Veronika Zubler

Hip MRI: How Useful Is Intraarticular Contrast Material for Evaluating Surgically Proven Lesions of the Labrum and Articular Cartilage?

OBJECTIVE The objective of our study was to prospectively compare the diagnostic performance of MR arthrography and conventional MRI with surgical correlation in the same patient for detecting labrum and articular cartilage defects. SUBJECTS AND METHODS Twenty-eight patients (mean age, 31.8 years) underwent MR arthrography, conventional MRI, and subsequent hip surgery, which served as the reference standard. Labrum and cartilage defects were evaluated at MRI by two independent readers. A McNemar test and kappa statistics were used for statistical analysis. RESULTS At surgery, 31 labral tears were identified. MR arthrography had an advantage over conventional MRI for detecting labral tears at the anterosuperior quadrant (sensitivity of MR arthrography, 81% and 69% for readers 1 and 2, respectively; sensitivity of conventional MRI, 50% for both readers); this difference in performance between MR arthrography and conventional MRI was statistically significant for reader 1 (p = 0.02) but not for reader 2 (p = 0.2). Interobserver agreement for labral tears was higher for MR arthrography (κ = 0.81) than for conventional MRI (κ = 0.63). Surgery showed 31 acetabular cartilage defects and nine femoral cartilage defects. MR arthrography had an advantage over conventional MRI for detecting acetabular cartilage defects (sensitivity of MR arthrography, 71% and 92% for readers 1 and 2, respectively; sensitivity of conventional MRI, 58% and 83%), whereas there was no advantage to using MR arthrography for detecting femoral cartilage defects with statistically significant difference for the acetabular cartilage or femoral cartilage. Interobserver agreement was slightly higher for MR arthrography (κ = 0.50) than for conventional MRI (κ = 0.40) for assessing the acetabular cartilage and was almost identical for the femoral cartilage (κ = 0.62 and 0.63, respectively). CONCLUSION MR arthrography was superior to conventional MRI for detecting labral tears and acetabular cartilage defects and showed a higher interobserver agreement. For femoral cartilage lesions, both modalities yielded comparable results.

Does spinal MRI add incremental diagnostic value to MRI of the sacroiliac joints alone in patients with non-radiographic axial spondyloarthritis?

OBJECTIVE To assess the incremental diagnostic value of spine MRI evaluated separately from and combined with sacroiliac joint (SIJ) MRI in non-radiographic axial spondyloarthritis (nr-axSpA) compared with SIJ MRI alone. METHODS The study sample comprised two independent cohorts A/B of 130 consecutive patients aged ≤50 years with back pain, newly referred to two university clinics, and 20 healthy controls. Patients were classified according to clinical examination and pelvic radiographs as having nr-axSpA (n=50), ankylosing spondylitis (n=33), or non-specific back pain (n=47). Four readers assessed SIJ and spine MRI separately 6 months apart, and 1-12 months later both scans simultaneously using standardised modules. Readers recorded presence/absence of SpA and their level of confidence in this conclusion on a 0-10 scale (0=definitely not; 10=definite). We analysed differences between SIJ MRI versus spine MRI alone, and SIJ MRI alone versus combined MRI, descriptively by the number/percentage of subjects according to the mean of four readers. RESULTS In cohorts A/B, 15.8%/24.2% of patients with nr-axSpA having a negative SIJ MRI were reclassified as being positive for SpA by global evaluation of combined scans. However, 26.8%/11.4% of non-specific back pain controls and 17.5% of healthy volunteers with a negative SIJ MRI were falsely reclassified as having SpA by combined MRI. Low confidence in a diagnosis of SpA by SIJ MRI increased to high confidence by combined MRI in 6.6%/7.3% of patients with nr-axSpA. CONCLUSIONS Combined spine and SIJ MRI added little incremental value compared with SIJ MRI alone for diagnosing patients with nr-axSpA and enhancing confidence in this diagnosis.

Development and Validation of a Magnetic Resonance Imaging Reference Criterion for Defining a Positive Sacroiliac Joint Magnetic Resonance Imaging Finding in Spondyloarthritis

To validate a magnetic resonance imaging (MRI) reference criterion for a positive sacroiliac (SI) joint MRI finding based on the level of confidence in the classification of spondyloarthritis (SpA) by expert MRI readers.

