What is an X-Ray? Flashcards
what are the different diagnostic techniques?
– X rays or radiographs (2D)
– CT or cone beam CT (3D)
– MRI (3D)
– Ultrasound (3D)
what is the definition of radiation?
- Radiation is a generic term used to describe energy that has been emitted from an object can consist of either particles or waves.
- These travel as packets of energy called photons.
what are particles?
- These are small bits of matter.
- They transfer kinetic energy by colliding with other particles.
what are x-rays?
- X rays are waves.
- This is a continuous disturbance in a medium that spreads from a source. It carries energy from one point to another.
- Travels in straight lines.
can x-ray travel through a vaccum or matter?
Can travel through a vacuum or matter. When it does travel through a matter it causes particles to vibrate around a set point. The particles do not move with the wave the wave itself is travelling through medium.
what are electromagnetic waves?
- Electromagnetic radiation waves consists of an electric and magnetic field.
- These fields vibrate at right angles to one another and at right angles to the direction of the wave.
- They all carry energy from one place to another.
- How they interact with matter depends on their frequency and wavelength.
how does the wavelength and frequency change as you move down the spectrum?
As we move down the spectrum you get a higher frequency but shorter wavelength. The properties of these different radiation waves are going to change as frequency and wavelength changes giving them their unique properties.
what material blocks more x-rays?
very dense materials like metal or enamel are going to block more x-ray so less x-rays are going to hit the detector in this region.
The less X-rays that hit the detector the whiter that part of the image is (radiopaque).
what material blocks less x-rays?
Whereas less dense structures such as the pulp tissue, dental caries block less x-rays, so more x-rays pass through and hit the detector.
The more X-rays that hit the detector the darker that part of the image is (radioluscent).
what are examples of ionising radiation?
- UV photons, X-ray and gamma are all types of ionising energy.
what does the energy of a photon depend on?
The energy of a photon depends on its frequency. The higher frequency photons have greater energy.
Is ionising radiation harmful?
Ionising radiation can cause harm to the patient. The main risk we need to be aware of diagnostic imaging, is the risk of cancer induction.
