X-ray machines are all large devices that can only image hard structures such as bone, unless a contrast-enhancing solution such as barium is present in the patient ... right? Well, no, not all of them. A new system developed by researchers at MIT and Massachusetts General Hospital is small enough to be considered portable, doesn't expose patients to as much radiation, and can image soft tissues in minute detail.
Ordinarily, X-ray machines emit beams of electromagnetic radiation from a single source. The experimental new machine, however, utilizes "a nanostructured surface with an array of tiny tips," each one of those micron-sized tips emitting its own beam of electrons. Those beams pass through a microstructured plate, and are converted into X-rays.
The resulting wider, more even spread of beams is what makes it possible for the machine to image soft tissues, without the need for contrast agents – such solutions take time to inject or administer orally, and some of them can be potentially harmful to the patient.
Additionally, unlike a conventional thermionic X-ray machine, the new device can be quickly turned on and off without needing time to heat up. This should minimize the amount of radiation received by the patient.
The current prototype is reportedly about the size of a shoebox, making it quite portable – production models are expected to be even smaller. This means that they could be used in the field for things like inspecting the integrity of composite materials, or checking carry-on baggage at airports.
According to senior researcher Luis Velásquez-García, the system "could potentially improve the resolution of X-ray imagery by a factor of 100 with hardware that costs orders of magnitude less." The technology still needs to be developed for two to three years, however, with commercialization taking a few years longer.