K.-G. Hermann

The Assessment of SpondyloArthritis international Society (ASAS) handbook: a guide to assess spondyloarthritis

The field of spondyloarthritis (SpA) has experienced major progress in the last decade, especially with regard to new treatments, earlier diagnosis, imaging technology and a better definition of outcome parameters for clinical trials. In the present work, the Assessment in SpondyloArthritis international Society (ASAS) provides a comprehensive handbook on the most relevant aspects for the assessments of spondyloarthritis, covering classification criteria, MRI and x rays for sacroiliac joints and the spine, a complete set of all measurements relevant for clinical trials and international recommendations for the management of SpA. The handbook focuses at this time on axial SpA, with ankylosing spondylitis (AS) being the prototype disease, for which recent progress has been faster than in peripheral SpA. The target audience includes rheumatologists, trial methodologists and any doctor and/or medical student interested in SpA. The focus of this handbook is on practicality, with many examples of MRI and x ray images, which will help to standardise not only patient care but also the design of clinical studies.

Defining active sacroiliitis on Magnetic Resonance Imaging (MRI) for classification of axial spondyloarthritis –a consensual approach by the ASAS/ OMERACT MRI Group

Background: Magnetic resonance imaging (MRI) of sacroiliac joints has evolved as the most relevant imaging modality for diagnosis and classification of early axial spondyloarthritis (SpA) including early ankylosing spondylitis. Objectives: To identify and describe MRI findings in sacroiliitis and to reach consensus on which MRI findings are essential for the definition of sacroiliitis. Methods: Ten doctors (two radiologists and eight rheumatologists) from the ASAS/OMERACT MRI working group reviewed and discussed in three workshops MR images depicting sacroiliitis associated with SpA and other conditions which may mimic SpA. Descriptions of the pathological findings and technical requirements for the appropriate acquisition were formulated. In a consensual approach MRI findings considered to be essential for sacroiliitis were defined. Results: Active inflammatory lesions such as bone marrow oedema (BMO)/osteitis, synovitis, enthesitis and capsulitis associated with SpA can be detected by MRI. Among these, the clear presence of BMO/osteitis was considered essential for defining active sacroiliitis. Structural damage lesions such as sclerosis, erosions, fat deposition and ankylosis can also be detected by MRI. At present, however, the exact place of structural damage lesions for diagnosis and classification is less clear, particularly if these findings are minor. The ASAS group formally approved these proposals by voting at the annual assembly. Conclusions: For the first time, MRI findings relevant for sacroiliitis have been defined by consensus by a group of rheumatologists and radiologists. These definitions should help in applying correctly the imaging feature “active sacroiliitis by MRI” in the new ASAS classification criteria for axial SpA.

Effects of etanercept versus sulfasalazine in early axial spondyloarthritis on active inflammatory lesions as detected by whole-body MRI (ESTHER): a 48-week randomised controlled trial

Purpose To evaluate the potential of etanercept versus sulfasalazine to reduce active inflammatory lesions on whole-body MRI in active axial spondyloarthritis with a symptom duration of less than 5 years. Methods Patients were randomly assigned to etanercept (n=40) or sulfasalazine (n=36) treatment over 48 weeks. All patients showed active inflammatory lesions (bone marrow oedema) on MRI in either the sacroiliac joints or the spine. MRI was performed at weeks 0, 24 and 48 and was scored for active inflammatory lesions in sacroiliac joints and the spine including posterior segments and peripheral enthesitis by two radiologists, blinded for treatment arm and MRI time point. Results In the etanercept group, the reduction of the sacroiliac joint score from 7.7 at baseline to 2.0 at week 48 was significantly (p=0.02) larger compared with the sulfasalazine group from 5.4 at baseline to 3.5 at week 48. A similar difference in the reduction of inflammation was found in the spine from 2.2 to 1.0 in the etanercept group versus from 1.4 to 1.3 in the sulfasalazine group between baseline and week 48, respectively (p=0.01). The number of enthesitic sites also improved significantly from 26 to 11 in the etanercept group versus 24 to 26 in the sulfasalazine group (p=0.04 for difference). 50% of patients reached clinical remission in the etanercept group versus 19% in the sulfasalazine group at week 48. Conclusion In patients with early axial spondyloarthritis active inflammatory lesions detected by whole-body MRI improved significantly more in etanercept versus sulfasalazine-treated patients. This effect correlated with a good clinical response in the etanercept group.

