Meaghan Piretti Study Guide
• What side of the x-ray tube positive
Anode
• What side of the x-ray tube is negative
Cathode
• What is the role of the glass envelope
Containment and maintains the vacuum
• What is the role of the tube housing
Prevents leakage and insulates
• What end of the tube has the filament and focusing cup
Cathode
• What are the types of anodes
Rotating and Stationary
• What is the anode made of
Tungsten
• Why is Tungsten the chosen material for the anode
Has a high atomic number meaning it has a high melting point
• Describe the induction motor
Stator on the outside and Rotor on the inside
• What is a stator
Electric motor that turns the rotor at high speed
Rotating magnetic field when energized
• What does the rotor do
Spins the anode allowing heat to be spread out across a larger area
• What do the bearings of the induction motor do
Support and enables rotation
• Define Anode heel effect
Variation in x-ray intensity between anode and cathode sides of the tube
, • What side of the x-ray tube has the more intense beam
Cathode
• Why is the beam more intense on the cathode end
X-rays produced deeper within the anode must pass through more material
which absorbs some of the beam, the absorption reduces intensity on the
anode side
• If the degree of anode angle decreases what will happen to the anode heel
effect
It increases, a smaller angle means x-rays have to travel through more
anode material to exit
• Define the line focus principle
Large Actual focal spot that spreads heat while maintaining a small effective
focal spot for better image detail
• What is larger, the actual focal spot or effective
Actual
• Where is the actual focal spot located
On the surface of the anode target
• Which focal spot goes towards the pt, actual or effective
Effective
• If you decrease anode angle (choose small focal spot) how will that affect
the effective focal spot size
It also decreases
• Define off focus radiation
Radiation produced outside the actual focal spot which causes blurred
edges or ghost images
• Define tube loading
The amount of heat energy generated in the x-ray tube during an exposure,
heat units
• What is the formula for heat units
HU= kVp x mA x time (s) x wave form factor
• What side of the x-ray tube positive
Anode
• What side of the x-ray tube is negative
Cathode
• What is the role of the glass envelope
Containment and maintains the vacuum
• What is the role of the tube housing
Prevents leakage and insulates
• What end of the tube has the filament and focusing cup
Cathode
• What are the types of anodes
Rotating and Stationary
• What is the anode made of
Tungsten
• Why is Tungsten the chosen material for the anode
Has a high atomic number meaning it has a high melting point
• Describe the induction motor
Stator on the outside and Rotor on the inside
• What is a stator
Electric motor that turns the rotor at high speed
Rotating magnetic field when energized
• What does the rotor do
Spins the anode allowing heat to be spread out across a larger area
• What do the bearings of the induction motor do
Support and enables rotation
• Define Anode heel effect
Variation in x-ray intensity between anode and cathode sides of the tube
, • What side of the x-ray tube has the more intense beam
Cathode
• Why is the beam more intense on the cathode end
X-rays produced deeper within the anode must pass through more material
which absorbs some of the beam, the absorption reduces intensity on the
anode side
• If the degree of anode angle decreases what will happen to the anode heel
effect
It increases, a smaller angle means x-rays have to travel through more
anode material to exit
• Define the line focus principle
Large Actual focal spot that spreads heat while maintaining a small effective
focal spot for better image detail
• What is larger, the actual focal spot or effective
Actual
• Where is the actual focal spot located
On the surface of the anode target
• Which focal spot goes towards the pt, actual or effective
Effective
• If you decrease anode angle (choose small focal spot) how will that affect
the effective focal spot size
It also decreases
• Define off focus radiation
Radiation produced outside the actual focal spot which causes blurred
edges or ghost images
• Define tube loading
The amount of heat energy generated in the x-ray tube during an exposure,
heat units
• What is the formula for heat units
HU= kVp x mA x time (s) x wave form factor
