Differential diagnosis of rheumatoid and psoriatic arthritis at an early stage in the small hand and foot joints using magnetic resonance imaging.

The 2 major and clinically most important primary inflammatory rheumatic diseases which affect small hand and feet joints are rheumatoid arthritis (RA) and psoriatic arthritis (PsA). The most important initial histopathological feature of RA is synovitis followed by chronic proliferative granulomatous pannus-tissue, which is associated with cartilage and bone destruction. Early inflammatory changes in RA also develop synchronously within the subchondral bone marrow. Enthesitis is the hallmark of SNSA, and is often seen as one of the first radiological manifestations of the diseases. As a rule inflammation within the synovial joints, histologically similar to RA, is not so pronounced. Consequently destructive changes within the synovial joints are much less with the exception of PsA in which pronounced bone destruction may develop (arthritis mutilans). Considerable overlapping in clinical and morphological manifestation of RA and PsA may be present. For evaluation of hand and feet joints and surrounding soft tissue structures in RA and PsA different imaging modalities are used, which include projection radiography, ultrasonography (US), radionuclide techniques and magnetic resonance imaging (MRI). MRI has become the imaging modality of choice for evaluation of arthritis, when conventional radiography is not conclusive.

Quantification of synovitis in the cranio-cervical region: dynamic contrast enhanced and diffusion weighted magnetic resonance imaging in early rheumatoid arthritis--a feasibility follow up study.

OBJECTIVE: To test the feasibility of dynamic contrast enhanced (DCEI) and diffusion weighted (DWI) magnetic resonance imaging (MRI) for quantifying synovitis of the cranio-cervical (C-C) region in patients with early rheumatoid arthritis (RA) and neck pain at the beginning and at a six month follow up. METHODS: 27 patients with duration of RA of less than 24 months and neck pain were studied with standard qualitative MRI evaluation and two quantitative MRI methods (DCEI and DWI) at the level of atlantoaxial joints. Rate of early enhancement (REE), enhancement gradient (Genh) and apparent diffusion coefficient (ADC) were extracted from DCEI and DWI data. MRI was coupled with clinical assessment and radiographic imaging. RESULTS: Using standard qualitative MRI evaluation, unequivocal active synovitis (grade 2 or 3 contrast enhancement) was proved in 16 (59%) patients at baseline and 14 (54%) at follow up. DCEI and DWI measurements confirmed active synovitis in 25 (93%) patients at baseline and 24 (92%) at follow up. Average REE, Genh and ADC values decreased during follow up, however the difference was not statistically significant (p>0.05). Both qualitative and quantitative MRI methods confirmed active inflammatory disease in the C-C region following therapy although all clinical criteria showed signs of improvement of the peripheral disease. CONCLUSIONS: The study proved the feasibility of DCEI and DWI MRI for quantifying synovitis of the C-C region in patients with early RA and neck pain. Both techniques can be used as additional method for evaluation of synovitis of the C-C region in RA.

Risk of deterministic effects during endovascular aortic stent graft implantation.

Since the 1990s, stent graft implantation for aortic pathology has become an alternative to extensive surgical procedures in some patients. Indeed, many patients with such pathology are now treated endovascularly. Only limited data concerning the risk of a deterministic effect during aortic stent graft implantation are available Accordingly, 179 consecutive patients treated in our institute between October 2002 and July 2008 with endovascular aortic stent grafts were included in this study. Dosimetric data (kerma area product (KAP) and cumulative dose at the interventional reference point (CD(irp))) from radiograph reports were analysed for 172 patients. On a group of 19 patients, GAFCHROMIC XR type dosimetric films were also used to verify the automatic measurements. Readings from the integrated KAP meter were found to be too high and were therefore corrected - KAP to dose area product (DAP) and CD(irp) to entrance skin dose (ESD). Median DAP was 153 Gy cm² (35-700 Gy cm²) and median ESD was 0.44 Gy (0.12-2.73 Gy). Recorded dosimetric quantities were found to be good predictors of the skin dose and highlighted 4 patients (2.3%) who received skin doses that might cause possible deterministic effects. Endovascular stent graft implantation is less invasive than a surgical procedure and is widely used; mid-term results are encouraging. In a small number of patients, deterministic effects can occur even in departments with well-trained staff. Operators should inform the patients of possible skin injury after receiving high doses of ionising radiation and proper support must be available should that occur.

