Andrea S Doria

SickKids, Toronto, Ontario, Canada

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Publications (89)215.06 Total impact

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    ABSTRACT: The purpose of this article is to evaluate virtual monochromatic spectral imaging and metal artifact reduction software for reducing metal artifact and to compare it with conventional single-energy CT (SECT) in an animal model. Postmortem juvenile (n = 5) and adult (n = 1) swine specimens were scanned with SECT followed by a dual-energy CT (DECT) pediatric protocol after the insertion of two rods into their paraspinal thoracolumbar regions. Virtual monochromatic spectral images were extrapolated from DECT images at five monoenergetic levels (64, 69, 75, 88, and 105 keV) with and without the use of metal artifact reduction software. Images were evaluated by a 5-point scoring system for the extent of metallic artifacts and image interpretability in soft-tissue and bone windows. The density in the most pronounced artifact was measured. CT dose index was recorded. In studies without metal artifact reduction software, higher energy reconstructions resulted in fewer artifacts and better image interpretability in both soft-tissue and bone windows (p < 0.0001). Artifact density decreased from -792 HU at 64 keV to -128 HU at 105 keV without the use of metal artifact reduction software. No difference was noted in attributes' scores or in artifact density in studies using metal artifact reduction software (p > 0.05). DECT studies showed lower scores compared with SECT with regard to all attributes. A new faint perimetallic hypodense halo was seen in all studies with metal artifact reduction software. The CT dose index of DECT was 1.18-3.56 times higher than that of SECT techniques. DECT at all energy levels with metal artifact reduction software and higher energy extrapolations without metal artifact reduction software reduced metallic artifact and enhanced image interpretability compared with SECT. Radiation dose with DECT could be significantly higher than SECT.
    American Journal of Roentgenology 09/2015; 205(3):W352-W359. DOI:10.2214/AJR.14.12547 · 2.74 Impact Factor
  • Magdy Soliman · Ronald Laxer · David Manson · Rae Yeung · Andrea S Doria
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    ABSTRACT: The term "systemic vasculitis" encompasses a diverse set of diseases linked by the presence of blood-vessel inflammation that are often associated with critical complications. These diseases are uncommon in childhood and are frequently subjected to a delayed diagnosis. Although the diagnosis and treatment may be similar for adult and childhood systemic vasculitides, the prevalence and classification vary according to the age group under investigation. For example, Kawasaki disease affects children while it is rarely encountered in adults. In 2006, the European League Against Rheumatism (EULAR) and the Pediatric Rheumatology European Society (PReS) proposed a classification system for childhood vasculitis adopting the system devised in the Chapel Hill Consensus Conference in 1993, which categorizes vasculitides according to the predominant size of the involved blood vessels into small, medium and large vessel diseases. Currently, medical imaging has a pivotal role in the diagnosis of vasculitis given recent developments in the imaging of blood vessels. For example, early diagnosis of coronary artery aneurysms, a serious complication of Kawasaki disease, is now possible by magnetic resonance imaging (MRI) of the heart and multidetector computed tomography (MDCT); positron emission tomography/CT (PET/CT) helps to assess active vascular inflammation in Takayasu arteritis. Our review offers a unique approach using the integration of the proposed classification criteria for common systemic childhood vasculitides with their most frequent imaging findings, along with differential diagnoses and an algorithm for diagnosis based on common findings. It should help radiologists and clinicians reach an early diagnosis, therefore facilitating the ultimate goal of proper management of affected children.
