title: Comparing diffusion weighted imaging with clinical and blood parameters, and with short tau inversion recovery sequence in detecting spinal and sacroiliac joint inflammation in axial spondyloarthritis.
abstract: OBJECTIVE
  To investigate the usefulness of diffusion weighted imaging (DWI) by comparing with clinical features, blood parameters and traditional short tau inversion recovery (STIR) sequence in detecting spinal and sacroiliac (SI) joint inflammation in axial spondyloarthritis (axSpA) patients.
  
  
  METHODS
  One hundred and ten axSpA patients were recruited. Clinical, radiological and blood parameters were recorded. DWI and STIR MRI were performed simultaneously and results were scored according to the Spondyloarthritis Research Consortium of Canada (SPARCC) for comparison. Apparent diffusion coef cient (ADC) values were also calculated.
  
  
  RESULTS
  DWI did not correlate with clinical parameters or blood parameters. It also had lowered sensitivity. When compared with STIR sequence, it correlated well with STIR sequence at the SI joint level (CC 0.76, p<0.001), but weakly at the spinal level (CC 0.23, p=0.02). At the SI joint level, the presence of inflammation on both STIR sequence and DWI was associated with an increase in maximum (B=0.24, p=0.02 in STIR; B=0.37, p<0.001 in DWI) and mean ADC values (B=0.17, p=0.003 in STIR; B=0.15, p=0.01 in DWI). Maximum (B=0.19, p=0.04) and mean spinal ADC values (B=0.18, p=0.01) were also positively associated with DWI detected spinal inflammation. Presence of Modic lesions showed positive correlation with STIR sequence (B=7.12, p=0.01) but not spinal ADC values.
  
  
  CONCLUSIONS
  Despite DWI correlates with STIR sequence, it has lower sensitivity. However, ADC values appear to be independent of Modic lesions and may supplement STIR sequence to differentiate degeneration.
authors.affiliation: Division of Rheumatology and Clinical Immunology, Queen Mary Hospital, Hong Kong, China.
authors.forename: Ho Yin
authors.initials: HY
authors.lastname: Chung
authors.affiliation: Department of Diagnostic Radiology, The University of Hong Kong, China.
authors.forename: Xiaopei
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Radiology, Queen Mary Hospital, Hong Kong, China.
authors.forename: Vince Wing Hang
authors.initials: VW
authors.lastname: Lau
authors.affiliation: Department of Radiology, Queen Mary Hospital, Hong Kong, China.
authors.forename: Grace
authors.initials: G
authors.lastname: Ho
authors.affiliation: Division of Rheumatology, Pamela Youde Nethersole Eastern Hospital, Hong Kong, China.
authors.forename: Ka Lai
authors.initials: KL
authors.lastname: Lee
authors.affiliation: Division of Rheumatology and Clinical Immunology, Queen Mary Hospital, Hong Kong, China.
authors.forename: Philip Hei
authors.initials: PH
authors.lastname: Li
authors.affiliation: Division of Rheumatology and Clinical Immunology, Queen Mary Hospital, Hong Kong, China.
authors.forename: Helen Hoi Lun
authors.initials: HH
authors.lastname: Tsang
authors.affiliation: Division of Rheumatology and Clinical Immunology, Queen Mary Hospital, Hong Kong, China.
authors.forename: Suet Kei
authors.initials: SK
authors.lastname: Kwok
authors.affiliation: Division of Rheumatology and Clinical Immunology, Queen Mary Hospital, Hong Kong, China.
authors.forename: Chak Sing
authors.initials: CS
authors.lastname: Lau
authors.affiliation: Department of Radiology, Baptist Hospital, Hong Kong, China. drcswong@gmail.com.
authors.forename: Chun Sing
authors.initials: CS
authors.lastname: Wong
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D001799:Blood Sedimentation; D003430:Cross-Sectional Studies; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006723:Hong Kong; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D012446:Sacroiliac Joint / Q000000981:diagnostic imaging*; D012720:Severity of Illness Index; D013131:Spine / Q000000981:diagnostic imaging*; D025241:Spondylarthritis / Q000097:blood / Q000000981:diagnostic imaging* / Q000503:physiopathology
chemical_list: D015415:Biomarkers