Oei, E.H.G.

Image registration improves human knee cartilage T1 mapping with delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) (Article)

2013-01-01T00:00:00Z

Objectives: To evaluate the effect of automated registration in delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) of the knee on the occurrence of movement artefacts on the T1 map and the reproducibility of region-of-interest (ROI)-based measurements. Methods: Eleven patients with early-stage knee osteoarthritis and ten healthy controls underwent dGEMRIC twice at 3 T. Controls underwent unenhanced imaging. ROIs were manually drawn on the femoral and tibial cartilage. T1 calculation was performed with and without registration of the T1-weighted images. Automated three-dimensional rigid registration was performed on the femur and tibia cartilage separately. Registration quality was evaluated using the square root Cramér-Rao lower bound (CRLBσ). Additionally, the reproducibility of dGEMRIC was assessed by comparing automated registration with manual slice-matching. Results: Automated registration of the T1-weighted images improved the T1 maps as the 90% percentile of the CRLBσwas significantly (P < 0.05) reduced with a median reduction of 55.8ms (patients) and 112.9ms (controls). Manual matching and automated registration of the re-imaged T1 map gave comparable intraclass correlation coefficients of respectively 0.89/0.90 (patients) and 0.85/0.85 (controls). Conclusions: Registration in dGEMRIC reduces movement artefacts on T1 maps and provides a good alternative to manual slice-matching in longitudinal studies. Key Points: • Quantitative MRI is increasingly used for biomedical assessment of knee articular cartilage • Image registration leads to more accurate quantification of cartilage quality and damage • Movement artefacts in delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) are reduced • Automated image registration successfully aligns baseline and follow-up dGEMRIC examinations • Reproducibility of dGEMRIC with registration is similar to that using manual slice-matching

Reproducibility of 3D delayed gadolinium enhanced MRI of cartilage (dGEMRIC) of the knee at 3.0 T in patients with early stage osteoarthritis (Article)

2012-08-13T00:00:00Z

Objectives: To assess the reproducibility of 3D delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) at 3 T in early stage knee osteoarthritis (OA) patients. Methods: In 20 patients, 3D dGEMRIC at 3 T was acquired twice within 7 days. To correct for patient motion during acquisition, all images were rigidly registered in 3D. Eight anatomical cartilage ROIs were analysed on both images of each patient. Capability of dGEMRIC to yield T1 maps that reproducibly distinguish spatial differences in cartilage quality was assessed in two ROIs within a single slice in each patient. Reproducibility was assessed using ICCs and Bland-Altman plots. Results: ICCs ranged from 0.87 to 0.95, indicating good reproducibility. T1 maps revealed reproducible spatial differences in cartilage quality (ICC 0.79). Based on the Bland-Altman plots, we defined a threshold of 95 ms to determine if a change in dGEMRIC outcome in longitudinal research was statistically significant. Conclusions: 3D knee dGEMRIC at 3 T combined with 3D image registration is a highly reproducible measure of cartilage quality in early stage OA. Therefore, dGEMRIC may be a valuable tool in the non-invasive evaluation of cartilage quality changes in longitudinal research in patients with early stage OA and focal cartilage defects. Key Points: • Delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) can assess osteoarthritis • dGEMRIC yields highly reproducible T1 values in early stage osteoarthritic patients • A threshold was established to determine significant changes in dGEMRIC outcomes • dGEMRIC can be used to evaluate cartilage quality in longitudinal research

CT arthrography of the human knee to measure cartilage quality with low radiation dose (Article)

