MEDICAL ELECTRONICS
X-Rays
- extremely short wavelength of electromagnetic waves is directed at a part
of the body providing images on a photographic film placed behind the
patient.
- causes no immediate sensation but frequent exposure could damage skin and
internal organs and also could cause cancer later in life
- X-rays were discovered by Wilhelm Roentgen in 1895
Angiography
- an imaging technique that enables blood vessels to be clearly seen on X
ray film following the injection of a contrast medium
Digital Subtraction Angiography
- a type of angiography that uses computers to process images and remove
unwanted background leaving only the blood vessels to be studied
CT Scanning
- Computed Tomography
- uses combination of computer and X-rays
- X-rays are passed through different angles of the body creating cross
sectional images of tissues to be examined
- images can be computer processed to create 3D images
Radionuclide Scanning
- a radioactive substance is introduced into a patient's body and a gamma
camera detects the emission of radiation of these radionuclides to create an
image
PET
- Positron Emission Tomography
- a type of radionuclide scanning that produces 3D images
- based on the detection of positrons (positively charged electrons) emitted
by labeled substances introduced into the body
MRI
- Magnetic Resonance Imaging
- provides high quality cross sectional or 3D images of organs and
structures in the body by detecting the alignment of hydrogen atoms
- a patient is exposed to short bursts
of very powerful magnetic field and radio waves ,these bursts stimulate
protons( hydrogen nuclei) to emit radio signals, which are further detected
and analyzed by a computer
Ultrasound
- similar principle as used on the
naval Sonar (imaging by the use of reflected sound waves)
- used primarily in obstetrics because
it causes no discomfort and is completely safe to both mother and
fetus
EEG
- electroencephalogram
- records the minute electrical
impulses produced by the brain
- first used in 1928
EMG
- electromyogram
- recording of electrical activity of
the muscles
ECG
- electrocardiogram
- a record of the electrical impulses
that immediately precede contraction of the heart muscle
Electronystagmography
- recording the various types of
abnormal jerky movements of the eye to investigate their cause
Lithotripsy
- uses ultrasound to pulverize calculi
(stones) in the body
Radiotherapy
- treatment of cancer by X-rays or
other sources of radioactivity
ECE 2k1 HOME