Imaging small animals with positron emission tomography

Summary

During the past few years many research centers have successfully applied their knowledge of positron emission tomography (PET) to construct PET scanners which are dedicated to image small animals such as rats and mice. Although there are many in-house built systems which are used in laboratory environments, only a few of them are commercially available at this time. This review will give an overview of dedicated animal PET systems with their technical description and main physical characteristics. Graphical analysis of spatial resolution against absolute sensitivity allows a comparison of the most important characteristics of each camera.

The quadHIDAC, a PET scanner recently installed at the Department of Nuclear Medicine, University Hospital Münster, acquires images with sub-millimeter spatial resolution. A ¹⁸F-FDG whole body image of a mouse with small structures like the left ventricle of the heart clearly visualized, demonstrates its excellent spatial resolution.

Zusammenfassung

Einige Forschungseinrichtungen benutzten in den vergangenen Jahren erfolgreich ihre Expertise auf dem Gebiet der Positronenemissionstomographie (PET) dazu, PET Scanner für den Einsatz bei kleinen Tieren, wie Ratten und Mäusen, zu entwickeln. Obwohl es eine Vielzahl solcher experimenteller Kameras gibt, sind zurzeit nur wenige kommerziell erhältlich. Diese Übersicht stellt aktuelle Kleintier-PET-Kameras mit einer Beschreibung des jeweiligen Systems einschl. seiner physikalischen Eigenschaften vor. Eine graphische Darstellung von räumlicher Auflösung gegenüber absoluter Sensitivität stellt die wichtigsten Systemeigenschaften vergleichend dar.

Der quadHIDAC-PET-Scanner ist ein System, das kürzlich in der Klinik und Poliklinik für Nuklearmedizin, Universitätsklinikum Münster installiert wurde, mit der Möglichkeit, Bilder mit einer räumlichen Auflösung unter einem Millimeter zu akquirieren. Eine Ganzkörperaufnahme (¹⁸F-FDG) von einer Maus, bei der selbst kleinste Strukturen wie der linke Ventrikel des Herzens sichtbar sind, demostriert die exzellente räumliche Auflösung.

Keywords

Positron emission tomography - animal - molecular imaging

Schlüsselwörter

Positronenemissionstomographie - Kleintier-PET - molekulare Bildgebung

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