MRI of shoulder girdle in polymyalgia rheumatica: inflammatory findings and their diagnostic value.

BACKGROUND: Non-synovial inflammation as detected by MRI is characteristic in polymyalgia rheumatica (PMR) with potentially high diagnostic value. OBJECTIVE: The objective is to describe inflammatory MRI findings in the shoulder girdle of patients with PMR and discriminate from other causes of shoulder girdle pain. METHODS: Retrospective study of 496 contrast-enhanced MRI scans of the shoulder girdle from 122 PMR patients and 374 non-PMR cases. Two radiologists blinded to clinical and demographic information evaluated inflammation at six non-synovial plus three synovial sites for the presence or absence of inflammation. The prevalence of synovial and non-synovial inflammation, both alone and together with clinical information, was tested for its ability to differentiate PMR from non-PMR. RESULTS: A high prevalence of non-synovial inflammation was identified as striking imaging finding in PMR, in average 3.4±1.7, mean (M)±SD, out of the six predefined sites were inflamed compared with 1.1±1.4 (M±SD) in non-PMR group, p<0.001, with excellent discriminatory effect between PMR patients and non-PMR cases. The prevalence of synovitis also differed significantly between PMR patients and non-PMR cases, 2.5±0.8 (M±SD) vs 1.9±1.1 (M±SD) out of three predefined synovial sites, but with an inferior discriminatory effect. The detection of inflammation at three out of six predefined non-synovial sites differentiated PMR patients from controls with a sensitivity/specificity of 73.8%/85.8% and overall better performance than detection of synovitis alone (sensitivity/specificity of 86.1%/36.1%, respectively). CONCLUSION: Contrast-enhanced MRI of the shoulder girdle is a reliable imaging tool with significant diagnostic value in the assessment of patients suffering from PMR and differentiation to other conditions for shoulder girdle pain.

Magnetic resonance imaging in polymyalgia rheumatica-contrast enhancement is not always needed.

BACKGROUND: Extracapsular inflammation at entheseal sites in the pelvic girdle as demonstrated by magnetic resonance imaging (MRI) was shown to be useful as an additional tool for diagnosing polymyalgia rheumatica (PMR). However, it is unclear whether MRI needs to be performed with contrast enhancement or whether oedema-sensitive sequences are sufficient. OBJECTIVE: To evaluate the performance of T2w TIRM (turbo inversion recovery magnitude) imaging compared to fat-saturated contrast-enhanced (ce) T1w at predefined pelvic sites to detect extracapsular inflammation in patients with PMR. METHODS: A total of 120 pelvic MRIs of patients with pelvic girdle pain, 40 with clinically diagnosed PMR and 80 controls, were retrospectively scored by three blinded radiologists separately evaluating the MRI with and without contrast enhancement at 19 previously defined pelvic structures. The intra- and interrater reliability and the diagnostic performance of both techniques were statistically analysed and evaluated. RESULTS: The detection of inflammatory MRI signals correlated moderately between both techniques (Cohen's κ 0.583). With ceT1w imaging 20.7% more sites were detected as inflamed compared to T2w TIRM in PMR patients. Inter- and intrareader reliability was superior with ceT1w imaging. If the inflammatory signal was detected at three sites bilaterally including the origin of the rectus femoris muscle or adductor longus muscle, the sensitivity and specificity was 100% and 97.1% by ceT1w imaging vs. 80.8% and 93.3% by T2w TIRM, respectively. CONCLUSION: Contrast enhancement is superior to oedema-sensitive MRI in the detection of extracapsular inflammation in PMR. However, using T2w TIRM also detects many but not all PMR cases.

High Prevalence of Foot Insufficiency Fractures in Patients With Inflammatory Rheumatic Musculoskeletal Diseases.

