Overview
IEC TS 63070:2019 is a technical specification published by the International Electrotechnical Commission (IEC), focusing on ultrasonics and field characterization using infrared imaging techniques. This specification provides methods for evaluating temperature elevation in tissue-mimicking materials (TMM) and at the radiating surface of ultrasonic transducers in still-air conditions. Its main purpose is to guide accurate temperature measurements for both diagnostic and therapeutic ultrasonic medical equipment, including physiotherapy and high intensity therapeutic ultrasound (HITU) devices.
Infrared imaging, when applied according to this standard, enables both qualitative and quantitative assessment of thermal effects caused by ultrasound absorption in tissue-equivalent phantoms and by self-heating of the transducer. The results are crucial for validating device safety, supporting regulatory compliance, and improving the effectiveness of ultrasonic medical devices.
Key Topics
- Infrared Imaging Techniques: The document details the use of infrared (IR) cameras for temperature measurement. Requirements include specific temperature ranges, spatial resolution, nominal temperature resolution, and regular calibration against primary standards.
- Tissue-Mimicking Material (TMM) Phantom: A split phantom design allows for precise temperature mapping immediately after insonation. The specification covers construction, material properties (emissivity, thermal conductivity, attenuation), and periodic validation.
- Transducer Surface Temperature Measurement: Methods are provided for assessing the surface temperature of the ultrasound transducer in still air, aligning with regulatory safety requirements.
- Measurement Procedures: Outlined step-by-step approaches for both split TMM and still-air setups, with emphasis on environmental control, emissivity settings, and minimizing external thermal interference.
- Uncertainty Determination: Guidance is given for estimating and reducing measurement uncertainty using customary analysis methods, supporting confidence in results.
- Calibration and Validation: The importance of annual calibration of IR cameras and regular phantom validation to guarantee ongoing measurement accuracy.
Applications
IEC TS 63070:2019 is valuable in multiple practical contexts:
- Medical Device Testing: Supports manufacturers and testing laboratories in characterizing thermal effects during pre-market evaluation of ultrasonic diagnostic and therapeutic equipment.
- Quality Assurance: Facilitates routine checks and quality control processes for hospitals and clinical engineering departments to ensure ongoing device safety.
- Research and Development: Assists researchers developing new ultrasound modalities or refining instrumentation by providing reproducible procedures for thermal mapping and transducer assessment.
- Regulatory Compliance: Fosters conformity with international safety requirements cited in IEC 60601-2-37, IEC 60601-2-5, and IEC 60601-2-62 standards, often referenced in global medical device regulations.
Related Standards
Stakeholders using IEC TS 63070:2019 should also consider the following related standards for comprehensive compliance and best practices:
- IEC 60601-2-37: Medical electrical equipment - Safety and performance for ultrasonic medical diagnostic and monitoring equipment.
- IEC 60601-2-5: Safety and performance for ultrasonic physiotherapy equipment.
- IEC 60601-2-62: Safety and performance for high intensity therapeutic ultrasound (HITU) equipment.
- IEC 61161: Ultrasonics - Power measurement using radiation force balances.
- IEC 62127-1: Measurement and characterization of medical ultrasonic fields (hydrophones).
- ISO 18434-1: Condition monitoring and diagnostics of machines - Thermography procedures.
Conclusion
IEC TS 63070:2019 presents a comprehensive framework for infrared imaging-based temperature measurement in tissue-mimicking material and at ultrasonic transducer surfaces. By adhering to this specification, users in the medical ultrasonics field can achieve high-quality, traceable thermal characterization, supporting both device innovation and patient safety. Integration of the outlined methodologies helps ensure devices meet global standards and regulatory expectations, further promoting best practices in medical ultrasonics.