Gadolinium-DTPA enhanced magnetic resonance imaging of bone cysts in patients with rheumatoid arthritis

MRI of Large Intraosseous Lesions in Patients with Inflammatory Arthritis

OBJECTIVE

The purpose of our study was to evaluate on MRI the occurrence of large cystlike intraosseous lesions in patients with inflammatory arthritis.

SUBJECTS AND METHODS

We prospectively reviewed contrast-enhanced MR images of 128 hands and wrists in 44 patients with clinical presentation of inflammatory arthritis. Large lesions (> or = 1 cm) found on MR images were further evaluated for the presence of a cortical break and intraarticular extension. These data were correlated with clinical and laboratory findings and the duration of arthritis.

RESULTS

We found 26 patients with rheumatoid arthritis, seven with psoriatic arthritis, two with systemic lupus erythematosus, one with HIV-associated arthritis, one with mixed connective tissue disorder, one with paraneoplastic-associated arthritis, one with inflammatory bowel disease arthritis, and five patients with early unclassified inflammatory arthritis. Twelve patients had 16 large intraosseous lesions, none of which were detected on available radiographs (availability of radiographs for large erosions was 75%). A cortical break with intraarticular extension of the large lesions was seen in 12 cases. Four lesions were not intraarticular.

CONCLUSION

Even large intraosseous lesions may be occult on radiography. MRI is a superior technique for detecting these lesions in the small joints of the hand and wrist in inflammatory arthritis. Although large intraosseous erosions often communicate with joints, we observed four large purely intraosseous enhancing lesions without intraarticular connection. Patients with large erosions have a longer duration of inflammatory arthritis.

Advanced imaging of early rheumatoid arthritis

Advances in MR imaging of arthritis include contrast-enhanced, dynamic, and quantitative imaging techniques. These advances may result in MR imaging becoming the gold standard in diagnosing early RA. MR imaging is a useful technique in diagnosis, follow-up, and evaluation of remission in rheumatic diseases of the joints. Early diagnosis of RA, in the first 6 months after the onset of symptoms, may lead to earlier control and prevent future erosions and deformities.

Inter- and intrareader variability in the interpretation of two radiographic classification systems for juvenile rheumatoid arthritis

OBJECTIVE

To evaluate the inter- and intrareader variability for interpretation of a modified Larsen's radiographic classification system for juvenile rheumatoid arthritis (JRA) focused on osteochondral lesions and a conventional Larsen's classification system, compared to a reference MR scoring system of corresponding images.

MATERIALS AND METHODS

Seventy-five radiographs of 60 children with JRA, performed within a short interval of time from the MR examinations, were independently evaluated by three experienced radiologists, three diagnostic imaging residents and three rheumatologists, in two separate sessions, according to the two different classification methods, blinded to the corresponding MR images.

RESULTS

The inter- and intrareader concordance rates between the two radiographic classification systems and the MR-related radiographs were respectively poor and poor/moderate. The interobserver range of weighted kappa values for the conventional and the modified Larsen's system respectively was 0.25-0.37 vs 0.19-0.39 for radiologists, 0.25-0.37 vs 0.18-0.30 for residents and 0.19-0.51 vs 0.17-0.29 for rheumatologists. The intrareader rate ranged from 0.17-0.55 for radiologists, 0.2-0.56 for residents, and 0.14-0.59 for rheumatologists.

CONCLUSION

Although the proposal of a new radiographic classification system for JRA focused on osteochondral abnormalities sounds promising, the low inter- and intrareader concordance rates with an MR-related radiographic system makes the clinical applicability of such a radiographic system less suitable.

An appraisal of magnetic resonance imaging of the wrist in rheumatoid arthritis

OBJECTIVES

To evaluate the role of magnetic resonance imaging (MRI) in the diagnosis, staging, and follow-up of the rheumatoid wrist.

METHODS

A Medline search was performed to identify all publications from the years 1985 to 1999 concerning MRI of the wrist in patients with rheumatoid arthritis (RA). Additional papers were retrieved by scanning the references to the Medline-listed articles. Details of the MRI technique, as well as clinical data, were analyzed and compared.

RESULTS

A total of 55 papers were identified. There were considerable variations in imaging sequence, section type, and slice thickness. Erosions and synovitis were the conditions that mostly profited from the adoption of MRI. Although the visualization of erosions was better detailed with MRI than with conventional radiography, erosions were only rarely related to clinical and laboratory parameters. Another advantage was that synovitis imaging, which can be enhanced by contrast agents, was amenable to quantitation. The extent of the synovial surface and the rate of contrast enhancement in a series of consecutive, rapidly acquired images were the most common measures.

CONCLUSIONS

MRI of the rheumatoid wrist is a useful technique to ascertain the criteria for diagnosis and progression of RA, and to monitor the effects of treatment. Implementation of a standardized protocol could further increase its value.

Low-field magnetic resonance imaging of early subchondral cyst-like lesions in induced cranial cruciate ligament deficient dogs

Six healthy adult male mongrel dogs underwent cranial cruciate ligament transection in the left stifle. Survey radiography of both stifles and low-field (0.064 T) MRI of the left stifle were performed preoperatively and at 2, 6, and 12 weeks postoperatively. Focal changes in signal intensity were seen with MRI in the subchondral bone of the medial tibial condyle at 2 and 6 weeks postoperatively. At 12 weeks postoperative, a cyst-like lesion was detected using MRI in the subchondral bone of the medial tibial condyle in 4 of 6 dogs and a less defined lesion at this site in the remaining 2 dogs. The cyst-like lesion was spherical in shape and showed typical characteristics of fluid with low signal intensity on T1-weighted images, high signal intensity on T2-weighted images and high signal intensity on inversion recovery images. The lesion was seen in the subchondral bone of the caudal medial and/or middle region of the tibial plateau slightly cranial to the insertion of the caudal cruciate ligament. No subchondral cysts were seen in the tibia on radiographs. Histopathologically, the tibia was characterized by a loose myxomatous phase of early subchondral cyst formation.

The rheumatoid wrist: bilateral MR analysis of the distribution of rheumatoid lesions in axial plan in a female population

In this case-control study, we analyzed 146 wrists: a) to search for the distribution pattern of the rheumatoid lesions and, b) to correlate the distribution pattern of these lesions with the clinical parameters. Thirty-one patients with rheumatoid arthritis (RA) and 42 controls-all women-were examined by means of a bilateral MR fast field echo (FFE) sequence, in axial plan. The wrist was divided into three regions: metacarpal (level I), carpal (level II) and radioulnar (level III). Erosions were present in thirty (97%) patients and in six (14%) controls. They were asymmetrically distributed at all levels, mainly at level II. Marrow infiltration and bone destruction were seen in 35% of the patients in an asymmetrical pattern at level I and II, respectively. These lesions were absent in the control group. Subchondral cysts were asymmetrically present in both groups-in 48% of the patients at levels II and III, and in 11% of the controls at level II. In the patient group, this asymmetrical pattern of the lesions correlated with the disease duration at levels I and II (p = 0.011 and p = 0.013, respectively). Most lesions were found at the radial force-bearing column of the wrist, more in the right side. Synovial hypertrophy and hyperintense median nerve were evident in 96% and 70% of the patients, respectively. We concluded that contrary to common belief rheumatoid damages to the carpal bones become rather asymmetrical as the disease progresses. The line of force along the radial side of the wrist possibly influences the distribution pattern of the rheumatoid lesions.