| 1. |
- Doria, A S, et al.
(författare)
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Reliability and construct validity of the compatible MRI scoring system for evaluation of elbows in haemophilic children.
- 2008
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Ingår i: Haemophilia. - : Wiley. - 1351-8216 .- 1365-2516. ; 14:2, s. 303-314
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Tidskriftsartikel (refereegranskat)abstract
- Summary. We assessed the reliability and construct validity of the Compatible MRI scale for evaluation of elbows, and compared the diagnostic performance of MRI and radiographs for assessment of these joints. Twenty-nine MR examinations of elbows from 27 boys with haemophilia A and B [age range, 5–17 years (mean, 11.5)] were independently read by four blinded radiologists on two occasions. Three centres participated in the study: (Toronto, n = 24 examinations; Atlanta, n = 3; Cuiaba, n = 2). The number of previous joint bleeds and severity of haemophilia were reference standard measures. The inter-reader reliability of MRI scores was substantial (ICC = 0.73) for the additive (A)-scale and excellent (ICC = 0.83) for the progressive (P)-scale. The intrareader reliability was excellent for both P-scores (ICC = 0.91) and A-scores (ICC = 0.93). The total P- and A-scores correlated poorly (r = 0.36) or moderately (r = 0.54), but positively, with clinical-laboratory measurements. The total MRI scores demonstrated high accuracy for discrimination of presence or absence of arthropathy [P-scale, area-under-the-curve (AUC) = 0.94 ± 0.05; A-scale, AUC = 0.89 ± 0.06], as did the soft tissue scores of both scales (P-scale, AUC = 0.90 ± 0.06; A-scale, AUC = 0.86 ± 0.06). Areas-under-the-curve used to discriminate severe disease demonstrated high accuracy for both P-MRI scores (AUC = 0.83 ± 0.09) and A-MRI scores (AUC = 0.87 ± 0.09), but non-diagnostic ability to discriminate mild disease. Similar results were noted for radiographic scales. In conclusion, both MRI scales demonstrated substantial to excellent reliability and accuracy for discrimination of presence/absence of arthropathy, and severe/non-severe disease, but poor to moderate convergent validity for total scores and non-diagnostic discriminant validity for mild/non-mild disease. Compared with radiographic scores, MRI scales did not perform better for discrimination of severity of arthropathy.
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| 2. |
- Doria, A. S., et al.
(författare)
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Reliability and construct validity of the compatible MRI scoring system for evaluation of haemophilic knees and ankles of haemophilic children. Expert MRI working group of the international prophylaxis study group
- 2006
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Ingår i: Haemophilia. - : Wiley. - 1351-8216 .- 1365-2516. ; 12:5, s. 503-513
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Tidskriftsartikel (refereegranskat)abstract
- We tested the reliability and construct validity of the Compatible magnetic resonance imaging (MRI) scale for the evaluation of haemophilic knees and ankles and compared the diagnostic performance of MRI and plain film radiographs. Sagittal and coronal gradient-echo 1.5-T MR images of knees (n = 22) and ankles (n = 23) were obtained from boys (age range 4-16 years; mean 11 years) in two centres (Toronto, n = 26; Europe, n = 19). The MR images were independently read by four blinded radiologists on two occasions. Number of previous joint bleedings and laboratory level of severity of haemophilia were the reference standards for imaging assessment. Both components of the MRI scale demonstrated high inter- and intrareader intraclass correlation coefficients (progressive (P) scale, 0.91 and 0.94; additive (A) scale, 0.81 and 0.92 respectively). The correlation between the osteochondral domain of the MRI scale and patient's age was moderate. Otherwise, correlations between A- and P-scales and clinical laboratory measurements were weak. The areas under the curve (AUCs) used for discrimination of disease severity were similar for the A- and P-scales (AUCs used for mild disease, A-scale, 0.72 +/- 0.07; P-scale, 0.69 +/- 0.08; P = 0.23; AUCs for severe disease, A-scale, 0.93 +/- 0.05; P-scale, 0.87 +/- 0.08; P = 0.05). No differences were noted between the AUCs of the MRI and radiographic scales used for discrimination of late osteoarticular changes; MRI scales performed better for discrimination of early changes. In conclusion, both MRI scales demonstrated excellent reliability, poor convergent validity, and moderate and excellent validity for discrimination of mild and severe diseases respectively. Compared with radiographic scores, the MRI scales performed better for discrimination of early osteoarticular changes.
