Abstract
Clinical outcome of hyperthermia depends on the achieved target temperature, therefore target conformal heating is essential. Currently, invasive temperature probe measurements are the gold standard for temperature monitoring, however, they only provide limited sparse data. In contrast, magnetic resonance thermometry (MRT) provides unique capabilities to non--invasively measure the 3D--temperature. This study investigates MRT accuracy for MR--hyperthermia hybrid systems located at five European institutions while heating a centric or eccentric target in anthropomorphic phantoms with pelvic and spine structures. Scatter plots, root mean square error (RMSE) and Bland–Altman analysis were used to quantify accuracy of MRT compared to high resistance thermistor probe measurements. For all institutions, a linear relation between MRT and thermistor probes measurements was found with R2 (mean ± standard deviation) of 0.97 ± 0.03 and 0.97 ± 0.02, respectively for centric and eccentric heating targets. The RMSE was found to be 0.52 ± 0.31 °C and 0.30 ± 0.20 °C, respectively. The Bland--Altman evaluation showed a mean difference of 0.46 ± 0.20 °C and 0.13 ± 0.08 °C, respectively. This first multi--institutional evaluation of MR-hyperthermia hybrid systems indicates comparable device performance and good agreement between MRT and thermistor probes measurements. This forms the basis to standardize treatments in multi--institution studies of MR--guided hyperthermia and to elucidate thermal dose--effect relations.
| Original language | English |
|---|---|
| Article number | 1709 |
| Number of pages | 19 |
| Journal | Cancers |
| Volume | 11 |
| Issue number | 11 |
| DOIs | |
| Publication status | Published - 2 Nov 2019 |
Funding
Funding: This work was performed within the framework of COST Action EMF‑MED, and COST Action MYWAVE, supported by COST (European Cooperation in Science and Technology); and financially supported by unrestricted grants of the Dutch Cancer Society KWF‑DDHK 2013‑6072, Pyrexar Medical Corp. and Dr. Sennewald Medizintechnik GmbH. Conflicts of Interest: Dr. Curto reports grants from Pyrexar Medical Corp., grants from COST, during the conduct of the study; Mr. Mulder reports grants from Dutch Cancer Society, during the conduct of the study; Mr. Lamprecht reports grants from Sennewald, during the conduct of the study; grants from Elekta, grants from Siemens, outside the submitted work; Dr. Peller reports grants from Dr. Sennewald Medizintechnik GmbH, outside the submitted work; Dr. Lindner reports grants from Sennewald Medizintechnik GmbH, during the conduct of the study; Dr. Fietkau reports personal fees from Sennewald GmbH, during the conduct of the study; grants and personal fees from Merck Serono, grants and personal fees from Astra Zenica, grants and personal fees from MSD, personal fees from Novocure, personal fees from Brainlab, personal fees from Fresenius Kabi, personal fees from Bristol Byers Squibb, outside the submitted work; Dr. Zips reports financial support from Dr. Sennewald for educational events, during the conduct of the study; grants from Elekta, grants from Siemens, outside the submitted work; Dr. Paulides reports grants from Dutch Cancer Society, during the conduct of the study; Dr. van Rhoon reports grants from Dutch Cancer Society grant KWF‑DDHK 2013‑6072, grants from Pyrexar Medical Corp., during the conduct of the study; grants from Sensius BV, outside the submitted work. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.
Keywords
- Anthropomorphic phantom
- Magnetic resonance imaging--guided hyperthermia
- Magnetic resonance thermometry
- Quality assurance
- Radiofrequency hyperthermia
- Thermistor probe
