| Question | Answer |
| 34. What is the meaning of “single”, “double” and “triple” contrast? | single- using a single contrast media in the patient at 1 time
double- using 2 contrast media or routes in a patient at 1 time
triple- using three contrast media or routes in a patient at 1 time
routes can be: oral, IV, rectal.
media: air, dye |
| 20. What is the physical basis for X-ray beam attenuation? | absorption
scattering
absorption is the interaction with the electrons in the substance through which it passes, causing ionization |
| 35. What kind of sensitive element is used in CT equipment? | scintillation detector |
| 67. Define the Ultrasound | sound waves with frequency greater than 20KHz
above the range of human hearing (20-20,000 Hz) |
| 115. Name the corpuscular rays, used for radiotherapy | electrons
protons
slow neutrons
alpha, beta, pi mesons |
| 22. What is the source of diagnostic contrast on X-ray studies? | specific degree of attenuataion of roentgen beam by different tissues |
| 29. What is the concept of natural X-Ray contrast? | the differences in attenuation of the beam by adjacent tissues is significant enough to be seen by the human eye on the x ray image |
| 1. Name the parts of Radiology | diagnostic
interventional
therapeutic |
| 77. What is the Pulse Repetition Frequency (PRF)? | no. of pulses of repeating signal produced in one second (unit time) |
| 76. What is the meaning of the term “refraction”? | change in direction of the wave when it enters a new medium (bending)(due to a difference in speed in the different mediums) |
| 121. Name the most radioresistant tissues | bone
muscle
neural tissue |
| 23. Name the sensitive elements of receiving devices, used for X-ray studies | photographic film
fluorescent screen
charged semi-conductor plate
scintillation detector |
| 25. What is the relationship between fluorescent screen shining and attenuation? | x-rays pass through a patient's body and cause the fluorescent screen to light up when they strike. Some parts of the body attenuation is more than others, so the amount of x-rays hitting the screen at any one spot depends on what they had to pass through |
| 56. What is principle of morphological studies in NM? | administer RPP
monitor distribution in studied organs and construct image |
| 2. Define the parts of radiology | therapeutic- uses ionizing radiation for treatment
interventional- provides the possibility to perform invasive diagnostics and low invasive treatment procedures under imaging guidance |
| 7. When did G.Haunsfield perform the first CT study? | 1972- 70's |
| 66. Define, what is the wavelength | the distance between two consecutive points in the same phase on a wave
eg. trough or a crest |
| 112. Advantages of Ultrasound as a IR procedures guidance tool | in real-time
non-invasive (no ionizing radiation)
needle aiming and guiding capability
doppler capability
endocavity approach(endorectal/vaginal)
can be done repeatedly
cost-saving
no surgical trauma
no surgical aneasthesia
no contraindications |
| 36. Principle of “In-Vivo” and “In-vitro” studies | In vivo - investigation performed by administering the patient with NM contrast media
study is done using the living body
in vitro- (glass)
done on patient's blood,tissue sample,excretions
in a controlled env. outside the living body |
| 125. Name the types of radiotherapy due to expected results | radical
palliative
symptomatic |
| 52. What is the sensitive elements scintillation detector? | NaI crystal
photomultiplier
(gamma rays) |
| 91. How is the axial resolution of pulse-waive ultrasound system calculated? | Axial resolution = spatial pulse length (SPL)/2
where SPL = λ × no. of cycles
improved by higher frequency (shorter wavelength) transducers at the expense of penetration
Higher frequencies--> image structures close to the transducer |
| 48. What are the requirements the NM contrast media (RPP) have to meet? | radiopharmacopreparation
nontoxic
strong β or γ emission
property of specific uptake (relationship to definite organ/tissue)
optimum ESP (effective semiexcretion period) |
| 85. What is the “Doppler Shift”? | the difference between incident and reflected frequency |
| 37. Basic principle (concept) of Nuclear Medicine studies | detection and subsequent processing of radioactive radiation of the investigated probe (human body/tissues) |
| 54. What is the advantage of gas-discharge counter? | small size of the sensitive element |
| 105. To what frequency radiofrequency signal should be patient applied in order to get the magnetic resonance phenomenon? | Larmor frequency |
| 103. What is the unit of magnetic filed strength ? | tesla; T |
| 68. What is the frequency range, mainly used in Diagnostic Ultrasound | 1-20 MHz |
| 47. What is the source of diagnostic contrast on NM studies? | difference in radioactive radiation emitted by the investigated organ and the surrounding
more the difference, better the contrast, better the sensitivity |
| 100. What is the net magnetization of spin ensemble without external magnetic field? | 0 |