Candidate lesion-based criteria for defining a positive sacroiliac joint MRI in two cohorts of patients with axial spondyloarthritis

Objective To determine candidate lesion-based criteria for a positive sacroiliac joint (SIJ) MRI based on bone marrow oedema (BMO) and/or erosion in non-radiographic axial spondyloarthritis (nr-axSpA); to compare the performance of lesion-based criteria with global evaluation by expert readers. Methods Two independent cohorts A/B of 69/88 consecutive patients with back pain aged ≤50 years, with median symptom duration 1.3/10.0 years, were referred for suspected SpA (A) or acute anterior uveitis plus back pain (B). Patients were classified according to rheumatologist expert opinion based on clinical examination, pelvic radiography and laboratory values as having nr-axSpA (n=51), ankylosing spondylitis (n=34) or non-specific back pain (n=72). Four blinded readers assessed SIJ MRI, recording the presence/absence of SpA by concomitant global evaluation of T1-weighted spin echo (T1SE) and short τ inversion recovery (STIR) scans and, thereafter, whether BMO and/or erosion were present/absent in each SIJ quadrant of each MRI slice. We derived candidate lesion-based criteria based on the number of SIJ quadrants with BMO and/or erosion and calculated mean sensitivity and specificity for SpA. Results For both cohorts A/B, global assessment showed high specificity (0.95/0.83) compared with the Assessment in SpondyloArthritis international Society (ASAS) definition (0.76/0.74). BMO ≥3 (0.89/0.84) or ≥4 (0.92/0.87) showed comparably high specificity to global assessment. Erosion ≥2 and/or BMO ≥3 or ≥4 were associated with comparably high sensitivity to global assessment without affecting specificity. These combined criteria showed both higher sensitivity and specificity than the ASAS definition. Conclusions Lesion-based criteria for a positive SIJ MRI based on both BMO and/or erosion performed best for classification of axial SpA, reflecting the contextual information provided by T1SE and STIR sequences.

Diagnostic utility of candidate definitions for demonstrating axial spondyloarthritis on magnetic resonance imaging of the spine.

A recent consensus statement has suggested ≥3 corner inflammatory lesions (CILs) or several corner fatty lesions (CFLs) as candidate criteria indicative of axial spondyloarthritis (SpA) on magnetic resonance imaging (MRI) of the spine. The aim of this study was to evaluate the diagnostic utility of these cutoffs in nonradiographic axial SpA and ankylosing spondylitis (AS).

High bone turnover assessed by 18F-fluoride PET/CT in the spine and sacroiliac joints of patients with ankylosing spondylitis: comparison with inflammatory lesions detected by whole body MRI.

BackgroundThis study compares the frequency and distribution of increased activity on 18 F-fluoride PET/CT with the presence of bone marrow edema on whole-body MR imaging in the spine and sacroiliac joints (SIJ) of patients with active ankylosing spondylitis (AS).MethodsTen patients (6 men and 4 women), between 30 and 58 years old (median 44) with active AS, were prospectively examined with both whole-body MRI and 18 F-fluoride PET/CT. Patients fulfilled modified NY criteria and had a Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) of at least 4. Increased radiotracer uptake in PET/CT and bone marrow edema in whole-body MRI of spine and SIJ was evaluated independently by two blinded observers for each modality. Kappa statistics were used to compare interobserver agreement as well as scores of consensus reading of the two imaging modalities.ResultsAnalysis of interobserver agreement for PET/CT yielded a kappa value of 0.68 for spinal lesions and of 0.88 for SIJ lesions. The corresponding kappa values for the MRI modality were 0.64 and 0.93, respectively. More spinal lesions were detected by MRI in comparison to PET/CT (68 vs. 38), whereas a similar number of SIJ quadrants scored positive in both modalities (19 vs. 17). Analysis of agreement of lesion detection between both imaging modalities yielded a kappa value of only 0.25 for spinal lesions and of 0.64 for SIJ lesions.ConclusionIncreased 18 F-fluoride uptake in PET/CT is only modestly associated with bone marrow edema on MRI in the spine and SIJ of patients with AS, suggesting different aspects of bone involvement in AS.

