Common disorders of synovium-lined joints: pathogenesis, imaging abnormalities, and complications

Activatable fluorescent probes for imaging and diagnosis of rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune disease that is primarily manifested as synovitis and polyarticular opacity and typically leads to serious joint damage and irreversible disability, thus adversely affecting locomotion ability and life quality. Consequently, good prognosis heavily relies on the early diagnosis and effective therapeutic monitoring of RA. Activatable fluorescent probes play vital roles in the detection and imaging of biomarkers for disease diagnosis and in vivo imaging. Herein, we review the fluorescent probes developed for the detection and imaging of RA biomarkers, namely reactive oxygen/nitrogen species (hypochlorous acid, peroxynitrite, hydroxyl radical, nitroxyl), pH, and cysteine, and address the related challenges and prospects to inspire the design of novel fluorescent probes and the improvement of their performance in RA studies.

Correlation between TM joint disease and rheumatic diseases detected on bone scintigraphy and clinical factors

The aim of this study was to evaluate the effect of rheumatic disease as a risk factor for temporomandibular disease (TMD). A total of 143 outpatients reporting symptoms indicating rheumatic disease at their first visit to the rheumatology clinic were included. We evaluated the temporomandibular joint (TMJ) with scintigraphic images, and standard questionnaires were administered for the symptomatic assessment for all patients. The patients were classified into ‘healthy controls’ or as per their diagnosis into ‘osteoarthritis’, ‘axial spondyloarthritis’, ‘peripheral spondyloarthritis’, ‘rheumatoid arthritis’, or ‘other rheumatic diseases’ groups. The patients were also differentiated depending on the presence or absence of axial involvement. The relation between the rheumatic disease type and findings at the TMJ were evaluated using statistical analyses. Axial spondyloarthritis, peripheral spondyloarthritis, and rheumatic arthritis patients showed significantly higher scintigraphic uptake at the TMJ compared with those in the control and osteoarthritis groups (axial spondyloarthritis: 4.5, peripheral spondyloarthritis: 4.5, rheumatoid arthritis: 4.09, control: 3.5, osteoarthritis: 3.4, p < 0.0001). Compared with patients without axial involvement, patients with axial involvement also showed significantly higher TMJ scintigraphic uptake (axial involvement: 4.24, without axial involvement: 3.50, p < 0.0001) with elevated symptomatic rates in TMD (axial involvement: 17.82, without axial involvement: 9.97, p < 0.005).

Oral and Subcutaneous Administration of a Near-Infrared Fluorescent Molecular Imaging Agent Detects Inflammation in a Mouse Model of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease that causes irreversible damage to the joints. However, effective drugs exist that can stop disease progression, leading to intense interest in early detection and treatment monitoring to improve patient outcomes. Imaging approaches have the potential for early detection, but current methods lack sensitivity and/or are time-consuming and expensive. We examined potential routes for self-administration of molecular imaging agents in the form of subcutaneous and oral delivery of an integrin binding near-infrared (NIR) fluorescent imaging agent in an animal model of RA with the long-term goal of increasing safety and patient compliance for screening. NIR imaging has relatively low cost, uses non-ionizing radiation, and provides minimally invasive spatial and molecular information. This proof-of-principle study shows significant uptake of an IRDye800CW agent in inflamed joints of a collagen antibody induced arthritis (CAIA) mouse model compared to healthy joints, irrespective of the method of administration. The imaging results were extrapolated to clinical depths in silico using a 3D COMSOL model of NIR fluorescence imaging in a human hand to examine imaging feasability. With target to background concentration ratios greater than 5.5, which are achieved in the mouse model, these probes have the potential to identify arthritic joints following oral delivery at clinically relevant depths.

Correlation between Focal Nodular Low Signal Changes in Hoffa's Fat Pad Adjacent to Anterior Femoral Cartilage and Focal Cartilage Defect Underlying This Region and Its Possible Implication

Purpose. This study investigates the association between focal nodular mass with low signal in Hoffa's fat pad adjacent to anterior femoral cartilage of the knee (FNMHF) and focal cartilage abnormality in this region. Method. The magnetic resonance fast imaging employing steady-state acquisition sequence (MR FIESTA) sagittal and axial images of the B1 and C1 region (described later) of 148 patients were independently evaluated by two reviewers and categorized into four categories: normal, FNMHF with underlying focal cartilage abnormality, FNMHF with normal cartilage, and cartilage abnormality with no FNMHF. Results. There was a significant association (p = 0.00) between FNMHF and immediate adjacent focal cartilage abnormality with high interobserver agreement. The absence of focal nodular lesions next to the anterior femoral cartilage has a very high negative predictive value for chondral injury (97.8%). Synovial biopsy of focal nodular lesion done during arthroscopy revealed some fibrocollagenous tissue and no inflammatory cells. Conclusion. We postulate that the FNMHF adjacent to the cartilage defects is a form of normal healing response to the cartilage damage. One patient with FHMHF and underlying cartilage abnormality was rescanned six months later. In this patient, the FNMHF disappeared and normal cartilage was observed in the adjacent region which may support this theory.

Accurate quantitative assessment of synovitis in rheumatoid arthritis using pixel-by-pixel, time-intensity curve shape analysis

OBJECTIVE

To improve on the reproducibility and sensitivity of the assessment of patients with rheumatoid arthritis (RA), two semi-automated measurement methods of the area of enhancing pannus (AEP), based on thresholding (AEP_THRES) and pixel-by-pixel time-intensity curve analysis (AEP_TIC), were evaluated as an alternative for the gold-standard manual contouring method (AEP_MANUAL).

