Photon-counting CT opens doors in oncology imaging


The ability of radiologists at the University Hospital Pilsen to observe tumor development and metastasis in cancer patients has taken a leap forward, according to radiologist Professor Jiří Ferda.1

High resolution, low-dose, spectral imaging – these are the main three benefits of the photon-counting CT scanner NAEOTOM Alpha, according to Jiří Ferda, Chair of the Department of Imaging, University Hospital Pilsen. He performed his first human scan using a prototype of the system in June 2020. And he continues to be amazed at what photon-counting CT can do.

NAEOTOM Alpha is now used daily in clinical routine at the University Hospital Pilsen. Most important of all the new features, in Professor Ferda’s view, is the increased spatial resolution. It is now possible to identify small anatomical structures, conduct more detailed vascular imaging and detect and observe tumor development and potential metastasis. For CT angiography in tumors, Ferda and his team generally reconstruct at a standard slice thickness of 0.8 or 0.6 millimeters and a matrix of 512x512. If need be, they can go as low as 0.2 millimeters and increase the matrix to 1024x1024.  

Examples of the successful application of such ultra-high-resolution imaging in Ferda’s department include carotid paraganglioma (neck), rectosigmoid carcinoma (intestine) and renal cell carcinoma (kidney).

Ferda highlights another benefit when it comes to treatment: “It is important to know if a therapy drug injected into the venous system can pass into the tumor itself. With ultra-high spatial resolution, we can clearly see it.”1

Another feature of the new generation of CT is its wide range of options enabled by spectral imaging. Ferda highlights the now inherently obtained virtual non-contrast and iodine maps in every image taken, which help in diagnosis and therapy, but also spare the patient additional screenings and unnecessary radiation exposure. Depending on the type of screening, up to one third of contrast agent can be avoided, says the expert.1 

And there is another major improvement when it comes to cancer therapy. Ferda mentions that with the photon-counting CT, vascular mimicry – a technique of many tumors to form their own microvascular channels – can be observed more clearly than before. “It is a very important behavior of some tumors which sometimes can be seen on early artery scans but often is only seen in much later phases. Now we can detect it much earlier.” 1

“The photon-counting CT opens doors which before were closed for us,” Ferda says. “Even at low doses, it is able to operate more efficiently and with more detail than all previous CT machines.” 1

Florian Bayer, journalist in Vienna