what is the sharpness of structures or detail in the radiographic image?
recorded detail
what is the misrepresentation of size or shape of the object that is being radiographed?
distortion
How does mAs affect optical density?
controlling factor: as mAs increases, density increases
how does kVp affect optical density?
as kVp increase the electrons within the tube having more energy creating a darker image/
How does SID affect optical density?
as SID increases Density decreases
How does part thickness affect optical density?
as part thickness increases attenuation of the beam increases and density decreases
How does tissue density affect optical density?
as tissue density increases ( how tightly packed together the atoms of the tissue are) attenuation increases and this density decreases
How does developer temperature and replenishment rate affect optical density?
as each of those increase the density increases
How does field size affect optical density?
as field size decrease less photons are in the beam and therefore density decreases
how does grid ration affect density?
any time a grid is use mAs will need to be increased to compensate otherwise a loss of density will occur as grid ratio increases mAs needed to compensate increases
how does film/screen speed affect density?
as speed increases more ionization of silver halide crystal and more light produced by the screen creates the density to increase
how does oid affect density
as oid increases an air gap is created causing scatter to miss the film reducing density
how does fog affect density?
fog of any kind always increase density and reduce radiographic quality
how does pathology affect density?
pathology can be classified as either additive or destructive
additive condition cause an increase in thickness and effective atomic number or tissued density which would decrease density
destructive condition causes a decrease in thickness effective atomic number or tissue density as a destructive condition worsen density increases
how does voltage waveform affect density
high frequencey and 3 phase xray generators emit more xray photons in a given time period than single phase generators. high frequency and 3 phase units required 50% less mAs that what a single phase requires. =darker image with 3 phase using less mAs
How does filtration affect density
filtration remove the low energy xray photons from the beam this decreases bean intensity and this density
What is base plus fog?
the density of the film at no exposuse
What does window level adjust?
brightness (density)
What does the toe region represent?
the lighter densities
what does the shoulder portion represent?
the darker densities
What is Dmax?
the highest point on the curve and represents the darkest density the film is capable of recording; any exposure beyond dmax results in solarization or the film actually becoming lighter
what is the portion of the curve between the toe and the shoulder?
straight line portion
what is defined as the slope of the straight line portion
contrast
what is exposure latitude
is the range of exposures that produce densities within the diagnostic range. As latitude increases contrast decreases.
wide- toe shoulder far apart= low contrast
narrow- toe shoulder close together= high contrast
What does widow width control?
contrast of the image
What does focal spot size do to resolution?
as focal spot size decreases, resolution increases
what does SID do to resolution
As SID increases resolution decreases
what does OID do to resolution
as OID decreases resolution increases
How does film screen speed affect resolution?
as film screen speed increases resolution decreases
What does matrix size do to resolution?
A matrix is a square series of pixels that form and image as matrix size increases resolution increases
How does SID and OID affect distortion
As SID decreases magnification increases
As OID increases, magnification increases
What is the purpose of a QM team?
The purpose of a quality management program is to control or minimize these variables as much as possible.
What is expected quality?
Expected quality is that level of quality that is expected by the customer and may be influenced by outside factors such as word of mouth.
What is perceived quality?
•Perceived quality is the customer’s perception of the product or service. It is highly subjective.
What is actual quality?
•Actual quality is the level of quality that uses statistical data to measure outcomes and considers all factors that can influence the final outcome
What is the cost of quality Management team; What is the return on investment be considered?
•The cost of such a program is personnel time and test equipment.
•The return on investment includes lower repeat rates, less equipment downtime, savings in film and chemicals, greater department efficiency, and increased customer satisfaction.
What is scientific management?
Job tasks were broken down into simpler but separate steps that were repeated over and over again as in an assembly line. Only specific people were assigned the task of inspection
T/F: a quality assurance is optional
true?
What is the Care Bill?