2012-07-01T00:00:00Z

Objective: Recently, CT arthrography (CTa) was introduced as a non-destructive technique to quantitatively measure cartilage quality in human knees. This study investigated whether this is also possible using lower radiation dose CT protocols. Furthermore, we studied the ability of (lower radiation) CTa to distinguish between local sulphated glycosaminoglycan (sGAG) content differences. Design: Of ten human cadaveric knee joints, six CT scans using different radiation doses (81.33-8.13 mGy) were acquired after intra-articular ioxaglate injection. The capability of CTa to measure overall cartilage quality was determined in seven anatomical regions of interest (ROIs), using equilibrium partitioning of an ionic contrast agent using (EPIC)-microCT (μCT) as reference standard for sGAG content. To test the capability of CTa to spatially distinguish between local differences in sGAG content, we calculated the percentage of pixels incorrectly predicted as having high or low sGAG content by the different CTa protocols. Results: Low radiation dose CTa correlated well with EPIC-μCT in large ROIs (R = 0.78; R2= 0.61; P < 0.0001). CTa can also distinguish between high and low sGAG content within a single slice. However, the percentage of incorrectly predicted quality pixels increases (from 35% to 41%) when less radiation is used. This makes is hard or even impossible to differentiate between spatial differences in sGAG content in the lowest radiation scans. Conclusions: CTa acquired using low radiation exposure, comparable to a regular knee CT, is able to measure overall cartilage quality. Spatial sGAG distribution can also be determined using CTa, however for this purpose a higher radiation dose is necessary. Nevertheless, radiation dose reduction makes CTa suitable for quantitative analysis of cartilage in clinical research.

Phenotypic spectrum of the SMAD3-related aneurysms-osteoarthritis syndrome (Article)

2012-01-01T00:00:00Z

Background: Aneurysmseosteoarthritis syndrome (AOS) is a new autosomal dominant syndromic form of thoracic aortic aneurysms and dissections characterised by the presence of arterial aneurysms and tortuosity, mild craniofacial, skeletal and cutaneous anomalies, and early-onset osteoarthritis. AOS is caused by mutations in the SMAD3 gene. Methods: A cohort of 393 patients with aneurysms without mutation in FBN1, TGFBR1 and TGFBR2 was screened for mutations in SMAD3. The patients originated from The Netherlands, Belgium, Switzerland and USA. The clinical phenotype in a total of 45 patients from eight different AOS families with eight different SMAD3 mutations is described. In all patients with a SMAD3 mutation, clinical records were reviewed and extensive genetic, cardiovascular and orthopaedic examinations were performed. Results Five novel SMAD3 mutations (one nonsense, two missense and two frame-shift mutations) were identified in five new AOS families. A follow-up description of the three families with a SMAD3 mutation previously described by the authors was included. In the majority of patients, early-onset joint abnormalities, including osteoarthritis and osteochondritis dissecans, were the initial symptom for which medical advice was sought. Cardiovascular abnormalities were present in almost 90% of patients, and involved mainly aortic aneurysms and dissections. Aneurysms and tortuosity were found in the aorta and other arteries throughout the body, including intracranial arteries. Of the patients who first presented with joint abnormalities, 20% died suddenly from aortic dissection. The presence of mild craniofacial abnormalities including hypertelorism and abnormal uvula may aid the recognition of this syndrome. Conclusion: The authors provide further insight into the phenotype of AOS with SMAD3 mutations, and present recommendations for a clinical work-up.

Quantifying osteoarthritic cartilage changes accurately using in vivo microCT arthrography in three etiologically distinct rat models (Article)

2011-11-01T00:00:00Z

In vivo microCT arthrography (μCTa) can be used to measure both quantity (volumetric) and quality (glycosaminoglycan content) of cartilage. This study investigated the accuracy of four segmentation techniques to isolate cartilage from μCTa datasets and then used the most accurate one to investigate if the μCTa method could show osteoarthritic changes in rat models during longitudinal follow-up. Volumetric measurements and glycosaminoglycan contents of patellar cartilage from in vivo μCTa-scans were compared with an ex vivo gold standard μCT-scan. Cartilage was segmented with three global thresholds and one local threshold algorithm. Comparisons were made for healthy and osteoarthritic cartilage. Next, three rat models were investigated for 24 weeks using μCTa. Osteoarthritis was induced by injection with a chemical (mono-iodoacetate), a surgical intervention (grooves applied in articular cartilage), and via exercise (strenuous running). After euthanasia, all knee joints were isolated for histology. Local thresholds accurately segmented cartilage from in vivo μCTa scans and best measured cartilage quantity and glycosaminoglycan content. Each of the three osteoarthritic rat models showed a specific pattern of osteoarthritis progression. All μCTa results were comparable to histology. In vivo μCTa is a sensitive technique for imaging cartilage degradation. Local thresholds enhanced the sensitivity of this method and will probably more accurately detect disease-modulating effects from interventional strategies. The data from rat models may serve as a reference for the time sequence of cartilage degeneration during in vivo testing of new strategies in osteoarthritis treatment. Copyright