METHODS

8 patients (7 females and 1 male) with RA of the wrist or finger joints participated in the study. A three-dimensional contrast-enhanced dynamic sequence was used at 3 T. After identifying the most relevant time-intensity curve (TIC) shape in terms of synovitis by comparing with the synovitis score using the RA-MRI scoring system, three different approaches for measuring the AEP were performed. Spearman's test of rank correlation was used to compare AEPs via two semi-automated methods (AEP_THRES and AEP_TIC) against manual segmentation (AEP_MANUAL) in the entire hand region as well as the wrist and the finger regions.

RESULTS

The TIC shape of "washout after fast initial enhancement" had excellent correlation with synovitis score (r = 0.809). The correlation coefficient between AEP_TIC and AEP_MANUAL was evaluated to be better than that of AEP_THRES and AEP_MANUAL in the wrist region (AEP_THRES: r = 0.716, AEP_TIC: r = 0.815), whereas these were of comparable accuracy for the entire hand and the finger regions.

CONCLUSION

This study suggests that TIC analysis may be an alternative to manual contouring for pannus quantification and provides important clinical information of the extent of the disease in patients with RA.

ADVANCES IN KNOWLEDGE

TIC shape analysis can be applied for new quantitative assessment for RA synovitis in the wrist.

Temporomandibular joint diagnostics using CBCT

The present review will give an update on temporomandibular joint (TMJ) imaging using CBCT. It will focus on diagnostic accuracy and the value of CBCT compared with other imaging modalities for the evaluation of TMJs in different categories of patients; osteoarthritis (OA), juvenile OA, rheumatoid arthritis and related joint diseases, juvenile idiopathic arthritis and other intra-articular conditions. Finally, sections on other aspects of CBCT research related to the TMJ, clinical decision-making and concluding remarks are added. CBCT has emerged as a cost- and dose-effective imaging modality for the diagnostic assessment of a variety of TMJ conditions. The imaging modality has been found to be superior to conventional radiographical examinations as well as MRI in assessment of the TMJ. However, it should be emphasized that the diagnostic information obtained is limited to the morphology of the osseous joint components, cortical bone integrity and subcortical bone destruction/production. For evaluation of soft-tissue abnormalities, MRI is mandatory. There is an obvious need for research on the impact of CBCT examinations on patient outcome.

Pit above the lesser tuberosity in axial view radiography

PURPOSE

This study examined the relationship between the presence of a pit above the lesser tuberosity on axial view radiographs and rotator cuff tears and compared the demographic data between groups according to the presence of a pit above the lesser tuberosity. The hypothesis of this study was that the radiographic finding of a pit above the lesser tuberosity is related to rotator cuff tears.

METHODS

For 112 patients with a symptomatic rotator cuff tear, plain radiographs of the symptomatic shoulder (tear side radiographs) and plain radiographs of the asymptomatic contralateral shoulder (no-tear side radiographs) were assessed. Seventeen radiological findings, including a pit above the lesser tuberosity, osteophytes, subchondral cysts, and sclerosis, were recorded by one blinded observer. Demographic data such as age, duration of symptoms, sex, arm dominance, smoking history, trauma history, American Shoulder and Elbow Surgeons score, Constant score, and involved tendon were collected.

RESULTS

A pit above the lesser tuberosity was noted on tear side radiographs of 40 patients (35.7 %) and on the no-tear side radiographs of 27 patients (24.1 %), representing a significant difference (P = 0.040). A pit associated with a rotator cuff tear was observed more often in the dominant arm (P = 0.040) and more often in patients with less previous trauma (P = 0.024).

CONCLUSIONS

A pit above the lesser tuberosity on axial view radiography was associated with a rotator cuff tear and occurred more often in the dominant arm of patients who had no trauma history.

LEVEL OF EVIDENCE

Prognostic study, Level III.

A case of pseudogout of the temporomandibular joint with giant cell reparative granuloma of the temporal bone

Pseudogout, also known as calcium pyrophosphate dihydrate deposition disease (CPPD) with giant cell reparative granuloma (GCRG) of the temporal bone is a rare disease, which is very easy to misdiagnose. When two diseases occur simultaneously, the pathological tissue of diseases is closely associated, which complicates clinical representation and causes enormous difficulty in diagnosis and treatment. We report a case of CPPD of the temporomandibular joint accompanied by surrounding GCRG of temporal bone in a 62-year-old male.

Cysts within and adjacent to the lesser tuberosity: correlation with shoulder arthroscopy

OBJECTIVE

The purpose of our study was to determine if cysts in and adjacent to the lesser tuberosity are associated with rotator cuff pathology found at arthroscopy.

MATERIALS AND METHODS

A retrospective review was undertaken of the magnetic resonance (MR) imaging of 286 consecutive arthroscopic procedures performed by a single orthopedic shoulder surgeon from February 2001 to June 2009. Images of the shoulders were reviewed by an experienced fellowship-trained musculoskeletal radiologist, reader 1, and a musculoskeletal fellow, reader 2, for the presence and location of lesser tuberosity cysts. Cysts were grouped by their location into those within the lesser tuberosity and those adjacent to the lesser tuberosity. Interreader agreement was calculated using kappa values.

