著者

石原 謙

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.56, pp.S162, 2018

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<p>従来医療現場では少しでも危険な可能性があれば回避・忌避する習慣が尊重された。人の命や健康を守る立場から当然でありそれ自体は好ましい。20年前の心臓ペースメーカでは、当時の携帯電話からの電波強度で誤動作をすることが実験でたしかめられていた。しかしペースメーカー自体は当時から何重にも安全に作られていた。生存を脅かす機能停止はせぬよう設計されていた。さらにペースメーカのEMI耐性は著しく改善され、10年ほど前からの製品では医療現場を含めた生活圏における無線電波による機能異常は発生していない。PCやタブレット端末などの電波を発するNW機器についても医療機器に致命的障害を与える医療事故は報告されていない。結果としてこの20年、電波干渉による心臓ペースメーカでの死亡事故は起きていない。 病院での入院患者では携帯電話や無線LANが普段以上に有り難い存在となる。家族や友人との会話は回復への大きな励みになるし、治療部位以外は健常で仕事ができる状態の患者にはNWは必須である。 医療用電波を利用したME機器はゾーン設計の元で適切に使用されてはいるものの、無線LANや携帯電話などの無線端末が、利便性が高いために数多く導入され野放し状態に近い。 医療現場における電波利用の実態を調査し、さらに安全に電波利用を推進することが望まれ、管理監督強化ではなく、医療現場の負担を軽減する方向での活用を促進する合理的なガイドラインが望まれる。</p>

著者

竹内 智一 田中 裕幸 藤岡 英二 植野 彰規

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.55, no.6, pp.267-271, 2017-12-10 (Released:2018-03-29)

参考文献数

12

被引用文献数

2

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In this study, we developed a new approach for simultaneous noncontact measurements of electrocardiograms (ECGs) and pulse beats (PBs) using passive and semi-active capacitive-coupling methods. The applicability of this method to blood-pressure (BP) monitoring of subjects in bed was then evaluated. For ECG measurements, two sets of five-layered conductive-cloth electrodes were placed under the subject's upper back and waist. A so-called driven-seat ground (DSG) was adopted for ECG measurements to reduce interference with the PB detection circuit. The DSG signal was fed back to the fifth layer of the electrode. For PB detection, one conductive cloth sheet was placed under the right calf and another under the right heel. The sheets formed capacitive couplings with the body via clothing, and the couplings were incorporated into a multi-vibrator. Changes in the oscillatory frequency of the multi-vibrator caused by PBs were measured as voltage changes. To increase the sensitivity of PB detection under the heel, the sheet area ratio between the calf and the heel was set to 5:1. Seven participants were instructed to lie on a bed in the supine position, and experimental measurements were performed on them. In the experiment, the following procedures were conducted : the subject rested for 20 s;a Valsalva test (VT) was conducted for 15 s;and the subject rested again for 100 s. As reference signals, continuous measurements of BP from the left fingertip, as well as chest ECG and photo-plethysmographic signals from the right fingertip were recorded. For evaluation analysis, all PBs were detected over the 80-second period of the output signals beginning 10 seconds after the end of the VT. As a result, the sensitivity of the PB was 99.2±1.1%. The mean correlation coefficient between the PB arrival time and systolic BP was-0.83±0.15. These results suggest the possibility of using the proposed method for noncontact BP monitoring during rest in bed.

著者

佐藤 正明

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.57, no.4-5, pp.105-112, 2019-09-10 (Released:2019-12-19)