•In 2000, the Consumer Assurance of Radiologic Excellence Act (CARE) was introduced in Congress. This act mandated educational and training requirements for all technologists. The CARE bill has yet to be passed. It has been renamed the Consistency, Accuracy, Responsibility and Excellence in Medical Imaging and Radiation Therapy Bill to include the disciplines governed in the bill that are not directly related to radiology. In addition to improving the quality of care, the CARE act would save money by a reduction in repeat rate associated with a properly trained technologist.
What is Hipaa?
In 1996 the Health Insurance Portability and Accountability Act (HIPAA) mandated policies to protect patient security and confidentiality. The final rules went into effect April of 2005. National standards were established including electronic patient record system security requirements, standard electronic formats for insurance transactions, and standard identifiers and codes for institutions, personnel, diagnoses and treatments.
What is SMDA?
The Safe Medical Devices Act (SMDA) of 1990 mandates that medical facilities must report to the FDA and manufacturer any incidence of death or serious injury caused by a medical device.
what is MQSA
In 1992 the Mammography Quality Standards Act (MQSA) mandated quality standards for8all persons and equipment involved with mammography.
is TJC accreditation mandatory or voluntary?
voluntary
What is quality control?
Quality control is that part of QA that deals with the monitoring and maintenance of the equipment used in creating the image
What is quality assurance?
Quality assurance assures excellence in healthcare through the systematic collection and evaluation of data.
What is quality improvements?
Continuous quality improvement (CQI), also known as total quality management (TQM), total quality control (TQC), total quality leadership (TQL), total quality improvement (TQI), or statistical quality control (SQC), does not replace the concept of QA/QC but takes it to a higher level.
Instead of ensuring and maintaining quality, CQI continually improves quality by focusing on improving the system or process. The organization is viewed as a whole instead of by department. Quality should be built in at every level. Each person involved in the process should actively participate in quality improvement.
What is the 85/15 rule? what is the 80/20 rule?
The 85/15 Rule states that the process or system is the cause of the problems 85% of the time and people within the process are the cause 15% of the time.
The 80/20 Rule states that 80% of the problems are the result of 20% of the causes.
What is a key quality characteristic?
KQCs are those qualities that have been identified as being most important to the customer.
These qualities must be constantly measured and improved in order for customer satisfaction to increase.
What is brain storming?
Brainstorming is a group process used to develop a large collection of ideas without regard to merit or validity.
what is a focus group?
•A focus group is a small group that focuses on a particular problem and derives a solution.
what is a quality improvement team?
•A quality improvement team is a group that implements the solution derived by the focus group.
what is a quality circle?
•A quality circle is a group composed of supervisors and workers from the same department or who have a similar function in a different department. The circle functions to identify problems with processes and then formulate solutions. Quality circles should be scheduled to meet regularly.
what is multi-voting?
•Multi-voting is a method of eliminating ideas formulated during a brainstorming session. All members of the brainstorming session are given a list of the ideas formulated and then asked to vote on which they consider the most important. The ideas with the fewest votes are eliminated and the process is repeated until one key idea remains.
what is consensus?
•Consensus may also be used after a brainstorming session. Group members come to an agreement through discussion on the most important idea.
what is work teams?
•Work teams focus on solving a complete problem rather than focusing on a particular step in a process. These teams may be empowered by management to take corrective action to solve the problem.
what is problem solving teams?
•Problem solving teams work on specific tasks and meet to solve specific problems. They function to identify, analyze, and solve quality and productivity issues.
What are the steps in the TJC 10 step process?
1) assign responsibilities for the department
2)Delineate the scope of care and service provided by the dept
3)identify important aspects of care
4) identify indicators and performance measures
5) establish a mean to trigger evaluation
6) collect and organize data
7) initiate evaluation
8) take action and improve care and service
9) assess effectiveness of action and maintain improvement
10) communicate results of affected individuals and groups
What is SWOT analysis?
•SWOT analysis looks at the internal and external environment. The internal environmental factors include strengths and weaknesses of an organization. The external factors are classified as opportunities or threats.
what is six sigma?