Imaging of renal osteodystrophy.

Chronic renal insufficiency, hemodialysis, peritoneal dialysis, renal transplantation and administration of different medications provoke complex biochemical disturbances of the calcium-phosphate metabolism with wide spectrum of bone and soft tissue abnormalities termed renal osteodystrophy. Clinically most important manifestation of renal bone disease includes secondary hyperparathyroidism, osteomalacia/rickets, osteoporosis, adynamic bone disease and soft tissue calcification. As a complication of long-term hemodialysis and renal transplantation amyloid deposition, destructive spondyloarthropathy, osteonecrosis, and musculoskeletal infections may occur. Due to more sophisticated diagnostic methods and more efficient treatment classical radiographic features of secondary hyperparathyroidism and osteomalacia/rickets are now less frequently seen. Radiological investigations play an important role in early diagnosis and follow-up of the renal bone disease. Although numerous new imaging modalities have been introduced in clinical practice (scintigraphy, CT, MRI, quantitative imaging), plain film radiography, especially fine quality hand radiograph, still represents most widely used examination.

Magnetic resonance imaging appearances of different discovertebral lesions.

Magnetic resonance imaging (MRI) is not only an excellent imaging modality for the demonstration of morphological changes but is also capable of providing pathophysiological and pathoanatomic information about various spinal diseases. Different techniques offer opportunities to demonstrate the degree of water content, the vascularity of tissue components, the accumulation of fat, and new bone production. Thus MRI closely reflects the initial phase as well as the progression of pathoanatomic changes during the evolution of a disease. Due to the high sensitivity of MRI, abnormalities are often established at an early stage of discovertebral disease, when etiological diagnosis may be difficult. The specificity of MRI findings lags behind its sensitivity; similar changes can be demonstrated in etiologically different disease entities, which reflects the limited reactive possibilities of the osteoarticular system. In fact, the MRI morphological and signal intensity features of different discovertebral lesions are commonly determined more by their location and by the reactive capabilities of disc and bone than by their etiology. Early and exact MRI differentiation of various discovertebral lesions is of the utmost clinical importance for prompt institution of appropriate therapy.

Marginal erosive discovertebral "Romanus" lesions in ankylosing spondylitis demonstrated by contrast enhanced Gd-DTPA magnetic resonance imaging.

OBJECTIVE: To assess the value of Gd-DTPA magnetic resonance (MR) imaging in the demonstration of marginal destructive discovertebral Romanus lesions in ankylosing spondylitis. DESIGN AND PATIENTS: A prospective study of Gd-DTPA MR imaging was performed in 39 patients with a clinical diagnosis of ankylosing spondylitis and typical Romanus lesions seen on radiographs of the thoracolumbar spine. MR morphological appearances and signal intensity changes at the discovertebral junctions were analysed and compared with the radiographic findings. RESULTS: Ninety-nine discovertebral junctions with Romanus lesions showed low signal intensity on T1-weighted and high signal on T2-weighted and T1-weighted postcontrast images at the vertebral corners consistent with oedematous hyperaemic inflammatory tissue. There were nine discovertebral junctions with similar MR findings but normal radiographs. Fifty-three discovertebral junctions showed syndesmophyte formation with increased signal intensity on both T1- and T2-weighted images with no contrast enhancement. Sixty-five discovertebral junctions showed a mixture of radiographic features and varied high and low signal changes at the vertebral rim on MR imaging with rims of enhancement in the vertebral body following contrast administration. CONCLUSION: Gd-DTPA MR imaging demonstrates a variable signal pattern and degree of contrast enhancement which may reflect the evolutionary stages of discovertebral enthesitis in ankylosing spondylitis. MR imaging may identify early erosive changes in radiographically normal vertebra. The role of MR imaging needs further investigation.

