prelim Flashcards
(275 cards)
1
Q
The word tomography has as its root tomo, meaning
A
to cut, section, or layer
2
Q
The word tomography has as its root tomo, meaning to cut, section, or layer from the Greek meaning
A
tomos (a cutting)
3
Q
word “graphy” comes from the Greek word EANING which means “writing” or “drawing.”
A
“graphia,”
4
Q
In the case of CT, a sophisticated computerized method is used to obtain data and transform them intoWHAT
A
“cuts,” or cross-sectional slices of the human body.
4
Q
word “graphy” comes from the Greek word “graphia,” which means
A
“writing” or “drawing.”
5
Q
is the process of creating a cross-sectional tomographic plane of any part of the body.
A
Computed tomography (CT)
6
Q
Computed tomography (CT), is the process of creating WHAT
A
creating a cross-sectional tomographic plane of any part of the body.
6
Q
Unlike traditional X-ray images, which only capture a single plane, CT scans provide a more comprehensive, and what
A
3D view of internal structures.
7
Q
who Profession: Italian mathematician
A
ALLESANDRO VALLEBONA (1930s)
7
Q
who Profession: Austrian mathematician
A
JOHANN RADON (1917)
7
Q
who Proves that an image of 3 dimensional object could be produced from its mathematical projection.
A
JOHANN RADON (1917)
8
Q
who Developed Radon transform, a mathematical operator that plays a key role in various areas such as medical imaging (like CT scans), tomography, and even in signal processing.
A
JOHANN RADON (1917)
8
Q
a mathematical operator that plays a key role in various areas such as medical imaging (like CT scans), tomography, and even in signal processing.
A
Radon transform
9
Q
who
Proposed a method to represent a single slice of the body on the radiographic film (Topography)
A
ALLESANDRO VALLEBONA (1930s)
10
Q
ALLESANDRO VALLEBONA (1930s) Proposed a method to represent a single slice of the body on the radiographic film
A
Topography
10
Q
helped in the mathematical methods that enable the inversion of the Radon transform, which is essential for reconstructing images from the projections obtained in CT scans.
A
ALLESANDRO VALLEBONA (1930s)
10
Q
which is essential for reconstructing images from the projections obtained in CT scans.
A
inversion of the Radon transform
11
Q
He developed the mathematical foundation for tomographic imaging, which is the process of creating detailed images of internal structures by analyzing X-ray data taken from multiple angles
A
ALLAN CORMACK (1961)
11
Q
who Profession: South African-born physicist
A
ALLAN CORMACK (1961)
11
Q
He development of mathematical techniques for reconstructing cross-sectional images from X-ray data.
A
ALLAN CORMACK (1961)
12
Q
He was also involved in the development of other imaging technologies, such as positron emission tomography (PET).
A
WILLIAM OLDENDOR (1963)
12
Q
who Profession: Neurologist
A
WILLIAM OLDENDOR (1963)
12
Q
he’s work, involved using computers to process and reconstruct images from X-ray data, a breakthrough that laid the foundation for what would later become the modern CT scanner.
A
WILLIAM OLDENDOR (1963)
13
Q
who
Invented the first CT-Scan machine (1970) for WHAT at the Central Research Laboratory in England
A
EMI Ltd. (Electric and Musical Industries
13
who
Invented the first CT-Scan machine (1970) for EMI Ltd. (Electric and Musical Industries) at the Central Research Laboratory in England
GODFREY N. HOUNSFIELD (1970-71)
13
Both Hounsfield and Cormack share what
the 1979 Nobel Prize for medicine.
13
GODFREY N. HOUNSFIELD (1970-71)
Profession: Electrical engineer
Invented the first CT-Scan machine (1970) for EMI Ltd. (Electric and Musical Industries) at the ????
Central Research Laboratory in England
13
who Profession: Electrical engineer
GODFREY N. HOUNSFIELD (1970-71)
14
dedicated head scanner.
First-generation EMI CT unit
14
After CT was shown to be a useful clinical imaging modality, the first full-scale commercial unit, referred to as a WHAT, was installed in Atkinson Morley's Hospital in 1971.
brain tissue scanner
14
After CT was shown to be a useful clinical imaging modality, the first full-scale commercial unit, referred to as a brain tissue scanner, was installed in Atkinson Morley's Hospital in WHAT YEAR
1971
14
"The Father of CT Scan”
GODFREY N. HOUNSFIELD (1970-71)
14
BRAIN TISSUE SCANNER (1971)
After CT was shown to be a useful clinical imaging modality, the first full-scale commercial unit, referred to as a brain tissue scanner, was installed in WHERE in 1971.
