final exams review
What are some Adverse Effects of radiation?
hair loss and skin burns.
Other Signs in patients and personnel: skin cancers and other anomalies
What is the Radiation Units name and definition.
Radiation exposure - Easier to measure than radiation deposited and is measured in the following:
Roentgen or R = the production of 2.58 x 10 –4 Coulombs of electrical charge to one kilogram of air
What are two way you can measure radiation deposits in tissue?
Rad = radiation absorbed dose
Gray = absorption of one joule per kilogram of tissue
Name and the defined the two radiation protection standards?
A. Occupational Exposures (Annual)
The maximum amount of radiation that a radiation worker can normally be exposed to within a period of one year.
B. Public Exposures
The maximum amount of exposure that the general public can normally be exposed to within a period of one year
what is ALARA and what did it defined as ?
This means that all radiation exposures to patients and personnel are to be kept As Low As Reasonable Achievable without compromising image quality or diagnostic information.
How does practice standard radiation protection methods?
A. Practice: Time, Distance, and Shielding
B. Know your environment
1. Time: Minimize radiation exposure by limiting the time of radiation exposure. Practice the principle
of ALARA, As Low As Reasonably Achievable; the basic philosophy of radiation protection.
Example for student:
During fluoroscopy, when your physical presence is not required in the room, stand in the control area.
When you are present in the room, the 5-minute reset timer on the fluoroscopy unit will remind the
radiologist of elapsed time.
2. Distance: Maximize distance
Example for student:
During fluoroscopy, when your assistance is required in the room, you should stand as far from the
radiographic table as possible. During portable radiography, stand as far away as the exposure cord will
permit (6 feet).
3. Shielding: Maximize shielding
Example for student:
Stand in the control area during exposures. The glass observation windows are made of leaded glass,
and the walls are lead lined for additional protection.
Wear lead wrap-around aprons and thyroid shields during fluoroscopy and lead gloves if holding a
barium cup for the patient to drink.
Additional Notes:
• Close doors to hallways.
• Shield patients when indicated.
List types of protective barriers
Barriers are accomplished during the design of the room. Structural protective barriers are made of materials
having effective attenuating or absorption properties and of thickness sufficient to reduce exposure to desired
levels. Commonly used barriers include lead sheeting, concrete, lead glass, steel, and leaded acrylic.
Protective barriers are classified as either primary barriers or secondary barriers.
Primary Barriers: Those which can be struck by the primary beam exiting the x-ray tube.
Ex. The area of the floor around the periphery of the radiographic table and the wall on
which the upright film holder is mounted.
Secondary Barriers: Those which can only be struck by scattered and leakage radiation. Ex. Walls, control
booth etc.
Walls: All walls and doors up to 7’ are lined with 1/16” lead sheets. The glass observation
windows in the control area and between the classrooms are leaded glass (1/16” thick).
Doors: All doors have interlocks; when a door is open an exposure cannot be made or is
terminated.
Warnings: The doors to the hallways have warning sighs posted on the corridor. Above each door on the darkroom there are warning lights that are activated when the x-ray machines are on.
How must a radiographer understand and believe on his/her self according to the radiology field?
The radiographer must understand and believe himself/herself as a “responsible”, “competent” and “ethical health professional.
How did ethics, law and moral defined in radiology?
Ethics: is defined as philosophical analysis of the way people ought to behave toward one
another or what must be done in an orderly and organized society.
• Law: is a system of rules and regulations that govern people, relationships, behaviors and
interaction with the state, society and federal government.
• Morals: are ideas about right and wrong. Morals should not be confused with cultural habits
or customs such as wearing certain types of clothing. Instead, morals tend to be
deeply ingrained into a culture or religion and are often part of its identity.
• Moral beliefs: Killing is wrong, helping the poor is right, stealing is wrong, easing pain is
right.
What are some of the ethical issues?
High quality patient care
• Individual autonomy
• Technical advances
• Established standard of care
• Privacy & confidentiality
What is the " patient needs" in radiology?
• “Do unto others as you would have them do unto you.”
• The Platinum rule: (Autonomous)
• “Do unto others as they would have you do unto them.”