Inflammation in ankylosing spondylitis: a systematic description of the extent and frequency of acute spinal changes using magnetic resonance imaging

Background: Magnetic resonance imaging (MRI) is increasingly used to detect inflammation in the spine of patients with ankylosing spondylitis (AS). Objectives: To detect differentially the presence and extent of inflammation in the three spinal segments of patients with AS by MRI. Methods: In 38 patients with active AS, acute spinal lesions were assessed by T1 weighted, gadolinium enhanced, spin echo MRI (T1/Gd-DTPA) and short τ inversion recovery (STIR) sequences. MRI was quantified by the validated scoring system ASspiMRI-a. Acute spinal lesions were detected in the whole spine and in each spinal segment. One vertebral unit (VU) was defined as the region between two virtual lines drawn through the middle of each vertebral body. Results: A greater number of inflammatory spinal lesions were found by the STIR sequence than by Gd-DTPA: inflammation was present in 30.6% of the VUs as assessed by STIR, compared with 26.8% of the same VUs assessed by T1/Gd-DTPA. Inflammation was found more commonly in the thoracic spine (TS) than in the cervical (CS) or the lumbar spine (LS) with both techniques. When STIR was used, spinal inflammation in the CS, the TS, and LS was detected in 10/38 (26%), 28/38 (74%), and 9/38 (24%) patients, respectively. The VU T7/8 was found to be the VU most often affected by both techniques (27.8% by T1/Gd-DTPA and 34.5% by STIR). Conclusions: Spinal inflammation is a common manifestation in patients with AS, and appears more frequently in the TS. The scoring system ASspiMRI-a can be used for evaluation of acute spinal changes in AS.

Assessment of acute spinal inflammation in patients with ankylosing spondylitis by magnetic resonance imaging: a comparison between contrast enhanced T1 and short tau inversion recovery (STIR) sequences

Objectives: To compare the performance of two different MRI sequences—T1 weighted, fat saturated, spin echo after application of contrast medium, and short τ inversion recovery (STIR) sequences—to detect spinal inflammation in patients with ankylosing spondylitis (AS). Methods: Both MRI sequences were performed in 38 patients with active AS and compared using the MRI activity scoring system, ASspiMRI-a. One vertebral unit (VU) was defined as the region between two virtual lines drawn through the middle of each vertebral body. Results: Intraclass correlation coefficients were excellent—0.91 and 0.86 for the Gd-DTPA and STIR sequences, respectively. The overall correlation of the single MRI scores for both sequences was also good (r = 0.84, p = 0.01). The intrarater variance was 6.71 and 9.41 and the interrater variance was 13.16 and 19.04 for the Gd-DTPA and STIR sequences, respectively. The smallest detectable distance was 4.7 and 5.6 for the Gd-DTPA and STIR sequences, respectively. The concordance rate for both sequences was 83.5% (range 80.5–87.7% in the three spinal segments). Inflammatory spinal lesions were found in 10.1% of the VUs in the STIR sequence but not in the T1/Gd-DTPA sequence, while the T1/Gd-DTPA sequence showed inflammatory lesions in 6.4% of the VUs that were found normal by STIR. Conclusions: Both MRI techniques can evaluate active spinal lesions in patients with AS. More spinal lesions are detected by the STIR sequence, but the reliability between readings and readers is better for the Gd-DTPA sequence. The ASspiMRI-a is a reliable instrument for evaluating acute spinal changes in AS.

Relationship between active inflammatory lesions in the spine and sacroiliac joints and new development of chronic lesions on whole-body MRI in early axial spondyloarthritis: results of the ESTHER trial at week 48

Aim To investigate the relationship between active inflammatory lesions on whole-body MRI (wb-MRI) and new development of chronic lesions on T1 MRI in patients with early axial spondyloarthritis (SpA) treated either with etanercept (ETA) or sulfasalazine (SSZ). Methods Wb-MRIs of 65 patients treated either with ETA (n=35) or SSZ (n=30) over 1 year were scored for active inflammation, fatty lesions, erosions and ankylosis in the 23 vertebral units (VUs) of the spine and in the sacroiliac joints (SI joints). Scoring was performed by two blinded radiologists. Results If there was no previous inflammation in the bone no new fatty lesions occurred in SI joint quadrants and only a few (0.6%) in spine VUs. There was a significant relationship between disappearance of inflammation and the appearance of fatty lesions: if baseline inflammation resolved fatty lesions occurred in 10.5% of SI joint quadrants and 17.9% of VUs. If inflammation did not resolve over 1 year, fatty lesions occurred less frequently: 2.4% (SI joint quadrants) and 7.2% (VUs). There was a significantly higher increase of the mean fatty lesion score between baseline and week 48 in the ETA (4.0 vs 4.8 for the SI joints and 1.9 vs 2.7 for the spine) compared to the SSZ (3.0 vs 3.2 for the SI joints and 1.1 vs 1.2 for the spine, respectively) group (p=0.001 and p=0.020 for the differences). No significant changes in the erosion or ankylosis score were observed in any of the two groups during this time. Conclusions These data indicate that there is a close interaction between inflammation, tumour necrosis factor blockade and the development of fatty lesions in subchondral bone marrow of patients with axial SpA.