| 49. What are the possible ways of NM contrast media (RPP) administration? | peroral/enteral
parenteral
inhalent |
| 44. Which type of radioactive radiation is electromagnetic? | gamma
high frequency; short wavelength |
| 6. When was the thermal image used for diagnosis for the first time? | early sixties |
| 9. What’s the basic concept of Diagnostic Radiology? | make investigated organ visible
get the image of the investigated organ |
| 8. Who generated the idea of NMR phenomenon possible application for diagnostic imaging? | p. lauterbure |
| 90. Name the types of detail (spatial) resolution | axial
lateral |
| 124. Name the effects of ionizing radiation, used for nononcological pathologies treatment | analgesic
spasmolytic
anti-inflammatory
anti-secretory
immunosuppresive |
| 72. Which parameter determines the medium acoustic properties? | acoustic property is measured as impedence
(impedence = density X propagation speed)
(z=pc)(row c)
so density? |
| 96. Name the basic components of MRI equipment | strong magnet
strong computer
generator of RF pulse
receiving coil |
| 46. What is the meaning of the term “effective semiexcretion period”? | the time taken for the radioactivity of the administered RPP to be halved to its initial value by physical break-up and biological excretion processes |
| 32. What is the concept of artificial X-Ray contrast? | change the attenuation of the roentgen beam by the investigated area or the background SIGNIFICANTLY so that the difference is enough to be visualized on the x-ray image |
| 11. What can we achieve increasing Signal/Noise Ratio? | increased sensitivity |
| 114. Name the electromagnetic rays, used for radiotherapy | x rays
gamma rays
dampened radiation |
| 45. What is the meaning of the term “half-life time”? | the period of time for the radioactivity to decrease to half of the initial amount |
| 107. Name the MR relaxation types | Longitudinal Relaxation (Spin-Lattice Interaction)
Transverse Relaxation (Spin-spin interaction) |
| 97. Name the advantages of MRI study | no ionizing radiation
air and bone not a hindrance for visualization
lot of criteria for imaging (T1T2 relaxation times, proton density)
possibility of IN-VIVO NMR spectroscopy |
| 79. What is the Pulse Length? | length covered by one pulse |
| 118. What is RAD and it’s unit | radiation absorbed dose
(the energy absorbed by tissues)
unit- G gray(s) |
| 40. Name the types of radioactive radiation | corpuscular: alpha, beta
electromagnetic: gamma |
| 123. The main principle of radiotherapy | maximum impact on tumour
minimum damage to normal tissues |
| 2. Define the parts of Radiology | diagnostic- uses the definite/different types of radiationand mechanical vibration to study the structure and function of normal and abnormal organs and tissues of the human body |
| 120. Name the most radiosensitive tissues | hematopoietic tissues
small bowel mucosa
gonads |
| 60. What is the main advantage of thermography? | non-invasive |
| 81. What is the unit of sound attenuation? | decibel
dB |
| 21. What does X-ray absorption depend on? | chemical composition
density
thickness
greater the molecular weight, density, thickness, greater the absorption |
| 27. How can we get the image of one plane performing X-ray planigraphy (conventional tomography)? | movement of the xray tube and the film cassette in certain specified directions produces an image which shows the structures in detail in the predetermined plane while blurring the structures in the other planes |
| 24. What is the relationship between X-ray film darkening and attenuation? | the greater the x ray density passing through, the darker the image
(less attenuated, more dark)
(the more the attenuation, the lighter the image)
(so bone appears light) |
| 3. Name the parts of Diagnostic Radiology | x-ray/roentgenology
nuclear medicine-radioisotope diagnostics
diagnostic ultrasound
NMR/ MRI
thermography |
| 15. Name the X-rays main properties | 1. em radiation
2. straight lines
3. penetrates tissues
4. different attenuation
5. not perceived
6. ionizing
7. photochemical effect
8. fluorescent effect
9. ability to change charged particles
10. affects gm tube/scintillation detector |
| 86. Does Doppler Shift depend on insonation angle? | Yes,
doppler shift Fd = 2f0 Vcos α\c
if the angle is 0, Fd=1
if the angle is 90, Fd=0
α = 0 , Fd = 1
α = 90 , Fd = 0 |
| 16. Name the parts of the X-ray tube principal scheme | anode
cathode
collimator
produced by converting electrical energy into em waves
electrons accelerated from -ve cathode to +ve anode
strike the target
decelerated rapidly
lost energy converted to heat + X rays |
| 30. The region, where natural X-ray contrast is the most prominent, is: | pelvis
then thorax? |
| 84. What is the physical nature of Doppler Effect? | the incident sound frequency is different from the reflected sound frequency for a moving reflector |
| 70. What medium parameters determine the wave propagation speed in this medium? | medium stiffness
medium density |
| 19. What is generally the meaning of “beam attenuation”? | decrease of roentgen beam intensity
