Association of night shift work with dietary intake and BMI: J-MICC Okazaki Study

名古屋市立大学博士 (医学)doctoral thesi

Computed diffusion-weighted imaging for differentiating synovial proliferation from joint effusion in hand arthritis

The objective of this study is to investigate computed DWI (cDWI) as an alternative method to contrast-enhanced MRI in comparison with directory measured DWI (mDWI) and apparent diffusion coefficient (ADC) for differentiating synovial proliferation from joint effusion. Nine patients suspected with RA (5 women) were included in this study. A radiologist identified region of interest (ROI) based on STIR, and evaluated using a 5-point grading scale of 0 (fluid) to 4 (synovial proliferation) according to the degree of contrast enhancement within the ROI. cDWI was synthesized for b values from 1000 to 2000 at 200 s/mm(2) intervals using the combination of b values at mDWI. In addition to ADC values, contrast ratios were calculated using signal intensity for each ROI on the mDWI and cDWI. Visual assessment by a radiologist was conducted between pairs of STIR image and mDWI or cDWI. ROI grades were most significantly correlated with cDWI(2000) based on b values of 400-1000 s/mm(2) (r(s) = 0.405, p < 0.01). The area under the curve of cDWI(2000) based on b values of 400-1000 s/mm(2) (0.762) was larger than that of ADC values (0.570-0.608) when comparing low versus high contrast enhancement grades. Both cDWI(1800) (200-1000) and cDWI(2000) (400-1000) demonstrated high sensitivity and specificity in visual assessment (84.6% and 66.7%, respectively). The cDWI(2000) based on b values of 400-1000 s/mm(2) may be useful for noninvasive differentiation of synovial proliferation from joint effusion in hand arthritis

Pixel-by-Pixel Arterial Spin Labeling Blood Flow Pattern Variation Analysis for Discrimination of Rheumatoid Synovitis: A Pilot Study

We examined the capability of a gray-scale arterial spin labeling blood flow pattern variation (BFPV) map with two different post labeling delay (PLD) times to discriminate pannus in patients with rheumatoid arthritis (RA) at 3T. There was a statistically significant difference in the BFPV values between artery, pannus, and surrounding tissue. Furthermore, the color-coded BFPV map was able to accurately distinguish pannus from other tissues. These results suggest this approach may be capable of identifying pannus noninvasively

Composite assessment of power Doppler ultrasonography and MRI in rheumatoid arthritis: a pilot study of predictive value in radiographic progression after one year

Objective: Power Doppler ultrasonography (PDUS) and MRI are independently useful to predict structural damage in patients with rheumatoid arthritis (RA). We hypothesize that there is a complementary relationship between these modalities. The aim of this study is, therefore, to investigate the usefulness of the predictive value of composite assessment of PDUS and contrast-enhanced MRI in radiographic outcomes in patients with RA. Methods: 20 patients (17 females and 3 males) with RA on disease-modifying antirheumatic drugs underwent PDUS and MRI of both hands at baseline. Radiography of the bilateral hands was performed at baseline and at 1 year, Articular synovitis on PDUS was evaluated according to quantitative measurement. Synovitis, bone marrow edema and bone erosion were scored according to the RA MRI scoring method. The changes of joint space narrowing and bone erosion on radiograph were assessed by the Sharp/van der Heijde method. We applied t-statistics to combine the assessment of quantitative PDUS with semiquantitative MRI. Results: Structural damage progression for radiography was not correlated with any evaluations for MRI, while it showed significant correlation with synovitis on PDUS (r(s) = 0.597, p = 0.005). The composite assessment of both modalities (synovitis for PDUS and bone marrow edema for MRI) was correlated with structural damage progression on radiograph (r(s) = 0.792, p < 0.0001). Conclusion: Composite assessment of PDUS and MRI may have a stronger predictive value in radiographic progression than PDUS or MRI alone in RA. Advances In knowledge: Composite assessment of PDUS and MRI may be an effective predictor of structural damage in RA

Quantification of Hand Synovitis in Rheumatoid Arthritis: Arterial Mask Subtraction Reinforced With Mutual Information Can Improve Accuracy of Pixel-by-Pixel Time-Intensity Curve Shape Analysis in Dynamic MRI

Background: Synovitis, which is a hallmark of rheumatoid arthritis (RA), needs to be precisely quantified to determine the treatment plan. Time-intensity curve (TIC) shape analysis is an objective assessment method for characterizing the pixels as artery, inflamed synovium, or other tissues using dynamic contrast-enhanced MRI (DCE-MRI). Purpose/Hypothesis: To assess the feasibility of our original arterial mask subtraction method (AMSM) with mutual information (MI) for quantification of synovitis in RA. Study Type: Prospective study. Subjects: Ten RA patients (nine women and one man; mean age, 56.8 years; range, 38-67 years). Field Strength/Sequence: 3T/DCE-MRI. Assessment: After optimization of TIC shape analysis to the hand region, a combination of TIC shape analysis and AMSM was applied to synovial quantification. The MI between pre-and postcontrast images was utilized to determine the arterial mask phase objectively, which was compared with human subjective selection. The volume of objectively measured synovitis by software was compared with that of manual outlining by an experienced radiologist. Simple TIC shape analysis and TIC shape analysis combined with AMSM were compared in slices without synovitis according to subjective evaluation. Statistical Tests: Pearson's correlation coefficient, paired t-test and intraclass correlation coefficient (ICC). Results: TIC shape analysis was successfully optimized in the hand region with a correlation coefficient of 0.725 (P< 0.01) with the results of manual assessment regarded as ground truth. Objective selection utilizing MI had substantial agreement (ICC50.734) with subjective selection. Correlation of synovial volumetry in combination with TIC shape analysis and AMSM with manual assessment was excellent (r50.922, P< 0.01). In addition, negative predictive ability in slices without synovitis pixels was significantly increased (P< 0.01). Data Conclusions: The combination of TIC shape analysis and image subtraction reinforced with MI can accurately quantify synovitis of RA in the hand by eliminating arterial pixels. Level of Evidence: 2 Technical Efficacy: Stage