OBJECTIVE: To assess the prevalence of foot insufficiency fractures (IF) in patients with rheumatic musculoskeletal disease (RMD) with foot pain. METHODS: In a retrospective design, 1752 magnetic resonance imaging (MRI) scans of consecutive patients presenting with foot pain in 2 time periods between 2016 and 2018 were evaluated. The group with IF was matched with controls with foot pain without IF. Bone mineral density (BMD) was assessed by dual-energy x-ray absorptiometry. Multivariate analyses were performed. RESULTS: A total of 1145 MRI scans of patients (median age 59 yrs, 82.9% female) with an inflammatory (65.4%) and of 607 with no inflammatory (34.6%) RMD (median age 58 yrs, 80.8% female) were available. Most patients had rheumatoid arthritis (RA; 42.2%), and others had psoriatic arthritis (22.4%), axial spondyloarthritis (11.1%), or connective tissue disease (CTD; 7.6%). Foot IF were found in 129 MRI scans of patients (7.5%). There was no difference between time periods. The prevalence of IF was highest in CTD (23%) and RA (11.4%). More patients with an inflammatory than a noninflammatory RMD had IF (9.1% vs 4.1%, respectively; P < 0.001). Using conventional radiography, IF were only detected in 25%. Low BMD and a history of fractures were more frequent in patients with IF than without (42.6% vs 16.2% and 34.9% vs 8.6%, respectively; P < 0.001). CONCLUSION: A high prevalence of foot fractures was found in MRI scans of patients with RMD, many without osteoporosis. MRI was more sensitive than radiographs to detect IF.

The influence of age on the prevalence of inflammatory and structural MRI lesions in the sacroiliac joints of patients with and without axial spondyloarthritis.

OBJECTIVES: To compare the influence of age on inflammatory (bone marrow oedema [BME]) and structural (fat lesions [FL], erosions and ankylosis) MRI lesions in the sacroiliac joints (SIJ) of patients with and without axial spondyloarthritis (axSpA). METHODS: In a retrospective study, SIJ MRI (STIR/T1 sequences) of consecutive patients with chronic back pain diagnosed with axSpA or non-SpA were evaluated based on SIJ quadrants (SIJ-Q). Two blinded readers evaluated BME and structural lesions. Reader agreement was evaluated for prevalence of MRI lesions related to age. RESULTS: MRIs of 309 (175 axSpA, 134 non-SpA) patients were evaluated. Their mean age was 38.5 (11.4) and 43.4 (13.8) years, 67% and 36% were male, CRP was 1.6 (2.4) and 1.1 (2.1) mg/dl and median symptom duration was 48 and 60 months for axSpA and non-SpA, respectively. SIJ-Q with BME and erosions were significantly more frequent in axSpA vs non-SpA patients independent of age, while this difference was seen for FL only in patients ≥50 years. The proportion of patients with ≥1 or ≥3 BME or chronic lesions except for FL increased with age in both groups, and was constantly higher in axSpA vs non-SpA. In univariate analyses, only female sex was significantly associated with more FL. CONCLUSIONS: The proportion of patients with MRI lesions was high in both axSpA and non-SpA patients. However, the prevalence of BME and erosions was significantly more frequent in patients with axSpA, was independent of age and also allowed for discrimination. FL occurred more frequently only in older age groups and were less reliable for discrimination vs non-SpA patients.

Early recognition of patients with axial spondyloarthritis-evaluation of referral strategies in primary care.

OBJECTIVE: Chronic inflammatory back pain (IBP) is frequently reported in axial SpA (axSpA) but also in the general population. We evaluated a recently proposed two-step referral system for early recognition of axSpA in primary care and compare it with other combinations of symptoms and SpA-related items. METHODS: Consecutive chronic back pain patients ≤45 years of age answered a questionnaire and were seen by a primary care physician who decided whether HLA-B27 needed to be determined. They were then referred to a rheumatologist who made the diagnosis. Generally sticking to the two-step system with HLA-B27 as an additional option, combinations with a sensitivity ≥90% and a likelihood ratio >4 were compared. RESULTS: A total of 326 patients were included, 46 of whom were diagnosed with axSpA (14.1%). The sensitivity of the strategy was 87%, the specificity was 56.8% and the positive and negative predictive values were 24.8% and 96.4%, respectively. A 'good response to NSAIDs', 'morning stiffness >30 min' and 'elevated C-reactive protein' performed best, with a sensitivity of 91%, specificity of 67%, positive predictive value of 31% and negative predictive value of 98%. On that basis, only three patients had to be seen by a rheumatologist to diagnose one. CONCLUSION: The earlier proposed referral system worked well but was outperformed by other combinations with high sensitivity and better specificity, which deserve to be prospectively studied.