RESULTS

A total of 26 patients (17 men, 9 women; age range 14–84 years; mean of 61 years) had cysts in or adjacent to the lesser tuberosity. For reader 1, patients with cysts located in the lesser tuberosity were found to be significantly older(p=00.03) and more likely to have subscapularis tendon tears(p=00.02) than patients with cysts located adjacent to the tuberosity. No significant difference in any category between patients with a cyst located in the lesser tuberosity and those adjacent to the tuberosity was identified for reader 2. Interreader agreement of imaging findings ranged from fair to near perfect agreement.

CONCLUSION

Cysts located in the lesser tuberosity at the insertion of the subscapularis tendon are suggestive of subscapularis tendon pathology and may occur in older individuals.

[Imaging of temporo-mandibular disorders]

Dominated for years by standard films (tomographic mouth open and mouth closed X-rays, MRI) radiographs of the TMJ have progressively lost their usefulness to diagnosticians who have progressively increased their reliance on well codified clinical examinations, which suffice in a great majority of cases.The indications for and diagnostic worth of radiological studies and the impact they have on the management of TMJ disorders are today quite low especially when the high cost of procedures like MRI, computerized tomography, and CBCT is taken into account. In this article we discuss the various maladies that dentists might encounter and the situations in which radiological examinations are still indicated.

Correlative BOLD MR imaging of stages of synovitis in a rabbit model of antigen-induced arthritis

BACKGROUND

Because of the ability of blood-oxygen-level-dependent (BOLD) MRI to assess blood oxygenation changes within the microvasculature, this technique holds potential for evaluating early perisynovial changes in inflammatory arthritis.

OBJECTIVE

To evaluate the feasibility of BOLD MRI to detect interval perisynovial changes in knees of rabbits with inflammatory arthritis.

MATERIALS AND METHODS

Rabbit knees were injected with albumin (n=9) or saline (n=6) intra-articularly, or were not injected (control knees, n=9). Except for two rabbits (albumin-injected, n=2 knees; saline-injected, n=2 knees) that unexpectedly died on days 7 and 21 of the experiment, respectively, all other animals were scanned with BOLD MRI on days 0, 1, 7, 14, 21 and 28 after induction of arthritis. T2*-weighted gradient-echo MRI was performed during alternate 30 s of normoxia/hyperoxia. BOLD MRI measurements were compared with clinical, laboratory and histological markers.

RESULTS

Percentage of activated voxels was significantly greater in albumin-injected knees than in contralateral saline-injected knees (P=0.04). For albumin-injected knees (P<0.05) and among different categories of knees (P=0.009), the percentage of activated BOLD voxels varied over time. A quadratic curve for on-and-off BOLD difference was delineated for albumin- and saline-injected knees over time (albumin-injected, P=0.047; saline-injected, P=0.009). A trend toward a significant difference in synovial histological scores between albumin-injected and saline-injected knees was noted only for acute scores (P=0.07).

CONCLUSION

As a proof of concept, BOLD MRI can depict perisynovial changes during progression of experimental arthritis.

Reliability and convergent validity of different BOLD MRI frameworks for data acquisition in experimental arthritis

RATIONALE AND OBJECTIVES

The clinimetric properties of blood oxygen level‒dependent (BOLD) magnetic resonance imaging (MRI) for assessment of musculoskeletal changes have been poorly investigated. The study objectives were to assess the interframework reliability of data acquisition of BOLD MRI and to test its convergent validity in chronic arthritis in a rabbit model of inflammatory arthritis as compared with corresponding clinical and laboratory measures.

MATERIALS AND METHODS

One of the knees of 12 New Zealand male white rabbits was injected with a 1% carrageenin solution, and the contralateral (control) one was not. Twelve rabbits were euthanized on day 28 of arthritis (chronic arthritis). Clinical (joint diameters), laboratory (serum amyloid A concentration), and BOLD MRI measurements were obtained on days 0, 1, and 28 of arthritis. Twenty paradigms of data acquisition and analysis were applied.

RESULTS

The most reliable MRI parameters set, regardless of threshold values used for data analysis, was spiral technique (level 1), 40 ms of echo time (level 2), 60 seconds of on_ and off_ paradigm (level 3) and carbogen mixture of gases (95% O2 + 5% CO2) (level 4). With regard to construct validity, BOLD imaging correlated moderately (r = -.54, P < .0001) with knee diameters, and weakly (r = -.35, P = .01) with laboratory indices (high threshold for analysis).

CONCLUSION

BOLD MRI has a substantial or excellent interframework reliability for assessment of arthritic rabbit knees; however, it correlates only moderately or poorly with clinical and laboratory measures. Nevertheless, this study supports further validation of BOLD MRI for assessment of soft tissue changes in a rabbit model of arthritis.

MRI in juvenile idiopathic arthritis and juvenile dermatomyositis

The use of MRI in the assessment of the musculoskeletal system in children has important differences from its use in adults. Growth in children has significant impact on the epiphysis and growth plate, which are important structures in the growing child, and there are radiological features that differ from those in adults: disease may alter structures during a period of growth; the pathologies themselves are a distinct group of diseases at variance with adult arthritis and myositis, with a different spectrum of differential diagnoses; and many technical issues are different when imaging a child. These are important considerations in choosing the appropriate imaging. MRI is a powerful and valuable imaging technique in pediatric musculoskeletal pathologies, with considerable potential for future developments to enhance its role in diagnosis, management, and therapeutic intervention for these children.

