Gemcitabine-Induced Myonecrosis Following Hypofractionated Radiation.

Palliative radiation is often used to abate pain and prevent bone fractures in patients with metastatic cancer. Hypofractionation, meaning delivery of larger doses of radiation in each treatment session (fraction), has become the standard of care in most cases. It not only reduces the burden on the medical system and facilitates the relief of symptoms but also enables the maintenance of the continuity of systemic therapy. Radiation recall phenomenon (RRP) is an acute inflammatory reaction in previously irradiated tissues that is provoked by chemotherapeutic drug administration. The incidence, severity, and prognosis of RRP following hypofractionated radiation therapy have not been studied. The symptoms of RRP depend on the radiation field, with the greatest concern associated with mucosal and dermal damage, though other symptoms have also been reported. Here, we describe a case of a 41-year-old woman with metastatic breast cancer (hormone receptor-positive, HER2/neu negative), who received palliative radiation to four other fields along the course of her disease, before her presentation with isolated myonecrosis of the thigh muscles. This RRP occurred four months following the last of two fractions of 8 Gy radiation to this region, given three months apart, and after six courses of cisplatin + gemcitabine. The symptoms improved with cessation of gemcitabine and prolonged administration of non-steroidal anti-inflammatory medications.

Sex-specific diagnostic efficacy of MRI in axial spondyloarthritis: challenging the 'One Size Fits All' notion.

OBJECTIVES: Sex-specific differences in the presentation of axial spondyloarthritis (axSpA) may contribute to a diagnostic delay in women. The aim of this study was to investigate the diagnostic performance of MRI findings comparing men and women. METHODS: Patients with back pain from six different prospective cohorts (n=1194) were screened for inclusion in this post hoc analysis. Two blinded readers scored the MRI data sets independently for the presence of ankylosis, erosion, sclerosis, fat metaplasia and bone marrow oedema. Χ2 tests were performed to compare lesion frequencies. Contingency tables were used to calculate markers for diagnostic performance, with clinical diagnosis as the standard of reference. The positive and negative likelihood ratios (LR+/LR-) were used to calculate the diagnostic OR (DOR) to assess the diagnostic performance. RESULTS: After application of exclusion criteria, 526 patients (379 axSpA (136 women and 243 men) and 147 controls with chronic low back pain) were included. No major sex-specific differences in the diagnostic performance were shown for bone marrow oedema (DOR m: 3.0; f: 3.9). Fat metaplasia showed a better diagnostic performance in men (DOR 37.9) than in women (DOR 5.0). Lower specificity was seen in women for erosions (77% vs 87%), sclerosis (44% vs 66%), fat metaplasia (87% vs 96%). CONCLUSION: The diagnostic performance of structural MRI markers is substantially lower in female patients with axSpA; active inflammatory lesions show comparable performance in both sexes, while still overall inferior to structural markers. This leads to a comparably higher risk of false positive findings in women.

Transient osteoporosis of the hip in pregnancy - a case series.

OBJECTIVE: Transient Osteoporosis of the Hip is a self-limiting disorder of severe hip joint pain presenting in pregnancy or postpartum, of which magnetic resonance imaging (MRI) is the modality of choice for diagnosis. Clinical data regarding transient osteoporosis of the hip is limited, precluding evidence-based decision-making such as recommended mode of delivery. In this case-series retrospective study, we aim to describe the natural course of transient osteoporosis of the hip during pregnancy and the postpartum period including implications of the mode of delivery. METHODS: All women diagnosed with unilateral/bilateral transient osteoporosis of the hip by MRI during pregnancy or postpartum between 2010 and 2019 at a single tertiary medical center were retrospectively studied. All MRI scans were reviewed by an experienced radiologist at the same single tertiary medical center. Data obtained from patients' electronic medical records and telephone questionnaires included maternal baseline characteristics, obstetric history, and current pregnancy obstetric and clinical outcome characteristics. Outcomes of normal vaginal delivery (NVD) and cesarean delivery (CD) were compared and analyzed. RESULTS: Thirty-four women were diagnosed with unilateral or bilateral transient osteoporosis of the hip during pregnancy (17 women) and postpartum (17 women). The mean maternal age was 34.18 ± 4.75 years. A family history of osteoporosis was reported in a rate of 29.4%. The rate of smokers was 47.1%, 32.4% of pregnancies were conceived by in-vitro fertilization (IVF), pre-pregnancy and term body mass index (BMI) were 22.03 and 27.6, respectively. No significant differences were found between NVD and CD in all parameters evaluated. Of 15 women with a sequential pregnancy, two were diagnosed with transient osteoporosis of the hip (13.3%). CONCLUSION: Women diagnosed with transient osteoporosis of the hip had advanced maternal age, low BMI, family history of osteoporosis, prevalent smoking and IVF pregnancies. Transient osteoporosis of the hip was bilateral in 25% and presented postpartum in 50% of cases. There was no significant difference in maternal outcomes between NVD and CD. Higher awareness of this potential diagnosis during pregnancy and postpartum may improve patient management and outcomes.

