1. Study of radiation of radioactive substances
Radiology
Study of radiation of radioactive substances

2. Radiology
Is the study of diagnosis of disease using radiant energy (radiation)

3. What is radiation
Radiation is energy in the form of electromagnetic waves
Ultraviolet Light, gamma rays, heat and sound are types of radiation.
ionizing radiation is used in Xrays
it changes electrical charge of atoms & may have an effect on body cells
A radioisotope is a substance that can emit radiant energy

4. Word Parts Word root Combining form Meaning Radi radi/o
invasive X-rays by an X-ray machine
Roentgen
roentgen /o
X-rays
Tom
Tom/o
slice or section
Son
son/o
sound
Echo
echo-
reflection of sound
Therm
Therm/o
heat
Scint
scint/o
emitting sparks /light
Cine
cine,cinemat/o
moving film

5. Radiology Is a branch of medicine dealing with radioactive substances
Used to diagnose and treat diseases using radiant energy
Diagnostic
Therapeutic
Nuclear medicine

6. Diagnostic radiology
Is imaging using external sources of radiation e.g. X-rays

7. Radiography (X ray)
Small amount of radiation is passed through the body to create a film of picture.
The image is called a radiograph / radiogram
X-rays are taken by a radiographer
X-rays are interpreted by a radiologist

8. Radiograph (X-ray)
Some body parts block the X-rays and are said to be radio-opaque
They appear white on the films e.g. bones
Other body parts don’t show up on x-ray or aren’t radio-opaque e.g. GIT
Radio-opaque substances or contrast medium are given GIT show on film

9. Computed Tomography (CT Scan)
Combines principles of X-rays and computer technologies
A machine called a scanner takes a series of X-rays of body cross sections i.e. (tomographic)
Machine rotates a full circle over the body part being scanned
A computer then calculates and converts the rate of absorption and density of the X-rays into a three dimensional picture on a TV screen

10. Computed Tomography (CT Scan)
Can differentiate different body parts that cannot be done through conventional X-rays
Is painless

11. Magnetic Resonance Imaging (MRI)
Uses magnetic fields and radiofrequency waves
no ionising radiation
Patient is positioned within a magnetic field as radio waves are conducted through the body part.
Energy is absorbed through the body part then released.
Computer processes the released energy and produces the picture

12. Therapeutic Radiology
Treatment of disease using radiation e. radiotherapy
Uses superficial and deep x-ray machines or radioisotopes e.g. radioiodine
Used to treat malignant neoplasms and

13. Positron Emission Tomography
Provides information about activity of different body parts
Ring of detectors surround the patient
Patient receives injection of a Positron radioactive material called a tracer.
PET Scanner has a camera that detects emissions from the tracer and the computer creates two and three dimensional images
Areas that are more active in taking up the tracer appear brighter than normal tissue

14. Sonography / Ultrasound
Use of high frequency sound wave to visualise body parts
Ultrasound waves are sent through a scanning device known as a transducer
These waves are then reflected of body structures and converted into images

15. Use of contrast
Some imaging procedures require use of contrast medium to more easily visualise body structures
Includes Barium, iodinated compounds and gases
Maybe injected, swallowed or introduced through an enema or catheter Act 1