Cadmium Zinc Telluride: The wonder material powering a medical 'revolution'

Summary

'It's amazing' – the wonder material very few can makeChris BaraniukTechnology ReporterKromekVery few organisations can supply cadmium zinc tellurideLying on your back in a big hospital scanner, as still as you can, with your arms above your head – for 45 minutes. It doesn't sound much fun.That's what patients at Royal Brompton Hospital in London had to do during certain lung scans, until the hospital installed a new device last year that cut these examinations down to just 15 minutes.It is partly thanks to image processing technology in the scanner but also a special material called cadmium zinc telluride (CZT), which allows the machine to produce highly detailed, 3D images of patients' lungs."You get beautiful pictures from this scanner," says Dr Kshama Wechalekar, head of nuclear medicine and PET. "It's an amazing feat of engineering and physics."The CZT in the machine, which was installed at the hospital last August, was made by Kromek – a British company. Kromek is one of just a few firms in the world that can make CZT. You may never have heard of the stuff but, in Dr Wechalekar's words, it is enabling a "revolution" in medical imaging.This wonder material has many other uses, such as in X-ray telescopes, radiation detectors and airport security scanners. And it is increasingly sought-after.Investigations of patients' lungs performed by Dr Wechalekar and her colleagues involve looking for the presence of many tiny blood clots in people with long Covid, or a larger clot known as a pulmonary embolism, for example.The £1m scanner works by detecting gamma rays emitted by a radioactive substance that is injected into patients' bodies.But the scanner's sensitivity means less of this substance is needed than before: "We can reduce doses about 30%," says Dr Wechalekar. While CZT-based scanners are not new in general, large, whole-body scanners such as this one are a relatively recent innovation.Guy's and St Thomas' NHS Foundation TrustDr Kshama Wechalekar with the late...