•Six Sigma is a management strategy that seeks to identify and remove causes of errors in processesSix sigma allows you to measure how many errors exist in a process so that they can systematically be eliminated.
evaluation of equipment performance to ensure quality and safety.
Equipment quality control
the establishment of processes to accomplish required departmental tasks. This involves data collection and analysis for continuous process improvement, cost control, personnel management, personnel education, equipment acquisition, and communication with vendors and other departments within the organization.
administrative responsibilities –
what is the ability to identify potential risks to employees, patients, and visitors and the establishment of processes that minimize these risks
Risk management
what ensures ALARA principles are adhered to
Radiation safety program
what is the entire set or group of items measured.
•A population
what is the number of items actually measured from a population. Choosing a portion of the population makes data collection more timely and efficient.
•A sample
what is the information or measurements acquired from the sample.
•A data set
is the number of times a particular value of a variable occurs or the number of observations of an event.
•Frequency
what are those variables that change in response to independent variables
•Dependent variables .
•Independent variables
are those variables that are purposely manipulated to cause a change in the dependent variables.
what are those variables that have an infinite range of possible values
•Continuous variables .
What are those variables that have only two possibilities.
•Dichotomous variables
what is central tendency?
is the central position of a sample frequency. Measures of central tendency include the mean, median, and mode. The mean is the average. The median is the data point exactly in the middle. The mode is the most commonly occurring value.
what is the consistency or reproducibility of the results and is also known as precision. Reliability can be affected by sample size and the data collection process itself.
Reliabilty
what is the ability to measure what we are actually tying to measure. In other words, how well does the value we measured represent the actual property we want to study? This is also known as validity
Accuracy
what is the systematic difference between the true value of a property and measurements of that property. It is the presence of systematic error.
bias
What is the difference between the measured value and the true value of a variable. Errors may be either systematic or random. Systematic or determinate errors result from malfunctioning equipment, not correcting for outside influences, or poor data collection processes. Random or indeterminate errors result from statistical fluctuations.
error
What is the difference between the highest and lowest values measured.
range
is a pictorial representation of the steps in a process.
A flow chart
is used to demonstrate the causes and effects of different variables on a quality or characteristic.
•A cause and effect diagram (fishbone chart or Ishikawa diagram)
•A histogram is
a bar graph in which the most frequent occurrence of a quantity is plotted in the center.
what is a variation of the histogram in which the most frequent occurrences are to the left and decrease as you move to the right.
•A Pareto chart
what is a traditional graph with data points plotted throughout. It is designed to determine whether a relationship exists between two variables in a process. Once the points have been plotted, the graph is examined to determine if there is a pattern.
scatter chart
what is a modified tend chart in which upper and lower limits are placed withacentrallinethatindicatesthenorm. If the plotted data point falls above or below the limits, the process is unstable.
Control chart
what indicates whether key indicators are moving up or down over time
trend chart (run chart)
What is ALARA?
The ALARA principles of time, distance, and shielding are effective means of reducing exposure Each radiographer has the responsibility to adhere to ALARA principles (high kVp/low mAs, high speed image receptors, filtration, collimation, optimal processing conditions, repeats, projection, shielding).
What is digital dose creep?
What are the NRC occupational exposure regulations?
Radiation workers are allowed a maximum occupational exposure of 5 rem per year according to the NCRP. All personnel must wear a radiation monitoring device. Pregnant workers should be issued a second monitoring device to be worn at the waist to monitor fetal exposure. Fetal exposure should not exceed .05 rem per month or .5 rem for the entire gestational period.
What does the dosage have to be to post a radiation caution sign?
Warning signs marked “Caution: Radiation Area” should be posted for areas where dosage may exceed 5mr/hr.
What must the thickness of lead aprons be?
Lead aprons must have a minimum lead equivalent thickness of .5 mm and cover 75-80% of the active bone marrow of the person wearing it.
What is the term used to describe the increased sensitivity of exposed film?
Latensifcation
T/F A darkroom is considered a scientific lab by OSHA
T
What creates sparks of white light and puts artifact on films?
static electricity
What conditions cause static electricity?
