[Polycythemia vera and D-dimer-negative thromboembolism]. / D-Dimer-negative Thromboembolien bei Polycythaemia vera.

CASE REPORT: A 65-year-old patient with polycythemia vera (PV) was admitted with a painful edema of the right arm lasting for 24 h. The D-dimer assay was negative. By phlebography the patient was diagnosed with a fresh thrombosis of the right subclavian vein. 1 week later she developed a D-dimer-negative symptomatic pulmonary embolism. CONCLUSION: If clinical signs of a thromboembolic event are present, the negative predictive value of the D-dimer assay is not sufficient to abandon further definitive diagnosis. Since thromboembolic events are frequent in PV patients, a prophylactic treatment with low-dose acetylsalicylic acid is recommended.

Impact of chronic LDL-apheresis treatment on Achilles tendon affection in patients with severe familial hypercholesterolemia: a clinical and ultrasonographic 3-year follow-up study.

OBJECTIVE: Pain of Achilles tendon (AT) is a common symptom in patients with severe familial hypercholesterolemia (FH) and often associated with AT xanthomas. It is unknown if these changes are potentially reversible during lipid lowering treatment. LDL-apheresis (LA) represents the most effective lipid lowering regimen. Aim of this investigation was to determine clinical and ultrasonographic reduction of AT xanthomas in patients with severe FH undergoing regular LA. METHODS: At baseline, patient history of 22 patients with FH undergoing LA was obtained and their 44 ATs were evaluated clinically and with ultrasound for the presence of xanthomas. Three years later, both examinations of ATs could be repeated at follow-up visits in 16 patients. AT thickness and changes in echo structure were assessed at both points of time and compared to each other as well as to a healthy control group (n = 21). ROC analysis was performed to identify the optimal cut-off in AT thickness between healthy and affected ATs. RESULTS: Twelve of 22 FH patients suffered from AT pain at least once during their life-time. At baseline, AT thickness was significantly increased compared to the healthy control group (mean sagittal diameter 10.1 +/- 3.6 mm). At follow-up, AT thickness was significantly reduced to 8.2 +/- 3.3 mm (mean) under LA, whereas changes in echo structure were less distinct between both visits. Conversely, in the control group, mean AT thickness was 5.2 +/- 0.6 mm. The optimal cut-off between healthy and affected ATs was determined to be 6mm. CONCLUSIONS: Ultrasonographic changes of the AT (thickening and changes in echo structure) are frequent in patients with severe FH, even if xanthomas are not clinically evident. LA treatment has the capability to reduce AT xanthomas and thickness. Ultrasound may give information about diagnosis and follow-up of AT affection in patients with FH.

Sagittal laser optical tomography for imaging of rheumatoid finger joints.

We present a novel optical tomographic imaging system that was designed to determine two-dimensional spatial distribution of optical properties in a sagittal plane through finger joints. The system incorporates a single laser diode and a single silicon photodetector into a scanning device that records spatially resolved light intensities as they are transmitted through a finger. These data are input to a model-based iterative image reconstruction (MOBIIR) scheme, which uses the equation of radiative transfer (ERT) as a forward model for light propagation through tissue. We have used this system to obtain tomographic images of six proximal interphalangeal finger joints from two patients with rheumatoid arthritis. The optical images were compared to clinical symptoms and ultrasound images.

Classification of rheumatoid joint inflammation based on laser imaging.

We describe a classification system for a novel imaging method for arthritic finger joints. The basis of this system is a laser imaging technique which is sensitive to the optical characteristics of finger joint tissue. From the laser images acquired at baseline and follow-up, finger joints can automatically be classified according to whether the inflammatory status has improved or worsened. To perform the classification task, various linear and kernel-based systems were implemented and their performances were compared. Based on the results presented in this paper, we conclude that the laser-based imaging permits a reliable classification of pathological finger joints, making it a sensitive method for detecting arthritic changes.

Is musculoskeletal ultrasonography an operator-dependent method or a fast and reliably teachable diagnostic tool? Interreader agreements of three ultrasonographers with different training levels.