Atkinson Morley's Hospital
15
The first CAT Scanner can produce a single sectional image in how many days
in 9 days
15
Early CT Scan machines are called what
Computed Axial Tomography (CAT) Scanners
15
who developed the first whole-body scanner, which greatly expanded the diagnostic capabilities of CT
Dr. Robert S. Ledley
15
The first CAT Scanner can produce a WHAT in 9 days
single sectional image
15
In what year, Dr. Robert S. Ledley of Georgetown University Medical Center, Washington, D.C., developed the first whole-body scanner, which greatly expanded the diagnostic capabilities of CT
1974
15
who Profession: American scientist
ROBERT LEDLEY (1974)
15
Early CT Scan machines are called Computed Axial Tomography (CAT) Scanners, because what
it can only produce Axial Images.
16
CT scanners have been categorized by WHAT, which is a reference to the level of technologic advancement of the tube and detector assembly.
generation
17
which is a reference to the level of technologic advancement of the tube and detector assembly
CT scanners have been categorized by generation
18
There wereHOW MANY recognized generations of CT scanners; however, newer scanners are no longer categorized by generation but by tube and detector movement.
4
18
There were four recognized generations of CT scanners; however, newer scanners are no longer categorized by generation but by what
by tube and detector movement.
19
other names of ct scanners
Computed Axial Tomography (CAT)
Computed Transaxial Tomography (CTAT)
Computed Reconstruction Tomography (CRT)
Digital Axial Tomography (DAT)
Body Section Roentgenography
19
CT SCANNER
Consists of an WHAT that both moving synchronously in a translate or rotate mode or a combination of both.
Consists of an x-ray source emitting finely collimated x-ray beam and a single detector
19
Consists of an x-ray source emitting finely collimated x-ray beam and a single detector both moving synchronously in a translate or rotate mode or a combination of both.
CT SCANNER
19
CT SCANNER
Consists of an x-ray source emitting finely collimated x-ray beam and a single detector both moving WHAT in a translate or rotate mode or a combination of both.
synchronously
19
CT SCANNER
Consists of an x-ray source emitting finely collimated x-ray beam and a single detector both moving synchronously in a WHAT
translate or rotate mode or a combination of both.
19
MAIN PARTS OF A CT SCANNER
Gantry Assembly
Patient Table/Couch
X-ray Tube
Detectors
Computer
Display Console
Speakers
Mic
20
is a vertical plane, running from the front to the back of the body. It divides the body into left and right sections.
sagittal plane
21
Also known as the frontal plane, is another important anatomical plane used to describe the orientation of the body. It divides the body into front (anterior) and back (posterior) portions.
CORONAL PLANE
21
also known as the transverse plane, is the third major anatomical plane. It divides the body into upper (superior) and lower (inferior) parts, running horizontally across the body. It is perpendicular to both the sagittal and coronal planes.
axial plane
21
The most prominent part of a CT scanner
gantry
21
a circular, rotating frame with an X-ray tube mounted on one side and a detector on the opposite side.
gantry
21
GANTRY ASSEMBLY
aka
"doughnut shape equipment"
21
This tube generates the X-rays that pass through the body and are detected by sensors on the other side.
gantry assembly
21
It is the opening in the gantry of a CT scanner through which the patient is positioned for scanning. The gantry itself is the rotating frame that holds the X-ray tube and detectors.
GANTRY APERTURE
22
is the central circular opening that allows the patient to pass through it, usually lying on a motorized table that moves them through the scanner.
aperture
22
The size of the aperture varies depending on WHAT
depending on the model of the CT scanner, but it generally needs to be large enough to accommodate the body part being imaged.
22
how many inches or cm in gantry aperture in general diagnostic
50-80 cm (20"-34")
22
how many inches or cm in gantry aperture in dedicated machines in radtherapy
100 cm (39.3")
22
limits tilt of gantry aperture
Limits: Tilt (+/- 30 deg)
22
gantry aperture considerations;
size, patient comfort and scan quality
22
A larger aperture can accommodate larger body parts or patients, while a smaller one might be ideal for WHAT
for high-resolution scans of specific areas (such as the brain or heart).
23
T OR F. A larger aperture may affect the quality of the scan, so precision in aperture size is important for ensuring accurate imaging.
TRUE
23
T OR F. A smaller aperture may affect the quality of the scan, so precision in aperture size is important for ensuring accurate imaging.
