||Due to the prevalence of sports, there is bound to be a risk of sports injuries. Most human tissues damaged by sports injuries are tendons and muscles. If the relationship between muscles, tendons and tension can be known, providing data for medical diagnosis can be more convenient to make accurate judgments. This demand induces scientists to be curious about the relationship between human tissue and tension. Therefore, many methods for measuring human biological tissue have been established, which has enabled biomechanics to flourish. Although more and more attention has been paid to in vivo measurement in recent years, it is not easy to obtain real-time information through traditional measurement methods. Therefore, in order to solve this limitation, more measurement methods combined with imaging systems have been proposed and applied.|
Compared with traditional tension measurement methods, the photoacoustic imaging system can obtain real-time information of muscle and tendon tissue more quickly. In this experiment, a 1064 nm laser was used as the excitation light source for the photoacoustic signal to scan the two-dimensional photoacoustic signal. First, an electric translation stage was used to apply different tensions to the muscle and tendon tissue to observe the changes in the photoacoustic signal of the muscle and tendon tissue. However, the translation stage can only indicate the elongation when the tension is applied to the sample. In order to find the relationship between the tension and the elongation, this study uses springs to measure the samples separately and obtains the different elongations under the condition of known spring coefficients. Finally, we use the spring measurement result to compare the relationship between the photoacoustic signal change and the tension.
From the changes in the two-dimensional photoacoustic signal, it can be found that when the translation stage continues to stretch the sample, the photoacoustic signal will gradually decrease, and the signal decline after muscle and tendon stretching is not the same. In order to understand the relationship between tension and elongation, we used springs to do multiple measurements. It can be observed that the relationship between tension and elongation presented by the muscle and tendon samples are different. After measuring the experimental results of the spring, we can know the relationship between the photoacoustic signal and tension. We also do curve fitting of the photoacoustic signal, and we can find that the tendon samples are more consistent with the observations in the past literature However, the muscle sample does not meet the trend, and it is speculated here that there may be a difference in sample preparation. Based on the relationship between tension and photoacoustic signals obtained in this study, it will be possible to obtain real-time muscle and tendon tension information through the observation of photoacoustic images in the future.
|| R. Messier, J. a. Duffy, H. Litchman, P. Paslay, J. Soechting, and P. J. I. J. o. M. S. Stewart, |
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