    Pediatric Radiology 07/2015; 45(8):1110-25. DOI:10.1007/s00247-015-3339-3 · 1.65 Impact Factor
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    ABSTRACT: To report on the progress of an ongoing research collaboration on magnetic resonance imaging (MRI) in juvenile idiopathic arthritis (JIA) and describe the proceedings of a meeting, held prior to Outcome Measures in Rheumatology (OMERACT) 12, bringing together the OMERACT MRI in JIA working group and the Health-e-Child radiology group. The goal of the meeting was to establish agreement on scoring definitions, locations, and scales for the assessment of MRI of patients with JIA for both large and small joints. The collaborative work process included premeeting surveys, presentations, group discussions, consensus on scoring methods, pilot scoring, conjoint review, and discussion of a future research agenda. The meeting resulted in preliminary statements on the MR imaging protocol of the JIA knee and wrist and determination of the starting point for development of MRI scoring systems based on previous studies. It was also considered important to be descriptive rather than explanatory in the assessment of MRI in JIA (e.g., "thickening" instead of "hypertrophy"). Further, the group agreed that well-designed calibration sessions were warranted before any future scoring exercises were conducted. The combined efforts of the OMERACT MRI in JIA working group and Health-e-Child included the assessment of currently available material in the literature and determination of the basis from which to start the development of MRI scoring systems for both the knee and wrist. The future research agenda for the knee and wrist will include establishment of MRI scoring systems, an atlas of MR imaging in healthy children, and MRI protocol requisites.
    The Journal of Rheumatology 05/2015; DOI:10.3899/jrheum.141276 · 3.17 Impact Factor
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    ABSTRACT: The primary objective was to determine the diagnostic accuracy of a serial ultrasound (US) clinical diagnostic pathway to detect appendicitis in children presenting to the emergency department (ED). The secondary objective was to examine the diagnostic performance of the initial and interval US and to compare the accuracy of the pathway to that of the initial US. This was a prospective cohort study of 294 previously healthy children 4 to 17 years old with suspected appendicitis and baseline pediatric appendicitis scores of ≥2, who were managed with the serial US clinical diagnostic pathway. This pathway consisted of an initial US followed by a clinical reassessment in each patient and an interval US and surgical consultation in patients with equivocal initial US and persistent concern about appendicitis. The USs were interpreted by published criteria as positive, negative, or equivocal for appendicitis. Children in whom this pathway did not rule in or rule out appendicitis underwent computed tomography (CT). Cases with missed appendicitis, negative operations, and CTs after the pathway were considered inaccurate. The primary outcome was the diagnostic accuracy of the serial US clinical diagnostic pathway. The secondary outcomes included the test performance of the initial and interval US imaging studies. Of the 294 study children, 111 (38%) had appendicitis. Using the serial US clinical diagnostic pathway, 274 of 294 children (93%, 95% confidence interval [CI] = 90% to 96%) had diagnostically accurate results: 108 of the 111 (97%) appendicitis cases were successfully identified by the pathway without CT scans (two missed and one CT), and 166 of the 183 (91%) negative cases were ruled out without CT scans (14 negative operations and three CTs). The sensitivity of this pathway was 108 of 111 (97%, 95% CI = 94% to 100%), specificity 166 of 183 (91%, 95% CI = 87% to 95%), positive predictive value 108 of 125 (86%; 95% CI = 79% to 92%), and negative predictive value 166 of 169 (98%, 95% CI = 96% to 100%). The diagnostic accuracy of the pathway was higher than that of the initial US alone (274 of 294 vs. 160 of 294; p < 0.0001). Of 123 patients with equivocal initial US, concern about appendicitis subsided on clinical reassessment in 73 (no surgery and no missed appendicitis). Of 50 children with persistent symptoms, 40 underwent interval US and 10 had surgical consultation alone. The interval US confirmed or ruled out appendicitis in 22 of 40 children (55.0%) with equivocal initial US, with one false-positive interval US. The serial US clinical diagnostic pathway in suspected appendicitis has an acceptable diagnostic accuracy that is significantly higher than that of the initial US and results in few CT scans. This approach appears most useful in children with equivocal initial US, in whom the majority of negative cases were identified at clinical reassessment and appendicitis was diagnosed by interval US or surgical consultation in most study patients. © 2015 by the Society for Academic Emergency Medicine.