Nutritional considerations in joint health

Osteoarthritis, a debilitating joint disorder, is the most common form of arthritis in the United States, where it affects an estimated 21 million people. In 2004, the direct and indirect health care costs associated with all forms of arthritis were approximately 86 billion dollars. Joint discomfort from osteoarthritis and other joint disorders may reduce physical activity in individuals experiencing this condition, resulting in energy imbalance and weight gain. Increased weight can exacerbate existing problems, as additional stress on joints stimulates risk of additional joint disorders. Dietitians play a role in preventing or reversing the problem of joint disorders by promoting nutrient-rich diets that support joint health through improvement in cartilage metabolism. In addition, counseling individuals on weight management and active lifestyles are key strategies for the management of joint health.

Bildgebende Verfahren in der Frühdiagnostik rheumatischer Veränderungen der Hände

PURPOSE

Besides the use of conventional x-rays in the diagnostic work-up of initial changes in patients suffering from rheumatoid arthritis (RA), 3-phase bone scintigraphy (3P-Sz) is as well established as magnetic resonance imaging (MRI). The aim of this study was to compare the diagnostic value of ultrasound of the hands with proven methods such as conventional x-rays, low-field MRI and 3P-Sz.

METHODS

A total of 30 patients were studied using a 1 day protocol with ultrasound, 3P-Sz, MRI and x-ray of the hands. Images were visually assessed by two blinded nuclear medicine physicians and radiologists and classified as RA typical and non-RA typical changes. All methods were compared to the summarized findings interpreted by a rheumatologist after 2 years.

RESULTS

Of the 30 patients, 19 presented with clinical symptoms of initial changes due to rheumatoid arthritis. Ultrasound revealed 14/19 patients with the correct diagnosis. Conventional x-rays indicated 11/19 patients, while 3P-Sz (100%) and low-field MRI (95%) showed high sensitivity. It was possible to differentiate between inflammation and inconspicuous findings.

CONCLUSIONS

An experienced examiner can use ultrasound effectively for the initial diagnosis of RA. Based on its low cost, ultrasound is a valid alternative to conventional x-rays.

Imaging of juvenile idiopathic arthritis

Over the past decade there have been considerable changes in the classification and imaging of juvenile idiopathic arthritis (JIA). Radiology now has a considerable role in the management of JIA, the differential diagnosis, monitoring disease progression and detecting complications. The different imaging modalities available, their role and limitations are discussed in this article and the various disease features that the radiologist should be aware of are described. An approach to the imaging of the child with joint disease and in the monitoring of disease complications are also discussed.

[Reactive synovitis: MRI features with arthroscopic correlation]

OBJECTIVES

To evaluate MR imaging in detecting and characterizing secondary reactive synovitis and correlate the results with arthroscopy.

MATERIALS AND METHODS

Retrospective study of 10 patients referred for MR imaging and arthroscopy of the knee or shoulder. The diagnosis of reactive synovitis was confirmed by arthroscopy and pathological examination. Synovial thickening was graded at MRI as follows. Grade 0: normal; grade 1: diffuse synovial thickening; grade 2: nodular synovial hypertrophy; grade 3: pseudotumoral synovial mass.

RESULTS

Synovitis was described at MRI in 8 cases. There were 2 false negative results on MR imaging for the knee. Synovitis was secondary to knee trauma and rotator cuff tear or surgery of the shoulder. On arthroscopy, all synovial lesions were detected and confirmed at pathology. Synovitis was not detected at MRI (grade 0) in 20% of cases. Synovitis appeared diffuse (grade 1) in 30%, nodular (grade 2) in 30% and pseudotumoral (grade 3) in 20%. Bony erosions were adjacent to synovial thickening in 5 cases.

CONCLUSION

Reactive synovitis can occur after trauma. MR imaging is useful in detecting and evaluating secondary reactive synovitis. Arthroscopy and synovial biopsy are necessary to exclude infectious or tumoral synovitis.

Role of Magnetic Resonance Imaging in the Clinical Diagnosis of the Temporomandibular Joint

Temporomandibular joint (TMJ) abnormalities cannot be reliably assessed by a clinical examination. Magnetic resonance imaging (MRI) may depict joint abnormalities not seen with any other imaging method and thus is the best method to make a diagnostic assessment of the TMJ status. In patients with temporomandibular joint disorder (TMD) referred for diagnostic imaging the predominant TMJ finding is internal derangement related to disc displacement. This finding is significantly more frequent than in asymptomatic volunteers, and occurs in up to 80% of patients consecutively referred for TMJ imaging. Moreover, certain types of disc displacement seem to occur almost exclusively in TMD patients, namely complete disc displacements that do not reduce on mouth opening. Other intra-articular abnormalities may additionally be associated with the disc displacement, predominantly joint effusion (which means more fluid than seen in any asymptomatic volunteer) and mandibular condyle marrow abnormalities (which are not seen in volunteers). These conditions seem to be closely related. Nearly 15% of TMD patients consecutively referred for TMJ MRI will have joint effusion, of whom about 30% will show bone marrow abnormalities. In a surgically selected material of joints with histologically documented bone marrow abnormalities nearly 40% showed joint effusion. Disc displacement is mostly bilateral, but joint effusion seems to be unilateral or with a lesser amount of fluid in the contralateral joint. Abnormal bone marrow is also mostly unilateral. Many patients have unilateral pain or more pain on one side. In a regression analysis the self-reported in-patient TMJ pain side difference was positively dependent on TMJ effusion and condyle marrow abnormalities, but negatively dependent on cortical bone abnormalities. Of the joints with effusion only one fourth showed osteoarthritis. Thus, there seems to be a subgroup of TMD patients showing more severe intra-articular pathology than disc displacement alone, and mostly without osteoarthritis. It should, however, be emphasized that patients with TMJ effusion and/or abnormal bone marrow in the mandibular condyle seem to constitute only a minor portion (less than one fourth) of consecutive TMD patients referred for diagnostic TMJ imaging. The majority of patients have internal derangement related to disc displacement, but without accompanying joint abnormalities. In patients with rheumatoid arthritis and other arthritides TMJ involvement may mimick the more common TMDs. Using MRI it is possible, in most cases, to distinguish these patients from those without synovial proliferation.

