From the Research
A whole spine CT scan typically delivers a radiation dose of approximately 6-10 millisieverts (mSv), though this can vary based on the specific protocol, equipment used, and patient factors. This is roughly equivalent to 2-3 years of natural background radiation exposure. Modern CT scanners often employ dose reduction techniques such as iterative reconstruction algorithms and automatic exposure control to minimize radiation while maintaining diagnostic image quality, as discussed in a recent systematic review on acquisition and reconstruction techniques to reduce radiation dose in spinal CT examinations 1. The radiation dose is higher than conventional X-rays but provides significantly more detailed information about bone and soft tissue structures.
While this level of radiation carries a small theoretical increased risk of cancer, the clinical benefit typically outweighs this risk when the scan is medically necessary. Patients should discuss any concerns about radiation exposure with their healthcare provider, especially if they've had multiple imaging studies or are pregnant. Alternative imaging options like MRI might be considered in certain cases, particularly for non-emergency situations or when radiation exposure is a significant concern. It's also worth noting that recent studies have explored the feasibility of sub-milliSievert scanning protocols for whole spine CT scans, particularly in pediatric patients, with promising results in terms of diagnostic image quality and reduced radiation dose 2.
Some key factors that can influence the radiation dose of a whole spine CT scan include:
- The specific protocol used, such as the tube potential, reference mAs, and convolution filter
- The equipment used, such as the type of CT scanner and its capabilities for dose reduction
- Patient factors, such as body size and composition
- The use of dose reduction techniques, such as iterative reconstruction algorithms and automatic exposure control.
Overall, the estimated radiation dose of a whole spine CT scan can vary, but it is generally in the range of 6-10 mSv, and efforts should be made to minimize radiation exposure while maintaining diagnostic image quality, as emphasized in recent reviews on CT radiation dose and its gentle and wise use 3.