Test
Imaging Techniques
Este test tiene tipos de pregunta que se abren en el reproductor de siempre.
Preguntas del test (25)
1Who discovered the x-ray in 1895?
- AWilhelm Rongten
- BJohann Radon
- CHounsfield
- DOldendorf
2Lossy compression file formations should never be used to store medical images.
- AVerdadero
- BFalso
3With what piece of apparatus were x-rays discovered?
- ACrooke's tube with barium platinocyanide
- BCrooke's tube with phosphorus
- CA 14C isotope and photographic film
- DA heated sample of helium
4Why is iodine a good contrast agent for x-ray imaging?
- AHigh attenuation
- BLong radioactive half life
- COnly need a small amount
- DProduces pink colouration of photographic paper
5X-rays are produced when high speed electrons strike a target material. The energy of these electrons can be converted to what, in terms of what is useful in medicine?
- ALight photons
- BGamma rays
- CAlpha particles
- DMicrowaves
6Which factors of tissues allow us to distinguish between different tissues on an x-ray image?
- AThickness/distance from source - the longer the distance travelled, the lower the intensity of x-rays detected
- BAttenuation - a measure of the material's ability to attenuate x-rays (higher attenuation = brighter image)
- COxygen concentration in the tissue
- DFluid content of the tissue
7Tissues who are more attenuating of x-rays appear brighter on x-rays (i.e. bones are highly attenuating so appear bright white)
- AVerdadero
- BFalso
8Which generation of CT scan do modern systems use?
- AGeneration 1 - dual motion pencil beam scanner in a translate-rotate mechanism
- BGeneration 2 - dual motion narrow fan beam in a translate-rotate mechanism
- CGeneration 3 - single motion with a fan beam and rotating detector and source in a rotate-rotate mechanism
- DGeneration 4 - fan beam with rotating source only and stationary-rotate mechanism
- EGeneration 5 - scanning electron beam with stationary-stationary mechanism
9Fill in the blanks to give the type of ionising radiation based off the property.
[blank_start]Alpha[blank_end] radiation is stopped by paper.
[blank_start]Beta[blank_end] radiation is not stopped by paper but is stopped by plastic.
[blank_start]Gamma[blank_end] radiation is not stopped by paper or plastic but is stopped by concrete/steel/lead.- AAlpha
- BBeta
- CGamma
10Alpha decay occurs in natural radioactive elements heavier than lead (i.e. having a relative mass of over 81)
- AVerdadero
- BFalso
11In beta-minus decay, what does a neutron break down into?
- AProton and electron
- BTwo neutrons
- CTwo electrons
- DTwo protons
12In beta-minus decay, the atomic number and mass both increase by 1.
- AVerdadero
- BFalso
13In beta-plus decay, a proton breaks down into what?
- AA neutron and a positron
- BA proton and neutron
- CA proton and electron
- DTwo protons
14Why is alpha radiation not suitable for medical imaging?
- AWon't be detectable outside of the body
- BNot safe for use inside the body
- CReleases too much thermal energy
- DIsn't found in non-toxic mediums
15What happens when a positron and an electron meet?
- AThey are converted into two gamma photons travelling in opposite directions
- BThey form two protons which travel in the same direction
- CThe positron is converted into an electron and the two orbit one another
- DThey form one neutron
16In isomeric transition, the mass, atomic number and charge of the nucleus all remain the same.
- AVerdadero
- BFalso
17Radioactive isotopes with long half lives are not suitable for use in medical imaging.
- AVerdadero
- BFalso
18Which radioactive isotope do we commonly use in medical imaging due to its half life of around 6 hours and its ability to be made in a lab?
- ATechnetium
- BPhosphorus
- CPlatinum
- DTungsten
19Why can we use the 18F isotope to monitor metabolism in tissues?
- A18F can be incorporated into fluorodeoxyglucose which the body treats as standard glucose
- B18F emits radiation in high carbon dioxide concentrations
- C18F emits radiation in high oxygen concentrations
- D18F reacts with acetyl CoA, emitting radiation
20What type of radiation does the 18F isotope emit?
- ABeta-plus (positrons)
- BBeta-minus (electrons)
- CAlpha (alpha particles)
- DGamma
21Fill in the blanks to describe the physics of MRI scanning.
Protons have the physical property of [blank_start]spin[blank_end] - they spin on their axes oriented in different directions.
When placed inside a magnetic field, the protons align and become [blank_start]parallel[blank_end].
Some protons will spin in a [blank_start]north-south[blank_end] direction, others in a south-north direction.
In the MRI scanner, a second electromagnet flips the protons off their axes, usually by [blank_start]90[blank_end] degrees.
The [blank_start]frequency[blank_end] of the coil must exactly match the [blank_start]frequency[blank_end] at which the protons are spinning.
When we turn off the second electromagnet and the proton returns to its [blank_start]resting[blank_end] spin and releases [blank_start]radio[blank_end] signals which can be detected.
Different tissues have different densities of [blank_start]water[blank_end] so take different lengths of time to return to rest - these relaxation time differences form contrasting images.- Aspin
- Bparallel
- Cnorth-south
- D90
- Efrequency
- Ffrequency
- Gresting
- Hradio
- Iwater
22Why do MRI images not show bone?
- ABone has low hydrogen content
- BBone has high calcium content
- CProtons in bone do not have spin
- DBone has high hydrogen content
23Fill in the blanks below to describe the principles of ultrasound imaging.
A short ultrasound pulse is emitted and a detector 'listens' for a [blank_start]reflected[blank_end] pulse. The time between emitting a pulse and receiving a response tells us how far away the pulse was when it was [blank_start]deflected[blank_end]. The energy of the pulse tells us how much the energy has [blank_start]depleted[blank_end] in the tissue - the properties of the tissue determine this.- Areflected
- Bdeflected
- Cdepleted
24What did Ansell and Rotblat do in 1948?
- AProduce the first image of a thyroid using radioactive iodine
- BDiscovered the X-ray
- CInvented the hydrophone for locating icebergs based on pulse-echo principles
- DDiscovered radioactivity
25Langevin invented the hydrophone to detect icebergs using pulse-echo physics ib 1915 following the Titanic disaster.
- AVerdadero
- BFalso
Información
- Descripción
- Only a few questions on the history and physics of imaging - key words found in Quizlet
- Autor
- Charlotte Jakes
- Idioma
- English
- Visitas
- 68
- Etiquetas
- Valoración
- Aún sin valoraciones Valora este test