Reactive Carpal Synovitis: Initial Experience with MR Imaging

PURPOSE

To retrospectively evaluate the accuracy of various magnetic resonance (MR) imaging findings in the diagnosis of reactive carpal synovitis.

MATERIALS AND METHODS

Institutional review board approval was obtained, and the need for informed consent was waived. This study was compliant with the Health Insurance Portability and Accountability Act. Thirty-five consecutive patients (19 male and 16 female patients; age range, 13-57 years) who underwent arthroscopy and MR imaging within 4 weeks of surgery were evaluated by two reviewers for the following potential findings of synovitis: (a) distention of the pisotriquetral recess by fluid, (b) distention of the radial and/or prestyloid recess, (c) synovial enhancement (in patients who received contrast material), (d) amount of dorsal capsule distention, and (e) the location of bone marrow edema, if any. The chi2 and paired t tests were used to assess these findings in patients with and patients without arthroscopically proved synovitis. The sensitivity, specificity, positive and negative predictive values, and accuracy of these findings in the detection of synovitis were calculated.

RESULTS

Fluid in the pisotriquetral recess was seen in nine of the 14 patients with synovitis and five of the 21 patients without synovitis (P = .018). Distention of the radial and/or prestyloid recess was observed in six of the 14 patients with synovitis and two of the 21 patients without synovitis (P = .027). Among the 24 patients who received contrast material, synovial enhancement was seen in seven of eight patients with synovitis and three of 16 patients without synovitis (P = .002). The dorsal capsule measured 1-7 mm (mean, 3.07 mm) in the 14 patients with synovitis and 2-7 mm (mean, 3.76 mm) in the 21 patients without synovitis (P = .193). Although bone marrow edema was seen globally in similar frequencies (nine of 14 patients with synovitis, nine of 21 patients without synovitis), pisotriquetral bone marrow edema was seen only in patients with synovitis (two of nine patients).

CONCLUSION

Fluid in the pisotriquetral recess, enhancing synovium, and, less commonly, pisotriquetral bone marrow edema are MR imaging findings that may help in the diagnosis of reactive carpal synovitis.

Ultrasound and power Doppler evaluation of the hand and wrist in patients with psoriatic arthritis

PURPOSE

To evaluate the ability of high-resolution and power Doppler sonography in detecting joint and tendon abnormalities in patients with psoriatic arthritis (PsA) of the hands and wrists compared with clinical and radiological findings.

MATERIAL AND METHODS

Thirty-six patients with psoriatic arthritis of the hands and wrists and 10 healthy controls were examined with ultrasound (US). The degree of synovial proliferation, tenosynovitis, presence of joint effusion as well as the vascularity of synovial tissue was estimated. US findings were scored using a newly devised scoring system.

RESULTS

Thirty-two patients had articular synovial proliferation and/or tenosynovitis/ tendinitis or joint effusion in one or more joints according to US. Twenty-two patients had tendon changes; only five had joint effusion. The synovial, Doppler, and total articular-teno scores were all significantly correlated to the number of swollen joints. The scores, however, did not correlate to other clinical or laboratory measurements of disease activity.

CONCLUSION

US proved effective in demonstrating PsA involvement of the hands and wrists and was more sensitive than clinical examination in detecting pathology. Long-term follow-up studies are needed to evaluate whether this can change the traditional approach for assessing involvement of joints and tendons in PsA.

Estimation of inflammation by Doppler ultrasound: quantitative changes after intra-articular treatment in rheumatoid arthritis

OBJECTIVE

To evaluate the use of ultrasound, including quantitative Doppler analysis of synovial vascularisation, before and after intra-articular treatment with glucocorticosteroids in patients with rheumatoid arthritis (RA).

METHODS

51 patients with RA were followed prospectively after an intra-articular glucocorticosteroid injection. Disease modifying antirheumatic drug treatment was kept unchanged and no further injections given in this observation period. At baseline, disease activity was estimated clinically by target join pain on a 100 mm visual analogue scale, on which the target joint was scored 0-3 for swelling and tenderness, and by ultrasound measurements of grey scale pixels, colour Doppler pixels, and the spectral Doppler resistive index (RI) as indicators of synovial swelling and inflammation. After four weeks, the measurements were repeated on the same joint. An observer unaware of the sequence and patient number evaluated the ultrasound images.

RESULTS

At one month follow up after the glucocorticosteroid injection, a marked decrease in the fraction of colour pixels was seen in 41/51 patients (Student's t test p<0.001). Correspondingly, the RI increased indicating a diminished flow to the synovium (Student's t test p<0.01). Both the fraction of colour pixels and the RI values corresponded with the clinical evaluation and with the subjective effect of the treatment. The synovial membrane volume estimated by total amount of pixels showed a significant decrease by 31% after treatment.

