Radiology

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Radiology

• Study of radiation of radioactive substances

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Radiology

• Is the study of diagnosis of disease using
  radiant energy (radiation)

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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

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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
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Radiology

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

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Diagnostic radiology

• Is imaging using external sources of radiation
  e.g. X-rays

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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

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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 dont show up on x-ray or arent
  radio-opaque e.g. GIT
• Radio-opaque substances or contrast medium are
  given GIT show on film

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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

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Computed Tomography (CT Scan)

• Can differentiate different body parts that
  cannot be done through conventional X-rays
• Is painless

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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

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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

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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

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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

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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