Knee Osteoarthritis Efficacy of a new method of contrast-enhanced musculoskeletal ultrasonography in detection of synovitis in patients with knee osteoarthritis in comparison with magnetic resonance imaging

Objective: To develop a new method of digital synovial vascularisation quantification by using contrast-enhanced musculoskeletal ultrasonography (MUS) in detecting synovitis in patients with knee osteoarthritis (OA) compared with healthy subjects and MRI. Methods: Evaluation of 41 patients with painful knee OA and 6 healthy subjects. The severity of knee pain was evaluated. All patients and all 6 healthy subjects underwent contrast medium-enhanced (CE)-MUS with SonoVue®, and 36 patients additionally underwent CE-MRI with Magnevist. Joint effusion, synovial thickening and pain were assessed and compared with B-mode and Power Doppler sonography (PDS) as well as contrast medium enhancement. Results: Pain evaluated by the visual analogue scale (VAS) hardly correlated with other markers of disease activity measured by ultrasound (US) in B-mode or MRI. US of the superior recess revealed an effusion or synovial thickening in 58%. PDS findings were positive in 63%, and CE-MUS in the superior knee recess was positive in 95%. MRI showed effusion in the superior recess in 61% and showed positive findings in 82% when using contrast medium. The kappa value was 0.48 between US and MRI with regard to the effusion in the superior recess, and 0.53 between PD signal in the superior recess and effusion in the superior recess by US. Using MRI as the reference standard, there was a sensitivity of 72% for assessing effusion in the superior recess and 81% for assessing effusion in the lateral recess. Conclusion: Assessment of disease activity (synovitis) in knee OA by VAS is not sufficient. US PDS was more sensitive than B-mode, and CE-MUS was more sensitive than PDS and CE-MRI in detecting synovitis in patients with painful knee OA. Also, CE-MRI was more sensitive in detecting inflammatory changes in the superior recess than without contrast medium. Using CE-MUS and performing time/intensity analysis has shown to be a good model for evaluation of an inflammatory process in the setting of knee OA in the superior recess.

Contrast-enhanced ultrasound in monitoring the efficacy of a bradykinin receptor 2 antagonist in painful knee osteoarthritis compared with MRI

Objectives: To evaluate contrast-enhanced ultrasound (CE-US) as a monitoring tool to assess hypervascularisation of synovial processes in knee osteoarthritis (OA) treated with intra-articular injections of the bradykinin-receptor 2 antagonist icatibant compared to contrast-enhanced magnetic resonance imaging (CE-MRI). Patients and methods: In a randomised, double-blind, placebo-controlled trial, 41 patients with painful knee OA underwent US (12.5 MHz for B-mode and 3–8 MHz for CE-US), and 36 of the patients underwent additional MRI (0.2T) at baseline and after 3 injections of the study drug (after a mean of 22.2 days). A total of 15 patients received placebo (group A), 12 patients 500 μg icatibant (group B) and 14 patients 2000 μg icatibant (group C). Pain and the synovial process (B-mode, power Doppler US (PD-US), CE-US, CE-MRI) were assessed at both time points. Results: At baseline, the placebo group showed more activity in terms of effusion in the superior and lateral recess in ultrasound as well as in PD-US in the lateral recess. Pain improved significantly in all subgroups. Effect sizes were 0.43 (pain at rest) and 0.52 (pain during activity) in group B vs 0.48 and 1.11 in group C. There was no change of US and MRI parameters. We found moderate to good correlation (r) and kappa values (κ) for effusion in the superior recess (r = 0.591, k = 0.453), effusion in the lateral recess (r = 0.304, k = 0.440) and contrast enhancement (r = 0.601, k = 0.242) between US and MRI. Conclusions: Our results show that CE-US and CE-MRI have good agreement in assessing inflammatory changes in knee OA. For the 41 patients with OA, an analgesic effect of icatibant could clearly be shown, especially for pain during activity in the high dose icatibant group. However, we could not find an anti-inflammatory effect of icatibant by CE-US compared to CE-MRI.

Very early spondyloarthritis: where the inflammation in the sacroiliac joints starts

Involvement of the sacroiliac joints (SIJ) is a major and characteristic feature of the spondyloarthritides (SpA). In early ankylosing spondylitis and undifferentiated SpA (uSpA) sacroiliitis is the most common early clinical finding and the presumed first manifestation of the disease. Magnetic resonance imaging has proved useful for visualising inflammation in the SIJ in adults and children. Recently, initial localisation of the inflammation in the SIJ has been described in some detail, but it has not been completely defined to date—either in imaging or in histopathological studies. This is mainly owing to the lack of data in very early disease and the lack of follow up studies. Here we present a patient with early disease, which may augment our understanding of this stage of SpA.

Bildgebung bei Spondylitis ankylosans

Neben den konventionellen Rontgenverfahren hat vor allem die Magnetresonanztomographie (MRT) Bedeutung fur Diagnostik und Management der Spondylitis ankylosans (AS). Wahrend die Rontgentechnik vorwiegend fur die Diagnostik chronischer struktureller Veranderungen geeignet ist, ermoglicht die MRT-Technik zusatzlich den Nachweis von aktiven entzundlichen Veranderungen.