Assessment of bone synthetic activity in inflammatory lesions and syndesmophytes in patients with ankylosing spondylitis: the potential role of 18F-fluoride positron emission tomography-magnetic resonance imaging

• Published in: Clinical and experimental rheumatology Vol. 33; no. 1; pp. 90 - 97
• Main Authors: Lee, Seung-Geun, Kim, In-Joo, Kim, Keun-Young, Kim, Hee-Young, Park, Kyoung-June, Kim, Seong-Jang, Park, Eun-Kyoung, Jeon, Yun-Kyung, Yang, Byeong-Yun, Kim, Geun-Tae
• Format: Journal Article
• Language: English
• Published: Italy 01.01.2015
• Subjects: Adult; Case-Control Studies; Fluorodeoxyglucose F18; Humans; Linear Models; Magnetic Resonance Imaging; Male; Middle Aged; Multimodal Imaging; Osteoblasts - diagnostic imaging; Osteoblasts - pathology; Osteogenesis; Positron-Emission Tomography; Predictive Value of Tests; Prospective Studies; Radiopharmaceuticals; Spine - diagnostic imaging; Spine - pathology; Spondylitis, Ankylosing - diagnosis; Spondylitis, Ankylosing - diagnostic imaging; Spondylitis, Ankylosing - pathology
• ISSN: 0392-856X

18F-fluoride uptake represents active osteoblastic bone synthesis. We assessed bone synthetic activity in inflammatory lesions and syndesmophytes in patients with ankylosing spondylitis (AS) using 18F-fluoride positron emission tomography-magnetic resonance imaging (PET-MRI, Philips Healthcare, Cleveland, OH, USA) and x-ray. All images of 12 AS patients were recorded with the presence or absence of increased 18F-fluoride uptake lesions on PET, acute (type A) or advanced (type B) corner inflammatory lesions (CILs) on MRI, syndesmophytes on x-ray at the anterior vertebral corners. An increased 18F-fluoride uptake lesion was defined as an uptake which is greater than the uptake in the adjacent normal vertebral body. The association of a CIL or syndesmophyte with an increased 18F-fluoride uptake lesion was investigated by generalised linear latent mixed models analysis to adjust within-patient dependence for total numbers of vertebral corners. There were 67 type A CILs (12.1%), 37 type B CILs (6.7%) and 58 increased 18F-fluoride uptake lesion (10.4%) out of 552 vertebral corners and there were 57 syndesmophytes (19.8%) out of 288 vertebral corners. A type A CIL (OR=3.2, 95% CI=1.6-6.5, p=0.001), type B CIL (OR=59.9, 95% CI=23.5-151.5, p<0.001) and syndesmpophyte (OR=21.8, 95% CI=5.5-85.2, p<0.001) were significantly associated with an increased 18F-fluoride uptake lesion. Our data suggest that an inflammatory lesion as well as a syndesmophyte is associated with active bone synthesis assessed by 18F-fluoride uptake in the spine of AS patients. 18F-fluoride PET-MRI may have the potential for investigating the pathogenesis of structural damage in AS.