Ads
related to: patient positioning for x ray
Search results
Results from the WOW.Com Content Network
Image-guided radiation therapy (IGRT) is the process of frequent imaging, during a course of radiation treatment, used to direct the treatment, position the patient, and compare to the pre-therapy imaging from the treatment plan. [1]
However, in case the patient cannot stand, the radiograph often needs to be taken with the patient lying in a supine position (called a "bedside" radiograph) with the X-rays coming from above ("anteroposterior" or "AP"), and geometric magnification will then cause for example the heart to appear larger than it actually is because it is further ...
Many patient positioning devices have been developed for this purpose, including masks and cushions which can be molded to the patient. Image-guided radiation therapy is a method that uses imaging to correct for positional errors of each treatment session.
A radiation source is positioned behind the patient at a standard distance (most often 6 feet, 1,8m), and the x-ray beam is fired toward the patient. In anteroposterior (AP) views, the positions of the x-ray source and detector are reversed: the x-ray beam enters through the anterior aspect and exits through the posterior aspect of the chest.
A Settegast is a standard medical x-ray projection that presents a tangential view of the patella. To acquire such an image the patient is placed in a prone position with the knee flexed at least 90 degrees and the field of view centered on the patellofemoral joint space.
The radiograph for each mastoid is taken separately. Schuller's view serves as an alternate view to the Law projection which uses a 15° angle of patient's face toward the image receptor and a 15° caudal angulation of the computed radiography (CR) to achieve the same result, a lateral mastoid air cells view without overlap of the opposite side.
An illustration of the heel effect in an x-ray tube. In X-ray tubes, the heel effect or, more precisely, the anode heel effect is a variation of the intensity of X-rays emitted by the anode depending on the direction of emission along the anode-cathode axis. X-rays emitted toward the anode are less intense than those emitted perpendicular to ...
The gantry of an external beam radiotherapy machine moves a radiation source around a patient. A linear accelerator (linac) is built into the top part of the gantry in the photo at the right. The rectangular screen on the right side of the gantry is a cone beam x-ray detector, which is used to help position a patient prior to treatment.
Ads
related to: patient positioning for x ray