CONCLUSION

Ultrasound-Doppler seems to be a promising tool for the estimation of synovial activity in arthritis. After intra-articular glucocorticosteroid, changes in RI and fraction of colour pixels may both be used as quantitative measurements of the blood flow.

Doppler ultrasound and magnetic resonance imaging of synovial inflammation of the hand in rheumatoid arthritis: a comparative study

OBJECTIVE

To compare the quantitative and qualitative information obtained by Doppler ultrasound (US) measurements of the wrist joints and the small joints of the hand with the information obtained by postcontrast magnetic resonance imaging (MRI) and to correlate the imaging results with clinical observations in patients with rheumatoid arthritis (RA).

METHODS

Twenty-nine consecutive RA patients were studied; 196 joints (29 wrist and 167 finger joints) were examined by both US and MRI. Parameters of inflammation were the color fraction and the resistance index (RI) obtained with color Doppler US and the thickness of enhanced synovium (in mm) and the MRI score obtained with postcontrast MRI. Clinical examination and measurements of the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level were performed on the same day as the imaging studies.

RESULTS

There was a highly significant association between US indices of inflammation and postcontrast MRI scores. The mean values for both the color fraction and the RI were significantly different in the group without joint swelling compared with the other groups. The mean RI values were significantly different in the group without joint tenderness compared with the other groups. The mean thickness of enhanced synovium on postcontrast MRI was significantly different between the group without joint swelling and the other groups, but this difference was statistically significant only for the comparison of the group without joint tenderness versus the group with maximum tenderness. No association between the MRI or US estimates of inflammation and values on the visual analog scale for pain, Health Assessment Questionnaire, duration of morning stiffness, ESR, or CRP was found.

CONCLUSION

Estimates of synovial inflammatory activity by Doppler US and postcontrast MRI were comparable. Estimation of synovial inflammatory activity by the RI and color fraction parameters of US appears to be a promising method of detecting and monitoring inflammatory activity in patients with RA.

Metacarpophalangeal joints in rheumatoid arthritis: laser Doppler imaging--initial experience

Laser Doppler imaging is a noninvasive method yielding a spatial perfusion map. With use of a near-infrared laser, elevated perfusion associated with the metacarpophalangeal joints was detectable in patients with active rheumatoid arthritis. Findings at laser Doppler imaging correlated with pain scores and synovitis detected at ultrasonography, whereas the power Doppler sign (red pixels inside the active green box) did not. Laser Doppler imaging has the potential to help assess soft-tissue inflammation.

Ultrasound versus MRI in the evaluation of juvenile idiopathic arthritis of the knee

OBJECTIVE

To examine the role of ultrasound versus magnetic resonance imaging (MRI) in assessing joint inflammation in patients with juvenile idiopathic arthritis (JIA) of the knee.

METHODS

This study was conducted on 38 patients with juvenile idiopathic arthritis (25 girls and 13 boys), whose ages ranged between 2-17 years (mean 8 years), presenting with joint swelling, tenderness, pain on motion and/or limitation of movement. Plain radiography, high-resolution ultrasound and MRI examinations of the knee (before and after contrast administration) were made on all patients. A control group of ten subjects was also examined.

RESULTS

Compared to the control group, sonographic examination was found to be of great value as regards the joint effusion, popliteal cysts, lymph nodes and to a lesser extent, the degree of affection of the articular cartilage. MRI was superior in evaluating the extent of synovial proliferation (pannus), thinning out and erosions of articular cartilage, loculated effusions as well as hypoplastic menisci and ligaments, especially after contrast enhancement.

CONCLUSION

Ultrasound is a simple, inexpensive and valuable tool in evaluating the initial stages of JIA. In more advanced stages of JIA and also for monitoring the progression of the disease process and response to therapy, MRI examination following gadolinium proved to be superior in evaluation of the joint affection.

MRI and ultrasound in children with juvenile chronic arthritis

In this era of advancing imaging technology, a knowledge of the relative values of available imaging techniques is necessary to optimize the management of children with juvenile chronic arthritis (JCA). After clinical examination, plain films remain the initial investigation. The need for radiation protection must be a priority in children with JCA. Conventional radiographs allow grouping of the various arthritides (on the base of the distribution and pattern of joint space changes) and staging of disease progression. Ultrasound (US) is very sensitive in the detection of joint effusions, especially in the hip, and guides fluid aspiration. US and Doppler can be used for the evaluation of synovial hypertrophy and activity. Arthrography and to a certain extent nuclear studies have been replaced by magnetic resonance imaging (MRI). MRI can demonstrate articular cartilage, joint effusion, synovial hypertrophy, cortical and medullary bone, cartilage and bone perfusion, and fibrocartilaginous structures (menisci and ligaments). Contrast enhanced MRI is the most sensitive modality to determine whether an arthritic condition is present. However, it does not assist in establishing a specific diagnosis. MRI determines accurately the activity and the extent of the disease and is particularly useful in the early detection of articular damage. Finally, MRI is of major importance in the evaluation of response to local therapy (especially steroids) and the detection of complications.

