The Era for radiology began in 1895, when a German physicist “Wilhelm Roentgen”
made the discovery of X-Rays while experimenting with electron
beams. Roentgen's remarkable discovery is one of the most
important medical advancements in human history. X-ray technology lets physicians
see straight through human tissue to examine bones and cavities with
extraordinary ease. Roentgen received the first Nobel Prize in physics for their discovery
in 1901. Plain radiography was the only imaging modality available during the
first 50 years of radiology.
Over last 40 years significant advances have taken place in radiology
creating a niche for itself and now an important part of new age medicine for
both diagnosing and treating disease.
A brief introduction
to various imaging technology available:
1.
Mammography:
It is an X-Ray based technology for examination of breast. Mammograms
can be used as screening examination, aimed at detecting early breast cancer or
better define clinically found abnormality like a lump in the breast. It should
be only used after consultation with a doctor as it involves ionizing
radiation.
2.
Ultrasound:
"Ultrasound" refers to sound
waves with a frequency
too high for humans to hear. Ultrasound images (sonograms) are made by sending
a pulse of ultrasound into tissue using an ultrasound probe (transducer). The sound
reflects and echoes off parts of the tissue; this echo is recorded and
displayed as an image to the operator. Benefits of ultrasound are that it shows
inside the human body in real time without any delay and is completely safe without
any ionizing radiation.
3.
CT Scan (computed tomography):
CT scan is an X-Ray based technology, which uses
computer-processed x-rays
to see what is inside human body without cutting it. It produces virtual
'slices' of the area under scanning. It can also generate a 3D image. CT scanning has
become the test of choice in diagnosing some urgent and emergent conditions,
such as brain hemorrhage or acute abdominal pain, where the surgeon need to
decide whether a surgery is required or not. In the past, the only option would
be to reply on clinical signs and operate beyond a certain point. With CT scan
advances, surgeon gets accurate diagnosis of the problem and location. Based on the clinical information they, may operate
only when required and at times even plan the surgery based on the images available
and reducing surgical time. CT scan uses
ionizing radiation and should be used only after consulting your doctor.
4.
MRI (Magnetic Resonance Imaging):
An MRI machine uses magnetic field to create detailed images
of the body. Human body contains water (hydrogen protons). MRI uses strong
magnetic fields to align hydrogen protons within body tissues, and then uses a radio frequency
pulse to disturb the axis of rotation of these nuclei and observes the signal
generated as the nuclei return to their baseline states. MRI is non-ionizing
and completely safe. An advantage of MRI is its ability to produce images in any
plane of the body and gives the best soft tissue contrast of all the imaging
modalities. Disadvantage includes tunnel like space leading to claustrophobia
and noise during the exam.
Nuclear medicine imaging is a specialty in imaging, which
involves administration radio-pharmaceuticals into the patient. These radio-pharmaceuticals have affinity for
certain body tissues and are labelled with radioactive tracer. The radiation,
emitting from the body is detected by a gamma camera and an image is formed.
PET CT is fusion of nuclear medicine images with a
CT scan, both acquired simultaneously. The physiological information obtained from radiotracers is overlaid with the anatomical
structures obtained via a CT scan. This improves diagnostic accuracy giving
anatomical and functional information about tissues.
PET CT is one of the significant advances in cancer
treatment. It has ionizing radiation and should be only performed under medical
supervision and after consulting a doctor.
References:
2.
http://www.sharecare.com
No comments:
Post a Comment