Digital imaging techniques were implemented in the 1970′s with the first clinical use and acceptance of the Computed Tomography or CT scanner, invented by Godfrey Hounsfield. Analog to digital converters and computers were also adapted to conventional fluoroscopic image intensifier/TV systems in the 70′s as well.
Angiographic procedures for looking at the blood vessels in the brain, kidneys, arms and legs, and the blood vessels of the heart all have benefited tremendously from the adaptation of digital technology as discussed on, http://xraytechnicianeducation.com, a leading xray career site. Over the next ten to fifteen years a large majority of conventional x-ray systems will also be upgraded to all digital technology.
An intermediate technology called, phosphor plate technology is currently available at hundreds of medical science sites around the world. These plates trap the x-ray energy and require an intermediate processing step to release the stored information so it can be converted into a digital picture.
Benefits of digital technology to all x-ray systems:
- less x-ray dose can often be used to achieve the same high quality picture as with film
- digital images can be retrieved from an archive at any point in the future for reference.
- digital images can be archived onto compact optical disk or digital tape drives saving tremendously on storage space and manpower needed for a traditional x-ray film library
- digital x-ray images can be enhanced and manipulated with computers
- digital images can be sent via network to other workstations and computer monitors so that many people can share the information and assist in the diagnosis
Some imaging scanning sciences like mammography require extremely high-resolution film to show the smallest breast cancers. Digital detectors capable of a similarly high resolution are under development and will hopefully be available in the near future. However, digital imaging is already being used in parallel to high-resolution film in breast imaging and breast biopsy systems.
Nuclear Medicine studies also called radionuclide scanning, were first done in the 1950s using special gamma cameras. Nuclear medicine studies require the introduction of very low-level radioactive chemicals into the body. These radionuclides are taken up by the organs in the body and then emit faint radiation signals, which are measured or detected by the gamma camera.
In the 1960′s the principals of sonar, which were developed extensively during the Second World War, were applied to diagnostic imaging. The process involved placing a small device called a transducer, against the skin of the patient near the region of interest, for example, the kidneys or other internal organs.
This transducer produced a stream of inaudible, high frequency sound waves, which penetrated into the body and bounced off the organs inside. The transducer detected sound waves as they bounced off or echoed back from the internal structures and contours of the organs.
These waves were then received by the ultrasound machine and turned into live pictures with the use of computers and reconstruction software. Today, one of the most popular uses of ultrasound scanning is to diagnose the fetal status for pregnant women.