Bedeutung der Dosimetrie aus Sicht des Nuklearmediziners

Zusammenfassung

Auch wenn bei der Radionuklidtherapie die individuelle Dosimetrie unter Mitwirkung des Medizin-Physik-Experten in der Strahlenschutzverordnung (StrSchV) festgeschrieben ist, bestehen unterschiedliche Auffassungen über das Ausmaß der Datenerfassung und auch technische Limitationen im Hinblick auf eine valide Bildgebung zur Bestimmung der Biokinetik. Dabei ist für die klinische Anwendung stets eine einfache und robuste Approximation zu bevorzugen.

Für wissenschaftliche Fragestellungen und für die Berücksichtigung der biologisch effektiven Dosis bedarf es jedoch valider Algorithmen, insbesondere für die Kombination interner und externer Radiotherapie. Die Anwendung von Alphastrahlern mit geringen Aktivitätsmengen und geringer Emissionswahrscheinlichkeit von Gammastrahlung zur Bilderzeugung zwingt jedoch teilweise, auf Standardaktivitätsmengen auszuweichen oder sich an Wirkung und Nebenwirkung analog zu anderer onkologischer Systemtherapie zu orientieren.

Abstract

Even though individual dosimetry (with the assistance of a medical physics expert) is stipulated in the Radiation Protection Ordinance (Strahlenschutzverordnung, StrSchV) for radionuclide therapy, there are different perceptions regarding the extent of data acquisition as well as the technical limitations keeping in mind visual imaging valid to determine the biokinetics. For clinical applications, always a simple approximation is preferred.

For scientific questions and considering the biological effective dose, valid algorithms are required, especially for the combination of internal and external radiotherapy. However, the application of alpha emitters with small amounts of activity and a low gamma yield for imaging partially demands switching to standardized activities or an orientation based on the clinical effect and corresponding side effects analogously to other oncological systemic therapies.

Schlüsselwörter

Dosimetrie - Nebenwirkungen - biologisch effektive Dosis - Biokinetik

Keywords

dosimetry - side effects - biologic effective dose - biokinetics

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