参考文献数

49

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The author has continued to research on cytomechanics since 1983 when he visited Professor Nerem’s laboratory, University of Houston, Texas, USA as a visiting scholar. In those days the effects of shear stress on functions of endothelial cells (EC) are focused from the point of view of atherogenesis. In this review, progress of cytomechanics on EC is mainly summarized. First, the definition and the significance of cytomechanics are introduced. EC are located at the innermost layer of vascular wall and always exposed to three different external forces (i.e. shear stress, cyclic stretch and hydrostatic pressure). These mechanical forces affect the configuration and functions of EC and the cells finally adapt a physical environment. Cultured EC elongates and aligns to direction of flow and the degree of shape change depends on many factors such as animal and cell species, magnitude of shear stress, duration of stimulation, material of substrate and so on. Cytoskeletal structure is also changed prior to change of cell shape. Cyclic stretch induces cell elongation and the orientation transversely to the strain direction. Pressured EC exhibit multilayered structure and marked elongation and orientation with the random direction, together with development of centrally located, thick stress fibers. Mechanical forces stimulate signal transduction, gene regulation, protein synthesis and so on. The details of the time course of responses is summarized in the text. Recent progresses on cytomechanics are two topics as follows. One is an effect of substrate elasticity on differentiation of stem cells. Human mesenchymal stem cells are cultured on three different elastic substrate (i.e. soft, moderate and stiff matrices), and then respectively differentiated into neuron, muscle and bone. Another is discovery of mechanosensing molecule called mechanosensor. Living cells respond to external and internal forces, however, the sensing mechanism is not elucidated yet. Mechanosensors such as stretch-activated channel in cell membrane, p130Cas, α-catenin, talin at cell junctions and stress fiber itself are explained as the typical examples.

著者

堀 拳輔 董 居忠 岡本 啓公 関 将志 村石 浩 齊藤 典生 Thet Thet LWIN 原 秀剛 渡辺 宝 橋本 雄幸 王 波 武田 徹

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.56, no.1, pp.16-21, 2018-02-10 (Released:2018-06-15)

参考文献数

12

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Lung cancer is one of the most important diseases to overcome, and chest radiography and low-dose computed tomography (CT) have been used for lung cancer screening. In chest radiographs, nodules overlying the ribs and mediastinum are occasionally difficult to detect. Therefore, CT is used as the gold standard modality to diagnose lung cancer, despite the high radiation exposure it entails. Recently, tomosynthesis has been used to detect pulmonary nodules, but mechanical scanning and a long data acquisition time (approximately 10 seconds) are required to obtain the image. Under this circumstance, tomosynthesis using a small number of projections has been anticipated to allow omission of the mechanical system and shortening of the exposure time. A chest phantom with artificial pulmonary nodules of various sizes was imaged in rotating 360-degree projections. Tomosynthesis images were reconstructed using back projection (BP) from ±32-degrees projection data, and the projection numbers were set at 4, 6, 8, 16, 32 and 64. The images were evaluated visually and quantitatively by measuring the contrast noise ratio (CNR) and artifact spread function (ASF). Tomosynthesis images reconstructed from 4 projection images allowed visualization of an artificial nodule 10mm in diameter without overlapping the ribs or the mediastinum. The CNR of a 4-projection image normalized to that of a 64-projection image was approximately 0.34, and the ASF obtained indicated that fewer number of projections was associated with greater z-axis resolution. Thus, 4-projection tomosynthesis allows visualization of pulmonary nodules 10mm or larger in diameter, and image quality appears to be useful.

著者

前川 義量 阿部 武志 秋山 庸子 三島 史人 白井 みどり 西嶋 茂宏

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.49, no.6, pp.836-842, 2011-12-10 (Released:2012-04-10)

参考文献数

13

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In the field of nursing care for the elderly persons, understanding of their somatic sensation such as pain is very important for care workers to provide appropriate care. However, it is not always easy for elderly person with declined verbal function. Therefore, the objective evaluation method of pain intensity without verbal communication is required. In this study, pain evaluation system which can be used in daily life without verbal communication was developed. The system is noninvasive, because the information corresponding to pain intensity is extracted from facial expression. In order to digitalize the facial expression, the images of facial expression were extracted from the web cam on real time, and were analyzed sequentially. Pain stimulation test was carried out for healthy adults by dipping their hand into ice water (cold pressor test). A strong correlation was observed for young adults between pain face factor calculated from the facial expression digitalized by the system and sensory evaluation score of pain, VAS value. It indicates the validity of this system for estimation of pain intensity.

