Precision of the PET activity range during irradiation with10C,11C, and12C beams

D Kostyleva; S Purushothaman; P Dendooven; E Haettner; H Geissel; I Ozoemelam; C Schuy; U Weber; D Boscolo; T Dickel; V Drozd; C Graeff; B Franczak; C Hornung; F Horst; E Kazantseva; N Kuzminchuk-Feuerstein; I Mukha; C Nociforo; S Pietri; C A Reidel; H Roesch; Y K Tanaka; H Weick; J Zhao; M Durante; K Parodi; C Scheidenberger

doi:10.1088/1361-6560/aca5e8

Precision of the PET activity range during irradiation with¹⁰C,¹¹C, and¹²C beams

Phys Med Biol. 2022 Dec 19;68(1). doi: 10.1088/1361-6560/aca5e8.

Authors

D Kostyleva¹, S Purushothaman¹, P Dendooven², E Haettner¹, H Geissel^{1

3}, I Ozoemelam⁴, C Schuy¹, U Weber¹, D Boscolo¹, T Dickel^{1

3}, V Drozd^{1

5}, C Graeff¹, B Franczak¹, C Hornung¹, F Horst¹, E Kazantseva¹, N Kuzminchuk-Feuerstein¹, I Mukha¹, C Nociforo¹, S Pietri¹, C A Reidel¹, H Roesch^{1

6}, Y K Tanaka⁷, H Weick¹, J Zhao^{1

8}, M Durante^{1

9}, K Parodi¹⁰, C Scheidenberger^{1

3

11}

Affiliations

¹ GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany.
² Particle Therapy Research Center (PARTREC), Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
³ II. Physikalisches Institut, Justus-Liebig-Universität, Gießen, Germany.
⁴ Fontys University of Applied Sciences, Eindhoven, The Netherlands.
⁵ Faculty of Science and Engineering, University of Groningen, Groningen, The Netherlands.
⁶ Institute for Nuclear Physics, Technische Universität Darmstadt, Darmstadt, Germany.
⁷ RIKEN Cluster for Pioneering Research, Wako, Japan.
⁸ School of Physics, Beihang University, Beijing, People's Republic of China.
⁹ Department of Condensed Matter Physics, Technische Universität Darmstadt, Darmstadt, Germany.
¹⁰ Department of Physics, Ludwig-Maximilians Universität München, Munich, Germany.
¹¹ Helmholtz Forschungsakademie Hessen für FAIR (HFHF), Campus Gießen, Gießen, Germany.

PMID: 36533621
DOI: 10.1088/1361-6560/aca5e8

Abstract

Objective. Beams of stable ions have been a well-established tool for radiotherapy for many decades. In the case of ion beam therapy with stable¹²C ions, the positron emitters^10,11C are produced via projectile and target fragmentation, and their decays enable visualization of the beam via positron emission tomography (PET). However, the PET activity peak matches the Bragg peak only roughly and PET counting statistics is low. These issues can be mitigated by using a short-lived positron emitter as a therapeutic beam.Approach.An experiment studying the precision of the measurement of ranges of positron-emitting carbon isotopes by means of PET has been performed at the FRS fragment-separator facility of GSI Helmholtzzentrum für Schwerionenforschung GmbH, Germany. The PET scanner used in the experiment is a dual-panel version of a Siemens Biograph mCT PET scanner.Main results.High-quality in-beam PET images and activity distributions have been measured from the in-flight produced positron emitting isotopes¹¹C and¹⁰C implanted into homogeneous PMMA phantoms. Taking advantage of the high statistics obtained in this experiment, we investigated the time evolution of the uncertainty of the range determined by means of PET during the course of irradiation, and show that the uncertainty improves with the inverse square root of the number of PET counts. The uncertainty is thus fully determined by the PET counting statistics. During the delivery of 1.6 × 10⁷ions in 4 spills for a total duration of 19.2 s, the PET activity range uncertainty for¹⁰C,¹¹C and¹²C is 0.04 mm, 0.7 mm and 1.3 mm, respectively. The gain in precision related to the PET counting statistics is thus much larger when going from¹¹C to¹⁰C than when going from¹²C to¹¹C. The much better precision for¹⁰C is due to its much shorter half-life, which, contrary to the case of¹¹C, also enables to include the in-spill data in the image formation.Significance. Our results can be used to estimate the contribution from PET counting statistics to the precision of range determination in a particular carbon therapy situation, taking into account the irradiation scenario, the required dose and the PET scanner characteristics.

Keywords: PET; carbon ions; particle therapy; radioactive ion beams; range verification.

Creative Commons Attribution license.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Germany
Half-Life
Phantoms, Imaging
Positron-Emission Tomography* / methods