Mariusz Korkosz

Hand radiographs preprocessing, image representation in the finger regions and joint space width measurements for image interpretation

In this paper, the first stage of studies concerning the computer analysis of hand X-ray digital images is described. The images are preprocessed and then skeletization of the fingers is carried out. Then, the interphapangeal and metacarpophalangeal joints are detected and contoured. Joint widths are also measured. The obtained results largely concur with those obtained by other authors-see Beier et al. [Segmentation of medical images combining local, regional, global, and hierarchical distances into a bottom-up region merging scheme, Proc. SPIE 5747 (2005) 546-555], Klooster et al. [Automatic quantification of osteoarthritis in hand radiographs: validation of a new method to measure joint space width, Osteoarthritis and Cartilage 16 (1) (2008) 18-25], Ogiela et al. [Image languages in intelligent radiological palm diagnostics, Pattern Recognition 39 (2006) 2157-2165] and Ogiela and Tadeusiewicz [Picture languages in automatic radiological palm interpretation, Int. J. Appl. Math. Comput. Sci. 15 (2) (2005) 305-312].

Application of shape description methodology to hand radiographs interpretation

In this paper, a shape description methodology, introduced by Jakubowski [6] is applied to hand radiographs interpretation, in order to recognize bones borders shapes in the fingers regions. It is shown that the classical approach can be used only for preliminary analysis. Therefore, the improved method, based on fuzzy approach, is considered.

Identifying the borders of the upper and lower metacarpophalangeal joint surfaces on hand radiographs

In this paper, the next stage of out studies concerning the computer analysis of hand X-ray digital images is described. An algorithm identifying the borders of the upper and lower joint surfaces on hand radiographs is proposed. It is based on local segmentation and profile plots analysis. The described algorithm achieved high efficiency -mean distance distribution signature for complete borders was equal to 0.118mm. Therefore, it can be applied both to trace development of hand joints diseases and analysis of bone contour shapes using syntactic methods.

Modified jakubowski shape transducer for detecting osteophytes and erosions in finger joints

In this paper, a syntactic method of pattern recognition is applied to hand radiographs interpretation, in order to recognize erosions and osteophytes in the finger joints. It is shown that, the classical Jakubowski transducer does not distinguish contours of healthy bones from contours of affected bones. Therefore, the modifications of the transducer are introduced. It is demonstrated, that the modified transducer correctly recognizes the classes of bone shapes obtained based on the medical classification: healthy bone class, erosion bone class and osteophyte bone class.

Blood Monocyte Subsets and Selected Cardiovascular Risk Markers in Rheumatoid Arthritis of Short Duration in relation to Disease Activity

Objectives. To evaluate blood monocyte subsets and functional monocyte properties in patients with rheumatoid arthritis (RA) of short duration in the context of cardiovascular (CV) risk and disease activity. Methods. We studied conventional markers of CV risk, intima media thickness (IMT), and blood monocyte subsets in 27 patients aged 41 ± 10 years with RA of short duration (median 12 months) and 22 healthy controls. The RA subjects were divided into low (DAS28: 2.6–5.1) and high (DAS28 > 5.1) disease activity. Results. RA patients exhibited increased levels of intermediate (CD14++CD16+) monocytes with decreased CD45RA expression compared to controls, increased counts of classical (CD14++CD16−) monocytes, and decreased percentages of nonclassical (CD14+CD16++) monocytes. Patients with high disease activity had lower HLA DR expression on classical monocytes compared to low disease activity patients. There were no differences in monocyte subsets between subjects with DAS > 5.1 and DAS ≤ 5.1. There were no significant intergroup differences in IMT and the majority of classical CV risk factors. Conclusions. Patients with RA of short duration show alteration in peripheral blood monocyte subsets despite the fact that there is no evidence of subclinical atherosclerosis. Disease activity assessed with DAS28 was associated with impaired functional properties but not with a shift in monocyte subpopulations.

Baseline new bone formation does not predict bone loss in ankylosing spondylitis as assessed by quantitative computed tomography (QCT) - 10-year follow-up

BackgroundTo evaluate the relationship between bone loss and new bone formation in ankylosing spondylitis (AS) using 10-year X-ray, dual-energy x-ray absorptiometry (DXA) and quantitative computed tomography (QCT) follow-up.MethodsFifteen AS patients free from medical conditions and drugs affecting bone metabolism underwent X-ray, DXA and QCT in 1999 and 2009.ResultsIn spine QCT a statistically significant (p = 0,001) decrease of trabecular bone mineral content (BMC) was observed (change ± SD: 18.0 ± 7.3 mg/cm3). In contrast, spine DXA revealed a significant increase of bone mineral density (change ± SD: -0.15 ± 0.14 g/cm2). The mean BMC, both at baseline and follow-up was significantly lower (p = 0.02 and p = 0.005, respectively) in advanced radiological group as compared to early radiological group. However, in multiple regression model after adjustment for baseline BMC, the baseline radiological scoring did not influence the progression of bone loss as assessed with QCT (p = 0.22, p for BMC*X-ray syndesmophyte scoring interaction = 0.65, p for ANOVA-based X-ray syndesmophyte scoring*time interaction = 0.39). Baseline BMC was the only significant determinant of 10-year BMC change, to date the longest QCT follow-up data in AS.ConclusionsIn AS patients who were not using antiosteoporotic therapy spine trabecular bone density evaluated by QCT decreased over 10-year follow-up and was not related to baseline radiological severity of spine involvement.