著者

江田 英雄 山崎 まどか

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.56, pp.S145, 2018

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<p>非観血的血圧計測手法の標準は水銀柱式血圧計測である。しかし十分に訓練を受けた者か有資格者が計測しなければ、水銀柱血圧計測で信頼しうる血圧値を得ることは困難である。また環境への配慮から水銀を用いない計測装置が必要とされている。一方、光技術を用いて脈波を計測し血圧推定値を計算する手法があり、カフレス連続血圧計の実現に向けて期待されている。本研究では、水銀柱式血圧計と光センサモジュールを同時計測することによって、水銀柱式血圧計測値と、カフレス連続血圧推定値とを比較した。対象は、医療系学科に在籍する大学生、及び、民間企業に在籍する健常人とした。右上腕部に水銀柱式血圧計のマンシェットを巻き、マンシェットの内側に光センサーモジュールを、右上腕動脈が触れる位置近傍に装着・固定した。水銀柱血圧計にて通常の血圧測定を行い、同時に光センサーモジュールによる連続血圧推定値を観察した。連続血圧推定値は加圧の後、減圧後約20秒以内に安定した値を示し、この値を光センサーモジュールによる血圧推定値とした。各被験者に対し、2回血圧測定をして、水銀柱血圧計計測値と光センサーモジュールによる血圧推定値の相関をBland-Altmanプロットで検討した。通常の水銀柱血圧計測で必要とされる安静時の計測では、両者は高い相関を示した。</p>

著者

吉澤 誠 杉田 典大 湯田 恵美 田中 明 本間 経康 山家 智之

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.58, pp.542-543, 2020

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<p>近年,健康管理のためにウェアラブル・センサが普及しつつある.例えば,アップル社のApple Watchの最新バージョンでは,光電脈波計ばかりではなく心電計の機能まで具備している.確かに,ウェアラブル・センサは身体に直接装着するため,常時連続的な生体情報取得が可能である.しかし当然であるが,ウェアラブル・センサは,それを購入して「装着(ウェア)」しなければセンシングできない. 一方,パーソナルコンピュータやスマートフォンに内蔵されているビデオカメラの映像信号から脈波(映像脈波)が得られる.ウェアラブル・センサに比べて映像脈波が決定的に優れているのは,何も身に付けず(ウェア"レス"に),遠隔・非接触的なセンシングができる点である. 本稿では,まず,映像脈波の計測方法とその性質について述べた後,映像脈波の幅広い応用可能性について解説する.すなわち,家庭における風呂・トイレなどでの血圧サージの検出,洗面所の鏡やスマートスピーカーでの応用可能性,あるいは自動車内での運転者のモニタリングについて触れ,最も応用可能性の高いものとして,スマートフォンを使ったクラウドサービスの概念を紹介する. 次に,映像脈波の実用上の課題と限界について述べる.すなわち,映像脈波の最大の弱点が,体動と照度変化に極端に弱いことであり,それぞれに関する対策を紹介するとともに,今後を展望する</p>

著者

山越 健弘 山越 康弘 松村 健太 廣瀬 元

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.47, no.2, pp.154-165, 2009-04-10 (Released:2009-09-09)

参考文献数

37

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Physiological monitoring was carried out during the motor sport of Racing Kart driving. In addition to highlighting the importance of physiological measurement during motor sports, this study may have social relevance through its potential to contribute to decreasing automobile accidents in overload situations by using appropriate biosignals. The measurement quantities collected in this study were instantaneous heart rate, HR, vector magnitude of acceleration, G, blood pressure, BP, and core body temperature, Teardrum. After giving informed consent 11 healthy male subjects (34.4 ± 7.7 S.D. yrs) were tested in the racing circuit. We successfully monitored the physiological variables during karting, finding a statistically significant decrease in BP (p < 0.01) and a rise in Teardrum (p < 0.01) immediately after the driving period. In addition, we have confirmed that HR was maintained at approximately 150bpm, which, by means of time-frequency analysis, could be explained by sympathetic acceleration. Furthermore, it is strongly suggested that the rise in HR could be closely related to the G forces to which the drivers were subjected. These results clearly disclose to us one aspect of the possible physiological responses and the importance of physiological monitoring during motor sports.

