Estimation of bone quality on scoliotic subjects using ultrasound reflection imaging method - a preliminary study

摘要

Osteopenia is indicated as a common phenomenon in patients who have scoliosis. Adolescent Idiopathic Scoliosis (AIS) is the most common form of scoliosis and defined as a three-dimensional spinal deformity. Quantitative ultrasound (QUS) has been used to assess skeletal status, and recently ultrasound imaging using reflection signals approach has been applied to measure the spinal curvature and vertebral rotation in children with AIS. The objectives of this study were to develop a new method to extract a parameter from the ultrasound spinal data to determine if bone quality can be estimated and differentiated with curve severity. Eighteen patients with AIS were divided into two groups (9/9) based on their curvature severities. The reflection index (RI) is the extracted parameter which is used to assess the bone quality at the tissue-cortical bone interface. It was calculated based on the original radio frequency (RF) ultrasound data using the following three amplitudes: peak amplitude, envelope amplitude and spectral amplitude. The RI calculated by the spectral amplitude using the least square (LS) method reported a more reliable and consistent results. The RI of the non-mild curve and mild curve groups were 0.47 and 0.74, respectively. The lower RI means the lower bone quality. This preliminary result reported that it might be feasible in using ultrasound imaging method to assess bone quality on patients who have AIS.