title: 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.
abstract: OBJECTIVE
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, South Korea.
authors.forename: Seung-Geun
authors.initials: SG
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, and Department of Nuclear Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, South Korea.
authors.forename: In-Joo
authors.initials: IJ
authors.lastname: Kim
authors.affiliation: Department of Nuclear Medicine, Kosin University College of Medicine, Busan, South Korea.
authors.forename: Keun-Young
authors.initials: KY
authors.lastname: Kim
authors.affiliation: Department of Nuclear Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, South Korea.
authors.forename: Hee-Young
authors.initials: HY
authors.lastname: Kim
authors.affiliation: Department of Nuclear Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, South Korea.
authors.forename: Kyoung-June
authors.initials: KJ
authors.lastname: Park
authors.affiliation: Department of Nuclear Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, South Korea.
authors.forename: Seong-Jang
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, South Korea.
authors.forename: Eun-Kyoung
authors.initials: EK
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, South Korea.
authors.forename: Yun-Kyung
authors.initials: YK
authors.lastname: Jeon
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, South Korea.
authors.forename: Byeong-Yun
authors.initials: BY
authors.lastname: Yang
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Kosin University College of Medicine, Busan, South Korea.
authors.forename: Geun-Tae
authors.initials: GT
authors.lastname: Kim
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D019788:Fluorodeoxyglucose F18; D006801:Humans; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D010006:Osteoblasts / Q000000981:diagnostic imaging / Q000473:pathology; D010012:Osteogenesis; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D013131:Spine / Q000000981:diagnostic imaging / Q000473:pathology; D013167:Spondylitis, Ankylosing / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18