著者

山田 正敏 田畑 泰彦

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.43, no.2, pp.238-246, 2005 (Released:2007-01-19)

参考文献数

31

被引用文献数

1

著者

岩田 彰

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.57, no.1, pp.35-36, 2019-03-10 (Released:2019-05-22)

著者

孫 越 マルリン ラマダンバイディラ アルアミン サイクルイマン 川嶋 大介 武居 昌宏

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.55, no.5, pp.389, 2017

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<p>リンパ浮腫治療においてリンパ浮腫の早期発見は重要課題であり、現状、確立された検出法はない。本研究では、リンパ浮腫の早期段階で細胞間質液に現れるアルブミンのよどみを電気的に検出することで、リンパ浮腫を早期発見する「インピーダンス・トモグラフィ法」を提案する。まず、二電極を利用してリンパ浮腫と正常細胞の電気特性を測定し、アルブミンの検出に最適なパラメータを調査した。この結果をもとに、リンパ浮腫の早期状態を模擬した人体ファントムを用いてインピーダンス・スペクトルの多点計測を行い、ファントムの断面分布画像を取得した。得られた画像には、観察断面のアルブミンのよどみ位置が明瞭に現れており、本手法がリンパ浮腫の早期発見手法として利用できる可能性を示した。</p>

著者

梅津 光生 岩﨑 清隆 松橋 祐輝 坪子 侑佑 笠貫 宏

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.57, pp.S11_2, 2019

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<p>講演者が、本会の生田幸士大会長と、「真の医工連携に必要なこと」に関して意見交換したのは、今から10年以上前である。写真だけを見て仲人の勧めを信じて結婚を決意するような「戦前の見合い」方式では、相手のことがわからず、成果が上がらない、やはり、「一つ屋根の下での同棲生活」でお互いが理解でき、成果が上がりやすいのではないか、との結論を得た。そのコンセプトが、早稲田大学と東京女子医科大学の連携施設であるツインズの創設につながっている。しかし、工学研究者が第一線の臨床医と組んで高い技術を造り上げたとしても一般治療として定着するまでには多くのハードルがある。そこを乗り越えるためには十分な科学的根拠を取得することであり、医療レギュラトリーサイエンスという学問が重要となる。2014年制定の「医薬品、医療機器等の品質・有効性・安全性の確保に関する法律」が、5年を経て、新医療機器の迅速な臨床応用に向けて、さらなる法整備が進められている。その流れの中で、実臨床になるべく近い環境を再現した上で、新たな治療の効果と適正な使用法を説明できるような評価系技術の確立がキーとなり、それを体験できる人材の育成を進めている。</p>

著者

上原 皓 河本 浩明 今井 壽正 白井 誠 曾根 政富 野田 幸子 佐藤 栄人 服部 信孝 山海 嘉之

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.57, no.6, pp.206-214, 2019-12-10 (Released:2020-02-29)

参考文献数

34

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Gait festination (GF) is one of the representative locomotion disturbances associated with Parkinsonism, which induces pulsion caused by increased stepping velocity. Fear of falling over and involuntary symptoms caused by GF can have a significant impact on quality of life. Considering previous interventional strategies for GF and their utility in daily life, physical intervention using a wearable system to assist postural disorder and the hastening phenomenon is necessary for patients with GF. The purpose of this study was to develop a wearable system that can assist the patient in extending the trunk and generating internal rhythm. Another objective was to confirm the effectiveness of the system for preventing GF by conducting a gait experiment in a Parkinsonism patient. To design an assistive method, we simulated lateral swing in the standing position based on features of Parkinsonism, and defined the mechanism and power configurations for the system. A power unit at the back of the waist transmits a cyclic force to the chest by a link in the frontal plane. A gait experiment was performed in a Parkinsonism patient with GF to confirm that reduction of the gait cycle is prevented by using the system. The result showed that the linear trendline slope of reduction of the gait cycle decreased. In addition, the maximum stooping angle decreased by half, and the cyclic assistance of the system and gait cycle were harmonized. These results suggest that the system developed is effective in preventing GF by supporting posture and generating internal rhythm.

