Predictive Value of Magnetic Resonance Imaging in Patients With Juvenile Idiopathic Arthritis in Clinical Remission.

OBJECTIVE: To define the prevalence of subclinical synovitis on magnetic resonance imaging (MRI) in a large cohort of patients with juvenile idiopathic arthritis (JIA) in clinical remission and to evaluate its predictive value in terms of disease flare and joint deterioration. METHODS: Ninety patients with clinically inactive JIA who underwent a contrast-enhanced (CE)-MRI of a previously affected joint were retrospectively included. Each joint was evaluated for synovitis, tenosynovitis, and bone marrow edema. Baseline and follow-up radiographs were assessed to evaluate structural damage progression. RESULTS: CE-MRI was acquired in 45 wrists, 30 hips, 13 ankles, and 2 knees. Subclinical synovitis was detected in 59 (65.5%) of 90 patients and bone marrow edema in 42 (46.7%) of 90 patients. Fifty-seven of 90 (63.3%) patients experienced a disease flare during follow-up. Forty-four of 59 (74.6%) patients with subclinical synovitis experienced a disease flare versus 13 (41.9%) of 31 patients with no residual synovitis on MRI (P = 0.002). The presence of subclinical synovitis was the best predictor of disease flare on multivariable regression analysis (hazard ratio [HR] 2.45, P = 0.003). Baseline and follow-up radiographs were available for 54 patients, and 17 (31.5%) of 54 patients experienced radiographic damage progression. The presence of bone marrow edema (HR 4.40, P = 0.045) and being >17 years old (HR 3.51, P = 0.04) were strong predictors of joint damage progression in the multivariable analysis. CONCLUSION: MRI-detected subclinical inflammation was present in a large proportion of patients with JIA despite clinical remission. Subclinical synovitis and bone marrow edema have been shown to play a role in predicting the risk of disease relapse and joint deterioration, with potential implications for patients' management of the disease.

Effect of the Inclusion of the Metacarpophalangeal Joints on the Wrist Magnetic Resonance Imaging Scoring System in Juvenile Idiopathic Arthritis.

OBJECTIVE: To extend the magnetic resonance imaging (MRI) score for assessment of wrist synovitis in juvenile idiopathic arthritis (JIA) by inclusion of the metacarpophalangeal (MCP) joints, and to compare the metric properties of the original and the extended score. METHODS: Wrist MRI of 70 patients with JIA were scored by 3 independent readers according to (1) the wrist component of the rheumatoid arthritis MRI synovitis score (comprising distal radioulnar, radiocarpal, and combined midcarpal and carpometacarpal joints); and (2) an extended score including the MCP joints. Thirty-eight patients had a 1-year MRI followup. The concordance between the readers [intraclass correlation coefficient (ICC), 95% limits of agreement (LOA), and weighted Cohen's κ], correlations with clinical variables (Spearman's ϱ), and the sensitivity to change [standardized response mean (SRM)] were calculated for both scores. RESULTS: The interreader agreement was moderate for the original score (ICC 0.77; 95% CI 0.68-0.84) and good for the extended score (ICC 0.86; 95% CI 0.80-0.91). Using 95% LOA, the aggregate score variability was less favorable with relatively wide LOA. Weighted Cohen's κ of the individual joints indicated good agreement for the original score and good to excellent agreement for the extended score. Correlations with clinical variables reflecting disease activity improved for the extended score and its SRM was higher compared to that of the original score. CONCLUSION: The extended score showed better reliability, construct validity, and sensitivity to change than the original. Inclusion of the MCP joints should be considered for a more accurate assessment of disease activity and treatment efficacy in JIA.

Ultrasound changes in synovial abnormalities induced by treatment in juvenile idiopathic arthritis.

OBJECTIVES: To investigate the capacity of ultrasound (US) to detect improvement of synovial abnormalities induced by treatment in juvenile idiopathic arthritis (JIA). METHODS: Eighty-three joints (33 knees, 22 tibiotalar, 10 wrists, 9 elbows, 9 subtalar joints) of 33 patients with new-onset JIA were assessed by US at study entry and 6 months after a therapeutic intervention. Each joint was scored for grey-scale (GS) and power Doppler (PD) abnormalities according to a 4-point semiquantitative scale. Pre- and post-treatment US scores were compared and the sensitivity to change of GSUS and PDUS was estimated. Clinical response was assessed using the ACR paediatric (ACRp) response criteria. RESULTS: Seventeen patients (51.5%) underwent intra-articular corticosteroid injection (IACI) only, 15 (45.5%) were given IACI and systemic medications, and 1 (3.0%) was started with systemic therapy alone. Both GSUS and PDUS scores improved significantly (p<0.0001) from baseline to follow-up. US revealed strong sensitivity to change with standardised response mean for GSUS and PDUS of 2.44 and 1.23, respectively. At the follow-up visit, 13/20 (65.0%) joints with residual US abnormalities were judged in remission on clinical grounds. Six/21 (28.6%) patients who were ACRp90 responders did not display complete resolution of synovial abnormalities on US. CONCLUSIONS: US is a sensitive tool to assess therapeutic response in patients with JIA. Subclinical disease on US is common in joints with clinically-defined remission. An ACRp90 response may not be coupled with complete resolution of synovial abnormalities on US. Further studies are needed to establish the impact of US on therapeutic decision-making in JIA.