-countertops/floor mats not grounded
-film being slid into a cassette not placed
-clothing made of synthetic instead of natural
T/F Darkrooms do not need to be well ventilated.
F, they do
What color should darkrooms be painted and why?
pastel colors, to increase the reflection of the light emitted by the safelight.
What is defined as the capacity ot handle 2.5 times the max outflow of the processor when all drains are open?
adequate drainage
How many feet should safelights be from countertops and feed trays?
3-4 feet
Describe orthochromatic film.
mainly sensitive to green portion of the spectrum but is also sensitive to blue-violet portion. NOT SENSITIVE TO RED
Describe panchromatic film.
sensitive to all colors of light, DOES NOT ALLOW FOR ANY safelight conditions
When performing leakage testing and safelight testing, in which order should they be done?
leakage testing should always be done before safelight tests.
Describe the procedure for leakage testing.
turn on all lights surrounding the darkroom, enter darkroom and turn off all lights including safelights. allow eyes to adjust and check for any leakage. Turn on the overhead lights and inspect the countertops, and feed trays for cleanliness. Check chemical tanks for good ventilation, Check film storage.
T/F Safelight fog can be attributed to cracked or worn filters due to using the wrong bulb wattage.
T
What is the acceptance limits for safelight testing?
should not exceed .05OD for double emulsion and should not exceed .02 OD for single.
What temperature should film be stored at?
55 to 75 F
What humidity should film be kept at?
30 to 60 percent
IF film is froze how long can the shelf life extend after its expired?
however long it was kept in the freezer
What is good chemical storage temp?
40 -80 F
Why should chemicals be stored in minimal lighting?
because the developer solution can degrade if exposed to bright light
what is luminance?
brightness
How do we measure viewbox luminance?
with a photometer
T/F Film duplicators should be able to copy optical densities of up to 2.5 OD form the original.
T
When duplicating film the original copy should be with what OD for each step?
.02 OD
What is the capability of a screen to produce visible light?
screen speed
T/F The thicker the phosphor layer, screen speed will decrease.
F, screen speed will increase
T/F as phosphor size increases, screen speed increases.
T
T/F As phosphor size increases, resolution increases.
F resolution decreases
T/F As the thickness of the phosphor layer increases, resolution decreases.
T
T/F Reflective layer may be added to the screen to increase speed.
T
What is the measurement of an image obtained form a single point?
Point spread function
What requires the use of an aperture with a slit 10micrometers wide cut in the center.
line spread function
What is a test that uses a wire mesh test tool and is placed on top of a cassette and exposed, then evaluated?
Film/screen contact
T/F Intensifying screens must be free of dirt and stains for good image quality
T, should be cleaned with antistatic every 6 months
What is the invisible image?
latent
What is the another name for the visible image?
manifest
What are the reducing agents for the developer?
Phenidone and Hydroquinone
Describe Phenidone
works quickly and only in light areas of exposure.
-fine detail
-subtle shades of gray
Describe Hydroquinone
works slowly in heavily exposed areas.
-dark densities
-responsible for Dmax
When phenidone and hydroquinone are combined they work faster together, this is termed what?
superadditivity or synergism
How does oxidized developer appear?
dark and muddy, may have an odor of ammonia
T/F when perservative is exposed to air it increases oxidation to the reducing agents.
F it decreases oxidation
What is the hardener for the developer?
Glutaraldehyde
How is the Developer activity measured?
temp., time, concentraiton, and pH
Excessive pH does what to OD and oxidation?
increases
A decrease in temp. does what to OD?
decrease
The longer the immulsion time does what to OD?
increses
When talking about contamination, what is this a major problem for?
The developer, (can't have fixer) as little as .1% will destroy
What is replenishment?
fresh developer solution is added and mixed in properly
WHat is the purpose of the fixer?
to remove the unexposed silver halides from the film.