    Academic Emergency Medicine 03/2015; 22(4). DOI:10.1111/acem.12631 · 2.20 Impact Factor
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    ABSTRACT: The study was undertaken to document cartilage and soft tissue changes/findings in ankles and knees of normal children of different age groups to be used for comparison in the assessment of children with haemophilia. Cartilage thickness and soft tissue changes were recorded at predetermined sites of ankles/knees on both US and MRI in healthy boys in three age groups: 7-9; 10-14; and 15-18 years. To assess the validity of the ultrasound and MRI measurements, an ex vivo study was done using agar phantoms with techniques and scanners similar to those applied in vivo. Twenty (48%) knees and 22 (52%) ankles of 42 boys, were evaluated. There was a reduction in the thickness of joint cartilage with age. A difference in cartilage measurements was noted in most sites between the age groups on both US and MRI (P < 0.05 each), but such difference was not noted for joint fluid in ankles or knees (P = 0.20, P = 0.68 or P = 0.75, P = 0.63 for US, MRI, respectively). Although cartilage measurements were smaller on US than on MRI for both ankles and knees (P < 0.05 each), this observation was not recorded for fluid in knees (P = 0.02). For diminutive measurements (2 mm) mean US measurements were smaller than corresponding phantom's measurements, P = 0.02. Age-related measurements were noted for cartilage thickness on US and MRI in ankles and knees. US measurements were smaller than corresponding MRI measurements at most joint sites, which were supported by results on small-diameter phantoms. © 2015 John Wiley & Sons Ltd.
    Haemophilia 03/2015; 21(3). DOI:10.1111/hae.12614 · 2.47 Impact Factor
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    ABSTRACT: OBJECTIVE. The purpose of this article is to assess the reliability of interpretation of ultrasound findings according to data blinding in maturing hemophilic joints and to determine the diagnostic accuracy of ultrasound compared with MRI for assessing joint components. SUBJECTS AND METHODS. Ankles (n = 34) or knees (n = 25) of boys with hemophilia or von Willebrand disease (median age, 13 years; range, 5-17 years) were imaged by ultrasound, MRI, and radiography in two centers (Toronto, Canada, and Vellore, India). Ultrasound scans were performed by two operators (one blinded and one unblinded to MRI data) and were reviewed by four reviewers who were unblinded to corresponding MRI findings according to a proposed 0- to 14-item scale that matches 14 of 17 items of the corresponding MRI scale. MRI examinations were independently reviewed by two readers. RESULTS. When data were acquired by radiologists, ultrasound was highly reliable for assessing soft-tissue changes (intraclass correlation coefficient [ICC], 0.98 for ankles and 0.97 for knees) and substantially to highly reliable for assessing osteochondral changes (ICC, 0.61 for ankles and 0.89 for knees). Ultrasound was highly sensitive (> 92%) for assessing synovial hypertrophy and hemosiderin in both ankles and knees but had borderline sensitivity for detecting small amounts of fluid in ankles (70%) in contrast to knees (93%) and variable sensitivity for evaluating osteochondral abnormalities (sensitivity range, 86-100% for ankles and 12-100% for knees). CONCLUSION. If it is performed by experienced radiologists using a standardized protocol, ultrasound is highly reliable for assessing soft-tissue abnormalities of ankles and knees and substantially to highly reliable for assessing osteochondral changes in these joints.
    American Journal of Roentgenology 03/2015; 204(3):W336-47. DOI:10.2214/AJR.14.12501 · 2.74 Impact Factor
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    ABSTRACT: Involvement of the TMJ in children with JIA may lead to facial growth disturbances, pain and/or impaired jaw function. For the prevention of such complications, early diagnosis of TMJ arthritis is paramount and a prerequisite for early treatment. Since clinical signs and symptoms from the TMJs frequently are absent, imaging plays a major role in diagnostic assessment. In earlier studies conventional methods were applied, predominantly panoramic radiography. In the last decade MRI has become the new standard for examining these joints because both joint inflammation and joint damage can be evaluated. This review will briefly focus on imaging modalities to assess JIA in the TMJ, imaging manifestations of JIA in the TMJ, frequency of TMJ involvement on imaging, clinical predictors of TMJ involvement, relationship between TMJ involvement on imaging and facial growth disturbance, longitudinal TMJ studies, image-guided intra-articular injections, differential diagnoses, and future need for research.