Standard of Care defined as
The legal standard is defined as the degree of care and skill utilized by a reasonable professional
practicing in the same or similar circumstances.
Work Related Stress:
Work related stress comes in a variety of forms including physical and/or psychological.
• Work related stress may be revealed in the body’s nonspecific response to any demand.
What are some of the Work Related Problems:
Time consuming procedure in fast pace environment
• ER, surgery, patient’s condition
• Job security
• Work overload
• Malcontent by limited variety of task
• Lack of control over own work
• Lack of support from supervisors, fellow workers
• And lack of understanding and support from home
What are some of the Work Related Stress in Performance Expectations according to Appelbaum:
Lack of consistency between the job description and subsequent performance review
• Reward systems
• Coping with active illness, burnout
• Cultural shock
• Turbulence associated with realities of health care for sick and injured people
Control:
Work related stress can be applied or created. Given enough time, stress often festers into
conflicts. The end result of conflict is in fact more stress. The radiographer must take control
over his/her work environment.
• The radiographer must exercise RESPECT, and comply with requirements not only for
demonstrating the same moral behavior practiced by other health care professionals but also for
applying medical radiation safely.
The Greatest Good:
A concept which is based on the idea of the best outcome for the greatest number of people
possible.
What are some properties and characteristic of an x-rays?
Electrically neutral (no mass, no charge)
• Travel in straight lines
• Travel at the speed of light, 186,000 miles/sec in a vacuum
• Affect photographic film emulsion
• Have a wide range of wavelengths and energy levels
• Can convert to heat when passing through matter
• Cause fluorescence of certain chemicals (IS)
• Can ionize gases
• Can produce biological changes in human tissue (cell damage)
• Produce secondary and scattered radiation
What are the four basic exposure factors of an x-ray and how do they define?
1. Milliamperage (mA): measures the current applied to the tube for thermionic or electron emission.
The mA determines the size of space charge). The mA is what constitutes the amount or quantity of
x-rays produced.
2. Kilovoltage (kV): measures the force that moves the electrons across the tube. The kV constitutes
the quality of the beam in terms of its penetrating ability. Generally, the higher the kV the more
penetrating the beam of radiation becomes.
3. Time: factor of duration is expressed in second (s) and is proportionate with mA. This means that if
you double the time, you will effectively double the quantity of x-rays produced. Consequently,
doubling the time tend to yield the same result as doubling the mA. The combination of mA and
time is called: milliampere seconds (mAs)
What are there two things that made up of radiographic quality?
Visual element and geometric element
What are the two virtual elements of a radiographic quality and how do they Define?
1. Density (Product of mAs): Represents the amount of overall blackness seen in the radiograph.
2. Contrast (Product of kVp): Illustrates gray tones or range of densities from lighter tones to darker tones.
What are some of the geometric element of a radiographic quality and how do they Define?
1. (FSS) Focal spot size: A smaller size focal spot reduces image blur.
2. (SID) Source to image distance: Optimal SID is 40”.
**Note: Greater SID yields better detail.
3. (OID) Object to film distance: Body part must always be placed as close to the film surface as possible. This reduces magnification and geometric blur.
4. DISTORTION: May be seen as inaccuracy in the size or in the shape of the object being radiographed.
a. Size distortion refers to magnification of the anatomy as seen in the radiograph. Controlling factors are SID and OID.
b. Shape distortion refers to misrepresentation (elongation or foreshortening) of the shape of anatomical structures as compared to actual object shape.
5. MOTION: is seen as image blurriness. Movement of the body part causes this during the radiographic exposure. This can be minimized by fast exposure time and restraint
Body positions
Erect: Standing in the upright position
Prone: Lying on the stomach; face down
Supine: Lying on the back; face up
Fowler: Lying down with the head positioned higher than the feet
Lithotomy: Lying supine with legs on stirrups
Knee-chest: Lying prone with knees and hips flexed forward
Trendelenberg: Lying down with the feet elevated higher than the head
Sims: Lying on the left side with the right knee flexed and brought forward
MSP (Median Sagital Plane): A plane that divides the body into equal left and right halves.
MCP (Median Coronal Plane): A plane that divides the body into equal front and back halves
Transverse plane: A plane that divides the body into top or upper and bottom or lower portions