FALSE
23
A larger aperture may affect the quality of the scan, so precision in aperture size is important for WHAT
ensuring accurate imaging.
24
Refers to the X-ray tube used in a CT scanner (computed tomography scanner).
CT TUBE
24
It is a critical component that generates X-rays, which are used to create cross-sectional images of the body.
s-sectional images of the body.
CT TUBE .
24
ct tube For 80x80 matrix display:
- Stationary anode with 2mmx16mm focal spot.
- 120 KVp, 30mA.
24
CT tube For 512x512 matrix display:
- Rotating anode with 0.6mmx1.2mm focal spot.
- KVp selectable (80, 120, 140), 1000mA.
25
how many units of thermal capacity
0.5-5 million Heat Units thermal capacity.
25
is an essential component of a CT scanner.
CT scan detector
25
It helps capture the X-ray data that is used to create cross-sectional images (slices) of the body.
CT scan detector
25
works in tandem with an X-ray source to measure the X-rays that pass through the body.
CT scan detector
25
The detector works in tandem with an X-ray source to WHAT
to measure the X-rays that pass through the body.
26
The detector consists of WHAT
an array of scintillators or photodiodes that convert the X-rays(photons) into electrical(digital) signals
26
The detector consists of an array of scintillators or photodiodes that convert the X-rays(photons) into electrical(digital) signals. These signals are then sent to WHAT
a computer.
27
Source to Detector Distance:
- 44" (110cm)
- 20-40" (50-100cm)
28
DETECTOR PARAMETERS
- Capture Efficiency
- Absorption Efficiency
- Conversion Efficiency
- Detector Dose Efficiency
- Stability
- Response Time
- The Dynamic Range
28
Efficiency to receive photons. Controlled by detector size and interspacing.
Capture Efficiency
28
Efficiency to convert photons to light or ions. Controlled by detector material, size and thickness.
Absorption Efficiency
28
Efficiency to Convert light or ions to digital signal.
Conversion Efficiency
29
Overall efficiency (DDE= CapE + AE + ConE)
Detector Dose Efficiency
29
Detector Dose Efficiency
Overall efficiency (DDE= CapE + AE + ConE)
29
the ability to maintain in a quality calibrated state. Fixed detector arrays are the most stable.
Stability
29
the speed of the detector to react/recognize incoming xray photon and recover for the next input.
Response Time
30
describes the range of x-ray intensities a detector can differentiate.
The Dynamic Range
30
provides the discrimination between small differences in x-ray attenuation.
A high dynamic range
30
TYPES OF DETECTORS:
- Solid State Detectors
-- Gas-Filled Detectors
30
Consist of Scintillation Crystals (materials capable of releasing light photons when struct by xray) and Photomultiplier tube.
- Solid State Detector
30
Detector Dose Efficiency = >50%
- Solid State Detector
30
Near 100% Absorption Efficiency
- Solid State Detector
31
Cannot be packed tightly (interspacing), Capture Efficiency is around 50%.
- Solid State Detector
31
Uses Scintillation materials like WHAT
Sodium lodide [Nal] (100% AE, but has phosphorescence, decrease in Response Time.)
31
Detector Dose Efficiency = WHAT
>50%
31
Near how any percent Absorption Efficiency in solid state detectors
100%
31
in solid state detector,
Cannot be packed tightly (interspacing), Capture Efficiency is around how many percent
around 50%.
31
SOLID STATE DETECTOR
Consist of what
Scintillation Crystals (materials capable of releasing light photons when struct by xray) and Photomultiplier tube.
31
Modern solid state detectors uses
- Calcium Flouride [CaF2]
- Bismuth Germinate [Bi4Ge3012]
- Cesium lodide [Csl]
- Gadolinium Ceramics [Gd]
- Calcium Tungstate [CaWO4].
31
Modern solid state detectors uses Calcium Flouride [CaF2], Bismuth Germinate [Bi4Ge3012], Cesium lodide [Csl], Gadolinium Ceramics [Gd], and Calcium Tungstate [CaWO4]. HOW MANY PERCENT Absoption Efficiency, has no afterglow, increase in Response Time.
90%
31
Modern solid state detectors uses Calcium Flouride [CaF2], Bismuth Germinate [Bi4Ge3012], Cesium lodide [Csl], Gadolinium Ceramics [Gd], and Calcium Tungstate [CaWO4]. 90% Absoption Efficiency, has WHAT
has no afterglow, increase in Response Time.