decrease of roentgen beam energy
by absorption, reflection, and scattering through a medium |
| 26. What is the meaning of the term “superpositioned image”, which is referred to plain X-ray study? | the 3 dimensional structure is merged into one plane to give a 2 dimensional image
so you cannot say which is in front or behind
everything is overlapped |
| 89. What is concept of detail (spatial) resolution? | depends on the smallest separation between two reflectors which can produce separate echoes on the instrument display |
| 28. What is the main advantage of spiral CT versus conventional one? | -no superimposed image
-more detailed due to high contrast (t1/2; proton)
-3D image with saggittal, coronal, and axial views |
| 13. Name the types of rays, used in Diagnostic Radiology | em--> gamma, x ray, infrared, radiowaves
corpuscular--> beta
mechanical--> ultrasound
to study structure and unction of normal and abnormal organs and tissues of the human body |
| 93. What is concept of “Real-Time Imaging”? | temporal resolution: measurement with respect to time |
| 51. What kind of detectors are used for NM studies? | scintillation detector
gas discharge counter |
| 82. How can we calculate the sound attenuation in tissues, knowing the sound frequency? | attenuation= (1/2)(frequency MHz)(path length cm)
=1/2fl |
| 55. What is principle of functional studies in NM? | administer RPP
monitor accumulation and lead out processes |
| 61. Name 2 main factors, the heat production by tissues depends on | blood supply
metabolism |
| 50. What is the advantage of “In-Vitro” studies? | no exposure to ionizing radiation
can determine different substances at critically low concentrations |
| 110. The main concept of Interventional Radiology (IR) | radiologist can see the pathology better than a surgeon after invasion into the body
IR is diagnostic and low invasive treatment procedures performed under imaging guidance using the percuataneous and endocavity approach and also intra-operative study |
| 59. What kind of radiation is detected on thermography studies? | infrared |
| 117. Name the cell response phases to ionizing radiation, leading to cell death | altered biochemistry
altered DNA
nucleus swelling
membrane disruption |
| 5. When did H.Bekkerel invent Radiactive rays? | 1896 |
| 98. Which chemical element is used for MR diagnosis and why? | H (hydrogen)
-->most common element found in the human body
-->highest sensitivity for magnetic resonance |
| 39. Is the radioactive radiation uniform, homogenous? | homogenous-->in a beam of radiation containing photons of the same wavelength
heterogenous--> in a beam/bundle containing photons of many wavelengths |
| 41. What is the penetration ability of radioactive rays? | alpha- cannot penetrate thin sheet of paper
beta- 1cm/ skin
gamma- whole body/few cm of lead |
| 106. Which magnetization creates the MR signal? | the rotating transverse magnetization creates the MR signal
M-xy |
| 53. How is the radioactive radiation detectyed by gas-discharge counter? | sealed metallic tube -ve cathode(tube) and +ve anode (rod)
-filled with argon gas
-no current b/w the anode and cathode
-if there is radiation, argon gas ionized
-current flows/ electric discharge
-measured as a sound/reading on screen (b rays) |
| 101. The magnetization vector M appears, when the investigated probe (patient) is applied to ………………. | an external magnetic field? |
| 71. What is the sound propagation speed in soft tissues? | 1.54 mm/μs
1540 m/s |
| 116. Define the unit (and derived units) of ionizing radiation energy | corpuscular radiation--> electron volt
(KE gained by an electron in an electrostatic field of 1V)
KEV (1000)
MEV(million)
electromagnetic radiation-->quantum (photon)
=hv (planck's constantXfrequency) |
| 88. What are the main (basic) 2 formats of ultrasound transducers? | linear
sector |
| 73. What is the physical nature of “Echo”? | sound reflection |
| 95. Name the basic types of Doppler study | Continuous wave Doppler
Pulsed wave Doppler
(CW-->spectral)
(PW-->spectral, color, power (amplitude and echo energy) |
| 64. What are the main parameters of any wave? | frequency
wavelength
period
amplitude
propagation speed
intensity |
| 87. How is the sound beam generated by Ultrasound Transducer? | the transducer has a piezoelectric element in between two electrodes
an oscillating current is applied
this causes the piezoelectric element to vibrate rapidly
producing ultrasound waves
the summation of all the waves produces an ultrasound beam |
| 63. Name the sound wave variables | pressure
density
temperature
particle motion |
| 43. Which type of radioactive radiation is corpuscular? | alpha
beta
helium nucleus; electron |
| 99. Define the concept of “Spin” and “Spin magnetism” | spin-->inherent rotation of a particle about its axis
spin magnetism--> due to spin (of charged particle), a magnetic field is produced, with a north and south pole
it is a vector quantity as it has direction and magnitude |
| 102. The magnetization vector M magnitude depends on the number of oriented spins, which are called ………… | excess spins?