Elbow stiffness: effectiveness of conventional radiography and CT to explain osseous causes.

OBJECTIVE The purpose of our study was to evaluate the effectiveness of conventional radiography and CT for explaining the osseous causes of elbow stiffness. MATERIALS AND METHODS Two independent readers analyzed loose bodies and osteophytes on conventional radiography and CT (or CT arthrography) of the elbow in 94 consecutive patients (71 men, 23 women; mean age, 41 years; range, 18-68 years). Arthroscopic or surgical correlation was available in 58 (62%) patients. In all 94 patients, the expected restriction of motion was measured on images and correlated (Pearsons correlation) with the clinical restriction of motion. Kappa statistics were performed for interobserver agreement. RESULTS Accuracy for detecting loose bodies was 67% with conventional radiography and 79% with CT. Differences in accuracy were most pronounced for detecting loose bodies in the posterior joint space (64% for conventional radiography vs 79% for CT). Accuracy for detecting osteophytes was 69% with conventional radiography and 76% with CT. Expected restriction of motion on conventional radiography correlated significantly with clinical restriction for only one reader for flexion (R = 0.21, p = 0.04). Expected restriction of extension on CT correlated significantly with clinical restriction of motion by both readers (R = 0.34 and 0.33, p = 0.001 and 0.001, respectively). Expected restriction of flexion on CT correlated significantly by one reader (R = 0.24, p = 0.02). Interobserver agreement with regard to detection of both loose bodies and osteophytes was higher for CT (kappa = 0.83 and 0.76) than for conventional radiography (0.64 and 0.60). CONCLUSION CT is more effective than conventional radiography in explaining the osseous causes of elbow stiffness.

Methodologies for Semiquantitative Evaluation of Hip Osteoarthritis by Magnetic Resonance Imaging: Approaches Based on the Whole Organ and Focused on Active Lesions

Objective. As a wider variety of therapeutic options for osteoarthritis (OA) becomes available, there is an increasing need to objectively evaluate disease severity on magnetic resonance imaging (MRI). This is more technically challenging at the hip than at the knee, and as a result, few systematic scoring systems exist. The OMERACT (Outcome Measures in Rheumatology) filter of truth, discrimination, and feasibility can be used to validate image-based scoring systems. Our objective was (1) to review the imaging features relevant to the assessment of severity and progression of hip OA; and (2) to review currently used methods to grade these features in existing hip OA scoring systems. Methods. A systematic literature review was conducted. MEDLINE keyword search was performed for features of arthropathy (such as hip + bone marrow edema or lesion, synovitis, cyst, effusion, cartilage, etc.) and scoring system (hip + OA + MRI + score or grade), with a secondary manual search for additional references in the retrieved publications. Results. Findings relevant to the severity of hip OA include imaging markers associated with inflammation (bone marrow lesion, synovitis, effusion), structural damage (cartilage loss, osteophytes, subchondral cysts, labral tears), and predisposing geometric factors (hip dysplasia, femoral-acetabular impingement). Two approaches to the semiquantitative assessment of hip OA are represented by Hip OA MRI Scoring System (HOAMS), a comprehensive whole organ assessment of nearly all findings, and the Hip Inflammation MRI Scoring System (HIMRISS), which selectively scores only active lesions (bone marrow lesion, synovitis/effusion). Validation is presently confined to limited assessment of reliability. Conclusion. Two methods for semiquantitative assessment of hip OA on MRI have been described and validation according to the OMERACT Filter is limited to evaluation of reliability.

