Table of Contents
- 1 What is the commonly used method for automatic exposure control in an X-ray machine?
- 2 What is an automatic exposure control system?
- 3 What does an automatic exposure control AEC device utilize?
- 4 How much radiation do you get from fluoroscopy?
- 5 What are the two types of incoming line current?
- 6 What factors must be taken into consideration by the radiographer when using an automatic exposure control AEC technique system?
- 7 Is fluoroscopy safe?
- 8 Is fluoroscopy more radiation than CT?
- 9 How does an automatic exposure control system work?
- 10 What is AEC in radiology?
- 11 How does an AEC device work?
What is the commonly used method for automatic exposure control in an X-ray machine?
TABLE 1
| Patient Width, cm | Modulation Strength (b) | |
|---|---|---|
| 0.30 | 1.00 | |
| 28 | 110\% | 38\% |
| 36 | 100\% | 100\% |
| 44 | 91\% | 265\% |
What is an automatic exposure control system?
Automatic exposure control (AEC) systems are designed to adjust the kilovoltage, milliamperage, or exposure time in order to obtain an image of diagnostic quality, be it for radiography or fluoroscopy.
What is APR in radiology?
Anatomically programmed radiography (APR) is a system of preprogrammed exposure technique set- tings that is organized by position and examination and set through the control panel of the radiography unit. Essentially, an APR system is an electronic technique chart.
What does an automatic exposure control AEC device utilize?
In projectional radiography an AEC system uses one or more physically thin radiation ionization chambers (the “AEC detector”) which is positioned between the X-ray source and the x-ray receptor.
How much radiation do you get from fluoroscopy?
Getting a fluoroscopic procedure exposes a patient to as much radiation as 250 to 3,500 chest X-rays. For perspective, a person gets the equivalent of one chest X-ray from normal background radiation in about two and a half days.
Where is the automatic exposure control AEC chamber located?
In radiography, the automatic exposure control device is placed in front of the image receptor. In mammography, the automatic exposure control device is placed underneath the image receptor.
What are the two types of incoming line current?
24 Cards in this Set
| Name 3 types of diagnostic radiographic tube-support systems. | Overhead, floor-to-ceiling, floor, mobile, and C-arm |
|---|---|
| Whatare the 2 types of incoming line current? | Single phase and three phase |
| How many pulses are there per Hz for 1 phase and 3 phase power? | single = 2 pulses three = 3 pulses |
What factors must be taken into consideration by the radiographer when using an automatic exposure control AEC technique system?
There are certain decisions that must be made by the radiographer, such as proper sensor selection, appropriate kVp and mA selection, density control adjustment, and correct patient positioning both anatomically and relative to the proper sensor.
What is AED in radiology?
Automatic Exposure Detection (AED) sets the appropriate exposure settings for youto produce the best possible images. You don’t have to tinker around with the settings and take multiple X-ray images to improve on image quality because the equipment does it for you.
Is fluoroscopy safe?
Fluoroscopy is a safe procedure. However, there are some risks that you should talk about with your doctor: Being exposed to radiation like x-rays can increase your chance of cancer.
Is fluoroscopy more radiation than CT?
The mean effective radiation dose for patients is lower for fluoroscopy-guided compared with CT-guided lumbar spinal injections. The mean radiation exposure for interventionalists is higher during fluoroscopy-guided compared with CT-guided lumbar transforaminal epidural and lumbar facet joint injections.
How does an ion chamber work?
The operating principle of an ionization chamber is simple: ionizing radiation from the source (X- or gamma rays, electrons) creates an ionization of the gas atoms. A voltage is applied between the electrodes. Negative charges are attracted by the anode, positive charges by the cathode.
How does an automatic exposure control system work?
All automatic exposure control devices work on the same physical principle,based upon the ability of radiation detection devices to convert radiant energy into an electrical current. An AEC system uses a physically thin radiation ionization detector “AEC detector”.
What is AEC in radiology?
Automatic exposure control (AEC) is a device incorporated into radiographic and mammographic imaging systems. Its function is to automatically terminate exposure when a preset amount of radiation has been detected.
What determines the amount of radiation exposure to the image receptor?
Once a predetermined amount of radiation is transmitted through a patient, the x-ray exposure is terminated. This determines the exposure time and therefore the total amount of radiation exposure to the image receptor.
How does an AEC device work?
A weak ionization signal from the AEC detector is integrated as a ramp shaped voltage waveform. This ramp signal rises until it matches a pre-set threshold. At this point the x-ray exposure is terminated. AEC devices are calibrated to ensure that similar exams have linearity in exam densities.