Osteosarcoma arising in a solitary osteochondroma of the fibula.

We present a case of osteosarcoma arising in an osteochondroma of the right fibula in a 30-year-old woman. The available radiographic studies of the lesion were not suggestive of malignant transformation. The lesion and underlying bone were excised. Histologic examination showed a conventional high-grade osteoblastic osteosarcoma that focally eroded the fibrocartilaginous cap. The patient received postoperative chemotherapy and shows no evidence of disease 27 months following operation. The occurrence of osteosarcoma in an osteochondroma is an extremely rare event, and only a few cases are on record in the literature.

Contrast enhanced Gd-DTPA magnetic resonance imaging in the evaluation of rheumatoid arthritis during a clinical trial with DMARDs. A prospective two-year follow-up study on hand joints in 31 patients.

OBJECTIVE: The aim of this prospective 24-month follow-up study was to compare clinical features with radiological and magnetic resonance imaging (MRI) findings in evaluating synovial proliferation in the hand joints of 31 patients with rheumatoid arthritis (RA). A single joint was used for the follow-up of each patient. METHODS: Thirty-one small hand joints were examined by conventional radiography and MRI before and after 24 months of treatment. MRI assessment of disease progression (volume and/or signal intensity of the synovial proliferation on T1 weighted precontrast, T1 weighted postcontrast and T2 weighted images) was compared with a clinical assessment of the chosen joints, and with a plain x-ray film evaluation (Larsen's score). RESULTS: Of 26 joints which clinically improved (14 markedly and 14 slightly) during the study, on MRI 16 showed improvement, 8 showed no change, and 2 showed deterioration. Four clinically unchanged joints appeared improved on MRI. One joint deteriorated clinically and on MRI. Overall, there was a 58% congruence between clinical and MRI findings. On x-ray 23 joints showed no change; nine of these were also unchanged on MRI, while 13 showed improvement and one deterioration. Only in 2 out of 8 joints showing deterioration on x-ray were the MRI findings in accordance. In the remaining six joints MRI showed improvement. The congruence between x-ray and MRI was therefore 36%. CONCLUSION: The long-term follow-up of rheumatoid synovial proliferation of the small joints in the hand using contrast enhanced MRI is feasible and may provide additional information regarding disease activity. Important advantages over conventional radiography methods are its ability to demonstrate qualitative differences of synovial proliferation within bone erosions, and demonstrate not only deterioration, but also the improvement of inflammatory disease.

Prognostic value of contrast enhanced Gd-DTPA MRI for development of bone erosive changes in rheumatoid arthritis.

Conventional radiograms have been used to quantitate the progression of rheumatoid arthritis, mainly through the assessment of bone erosions, but this approach has many limitations. It has been suggested that an advantage of contrast-enhanced Gd-DTPA MRI over radiography may be its prognostic value due to its ability to show the natural history of active destructive to inactive fibrous pannus. The aim of this study was to evaluate the possible prognostic value of MRI for future development of bone erosive changes in small hand joints in patients with RA. The results of the study confirm that in joints in which inflammatory active pannus is shown by contrast-enhanced MRI, progression of bone-destructive changes can be expected.

[MR imaging in seronegative spondyloarthritis]. / MR-Bildgebung bei seronegativen Spondyloarthritider.

