FAQ MARS spectral CT Scanner
The First Human Images from MARS
MARS scanners go beyond the traditional black-and-white CT to produce color images where different materials can be separated. In the images above, metal, soft tissue, fat and bone are all being identified. We have a commercial small bore scanner and are currently developing a human-scale machine.
What is color x-ray?
Color x-ray is where the energy (or color) of the x-rays that pass through the object is measured.
How is measuring the color of the x-ray different from normal x-ray?
Traditional x-ray measures the number of x-rays that have passed through, which gives information about the density of the object. Very dense materials don’t let many x-rays through, less dense objects let more through. Color x-ray can give information about which material an x-ray passed through rather than just its density. That means two objects of similar density but different materials can be distinguished.
How do you make your color images?
We use math algorithms to take the energy information from the color of the x-ray to find the materials present. We create separate image layers for each material. For example, one layer containing only bone, one containing only fat. X-rays don’t have colors that can be seen by the naked eye, so we apply a color (or color range) to each material. We can choose any color, but often we choose to use colors that look similar to what you would expect to see. We then take all the materials and combine them to produce a single color image.
Why is it useful?
Color x-ray provides new diagnostic information. Traditional CT has poor soft tissue contrast, MRI is limited by its resolution. Color x-ray also offers opportunities to use next generation contrast agents such as gold nanoparticles to detect cancer.
The video below shows how a MARS image is made up of multiple material layers. In this case, calcium, fat and soft tissue. It’s because of being able to measure the energy of the photons that the materials can be distinguished and quantified.