Control Console/Ribs Flashcards
What is the joint called where the head of the rib articulates with the vertebral bodies?
Costovertebral joint
Area between ribs
Intercostal space
What is the joint called where the tubercles articulate with the T-spine transverse processes?
Costotransverse joints
When the patient inhales, how do the ribs lay?
Horizontally
When the patient exhales, how do the ribs lay?
Obliqued
How many inches above the shoulders should the IR be?
1.5”
How are lower ribs always done?
AP
For lower ribs, where is the lower edge of the IR at?
Level of iliac crests
For PA obliques, which side is away from the IR?
Affected anterior side
For AP obliques, which side is closer to the IR?
Affected side
What does high-voltage current determine?
Strength of x-rays
What does low voltage current determine?
Number of x-rays
What are the four things that make up the control console?
kVp
mA
exposure time
line compensation
Adjusts the incoming alternating current voltage to a steady 220 V
Line voltage compensator
What are 3 types of losses of power in transformers?
Copper
Eddy current
Hysteresis
Function is the kVp selection
Autotransformer
Primary side of high-voltage
Autotransformer
Single coil of insulated wire wound around a large iron core. At intervals along the core called bare points, are major kVp and minor kVp
Construction of autotransformer
Single coil serves as both primary and secondary coil; Operates on self induction
Autotransformer
What controls the filament current; or the mA
Rheostat
This is what is used in modern equipment for mA selectors
Saturable reactor
Always located on the primary side; except for mAs timers
Exposure timers
Separate from other main circuits; action is to “make” or “break” the high-voltage across the tube
Exposure timers
Modern type of timer
Electronic timers
Most sophisticated and the most accurate type of timer
Electronic timer
Function is to measure the quantity of radiation reaching the film and automatically terminate the exposure when sufficient radiation to provide the required film density has reached the film
AEC (phototimers)
With AEC, can you pick out a mAs?
No
What are the two types of AEC’s?
Phototimers
Ionization timers
AEC that is now used in modern equipment
Ionization timers
Based on an ionization chamber which contains a volume of air between two metal electrodes; Located between the patient and the IR
Ionization timers
These chambers have to be calibrated when they’re installed by service engineers to adjust correct densities
Ionization timers
Why is the back up time for AECs important?
Ask as a safety factor
What is the number one factor for quality images while using AEC?
Patient positioning
When using AEC’s, and motion is a problem, what should you do?
Use high mA
Used to check x-ray timers in single phase machines only
Spin top tests
What is the formula for the single phase spin-top tests?
of dots = 120 x time
How are three-phase machine timers checked?
By physicist
What is the formula for the 3-phase spin-top tests?
360° x time = degree