Whole-body MRI: non-oncological applications in paediatrics.

Whole-body magnetic resonance imaging (WBMRI) is a fast and accurate method for detecting and monitoring of diseases throughout the entire body without exposure to ionizing radiation. Among emerging non-oncological potential applications of WBMRI, rheumatological diseases play an important role. Rheumatological WBMRI applications include the evaluation of chronic multifocal recurrent osteomyelitis, dermatomyositis, fever of unknown origin, arthritis, and connective tissue diseases. Aim of this review is to give an overview of the use of WBMRI in rheumatological field.

Delineating the Application of Ultrasound in Detecting Synovial Abnormalities of the Subtalar Joint in Juvenile Idiopathic Arthritis.

OBJECTIVE: To investigate the frequency of ultrasound (US)-detectable involvement of the subtalar joint (STJ), to compare clinical versus US assessment of the STJ, and to compare different scanning approaches to the STJ in juvenile idiopathic arthritis (JIA). METHODS: Clinical and US assessments were performed independently in 50 ankles with clinically active JIA. US abnormalities of the STJ were investigated using a lateral, medial, and posterior scanning approach and scored semiquantitatively. Agreement was tested using kappa statistics. A control group of 10 healthy subjects was examined. RESULTS: Clinical and US evaluations detected synovitis in 24 of 50 (48.0%) and 27 of 50 (54.0%) of STJs, respectively. US detected synovitis in 10 of 26 STJs (38.5%) recorded as normal on clinical evaluation, but was negative in 7 of 24 STJs (29.2%) diagnosed as having involvement on clinical examination. Agreement between clinical and US assessments was fair (κ = 0.32). US abnormalities were more frequently detectable using the lateral scanning approach. All patients with US abnormalities in the medial and/or posterior side of the STJ had also US abnormalities on the lateral scanning approach, but the reverse was not true. Intra- and interobserver agreements for the lateral scanning approach were satisfactory for both detecting involvement and scoring US abnormalities. None of the 17 STJs of healthy controls showed US abnormalities. CONCLUSION: US may increase the precision of the evaluation of the STJ in JIA. The observed high frequency of STJ involvement on US suggests to include this joint in US scanning protocols devised for children with JIA. Synovitis is more frequently detected using the lateral scanning approach.

Agreement among musculoskeletal pediatric specialists in the assessment of radiographic joint damage in juvenile idiopathic arthritis.

OBJECTIVE: To evaluate agreement among musculoskeletal pediatric specialists in assessing radiographic joint damage in juvenile idiopathic arthritis (JIA). METHODS: Two pediatric rheumatologists, 2 pediatric radiologists, and 2 pediatric orthopedic surgeons evaluated independently 60 radiographs of both wrists and hands of children with polyarticular-course JIA. Films were scored using an adapted and simplified version of the Larsen score, ranging from 0-5. Study radiographs were selected from 568 films used in a previous study aimed to validate an adapted pediatric version of the Sharp/van der Heijde (SHS) score. To enable comparison of specialists' scores with the adapted SHS score, the 60 radiographs were divided into 6 classes of severity of damage based on quintiles of the adapted SHS score. Agreement was evaluated in terms of absolute agreement and through weighted kappa statistics. RESULTS: The pediatric radiologists tended to assign lower scores and to provide more frequently scores of 0 than did the other specialists. Weighted kappa for the 3 pairs of specialists ranged from 0.67-0.69, indicating substantial agreement. Absolute agreement ranged from 51.3-55.7%, depending on the pair of specialists examined. Both absolute and weighted kappa concordance between specialists' scores and the adapted SHS score were poorer for the pediatric radiologist than for the other specialists. CONCLUSION: We observed fair agreement in the assessment of radiographic damage among pediatric specialists involved in the care of children with JIA. The radiologists tended to be more reserved than the rheumatologists and orthopedic surgeons in labeling radiographs as damaged or in considering changes as important.

