Reginster J Y, Dethor M, Pirenne H, Dewe W, Albert A
CHU Centre Ville, Department of Public Health and Epidemiology, University of Liège, Belgium.
Int J Gynaecol Obstet. 1998 Oct;63(1):21-8. doi: 10.1016/s0020-7292(98)00113-1.
The present study was designed to assess the reproducibility and the diagnostic sensitivity of the amplitude-dependent speed of sound (SoS) at the distal metaphysis of the proximal phalanges.
Fourteen presumably healthy volunteers were repeatedly measured every 6 weeks for approximately 6 months in order to assess the reproducibility of the SoS of the phalanges. We recruited 91 post-menopausal women, aged 55-75 years, who were divided in three groups according to their lumbar bone mineral density (BMD) and the existence of prevalent vertebral fractures. The objective was to evaluate the diagnostic sensitivity of SoS measurements. We used DBM Sonic 1200 equipment, and assessed the velocity at which US cross the phalanx in a lateral-medial direction. In post-menopausal women, BMD was measured by dual energy X-ray absorptiometry (DXA) at the level of the lumbar spine, the total zone of the non-dominant hip and the femoral neck zone of the non-dominant hip.
The precision of the SoS measurements was 0.71+/-0.05% (mean+/-S.E.M) whereas the reproducibility was 0.95+/-0.06%. Subjects with low BMD or prevalent fractures had significantly lower values of SoS (P < 0.001) than the controls. ROC curve analysis applied to the study population confirmed that SoS was able to discriminate between the controls and osteoporotic subjects (area under the ROC curves were 0.82 (low bone mineral density) and 0.85 (prevalent fractures), respectively). Hip BMD was found to be the most significant variable when comparing the controls and the low density patients by stepwise discrimination and SoS significantly improved the discrimination between the groups when added to the hip BMD. The hip BMD was again the most discriminant variable when applying the same techniques to controls and patients with prevalent fractures, followed by SoS and lumbar BMD. A cut-off value of 1881 m/s is defined for SoS by logistic discrimination and likelihood ratio function. With this value, the sensitivity and the specificity for SoS used in the diagnosis of established osteoporosis were, 81.5% and 79.3%, respectively. Sensitivity and specificity were significantly improved when combining ultrasonometry and densitometry.
Measurement of ultrasound velocity at the phalanges appears to be a precise and reproducible technique. SoS discriminates between normal post-menopausal women and patients with either low lumbar BMD or prevalent fractures to the same extent as BMD measurements.
本研究旨在评估近节指骨远端干骺端处声速（SoS）的重现性及诊断敏感性。
14名健康志愿者每隔6周重复测量约6个月，以评估指骨SoS的重现性。我们招募了91名年龄在55 - 75岁之间的绝经后女性，根据她们的腰椎骨密度（BMD）及是否存在椎体骨折史将其分为三组。目的是评估SoS测量的诊断敏感性。我们使用DBM Sonic 1200设备，评估超声在内外侧方向穿过指骨的速度。在绝经后女性中，通过双能X线吸收法（DXA）测量腰椎、非优势侧全髋及非优势侧股骨颈区域的骨密度。
SoS测量的精密度为0.71±0.05%（均值±标准误），而重现性为0.95±0.06%。骨密度低或有骨折史的受试者SoS值显著低于对照组（P < 0.001）。对研究人群进行ROC曲线分析证实，SoS能够区分对照组和骨质疏松患者（ROC曲线下面积分别为0.82（低骨密度）和0.85（有骨折史））。通过逐步判别法比较对照组和低密度患者时，发现髋部骨密度是最显著的变量，当将SoS加入髋部骨密度时，SoS显著提高了组间判别能力。对对照组和有骨折史患者应用相同技术时，髋部骨密度仍是最具判别力的变量，其次是SoS和腰椎骨密度。通过逻辑判别和似然比函数确定SoS的截断值为1881 m/s。以此值用于诊断已确诊的骨质疏松时，SoS的敏感性和特异性分别为81.5%和79.3%。超声检查和骨密度测量联合使用时，敏感性和特异性显著提高。
指骨超声速度测量似乎是一种精确且可重复的技术。SoS在区分正常绝经后女性与腰椎骨密度低或有骨折史的患者方面，与骨密度测量具有相同的程度。