CT and MRI as Diagnostic and Management Decision Tools for First Time Lateral Patellar Dislocations: A Cross-Sectional, Retrospective Study.

Background: Following first-time lateral patellar dislocation (FTLPD), most patients are treated conservatively, although 50% of patients will have recurrent dislocations. Typically, radiographs followed by CT and/or MRI are used to assist the clinician in determining treatment strategy and, combined with clinical findings, intraarticular free bodies (CT/MRI), significant medial patellofemoral ligament (MPFL) tear (MRI) and lateral displacement of the patella (CT) form relative indications for surgery. Methods: Radiographs, MRI and CT knee studies of 34 patients after lateral patellar dislocation (26 FTLPD) were evaluated for intraarticular free bodies, patellar/trochlear fracture, lateral femoral condyle compression, MPFL tear, tibial tuberosity-trochlear groove (TT-TG) distance, and surgery indications. Free bodies and fractures were also evaluated on knee radiographs. FTLPD was analyzed as a subgroup. Surgical indications were compared between imaging modalities. Results: Among FTLPD (26 patients); free bodies were identified in 13 and 19 patients using MRI and CT respectively, compared with 5 patients on radiographs; this was statistically significant. In 8 cases surgery was indicated based on MPFL tear (MRI) combined with lateral patellar displacement (CT). When MRI and CT results were combined, 21 of 26 patients had imaging indications for surgery compared to 13 and 19 patients based on the MRI or CT alone, respectively.CT was statistically better than MRI alone or MRI with radiographs in identifying patients requiring surgery. Conclusion: An MRI or CT study is warranted to determine the need for surgery. A second imaging study (different from the first) should be considered, if surgical indication was not established from the initial study or clinical presentation.

Facet joint disease in patients with axial spondyloarthritis: A retrospective computed tomography study.

BACKGROUND: Facet joints' (FJ) ankylosis was reported in patients with radiographic axial spondyloarthritis (r-AxSpA). However, a detailed FJ evaluation over the whole spectrum of AxSpA was not performed. We aimed to analyze structural lesions in the FJ of patients with different forms of AxSpA, using computed tomography (CT). METHODS: CT studies of the cervical/thoracic/lumbar spine, or of the chest/abdomen of patients with r-AxSpA or non-radiographic AxSpA (nr-AxSpA) (age ≤ 50 years) were analyzed for the presence of erosions, ankylosis, joint-space narrowing, osteophytes, subchondral sclerosis, subchondral cysts and vacuum phenomenon. Age- and gender-matched subjects without known rheumatic disease who performed spinal CT, formed the control group. Findings were compared between groups, separately for each spinal segment. Further, FJ findings between three subgroups of the axSpA subjects, including r-AxSpA with or without syndesmophytes, and nr-AxSpA, were compared. RESULTS: 959/666 FJs (49/44 patients) were assessed in the AxSpA/control group patients, respectively. The study group consisted of 16 r-AxSpA patients with syndesmophytes and 22 r-AxSpA patients without syndesmophytes, and 11 nr-AxSpA patients. FJ ankylosis was significantly more prevalent in all spinal segments of the r-AxSpA patients with syndesmophytes. Erosions were seen almost exclusively in patients with r-AxSpA. Joint-space narrowing and osteophytes were noted in all segments and all subgroups of AxSpA patients, including those with nrAxSpA. CONCLUSIONS: Disease-specific FJ changes present almost exclusively in patients with r-AxSpA, while degenerative FJ changes are prevalent in all spinal segments and all AxSpA subgroups, suggesting that FJs can be affected early in the disease course.

