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Dec 11, 2019

The Leadership Interview: CEO Spencer Gunn

- By Jacqueline Wheeler

CEO Spencer Gunn took Direct Conversion from loss to a value of 75 million Euros in only five years. He achieved this rapid growth by concentrating the company’s expertise on developing and producing easy-to-use, easy-to-integrate, high performance X-ray detectors for the medical and NDT industries.  

This year, Direct Conversion was acquired by leading innovator in the field of X-ray component manufacturing, Varex Imaging.  We caught up with Spencer as he prepared for RSNA 2019.

 Why is photon counting such a valuable technology? 

The data gathered from this technology is quantitative and the pixel values reflect the actual number of photons detected. The images generated by our detectors provide our users with the opportunity to extract more information about the object being examined. 

How has Direct Conversion made photon counting more accessible?  

We are the first company to bring affordable photon counting to the mass market so that it can be used in hospitals and clinics where high levels of safety are required but a manageable cost is desirable to keep the system price down. 

Our ASIC (developed by CTO Christer Ullberg), the CMOS that does the actual counting, is a mature product and has been field proven in many applications, from mammography to CT. Its broad range of applications means we manufacture high volumes and can therefore keep our prices affordable.  

What applications are the photon counting detectors best suited to?

Our detectors are especially useful if one is trying to identify and separate different materials in the object being X-rayed. The high sensitivity and high efficiency of direct conversion detectors also makes them the ideal choice for very high energy imaging, where electronic scatter rejection is essential. 

What are the advantages of your detectors for medical applications? 

Efficiency. The thickness of the convertor allows us to stop more X-rays without loss of resolution and this means low dose imaging with high resolution images. This is very important for mammography, of course, as healthy women are irradiated during a scan and the dose needs to be as low as reasonably achievable. 

For CT, the same applies; we can capture more of the X-rays, in generalgreater efficiency leads to the same signal in a shorter time. Photon counting energy discrimination means CT reconstructions can be improved too, as well as opening up a whole new field of multispectral CT which we will see emerge in the next 5 to 10 years. Direct Conversion already has a breast CT customer who has launched a system employing our sensors in a curved array and this validates our technology in a real world, CE marked device. 

Now you are part of Varex, how will your detectors fit into their packaged solutions for CT? 

Varex currently supplies many of the parts for X-ray imaging in a CT system, but it doesn’t have a CT detector.  With our technology, Varex will be able to expand these supplied components by adding a detector sub-system fully assembled and ready for use to plug into the rest of the CT system. 

What are the advantages of joining the Varex team?          

Direct Conversion will benefit from Varex’s global presence and a team of experts who understand X-ray and how we can help improve safety and patient care. Direct Conversion will be able to access this pool of talent and build on its success to push photon counting into the mainstream. 

Speak to CEO Spencer Gunn about our technology at Direct Conversion, Booth 2973