Alves J M, Ryaby J T, Kaufman J J, Magee F P, Siffert R S
Department of Orthopaedics, MS 1188, The Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, New York 10029, USA.
Calcif Tissue Int. 1996 May;58(5):362-7. doi: 10.1007/BF02509386.
Measurements of ultrasonic velocity and specific differential attenuation (SDA) were obtained on 24 bovine trabecular bone specimens from the femoral condyles. The measurements were obtained using two pairs of ultrasonic transducers, one with a low nominal center frequency (500 kHz) and the other pair with a high nominal center frequency (1 MHz). The ultrasonic velocity and specific differential attenuation associated with the bone samples were determined both with and without marrow, i.e., replacing the marrow with water in the pores of the trabecular bone. Significant increases (2.1% and 2.9%) in the velocity of ultrasound were observed after removal of the marrow, for the low and high frequency transducer pairs, respectively. In contrast, significant decreases (-6.5% and -8.8%) in SDA were observed after removal of the marrow, for the low and high frequency transducer pairs, respectively. The bone densities (BD) of the samples were also determined using single photon absorptiometry (SPA). Correlations between ultrasonic parameters and bone densities for samples both with and without marrow were found to be similar. For example, for the 1 MHz transducer pair, the correlation between BD and velocity was r = 0. 86 with marrow, and r = 0.89 without marrow. This study also compared the results obtained using a contact (no water bath) technique and an insertion (with a water bath) technique of ultrasonic measurements. For the high frequency transducer pair, the correlation coefficients between the two methods were r = 0.99 and r = 0.93, for the velocity and specific differential attenuation, respectively. Similar results were found for the low frequency transducer pair as well. In addition, approximately equal correlations between BD and ultrasonic velocity and SDA were also found, indicating that contact and insertion measurements provide essentially equivalent information.
对取自股骨髁的24个牛松质骨标本进行了超声速度和比差分衰减（SDA）测量。测量是使用两对超声换能器进行的，一对具有低标称中心频率（500 kHz），另一对具有高标称中心频率（1 MHz）。分别在有骨髓和无骨髓的情况下（即用水替代松质骨孔隙中的骨髓）测定与骨样本相关的超声速度和比差分衰减。对于低频和高频换能器对，去除骨髓后分别观察到超声速度显著增加（2.1%和2.9%）。相比之下，对于低频和高频换能器对，去除骨髓后分别观察到SDA显著降低（-6.5%和-8.8%）。还使用单光子吸收法（SPA）测定了样本的骨密度（BD）。发现有骨髓和无骨髓样本的超声参数与骨密度之间的相关性相似。例如，对于1 MHz换能器对，有骨髓时BD与速度的相关性为r = 0.86，无骨髓时为r = 0.89。本研究还比较了使用接触（无水浴）技术和插入（有水浴）技术进行超声测量所获得的结果。对于高频换能器对，两种方法之间速度和比差分衰减的相关系数分别为r = 0.99和r = 0.93。低频换能器对也得到了类似结果。此外，还发现BD与超声速度和SDA之间的相关性大致相等，这表明接触式和插入式测量提供的信息基本等效。