Characterising axial psoriatic arthritis: correlation between whole spine MRI abnormalities and clinical, laboratory and radiographic findings.

OBJECTIVE: To describe the prevalence of inflammatory and structural lesions using whole spine MRI in patients with psoriatic disease, and to assess their correlation with clinical features and with axial spondyloarthritis (axSpA) classification criteria. METHODS: This retrospective analysis included patients with whole spine and sacroiliac joints (SIJ) MRI, selected from 2 populations: (1) active psoriatic arthritis (PsA), irrespective of axial symptoms; (2) psoriasis with confirmed or suspected PsA and axSpA symptoms. MRI spondylitis and/or sacroiliitis (MRI-SpA) was defined according to Assessment of Spondyloarthritis International Society (ASAS) consensus and by radiologist impression. Agreement between MRI-SpA and different inflammatory back pain (IBP) definitions (Berlin/ASAS/rheumatologist criteria) and the axSpA classification criteria were calculated considering MRI as gold standard. Logistic regression determined MRI-SpA-associated factors. RESULTS: 93 patients were analysed (69.9% PsA; 30.1% psoriasis). Back pain was present in 81.7%, defined as IBP in 36.6%-57%. MRI-SpA was found in 9.7% of patients by ASAS definition and in 12.9% by radiologist impression, of which 25% had isolated spondylitis.Low agreement was found between the three IBP definitions and MRI-SpA. Rheumatologist criteria was the most sensitive (50%-55.6%) while ASAS and Berlin criteria were the most specific (61.9%-63%). axSpA criteria had poor sensitivity for MRI-SpA (22.2%-25%). Late onset of back pain or asymptomatic patients accounted for most cases with MRI-SpA not meeting axSpA or IBP criteria. Male sex was associated with MRI-SpA (OR 6.91; 95% CI 1.42 to 33.59) in multivariable regression analysis. CONCLUSION: Prevalence of MRI-defined axSpA was low and showed poor agreement with IBP and axSpA criteria.

Ultrasound, magnetic resonance imaging and radiography of the finger joints in psoriatic arthritis patients.

OBJECTIVES: To report the discrepancies and agreements between US, MRI and radiography of the hand in PsA, and to compare the sensitivity and specificity of US and radiography to MRI as the gold standard imaging study in PsA. METHODS: All of the 100 prospectively recruited consecutive PsA patients underwent clinical assessment and concomitant radiographic, US and MRI studies of the MCP, PIP and DIP joints of one hand. Synovitis, flexor tenosynovitis, extensor paratenonitis, erosions and bone proliferations were identified and scored. All readers were blinded to clinical data, and agreement was calculated based on prevalence-adjusted bias-adjusted kappa (PABAK). RESULTS: The prevalence of synovitis, flexor tenosynovitis, extensor paratenonitis and erosions was similar for US and MRI, while that of bone proliferation was significantly increased in US and radiography compared with MRI (P < 0.001). The absolute agreement between US and MRI was good-to-very good for synovitis (85-96%, PABAK = 0.70-0.92), flexor tenosynovitis (93-98%, PABAK = 0.87-0.96) and extensor paratenonitis (95-98%, PABAK = 0.90-0.97). Agreement between US, MRI and radiography was 96-98% (PABAK = 0.92-0.97) for erosions and 71-93% (PABAK = 0.47-0.87) for bone proliferations. Sensitivity of US with MRI as gold standard was higher for synovitis (0.5-0.86) and extensor paratenonitis (0.63-0.85) than for flexor tenosynovitis (0.1-0.75), while the specificity was high for each pathology (0.89-0.98). CONCLUSION: There is very good agreement between US and MRI for the detection of inflammatory changes in finger joints in PsA. US, radiography and MRI have a good-to-very good agreement for destructive changes.

