First experimental time-of-flight-based proton radiography using low gain avalanche diodes

Creative Commons Attribution license..

Objective.Ion computed tomography (iCT) is an imaging modality for the direct determination of the relative stopping power (RSP) distribution within a patient's body. Usually, this is done by estimating the path and energy loss of ions traversing the scanned volume utilising a tracking system and a separate residual energy detector. This study, on the other hand, introduces the first experimental study of a novel iCT approach based on time-of-flight (TOF) measurements, the so-called Sandwich TOF-iCT concept, which in contrast to any other iCT systems, does not require a residual energy detector for the RSP determination.Approach.A small Sandwich TOF-iCT demonstrator was built based on low gain avalanche diodes (LGADs), which are 4D-tracking detectors that allow to simultaneously measure the particle position and time-of-arrival with a precision better than 100μm and 100 ps, respectively. Using this demonstrator, the material and energy-dependent TOF was measured for several homogeneous PMMA slabs in order to calibrate the acquired TOF against the corresponding water equivalent thickness (WET). With this calibration, two proton radiographs (pRads) of a small aluminium stair phantom were recorded at MedAustron using 83 MeV and 100.4 MeV protons.Main results.Due to the simplified WET calibration models used in this very first experimental study of this novel approach, the difference between the measured and theoretical WET ranged between 37.09% and 51.12%. Nevertheless, the first TOF-based pRad was successfully recorded showing that LGADs are suitable detector candidates for Sandwich TOF-iCT.Significance.While the system parameters and WET estimation algorithms require further optimization, this work was an important first step to realize Sandwich TOF-iCT. Due to its compact and cost-efficient design, Sandwich TOF-iCT has the potential to make iCT more feasible and attractive for clinical application, which, eventually, could enhance the treatment planning quality.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:69

Enthalten in:

Physics in medicine and biology - 69(2024), 7 vom: 28. März

Sprache:

Englisch

Beteiligte Personen:

Ulrich-Pur, Felix [VerfasserIn]
Bergauer, Thomas [VerfasserIn]
Galatyuk, Tetyana [VerfasserIn]
Hirtl, Albert [VerfasserIn]
Kausel, Matthias [VerfasserIn]
Kedych, Vadym [VerfasserIn]
Kis, Mladen [VerfasserIn]
Kozymka, Yevhen [VerfasserIn]
Krüger, Wilhelm [VerfasserIn]
Linev, Sergey [VerfasserIn]
Michel, Jan [VerfasserIn]
Pietraszko, Jerzy [VerfasserIn]
Rost, Adrian [VerfasserIn]
Schmidt, Christian Joachim [VerfasserIn]
Träger, Michael [VerfasserIn]
Traxler, Michael [VerfasserIn]

Links:

Volltext

Themen:

059QF0KO0R
4D-tracking
Ion computed tomography
Journal Article
Low gain avalanche diode
Proton therapy
Protons
Sandwich TOF-iCT
Time-of-flight
Water

Anmerkungen:

Date Completed 29.03.2024

Date Revised 29.03.2024

published: Electronic

Citation Status MEDLINE

doi:

10.1088/1361-6560/ad3326

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM369609018