MXR Imaging acquired Oxford Instrument Healthcare in May 2020

Why Allowing Your CT Scanner to Warm Up Before Use is Beyond Critical

Why It's Necessary to Let Your CT Scanner Warm Up Before Using It

CT scanners are expensive pieces of equipment. Even repairing or replacing its components can be very costly, which is why you'll want to not only maintain your CT scanner properly but that you operate it according to OEM recommendations  in order to avoid damage caused by misuse. For example, one of the most important--and expensive--components of a CT scanner is the X-ray tube. To help preserve your scanner's X-ray tube and to prolong their life, always let your CT scanner warm up before use. If you don't let it warm up properly, it could result in wear and tear that will shorten your X-ray tube's life, cause damage that requires repairs, or cause the tube to fail completely, thereby requiring replacement.

What is a “CT Scanner Warm Up Sequence”

X-ray tubes work by converting electrical input power into X-rays, which means they are vital to your CT scanner's ability to capture diagnostic images. It also means they require a lot of energy to perform their function, and consequently produce a lot of heat. If the tube's anode is cold, this production of heat can cause serious damage. It would be the equivalent of taking cookware out of the freezer and placing it in a hot oven--it would crack almost immediately due to the sudden change in temperature. However, if that cookware were warmed up at a slower rate, this wouldn't happen. The same applies to X-ray tubes.

To help prevent the sudden change of temperature from damaging the X-ray tubes, CT scanners are built with warm-up sequences. By performing a proper warm-up sequence, you'll gradually warm up the tube so it's ready to be used to capture an actual X-ray. Unfortunately, not all CT technicians perform proper warm-up procedures when they should--even though many manufacturers even apply decals that describe the correct warm-up procedure on the generator console itself. Not only should a warm-up sequence be performed when the CT scanner is first turned on, but it should also be performed if a few hours pass between scanning procedures, since the tube will have cooled down drastically over the course of this period.

It Increases The Life Of Your Tubes

X-ray tubes generally last two to three years depending on the wear and tear they experience. If you don't do proper warm-up procedures, they'll be much more likely to fail before then. In fact, one of the main reason X-ray tubes fail and require replacement is due to issues caused by overheating. Although a high heat load on a warm tube is not likely to cause any damage, a high heat load on a cold tube will. Even if it doesn't cause the tube to fail, it can cause enough wear and tear on the tube that it will be more prone to failure eventually, especially if you continue operating your CT scanner without warming it up when needed.

It Reduces Risk of Failure

Overheating your X-ray tubes can cause them to fail prematurely, but it can also result in other problems that cause errors in operating your CT scanner. For example, arc errors can occur due to too much electrical arcing in the tube. This can cause a CT scan to be interrupted in the middle of a scanning procedure. X-ray tubes are built to tolerate a certain amount of electrical arcing, but if the tube was cold and wasn't properly warmed up, an arc error can result in an immediate shutdown of the system.

Reduces Downtime

Warm-up procedures do not take a long time to complete. Considering how long your CT scanner can be out of commission should your X-ray tube suddenly fail, it's well worth taking the time to make sure the tubes are properly warmed up before you begin a scheduled scan.

Down time can wreak all manner of havoc. If your CT scanner has failed, a repair technician will need to do a thorough inspection of the CT scanner to determine if your X-ray tube is the issue. Once properly diagnosed, the tube may need to be replaced, in which case a new tube will have to be ordered. All of this takes time, during which you will not be able to use your CT scanner. Even if your tube is still in working condition, shutdowns caused by arcing errors can delay your scanning schedule.

Warm-up sequences can help reduce down time, which will allow you to image patients when they're scheduled instead of having to delay their scans or referring them to a different facility. Down time can be especially disruptive if your CT scanner is being used for emergency purposes.

Replacement Parts and Servicing Are Expensive

X-ray tubes are incredibly expensive--they can set you back as much as $200,000. They're generally only available from your OEM (original equipment manufacturer) as well since they are built specifically for the CT scanner you have. While the cost of regular tube replacement (around every three years if your CT scanner is properly maintained) should be included in your budget, the unplanned replacement of a damaged tube can cause a serious hit to your budget.

What if Your CT Scanner Cannot Warm Up?

Proper warm-up procedures should be provided by the manufacturer of your CT scanner. Always follow their instructions to warm up your CT scanner when needed to prevent potential damage to your X-ray tubes and to prevent operational failure. If the CT scanner was turned off, a warm-up sequence should be initiated when it's turned on. If the scanner goes for two hours without being used, a warm-up sequence should again be performed before the next scheduled scan.

CT scanners that run continuously, such as those located in emergency rooms, still need to be warmed up on a regular interval, such as once a day at a specific time. If you're having trouble initiating the system's warm-up sequence, contact a service tech right away. Don't continue running the warm-up sequence in the hopes that it will execute properly--doing so could cause damage to the scanner.