Patient Radiation Dose Management Flashcards
Exposure to medical radiation is up by ___ in the U.S.
18%
Patient dose is usually estimated by
conducting simulated x-ray exams with human phantoms and test objects.
Patient dose from diagnostic x-rays can be reported in three ways
Exposure, Bone Marrow Dose and Gonadal dose
Bone Marrow is important because
it can indicate radiation-induced leukemia Bone.
calculated from ESE
Marrow dose is estimated by
Entrance Skin Exposure.
Entrance skin exposure
Most common way to report dose, easy to measure directly
Gonadal dose
target for genetic effects, easy to measure or estimate
Entrance Skin dose most often referred to as _____
“patient dose”
Entrance Skin dose(ESD)
- Easily measured with or without measurement devices
- Entrance Skin Dose is used to estimate Bone Marrow Does
- Efficiency of the radiology equipment will change these doses from facility to facility.
Thermoluminescence Dosimetry
- Like the film badge can be worn up to 3 mos.
- Must be processed – can measure as low as 1 millirem.
- Highly sensitive , compact
- Most accurate and not affected by humidy.
- Twice the price of a film badge.
Thermoluminescence Dosimetry uses
lithium fluoride (LiF)
what monitor is most frequently used to measure pt. exposure?
Thermoluminescence Dosimetry
disadvantage of Thermoluminescence Dosimetry (TLD)
- Higher cost
- Can only be read once and then reused
- Previous records are erased – therefore no permanent or legal record of exposure
We can Reduce Unnecessary Patient Dose by unnecessary exams of what kind?
-mass screening of TB
-hospital admission
-preemployment physicals
-periodic health exams
-emergency room CT
-Whole body multislice spiral CT screening
-
Reducing Unnecessary Patient Dose
unnecessary exams, repeat exams, technique and positioning
Frequency of repeats may range as high as __
10%