Objectives. To assess interreader agreements and a learning curve between three (senior, junior, and beginner) different experienced musculoskeletal ultrasonographers. Senior served as the imaging "gold standard". Methods. Clinically dominant joints (finger, shoulder, knee, tibiotalar, and talonavicular) of 15 rheumatoid arthritis (RA) patients were examined by three different experienced ultrasonographers (senior 10 years, junior 10 months, and beginner one month). Each patient's ultrasonographic findings were reported unaware of the other investigators' results. κ coefficients, percentage agreements, sensitivities, and specificities were calculated. Results. 120 joints of 15 RA patients were evaluated. Comparing junior's and beginner's results each to the senior's findings, the overall κ for all examined joints was 0.83 (93%) for junior and 0.43 (76%) for beginner. Regarding the different joints, junior's findings correlate very well with the senior's findings (finger joints: κ = 0.82; shoulder: κ = 0.9; knee: κ = 0.74; tibiotalar joint: κ = 0.84; talonavicular joint: κ = 0.84) while beginner's findings just showed fair to moderate agreements (finger joints: κ = 0.4; shoulder: κ = 0.42; knee: κ = 0.4; tibiotalar joint: κ = 0.59; talonavicular joint: κ = 0.35). In total, beginner's results clearly improved from κ = 0.34 (agreement of 67%) at baseline to κ = 0.78 (agreement of 89%) at the end of the evaluation period. Conclusions. Ultrasonographic evaluation of a ten-month-experienced investigator in comparison to a senior ultrasonographer was of substantial agreement. Agreements between a beginner and a highly experienced ultrasonographer were only fair at the beginning, but during the study including ultrasonographical sessions of 15 RA patients, the beginner clearly improved in musculoskeletal ultrasonography.

Computer-aided interpretation approach for optical tomographic images.

A computer-aided interpretation approach is proposed to detect rheumatic arthritis (RA) in human finger joints using optical tomographic images. The image interpretation method employs a classification algorithm that makes use of a so-called self-organizing mapping scheme to classify fingers as either affected or unaffected by RA. Unlike in previous studies, this allows for combining multiple image features, such as minimum and maximum values of the absorption coefficient for identifying affected and not affected joints. Classification performances obtained by the proposed method were evaluated in terms of sensitivity, specificity, Youden index, and mutual information. Different methods (i.e., clinical diagnostics, ultrasound imaging, magnet resonance imaging, and inspection of optical tomographic images), were used to produce ground truth benchmarks to determine the performance of image interpretations. Using data from 100 finger joints, findings suggest that some parameter combinations lead to higher sensitivities, while others to higher specificities when compared to single parameter classifications employed in previous studies. Maximum performances are reached when combining the minimum/maximum ratio of the absorption coefficient and image variance. In this case, sensitivities and specificities over 0.9 can be achieved. These values are much higher than values obtained when only single parameter classifications were used, where sensitivities and specificities remained well below 0.8.

Reliability exercise for the polymyalgia rheumatica classification criteria study: the oranjewoud ultrasound substudy.

Objective. A study supported by the EULAR and the ACR being conducted to establish classification criteria for polymyalgia rheumatica (PMR) will include ultrasound examination of the shoulders and hips. Ultrasound (US) depicts glenohumeral joint effusion, biceps tenosynovitis, subdeltoid bursitis, hip joint synovitis, and trochanteric bursitis in PMR. These findings may aid in distinguishing PMR from other diseases. The purpose of this study was to assess standards and US interreader agreement of participants in the PMR classification criteria study. Methods. Sixteen physicians in four groups examined shoulders and hips of 4 patients and 4 healthy adults with ultrasound. Overall agreement and interobserver agreement were calculated. Results. The overall agreement (OA) between groups was 87%. The OA for healthy shoulders was 88.8%, for healthy hips 100%, for shoulders with pathology 85.2%, and 74.3% for hips with pathology, respectively. Conclusion. There was a high degree of agreement found for the examination of healthy shoulders and pathologic hips. Agreement was moderate for pathologic shoulders and perfect for healthy hips. US of shoulder and hips performed by different examiners is a reliable and feasible tool for assessment of PMR related disease pathology and can be incorporated into a classification criteria study.

Diagnostic quality and scoring of synovitis, tenosynovitis and erosions in low-field MRI of patients with rheumatoid arthritis: a comparison with conventional MRI.

