Radio daignosis

Researches shows that Medical tests such as X-rays, CT scans and PET scans are vital tools for diagnosing diseases. Because While there are numerous benefits to these types of tests;therefore  they can expose patients to higher than normal doses of radiation. Exposure to too much radiation from medical imaging can increase the risk of cancer; which can limit how often patients can be tested.

CT scans and PET scans

However; a new study led by The Australian National University (ANU) has found a way to greatly lower X-ray doses, potentially making them cheaper and safer and improving early detection of diseases like breast cancer. The research team; which has involved the European Synchrotron Radiation Facility and Monash University; has built upon an unconventional approach known as ‘ghost imaging’.

A key aspect of the technique is that most of the X-ray dose is not directed towards the object. Instead; the measurements are computed by shining light on to the object in different patterns. “You’re computing what the object looks like based on a set of measurements;” said Dr Andrew Kingston from the ANU Research School of Physics and Engineering.

Object in different patterns

“If you already know; more or less, what the object should look like, then you only need to take enough measurements to see how it’s different from what you expect rather than having to image it from zero knowledge.” The concept of ghost imaging; although having been around since 1995; was only first demonstrated with X-rays in 2016 and has just now been extended to 3D-imaging.

Ghost tomography can be carried out by applying 2D ghost imaging to an object at many angles and then using standard tomography techniques to create a 3D image from all the ghost projections. But the team showed that method didn’t work very well using the data they collected.

Demonstrated with X-rays

“We developed a technique to reconstruct the 3D data directly from the measurements rather than computing the projection images at each angle and then computing the 3D image, which actually didn’t give us anything useful,” Kingston said. “We discovered that by directly computing the 3D image from measured data, we could recover an image of the object because we are using the data more effectively.”
In a world first, the team has extended a 2D concept to obtain a 3D image of the interior of objects that are opaque to visible light. This involved taking a 3D ghost image of a 5.6 mm diameter object at a low resolution of about 0.1 mm, using the new measurement system with a series of patterned X-ray beams.