    Seminars in Orthodontics 02/2015; 21(2). DOI:10.1053/j.sodo.2015.02.006
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    ABSTRACT: Ultrasmall paramagnetic iron oxide (USPIO)-enhanced MRI is promising for evaluating inflammation. The aims of this study were to investigate the effect of USPIO on cartilage T1 and T2 mapping, and to evaluate a proposed rapid vs. conventional T2 map method for imaging cartilage in a blood-induced arthritis model. Knees of nine arthritic (induction by intra-articular autologous blood injection) and six control rabbits were imaged over time (baseline, weeks 1, 5, 10) by 1.5T MRI. All rabbits had USPIO (35–75 μmol Fe/kg)-enhanced MRI at each time point. T1 and T2 (conventional and rapid) maps and signal-to-noise ratios (SNR) were obtained pre- and post-USPIO administration. Cartilage biochemistry and histology were compared with MRI. Excellent correlations were noted between T1 map values and histologic scores at week 10 pre-USPIO (medial, r = 0.93, P = 0.0007; lateral, r = 0.87, P = 0.005) in the arthritic group, but not between T2 map and histology. Marginally and significant differences were observed between pre- and post-USPIO T2 values at weeks 5 (P = 0.06) and 10 (P = 0.02), but only with the administration of high USPIO doses in the arthritic group using the conventional method. No significant differences were noted between pre- and post-USPIO T1 values at any imaging time points. Cartilage T2 maps with short-TR and conventional protocols provided similar T2 values [(decreased trend)] (P > 0.05). Concomitant use of USPIO to T1 and T2 mapping of cartilage would not impair the identification of interval changes of T1 and T2 maps. Rapid T2 map provides similar results compared to conventional method, but its validation warrants further investigation.
    Haemophilia 01/2015; 21(1). DOI:10.1111/hae.12601 · 2.47 Impact Factor
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    ABSTRACT: Our aim was to test the feasibility of blood oxygen level dependent magnetic resonance imaging (BOLD MRI) and dynamic contrast-enhanced (DCE) MRI to monitor periarticular hypoxic/inflammatory changes over time in a juvenile rabbit model of arthritis. We examined arthritic and contralateral nonarthritic knees of 21 juvenile rabbits at baseline and days 1,14, and 28 after induction of arthritis by unilateral intra-articular injection of carrageenin with BOLD and DCE MRI at 1.5 Tesla (T). Nine noninjected rabbits served as controls. Associations between BOLD and DCE-MRI and corresponding intra-articular oxygen pressure (PO2) and blood flow [blood perfusion units (BPU)] (polarographic probes, reference standards) or clinical-histological data were measured by correlation coefficients. Percentage BOLD MRI change obtained in contralateral knees correlated moderately with BPU on day 0 (r = -0.51, p = 0.02) and excellently on day 28 (r = -0.84, p = 0.03). A moderate correlation was observed between peak enhancement DCE MRI (day 1) and BPU measurements in arthritic knees (r = 0.49, p = 0.04). In acute arthritis, BOLD and DCE MRI highly correlated (r = 0.89, p = 0.04; r = 1.0, p < 0.0001) with histological scores in arthritic knees. The proposed techniques are feasible to perform at 1.5 T, and they hold potential as surrogate measures to monitor hypoxic and inflammatory changes over time in arthritis at higher-strength MRI fields. aEuro cent BOLD and DCE MRI detect interval perisynovial changes in a rabbit knee aEuro cent BOLD and DCE MRI act as surrogate markers of physiologic changes in arthritis aEuro cent BOLD MRI signal represents oxygen extraction compared with intra-articular PO (2) aEuro cent DCE MRI measurements estimate physiologic periarticular vascular properties aEuro cent In rabbit knees with acute arthritis, BOLD/DCE MRI highly correlated with histological scores.
