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Radiology flashcards-Dr Shishir
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Radiology flashcards-Dr Shishir
Intro to radiology prt 1
Study
1
Question
 Early trials showed that it would require up to 15 minutes to expose a molar tooth, what helped reduce the exposure time to 1-2 minutes?
Answer
 improvements in the design of the x-ray tube
2
Question
what did Dr Kells use for his experiments, and what was the technique?
Answer
Dr. Kells used a fluoroscope for his experiments and adjusted the radiation until the bones were visible in the fluoroscope
3
Question
who is known as the 'Father of Dental Radiography?
Answer
Dr. Edmund Kells Jr
4
Question
why is Dr. Edmund Kells Jr known as the 'Father of Dental Radiography?
Answer
because he took the first dental radiograph of a living person in the United States.
5
Question
who presented the first dental skiagraphs in the USA?
Answer
Dr. WJ Morton
6
Question
the radiographs that Dr Otto Walkoff of Germany took are similar to which modern day radiographs?
Answer
bitewing radiographs
7
Question
how did Dr. Otto Walkoff of Germany took the first dental radiograph?
Answer
using a glass photographic plate wrapped in black paper
8
Question
the first recorded radiographic image was for?
Answer
Bertha Roentgen's hand
9
Question
why did Wilhelm Conrad call his new phenomenon the "x-ray"?
Answer
because 'x' is the universal symbol for the unknown, and ray because it traveled in a straight line
10
Question
Discovery of x-rays
Answer
November 8, 1895 - Wilhelm Conrad Roentgen discovered x-rays while researching on the effects of electrical discharge using a Crookes Hittorf tube.
11
Question
What were the X-ray tubes called in the General Electric company?
Answer
Coolidge tubes
12
Question
In 1920s, the X-ray exposures were reduced to how many seconds in duration?
Answer
4-10 seconds
13
Question
What led to injuries to both patients and clinicians due to high voltage current?
Answer
Uninsulated and unprotected wires
14
Question
What did General Electric introduce to overcome the problem of injuries caused by high voltage current?
Answer
Victor CDX shockproof dental X-ray unit
15
Question
When was the first machine-wrapped dental X-ray film packet introduced by Eastman Kodak company?
Answer
1919
16
Question
Who produced their own rubber film holder with a pocket for holding the dental X-ray film?
Answer
Dr. Kells
17
Question
In what year did Dr. John Marshall Section present a paper on the dangers of radiation at the Stomatology Section of the American Medical Association?
Answer
June 1897
18
Question
What did many early pioneers eventually develop from exposure to tremendous amounts of accumulated radiation?
Answer
Fatal cancers
19
Question
Who demonstrated the first panoramic radiograph in 1933?
Answer
Dr. H. Numata, Japan
20
Question
Who introduced digital imaging into the dental profession at the 1st European Congress of Dental and Maxillofacial Radiology in Geneva in 1987?
Answer
Dr. Francis Mouyen
21
Question
Who are the inventors of Cone Beam CT?
Answer
Daniele Godi and Giordano Ronca, Italy
22
Question
Who is a modern-day leader in dental radiography from the Netherlands?
Answer
Dr. Paul van der Stelt
23
Question
Who pioneered the application of digital imaging into dental practice from the USA?
Answer
Dr. Allan Farman
24
Question
What are the standards for digital imaging and communications in dentistry?
Answer
Digital Imaging and Communications in Medicine (DICOM) standards
Intro to radiology prt 2
Study
1
Question
what does Computerised tomography scan?
Answer
hard tissue
2
Question
which imaging technique provides multiplanar imaging without overlapping?
Answer
CT
3
Question
which extraoral radiographic technique is also known as waters view?
Answer
Paranasal sinuses view (PNS)
4
Question
which radiograph is used mainly for orthodontic purposes to capture a side view of the head and facial structures?
Answer
Lateral cephalogram
5
Question
in occlusal radiography, to get a view of the mandibular arch, where should the machine be placed?
Answer
90 degrees, below the oral cavity
6
Question
in occlusal radiography, to get a view of the maxillary arch, where should the machine be placed?
Answer
65 degrees, above the oral cavity
7
Question
evaluation of pulp treatment, is an indication for which type of radiographs?
Answer
IOPA
8
Question
Radiography
Answer
The technique involved in the production of various radiographic images.
9
Question
Radiology
Answer
The interpretation of the radiographic images.