31
Consist of pressurized Gas-Filled (Inert/Noble Gases) lonization chambers and tungsten electrode plate (1.5mm apart).
gas filled detectors
32
, any of the elements in Group 18 of the periodic table. In order of increasing atomic number they are: helium, neon, argon, krypton, xenon, and radon
Inert gas or noble gas
33
GAS-FILLED DETECTOR
Consist of WHAT
Consist of pressurized Gas-Filled (Inert/Noble Gases) lonization chambers and tungsten electrode plate (1.5mm apart).
34
lnert gas or noble gas, any of the elements in Group 18 of the periodic table. In order of increasing atomic number they are:
helium, neon, argon, krypton, xenon, and radon.
34
how many percent of absoprtion of efficiency in gas filled detector
60-90%
34
Cannot be used in 4,5,7th and Helical Scanners
GAS-FILLED DETECTOR
34
Can be packed tightly, Capture Efficiency >90%.
GAS-FILLED DETECTOR
34
Fast Response Time
GAS-FILLED DETECTOR
34
Highly Directional and must be set in a fixed position oriented to the xray source.
GAS-FILLED DETECTOR
35
is a device used to control and shape the X-ray beam as it exits the X-ray tube. Its primary purpose is to ensure that only the necessary portion of the body is exposed to radiation, which improves image quality and reduces unnecessary radiation exposure to the patient.
collimator in a CT scanner
36
Its primary purpose is to ensure that only the necessary portion of the body is exposed to radiation, which improves image quality and reduces unnecessary radiation exposure to the patient.
collimator in a CT scanner
37
KEY FUNCTIONS OF A COLLIMATOR:
- Beam Shaping
- Reducing Scatter Radiation
- Minimizing Radiation Dose
- Controlling Slice Thickness
37
TYPES OF COLLIMATORS:
- Pre-Patient Collimator
- Post-Patient Collimator
37
he collimator shapes the X-ray beam to match the area of the body being scanned. This ensures that the X-rays are directed only to the specific region of interest, helping to minimize exposure to surrounding tissues.
Beam Shaping
37
Beam Shaping: The collimator shapes the X-ray beam to match the area of the body being scanned. This ensures that the X-rays are directed only to the specific region of interest, helping to WHAT .
minimize exposure to surrounding tissues.
37
Reducing Scatter Radiation: Collimators help reduce scatter radiation, which is unwanted radiation that can bounce off tissues and create noise in the image. This improves WHAT
improves the clarity and contrast of the final image.
37
Controlling Slice Thickness: In some CT scanners, collimators also influence the thickness of the image slices. This is particularly important in multi-slice CT scanners where thin slices are often required for WHAT
detailed imaging.
37
Located between the X-ray tube and the patient, this collimator helps to shape the X-ray beam before it interacts with the body. It is crucial for controlling the size and shape of the beam to cover only the necessary area.
PRE-PATIENT COLLIMATOR
37
Located after the patient, this collimator controls the X-rays that pass through the body and reach the detector. It helps eliminate any scattered X-rays that might contribute to noise or artifacts in the image
POST-PATIENT COLLIMATOR
37
refer to specific movements of either the X-ray tube or the detector during the scan process
"translate" and "rotate"
38
This refers to the circular movement of the X-ray tube and the detector around the patient's body. The tube and detector rotate around the body along the X-axis (horizontal axis).
ROTATE
38
This allows the scanner to take multiple X-ray images from different angles, which are then used to create detailed cross-sectional images (slices) of the body.
ROTATE
38
This refers to the linear movement of the X-ray tube and detector along the body. In a CT scanner, translation often occurs when the patient moves through the scanner during the scan. This movement is typically along the Z-axis (the axis running vertically, through the patient's body)
TRANSLATE
38
in PATIENT COUCH/TABLE
General Radiography
Curved
38
in PATIENT COUCH/TABLE
Radiation therapy
Flat
38
PATIENT COUCH/TABLE
Low Z material
Carbon Fiber Graphite
39
PATIENT COUCH/TABLE
Low Z material (Carbon Fiber Graphite) Weight Limit (manufacturer's specs) Typical weight capacity ranging from WHAT
ranging from 150 kg (330 lbs) to 250 kg (550 lbs)
40
COMPUTER
The CT scan computer (often referred to as WHAT
CT scanner's computer system or CT imaging workstation
40
is the core component responsible for controlling the entire CT scanning process, as well as processing, reconstructing, and displaying the images produced by the scanner.