In twenty-five patients with a clinical diagnosis of suspected sacroiliitis conventional radiography, CT and MRI were performed. In ten patients no abnormalities were demonstrated. In thirteen cases CT and MRI revealed sacroiliitis. In two patients with normal plain films and CT para- and intraarticular changes of signal intensity suggested suspicious sacroiliitis. MRI can be considered as an important imaging modality for early diagnosis of sacroiliitis. In eighteen patients with a firm diagnosis of ankylosing spondylitis and plain films of the thoracolumbar junction suggesting destructive Romanus and Anderson inflammatory lesions MRI was done. Two distinct groups of inflammatory changes were found. In ten patients MRI findings compatible with active inflammatory enthesitis were revealed at the disco-vertebral junction. In eight cases focal and linear changes of signal intensity within the intervertebral disks suggested an active inflammation. Using MRI the spectrum of inflammatory changes in sero-negative spondylitis can be presented. In sixteen patients with definite clinical diagnosis (psoriatic arthritis--thirteen cases and Reiter's syndrome--three cases) plain films and MRI of small hand joints were performed. The patients fell into two distinct groups. In the first MRI findings could not be differentiated from those seen in rheumatoid arthritis. In nine cases the distribution and extent of soft tissue findings were different, similar to changes seen in enthesitis. Therefore, on the basis of MRI findings in small peripheral joints easier differential diagnosis between sero-negative spondyloarthritides and rheumatoid arthritis is possible. In five patients with a diagnosis of Reiter's syndrome having clinical signs of enthesitis plain films and MRI of calcaneus were done. MRI revealed findings compatible with active inflammation which resembled those seen at the attachment of the annulus fibrosus and collateral ligaments of the small hand joints.

Distinctive radiological features of small hand joints in rheumatoid arthritis and seronegative spondyloarthritis demonstrated by contrast-enhanced (Gd-DTPA) magnetic resonance imaging.

A series of patients with clinically early inflammatory joint disease due to rheumatoid arthritis, psoriatic arthritis and Reiter's syndrome were examined by plain film radiography and magnetic resonance imaging (MRI). The spin echo T1-weighted precontrast, T2-weighted, and, especially, T1-weighted postcontrast images demonstrated distinct differences in the distribution of inflammatory changes, both within and adjacent to involved small hand joints. Two major subtypes of inflammatory arthritis were shown, thus providing a specific differential diagnosis between rheumatoid arthritis and some patients with seronegative spondyloarthritis. In particular, all the patients with Reiter's syndrome who were studied, and half of those with psoriatic arthritis, had a distinctive pattern of extra-articular disease involvement. The need for a new classification of clinical subsets in psoriatic arthritis has been recently suggested. The present findings suggest that magnetic resonance imaging could be useful in such a reclassification of seronegative spondyloarthritis, as well as offering considerable potential for a reappraisal of pathogenesis and therapy. In this series, it was also noted that juxta-articular osteoporosis on plain film did not correlate with bone marrow oedema on MRI. Hence the aetiology of this common radiographic finding also merits further consideration.

Precontrast and postcontrast (Gd-DTPA) magnetic resonance imaging of hand joints in patients with rheumatoid arthritis.

In an attempt to demonstrate whether clinically selected joints of the hand in active rheumatoid disease had consistent MRI findings, 45 patients were examined, in whom one joint in each was selected by both the referring clinician and patient as being active and symptomatic. Such joints, in order to be included in the study, were required to conform to ARA criteria of activity and usually mild to moderate X-ray changes. The joints were imaged using spin-echo sequences with T1W and T2W precontrast images, followed by T1W images after intravenous administration of Gd-DTPA. Different patterns of joint abnormalities were found. In 27 joints MRI findings suggested highly active synovitis and/or destructive pannus. In four, crescentic enhancement was thought to be compatible with simple synovitis, but in 23 rounded masses of synovial proliferation were characterized by marked, diffuse contrast enhancement on T1W postcontrast images, which corresponded well with high signal intensity on T2W images. Synovial proliferation in a further 12 joints was shown by only moderate stippled contrast enhancement and nonhomogeneous intermediate to high signal intensity on T2W images. These findings were thought to represent less active synovitis and pannus. MRI did not demonstrate inflammatory activity in six joints. In two of these pannus was of low signal intensity on T2W images, without contrast enhancement after Gd-DTPA infection presumed fibrotic and inert, and four were normal on all pulse sequences. These results suggest that clinical features of synovitis, even in carefully selected joints clinically, do not produce a homogeneous group when examined by MRI imaging. Indeed, a spectrum exists from presumed marked, active synovitis to total normality. If MRI is to be used as a clinical and research tool in the assessment of rheumatoid disease, and its therapeutic manipulation, these results are of some importance, since the variable findings indicate an appreciable heterogeneity of appearances in joints thought clinically to be of relatively uniform severity.