10
Question
Radiographer
Answer
A technician who performs radiographic procedures.
11
Question
Radiologist
Answer
A doctor who specializes in interpreting and diagnosing radiographs.
12
Question
Oral radiology
Answer
Also known as maxillofacial radiology, it is the branch of radiology that focuses on imaging the oral and maxillofacial regions.
13
Question
what does Radiology use?
Answer
Ionizing radiation for diagnostic purposes. It involves the use of imaging techniques such as X-rays, CT scans, and fluoroscopy.
14
Question
Imaging
Answer
The process of producing visual representations of the interior of a body for clinical analysis and medical intervention. It uses both ionizing and non-ionizing radiation.
15
Question
Oral and Maxillofacial imaging Classification
Answer
Includes intraoral and extraoral imaging. It aids in diagnosing dental and oral health conditions.
16
Question
Intraoral imaging
Answer
Includes techniques that involve placing the imaging sensor or film inside the mouth to capture images of the teeth and surrounding structures.
17
Question
Intraoral periapical radiographs (IOPA)
Answer
Also known as periapical radiographs, they capture the entire tooth from the crown to the tip of the root and the supporting bone.
18
Question
Indications of IOPA:
Answer
Includes determining the status of periapical region in deciduous and young permanent teeth, evaluation of pulp treatment, detection of developmental anomalies, identification of pathology in primary teeth, evaluation of periodontal ligament and alveolar bone, diagnosis of traumatic injuries, etc.
19
Question
which intraoral radiographic technique captures the crowns of the upper and lower teeth in occlusion, provides a view of the interproximal areas for detecting caries and bone loss?
Answer
bitewing
20
Question
Occlusal radiograph
Answer
An intraoral radiographic technique that captures a broad view of the maxilla and mandible, providing information on the positioning of teeth and identifying pathology in the jaw.
21
Question
which Advanced intraoral imaging tool does not require chemical processing of films?
Answer
digital imaging sensors
22
Question
OPG (Orthopantomogram) is also known as?
Answer
panoramic radiograph.
23
Question
PA (Posteroanterior) view is mainly used for what?
Answer
mainly used for the post-traumatic examination of the skull.
24
Question
Magnetic resonance imaging (MRI)
Answer
An advanced imaging modality that uses a magnetic field and radio waves to produce detailed images of the body's organs and structures, particularly useful for soft tissue imaging.
25
Question
Ultrasound
Answer
An advanced imaging modality primarily used for imaging cervical lymph nodes in the neck region, utilizing non-ionizing radiation.
26
Question
Which type is imaging is used for salivary glands?
Answer
ultrasound
27
Question
CBCT stands for:
Answer
Cone beam computerized tomography
28
Question
CBCT Main advantage is that?
Answer
Significantly less radiation dose when compared to CT
29
Question
MRI Main advantage is:
Answer
imaging of soft tissues
30
Question
Ultrasound Mainly used for
Answer
imaging of cervical lymph nodes in the neck region
physics of X-rays
Study
1
Question
what is the Composition Of Matter?
Answer
up quarks, down quarks, and electrons.Â
2
Question
Up quarks and down quarks combine to form what?
Answer
neutrons and protons in atomic nuclei
3
Question
what do protons consist of? what is their charge?
Answer
two up quarks and one down quark. their charge is +1
4
Question
what do neutrons consist of? what is their charge?
Answer
one up quark and two down quarks. their charge is neutral
5
Question
what are the 2 forms of radiation?
Answer
1.Particulate radiation, and, 2.Electromagnetic radiation
6
Question
which radiation is generated when the velocity of an electrically charged particle is altered?
Answer
Electromagnetic radiation
7
Question
what are X-rays?
Answer
X-rays are wave packets of energy of electromagnetic radiation that originate at the atomic level (photons)
8
Question
how do X-rays travel in free space? and at what speed?
Answer
 X-rays travel in straight lines at a velocity of 3x10^8 m/s
9
Question
what is the inverse square law?
Answer
inverse square law: Intensity = 1/d^2 (intensity of an X-ray beam depends on the distance of the measuring device from the focal spot).
10
Question
X-rays Penetrating Power
Answer
No medium is required for propagation. The energy carried by X-rays can be attenuated by absorption and scattering by matter. Shorter wavelength X-rays have higher penetration capacity.
11
Question
which 2 x-ray interactions contribute to image formation?
Answer
photoelectric absorption and compton scattering
12
Question
why can x-rays cause subsequent biological damage in living tissue?