The prevalence of sacroiliitis on abdominal MRI examinations of patients with Takayasu arteritis.

BACKGROUND: Takayasu arteritis (TA), a systemic large-vessel vasculitis, was reported to have high incidence of spondyloarthropathy. PURPOSE: To evaluate the prevalence of inflammatory sacroiliitis in patients with TA that underwent abdominal/pelvic magnetic resonance imaging (MRI) examinations as part of their vasculitis work-up. MATERIAL AND METHODS: Consecutive abdominal/pelvic MRI examinations of 34 patients with TA fulfilling the 1990 ACR criteria and 34 age- and gender-matched controls performed between 2008 and 2020 were retrospectively reviewed for the presence sacroiliitis. The presence of active and structural lesions was scored twice (with a one-month interval between reads) by one reader. Structural lesions were also evaluated on computed tomography, when available, and correlated to MRI findings. Clinical data were extracted from the patients' clinical files. MRI scores were compared between the study and control groups and correlated with the clinical data. RESULTS: Sacroiliitis was evident in 11.7% of the TA group examinations compared to 0.3% in the control group (P = 0.6). Participants with TA had significantly more erosions and fat deposition compared to the control group (Study: 0.01/0.03, Control: 0/0, P = 0.03/0.003, respectively). However, mean sacroiliitis score was not significantly different (Study: 1.06, Control: 0.78, P = 0.015). Of the four patients with TA and sacroiliitis, 3 (75%) had a diagnosis of inflammatory bowel disease (IBD). CONCLUSION: Sacroiliitis was detected in 11.7% of abdominal MRI examinations of patients with TA, 75% of which had associated IBD, suggesting that both IBD and sacroiliitis should be routinely screened in the TA population as their presence may influence treatment decisions.

Approach to a patient with monoarticular disease.

PURPOSE: To reassess the diagnostic approach to a patient with a monoarticular disease in light of the up-to-date medical literature and to examine the practical utility of traditional and newer imaging tools in the setting of monoarthritis. RESULTS: The monoarticular disease can represent a medical emergency on the one hand and be a diagnostic conundrum on the other. The management rules of patients with monoarthritis have been established long ago, but various pitfalls still lead physicians off the right diagnosis at times. Septic, pseudoseptic arthritis and hemarthrosis are the most common diagnoses made in patients with an acute presentation, and a decision not to perform a diagnostic arthrocentesis is the most prevalent cause of misdiagnosis in this setting. Many rheumatic and infectious diseases can present with more indolent monoarthritis; careful history and physical examination frequently provide clues to the straightforward diagnosis in some cases, but the extensive investigation is needed in others. Imaging methods become indispensable in individuals with the non-inflammatory monoarticular disease, with magnetic resonance imaging being the gold standard for diagnosing pigmented villonodular synovitis, lipoma arborescence, avascular necrosis, or neuropathic arthropathy. CONCLUSIONS: A great variety of medical disorders can present as a monoarticular disease. The disease presentation dictates different diagnostic behavior, while knowing the available imaging methods' diagnostic potential should further shorten the diagnostic process.

Data-driven definitions for active and structural MRI lesions in the sacroiliac joint in spondyloarthritis and their predictive utility.

