The Clinical Trials Act introduced in Japan in April 2018 requires measures to ensure the safety of subjects. As defined in the act, the term “clinical trials” refers to such research that is conducted to clarify an efficacy or safety of medicines, medical devices, and medical instrument by testing them in people, that is, by using them in a medical practice. If a research is recognized as a clinical trial, the act requests judicious procedure to conduct the research. However, the definition of medical practice has not been interpreted systematically. Therefore, medical-engineering researchers have difficulty in deciding whether their study involves a medical practice. As a result, the act may cause reduction of researches in biomedical engineering. Here, we try to clarify the principles used to decide whether a research is classified as a “clinical trial” and to provide a summary for medical-engineering researchers as a guideline of the Japanese Society for Medical and Biomedical Engineering. We apply the guideline to several examples to show its efficiency.
Studies about electrical current passing through the body such as bioelectricity measurement, electrical excitation, and electrical stimulus have contributed to the field of medical and biological engineering. To evaluate the applicability of the Clinical Trials Act, stimulus conditions are needed to be designed based on the understanding of safety criteria provided by various organizations, as well as the effects of the electricity applied to the human body. Because electrical current causes various effects such as perception, pain, injury, and fibrillation, safety design is essential. This paper summarizes the effects and safety criteria of the electricity applied to the human body based on the available guidelines. Furthermore, effects and criteria of the electricity applied to the head are discussed. Finally, we present an example of the stimulus evaluation to confirm the applicability of the Clinical Trials Act.
We have conducted extraction of three-dimensional blood vessel structure by spatial extension of ultrasonic 3D images (volumes) aiming to develop ultrasound therapy. However, since acquisition of the image depended on the sense of the operator, improvement of the interface was required. In addition, verification of the effectiveness of the method has not been done in human blood vessels, including deformation of blood vessels by posture and breathing. Therefore, we propose a three-dimensional extension method of the blood vessel network by connecting multiple ultrasound volumes acquired from different directions. The information of the three-dimensional structure of blood vessel extracted from the B-mode image and Doppler signal was converted into a tree structure graph containing information of the centerline and the bifurcation points. Then we developed an interface by obtaining position and posture information of the probe measured using position measuring tracker attached to the probe, calculated the homogeneous transformation matrix, and displayed multiple volumes acquired at different timings in the same coordinate system. Furthermore, by performing spatial registration, common bifurcation points were extracted from multiple tree structure graphs to extend the blood vessel network spatially. Using the liver blood vessels in healthy persons, we succeeded to obtain a wide area of vascular networks reaching the right and left lobes. Furthermore, we confirmed that the blood vessel network structure was preserved during changes of posture and respiratory state, and validated the effectiveness of our three-dimensional extension method.
This article reports on the 2019 annual meeting of the Committee for Promotion of Strategic International Standardization of Non-Invasive Cardiovascular Monitors. This committee consists of mainly members from industries interested in manufacturing cuffless blood pressure monitors. The aim of the committee is to organize meetings and encourage draft standards from committee members for use by international organizations. During the meetings, advice is given by policymakers and professionals working in the digital medicine and healthcare fields. In 2019, we reviewed the Institute of Electric and Electronic Engineers (IEEE) 1708a-2019 standard for wearable, cuffless blood pressure measuring device, and the International Standards Organization Draft International Standard (ISODIS) 81060-3 for non-invasive sphygmomanometers. We discussed and evaluated these standards with committee members. The IEEE1708a-2019 standard is not accepted by Japanese regulatory body. Based on ISODIS 81060-3, a subcommittee was formed to evaluate the current embedded cuffless blood pressure monitors based on mobile devices by collection of basic accuracy data. Additionally, Pharmaceuticals and Medical Devices Agency (PMDA) and Food and Drug Administration (FDA) recommendations were evaluated, and advocacy of the importance of cuffless blood pressure monitors was conducted to regulatory bodies and academic societies. Based on these activities, we are in a position to create new standards for blood pressure monitors.