Answer
due to their ability to produce ionization
13
Question
how do x-rays produce a visual image?
Answer
by  affecting photographic emulsionÂ
14
Question
Bremsstrahlung (Braking Radiation)
Answer
The amount of deceleration and degree of deflection determine the amount of energy lost when an electron traveling from the anode nucleus very close to the nucleus. X-rays are produced due to this energy loss.
15
Question
in photoelectric absorption, what can the high energy ejected photoelectrons cause?
Answer
ionization interactions, which can damage living tissue
16
Question
percentage of coherent scattering
Answer
7%
17
Question
continuous Spectrum
Answer
The possible wide range of wavelengths of electromagnetic radiation.
18
Question
Characteristic Radiation
Answer
X-rays produced when an electron falls into a lower energy level in an atom.
19
Question
in photoelectric absorption, the high energy ejected photoelectrons act like what?
Answer
like the original high energy x-ray photon
20
Question
Coherent Scattering
Answer
A type of scattering in which the waves remain in phase during the interaction.
21
Question
the electrons bombarding the anode produce what?
Answer
heat majorly, and a small fraction is let out as X-rays
22
Question
percentage of photoelectric absorption
Answer
27%
23
Question
Photoelectric Absorption
Answer
The process by which the energy of an X-ray photon is totally absorbed by an atom, resulting in the ejection of an inner shell electron.
24
Question
percentage of compton scattering
Answer
57% (highest)
25
Question
Compton Scattering
Answer
A type of X-ray interaction in which a photon transfers some of its energy to an outer-shell electron, resulting in the photon being scattered at a lower energy.
26
Question
What are the 2 phenomena that produce x-rays at the anode?
Answer
1. Bremsstrahlung (braking radiation) contributes to the majority of X-ray production, and 2. Characteristic radiation contributes to only a small fraction of X-ray production.
X-ray machines
Study
1
Question
Circular collimator restricts the size of x-ray beam to how much?
Answer
7cm
2
Question
Collimator
Answer
a metallic barrier with an aperture in the middle used to restrict the size of the x-ray beam and the volume of tissue irradiatedÂ
3
Question
How is added filtration obtained?
Answer
by placing aluminum disc in the path of the x-ray beam
4
Question
Inherent filtration occurs inÂ
Answer
glass wall of the x-ray tube, and insulating oil
5
Question
Effects of low energy x-ray beams:
Answer
Do not contribute in image formation, and cause increased radiation exposure to a patient.
6
Question
What helps in removing the low energy x-ray beams?
Answer
Filtration
7
Question
more tube current
Answer
more photons
8
Question
more exposure time
Answer
more photons
9
Question
Which units are full wave rectified and have a constant potential?
Answer
Newer units
10
Question
which units are half wave rectified?
Answer
Older units
11
Question
Wave rectification
Answer
converts alternative current to a more stable current Â
12
Question
How much is the average tube voltage?
Answer
Intraoral and panoramic is around 60 and 90 kVp, and in CBCT around 90 to 120 kVp.
13
Question
Tube voltage
Answer
potential difference between anode and cathode
14
Question
How much is the average tube current?
Answer
About 10 mA
15
Question
Tube current
Answer
flow of electrons from the cathode filament across the tube to the anode.
16
Question
Which power supply reduces the voltage of the incoming alternating current (AC) to about 10 volts in the filament circuit?
Answer
filament transformer
17
Question
Which power supply provides a high voltage, required between the anode and cathode to give electrons sufficient energy?
Answer
autotransformer
18
Question
Why is copper is used for embedding tungsten in anode?
Answer
to dissipate heat generated during production of x-raysÂ
19
Question
Anode properties
Answer
 high atomic number (74), high melting point (3422°C), high thermal conductivity, low vapour pressure
20
Question
Anode function
Answer
converts kinetic energy of the electrons emitted from cathode to X-ray photonsÂ
21
Question
Anode is made up of
Answer
Tungsten embedded in copper stem
22
Question
the cathode filamentÂ
Answer
lies in focusing cup, it is negatively charged, made of Molybdenum, and is concave in shapeÂ
23
Question
Cathode is made up of
Answer
Tungsten in the form of coil about 2mm in diameter and 1 centimeter in length
24
Question
what is the source of electrons?