OBJECTIVE: To compare dedicated low-field MRI (lfMRI) with conventional MRI (cMRI) in the detection and scoring of synovitis, tenosynovitis and erosions in patients with rheumatoid arthritis. PATIENTS AND METHODS: The wrist and finger joints of 17 patients with rheumatoid arthritis (median (range) disease duration 8 years (7-12); Disease Activity Score 3.3 (2.6-4.5)) were examined by 0.2 T lfMRI and 1.5 TcMRI. The protocols comprised coronal spin-echo and three-dimensional gradient-echo sequences before and after contrast medium administration. Synovitis of the metacarpophalangeal and proximal interphalangeal joints 2-5 and the wrist joints was scored according to Outcome Measures in Rheumatology recommendations. Tenosynovitis and erosions were scored using 4-point and 6-point scales, respectively. The results were analysed by calculating kappa values and performing McNemar's test intra-individually on a joint-by-joint basis. RESULTS: Agreement between the two MRI techniques was good to excellent for synovitis and erosions, and moderate for tenosynovitis. Of the 306 joints evaluated, 245 and 200 joints showed synovitis in lfMRI and cMRI, respectively. Scoring of synovitis of the finger joints yielded kappa values from 0.69 to 0.94. Of the 68 flexor tendons evaluated, tenosynovitis was diagnosed by lfMRI in 24 and by cMRI in 33 instances. Of the 391 bones evaluated, 154 and 139 showed erosions in lfMRI and cMRI, respectively. kappa values for erosion scores were between 0.65 and 1. CONCLUSION: Dedicated, lfMRI shows high agreement with cMRI in diagnosing and scoring synovitis, tenosynovitis and erosions in rheumatoid arthritis when using standardised scoring systems.

Summary findings of a systematic review of the ultrasound assessment of synovitis.

This report presents the results of a recent systematic review performed by the OMERACT Ultrasound Group on the metric properties of ultrasound for the detection of synovitis in inflammatory arthritis. Reviews were conducted for the hand, wrist, elbow, shoulder, knee, ankle, and foot; most reports were related to the hand and knee, and the most common disease process was rheumatoid arthritis. The review highlights the current gaps in the literature, including a lack of reliability data with respect to intra-occasion and intra- and inter-reader reliability. Current work by our group is addressing these issues.

The OMERACT Ultrasound Group: status of current activities and research directions.

Ultrasound (US) is a relatively new imaging modality in rheumatology that offers great potential as a diagnostic and management tool. In 2004, an OMERACT Ultrasound Special Interest Group was formed to address the metric qualities of US as a potential outcome measure. A preliminary systematic review highlighted the deficiencies in the literature, particularly with regard to the reliability of interpreting and acquiring images; as a consequence, a number of exercises were proposed to address these issues. This report describes a series of iterative studies that have resulted in improved intra- and inter-reader reliability for detecting and scoring synovitis from both static and real-time images of the hand joints of patients with rheumatoid arthritis. The reliability of acquiring images was also enhanced using standardized positions. Future studies will assess the value of US in clinical trials.

Development of a finger joint phantom for evaluation of frequency domain measurement systems.

For development and test of new optical imaging devices, phantoms are widely used to emulate the tissue to be imaged. Phantom design gets more difficult the more complex the tissue is structured. We report on developing and testing a solid, stable finger joint phantom to simulate transillumination of finger joints in frequency-domain imaging systems. The phantom consists of the bone, capsule, skin, the capsule volume, and the joint gap. Silicone was used to build the solid parts and a glycerol-water solution for the fluid in the capsule volume and joint gap. The system to test the phantom is an optical frequency-domain scanning set-up. Different stages of joint inflammation as they occur in rheumatoid arthritis (BA) were emulated by assembling the phantom with capsule and fluid having different optical properties. Reliability of the phantom measurement was investigated by repeated assembling. The results show clear discrimination between different stages of joints within the signal deviation due to reassembling of the phantom.

Comparison of two and three-dimensional optical tomographic image reconstructions of human finger joints.

