Radiation Protection - Chapter 12
What are two examples of involuntary motion?
-Parkinson's disease -mental disorder
Two concerns relate to patient dose in CT scanning, what are they?
-skin dose -dose distribution
Name (6) unnecessary radiologic procedures;
1. CXR on admission to hospital 2. CXR as part of pre-employment 3. CXR as part of routine check-up 4. CXR for TB screening 5. L-Spine as part of pre-employment 6. Whole body CT screenings
Give (6) technical exposure factors considerations besides "mass per unit volume of tissue":
1. Effective atomic numbers and electron densities 2.Image receptor 3. SID 4. Filtration 5. Type of generator 6. Balance between densities and contrast
The amount of radiation (during xrays) received by a patient may be specified in (3) ways. What are they?
1. Entrance Skin Exposure (ESE) 2. Bone marrow Dose 3. Gonadal dose
As many as _____ multiple slices can be acquired simultaneously during a CT exam.
128
CT of the body, gives off a patient dose of ____ to ____ mGy.
20 / 40
The Alliance consists of more than ____ medical societies.
24
CT of the head, patient dose ranges from ____ to ____ mGy.
30 / 50
The use of an air gap technique requires the selection of technical exposure factors that are comparable to those used with an ______ ratio grid.
8:1
Air gap techniques are not as effective when kVp settings are _____ or above.
90
Alternative procedure to the use of radiographic grid for reducing scattered radiation;
Air gap technique
Studies indicate that patient ____ increases with the use of ____ when a repeat exposure is needed.
ESE / FGP
The practice of using fluoroscopy to determine the exact location of the central ray before taking a radiographic exposure:
Fluoroscopy Guided Positioning (FGP)
Motion caused by muscle groups such as those associated with the digestive organs of the heart and cannot be willfully controlled:
Involuntary motion
Why is entrance skin exposure (ESE) the most frequently used method for determining radiation received by patients?
It is the simplest to determine
What is the purpose of the repeat analysis program?
It's in place to protect the patient.
What date did the Alliance kick off the Image Gently Campaign?
January 22, 2008
__________ became the first state in the U.S. to endorse the Image Wisely & Image Gently Campaign on ______________.
Minnesota / December 2012
How can the xray technologist compensate for involuntary motion by the patient?
Shortening the length of exposure time adequately.
What is the Image Gently Campaign?
The campaign includes dissemination of information on pediatric CT dose reduction.
What is the Image Wisely Campaign?
The campaigns objective is to lower the amount of radiation used in xray exams and eliminate unnecessary xray exams.
What does the word "pitch" mean in regards to CT imaging?
The relationship between the movement or advance of the patient table and the beam collimator dimension.
The sensing devices most often used to measure skin dose directly:
Thermoluminescent dosimeters (TLD)
Give a brief description of how the air gap works:
This technique removes scatter radiation by using an increased OID receptor distance. Low energy X-rays get absorbed by the air.
Genetically Significant Dose (GSD) takes into consideration that some people receive radiation to their repro. organs during a given year. T or F?
True
CT was previously referred to as computed ______ tomography.
axial
Skin dose represents the absorbed dose to the ____________.
epidermis
The entrance exposure from a CT also may be compared with the entrance exposure received during a ____________.
routine fluoro exam
Motion controlled by will is classified as _________ motion.
voluntary
What are the two types of patient motion?
voluntary & involuntary