Radiography Flashcards
The target/anode is angled about 15 degrees exhibits the ___ principle
Line focus principle
Leakage Kair should be
<1mGy/hour a 1 m
The sum of leakage and scattered radiation resulting in exposure to any personnel in teh x-ray room (radtech, radiologists)
Secondary radiation
Heat energy depostited in the focal spot is known as?
tube loading
Virtually _% electrical energy supplied to x-ray tubes is converted to heat
99%
occurs because x-rays traveling in the anode direction are attenuated more than those traveling in the cathod direction
Heel effect
Lowest x-ray tube voltage in radiography
50 and 65kV
Distance from the x0ray tube source to the image receptor
Source to image distance (SID)
Distance from the x-ray tube source to the front (surface) of teh patient
Source to skin distance (SSD)
Most common source to image distance (SID)
100 cm
Grid ratio for thicker body parts
Higher grid ratios
X-ray exposure termination device
Automatic exposure control
provides a universally understood quantitative measure of Kair at any image detector
Exposure index (EI)
Detercote image value indicating an exposure that is double (or half) the target K at the image receptor
+3 (or -3)
Source to image distance (SID) of chest x-ray
180 cm
beside radiography is generally __cm
100 cm
SID in abdominal and pelvic radiography
100 cm
use of large focal spot (maximum power) reduces the exposure times below __ms
100ms
Grid ratio used to reduce the amount of scattered radiation
10:1
SID in extremity radiography
100 cm
Grid ratio used to reduce the amount of scattered radiation
10:1
Skin dose in radiography
<10mGy
Embryo dose associated with an abdominal examnination
1mGy
Patient effective dosese in radiography
<0.1 mSv to 1mSv