Diagnostic capability of contrast-enhanced pelvic girdle magnetic resonance imaging in polymyalgia rheumatica.

OBJECTIVE: There is currently no diagnostic test for PMR. A characteristic pattern of extracapsular inflammation as assessed by contrast-enhanced MRI (ceMRI) has recently been described in the pelvis of patients with PMR. We aimed to evaluate the performance of inflammatory ceMRI signals at predefined pelvic sites as a diagnostic test for PMR. METHODS: Pelvic MRI scans of patients with pelvic girdle pain (n = 120), including 40 patients with an expert diagnosis of PMR and 80 controls with other reasons for pelvic pain were scored by three blinded radiologists, who evaluated the degree of contrast enhancement at 19 predefined tendinous and capsular pelvic structures. Different patterns of involvement were analysed statistically. RESULTS: The frequency of bilateral peritendinitis and pericapsulitis including less common sites, such as the proximal origins of the m. rectus femoris and m. adductor longus, differed significantly between PMR cases and controls: 13.4 ± 2.7 vs 4.0 ± 2.3. A cut-off of ≥10 inflamed sites discriminated well between groups (sensitivity 95.8%, specificity 97.1%). Bilateral inflammation of the insertion of the proximal m. rectus femoris or adductor longus tendons together with ≥3 other bilaterally inflamed sites performed even better (sensitivity 100%, specificity 97.5%). CONCLUSION: This study confirms that a distinctive MRI pattern of pelvic inflammation (bilateral peritendinitis and pericapsulitis and the proximal origins of the m. rectus femoris and m. adductor longus) is characteristic for PMR. The high sensitivity and specificity of the set of anatomical sites evaluated suggests their clinical usefulness as a confirmatory diagnostic test.

Use of contrast-enhanced magnetic resonance imaging of the pelvis to describe changes at different anatomic sites which are potentially specific for polymyalgia rheumatica.

OBJECTIVES: To identify inflammatory pelvic structures of patients with polymyalgia rheumatica (PMR) by magnetic resonance imaging (MRI) in detail, searching for a disease-specific pattern. METHODS: A total of 40 contrast-enhanced pelvic MRIs of patients with a clinical diagnosis of PMR was reviewed by an experienced musculoskeletal radiologist who assessed all abnormalities semi-quantitatively, based on a predefined scoring system. RESULTS: The median (25th/75th percentiles) age of patients was 67 (55/73) years, median symptom duration 13 (6/22) weeks, 55% female, median CRP 1.9 (0.7/4) mg/dl, median ESR 30/1h (17/43). Ten patients were diagnosed with rheumatoid arthritis (25%), in addition to their leading polymyalgic symptom. Multi-locular, mostly bilateral, peritendinous enhancement of pelvic girdle tendons was found to be the hallmark of PMR in all patients. Low-grade hip synovitis was also detected frequently. In all cases, ≥4 extracapsular tendinous sites were bilaterally affected. Besides involvement of the common ischiocrural tendon and the glutaeus medius and minimus tendon (present in all cases), an enhancement of the proximal rectus femoris origin was observed in 100% and of the adductor muscles at the inferior medial pubic bone in 90% of cases. The observed MRI pattern patho-anatomically suggests inflammation of the external peritendineum. CONCLUSIONS: The uniformity of the observed pelvic inflammatory pattern detected by contrast-enhanced MRI in PMR patients suggests that it may become relevant for diagnostic purposes. The bilateral involvement of at least 4 extracapsular sites (including the origins of proximal rectus femoris or adductorial muscles) appears to be characteristic of PMR.

Imaging of axial spondyloarthritis. New aspects and differential diagnoses.

