How Low-Dose CT Scanning Prolongs X-ray Tube Lifespan
Of the different CT scanner components that must be replaced over time, the X-ray tube is often the most expensive—so it is no surprise that facilities using CTs are eager to prolong their lifespan however possible. Several factors contribute to X-ray tubes’ aging, but the most fundamental driving factor is heat: X-ray tubes operate at high temperatures and energy levels, and this puts their components at risk of failure and gradual wear and tear. Heat’s harmful impact on X-ray tubes can be seen in the anode, anode bearings, cathode filament, and tube vacuum envelope.
In a typical high-voltage CT scan, the anode current increases with the cathode filament temperature, which in turn decreases the filament lifespan. The higher the anode current, the shorter the filament life and the greater the thermal stress on the anode. On the other hand, reducing the anode current alleviates some of these effects. Lower anode currents also reduce bearings temperatures, prolonging their lives as well.
While some of heat’s effects are inevitable (after all, X-rays will always require some level of heat), addressing this root cause of X-ray tubes’ decline can dramatically increase their lifespans. In practical terms, that means reducing the X-ray tubes’ power and energy requirements, and thereby decreasing the minimum operating temperature. One way to accomplish this is to lower the radiation dose used in procedures like CT scanning.
Why focus on CT scanning? Along with nuclear imaging, it is one of the main sources of US patients’ increasing exposure to radiation in medical treatments. Because they use as much as 70 times the radiation of a conventional chest X-ray, reducing the dose used in CT scans by even a small percentage could significantly decrease the total amount of radiation used—and thereby extend X-ray tube lifespan. One study found that some CT scan system owners who used low-dose protocols were able to conduct between 40% and 400% more scans before replacing their X-ray tubes. These extra scans extended their tubes’ useful lives far beyond the lifespan estimated by the tubes’ manufacturers.
Reducing X-ray dose in CT scanning does not have to be expensive, nor does it necessarily involve purchasing a new CT scanner. Add-on technologies exist that make it possible to use the same equipment with reduced radiation dose. For example, PixelShine® software uses machine learning to reduce inherent image noise during CT scans, allowing images produced with low doses of radiation to match the quality of those made with higher doses. This type of artificial intelligence technology is available for older legacy CT scanners to ensure that they can continue producing usable, high-quality scans for a longer time before requiring replacement parts.
Newer scanners can also benefit from technologies like PixelShine, which makes it possible to reduce the amount of radiation used for most CT scans, thereby reducing wear and tear for many years to come and cutting facilities’ spending on costly consumables. In addition to improving patient safety , using creative methods like PixelShine to reduce radiation dosages is a smart investment to take full advantage of medical equipment and maximize its useful life.