CT scan computer (often referred to as the CT scanner's computer system or CT imaging workstation)
40
KEY COMPONENTS: OF COMPUTER:
- Central Processor (CPU)
- Data Acquisition System (DAS)
- Image Reconstruction Unit
- Display Workstation
- Storage System
41
FUNCTIONS OF THE CT SCAN COMPUTER:
- Control of the CT Scanner:
- Data Acquisition
- Image Reconstructio
- Image Display
- Post-Processing
- Data Storage
- Radiologist Workstations
- Patient Management and Reporting
41
Manages the processing power for reconstruction algorithms and system control.
Central Processor (CPU)
41
Receives raw data from the detectors and transmits it to the processor.
Data Acquisition System (DAS)
41
Uses mathematical algorithms to convert raw data into usable images.
Image Reconstruction Unit
41
Displays images for radiologists, with features for image manipulation and analysis.
Display Workstation
42
Stores images and data securely, often in a PACS or cloud-based system.
Storage System
43
rotates around the patient and the detectors collect the transmitted X-rays, the computer receives this data in the form of raw data (also called projections). These data points represent measurements of the X-rays that passed through different parts of the body.
DATA ACQUISITION
44
DATA ACQUISITION
As the X-ray tube rotates around the patient and the detectors collect the transmitted X-rays, the computer receives this data in the form of WHAT .
form of raw data (also called projections).
44
The computer also monitors the detector elements (which can be made of scintillator crystals or solid-state detectors) to ensure they are functioning correctly during the scan.
data acquisition
44
These data points represent measurements of the X-rays that passed through different parts of the body.
DATA ACQUISITION
45
1ST GENERATION CT SCAN
Head only
Rotate-Translate
Xray Collimator: 3mmx26mm
Scan Arc: 180deg
4.5-5min scan per section.
single ray pencil beam
single detector (Solid State: Nal-PM tube)
Display: Matrix (80x80), Voxel (3mmx3mmx13mm)
Pencil Beam - Benchtop
Pencil Beam - Rotating CT
45
3RD GENERATION CT SCAN
Whole Body with dynamic scanning
Single Projection exposure
Scan Arc: Selectable (220 deg or 360 deg)
2-10 sec scanning time per section
Fan shaped xray beam (wide)
250-750 detectors (Curvilinear) of Solid State or Gas- Filled. Prone to Ring Artifacts.
Display: Matrix (selectable up to 526x526), Voxel (selectable)
45
2ND GENERATION CT SCAN
Whole Body
Rotate-Translate
Xray Collimator: 3mmx13mm (30septums)
Scan Arc: 180deg
10-90 sec per section scanning time
Fan shaped xray beam (narrow)
30 detectors (linear) of Solid State or Gas-Filled Display: Matrix (Selectable up to 320x320), Voxel(Selectable)
45
4TH GENERATION CT SCAN
Whole body with dynamic scanning
Single Projection Exposure
Scan Arc: Selectable (180-360+deg)
2-10 sec scanning time per section
Fan shaped xray beam (wide)
600-2000 detectors (fixed circular) Solid State.
Display: Matrix (Selectable up to 512x512), Voxel (Selectable)
45
This 5th generation is uses a flying electron beam, steered electromagnetically and to hit one of the anode strips that encircle the patient. No moving parts, therefore very fast (about how many ms)
about 50 ms
45
other term 5TH GENERATION CT SCAN
Electron-beam Computed Tomography
45
It developed specifically for cardiac tomographic imaging
5th generation
45
is uses a flying electron beam, steered electromagnetically and to hit one of the anode strips that encircle the patient. No moving parts, therefore very fast (about 50 ms).
5th generation
45
The advantage of this 5th generation ct scan are WHAT
extremely fast and capable of imaging the beating heart.
45
produces a focused electron beam that generates a rotating x-ray fan beam after being steered along tungsten target
Electron Gun-
45
Whole Body with dynamic scanning
Multiple Projection Exposure
Scan Arc: 360 deg
Scanning time as a function of Pitch Ratio
Fan shape xray beam (wide)
600-2000 detectors (fixed circular) Solid State
Display: Matrix (Selectable up to 512x512), Voxel (Selectable)
Excels in 3D Multi-planar Reformation (MPR)
Uses slip ring technology
6TH GENERATION CT SCAN
45
other term 6TH GENERATION CT SCAN
Helical/Spiral CT Scan
45
The disadvantage of this 5th generation ct scan are WHAT
high costs and difficult to calibrate, therefore it is not clinically used
45
other term 7TH GENERATION CT SCAN
64/128/254 Multi-Slice CT
45
7TH GENERATION CT SCAN
Whole Body with dynamic scanning
Multiple Projection Exposure
Scan Arc: 360 deg
Multiple Detector Array
Fan shape xray beam (wide)
Fast scanning CT Scan
Can produce High Definition topography
Excels MPR and 3D reconstruction
46
TYPES OF SCANNER
Scanning pencil beam
Scanning fan beam
Full fan-beam with rotating detector*
Full fan-beam with stationary detector*
Electron-beam CT (EBCT)
Spiral CT*
Multislice CT*
47
The most basic form of CT scanner
SINGLE-SLICE CT SCANNER
47
Takes one slice (cross-sectional image) of the body at a time
SINGLE-SLICE CT SCANNER
48
Less commonly used today due to advancements in multi-slice technology.