著者

近藤 悟 長谷川 光司 湯山 一郎

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.51, no.2, pp.149-156, 2013-04-10 (Released:2013-09-10)

参考文献数

9

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The frictional force between a fingertip and a flat surface of an object is not stable and changes each time. We measured the frictional force through rubbing on the surface of acryl plate by fingertip of forefinger of three men and eight women in life environment and reconfirmed that the frictional forces were not stable. Ten of eleven subjects succeeded to evaluate the difficulty to move the finger rubbing on the surface of the plate using a subjective rating scale method in five degrees. A subjective score revealed that the perceived interference was correlated to the magnitude of the frictional force between the finger and the surface. We recognized the sweat on the fingertip according to correlated value of the maximum coefficient of friction in the ten subjects though the sweat on the fingertip was not confirmed visually.

著者

田中 志信 本井 幸介 野川 雅道 山越 健弘 山越 憲一

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.44, no.3, pp.467-474, 2006 (Released:2008-05-01)

参考文献数

18

被引用文献数

1

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The daily monitoring of health conditions at home is a very important subject not only as an effective scheme for the early diagnosis and treatment of cardiovascular and other diseases, but also for the prevention and control of such diseases. From this point of view, we have been developing a fully automated “non-conscious” monitoring system for home healthcare. In this paper, we describe the structural details of a newly developed blood pressure (BP) measurement system built into a toilet seat and some results obtained using the system. The principle used for BP measurement was the volume-oscillometric method. A reflectance-type photoplethysmographic sensor was installed in an appropriate position on the toilet seat, and it was automatically lifted and lowered using a newly designed helicoid-type actuator. Systolic (SBP) and mean BP (MBP) were obtained using the arterial volume pulsation signal obtained by the sensor. In order to evaluate the accuracy of the BP measurements, simultaneous measurements were carried out using two types of commercially available BP monitors (upper arm and wrist). Simultaneous measurement using an “invasive technique” via catheterization to the right brachial artery was also conducted. From the results obtained (bias[s.d.] for SBP; Upper arm: -1.20 [7.90] mmHg, Wrist: 0.44 [7.28] mmHg, Invasive: -0.41 [4.91] mmHg, bias [s.d.] for MBP; Upper arm: 4.40 [6.91] mmHg, Wrist: 5.07 [8.04] mmHg, Invasive: 3.68 [5.69] mmHg), reasonable accuracy of the present system was clearly demonstrated. This system, which requires no cumbersome procedures for BP measurement such as cuff setting, proper positioning of measuring site and so on, appears to be a useful means for long-term home healthcare monitoring.

著者

赤澤 堅造 奥野 竜平 一ノ瀬 智子 竹原 直美 松本 佳久子 中山 実音 益子 務

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.53, no.Supplement, pp.S341-S346, 2015 (Released:2016-06-18)

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We have been developing a novel electronic musical instrument Cymis (Cyber Musical Instrument with Score), showing that persons with neural or motor impairments such as cerebral palsy can play the piece easily. The aim of the present study is to propose a basic idea of prospective music performance on the Cymis which may attenuate cognitive impairment and reduce the risk of dementia in the elderly. In the beginning, we have tried to show that Cymis performance could be an effective cognitive stimulus. Five subjects, university female students majoring music, were instructed to perform a song, keeping the constant tempo, with pointing each head of note displayed on the touch monitor. Two popular songs that they knew well were selected, under the conditions of with and without sound production, and regular tempo of 84[BPM ] and extraordinarily fast tempo of 150[BPM]. By examining both answers to fourteen questions regarding cognitive functions and results of performance, it was indicated that Cymis performace could be an effective stimulus to cognitive function.

