accomplishments we have
made, are in the studies of medicine/treatment.

And to be specific, the study of radiology.

Radiology, the process of working and viewing
inside the human body without breaking the skin. By using radiant
energy, which may take the form of x rays or other types of radiation,
we are able to diagnose and treat many diseases and injuries. Both
diagnostic and therapeutic radiology involve the use of ionizing radiation
( Beta, Alpha, Gamma, and x rays), with the exception of the MRI, which
uses a magnetic field rather then radiation.

Radiology is classified as being either
diagnostic or therapeutic. Diagnostic radiology is an evaluation
of the body, by means of static or dynamic images or anatomy, physiology,
and alterations caused by injury or disease. A majority of these
pictures are formed by passing a low or high level of x rays through the
part of the body being examined, producing the static image on film.

This image is called a radiograph or x ray picture. The image it\'s
self may have many forms. It could be a common radiograph, such as
a chest x ray; a tomograph (Greek for "section"), which is a radiograph
obtained by timing the x ray exposure to correspond with the movement of
the x ray tube and film in opposite directions around the plane of the
body; or, finally, a computerized axial tomography (CAT or CT) scan.

Which is a computer analysis of a sharply limited, thin x ray beam passed
circumferentially through an area of the body, giving the doctor of Technician
a cross-sectional image. Much like that of slicing a loaf of bread
into sections.

Other images may be obtained by using ultrasound
or MRI, or by recording the activity of isotopes internally administered
and deposited in certain parts of our body. This practice is called
nuclear radiology or nuclear medicine. This include such techniques
as a PET scan, or positron emission tomography, which uses patterns of
the positron decaying to study metabolism reactions in the body. PET requires
a cyclotron as an on-site source of short-lived, positron-emitting isotopes.

The isotopes are injected into the patient along with a glucose related
compound, and the positrons collide with the electrons in the body
to produce photons. The photons are then tracked by a tomographic
scintillation counter, and the information is processed by a computer to
provide both image and data on blood flow and metabolic processes within
bodily tissues. PET scans are particularly useful for diagnosing
brain tumor and the effects of strokes on the brain, along with various
mental illnesses. They are also used in brain research and in mapping of
brain functions.

Another form of imaging is ultrasound.

Ultrasound, which uses very high frequency sound, is directed into the
body. And because the tissue interference\'s reflect sound, doctors
are able to produce, by use of a computer, a photograph or moving image
on a television. Ultrasound has many application uses on the body,
but is more commonly used in examinations of the fetus during pregnancy,
because use of radiation may affect the outcome of the baby. Some
other practices for ultrasound include examination of the arteries, heart,
pancreas, urinary system, ovaries, brain, and spinal cord. And because
sound travels well through fluids it is a very useful technique for diagnosing
cysts( which are filled with fluid), and fluid filled structures such as
the bladder. And since sound is absorbed by air and bone it is impossible
to use a ultrasound on bones or lungs.

The sound waves are produced by a random
oscillating crystal, and are inaudible to humans. A instrument called
a transducer is used to transmit the sound waves and receive the echoes.

The transducer must be in close contact with the skin, and a jelly like
substance is used to improve the quality of the transmission.

And last of the diagnostic imaging tools
is the MRI. MRI, which stands for Magnetic Resonance Imaging.

Was a technique developed in the 1950\'s by Felix Bloch, and is the most
versatile, powerful, and sensitive tool in use. The process of MRI
was originally called NRI (Nuclear Resonance Imaging), but was found to
be to confusing due to the fact that MRI\'s don\'t use radioactivity and
ionizing radiation. The MRI generates a very powerful electromagnetic
field, which allows the radiologist to generate thin-section images of
any part of the body. Also it can take these images from any direction