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| 3. |
- Lundin, Björn, et al.
(författare)
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Compatible scales for progressive and additive MRI assessments of haemophilic arthropathy.
- 2005
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Ingår i: Haemophilia. - : Wiley. - 1351-8216 .- 1365-2516. ; 11:2, s. 109-115
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Tidskriftsartikel (refereegranskat)abstract
- Summary. The international MRI expert subgroup of the International Prophylaxis Study Group (IPSG) has developed a consensus for magnetic resonance imaging (MRI) scales for assessment of haemophilic arthropathy. A MRI scoring scheme including a 10 step progressive scale and a 20 step additive scale with identical definitions of mutual steps is presented. Using the progressive scale, effusion/haemarthrosis can correspond to progressive scores of 1, 2, or 3, and synovial hypertrophy and/or haemosiderin deposition to 4, 5, or 6. The progressive score can be 7 or 8 if there are subchondral cysts and/or surface erosions, and it is 9 or 10 if there is loss of cartilage. Using the additive scale, synovial hypertrophy contributes 1–3 points to the additive score and haemosiderin deposition contributes 1 point. For osteochondral changes, 16 statements are evaluated as to whether they are true or false, and each true statement contributes 1 point to the additive score. The use of these two compatible scales for progressive and additive MRI assessments can facilitate international comparison of data and enhance the accumulation of experience on MRI scoring of haemophilic arthropathy.
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| 4. |
- Manco-Johnson, MJ, et al.
(författare)
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Physical therapy and imaging outcome measures in a haemophilia population treated with factor prophylaxis: current status and future directions
- 2004
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Ingår i: Haemophilia. - : Wiley. - 1351-8216 .- 1365-2516. ; 10, s. 88-93
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Tidskriftsartikel (refereegranskat)abstract
- Routine infusions of factor VIII to prevent bleeding, known as prophylaxis, and other intensive therapies are being more broadly applied to patients with haemophilia. These therapies differ widely in replacement product usage, cost, frequency of venous access and parental effort. In order to address residual issues relating to recommendations, implementation, and evaluations of prophylaxis therapy in persons with haemophila, a multinational working group was formed and called the International Prophylaxis Study Group (IPSG). The group was comprised of haemophilia treaters actively involved in studies of prophylaxis from North America and Europe. Two expert committees, the Physical Therapy (PT) Working Group and the Magnetic Resonance Imaging (MRI) Working Group were organized to critically assess existing tools for assessment of Joint outcome. These two committees independently concluded that the WFH Physical Examination Scale (WFH PE Scale) and the WFH X-ray Scale (WFH XR Scale) were inadequately sensitive to detect early changes in Joints. New scales were developed based on suggested modifications of the existing scales and called the Haemophilia joint Health Score (HJHS) and the International MRI Scales. The new scales were piloted. Concordance was measured by the intra-class correlation coefficient of variation. Reliability of the HJHS was excellent with an inter-observer co-efficient of 0.83 and a test-retest value of 0.89. The MRI study was conducted using both Denver and European scoring approaches; inter-reader reliability using the two approaches was 0.88 and 0.87; test-retest reliability was 0.92 and 0.93. These new PT and MRI scales promise to improve outcome assessment in children on early preventive treatment regimens.
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| 5. |
- Berntorp, Erik, et al.
(författare)
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Consensus perspectives on prophylactic therapy for haemophilia: summary statement.