Hemifacial spasm can be the presenting symptom of a fourth ventricle tumour. A short case-illustrated review and pathogenetic considerations.

In this short case-illustrated review we aimed to analyse the possible nuances of hemifacial spasm (HFS) as the presenting symptom of a tumour of the fourth ventricle. The issue is remarkable since HFS can be secondary to a fourth ventricle tumour, even when no other neurological signs are reported. In addition, the possible presentation with only upper facial muscle involvement, as in the presented case, can be deceitful because this is characteristic of the benign and much more frequent "typical" form. Based on our intra-operative data and on the previously reported cases, we think that pathogenesis could be referable to the facial nerve nucleus involvement and that clinical nuances could be related to the specific somatotropy of the nucleus under the fourth ventricle floor that, as in our case, can be infiltrated by tumour. Resolution of the disorder can usually be obtained after the complete resection of the tumour that in the reported case resulted a subependymoma (WHO grade I), so far never described in literature associated with HFS.

Dynamic contrast-enhanced magnetic resonance imaging in the assessment of disease activity in patients with juvenile idiopathic arthritis.

OBJECTIVE: To determine the capability and reliability of dynamic contrast-enhanced MRI (DCE-MRI) in the assessment of disease activity in juvenile idiopathic arthritis (JIA). METHODS: DCE-MRI of the clinically more affected wrist or hip joints was undertaken in 21 patients, coupled with standard clinical assessment and biochemical analysis. Synovial inflammation was assessed by computing the maximum level of synovial enhancement (ME), the maximum rate of enhancement (MV) and the rate of early enhancement (REE) from the enhancement curves generated from region of interest independently delineated by two readers in the area of the ME. Correlations between dynamic parameters and clinical measures of disease activity, and static MRI synovitis score were investigated. RESULTS: In patients with wrist arthritis, REE correlated with the wrist swelling score (r(s) = 0.72), ESR (r(s) = 0.69), pain assessment scale (r(s) = 0.63) and childhood HAQ (r(s) = 0.60). In patients with hip arthritis, ME correlated with the hip limitation of motion (r(s) = 0.69). Static MRI synovitis score based on post-gadolinium enhancement correlated with MV (r(s) = 0.63) in patients with wrist arthritis and with ME (r = 0.68) in those with hip arthritis. The inter-reader agreement assessed by intra-class correlation coefficient (ICC) for ME, MV and REE (ICC = 0.98, 0.97 and 0.84, respectively) was excellent. CONCLUSIONS: DCE-MRI represents a promising method for the assessment of disease activity in JIA, especially in patients with wrist arthritis. As far as we know, this study is the first to demonstrate the feasibility, reliability and construct validity of DCE-MRI in JIA. These results should be confirmed in large-scale longitudinal studies in view of its further application in therapeutic decision making and in clinical trials.

Magnetic resonance imaging, ultrasonography, and conventional radiography in the assessment of bone erosions in juvenile idiopathic arthritis.

OBJECTIVE: To compare magnetic resonance imaging (MRI), conventional radiography, and ultrasonography in identifying bone erosions in patients with juvenile idiopathic arthritis (JIA), and to determine the validity and reliability of an MRI scale in detecting and grading joint damage. METHODS: In 26 JIA patients, the clinically more affected wrist was studied with MRI, radiography, and ultrasonography, coupled with standard clinical assessment and biochemical analysis. MR images were assessed independently by 2 readers according to an apposite devised scoring system. RESULTS: Of 26 patients, 25 (96.1%) had 1 or more erosions as detected by MRI, whereas conventional radiography and ultrasonography revealed erosions in 13 (50%) of 26 and 12 (50%) of 24 patients, respectively. The ability of MRI to detect erosive changes was significantly higher with respect to conventional radiography (P = 0.002 with Bonferroni correction [P(B)]) and ultrasonography (P(B) = 0.0002) in the group of patients with <3 years' disease duration. Ultrasonography and conventional radiography were of equivalent value for the detection of destructive changes. Wrist MRI score correlated highly with radiographic erosion score (r(s) = 0.82) and with wrist limited range of motion score (r(s) = 0.69). The interreader intraclass correlation coefficient (ICC) for MRI score was excellent (0.97); intrareader ICCs were good for both investigators (0.97 and 0.79). CONCLUSION: MRI seems to be a powerful tool to detect early structural damage in JIA. The proposed MRI scale for bone erosions appears promising in terms of reliability and construct validity. The pathophysiologic meaning and the prognostic value of bone erosions revealed only by MRI remain to be established in longitudinal studies.