We have developed an images reconstruction algorithm to recover spatial distribution of optical properties in human finger joints for early diagnosis and monitoring of rheumatoid arthritis (RA). An optimization method iteratively employs a light propagation and scattering coefficients distribution for near-infrared (NIR) light inside the joint tissue. We developed the differences in cross-sectional images obtained by using the reconstruction algorithms with 2-dimensional and 3-dimensional light propagation models. In particular we examined how these different approaches affect the discrimination between healthy and RA joints.

A novel ultrasonographic synovitis scoring system suitable for analyzing finger joint inflammation in rheumatoid arthritis.

OBJECTIVE: To develop an ultrasonographic (US) synovitis scoring system suitable for evaluation of finger joint inflammation in patients with active rheumatoid arthritis (RA) and to compare semiquantitative US scoring with quantitative US measurements. METHODS: US was performed at the palmar and dorsal sides of the second through fifth metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints in 10 healthy subjects and in the clinically more affected hand in 46 RA patients. Ten patients additionally underwent magnetic resonance imaging (MRI). Synovitis was measured, standardized, and scored according to a semiquantitative method. The 2 methods (semiquantitative US scoring, quantitative US) were compared and statistical cutoffs were identified using receiver operating characteristic (ROC) curve analysis. MRI results were compared with semiquantitative US scoring and quantitative US results. The optimal US scoring method from 6 joint combinations was identified (ROC curve analysis). RESULTS: Synovitis was most frequently detected in the palmar proximal area (86% of affected joints). We found no significant differences between individual PIP joints or between individual MCP joints, indicating that all fingers within each of these joint groups should be treated equally for statistical calculations, although each joint group as a whole should be treated separately. The optimal cutoff point to distinguish between "health" and "pathology" was 0.6 mm both for MCP joints (sensitivity 94%, specificity 89%) and for PIP joints (sensitivity 90%, specificity 88%). There was no significant difference between semiquantitative US scores and quantitative US measurements. The best results for joint combinations were achieved using the "sum of 4 fingers" (second through fifth MCP and PIP joints) and "sum of 3 fingers" (second through fourth MCP and PIP joints) methods. Comparison of MRI results with semiquantitative US scores revealed high concordance. CONCLUSION: US evaluation of finger joint synovitis can be considerably simplified by focusing on the palmar side and by applying semiquantitative grading instead of quantitative measurements. For evaluation of treatment efficacy based on synovitis in RA patients, we recommend using the "sum of 3 fingers" method in longitudinal trials.

Assessment of proximal finger joint inflammation in patients with rheumatoid arthritis, using a novel laser-based imaging technique.

OBJECTIVE: To evaluate a newly developed laser-based imaging technique for the study of soft tissue changes and acute inflammatory processes of the proximal interphalangeal (PIP) joints in patients with rheumatoid arthritis (RA). METHODS: A novel imaging device was developed which allows the transillumination of PIP joints using laser light in the near-infrared wavelength range. In a first clinical followup study, a total of 72 PIP joints of 22 patients with RA and 64 PIP joints of 8 healthy controls were examined both clinically and with the new laser device. At baseline and at followup after a mean of 6 weeks, clinical signs of synovitis, the joint circumference, and the degree of pain were assessed for each PIP joint in order to determine the clinical degree of inflammation. Different features were extracted from the laser images and evaluated by a neural network. RESULTS: At baseline, 72 PIP joints in the RA patients showed clinical signs of inflammation. At followup, 45 PIP joints showed clinical improvement, 13 showed steady active inflammation, and 14 showed deterioration compared with the first visit. None of the 64 PIP joints in the healthy individuals showed any signs of synovitis. The inflammatory status of 60 of the 72 RA joints examined was classified correctly by laser examination and joint circumference determination, giving a sensitivity of 80%, a specificity of 89%, and an accuracy of 83% in detecting inflammatory changes in affected joints. Laser data and joint circumference determination of healthy joints at followup resulted in an accuracy of 85% in reproducing the image. CONCLUSION: The new laser-based imaging technique allows the transillumination of PIP joints and gives information about the inflammatory status of the joint after processing through a neural network. Our data indicate that laser imaging may provide additional information in the early diagnosis of an inflammatory joint process and may prove particularly useful in assessing acute joint inflammation at followup.