著者

斉藤 飛翔 笹川 和彦 森脇 健司 藤崎 和弘

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.57, pp.S143_2, 2019

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<p>血管内治療において,カテーテル挿入手技は医師の経験や指先の感覚に大きく依存し,その感覚を他人に正確に伝えることは難しい.その感覚を提示するため,カテーテルに作用する力を計測するシステムが開発されているが,装置が大掛かりである.また,挿入手技時にカテーテル先端と血管壁の衝突等によって術者が指先で感じる力覚を直接的に計測するものではないことから,手技の可視化を目的とした指先の力覚計測と動作解析を同時に行うシステムの開発要求が強い.本研究では,指先に接着可能なフィルム型3軸応力センサを作製し,指先の応力計測とモーションキャプチャを使った動作解析が可能なカテーテル手技可視化システムの開発を行い,血管モデルにこれを適用して術者の指先の応力計測と動作解析の有効性を検討した.カテーテルが血管壁に衝突しないときと比較し,衝突したときの方が指先の進行方向におけるせん断応力が大きく,また,ねじり動作に応じたねじり方向のせん断応力も計測できた.よって,カテーテルの前進・後退・ねじりの動作に対応した指先の接触応力を検出でき,カテーテル手技可視化の手段として本システムの有用性を示した.</p>

著者

高倉 公朋

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.49, no.3, pp.465-466, 2011-06-10 (Released:2011-12-15)

著者

飯島 淳彦 小杉 剛 木竜 徹 松木 広介 長谷川 功 板東 武彦

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.49, no.6, pp.946-951, 2011-12-10 (Released:2012-04-10)

参考文献数

9

被引用文献数

3

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We investigated an effective method for evaluating chronic stress in humans by using pupillary responses to visual motion stimuli. Nine subjects watched movies including 18 short video movies (duration:10s in each). The pupil diameter responding to the movies were measured with a video oculography and calculated the difference between the maximum and minimum pupil diameters responded to the stimuli was highly correlated with the salivary α-amylase (R=-0.76, p=0.018) activities. The sympathetic nervous system is activated by a stress and secretes the salivary amylase. We found that there were some autonomic different responses in the stress subject from pupillary and salivary observations. These phenomena were clearly observed under the visual movie stimulation which was able to reveal the steady pupillary responses.

著者

城屋敷 健志 和田 親宗

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.56, no.2, pp.44-51, 2018-04-10 (Released:2018-10-18)

参考文献数

21

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Body-conducted sound sensors have an electret condenser microphone with an exposed diaphragm. By covering the sensor with a urethane elastomer, the sensor can be used as a bioacoustic sensor with high sensitivity and resistance to external noise. The body-conducted sound sensors constructed in the past had different parameters such as contact area, thickness of the propagation layer and mass, and the extent of their influence on frequency characteristics is unclear. This study aimed to investigate the influence of the mass and shape of body-conducted sound sensor on pressure sensitivity. The methods comprised ( 1 ) simulation using the equivalent circuit model, ( 2 ) production of body-conducted sound sensors and measurement systems, and ( 3 ) sensitivity measurements and analyses. The simulation results demonstrated that the sensitivity increased when the body-conducted sound sensor had a small mass and a large contact area. In the sensitivity measurement system, a compact acceleration sensor was used as a reference sensor, and the sensitivity to pressure was calculated. The results obtained from the sensitivity measurement system correlated strongly with the frequency characteristics of the simulations, with a correlation coefficient of 0.90-0.95 in the frequency range of 100-2,000Hz. In the statistical analysis, by varying the mass and contact area, significant differences were observed in the frequency range of 700-2,000Hz while no significant differences were observed in the frequency range of 100-600Hz. Moreover, as a result of reducing the housing mass, sensitivity was increased. In conclusion, body-conducted sound sensors with a small mass and large contact area exhibit high pressure sensitivity in the frequency range of 700-2,000Hz, and their frequency characteristics can be estimated by simulation.