Dynamic Imaging and Function of Partial Supraspinatus Tendon Tears

PURPOSE It was the purpose of this study to identify and document normal and abnormal supraspinatus tendon function in vivo using real-time ultrasound. METHODS We defined 4 groups of 20 individuals each: partial tear (group 1), full-thickness tear (group 2), successfully repaired tear (group 3), and healthy asymptomatic controls (group 4). Except for group 4, all patients underwent magnetic resonance arthrography to confirm the diagnosis. All underwent ultrasound imaging of the supraspinatus tendon with the adducted arm at rest and under maximal isometric abduction. Tendon deformation was dynamically assessed and measured with tendon thickness changes at 0.5, 1, 1.5, and 2 cm from the tendon insertion. The clinical assessment consisted of absolute and relative Constant score, subjective shoulder value, and strength measurements. RESULTS Without muscle contraction, the tendons of the 4 groups were not of significantly different thickness, with the least variation at 1.5 cm from the insertion site. On contraction, the normal tendon thickness significantly increased at a distance of 2 cm, whereas it did not for the full-thickness and partial supraspinatus tears. Thus contraction of the muscle resulted in measurable deformation of the tendon. CONCLUSIONS Partially torn supraspinatus tendons can be functionally incompetent, leading to a biomechanical deformation of the musculotendinous unit that is not different from that of a unit with a full-thickness tendon tear. The dynamic sonographic finding of a successful repair of a supraspinatus tendon is similar to that of a normal tendon, even though the previously injured muscle appears unable to generate the same strength as a normal muscle. LEVEL OF EVIDENCE Level III, case-control study.

FRI0147 Data Driven Lesion-Based Criteria for Defining A Positive Sacroiliac Joint MRI in 2 Cohorts with Axial Spondyloarthritis

Background The ASAS definition of a positive sacroiliac joint (SIJ) MRI for axial spondyloarthritis (SpA) is based exclusively on bone marrow edema (BME). The contextual information of concomitant BME and/or erosion on T1SE and STIR sequences led to the MORPHO definition, which improved sensitivity without worsening specificity compared to the ASAS definition in a non-radiographic axial SpA (nr-axSpA) cohort of short symptom duration. Objectives To compare MORPHO and ASAS definitions for a positive SIJ MRI with global assessment by expert readers in patients with a broad spectrum of nr-axial SpA. To determine optimal lesion-based definitions for a positive SIJ MRI based on BME and/or erosion. Methods The sample comprised 2 independent cohorts A/B of 69/88 consecutive back pain patients ≤50 years, median symptom duration 1.3/10.0 years, newly referred to 2 university clinics for suspected SpA (A) or acute anterior uveitis (AAU) and back pain (B), and 20 healthy controls. Patients were classified according to rheumatologist expert opinion based on clinical examination, pelvic radiography and laboratory values as having nr-axSpA (n=51), AS (n=34), or MBP (n=72). SIJ MRI were assessed independently by 4 blinded readers according to standardized modules in which readers first recorded presence/absence of SpA by global evaluation of T1SE and STIR sequences, and subsequently reported whether BME or erosion were present for each SIJ quadrant on all MRI slices. We calculated sensitivity and specificity as mean values over 4 readers for global assessment, ASAS and MORPHO definitions. We derived candidate definitions based on the number of SIJ quadrants with BME and/or erosion to determine which might be optimal in both cohorts. Results For both cohorts, global assessment and “≥2 SIJ quadrants with erosion” showed the highest specificity. The MORPHO definition had increased sensitivity compared to the ASAS definition, with a slight drop in specificity. “BME in ≥3 SIJ quadrants” improved specificity over ASAS or MORPHO definitions although the combined criterion “≥3 BME and/or ≥2 erosions” showed both a higher sensitivity and specificity. Table 1. Sensitivity and specificity of candidate criteria for a positive SIJ MRI in SpA (mean over 4 readers): nr-axSpA versus MBP Cohort A: Back pain suspicious for SpA B: AAU plus back pain Sensitivity Specificity Sensitivity Specificity Global assessment 73.8 94.9 43.5 82.6 ASAS definition 80.0 75.6 41.9 73.5 MORPHO definition 87.5 72.4 54.0 72.0 ER ≥2 57.5 96.8 29.8 90.2 BME ≥2 80.0 76.3 41.9 72.7 BME ≥2 and/or ER ≥1 87.5 72.4 54.8 69.7 BME ≥2 and/or ER ≥2 87.5 73.1 53.2 71.2 BME ≥3 75.0 88.5 33.9 84.1 BME ≥3 and/or ER ≥1 82.5 84.6 47.6 78.8 BME ≥3 and/or ER ≥2 82.5 85.3 46.0 81.8 Conclusions A stringent lesion-based definition of a positive SIJ MRI, based on both BME and erosion, performed best for classification of axial SpA. Disclosure of Interest None declared DOI 10.1136/annrheumdis-2014-eular.3413