Adaptive ultrasound temperature imaging for monitoring radiofrequency ablation
| Autor: | Qiang Li, Chia-Yen Lee, Po-Hsiang Tsui, Yi-Da Liu, Yao-Wen Yeah, Chien-Cheng Chang, Zhuhuang Zhou |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Hot Temperature
Radiofrequency ablation Swine medicine.medical_treatment Echoes lcsh:Medicine 01 natural sciences Biochemistry Thermal expansion 030218 nuclear medicine & medical imaging law.invention Diagnostic Radiology 0302 clinical medicine law Thermocouple Speed of sound Ultrasound Imaging Medicine and Health Sciences Tissue Distribution lcsh:Science 010301 acoustics Ultrasonography Multidisciplinary Radiology and Imaging Physics Applied Mathematics Simulation and Modeling Liver Diseases Ultrasound Ablation Transducer Thermocouples Oncology Physical Sciences Catheter Ablation Engineering and Technology Step detection Algorithms Research Article Materials science Imaging Techniques Equipment Gastroenterology and Hepatology Research and Analysis Methods Carcinomas 03 medical and health sciences Diagnostic Medicine 0103 physical sciences Gastrointestinal Tumors medicine Animals Pharmacokinetics Measurement Equipment Pharmacology business.industry lcsh:R Biology and Life Sciences Cancers and Neoplasms Acoustics Hepatocellular Carcinoma Models Theoretical Gastrointestinal Imaging lcsh:Q business Mathematics Liver and Spleen Scan Biomedical engineering |
| Zdroj: | PLoS ONE PLoS ONE, Vol 12, Iss 8, p e0182457 (2017) |
| ISSN: | 1932-6203 |
| Popis: | Radiofrequency ablation (RFA) has been widely used as an alternative treatment modality for liver tumors. Monitoring the temperature distribution in the tissue during RFA is required to assess the thermal dosage. Ultrasound temperature imaging based on the detection of echo time shifts has received the most attention in the past decade. The coefficient k, connecting the temperature change and the echo time shift, is a medium-dependent parameter used to describe the confounding effects of changes in the speed of sound and thermal expansion as temperature increases. The current algorithm of temperature estimate based on echo time shift detection typically uses a constant k, resulting in estimation errors when ablation temperatures are higher than 50°C. This study proposes an adaptive-k algorithm that enables the automatic adjustment of the coefficient k during ultrasound temperature monitoring of RFA. To verify the proposed algorithm, RFA experiments on in vitro porcine liver samples (total n = 15) were performed using ablation powers of 10, 15, and 20 W. During RFA, a clinical ultrasound system equipped with a 7.5-MHz linear transducer was used to collect backscattered signals for ultrasound temperature imaging using the constant- and adaptive-k algorithms. Concurrently, an infrared imaging system and thermocouples were used to measure surface temperature distribution of the sample and internal ablation temperatures for comparisons with ultrasound estimates. Experimental results demonstrated that the proposed adaptive-k method improved the performance in visualizing the temperature distribution. In particular, the estimation errors were also reduced even when the temperature of the tissue is higher than 50°C. The proposed adaptive-k ultrasound temperature imaging strategy has potential to serve as a thermal dosage evaluation tool for monitoring high-temperature RFA. |
| Databáze: | OpenAIRE |
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