Axial spondyloarthritis (axSpA) is a chronic rheumatic disease characterised by inflammatory back pain and several other disease manifestations and comorbidities. The 2009 ASAS classification criteria differentiate between the classical ankylosing spondylitis or radiographic axSpA and non-radiographic axSpA based on the presence or absence of definite radiographic changes in the sacroiliac joints. Importantly, back pain in patients with axSpA may well have reasons other than axial inflammation or new bone formation. There are several important differential diagnoses such as diffuse idiopathic skeletal hyperostosis and osteitis condensans. This review summarises recent publications concerning the performance of imaging modalities in the field, such as conventional radiography, magnetic resonance imaging, computed tomography and dual energy x-ray absorptiometry including the trabecular bone score.

The role of 18F-FDG positron emission tomography for the diagnosis of vasculitides.

Large-vessel vasculitis is the most common form of primary vasculitis comprising cranial and large-vessel giant cell arteritis, Takayasu's arteritis and idiopathic aortitis. Prompt diagnosis and treatment of large-vessel vasculitis are important to prevent potentially serious emergencies such as visual loss, vascular stenosis and aneurysm formation. Temporal artery biopsy has long been the standard for diagnosing GCA - an invasive technique that lacks sensitivity compared to a clinical diagnosis that relies on a combination of clinical symptoms, elevated serum inflammatory markers and imaging findings. Conventional angiography focussing on the detection of arterial stenoses and occlusion does not assess vessel wall changes. Therefore, angiography is being increasingly replaced by newer imaging modalities such as magnetic resonance imaging and 18F-FDG positron emission tomography-computed tomography. However, imaging modalities also including ultrasound are not uniformly used for diagnosis and monitoring of large-vessel vasculitis in clinical practice. Very recently recommendations for imaging have been developed by the European League Against Rheumatism and the Society of Nuclear Medicine and Molecular Imaging in cooperation with the European Association of Nuclear Medicine and an interest group endorsed by the American Society of Nuclear Cardiology. These and a small literature search using PubMed are the basis for this review.

Intracranial aneurysms: role of multidetector CT angiography in diagnosis and endovascular therapy planning.

PURPOSE: To evaluate the sensitivity of 16-detector row computed tomographic (CT) angiography in diagnosis of intracranial aneurysms and to determine whether multidetector CT angiography provides sufficient diagnostic information to guide endovascular treatment, with combined imaging and clinical data as the reference standard. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. Eighty-seven patients clinically suspected of having subarachnoid hemorrhage underwent multidetector CT angiography and digital subtraction angiography (DSA). Aneurysm detection with multidetector CT angiography and DSA was analyzed on a per-patient and a per-aneurysm basis. For each aneurysm deemed ruptured on multidetector CT angiograms, the same multidetector CT angiography data set was used to determine whether the aneurysm was suitable for endovascular coil placement or whether a neurosurgical procedure was preferable. Criteria were based on neck width in relation to aneurysm size and the presence of vessels originating from the aneurysm. Results were compared with actual treatment that had been performed in each aneurysm after full diagnostic work-up, including DSA. Sensitivity, specificity, and positive and negative predictive values for aneurysm presence were determined. RESULTS: The reference standard revealed 84 aneurysms in 63 patients. Multidetector CT angiography was used to correctly identify 62 of 63 patients with 80 of 84 aneurysms and to correctly rule out aneurysms in 24 patients. DSA was used to correctly identify 62 of 63 patients with 79 of 84 aneurysms and to correctly rule out aneurysms in 23 patients. Per patient, the sensitivity, specificity, and positive and negative predictive values, respectively, for presence of aneurysm(s) were 98%, 100%, 100%, and 96% for multidetector CT angiography and 98%, 100%, 98%, and 96% for DSA. Per aneurysm, the possibility of coil embolization was correctly assessed with multidetector CT angiography in 69 (93%) of 74 target aneurysms for acute occlusive treatment. CONCLUSION: Multidetector CT angiography offers high diagnostic accuracy-equivalent to that of DSA-in the detection of intracranial aneurysms. Also, the possibility of coil embolization can be reliably determined with multidetector CT angiography.