    European Radiology 09/2014; 24(11). DOI:10.1007/s00330-014-3331-6 · 4.34 Impact Factor
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    ABSTRACT: To assess the sequence and type of active joints in a cohort of newly diagnosed juvenile idiopathic arthritis (JIA) patients with full access to current treatment at first visit and during a follow-up period of 5-years, in order to identify an index joint/group of joints for magnetic resonance imaging in JIA. Patient charts of all consecutive newly diagnosed JIA patients with a follow-up duration of at least 5 years were analyzed. Patients were derived from two tertiary pediatric rheumatology centers. Patient characteristics and data concerning the presence of joints with arthritis and the use of medication were recorded. Findings from 95 JIA patients [39 (41 %) oligoarticular and 56 (59 %) polyarticular] were analyzed. At first visit, distribution of active joints among patients was as follows: knee (n = 70, 74 %), ankle (n = 55, 58 %), elbow (n = 23, 24 %), wrist (n = 23, 24 %), metacarpophalangeal (MCP) (n = 20, 21 %), proximal interphalangeal (PIP) (n = 13, 14 %), hip (n = 6, 6 %), shoulder (n = 5, 5 %), and distal interphalangeal (DIP) (n = 4, 4 %) joints. After a follow-up period of 5 years, the cumulative percentage of patients with specific joint involvement changed into: knee (n = 88, 93 %), ankle (n = 79, 83 %), elbow (n = 43, 45 %), wrist (n = 38, 40 %), MCP (n = 36, 38 %), PIP (n = 29, 31 %), shoulder (n = 20, 21 %), hip (n = 17, 19 %), and DIP (n = 9, 10 %) joints. Despite changes in treatment strategies over the years, the knee remains the most commonly involved joint at onset and during follow-up in JIA, followed by the ankle, elbow, and wrist. For the evaluation of outcome with MRI, the knee appears the most appropriate joint in JIA.
    Rheumatology International 08/2014; 35(2). DOI:10.1007/s00296-014-3108-x · 1.63 Impact Factor
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    ABSTRACT: Dual-energy absorptiometry (DXA) is the current reference standard for assessing pediatric osteoporosis; however due to its areal nature, it has limitations. Thus, quantitative ultrasound (QUS), a modality free of ionizing radiation, has been proposed as a potential surrogate for DXA.
    Pediatric Radiology 06/2014; 44(12). DOI:10.1007/s00247-014-3041-x · 1.65 Impact Factor
  • Andrea S. Doria · Björn Lundin
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    ABSTRACT: Arthropathy due to recurrent hemarthroses is the main cause of morbidity in patients with hemophilia. Radiologic methods can be used for the evaluation of joint changes to make therapeutic decisions and to compare treatment regimens. X-ray is well established for such purposes, but lacks the capability for the assessment of early joint changes that are important for the evaluation of prophylactic regimens. Magnetic resonance imaging (MRI), by contrast, visualizes early joint changes, and currently is the preferred imaging modality for hemophilic arthropathy in many situations; however, it is a complex and expensive technique that is not practical for use in all settings. Ultrasonography is a cheaper and more available diagnostic tool that in some instances can replace and even offer advantages to MRI, but does not have the capability for a complete joint evaluation.
    Textbook of Hemophilia, 04/2014: pages 237-246; , ISBN: 9781118398241
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    ABSTRACT: Traumatic lumbar punctures with blasts (TLP+) in children with acute lymphoblastic leukaemia (ALL) obscure central nervous system status and are associated with a poorer event-free survival (EFS). We conducted a retrospective cohort study of all lumbar punctures (LPs) for children with ALL diagnosed at our institution from 2005 to 2009. We utilised random-effects and fixed-effects repeated-measures logistic regression analyses to identify risk factors for TLPs. Fixed-effects models use each patient as his or her own control. We used survival analysis to describe outcomes after a TLP+. 264 children underwent 5267 evaluable lumbar punctures (LPs), of which 944 (17.9%) were traumatic. In the multivariable random-effects model, variables significantly associated with TLPs were age <1year (odds ratio (OR) 3.46, 95% confidence interval (CI) 2.06-5.81) or age ⩾10years (OR 2.00, CI 1.66-2.40); body mass index percentile ⩾95 (OR 1.44, CI 1.19-1.75); platelet count <100×10(3)/μL (OR 1.49, CI 1.08-20.7); fewer days since previous LP (OR 5.13, CI 2.34-11.25 for ⩾16days versus 0-3days); and a preceding TLP (OR 1.43, CI 1.19-1.73). In the fixed-effects model, image-guidance reduced the odds of TLP (OR 0.55, CI 0.32-0.95). The 5-year EFS (±SE) for children with TLP+ (77±8%) was significantly lower than for children with CNS1 status (93±2%; p=0.002). The frequency of TLP remains high. Consistent with previous studies, a TLP+ at diagnosis was associated with a poorer EFS. These risk factors can allow identifying interventions to reduce TLPs and directing interventions to those at highest risk.