Generalized Shape Language Application to Detection of a Specific Type of Bone Erosion in X-ray Images

X-ray imaging is crucial in diagnosis of various musculoskeletal diseases. During early disease process, the X-ray changes are often scarce and difficult to capture and the definite localization of osteophytes or erosions is often challenging. Therefore, the attempt to use computer methods to facilitate better diagnosing is of great value. Formal tools for contour description are based on string languages. In Jakubowski’s shape languages sixteen primitives are predefined. Finite collection of primitives, however is insufficient for describing natural objects because of irregular character of this type of objects. In this paper the generalized shape language, in which primitives are defined on a higher level of abstraction, is proposed and is used for description and detection of a special type of complex erosions in bone contours.

Improved fuzzy entropy algorithm for x-ray pictures preprocessing

The fuzzy entropy algorithm was designed for preprocessing of photos taken in the visible spectrum of light. However it did not produce satisfying results when it is directly applied to X-ray pictures. In this paper we present significant improvements of this approach and apply it to hand radiographs. The noise elimination and the bone contourisation is the task which is studied in this paper. Not only is the algorithm modified but also it is combined with using of median and minimum filters. The presented approach allows us to obtain satisfying noise elimination and clear bone contourisation.

Dimethylated L-arginine analogues versus autoantibodies in early rheumatoid arthritis.

Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide formation, is associated with cardiovascular (CV) risk factors, endothelial dysfunction, and adverse CV outcomes (1). Elevated plasma ADMA levels have also been reported in rheumatoid arthritis (RA) patients free of clinically evident atherosclerotic CV disease or traditional risk factors, with active disease despite disease-modifying anti-rheumatic drug (DMARD) therapy (2). In these RA patients, ADMA was related to subclinical carotid atherosclerosis (2) and anti-cyclic citrullinated peptide antibody (anti-CCP) titres (3). Turiel et al (4) have described increased ADMA in DMARD-naïve subjects with early RA without clinical CV disease or risk factors, linking raised ADMA to a depressed coronary flow reserve and higher anti-CCP. These observations suggest that anti-CCP might contribute to excessive ADMA accumulation and thus to CV pathology. In RA, the positivity for anti-CCP increased the future risk of developing clinically manifest ischaemic heart disease independently of traditional risk factors (5). Furthermore, another autoantibody, rheumatoid factor (RF), predicts CV mortality in RA (6) and in non-arthritic individuals (7). Therefore, in this study our aim was to investigate relationships between ADMA, anti-CCP, and RF isotypes in early RA. We studied 25 new-onset RA patients (17 women and eight men; mean age 44 13 years) fulfilling the revised 1987 American College of Rheumatology criteria, without overt CV disease before commencing DMARDs. Enzyme-linked immunosorbent assays (ELISAs) were used to measure plasma ADMA and its structural isomer, symmetric dimethylarginine (SDMA, DLD Diagnostika GmbH, Hamburg, Germany), secondand third-generation anti-CCP [immunoglobulin (Ig)G-anti-CCP2 and IgG/IgAanti-CCP3, respectively], and RF IgG, IgM, and IgA isotypes (INOVA Diagnostics, Inc, San Diego, CA, USA) (Table 1). The ADMA ELISA had previously been validated against high-performance liquid chromatography coupled to mass spectrometry, the golden standard for the determination of ADMA levels (8). According to the manufacturer, the lower detection limits were 0.05 μmol/L for ADMA and SDMA, and the intraand inter-assay coefficients of variation averaged 5.7% and 10.3% for ADMA and 6.1% and 9.8% for SDMA, respectively. Cross-reactivity with L-arginine and other methylarginines was < 0.01–0.02% (SDMA or ADMA vs. L-arginine), 0.44–1.2% (ADMA vs. SDMA), and 0.7–1.0% (SDMA or ADMA vs. N-monomethyl-L-arginine). Ethical approval was granted by the Bioethical Committee of our university and written consent was obtained from each participant. A positive correlation between IgG-RF levels and the ADMA/SDMA ratio was found, mainly driven by a tendency to higher ADMA concentrations at increased IgG-RF titres (Table 2). Clinical, radiological, and biochemical features (including anti-CCP and systemic inflammatory markers) were unrelated to plasma ADMA (0.94 0.23 μmol/L), SDMA (0.57 0.12 μmol/L), or the ADMA/SDMA ratio (1.69 0.36) (p > 0.1). To allow for the possibility of spurious correlations due to multiple testing, multivariate analysis was performed with ADMA or SDMA levels as dependent variables. Multiple linear regression identified IgG-RF (β 1⁄4 0.52 0.24, p 1⁄4 0.04) and age (β 1⁄4 0.43 0.21,

A Shape Description Language for Osteophytes Detection in Upper Surfaces of the Metacarpophalangeal Joints

In this paper, the successive module of the computer system for hand diseases diagnosis support is presented. Based on the upper surface borders of the metacarpophalangeal joints, syntactic description is constructed. Then, it is analysed to verify if considered border contains osteophytes. As has been presented, shape description introduced in this paper can be used to distinguish contour of the upper surface with and without osteophytes. This kind of diversification is required to build an intelligent system for joint diseases diagnosis.