Neue CT-Generation: photonenzählende Detektortechnik

Photonenzählende Detektoren (PZD) sind die aktuellste Entwicklung in der CT. Die Vorteile im Vergleich zu den klassischen energieintegrierenden Detektoren (EID) liegen im reduzierten elektronischen Rauschen, der höheren Ortsauflösung, dem erhöhten Kontrast-Rausch-Verhältnis und einer besseren Dosiseffizienz. Zusätzlich kann der Einsatz von Kontrastmitteln reduziert werden. In diesem Artikel werden die technischen Grundlagen erläutert.

Abstract

Photon counting detectors (PCD) are a recent development in computed tomography (CT) and represent a promising new technology. This technique has been used in nuclear medicine during the past years, but at relatively low photon count rates. However, recent developments in semiconductor technology have enabled the use in computed tomography. PCD are direct conversion detectors and they separate the incoming photons into different energy levels. The advantages compared to classic energy-integrating detectors (EID) are reduced electronic noise, higher spatial resolution, increased contrast-to-noise ratio and better dose efficiency. At the same time, energy-resolved image data can be acquired, which can reduce the use of contrast media. PCD-CT have the potential to significantly influence routine clinical diagnostics, which is why the technical principals for radiology technologists are explained in this article.

Schlüsselwörter

photonenzählende Detektoren - CT - Photonen - energieintegrierende Detektoren

Key word

photon counting detector - computed tomography - photons - energy-integrating detector

Publication History

Article published online:
27 September 2022

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