    European journal of cancer (Oxford, England: 1990) 03/2014; DOI:10.1016/j.ejca.2014.02.021 · 4.82 Impact Factor
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    ABSTRACT: Recent advances in hemophilia prophylaxis have raised the need for accurate noninvasive methods for assessment of early cartilage damage in maturing joints to guide initiation of prophylaxis. Such methods can either be semiquantitative or quantitative. Whereas semiquantitative scores are less time-consuming to be performed than quantitative methods, they are prone to subjective interpretation. To test the feasibility of a manual segmentation and a quantitative methodology for cross-sectional evaluation of articular cartilage status in growing ankles of children with blood-induced arthritis, as compared with a semiquantitative scoring system and clinical-radiographic constructs. Twelve boys, 11 with hemophilia (A, n = 9; B, n = 2) and 1 with von Willebrand disease (median age: 13; range: 6-17), underwent physical examination and MRI at 1.5 T. Two radiologists semiquantitatively scored the MRIs for cartilage pathology (surface erosions, cartilage loss) with blinding to clinical information. An experienced operator applied a validated quantitative 3-D MRI method to determine the percentage area of denuded bone (dAB) and the cartilage thickness (ThCtAB) in the joints' MRIs. Quantitative and semiquantitative MRI methods and clinical-radiographic constructs (Hemophilia Joint Health Score [HJHS], Pettersson radiograph scores) were compared. Moderate correlations were noted between erosions and dAB (r = 0.62, P = 0.03) in the talus but not in the distal tibia (P > 0.05). Whereas substantial to high correlations (r range: 0.70-0.94, P < 0.05) were observed between erosions, cartilage loss, HJHS and Pettersson scores both at the distal tibia and talus levels, moderate/borderline substantial (r range: 0.55-0.61, P < 0.05) correlations were noted between dAB/ThCtAB and clinical-radiographic constructs. Whereas the semiquantitative method of assessing cartilage status is closely associated with clinical-radiographic scores in cross-sectional studies of blood-induced arthropathy, quantitative measures provide independent information and are therefore less applicable for that research design.
    Pediatric Radiology 02/2014; 44(5). DOI:10.1007/s00247-013-2872-1 · 1.65 Impact Factor
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    ABSTRACT: OBJECTIVE. Our objective was to evaluate the diagnostic accuracy and reliability of MRI and its ability to depict responsiveness to treatment for the evaluation of the axial joints (temporomandibular joint [TMJ], spinal joints, and sacroiliac joints) in juvenile idiopathic arthritis (JIA). CONCLUSION. There is fair (grade B) evidence that MRI is an accurate diagnostic method for evaluating early and intermediate changes in the TMJ in JIA and insufficient evidence to indicate MRI is an accurate diagnostic method for detecting JIA in the spinal (grade I) and sacroiliac (grade I) joints.
    American Journal of Roentgenology 01/2014; 202(1):199-210. DOI:10.2214/AJR.12.10475 · 2.74 Impact Factor
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    ABSTRACT: Blood-oxygen-level-dependent (BOLD) MRI has the potential to identify regions of early hypoxic and vascular joint changes in inflammatory arthritis. There is no standard protocol for analysis of BOLD MRI measurements in musculoskeletal disorders. To optimize the following BOLD MRI reading parameters: (1) statistical threshold values (low, r > 0.01 versus high, r > 0.2); (2) summary measures of BOLD contrast (percentage of activated voxels [PT%] versus percentage signal difference between on-and-off signal intensities [diff_on_off]); and (3) direction of BOLD response (positive, negative and positive + negative). Using BOLD MRI protocols at 1.5 T, arthritic (n = 21) and contralateral (n = 21) knees of 21 juvenile rabbits were imaged at baseline and on days 1, 14 and 28 after a unilateral intra-articular injection of carrageenan. Nine non-injected rabbits served as external control knees (n = 18). By comparing arthritic to contralateral knees, receiver operating characteristic curves were used to determine diagnostic accuracy. Using diff_on_off and positive + negative responses, a threshold of r > 0.01 was more accurate than r > 0.2 (P = 0.03 at day 28). Comparison of summary measures yielded no statistically significant difference (P > 0.05). Although positive + negative (AUC = 0.86 at day 28) and negative responses (AUC = 0.90 at day 28) for PT% were the most diagnostically accurate, positive + negative responses for diff_on_off (AUC = 0.78 at day 28) also had acceptable accuracy. The most clinically relevant reading parameters included a lower threshold of r > 0.01 and a positive + negative BOLD response. We propose that diff_on_off is a more clinically relevant summary measure of BOLD MRI, while PT% can be used as an ancillary measure.
