Final answer:
A posteroanterior (PA) X-ray is performed with the X-ray beam passing from back to front. CT scans can offer more detailed imaging with cross-sectional views by using multiple X-ray projections and computer processing. Safety measures, including lead aprons, are important to minimize radiation exposure during X-ray imaging.
Step-by-step explanation:
To perform a posteroanterior (PA) X-ray, the X-ray beam would pass through the body from the posterior (back) to the anterior (front). The patient stands facing a flat surface that holds the X-ray film or digital detector, with their back to the X-ray tube. For this procedure, the X-ray source is positioned behind the patient, and the X-ray detectors are positioned in front of the patient. Dense bones or other structures can obscure softer tissue in standard two-dimensional X-rays, but techniques such as computed tomography (CT) scans provide a more detailed view by taking multiple images around the body part. These images can be further processed for enhanced detail or to generate three-dimensional reconstructions. Notably, protective measures such as a lead apron should be used to limit exposure to radiation, while fast films and proper positioning can reduce the duration of exposure. CT scans in particular involve a series of rotating X-ray captures and complex computer image processing to produce highly detailed images of cross-sectional slices of the body. G. Hounsfield and A. Cormack's development of this technology earned them the Nobel Prize in Medicine in 1979.