The primary exposure technique factors the radiographer selects on the control panel are
milliamperage, time of exposure, and kilovoltage peak (kVp)
. Depending on the type of control panel, milliamperage and exposure time may be selected separately or combined as one factor, milliamperage/second (mAs).
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 are the important factors to be considered in determining the exposure time?
Other important factors to consider when defining exposure are the timeframe
(induction and latent periods)
, changes in exposure status or exposure to other therapies, and consistency and accuracy of exposure measurement.
What is the exposure indicator?
The exposure indicator (EI) is
a numerical
.
parameter used in computed radiography (CR) to inform operators about the amount of expo
– sure to the imaging plate.
What is exposure factor in radiography?
Prime Factors of Radiographic Exposure. Exposure is a broad term used to describe
the x-rays that the patient is exposed to, the amount of x-rays in the primary beam, and also the amount of x-rays that reach the image receptor (IR)
. The x-ray beam is often described in terms of its quantity and its quality.
What are the exposure factors?
Exposure factor (EF) is the
subjective, potential percentage of loss to a specific asset if a specific threat is realized
. The exposure factor is a subjective value that the person assessing risk must define. The exposure factor is represented in the impact of the risk over the asset, or percentage of asset lost.
What four factors affect the proper scale of radiographic contrast?
In conventional radiography, the contrast depends on the
size of the grains, the development time, the concentration and temperature of the developing solution, and overall film density
. As conventional film use has been reduced, we will not discuss the details of these factors.
What is the principal function of the automatic exposure control?
Its function is
to automatically terminate exposure when a preset amount of radiation has been detected
. Automatic exposure control systems help to provide a consistent optical density/signal-to-noise ratio between images, regardless of patient-centric factors such as size and density.
When do we use AEC?
A medical radiographic exposure is always initiated by a human operator but an AEC detector system
may be used to terminate the exposure when a predetermined amount of radiation has been received
. The intention of AEC is to provide consistent x-ray image exposure, whether to film, a digital detector or a CT scanner.
What is automatic exposure rate control?
Automatic exposure rate control
maintains the radiation dose per frame at a predetermined level
, adapting to the attenuation characteristics of the patient’s anatomy and maintaining a consistent level of image quality throughout the examination.
What are the different exposure indicators?
The exposure indicator has as many different names as there are vendors in the market. The names include
S-number, REG, IgM, ExI and Exposure Index
. Carestream’s computed radiography (CR) and digital radiography (DR) systems both reference their exposure indicator as the exposure index or EI.
What is exposure chart?
Introduction. X-ray exposure charts are
individual to the x-ray machine, intensifying screen, film and developing combination
. An exposure chart for one x-ray machine cannot be transferred to another machine even if it is identical. Exposure charts are important to: Provide consistent results.
Is exposure index the same as ISO?
ISO Sensitivity (or ISO speed) is a measure of how strongly an image sensor and/or camera responds to light. … Exposure Index (EI) is a camera setting derived from one or more of the Sensitivity measurements. It is used to determine the camera’s exposure in response to a light level measurement.
How do you calculate factor exposure?
Once a factor has been defined, the factor exposure of an index can be measured as
the sum of the factor scores of the index’s constituents, multiplied by each constituent’s weight in the index
.
What is air gap technique?
Air gap technique is a
well-known method to reduce the amount of scattered x-ray radiation reaching the detector
, thus reducing noise and improving image contrast.
1
. It is rather commonly utilized instead of a conventional grid in plain radiography.
What is high kV technique?
Hence the high kV technique of the chest x-ray is employed to
present a more uniformly dense image to better appreciate the lung markings
. A 15% increase in kV will essentially correlate to an increase in density similar to double the mAs
2
.