Answer
the cathode
25
Question
Main components of the control panel
Answer
The mains on/off switch and warning light, the time selector, film speed selector, patient size selector, kilovoltage selector , and the milliamperage switchÂ
26
Question
what is a disadvantage of the long-metallic rectangular spacer cone?
Answer
it can cause many errors.
27
Question
which beam indicating device is the best? and why?
Answer
The long-metallic rectangular spacer cone. due to it being of a similar size to the film, which help radiation not reach unnecessary parts of he patient.
28
Question
which beam indicating device is used the most?
Answer
The short-metallic open ended spacer cone
29
Question
what is the collimator made of?
Answer
lead
30
Question
what is the material used in filter of the tube head?
Answer
aluminum
X-ray dosage
Study
1
Question
Natural sources of radiation:
Answer
Cosmic radiation from the earth’s atmosphere, gamma radiation from the rocks and soil, ingestion of radioisotopes, and inhalation of radon gas and its decay products.
2
Question
Artificial sources of radiation:
Answer
Fallout from nuclear explosions, radioactive waste discharged from nuclear establishments, Medical and dental diagnostic radiation, and radiation from occupational exposure
3
Question
Dosimetry
Answer
Measurement of radiation.
4
Question
(D) in dosimetry stands for
Answer
Radiation absorbed dose, measured in Joules/Kg, and is called Gray (Gy)
5
Question
(HT) in dosimetry stands for
Answer
Equivalent dose, measured in Joules/Kg, and is called sievert (Sv)
6
Question
Equivalent dose (HT) calculation
Answer
Equivalent dose (HT) = radiation-absorbed dose (D) Ă— radiation weighting factor (WR) in a particular tissue
7
Question
radiation weighing factor in X-rays, gamma rays, and beta particles is:
Answer
WR=1
8
Question
radiation weighing factor in alpha particles is:
Answer
WR=20
9
Question
(E) in dosimetry stands forÂ
Answer
Effective dose, and is called Sievert (Sv)
10
Question
Effective dose (E) calculation
Answer
 Effective dose (E) = Σ Equivalent dose (HT) in each tissue × relevant tissue weighting factor (WT)
11
Question
 tissues that have a relevant tissue weighting factor of 0.12 are:
Answer
Bone marrow, breast, colon, stomach, and the lung.
12
Question
tissues that have a relevant tissue weighting factor of 0.01 are:
Answer
bone surface, brain, kidneys, skin, and the salivary glands
13
Question
tissues that have a relevant tissue weighting factor of 0.05 are:
Answer
Oesphagus
14
Question
tissues that have a relevant tissue weighting factor of 0.08 are:
Answer
Gonads
15
Question
tissues that have a relevant tissue weighting factor of 0.04 are:
Answer
Bladder, liver, and thyroid
16
Question
How to determine effective dose?
Answer
by using a tissue equivalent anthropomorphic phantom with dosimeters placed in the most radiosensitive regions.Â
17
Question
effective dose of Bitewing and periapical radiographs is:
Answer
0.0003-0.022 mSv
18
Question
effective dose of panoramic radiographs is:
Answer
0.0027-0.038 mSv
19
Question
effective dose of Dento-alveolar CBCT is:
Answer
0.01-0.67 mSv
20
Question
effective dose of Craniofacial CBCT is:
Answer
0.03-1.1 mSv
21
Question
Annual dose limits for classified workers( receive high levels of exposure to radiation):
Answer
20 mSv
22
Question
Annual dose limits for Non-classified workers( receive low levels of exposure to radiation):
Answer
6 mSv
23
Question
Annual dose limits for general public( everyone who is not receiving a radiation dose either as a patient or as a radiation worker, but who may be exposed inadvertently):
Answer
1 mSv
24
Question
What are dosimeters? and what are their forms?
Answer
Instruments used to measure radiation dose, found in the form of badges and rings
25
Question
what does TLD stand for?
Answer
Thermo luminescent dosimeter
26
Question
What substances does TLD contain?
Answer
calcium and lithium fluoride
27
Question
TLD principle
Answer
absorbs x-ray energy and stores it when the user is wearing it, then uses heat to generate light
28
Question
Where does the name ( thermo luminescent) come from in TLD?
Answer
After heating the material in the laboratory, the heating causes it to liberate light which is equal to the amount of x-ray it absorbed
29
Question
What does OSL stand for?
Answer
Optical stimulated luminescence dosimeter
30
Question
OSL principle
Answer
absorbs x-ray energy and stores it when the user is wearing it, then uses lasers to generate light