SINGLE-SLICE CT SCANNER
48
The X-ray tube and detectors rotate around the body to capture a series of 2D images
SINGLE-SLICE CT SCANNER
49
*Basic, older technology for general use
SINGLE-SLICE CT SCANNER
49
Basic diagnostics, such as detecting fractures or simple tumors.
SINGLE-SLICE CT SCANNER
49
Faster than single-slice scanners and provides higher-resolution images.
MULTI-SLICE CT SCANNER
50
This is a more advanced CT scanner that uses multiple rows of detectors (usually 16, 32, 64, or more) to capture multiple slices at once
MULTI-SLICE CT SCANNER
50
Highly beneficial in emergency situations.
SPIRAL (HELICAL) CT SCANNER
51
Can produce 3D images by stacking the multiple slices.
MULTI-SLICE CT SCANNER
51
More detailed diagnostic imaging.
MULTI-SLICE CT SCANNER
51
Used in various fields, including oncology, cardiology, and trauma care.
MULTI-SLICE CT SCANNER
52
Faster and better for imaging complex areas such as the be vessels
MULTI-SLICE CT SCANNER
52
Advanced, faster, and better resolution for complex imaging (e.g., organs, blood vessels)
MULTI-SLICE CT SCANNER
53
The X-ray tube continuously rotates around the patient while they move through the scanner in a spiral motion.
SPIRAL (HELICAL) CT SCANNER
53
Frequently used for chest, abdominal, and brain imaging
SPIRAL (HELICAL) CT SCANNER
53
Produces continuous images without interruption and allows for a more efficient scan.
SPIRAL (HELICAL) CT SCANNER
54
Primarily used in dental, ENT (ear, nose, and throat), and orthopedic imaging
CONE-BEAM CT SCANNER
54
Used to detect conditions like pulmonary embolisms, strokes and certain types of cancers
SPIRAL (HELICAL) CT SCANNER
54
*Quick imaging of the chest. abdomen, and pelvis: diagnosing pulmonary embolism, appendicitis. and cancer staging
SPIRAL (HELICAL) CT SCANNER
54
The scanner uses a cone-shaped X-ray beam to capture detailed 3D images of the body particularly the head and neck region.
CONE-BEAM CT SCANNER
55
Dental and maxillofacial imaging. planning dental implants, and evaluating head and neck conditions.
CONE-BEAM CT SCANNER
56
Less radiation exposure compared to traditional CT in some cases
CONE-BEAM CT SCANNER
56
A specialized CT scanner that focuses on imaging the heart and blood vessels
CARDIAC CT SCANNER
56
Often used to assess coronary artery disease, heart function, and abnormalities in the heart's structures.
CARDIAC CT SCANNER
56
Dental and orthodontic imaging, such as evaluating the jaw, teeth, and bones of the face.
CONE-BEAM CT SCANNER
56
Used for sinus, ear, and nasal cavity scans
CONE-BEAM CT SCANNER
56
This technology allows for more precise imaging of soft tissues, blood vessels, and organs, and can be used to distinguish between different types of stones (like kidney stones).
DUAL-ENERGY CT SCANNER
56
The PET scan shows WHAT(how tissues and organs are functioning), while the CT scan provides detailed anatomical images.
metabolic activity
56
Planning heart surgery or evaluating heart function
CARDIAC CT SCANNER
56
Designed for imaging the heart and coronary arteries with high-speed scanning for detailed heart and blood vessel analysis
CARDIAC CT SCANNER
56
Assessing coronary artery disease (such as blockages or narrowing of arteries).
CARDIAC CT SCANNER
56
Used to visualize blood vessels for condition like aneurysms
CARDIAC CT SCANNER
56
Differentiating tissue types, detecting cancer, assessing kidney stones, gout, and vascular conditions
DUAL-ENERGY CT SCANNER
56
Uses two different X-ray energy levels to create images, which are then analyzed to differentiate between materials based on their atomic composition.
