Oyo Electrical Co

Kyoto, Japan

Oyo Electrical Co

Kyoto, Japan
SEARCH FILTERS
Time filter
Source Type

Breban S.,French Institute of Health and Medical Research | Padilla F.,University Pierre and Marie Curie | Fujisawa Y.,Doshisha University | Mano I.,Oyo Electrical Co | And 5 more authors.
Bone | Year: 2010

The aim was to evaluate a new ultrasound device in a young adult population and to assess its reproducibility via comparison to DXA measurements and geometrical measurements from high-resolution radiographs.Ninety-three subjects aged between 20 and 51years were recruited and divided into four groups according to their gender and physical activity status: 22 male athletes, 19 male controls, 21 female athletes, and 31 female controls. Ultrasonic measurements were assessed by the prototype LD-100 (Oyo Electric Co., Kyoto, Japan) on the dominant distal radius. Attenuation in the radius (dB), cortical bone thickness (mm), radius thickness (mm), mass density of cancellous bone (mg/cm3), and elasticity (GPa) of cancellous bone were obtained. BMD was measured by DXA at the dominant distal radius. Radius images were obtained with a direct high-resolution digital X-ray device (BMA, D3A Medical Systems), and radius and cortical thicknesses were estimated using a specific software (ImageJ®, Bethesda, USA), in an area site-matched with LD-100.There was a significant positive correlation between site-matched BMD measurement and LD-100 parameters (p<0.004), X-ray radius thickness, and LD-100 parameters except elasticity (p<0.05, r>0.32), X-ray cortical thickness and LD-100 attenuation and cortical thickness (p<0.01). A significantly higher attenuation, cortical and radius thicknesses were found in athletes compared to controls (p<0.05). The radius thickness measured on radiographs was significantly higher in athletes versus controls in both sexes, and cortical thickness was significantly higher in male athletes versus controls.These data suggest a positive influence of physical activity on bone cortical measurements. This study also confirmed the particular interest of bone assessment by ultrasound. © 2010 Elsevier Inc.


Mano I.,Doshisha University | Horii K.,Oyo Electrical Co. | Hagino H.,Tottori University | Miki T.,Izumiotsu Municipal Hospital | And 2 more authors.
Journal of Medical Ultrasonics | Year: 2015

Purpose: To verify the measurement of cortical bone thickness at the distal radius in vivo using an ultrasonic method. Methods: The method for estimating cortical bone thickness was derived from experiments with in vitro bovine specimens. Propagation time of echo waves and propagation time of slow waves were used for the estimation. The outside diameter of cortical bone and the cortical bone thickness at the distal 5.5 % site of radius were measured with the new ultrasonic bone measurement system, and the results were compared with X-ray pQCT clinical measurements. Results: There was a high positive correlation (r: 0.76) between the cortical bone thickness measured by the new ultrasonic system and the X-ray pQCT results. Conclusion: We will be able to measure not only cancellous bone density but also cortical bone thickness in vivo using ultrasonic waves (without X-ray) safely and repeatedly. © 2015, The Japan Society of Ultrasonics in Medicine.


PubMed | Izumiotsu Municipal Hospital, Oyo Electrical Co., Doshisha University and Tottori University
Type: Journal Article | Journal: Journal of medical ultrasonics (2001) | Year: 2015

To verify the measurement of cortical bone thickness at the distal radius in vivo using an ultrasonic method.The method for estimating cortical bone thickness was derived from experiments with in vitro bovine specimens. Propagation time of echo waves and propagation time of slow waves were used for the estimation. The outside diameter of cortical bone and the cortical bone thickness at the distal 5.5 % site of radius were measured with the new ultrasonic bone measurement system, and the results were compared with X-ray pQCT clinical measurements.There was a high positive correlation (r: 0.76) between the cortical bone thickness measured by the new ultrasonic system and the X-ray pQCT results.We will be able to measure not only cancellous bone density but also cortical bone thickness in vivo using ultrasonic waves (without X-ray) safely and repeatedly.