Arthritis of the finger joints: a comprehensive approach comparing conventional radiography, scintigraphy, ultrasound, and contrast-enhanced magnetic resonance imaging

OBJECTIVE

A prospective study was performed comparing conventional radiography, 3-phase bone scintigraphy, ultrasound, and magnetic resonance imaging (MRI) with precontrast and dynamic postcontrast examinations in 60 patients with various forms of arthritis including rheumatoid arthritis (RA), spondyl-arthropathy, and arthritis associated with connective tissue disease.

METHODS

A total of 840 finger joints were examined clinically and by all 4 imaging methods. Experienced investigators blinded to the clinical findings and diagnoses analyzed all methods independently of each other. The patients were divided into 2 groups. Group 1 included 32 patients (448 finger joints) without radiologic signs of destructive arthritis (Larsen grades 0-1) of the evaluated hand and wrist and group 2 included 28 patients (392 finger joints) with radiographs revealing erosions (Larsen grade 2) of the evaluated hand and/or wrist.

RESULTS

Clinical evaluation, scintigraphy, MRI, and ultrasound were each more sensitive than conventional radiography in detecting inflammatory soft tissue lesions as well as destructive joint processes in arthritis patients in group 1. All differences were statistically significant. We found ultrasound to be even more sensitive than MRI in the detection of synovitis. MRI detected erosions in 92 finger joints (20%; 26 patients) in group 1 that had not been detected by conventional radiography.

CONCLUSION

Our data indicate that MRI and ultrasound are valuable diagnostic methods in patients with arthritis who have normal findings on radiologic evaluation.

Arthritis of the finger joints: a comprehensive approach comparing conventional radiography, scintigraphy, ultrasound, and contrast-enhanced magnetic resonance imaging

OBJECTIVE

A prospective study was performed comparing conventional radiography, 3-phase bone scintigraphy, ultrasound, and magnetic resonance imaging (MRI) with precontrast and dynamic postcontrast examinations in 60 patients with various forms of arthritis including rheumatoid arthritis (RA), spondyl-arthropathy, and arthritis associated with connective tissue disease.

METHODS

A total of 840 finger joints were examined clinically and by all 4 imaging methods. Experienced investigators blinded to the clinical findings and diagnoses analyzed all methods independently of each other. The patients were divided into 2 groups. Group 1 included 32 patients (448 finger joints) without radiologic signs of destructive arthritis (Larsen grades 0-1) of the evaluated hand and wrist and group 2 included 28 patients (392 finger joints) with radiographs revealing erosions (Larsen grade 2) of the evaluated hand and/or wrist.

RESULTS

Clinical evaluation, scintigraphy, MRI, and ultrasound were each more sensitive than conventional radiography in detecting inflammatory soft tissue lesions as well as destructive joint processes in arthritis patients in group 1. All differences were statistically significant. We found ultrasound to be even more sensitive than MRI in the detection of synovitis. MRI detected erosions in 92 finger joints (20%; 26 patients) in group 1 that had not been detected by conventional radiography.

CONCLUSION

Our data indicate that MRI and ultrasound are valuable diagnostic methods in patients with arthritis who have normal findings on radiologic evaluation.

Magnetic resonance imaging-determined synovial membrane and joint effusion volumes in rheumatoid arthritis and osteoarthritis: comparison with the macroscopic and microscopic appearance of the synovium

OBJECTIVE

To evaluate the relationship between synovial membrane and joint effusion volumes determined by magnetic resonance imaging (MRI) and macroscopic and microscopic synovial pathologic findings in patients with rheumatoid arthritis (RA) and osteoarthritis (OA).

METHODS

Synovial biopsies were performed, and macroscopic grades of synovitis assigned, at preselected knee sites during arthroscopy or arthrotomy in 17 knees with RA and 25 with OA. Synovial inflammation and 9 separate tissue characteristics were graded histologically. Synovial membrane and joint effusion volumes were determined by preoperative MRI, enhanced with intravenous gadopentetate dimeglumine.

RESULTS

MRI-determined synovial membrane volumes were correlated with the overall histologic assessment of synovial inflammation (Spearman's sigma = 0.55, P < 0.001), with fibrin deposition, with subsynovial mononuclear and polymorphonuclear leukocyte infiltration (sigma = 0.51-0.59), and less significantly with macroscopic synovitis, vessel proliferation, and granulation tissue formation (sigma = 0.40-0.42). No correlation with synovial lining multiplication, perivascular edema, villous formation, or fibrosis was found (sigma < 0.30).

CONCLUSION

MRI-determined synovial volumes are correlated with synovial inflammatory activity. Synovial volumes probably mainly reflect the mass of cell-infiltrated, vascularized subsynovial tissue, but may also be influenced by the cumulative synovial proliferative activity. MRI-determined synovial membrane and effusion volumes may be sensitive markers and/or predictors of disease activity and treatment outcome in RA.

Hypertrophic bursopathy of the subacromial-subdeltoid bursa in juvenile rheumatoid arthritis: sonographic appearance

Hypertrophic bursopathy is a term used to describe the massive synovial proliferation occasionally seen in the bursae of patients with arthritis. Involvement of the subacromial-subdeltoid (SA-SD) bursa in adults in uncommon, and it is still rarer in children. It may simulate synovial proliferation or fluid within the adjacent shoulder joint. Sonography clearly shows the location and nature of the soft-tissue swelling. Two cases of this entity in children with juvenile rheumatoid arthritis are described, one with a uniquely severe sonographic picture.

