NMPA published “Clinical Evaluation Guideline on Medical Imaging Ultrasonic Diagnostic Equipment with the Same Variety” on January 19, 2021. The 27-page document provides manufacturers detailed pathway for clinical evaluation, which is less time-consuming and more cost-effective than clinical trial.
The guideline refers to FDA guidance of “Marketing Clearance of Diagnostic Ultrasound Systems and Transducer and Applying Human Factors and Usability Engineering to Medical Devices.
This Guideline applies to the Class II and III imaging diagnostic ultrasonic equipment, including two-dimensional gray scale imaging system (commonly known as “black and white ultrasound”) and color Doppler blood flow imaging system (commonly known as “color ultrasound”).
The applicants shall conduct the clinical evaluation with the method of same variety comparison, based on the Guideline Basic Principles of Clinical Evaluation of Medical Devices.The differences to the predicate equipment shall be provided to demonstrate that the safety and effectiveness of the declared product are not impacted by the differences.
What Excludes the Pathway
It is not suitable to take an approved device as predicate if one of the following situations occurs:
- It adopts different working principles, imaging modes/functional core algorithms, such as ordinary B-mode imaging and plane-wave B-mode imaging
- It has different technical characteristics, which have a great impact on the device performance, application or operation, such as: automatic breast scanning with robotic arm linear array probe and hand-held linear array probe scanning breast by doctors;
- It is used in different clinical applications, such as abdomen and heart.
- Different clinical information is provided, such as providing strain ratio and Young’s modulus.
Example of Difference Demonstration
If differences occur, the evidences can be provided to show the differences do not affect the safety and efficacy, for example,
- If there are certain differences in key performance parameters, but the product design is basically equivalent to the predicate, and there is no significant impact on quality or the part of the difference can be fully demonstrated by non-clinical research data, and the clinical application is relatively mature, manufacturers can consider providing engineering test and phantom research data or one or several types of animal experiment data.
- If the difference of the product involves major changes in product design or key performance parameters (such as changes in the imaging modes/functions supported by the probe, the number of focal points changes from a few to no focal points, etc.), or it cannot be fully proven as safe and effective through non-clinical evidence, based on phantom research data or animal experiment data, manufacturers can consider providing five to eight cases of human body image sample data for the smallest evaluation unit, each subject can scan multiple parts and pattern combinations.