Sai H.,Kobe University | Iguchi G.,Kobe University | Tobimatsu T.,Kobe University | Takahashi K.,Kobe University | And 8 more authors.
Osteoporosis International | Year: 2010

A reference database for trabecular bone density, cortical thickness, and elastic modulus of trabecular bone for a novel ultrasonic bone densitometry system (LD-100) based on two longitudinal waves (fast and slow) was determined over a wide age range in a normal Japanese population. Introduction: A novel ultrasonic bone densitometry system (LD-100 system) was applied to create a reference database for trabecular bone density (TBD), cortical thickness (CoTh), and elastic modulus of trabecular bone (EMTb) for this device over a wide age range in a normal Japanese population. Methods: In a comparative study between LD-100 and peripheral quantitative computed tomography (pQCT) systems, 52 individuals were examined by both systems at the same radius simultaneously. To create a reference database, a total of 2,380 healthy subjects (1,179 men, 1,201 women), ages 18-99 years, were examined using the LD-100 system. Results: Highly significant correlations between the LD-100 and pQCT systems were found in TBD (r = 0.877, p < 0.001) and CoTh (r = 0.723, p < 0.001). For the reference database, peak values of TBD, CoTh, and EMTb were observed at 30-34 years (255.09 mg/cm3), 20-24 years (5.23 mm), and 20-24 years (4.09 GPa) in men, and at 25-29 years (209.24 mg/cm3), 25-29 years (3.98 mm), and 20-24 years (3.33 GPa) in women, respectively. The TBD fell significantly (p < 0.05) beginning at 55-59 years in both sexes, with a relatively rapid decrease in women. The CoTh showed a significant decrease beginning at 40-44 years in men and 50-54 years in women. The EMTb showed a significant decrease beginning at 40-44 years in men and 55-59 years in women. Conclusions: The LD-100 system is a useful bone densitometry device and the database of age-related changes in TBD, CoTh, and EMTb established in this study will provide fundamental data for future studies related to bone status. © 2010 International Osteoporosis Foundation and National Osteoporosis Foundation.


Mano I.,Doshisha University | Horii K.,Oyo Electrical Co. | Fujita F.,Doshisha University | Nagatani Y.,Kobe City College of Technology | And 2 more authors.
Japanese Journal of Applied Physics | Year: 2014

An ultrasonic system is good for the evaluation of children because its noninvasiveness. The ultrasonic bone measurement system LD-100 has been developed on the basis of the principle of the fast and slow wave phenomenon in the wrist bone. In the measurement of small bones such as those of children, there are some problems due to the influences of circumferential waves on the fast and slow waves. When the diameters of the focused transducers were small, the appearance of the circumferential wave around the cortical bone became late, and it could avoid one of the influences of the circumferential waves. © 2014 The Japan Society of Applied Physics.


Mano I.,Doshisha University | Horii K.,Oyo Electrical Co. | Matsukawa M.,Doshisha University | Otani T.,Doshisha University
Japanese Journal of Applied Physics | Year: 2013

We have tried in vivo imaging of the distal forearm bone using ultrasonic echo waves. The obtained ultrasonic echo images were compared with X-ray computed tomography (CT) images. In the case of vertical incidence of an ultrasonic wave to the cortical bone surface, not only the outer and inner boundaries of the near side of the cortical bone but also the inner and outer boundaries of the far side of the cortical bone were identified. The thicknesses of the cortical bone and cancellous bone calculated using the echo waves approximately agreed with those determined from X-ray CT images. © 2013 The Japan Society of Applied Physics.


Mano I.,Doshisha University | Horii K.,Oyo Electrical Co. | Matsukawa M.,Doshisha University | Otani T.,Doshisha University
Japanese Journal of Applied Physics | Year: 2015

Ultrasonic transmitted waves were obtained in an in vitro swine distal ulna specimen, which mimics a human distal radius, that consists of interconnected cortical bone and cancellous bone. The transmitted waveforms appeared similar to the fast waves, slow waves, and overlapping fast and slow waves measured in the specimen after removing the surface cortical bone (only cancellous bone). In addition, the circumferential waves in the cortical bone and water did not affect the fast and slow waves. This suggests that the fast-and-slow-wave phenomenon can be observed in an in vivo human distal radius. © 2015 The Japan Society of Applied Physics.

Loading Oyo Electrical Co collaborators
Loading Oyo Electrical Co collaborators