Dynamic gadolinium-enhanced magnetic resonance imaging of the wrist in patients with rheumatoid arthritis can discriminate active from inactive disease.

OBJECTIVE: To determine the efficacy of dynamic gadolinium-enhanced magnetic resonance imaging (MRI) of the wrist in the evaluation of disease activity in patients with rheumatoid arthritis (RA). METHODS: Thirty-six patients with RA (with different degrees of disease activity) and 5 healthy controls were studied. MRI was performed with a low-field (0.2T), extremity-dedicated machine. After an intravenous bolus injection of gadolinium-diethylenetriamine pentaacetic acid, 20 consecutive fast spin-echo images of 3 slices of the wrist were obtained every 18 seconds. RESULTS: The curves of synovial membrane enhancement identified the following 2 groups: controls and RA patients in remission, and RA patients with active or intermediately active disease. Both the rate of early enhancement (REE) and relative enhancement (RE) were significantly higher in patients with active RA than in those with inactive RA and controls. The REE and RE were significantly correlated with the number of swollen joints (P < 0.00001 and P = 0.003, respectively), the number of tender joints (P < 0.00001 and P = 0.004, respectively), the Ritchie index (P = 0.0002 for both REE and RE), the Disease Activity Score (P = 0.0004 and P = 0.0008, respectively), the Health Assessment Questionnaire (HAQ) (P = 0.0002 and P = 0.0007, respectively), early morning stiffness (P = 0.001 and P = 0.009, respectively), the C-reactive protein level (P = 0.015 and P = 0.03, respectively), the erythrocyte sedimentation rate (P = 0.03, RE only), and alpha2 globulins (P = 0.036 and P = 0.028, respectively). CONCLUSION: Our data support use of dynamic MRI for discriminating active from inactive RA. Enhancement curves are associated not only with laboratory and clinical indicators of inflammation, but also with the HAQ, a relevant predictor of RA functional outcome. This technique can be repeated frequently and is an excellent candidate for the ideal method for the followup of patients with RA.

Polyethylene glycol and contrast-enhanced MRI of Crohn's disease in children: preliminary experience.

OBJECTIVE: To assess the ability of MRI to detect bowel abnormalities in children affected by Crohn's disease (CD). MATERIALS AND METHODS: We studied 22 children (age range 8-18 years) referred to us with a known history of CD. MRI was carried out using a 1.5-T unit with a maximum gradient field strength of 16 mT and a phased-array body coil. The sequences performed were breath-hold coronal and axial T2-weighted, express fat saturation, followed by T1-weighted, spoiled gradient, fast fat saturation after IV injection of gadolinium chelate (0.3 mmol/kg) for contrast enhancement of the bowel wall. Bowel distension was achieved using oral administration of isosmotic polyethylene glycol solution. Ileo-colonoscopy was considered the gold standard for evaluation of superficial abnormalities and stenoses of the colon and terminal ileum. MRI findings of bowel-wall thickening, increased vascularisation and extramural involvement were compared with the findings using B-mode and Doppler US. Concordance between MRI and endoscopy, B-mode US and Doppler US findings was determined by the Kappa statistical method. RESULTS: Superficial lesions were not shown by MRI. MR enteroclysis easily detected stenoses, thickening and hyperaemia of bowel wall. Concordance of findings between MRI and endoscopy was 90% (K=0.79, substantial concordance). Concordance of findings between MRI and US concerning bowel-wall thickening and increased vascularisation was 95% (K=0.875, excellent concordance) and 80% (K=0.6, fairly good concordance), respectively. CONCLUSIONS: Our initial results show that MRI can detect intra- and extra-mural lesions of CD. The high concordance observed between MRI, endoscopy, US and Doppler US findings suggests that MRI is at least comparable for diagnostic capability with these techniques offering, thanks to multiplanar projections, an improved visualisation of the bowel without ionising radiation.

Imaging of the normal and affected thyroid in children with emphasis on sonography.

In the past 15 years sonography (US) has become the most important imaging modality for the study of the thyroid gland. Thyroid pathologies are classifiable into congenital, diffuse and nodular diseases. US easily assesses congenital conditions such as agenesis or dysgenesis of the gland, although it may fail in demonstrating an ectopic gland. In diffuse diseases (Graves' disease and Hashimoto's disease) is a useful tool in assessing and subsequently monitoring the course of the disease. In thyroid nodular diseases, US main role is to localize nodules, to differentiate solid from cystic and partially cystic structures, and to look for other clinically unknown nodules in the gland. However it can be difficult to determine with US alone whether a nodule is benign or malignant.