9. Other Radiographic Equipment Flashcards
used in rapid and serial exposures
Film and Cassette Changers
maximum of 6 per second
cut film changer
maximum of 12 per second
roll film changer
up to 1 exposure per second
Manual Cassette Changer
usually used in cerebral angiography where blood flow is slow
Manual Cassette Changer
3 to 5 cassettes held together in a holder by a large spring
Manual Cassette Changer
designed to accomplish rapid serialization of examination
Automatic Cassette Changer
up to 3 exposure per second
Automatic Cassette Changer
the photography of the image obtained on a fluoroscopic screen
Photofluoroscopy Unit
a permanent record is made through the fluoroscopic unit
Photofluoroscopy Unit
a specialized x-ray machine that uses a diagnostic technique in which a camera is used to record moving images of internal body structures produced through fluoroscopy
Cinefluoro Unit
Mobile Equipment
- Radiographic Units
* Fluoroscopic Units
Radiographic Unit
- Direct Power
- Battery Power
- Capacitor –Discharge
- High Frequency
can vary in the radiation output for a given exposure technique
Mobile x-ray units
In addition, care must be exercise in transporting and manipulating the mobile unit at the _____
patient’s bedside
usually used to aid the physician during surgery or angiographic studies
Fluoroscopic Units
Dedicated Units
- Chest
- Panoramic X-ray
- Bone Densitometry
- Mammography
is designed to image the thorax in the upright position
a dedicated chest unit
designed to image curved surfaces, typically the mandible of the teeth
Panoramic X-ray (Panorex)
also known as dual-energy x-ray absorptiometry (DXA or DEXA)
Bone Densitometer
enhanced form of x-ray technology that is used to measure bone loss
Bone Densitometer
specialized procedure using ionizing radiation to provide information on the condition of the skeletal bones
Bone Densitometer
the anatomic regions are scanned with two different x-ray energies to isolate bone from soft tissue attenuation
Bone Densitometer
absorb the x-ray photons and convert the energy proportionally to visible light, which is measured and sent to a computer for data analysis
DXA scintillation detectors
DXA or DEXA
dual-energy x-ray absorptiometry
indicates fracture risk
T-Score
may signify the need to evaluate patient for secondary cause of osteoporosis
Z-Score
2 Types of DXA Equipment
- Central device
* Peripheral device
is a specialized radiographic imaging procedure of the breast
Mammography
Mammography uses _____ kVp
low kVp (24 to 34 kVp)
In Mammography, the focal spot size used is
0.1 to 0.3 mm
exit port of Mammography
is made up of _____
beryllium
unique features include the ability to produce low kVp photons by using a tube anode constructed molybdenum and rhodium, a molybdenum or rhodium-composed tube filter, a beryllium port window, smaller focal spot sizes for improved resolution, compression for imaging a more uniform breast and the ability to magnify area of the breast
Dedicated Mammography Units
Mammography and Xeroradiography
•First attempted in ____
1920
Robert Egan demonstrated a successful mammographic technique year
Late 1950’s
year – xeroradiography developed by _____
1960’s,
Wolf and Ruzicka,
the making of radiographs by a dry, totally photoelectric process, using metal plates coated with a semiconductor, such as selenium
Xeroradiography
Purpose of Compression during Mammography
- Immobilizes breast
- Less thickness tissue
- Uniform thickness
- Reduces scatter radiation
- Position closer to image receptor
- Thinner tissue
made of tungsten (Z=74), molybdenum (Z=42) or a rhodium (Z=45) of Mammography
Target Composition
Atomic no. of Tungsten
74
Atomic no. of Molybdenum
42
Atomic no. of rhodium
45
mammography range of kVp use is from ____
20 to 35 kVp
Focal Spot of Mammography
circular or rectangular
Focal Spot sizes of Mammography
(0.6/0.3), (0.5/0.2), (0.4/0.1)
Filtration of Mammography – should be filtered with ____ of molybdenum or rhodium
30 to 60 microns
x-ray tube window of Mammography is made up of ____
beryllium or borosilicate
Atomic no. of beryllium
4
inherent filtration of Mammography=
0.1 mm Al equivalent
If molybdenum target is used, molybdenum filtration of __ micrometer is used
3
If rhodium target is used, rhodium filtration of __ micrometer is used
50
Common Combination of Target and Filter
- Molybdenum – molybdenum
- rhodium – rhodium
- Tungsten – rhodium
Grid ratio
4:1 or 5:1
Grid frequency of Mammography
30 lines per centimeter
Film types
- Film-Screen system
* Single emulsion film
is affixed to the tube head and is used to align the tube head with the patient and the X-ray film
The cylinder – (or cone) of Dental X-ray Unit
contains all the components necessary to generate x-rays
Tube of Dental X-ray Unit
Conventional Tomography
- Linear Tomography
- Multidirectional tomography
- Zonography
- Panoramic Tomography
designed to bring into focus only that anatomy lying in a plane of interest while blurring structures on either side of the plane
Tomography
is an imaging procedure using movement of the x-ray tube and image receptor in opposing directions to create images of structures in a focal plane by blurring the anatomy located above and below the plane of interest
Linear Tomography
the ____ the amount of blurring of the objects above and below, the more visible is the area of interest
greater (Linear Tomography)
increase exposure time is used
Linear Tomography
the x-ray tube and the image receptor moves in one direction
Linear Tomography
5 Basic Types of Tomographic Movements
- Linear
- Circular
- Elliptical
- Hypocycloidal
- Trispiral
is the imaging pivot point about which the x-ray and the image receptor move
Fulcrum
the fixed or pivot point that lies in the plane of interest during movement of the x-ray tube and IR
Pivot Point or Fulcrum
depending on the type of system, the ____ can be changed by moving the patient up and down or the pivot point is moved up or down
fulcrum
the plane in which the area of interest lies
Focal Plane
also known as object plane
Focal Plane
the structure here are sharper
Focal Plane
the angle movement
Tomographic Angle
determines the section image
Tomographic Angle
is the arc created during total movement of the x-ray tube
Tomographic Angle
the amount of blur is ____ related to tomographic angle
directly
the thickness of the section is ____ related to tomographic angle
inversely
thickness of tissue that will be imaged
Tomographic Layer
the thickness or width of the focal plane
sections
Multidirectional Tomography
- Circular
- Elliptical
- Hypocycloidal
- Trispiral
type of tomography used when imaging large zone of tissue
Zonography
usually used for chest examination using tomographic angles of 1 to 5 degrees
Zonography
first developed for fast dental surveys
Panoramic Tomography
the x-ray tube and the image receptor moves around the head
Panoramic Tomography
the beam and the receptor is receptor is slit collimated
Panoramic Tomography