- 2003
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Ingår i: Haemophilia. - : Wiley. - 1351-8216. ; 9:Suppl 1, s. 41278-41278
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Tidskriftsartikel (refereegranskat)abstract
- Participants in an international conference on prophylactic therapy for severe haemophilia developed a consensus summary of the findings and conclusions of the conference. In the consensus, participants agreed upon revised definitions for primary and secondary prophylaxis and also made recommendations concerning the need for an international system of pharmacovigilance. Considerations on starting prophylaxis, monitoring outcomes, and individualizing treatment regimens were discussed. Several research questions were identified as needing further investigation, including when to start and when to stop prophylaxis, optimal dosing and dose interval, and methods for assessment of long-term treatment effects. Such studies should include carefully defined cohorts, validated orthopaedic and quality-of-life assessment instruments, and cost-benefit analyses.
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| 6. |
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| 7. |
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| 8. |
- Doria, AS, et al.
(författare)
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Reliability of progressive and additive MRI scoring systems for evaluation of haemophilic arthropathy in children: Expert MRI Working Group of the International Prophylaxis Study Group
- 2005
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Ingår i: Haemophilia. - : Wiley. - 1351-8216 .- 1365-2516. ; 11:3, s. 245-253
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Tidskriftsartikel (refereegranskat)abstract
- Effective treatment of haemophilic arthropathy requires a detailed evaluation of joint integrity. Methodological assessment of magnetic resonance imaging (MRI) scores are needed to assure reproducibility of measurements when comparing results of clinical trials conducted in different centres. We compared the reliability of two MRI scoring systems for assessment of haemophilic arthropathy: one progressive system that displays the most severe change and one additive system that depicts osteochondral and soft tissue-related changes. A total of 47 1.5 T MRI examinations of knees (n = 21) and ankles (n = 26) of 42 haemophilic boys, age range, 22 months to 18 years, performed at different centres (Toronto, n = 20, Europe, n = 12 and Denver, n = 15) were independently reviewed by four radiologists at two occasions. Twenty-two examinations were from children < 9 years and 25 from children &GE; 9. Sagittal and coronal gradient-echo (MPGR, 3D FLASH with fat saturation, GRASS) images were obtained. The MRI examinations of the ankle and knee studies presented with osteochondral abnormalities in 38.5% and 23.8% of the cases respectively. The two scoring systems demonstrated an excellent inter-reader [progressive, 0.88; additive (A, e, s and h components), 0.86] and intra-reader [progressive, 0.92; additive (A, e, s and h components), 0.93] reliability using intraclass correlation coefficients (ICCs). Although ICCs were slightly higher for knees when compared with ankles, and for older children when compared with younger children, all values fell within excellent inter- and intra-reader reliability categories. The two MRI scoring systems demonstrated a comparable reliability. This result constitutes the basis for further development of a combined MRI scoring system for assessment of haemophilic arthropathy, which incorporates progressive and additive components.
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| 9. |
- Farmand, Maryam, et al.
(författare)
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Near-edge X-ray refraction fine structure microscopy
- 2017
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Ingår i: Applied Physics Letters. - : AMER INST PHYSICS. - 0003-6951 .- 1077-3118. ; 110:6
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Tidskriftsartikel (refereegranskat)abstract
- We demonstrate a method for obtaining increased spatial resolution and specificity in nanoscale chemical composition maps through the use of full refractive reference spectra in soft x-ray spectro- microscopy. Using soft x-ray ptychography, we measure both the absorption and refraction of x-rays through pristine reference materials as a function of photon energy and use these reference spectra as the basis for decomposing spatially resolved spectra from a heterogeneous sample, thereby quantifying the composition at high resolution. While conventional instruments are limited to absorption contrast, our novel refraction based method takes advantage of the strongly energy dependent scattering cross-section and can see nearly five-fold improved spatial resolution on resonance.
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| 10. |
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