DUAL-ENERGY CT SCANNER
56
Helpful for identifying conditions like gout or kidney stones distinguish different types of tissue or stones based in their material
DUAL-ENERGY CT SCANNER
56
is particularly useful for detecting cancers, assessing heart function, and evaluating brain disorders
PET-CT
56
Typically used in situations where transport to a full CT room is not feasible
PORTABLE CT SCANNER
56
Used for advanced imaging of tissues, particularly in oncology to differentiate between tumors and healthy tissue
DUAL-ENERGY CT SCANNER
56
A smaller, more compact version of a CT scanner that can be moved to different locations, such as in emergency rooms or intensive care units (ICUs).
PORTABLE CT SCANNER
57
Combines Positron Emission Tomography (PET) and CT scanning technology in a single machine.
SINGLE-SLICE CT SCANNER
57
Mostly used in oncology to locate and evaluate cancer cells.
SINGLE-SLICE CT SCANNER
57
what odality The PET scan shows metabolic activity (how tissues and organs are functioning), while the CT scan provides detailed anatomical images.
SINGLE-SLICE CT SCANNER
57
Used in evaluating heart disease and brain disorders (like Alzheimer's)
SINGLE-SLICE CT SCANNER
57
*Cancer detection and monitoring.evaluating brain conditions (like Alzheimer's), cardiac assessments, and tracking cancer treatment effectiveness
SINGLE-SLICE CT SCANNER
57
*Provides high-precision imaging for real-time guidance. Minimizes the need for open surgery by enabling minimally invasive procedures.
INTERVENTIONAL CT SCANNER
57
Used in a procedure where CT scans guide the doctor during surgery or a minimally invasive procedure
INTERVENTIONAL CT SCANNER
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Used during procedures like biopsies, drain placements, or the removal of tumors
INTERVENTIONAL CT SCANNER
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T or F. Effect on Image lower kvp provides better penetration and can result in reduced patient dose but may decrease soft tissue contrast.
false, hgher kvp
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t or f. Effect on Image Higher kVp provides better penetration and can result in reduced patient dose but may decrease soft tissue contrast.
t
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Provides real-time imaging to help doctors make precise decisions during interventions, such as biopsies or the insertion of stents
INTERVENTIONAL CT SCANNER
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Common in emergency settings for trauma care
INTERVENTIONAL CT SCANNER
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Used for critically ill patients who cannot be moved easily, providing faster imaging in emergency or critical care settings.
PORTABLE CT SCANNER
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results in higher noise and grainier images reduces radiation down but may compromise image quality, particularly in large patients or in detailed imaging
Lower mAs
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This are vital in emergency care, offering quick, on-site diagnostic capabilities that improve patient outcomes by enabling timely decision-making and treatment.
PORTABLE CT SCANNER
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increases contrast for soft tissue imaging May be useful for imaging the chest or abdomen, where distinguishing soft tissues is important
Lower kVp
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Less powerful than traditional CT scanners but still offers useful diagnostic capabilities.
PORTABLE CT SCANNER
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controls the energy level of the X-ray beam, determining its penetration ability
kVp
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Typical Range of kVp.
Typical Range: 70-140 kVp.
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improves the ability of the X-rays to penetrate dense structures (e.g.. bones). Reduces contrast in soft tissues
Higher kVp
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It determines the total radiation dose delivered to the patient and affects image quality
mAs
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is the product of the X-ray tube current (mA) and the exposure time (seconds).
mAs
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reduces noise and increases image quality by improving signal intensity increases radiation dose
Higher mAs
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Typical Range of mAs
Typical Range 100-400 mAs, depending on the body part and size
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t or f . Effect on Image: Higher mAs improves image clarity and jncreases radiation dose
t
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offer higher resolution and better detail especially useful for detecting small lesions, fine anatomical structures, or in 3D reconstructions (eg.. 0.5 mm to 1 mm)
Thinner Slices
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how many mm is often used for higher resolution imaging,
1 mm
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Refers to the thickness of each individual cross-sectional image (or "slice") obtained during the scan.
