Characterization and clinical evaluation of a novel 2D detector array for conventional and flattening filter free (FFF) IMRT pre-treatment verification
Background and purpose: The novel MatriXXFFF (IBA Dosimetry, Germany) detector is a new 2D ionization chamber detector array designed for patient specific IMRT-plan verification including flattening-filter-free (FFF) beams. This study provides a detailed analysis of the characterization and clinical...
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| Main Authors: | , , , , , , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
2018
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| In: |
Zeitschrift für medizinische Physik
Year: 2018, Volume: 28, Issue: 2, Pages: 134-141 |
| ISSN: | 1876-4436 |
| DOI: | 10.1016/j.zemedi.2017.08.003 |
| Online Access: | Verlag, Volltext: http://dx.doi.org/10.1016/j.zemedi.2017.08.003 Verlag, Volltext: http://www.sciencedirect.com/science/article/pii/S0939388917300466 
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| Author Notes: | Yuvaraj Sekar, Johannes Thoelking, Miriam Eckl, Irakli Kalichava, Dwi Seno Kuncoro Sihono, Frank Lohr, Frederik Wenz, Hansjoerg Wertz |
| Summary: | Background and purpose: The novel MatriXXFFF (IBA Dosimetry, Germany) detector is a new 2D ionization chamber detector array designed for patient specific IMRT-plan verification including flattening-filter-free (FFF) beams. This study provides a detailed analysis of the characterization and clinical evaluation of the new detector array. Material and methods: The verification of the MatriXXFFF was subdivided into (i) physical dosimetric tests including dose linearity, dose rate dependency and output factor measurements and (ii) patient specific IMRT pre-treatment plan verifications. The MatriXXFFF measurements were compared to the calculated dose distribution of a commissioned treatment planning system by gamma index and dose difference evaluations for 18 IMRT-sequences. All IMRT-sequences were measured with original gantry angles and with collapsing all beams to 0° gantry angle to exclude the influence of the detector's angle dependency. Results: The MatriXXFFF was found to be linear and dose rate independent for all investigated modalities (deviations ≤0.6%). Furthermore, the output measurements of the MatriXXFFF were in very good agreement to reference measurements (deviations ≤1.8%). For the clinical evaluation an average pixel passing rate for γ(3%,3mm) of (98.5±1.5)% was achieved when applying a gantry angle correction. Also, with collapsing all beams to 0° gantry angle an excellent agreement to the calculated dose distribution was observed (γ(3%,3mm)=(99.1±1.1)%). Conclusions: The MatriXXFFF fulfills all physical requirements in terms of dosimetric accuracy. Furthermore, the evaluation of the IMRT-plan measurements showed that the detector particularly together with the gantry angle correction is a reliable device for IMRT-plan verification including FFF. |
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| Item Description: | Available online 11 October 2017 Gesehen am 02.07.2018 |
| Physical Description: | Online Resource |
| ISSN: | 1876-4436 |
| DOI: | 10.1016/j.zemedi.2017.08.003 |