OBJECTIVES: To determine quantitative SI joint MRI lesion cut-offs that optimally define a positive MRI for inflammatory and structural lesions typical of axial SpA (axSpA) and that predict clinical diagnosis. METHODS: The Assessment of SpondyloArthritis international Society (ASAS) MRI group assessed MRIs from the ASAS Classification Cohort in two reading exercises where (A) 169 cases and 7 central readers; (B) 107 cases and 8 central readers. We calculated sensitivity/specificity for the number of SI joint quadrants or slices with bone marrow oedema (BME), erosion, fat lesion, where a majority of central readers had high confidence there was a definite active or structural lesion. Cut-offs with ≥95% specificity were analysed for their predictive utility for follow-up rheumatologist diagnosis of axSpA by calculating positive/negative predictive values (PPVs/NPVs) and selecting cut-offs with PPV ≥ 95%. RESULTS: Active or structural lesions typical of axSpA on MRI had PPVs ≥ 95% for clinical diagnosis of axSpA. Cut-offs that best reflected a definite active lesion typical of axSpA were either ≥4 SI joint quadrants with BME at any location or at the same location in ≥3 consecutive slices. For definite structural lesion, the optimal cut-offs were any one of ≥3 SI joint quadrants with erosion or ≥5 with fat lesions, erosion at the same location for ≥2 consecutive slices, fat lesions at the same location for ≥3 consecutive slices, or presence of a deep (i.e. >1 cm depth) fat lesion. CONCLUSION: We propose cut-offs for definite active and structural lesions typical of axSpA that have high PPVs for a long-term clinical diagnosis of axSpA for application in disease classification and clinical research.

Prevalence of Nonradiographic Sacroiliitis in Patients With Psoriatic Arthritis: A Real-life Observational Study.

OBJECTIVE: To establish the prevalence of nonradiographic sacroiliitis within a real-life sample of patients with psoriatic arthritis (PsA), using pelvic radiographs and magnetic resonance imaging (MRI) of sacroiliac joints (SIJs). METHODS: This cross-sectional study included 107 consecutive adults with PsA (Classification Criteria for Psoriatic Arthritis criteria). Participants completed clinical and laboratory evaluation, pelvic radiographs scored for radiographic sacroiliitis according to the modified New York (mNY) criteria, and noncontrast MRI of SIJs, scored by the Berlin score and categorized into active sacroiliitis using the 2016 Assessment of Spondyloarthritis international Society (ASAS) criteria and the presence of structural sacroiliitis. RESULTS: Radiographic sacroiliitis/mNY criteria were detected in 28.7% (n = 29), confirmed by MRI-detected structural lesions in 72.4% (n = 21). Active sacroiliitis was detected by MRI in 26% (n = 28) of patients, with 11% (n = 11) qualifying for nonradiographic sacroiliitis. Patients with radiographic and nonradiographic sacroiliitis had similar clinical characteristics, except for a longer duration of psoriasis (PsO) and PsA in the radiographic subgroup (PsO: 23.8 ± 12.5 vs 14.1 ± 11.7 yrs, P = 0.03; PsA: 12.3 ± 9.8 vs 4.7 ± 4.5 yrs, P = 0.02, respectively). Inflammatory back pain (IBP) was reported in 46.4% (n = 13) with active sacroiliitis and 27% (n = 3) with nonradiographic sacroiliitis. The sensitivity of IBP for detection of nonradiographic sacroiliitis was low (27%) and moderate for radiographic sacroiliitis (52%), whereas specificity ranged from 72% to 79% for radiographic and nonradiographic sacroiliitis, respectively. CONCLUSION: The prevalence of active sacroiliitis among a real-life population of patients with PsA was 26%. However, the prevalence of nonradiographic sacroiliitis was low (11%) compared to the radiographic sacroiliitis (28.7%) seen in patients with longer disease duration. IBP was not a sensitive indicator for the presence of early-stage sacroiliitis that was commonly asymptomatic.

Whole-body Magnetic Resonance Imaging in Psoriatic Arthritis, Rheumatoid Arthritis, and Healthy Controls: Interscan, Intrareader, and Interreader Agreement and Distribution of Lesions.

