title: Feasibility of US-CT image fusion to identify the sources of abnormal vascularization in posterior sacroiliac joints of ankylosing spondylitis patients.
abstract: Ultrasound (US) can be used to evaluate the inflammatory activity of the sacroiliac joints (SIJs) in ankylosing spondylitis (AS) patients, but to precisely locate the abnormal vascularization observed on color Doppler US (CDUS) was difficult. To address this issue, we performed US and computed tomography (CT) fusion imaging of SIJs with 84 inpatients and 30 controls, and then assessed the sources of abnormal vascularization in the posterior SIJs of AS patients based on the fused images. Several possible factors impacting the fusion process were considered including the lesion classes of SIJ, the skinfold thickness of the sacral region and the cross-sectional levels of the first, second and third posterior sacral foramina. Our data showed high image fusion success rates at the 3 levels in the AS group (97.0%, 87.5% and 79.8%, respectively) and the control group (96.7%, 86.7%, and 86.7%, respectively).The skinfold thickness was identified as the main factor affecting the success rates. The successfully fused images revealed significant differences in the distribution of abnormal vascularization between 3 levels, as detected via CDUS (P = 0.011), which suggested that inflammation occurred in distinct tissues at different levels of the SIJ (intraligamentous inflammation in Regions 1 and 2; intracapsular inflammation in Region 3).
authors.affiliation: Department of Ultrasound, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, No. 600 Yishan Road, Shanghai, 200233, People's Republic of China.|Shanghai Institute of Ultrasound in Medicine, No. 600 Yishan Road, Shanghai, 200233, People's Republic of China.
authors.forename: Zhenlong
authors.initials: Z
authors.lastname: Hu
authors.affiliation: Department of Ultrasound, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, No. 600 Yishan Road, Shanghai, 200233, People's Republic of China.|Department of Ultrasound, Peking University People's Hospital, No. 11 Xizhimen South Street, Beijing, 100044, People's Republic of China.
authors.forename: Jiaan
authors.initials: J
authors.lastname: Zhu
authors.affiliation: Department of Ultrasound, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, No. 600 Yishan Road, Shanghai, 200233, People's Republic of China.|Shanghai Institute of Ultrasound in Medicine, No. 600 Yishan Road, Shanghai, 200233, People's Republic of China.
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.affiliation: Department of Rheumatology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, No. 600 Yishan Road, Shanghai, 200233, People's Republic of China.
authors.forename: Niansong
authors.initials: N
authors.lastname: Wang
authors.affiliation: Department of Rheumatology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, No. 600 Yishan Road, Shanghai, 200233, People's Republic of China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Xue
mesh_terms: D000293:Adolescent; D000328:Adult; D018618:Echocardiography, Doppler, Color / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging*; D012446:Sacroiliac Joint / Q000000981:diagnostic imaging*; D013167:Spondylitis, Ankylosing / Q000000981:diagnostic imaging*