(phase coherance??)
(or spin spin relaxation time??) |
| 113. What is the theoretical basis for radiotherapy? | radiobiology--> biological object's response to ionizing radiation
--> biological object's paradoxically BIG response to a relatively small amount of absorbed ionizing radiation |
| 104. What is the precession and Larmor frequency? | precession--> change in the orientation of the rotational axis of a rotating body (signals from precessing magnets can be received as radio signals)
larmor frequency--> spin precession frequency |
| 10. Name the consistent parts of the principal scheme of radiological studies | patient
radiologist
source of radiation/mechanical vibration
receiving device |
| 122. The concept of radiotherapeutic interval | the radiosensibility difference between normal tissue and abnormal tissue |
| 14. What is the physical nature of rays, used in Diagnostic Radiology? | electromagnetic
corpuscular
mechanical |
| 80. What are the causes of sound beam attenuation? | reflection
absorption
scattering |
| 4. When did W.K.Rentgen invent X-rays? | 1895 |
| 18. X-ray generation principal: | conversion of kinetic energy of electrons |
| 108. What are diagnostic criteria for MR study? | sensitivity is based on the difference of T1 and T2 relaxation constants of healthy and pathological tissues
depends to a lesser degree on proton density too |
| 126. Name the types of radiotherapy due to use with other treatment options | combined
complex
conjoined |
| 42. Which type of radioactive radiation is not used for diagnosis and why? | alpha
highly ionizing
non-penetrating |
| 78. What is the Pulse Repetition Period(PRP)? | time between the beginning of one pulse and the beginning of a second pulse |
| 38. What is the meaning of the term “radioactivity”? | ability of some chemical elements for spontaneous nuclear break-up
accompanied by specific radioactive radiation
+formation of a new chemical element |
| 33. How can we change signal to noise ratio using the contrast agents? | increase it by:
strengthening the signal
reducing the noise: by filtration and averaging |
| 119. What does the tissue radiosensitivity depend on? | metabolic activity
tissue oxygen partial pressure
mitotic activity |
| 75. What is the relation between incident and transmission angle? | If speed increases 1% as sound enters medium 2:
transmission angle ~1% > incident angle |
| 57. Name the end-information types, might be received on NM studies | numerical data (radiometry)
curves (NM radiography)
scannograms (NM scanning)
scintigrams (scintigraphy) |
| 62. What is the physical nature of sound? | mechanical oscillation of a medium (vibration)
represents mechanical energy |
| 92. What is the axial resolution of 2 cycle pulsed waive 3 MHz ultrasound (the propagation speed is 1,53 mm per microsecond) | Speed =F x wavelength (calculate wavelength use SPL equation
And then the axial resolution equation
=0.51 calculate and double check once more |
| 65. Define, what is the wave period | the time taken for one complete wave |
| 74. What is the relation between sound beam incident and reflection angle? | incident angle = reflected angle |
| 17. Is the X-Ray radiation uniform, homogenous? | can be homogenous and heterogenous
heterogenous after leaving the body |
| 109. What is the concept of MR Image Selected In-Vivo Spectroscopy (ISIS)? | chemical analysis of any sample |
| 58. What is the concept of thermography? | distant registration of spontaneous infrared radiation of investigated patient |
| 12. How can we decrease the noise? | filtration (dont show below certain amplitude)
averaging (average all waves) |
| 111. Which radiological modalities might be used for IR procedures guidance? | CT, MRI
Ultrasound
fluoroscopy |
| 69. What does the sound propagation speed depend on? | depends on the medium
(medium stiffness and density) |
| 31. How can we differentiate the tissues with the same degree of X-ray beam attenuation on the X-Ray image? | use contrast agents to produce artificial roentgenocontrast |
| 83. What is the main principle of ultrasound study? | echolocation |
| 94. Name the basic types of Ultrasound study | A mode- amplitude
B mode- brightness
M mode- motion |