OBJECTIVE: Whole-body MRI (WBMRI) is a promising technique for monitoring patients' global disease activity in inflammatory joint diseases. The validation of WBMRI is limited; no studies have evaluated the test-retest agreement (interscan agreement) and only a few have assessed the intra- and interreader agreement. Therefore, we first examined the interscan agreement of WBMRI in patients with psoriatic arthritis (PsA), rheumatoid arthritis (RA), and healthy controls (HC); and second, we evaluated the intra- and interreader agreement and agreement with conventional hand MRI and determined the distribution of lesions. METHODS: WBMRI was performed twice at a 1-week interval in 14 patients with PsA, 10 with RA, and 16 HC. Images were anonymized and read in pairs with unknown chronological order by experienced readers according to the Outcome Measures in Rheumatology (OMERACT) WBMRI, Canada-Denmark MRI, and the RA MRI scoring system (RAMRIS) and the PsA MRI scoring system (PsAMRIS). Ten image sets were reanonymized for assessment of intra- and interreader agreement. Agreement was calculated on lesion level by percentage exact agreement (PEA) and Cohen κ, and for sum scores by absolute agreement, single-measure intraclass correlation coefficient (ICC). RESULTS: WBMRI of the spine and peripheral joints and entheses generally showed moderate to almost perfect interscan agreement with PEA ranging from 95% to 100%, κ 0.71-1.00, and ICC 0.95 to 1.00. Intra- and interreader data generally showed moderate to almost perfect agreement. Agreement with conventional MRI varied. More lesions were found in patients than in HC. CONCLUSION: WBMRI showed good interscan agreement, implying that repositioning of the patient between examinations does not markedly affect scoring of lesions. Intra- and interreader agreement were moderate to almost perfect.

Whole-Body Magnetic Resonance Imaging Assessment of Joint Inflammation in Rheumatoid Arthritis-Agreement With Ultrasonography and Clinical Evaluation.

Objective: To compare joint inflammation seen by whole-body magnetic resonance imaging (WBMRI), with "whole-body" ultrasound and clinical assessments, in patients with active rheumatoid arthritis (RA) before and during tumor necrosis factor-inhibitor (TNF-I, adalimumab) treatment. Methods: In 18 patients with RA, clinical assessment for joint tenderness and swelling, WBMRI, and ultrasound were obtained at baseline and week 16. Wrist, metacarpophalangeal (MCP) and proximal interphalangeal (PIP), elbow (except for WBMRI), shoulder, knee, ankle, and metatarsophalangeal joints were examined. Joint inflammation was defined by WBMRI as the presence of synovitis and/or osteitis and by ultrasound as gray-scale synovial hypertrophy grade >2 and/or color Doppler grade >1. On patient level, agreement was assessed by Spearman correlation coefficients (rho) for sum scores for 28 joints (i.e., wrists, MCPs, PIPs, elbows, shoulders, and knees) between clinical examination (DAS28CRP), ultrasound (US28), and WBMRI (WBMRI26; elbows not included). On joint level, agreement on inflammation between WBMRI, ultrasound, and clinical findings was calculated with Cohen's kappa (κ). Results: At patient level, WBMRI26 and US28 sum scores showed good correlation (rho = 0.72; p < 0.01) at baseline, but not at follow-up (rho = 0.25; p = 0.41). At joint level, moderate agreement was seen for hand joints (κ = 0.41-0.44); for other joints κ <0.40. No correlation with DAS28CRP was seen. No statistically significant correlations were observed between changes in WBMRI26, US28, and DAS28CRP during treatment. Conclusions: WBMRI and ultrasound joint inflammation sum scores at patient level showed good agreement in clinically active RA patients before TNF-I initiation, whereas agreement was poorer at joint level, and after treatment.

Atlas of the OMERACT Heel Enthesitis MRI Scoring System (HEMRIS).

OBJECTIVE: Assessment of enthesitis, a key feature in spondyloarthritis (SpA) and psoriatic arthritis (PsA), using objective and sensitive methods is pivotal in clinical trials. MRI allows detection of both soft tissue and intra-osseous changes of enthesitis. This article presents an atlas for the Outcome Measures in Rheumatology (OMERACT) Heel Enthesitis Magnetic Resonance ImagingMRI Scoring System (HEMRIS). METHODS: Following a preliminary selection of potential examples of each grade, as per HEMRIS definitions, the images along with detailed definitions and reader rules were discussed at web-based, interactive meetings between the members of the OMERACT MRI in Arthritis Working Group. RESULTS: Reference images of each grade of the MRI features to be assessed using HEMRIS, along with reader rules and recommended MRI sequences are depicted. CONCLUSION: The presented reference images can be used to guide scoring Achilles tendon and plantar fascia (plantar aponeurosis) enthesitis according to the OMERACT HEMRIS in clinical trials and cohorts in which MRI enthesitis is used as an outcome.

