The External Structure of the X-ray Tube
The x-ray tube and housing assembly are quite heavy, and therefore require a support mechanism so that the radiologic technologist can position it.
Ceiling Support Systems
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| Floor-to-Cieling Support System |
Cieling Support System ( Del Medical) The ceiling support system is probably the most frequently used. It consist of 2 perpendicular sets of ceiling-mounted rails. This allows for both longitudinal and transverse travel of the x-ray tube. The ceiling support system has a telescoping column attaches the x-ray tube housing to the rails, allowing for adjustment of SID (Source-to-image receptor distance).
Floor-to-ceiling Support System
The Floor to ceiling support system has a single column with rollers at each end, one attached to a ceiling mounted rail and the other attached to a floor mounted rail. The tube slides up and down the column as the column rotates. A varation of this type of support system has the column positioned on a single floor support system using one or two floor mounted rails.
C-arm Support System
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| Shimadsu - Floor Support System |
Interventional radiology suites often are equipped with C-arm support systems, so called because the system is shaped like a letter “C”. These system are ceiling mounted and provide for very flexible x-ray tube positioning. The image receptor is attached to the other end of the C-arm from the x-ray tube. Variations called L-arm or U-arm support are also common.
Protective Housing
The Protective Housing guards against excessive radiation exposure and electrical shock. When x-rays are produced, they are emitted isotopically, that is with equal intensity in all directions. We use only those emitted though the special section of the x-ray tube called the window. Those x-rays emitted through the window are called the useful beam. The protective housing incorporate specially designed high-voltage receptacles to protect against accidental electrical shocks. Death by electrocution was a very real hazard to early radiologic technologist. It also provides a mechanical support for the x-ray tube and protects the tube from damage caused by rough handling.
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| C-arm Support System |
Glass or Metal Exposure
An x-ray tube is an electronic vacuum tube with componets contained within a glass or metal enclosure. The glass enclosure is made of Pyrex glass to enable it to withstand the tremendous heat generated. The Metal enclosure tubes maintains a constant electric potential between the electrons of the tube current and enclosure. The enclosure maintains a vacuum inside the tube to allow more efficient x-ray production and longer tube life. Usually all current high-capacity x-ray tube use metal enclosures.