Current trends in temporomandibular joint imaging

Diagnostic imaging of the temporomandibular joint has undergone a revolutionary development during the last two decades. With advanced modalities we have been able to differentiate between different articular entities in patients with temporomandibular joint disorders. The purpose of this article is to review and discuss these modalities and their contribution to our present knowledge, with emphasis made on current trends in diagnostic temporomandibular joint imaging. The main section deals with diagnostic imaging of the subgroup of disorders with internal derangement caused by disk displacement including posttreatment imaging. Imaging of pathologic entities characterized by chronic inflammation such as rheumatoid arthritis are discussed in the second section. Finally, the potential of diagnostic imaging of infrequent conditions such as tumors is briefly reviewed. Magnetic resonance imaging has surpassed arthrography and computed tomography for the evaluation of most patients in these three subgroups. In patients who have various forms of disk displacements with or without accompanying bone abnormalities, a diagnostic accuracy of at least 90% may be achieved by oblique sagittal and coronal magnetic resonance imaging. In addition, alterations in the condylar marrow may be detected. T2-weighted magnetic resonance imaging can make a significant diagnostic contribution by demonstrating inflammatory reactions such as joint effusion and marrow edema. In the subgroup of patients with chronic inflammatory diseases, magnetic resonance imaging may also demonstrate abnormalities not shown with other imaging modalities. Disk deformation, fragmentation, and destruction may indirectly suggest the presence of synovial proliferation/pannus formation, which in selected cases may be directly depicted with intravenous gadopentetate dimeglumine. For more detailed evaluation of the bone condition and of soft tissue calcifications in joints with inflammatory diseases, tumors, or other disorders, computed tomography is the preferable imaging modality.

Juvenile spondyloarthropathies: clinical manifestations and medical imaging

The spondyloarthropathies comprise four distinct entities--ankylosing spondylitis, psoriatic arthritis, the arthritis associated with inflammatory bowel disease, and Reiter's syndrome and other related forms of reactive arthritis. Although these are distinct diseases, they have a number of clinical, radiologic, and genetic characteristics in common which permit them to be classified under the unifying term "spondyloarthropathy". They are diseases of young adults, and when they present in patients under 16 years of age we refer to them as the "juvenile" spondyloarthropathies. They must be distinguished from juvenile rheumatoid arthritis, which is a totally separate entity; however the distinction may not always be obvious. Involvement of peripheral and sacroiliac joints commonly occurs in the juvenile spondyloarthropathies. The peripheral arthritis may be erosive and associated with bone apposition at the joint margins. Axial involvement is usually a late finding. Dactylitis and tenosynovitis are frequently present early on. Enthesitis, a highly specific feature, occurs much more often in the juvenile spondyloarthropathies than in the adult forms and it may be the only presenting feature. The plain radiograph is the primary and most important imaging modality for the assessment of these diseases. However, an expanding role of magnetic resonance imaging is evident.

Effect of intraarticular osmic acid on synovial membrane volume and inflammation, determined by magnetic resonance imaging

The changes in MR-determined synovial membrane volume, early synovial enhancement, and cartilage and bone erosions after osmic acid knee synovectomy were studied. Gadolinium-DTPA enhanced magnetic resonance imaging (MRI) of 18 knees with persistent arthritis was performed before and 1 month after treatment. The synovial membrane volume was significantly reduced (median -52%) in all 9 patients brought into clinical remission (p < 0.01), while no significant change was found in patients with clinical relapse. The early synovial enhancement was not significantly changed. MRI revealed progressive erosive changes in 2 patients. The time of relapse was correlated to a MR-erosion score, but not to early synovial enhancement or volumes of synovium or effusion (Spearman tests). MRI-determined synovial membrane volumes and early synovial enhancement may be objective quantitative markers of inflammation. MR-scores of cartilage and bone erosions are sensitive to progressive changes occurring within a month.

Radiologic case study. MRI in the diagnosis of synovial disease

Fourteen patients with various synovial diseases were imaged using conventional radiographic techniques and MRI. We had five patients with synovial tumors, including two each with PVNS and synovial osteochondromatosis. We had five patients with infections and four patients with various other forms of arthritis. Although MRI was found to be a useful means to visualize the synovium, the findings were nonspecific except in the case of PVNS.

Imaging temporomandibular joint abnormalities in patients with rheumatic disease. Comparison with surgical observations

The preoperative examination findings in the soft tissue and bone of 22 temporomandibular joints of 15 patients with rheumatic disease were compared with the diagnosis after TMJ surgery. Agreement was found in 15 joints with rheumatic involvement and in 4 with internal derangement. In 5 (with unsuccessful arthrotomography) of the 15 rheumatic joints, magnetic resonance imaging showed destruction of disks with soft-tissue replacement, corresponding to fibrous tissue/ankylosis observed at surgery. Bony fusions in 2 of these joints were depicted with computed tomography. In the remaining 10 joints, arthrotomography showed irregularly outlined small compartments corresponding to synovial proliferations observed during surgery. Similar arthrotomographic interpretation, however, was made in 2 of 3 temporomandibular joints with imaging-surgery disagreement; surgery showed fibrous adhesions. In the third joint with unsuccessful arthrotomography, magnetic resonance imaging showed internal derangement but no synovial proliferations that were surgically observed. As experienced with other joints, synovial proliferations (or fibrous adhesions) could not be depicted with magnetic resonance imaging. Thus, differentiation between internal derangement with and without rheumatic involvement could be impossible with both arthrotomography and unenhanced magnetic resonance imaging.