Imaging of diffuse idiopathic skeletal hyperostosis (DISH).

Diffuse idiopathic skeletal hyperostosis (DISH) is a condition characterised by calcification and ossification of ligaments and entheses. The condition usually affects the axial skeleton, in particular, at the thoracic segment, though also other portions of the spine are often involved. DISH often involves also peripheral tendinous and/or entheseal sites either alone, or in association with the involvement of peripheral joints. At times, new bone formation involves the bone itself, but sometimes it involves joints not usually affected by osteoarthritis (OA) which result in bony enlargement of the epiphysis, joints space narrowing and a reduced range of motion. Because of the entheseal involvement, DISH can be mistaken for seronegative spondyloarthropathies or for a "simple" OA. Furthermore, other implications for the recognition of DISH include spinal fractures, difficult intubation and upper endoscopies, decreased response rates in DISH with concomitant spondyloarthritides, and increased likelihood to be affected by metabolic syndrome and cardiovascular diseases. This Atlas is intended to show the imaging finding in DISH in patients diagnosed with the condition by the Resnick classification criteria.

MRI lesions in the sacroiliac joints of patients with spondyloarthritis: an update of definitions and validation by the ASAS MRI working group.

OBJECTIVES: The Assessment of SpondyloArthritis international Society (ASAS) MRI working group (WG) was convened to generate a consensus update on standardised definitions for MRI lesions in the sacroiliac joint (SIJ) of patients with spondyloarthritis (SpA), and to conduct preliminary validation. METHODS: The literature pertaining to these MRI lesion definitions was discussed at three meetings of the group. 25 investigators (20 rheumatologists, 5 radiologists) determined which definitions should be retained or required revision, and which required a new definition. Lesion definitions were assessed in a multi-reader validation exercise using 278 MRI scans from the ASAS classification cohort by global assessment (lesion present/absent) and detailed scoring (inflammation and structural). Reliability of detection of lesions was analysed using kappa statistics and the intraclass correlation coefficient (ICC). RESULTS: No revisions were made to the current ASAS definition of a positive SIJ MRI or definitions for subchondral inflammation and sclerosis. The following definitions were revised: capsulitis, enthesitis, fat lesion and erosion. New definitions were developed for joint space enhancement, joint space fluid, fat metaplasia in an erosion cavity, ankylosis and bone bud. The most frequently detected structural lesion, erosion, was detected almost as reliably as subchondral inflammation (κappa/ICC:0.61/0.54 and 0.60/0.83) . Fat metaplasia in an erosion cavity and ankylosis were also reliably detected despite their low frequency (κappa/ICC:0.50/0.37 and 0.58/0.97). CONCLUSION: The ASAS-MRI WG concluded that several definitions required revision and some new definitions were necessary. Multi-reader validation demonstrated substantial reliability for the most frequently detected lesions and comparable reliability between active and structural lesions.

Imaging to Differentiate the Various Forms of Seronegative Arthritis.

Spondyloarthritis (SpA) is a group of diseases characterized by back pain, spinal inflammation, human leukocyte antigen-B27 positivity, and peripheral findings such as dactylitis, enthesitis, and uveitis. It includes ankylosing spondylitis, psoriatic arthritis, reactive arthritis, arthritis associated with inflammatory bowel disease, and undifferentiated SpA. The role of imaging in the diagnosis, management, and follow-up of patients with SpA has become dramatically more important with the introduction of new therapies such as tumor necrosis factor-α inhibitors. Although in many instances differentiating between the SpA entities is straightforward based on the clinical presentation, often such differentiation remains challenging, and categorization of an individual patient into a subset of SpA can be difficult. Imaging, mainly radiography and magnetic resonance imaging, serves as an important diagnostic tool. Diseases in the spondyloarthritis complex share common presentation but at the same time may have distinct radiographic phenotypes. We present these common and distinct imaging manifestations that may potentially help distinguish between the entities in the diagnostic work-up.