SLICE THICKNESS
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Common slice thicknesses range from what
0.5 mm to 5 mm
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t or f. Effect on Image: lower mAs improves image clarity and jncreases radiation dose
f, higher mas
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particularly for detailed views like in neurology or vascular imaging how many mm slices may be used in routine chest or abdominal scans, where a lower resolution might suffice
5 mm
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what slices They may help reduce the overall radiation exposure
Thicker Slices
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ie the number of line pairs that can be imaged as separate structures within one centimeter
line pairs per centimeter (Ip/cm)
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Pitch Ratio:
PITCH = Couch movement each 360 Beam width
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t or f. In CT the technologist has access to numerous scan parameters that can have a dramatic effect on image quality.
t
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The scan parameters that affect spatial resolution include what
focal spot size, slice thickness, display FOV, matrix, and reconstruction algorithm.
60
Matrix Size:
- Total number of pixel displaved (DRT).
rows and columns of pixels displayed on a digital image
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is a product of the pixel area and slice thickness
The voxel volume
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Resolution is measured in WHAT ie the number of line pairs that can be imaged as separate structures within one centimeter
line pairs per centimeter (Ip/cm)
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is the measure of how far apart two objects must be before they can be seen as separate details in the image. For two objects to be seen as separate the detectors must be able to identify a gap between them.
Resolution
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Voxel:
a volume element
The tissue volume
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the scan parameters that affect contrast resolution are what
slice thickness, reconstruction algorithm, image display, and x-ray beam energy.
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A single square, or picture element, within the matrix is called a WHAT
a pixel.
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Currently, tissues with density differences of how many % can be distinguished with CT.
less than 0.5%
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HIGH PITCH ( FAST TABLE MOVEMENT)
Faster scan time:
Lower radiation dose
Lower image quality
Used for: Faster imaging of less critical areas, where high image resolution is less important (eg routine screenings or large organs like the abdomen)
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is the most significant geometric factor that contributes to spatial resolution.
The detector aperture width
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are often used for more routine imaging when fine detail is less critical, such as general surveys of large areas of the body (eg.. 3 mm to 5 mm)
Thicker Slices
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The four main factors contributing to image quality are
spatial resolution, contrast resolution, noise, and artifacts.
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describes the amount of blurring in an i mage.
Spatial resolution
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Pixel:
a picture element
Each cell of information
Two-dimensional
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The digital image is an array of numbers arranged in a grid of rows and columns called a WHAT
matrix
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Image graininess from quantum mottle and statistical fluctuation in the information detected
NOISE
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is the ability to differentiate between small differences in density within the image.
Contrast resolution
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t or f. The size of the patient and the detector sensitivity doesn't have a direct effect on contrast resolution.
false, it also has
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what slices they increase the radiation dose and the amount of data to be processed which might be a consideration in some cases
Thinner Slices
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The slice thickness gives the pixel an added dimension called the WHAT
volume element, or voxel
61
LOW PITCH ( SLOW TABLE MOVEMENT)
Longer scan time
Higher radiation dose:
Higher image quality
Used for: Detailed imaging of small or critical areas, such as the brain, coronary arteries, or areas needing high precision.
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t or f. The size of the patient and the detector sensitivity also have a direct effect on contrast resolution.
t
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The relationship between patient couch movement and x-ray beam width
PITCH
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Noise in a CT image primarily affects the what
contrast resolution
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Standard normal noise values are how many % of the image Ruled out by water phantom test.
3-5%
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t or f. As noise decreases, contrast resolution increases.
f
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gives an image a grainy quality or a mottled appearance.
Noise
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t or f. As noise increases, contrast resolution decreases.
t
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Among the scan parameters that influence noise are what
matrix size, slice thickness, x-ray beam energy, and reconstruction algorithm.
64
The anatomy displayed is often referred to as the what
display FOV
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The image that appears on the CRT depends on the scan diameter also called what
scan FOV
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Slice thickness is usually dictated by image protocol. As in tomography, the thinner the slice thickness, the better the image recorded detail. Thin-section CT scans, often referred to as WHAT, are used to better demonstrate structures
high resolution scans
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types of artifacts:
Motion Artifacts
Metal Artifacts
Beam Hardening
Partial Volume Artifacts
Aliasing Artifacts
Ring Artifacts
Noise
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are usually preselected by the computer as part of the scan program, but they can be altered by the technologist
Scan times
64
is usually required to compensate for large body size.
An increase in milliampere-seconds (mAs)
64
can arise from various factors, often related to the equipment, patient motion, or the way data is processed.
Artifact
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t or f. Scattered radiation and patient size also doesn't have any contribute to the noise of an image..
f
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t or f. Scattered radiation and patient size also contribute to the noise of an image.
t
64
Image quality factors under technologist control include what
slice thickness, scan time, scan diameter, and patient factors.
64
refers to any distortion or error in the image that doesn't represent the true anatomy or pathology of the patient.
Artifact
