Inflammatory and structural evaluation in spondyloarthritis: magnetic resonance imaging analysis of axial and peripheral involvement.
OBJECTIVE
To determine the magnetic resonance imaging (MRI) criteria of most value in the assessment of patients with spondyloarthropathy (SpA) with axial or peripheral involvement.


METHODS
Fat suppressed (FS)-T2 and pre- and postinjection FS-T1 images were obtained in the most symptomatic region (axial or peripheral) of patients requiring tumor necrosis factor-a blockers. Thirty-eight MRI (21 axial and 17 peripheral) were blindly scored at synovial (S) and entheseal (E) sites by 2 experienced observers screening for 7 inflammatory and 7 structural predefined criteria, which were evaluated for frequency (N) and intra- and interobserver reproducibility.


RESULTS
In peripheral regions, synovitis (S; N = 69.4%), ligament inflammation (E; N = 39.7%), bone marrow edema (S; N = 22.1%; E; N = 15%), and tenosynovitis (S; N = 21%) were recorded with good to excellent intraobserver reproducibility [intraclass correlation coefficient (ICC) 0.49-0.93] and moderate to good interobserver reproducibility (ICC 0.49-0.66). With regard to structural criteria, erosions (S; N = 17.1%) and enthesophytes (E; N = 13.9%) exhibited good to excellent intraobserver (ICC 0.71-0.85) and moderate interobserver reproducibility (ICC 0.54-0.49); the reproducibility of fat inflation (N = 1.4%) was good (ICC 0.76-0.78). In axial regions, no inflammatory criteria achieved good interobserver reproducibility. However, fat inflation (S; N = 86%), chondral lesions (S; N = 85.8%), enthesophytes (E; N = 76.7%), fusion (S; N = 41.2%), and erosions (S; N = 25.1%) showed excellent intraobserver reproducibility (ICC 0.81-0.98), and moderate to excellent interobserver reproducibility (ICC 0.50-0.96).


CONCLUSIONS
In terms of intra- and interobserver reproducibility, MRI is a reliable tool with which to assess synovitis, bone edema, ligament inflammation, tenosynovitis, erosion, enthesophytes, and fat inflation in patients with peripheral involvement. In those with axial involvement, inflammatory criteria lack interobserver reproducibility, but chondral lesions, erosion, fat inflation, fusion, and enthesophytes are relevant.
Hoenen-Clavert
Virginie
V
Department of Rheumatology, Hôpitaux de Brabois, Vandoeuvre, France.
Rat
Anne Christine
AC
Loeuille
Damien
D
Bettembourg-Brault
Isabelle
I
Michel-Batot
Christine
C
Blum
Alain
A
Pourel
Jacques
J
Chary-Valckenaere
Isabelle
I
D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007596:Joints / Q000473:pathology*; D008022:Ligaments / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015588:Observer Variation; D010000:Osteitis / Q000175:diagnosis / Q000473:pathology*; D010147:Pain Measurement; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D016037:Single-Blind Method; D025242:Spondylarthropathies / Q000175:diagnosis / Q000473:pathology*; D013585:Synovitis / Q000473:pathology; D013717:Tenosynovitis / Q000473:pathology