软组织硬度超声测试系统用于类风湿足底软组织评估

Abstract

测量软组织的硬度能够评估某些疾病的严重程度,但是临床上广泛使用的触摸诊断只能根据操作者的感觉定性地给出一个硬度的变化值,结果很大程度上受制于操作者的经验,所以有必要开发定量客观评估软组织硬度的工具。本文介绍一种软组织硬度超声测试系统,该系统以超声探头作为印压头,以超声信号获取被测组织的形变,利用印压实验测量软组织的力学特性。在引言部分我们回顾了该系统到目前为止在各种软组织测试当中的应用,正文部分我们主要报导此系统用于测量类风湿病人足底软组织硬度的变化。测试结果显示,有足部畸形的类风湿病人的第五跖骨头下软组织硬度为(67.1±38.1)kPa,明显高于正常人(46.0±12.1)kPa(p=0.021)。类风湿病人第一和第五跖骨头下面软组织厚度也明显小于正常人(p=0.010及p=0.027)。实验结果证明类风湿病人的足部畸形会导致外侧跖骨头下软组织硬度的增加。该超声硬度测试系统还可以用来监测类风湿病人脚底软组织力学特性随病变时间的变化。 Measurement of soft tissue stiffness can be used to assess the severity of some diseases.This is usually performed by hand palpation in clinics and the operators try to give a qualitative or at most semi-quantitative value of stiffness according to their feelings from the finger.The results are quite subjective and very depend on the experience of the operators.Therefore,it is necessary to develop some quantitative and objective tools to assess the stiffness of soft tissues.In this study,we introduce the tissue ultrasound palpation system (TUPS),which measures the soft tissue stiffness by utilizing the ultrasound transducer itself to indent the tissue and the ultrasound signal to extract the deformation of the tested tissue during indentation.The various applications of TUPS for soft tissue assessment that have been investigated up to date are reviewed in the introduction part.Then we report the application of this system to assess the mechanical properties of plantar soft tissues in patients with rheumatoid arthritis (RA).Results showed that stiffness of soft tissues at the fifth metatarsal head of the rheumatoid feet with deformity[(67.1±38.1) kPa] was significantly larger than that in normal subjects [(46.0±12.1kPa)](p=0.021).The thickness at the first and fifth metatarsal heads in rheumatoid feet was significantly smaller than that in normal subjects (p=0.010 and p=0.027,respectively).Our study showed that foot deformity in RA patients significantly increases the stiffness of plantar soft tissues in the lateral metatarsal region.The TUPS can also be used for a longitudinal follow-up of change of the plantar soft tissue stiffness as an indicator of the progression of rheumatoid feet.