    Pediatric Radiology 12/2013; 44(5). DOI:10.1007/s00247-013-2844-5 · 1.65 Impact Factor
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    ABSTRACT: Recent advances in magnetic resonance imaging (MRI) techniques have substantially improved the evaluation of joint pathologies in juvenile idiopathic arthritis (JIA). Because of the current availability of highly effective antirheumatic therapies and the unique and useful features of MRI, there is a growing need for an accurate and reproducible MRI assessment scoring system for JIA, such as the rheumatoid arthritis MRI Scoring (RAMRIS) for patients with rheumatoid arthritis (RA). To effectively evaluate the efficacy of treatment in clinical research trials, we need to develop and validate scoring methods to accurately measure joint outcomes, standardize imaging protocols for data acquisition and interpretation, and create imaging atlases to differentiate physiologic and pathologic joint findings in childhood and adolescence. Such a standardized, validated, JIA-MRI scoring method could be used as an outcome measure in clinical trials.
    The Journal of Rheumatology 11/2013; DOI:10.3899/jrheum.131081 · 3.17 Impact Factor
  • M W Chan · A Leckie · F Xavier · E Uleryk · S Tadros · V Blanchette · A S Doria
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    ABSTRACT: Our purposes were to determine: (i) whether there is direct evidence that currently available MRI techniques are accurate for early diagnosis of pathological findings in haemophilic arthropathy; (ii) whether there is an MRI scoring system that best correlates with clinical/radiological constructs for evaluation of haemophilic arthropathy; (iii) whether there is an MRI scoring system that best correlates with clinical/radiological constructs for evaluation of haemophilic arthropathy. Articles were screened using MEDLINE (n = 566), EMBASE (n = 201), and the Cochrane Library (n = 1). Two independent reviewers assessed articles for inclusion under the overarching purposes of the review by using the Standards for Reporting of Diagnostic Accuracy (STARD) tool, and the quality of the studies were graded using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. The electronic literature search retrieved 777 references (after duplicates were removed). A total of 32 studies were chosen for inclusion from the results of the search and review of bibliographical references. Using the STARD tool, seven studies were of excellent quality of reporting, and using the QUADAS-2 tool, 10 studies were judged to be of adequate quality. There is 'fair' evidence to recommend MRI as an accurate test for detecting evidence of haemophilic arthropathy and the use of second or third generation MRI scales for assessing haemophilic arthropathy. However, there is no evidence that screening of early intra-articular soft tissue bleed with MRI improves the functional status of joints over time.
    Haemophilia 08/2013; 19(6). DOI:10.1111/hae.12248 · 2.47 Impact Factor
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    Clinics (São Paulo, Brazil) 05/2013; 68(5). DOI:10.6061/clinics/2013(05)22 · 1.42 Impact Factor

Publication Stats

1k Citations
215.06 Total Impact Points

Institutions

  • 2001–2015
    • SickKids
      • Department of Diagnostic Imaging
      Toronto, Ontario, Canada
    • University of Toronto
      • • Department of Medical Imaging
      • • Hospital for Sick Children
      • • Institute of Health Policy, Management and Evaluation
      Toronto, Ontario, Canada
  • 2007
    • University College London
      • Institute of Child Health
      London, ENG, United Kingdom
  • 2006
    • University of Tasmania
      • Menzies Research Institute
      Hobart Town, Tasmania, Australia
  • 2003
    • Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo
      San Paulo, São Paulo, Brazil
  • 2001–2002
    • University of São Paulo
      • Faculty of Medicine (FM)
      San Paulo, São Paulo, Brazil