What is the clearing agent aka?
hypo
What are some hardeners for the fixer?
aluminum chloride, potassium alum, and chrome alum
What is when the emulsion must be hardened to keep the image form fading or being scratched to be permanently stored?
tanning
Why is washing with water done?
to remove developer and fixer solutions from the film
What is the main problem in archiving films?
fixer retention
Where would you correct a fixer retention problem?
wash tank should be checked for proper level and flow rate
Explain a fixer retention test.
Test kits should be available, drop test soultion is placed on a processed film and allow to set for 2 min. Check chart for discoloration
T/F Processing solutions are health hazards.
T
What are PPE standards?
personal protective standards to ensure that employees have proper protection from workplace hazards. developed by OSHA
In the processor, what is the most likely to break down?
the transport system, because it is the most complex
What is the difference between volume replenishment and flood replenishment?
volume=used for high volume units, replenishment is activated when a film is first placed on the feed tray and continures until film is all the way into processor
flood=used for low volume situations, replenishment is controlled by a timer that automatically floods the processor with addtional solutions ar regular intervals
How does the developer temp affect density?
if temp is below optimal=decrease density
-if temp is above optimal=increase density
What is the acceptance limits for developer temp?
should not vary by more than +-.5 degrees F from manufacturer recommendations
What are the fixer temp acceptance limits?
should remain within +- 5 degrees F of the developer to avoid reticulation marks
What are reticulation marks?
fine grooves
What controls developer time?
transport system
If the developer time decreases what happens to density?
it will also decrease
If developer time increases what will happen to density
increase
What is under-replenshment?
slowing, will produce light films
What is over replenishment?
overacting agent, too dark will produce fog
T/F under replenshment will increase density.
F over will over replenshment will increase
What should the pH of the developer solution be between?
10 ot 11.5
What should the pH of the fixer be between?
4 to 4.5
What is used to evaluate solution concentration, and measures specific gravity?
hydrometer
What is the density of the solution divided by the density of the equal amount of water?
specific gravity
What is the most cause for breakdown of processor?
dirty processor
What should be done for daily cleaning of the processor?
-shutdown, remove crossover racks of the processor and rinse with water
-lid should be raised, to avoid condensation
What should be done monthly for processor cleaning?
-all tanks rinsed with water and refilled with proper solutions
-developer should be seasoned
-add starter solution to developer
What should daily maintenance for the processor include?
rinsing racks, leaving the lid open at shutdown, and running four unexposed 14x17 films through at start of ea. day.
What are some tools for sensitometry?
sensitometer, densitometer, box of control film, and a control chart
What is an instrument used to expose a film to a uniform optical step wedge pattern?
sensitometer
What is bromide drag?
bromide ions being released and coating the trailing areas of the film, occurs when film is fed into processor more exposed end first
What are the acceptance limits for Base plus fog?
should not vary more than +-.05 for double emulsion and +-.03 for single from the operating level
What is the acceptance limits for speed indicator?
should not vary by more than +-15 form the operating level
what is the acceptance limits for contrast indicator?
should be within +- .15 of operating levels
If base plus fog is outside the acceptance limits what will happen and why?
fog, caused by increase in developer temp, increase in developer time increase in replenishment rate, or fogged film
What causes speed indicator to be outside acceptance limits?
increased developer temp, increased developer time, increased replenishment rate or excessive concentration
What causes contrast indicator to be outside acceptance limits?
increase in developer time, temperature, replenishment rate, or over concentration
T/F Fog increases contrast, decreases density
F increases density, decrease contrast
What is considered 5 or more points moving in the same direction for general radiography and 3 points for mammography?
trend
What is the process done when a control box of film is almost empty, 5 films form old box and 5 from new are exposed with sensitometer and processed, the average base plus for, MD, and DD for ea. group are calculated. the operating level is then adjusted by the difference between these averages?
crossover process
What is a measure of contrast?
average gradient
What measures whether or not the processor is consistent?
Sensitometry
What indicates whether or not it is optimal?
average gradient
T/F Daylight systems do not have to do sensitometry.
F, they do but you just put the film in a cassette after it has been exposed and run it through your daylight system
