What does deviation mean in radiography?
The deviation index quantifies the difference between the actual EI and the Target EI, and this feedback allows the radiographer to track and adjust his or her exposures.
What are the three important variables of x-ray tubes?
In order to evaluate the problem of x-ray tube heating, it is necessary to understand the relationship of three physical quantities: (1) heat, (2) temperature, and (3) heat capacity. Heat is a form of energy and can be expressed in any energy units.
What does ROI mean on x-ray?
In region-of-interest (ROI) imaging, a filter with a central aperture is used to substantially reduce patient dose outside of an ROI while maintaining or improving image quality within the ROI. The benefits of ROI imaging can be realized by using standard imaging equipment.
What are the three variables that are set on the x-ray machine to produce a diagnostic quality radiograph based on the patient’s size?
The three main components of any x-ray exposure are kVp, mA, and time. When a technologist prepares to make an exposure, kVp, mA and time must be set on the control panel.
How is SDI calculated?
SDI is calculated by the following formula: SDI = (your result – interlaboratory mean)/ interlaboratory SD. This index represents the number of standard deviations each result is from the mean.
How does the higher voltage affect the X-ray?
The increase in x-ray tube voltage increases the amount of radiation coming out of the x-ray tube, as well as the average photon energy (i.e., increased penetration). Accordingly, the tube current exposure time product value (mAs) is reduced to 36 mAs; whereas at 60 kV, the value was much higher (141 mAs).
Why is tungsten used in X-ray?
Tungsten has a high melting point and generates X-rays when irradiated with a high-speed electron beam. Because of these properties, it is used as an X-ray source for various X-ray tubes used in medical and security devices.
What is histogram analysis radiology?
Histogram Analysis. Histogram analysis is an image processing technique commonly used to identify the edges of the image and assess the raw data prior to image display. In this method, the computer first creates a histogram of the image (Figure 7-1).
Is ROI an algorithm?
The algorithm for Line ROIs is similar to that described above. However, Line ROIs do not enclose any area, and so in the description above substitute “length” for “area”. All shape intersections are performed using the standard Java intersect methods in the java.