Publications by authors named "M M Paulides"
Introduction: This study evaluated the performance of magnetic resonance thermometry (MRT) during deep-regional hyperthermia (HT) in pelvic and lower-extremity soft-tissue sarcomas.
Materials And Methods: 17 pelvic (45 treatments) and 16 lower-extremity (42 treatments) patients underwent standard regional HT and chemotherapy. Pairs of double-echo gradient-echo scans were acquired during the MR protocol 1.
Article Synopsis
- Magnetic resonance thermometry (MRT) allows real-time, non-invasive measurement of temperature changes in the oropharynx and head and neck, but motion during long treatments may create artifacts.
- This study evaluated MRT's feasibility for hyperthermia treatments by analyzing its performance during breath-hold and swallowing scans on five volunteers over approximately 75 minutes.
- Results showed no significant differences in MRT performance due to breathing or swallowing, but indicated that different regions of interest (ROI) had varying accuracy, with neck muscle performing best in terms of mean average error (MAE) and standard deviation (SD).
Hyperthermia treatment consists of elevating the temperature of the tumor to increase the effectiveness of radiotherapy and chemotherapy. Hyperthermia treatment planning (HTP) is an important tool to optimize treatment quality using pre-treatment temperature predictions. The accuracy of these predictions depends on modeling uncertainties such as tissue properties and positioning.
View Article and Find Full Text PDFA crucial aspect of quality assurance in thermal therapy is periodic demonstration of the heating performance of the device. Existing methods estimate the specific absorption rate (SAR) from the temperature rise after a short power pulse, which yields a biased estimate as thermal diffusion broadens the apparent SAR pattern. To obtain an unbiased estimate, we propose a robust frequency-domain method that simultaneously identifies the SAR as well as the thermal dynamics.
View Article and Find Full Text PDFPurpose: To compare different thermal tissue models for head and neck hyperthermia treatment planning, and to assess the results using predicted and measured applied power data from clinical treatments.
Methods: Three commonly used temperature models from literature were analysed: "constant baseline", "constant thermal stress" and "temperature dependent". Power and phase data of 93 treatments of 20 head and neck patients treated with the HYPERcollar3D applicator were used.