Whole-body Magnetic Resonance Imaging in Axial Spondyloarthritis: Reduction of Sacroiliac, Spinal, and Entheseal Inflammation in a Placebo-controlled Trial of Adalimumab.

OBJECTIVE: To investigate whether adalimumab (ADA) reduces whole-body (WB-) magnetic resonance imaging (MRI) indices for inflammation in the entheses, peripheral joints, sacroiliac joints, spine, and the entire body in patients with axial spondyloarthritis (axSpA). METHODS: An investigator-initiated, randomized, placebo-controlled, double-blinded 48-week followup trial included 49 patients with axSpA, who had Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) ≥ 4.0 despite treatment with nonsteroidal antiinflammatory drugs and a clinical indication for tumor necrosis factor inhibitor treatment. Patients were randomized to subcutaneous ADA 40 mg or placebo every other week for 6 weeks; thereafter, all patients received ADA. Conventional MRI and WBMRI were performed at weeks 0, 6, 24, and 48. The primary WBMRI endpoint was the proportion of patients with an improvement in WBMRI total inflammation index above the smallest detectable change (SDC) at Week 6. RESULTS: The primary WBMRI endpoint (improvement of SDC > 2.3) was met in 11 (44%) patients in the ADA group and 3 (13%) patients in the placebo group (p = 0.025, Fisher's exact test). The primary conventional MRI endpoint, the minimally important change in Spondyloarthritis Research Consortium of Canada Spine MRI Inflammation Index at Week 6, was achieved by 9 (36%) patients in the ADA group and 4 (17%) patients in the placebo group (p = 0.20). The primary clinical endpoint, BASDAI reduction > 50% or 2.0 at Week 24, was attained by 32 (65%) patients. CONCLUSION: ADA provided significant reductions in WBMRI indices of peripheral, axial, and whole-body inflammation in patients with axSpA. WBMRI is promising for objective assessment and monitoring of peripheral and axial disease activity in future clinical trials.

Degenerative changes of the thoracic spine do exist in patients with diffuse idiopathic skeletal hyperostosis: a detailed thoracic spine CT analysis.

Background Degenerative intervertebral disease (DID) is an exclusion criterion in the Resnick and Niwayama radiographic classification for diffuse idiopathic skeletal hyperostosis (DISH). However, although DID was previously described in DISH, no systematic computed tomography (CT) analysis has been reported so far. Purpose To assess for the presence and prevalence of such changes on CT examinations of the thoracic spine of individuals with DISH. Material and Methods Intervertebral space (D1-L1) on chest CT examinations of DISH patients was retrospectively evaluated for the presence of DID. Parameters evaluated were disc space height, disc protrusion, subchondral cysts/sclerosis, Schmorl nodes, vacuum phenomenon, and posterior elements including costovertebral and facet joints. Parameters were compared with two age- and gender-matched control groups of individuals whose entire spine CT lacked evidence of DISH (Control 1 individuals < 2 flowing osteophytes, Control 2 individuals < 4 and ≥ 2 flowing osteophytes). Results A total of 158 participants (DISH/Control 1/Control 2 = 54/54/50; 106 men, 52 women; average age = 70.6 years) were evaluated. Average intervertebral disc height was significantly lower in the DISH group compared with both control groups (DISH/Control 1/Control 2 = 4.55/5.13/5.01 mm, P < 0.001). Costovertebral degenerative changes were more prevalent in DISH patients ( P < 0.05) and, except for vacuum phenomenon (more prevalent in controls), other DID changes were as prevalent in DISH as in controls. Conclusion The presence of degenerative intervertebral changes on thoracic CT should not deter from diagnosing DISH. Thus, the radiographic Resnick and Niwayama DISH criteria cannot be directly adapted to CT.