Nano-Computed Tomography: Technique and Applications

Abstract

Nano-computed tomography (nano-CT) is an emerging, high-resolution cross-sectional imaging technique and represents a technical advancement of the established micro-CT technology. Based on the application of a transmission target X-ray tube, the focal spot size can be decreased down to diameters less than 400 nanometers (nm). Together with specific detectors and examination protocols, a superior spatial resolution up to 400 nm (10 % MTF) can be achieved, thereby exceeding the resolution capacity of typical micro-CT systems. The technical concept of nano-CT imaging as well as the basics of specimen preparation are demonstrated exemplarily. Characteristics of atherosclerotic plaques (intraplaque hemorrhage and calcifications) in a murine model of atherosclerosis (ApoE _(-/-)/LDLR_(-/-) double knockout mouse) are demonstrated in the context of superior spatial resolution in comparison to micro-CT. Furthermore, this article presents the application of nano-CT for imaging cerebral microcirculation (murine), lung structures (porcine), and trabecular microstructure (ovine) in contrast to micro-CT imaging. This review shows the potential of nano-CT as a radiological method in biomedical basic research and discusses the application of experimental, high resolution CT techniques in consideration of other high resolution cross-sectional imaging techniques.

Key Points:

• Nano-computed tomography is a high resolution CT-technology for 3D imaging at sub-micrometer resolution.

• The technical concept bases on a further development of the established ex-vivo-micro-CT technology.

• By improvement of the spatial resolution, structures at a cellular level become visible (e.g. osteocyte lacunae).

Citation Format:

• Kampschulte M, Langheinirch AC, Sender J et al. Nano-Computed Tomography: Technique and Applications. Fortschr Röntgenstr 2016; 188: 146 – 154

Zusammenfassung

Die Nanocomputertomografie (Nano-CT) repräsentiert eine noch junge, hochauflösende Schnittbildtechnologie und stellt eine technische Weiterentwicklung der seit Längerem etablierten Mikrocomputertomografie (Mikro-CT) dar. Durch Einsatz einer Transmissionsröhre, deren Röntgenfokusgröße unterhalb von 400 Nanometer (nm) liegt sowie geeigneter Detektoren und Untersuchungsprotokolle, übertrifft die Nano-CT das räumliche Auflösungsvermögen der klassischen Mikro-CT und ermöglicht eine Ortsauflösung von bis zu 400 nm (10 % MTF). Exemplarisch werden technisches Konzept der Nano-CT Bildgebung (Strahlen- und Bildentstehung) sowie Grundlagen der Probenmontage vorgestellt. Am Beispiel eines Atherosklerose-Modells, der ApoE_(-/-)/LDLR_(-/-)-Doppel-Knockout-Maus, werden Merkmale atherosklerotischer Plaque, d. h. kalzifizierte sowie hämorrhagische Veränderungen im Kontext der hohen Ortsauflösung und im Vergleich zur Mikro-CT demonstriert. Des Weiteren wird die Anwendung der Nano-CT zur Visualisierung der Mikrozirkulation des zerebralen Kortex (Maus), der Strukturdarstellung des Lungenparenchyms (Schwein) und des strukturellen Aufbaus von Knochentrabekeln (Schaf) in Abgrenzung zur Mikro-CT vorgestellt. Die vorliegende Übersichtsarbeit zeigt das Potenzial der Nano-CT als radiologische Methode in der biomedizinischen Grundlagenforschung und diskutiert die Nutzung hochauflösender, experimenteller CT Techniken unter Berücksichtigung alternativer Schnittbildverfahren.

Key words

nano-CT - vasculature - bone - 3 D imaging

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