Clinically applied CT arthrography to measure the sulphated glycosaminoglycan content of cartilage (Article)

2011-10-01T00:00:00Z

Objective: Similar to delayed gadolinium enhanced MRI of cartilage, it might be possible to image cartilage quality using CT arthrography (CTa). This study assessed the potential of CTa as a clinically applicable tool to evaluate cartilage quality in terms of sulphated glycosaminoglycan content (sGAG) and structural composition of the extra-cellular matrix (ECM). Methods: Eleven human cadaveric knee joints were scanned on a clinical CT scanner. Of each knee joint, a regular non-contrast CT (ncCT) and an ioxaglate injected CTa scan were performed. Mean X-ray attenuation of both scans was compared to identify contrast influx in seven anatomical regions of interest (ROIs). All ROIs were rescanned with contrast-enhanced μCT, which served as the reference standard for sGAG content. Mean X-ray attenuation from both ncCT and CTa were correlated with μCT results and analyzed with linear regression. Additionally, residual values from the linear fit between ncCT and μCT were used as a covariate measure to identify the influence of structural composition of cartilage ECM on contrast diffusion into cartilage in CTa scans. Results: CTa resulted in higher X-ray attenuation in cartilage compared to ncCT scans for all anatomical regions. Furthermore, CTa correlated excellent with reference μCT values (sGAG) (R=0.86; R2=0.73; P<0.0001). When corrected for structural composition of cartilage ECM, this correlation improved substantially (R=0.95; R2=0.90; P<0.0001). Conclusions: Contrast diffusion into articular cartilage detected with CTa correlates with sGAG content and to a lesser extent with structural composition of cartilage ECM. CTa may be clinically applicable to quantitatively measure the quality of articular cartilage.

Predictive factors for new onset or progression of knee osteoarthritis one year after trauma: MRI follow-up in general practice (Article)

2011-07-01T00:00:00Z

Objective: To prospectively evaluate prognostic factors for new onset or progression of degenerative change on follow-up MRI one year after knee trauma and the association with clinical outcome. Methods: Within a prospective observational cohort study in general practice, we studied a subgroup of 117 patients with acute knee trauma (mean age 41 years, 43% women). Degenerative change was scored on MRI at baseline and after one year follow-up. Multivariate logistic regression analysis was performed to evaluate prognostic factors for new onset or progressive degenerative change on follow-up MRI. Association between new or progressive degeneration and clinical outcome after one year was assessed. Results: On follow-up MRI 15% of patients with pre-existing knee osteoarthritis showed progression and 26% of patients demonstrated new degenerative change. The only statistically significant prognostic variable in the multivariate analysis was bone marrow oedema on initial MRI (OR 5.29 (95% CI 1.64-17.1), p∈=∈0.005). A significant association between new or progressive degenerative change and clinical outcome was found (p∈=∈0.003). Conclusion: Bone marrow oedema on MRI for acute knee injury is strongly predictive of new onset or progression of degenerative change of the femorotibial joint on follow-up MRI one year after trauma, which is reflected in clinical outcome.

Mutations in SMAD3 cause a syndromic form of aortic aneurysms and dissections with early-onset osteoarthritis (Article)

2011-02-01T00:00:00Z

Thoracic aortic aneurysms and dissections are a main feature of connective tissue disorders, such as Marfan syndrome and Loeys-Dietz syndrome. We delineated a new syndrome presenting with aneurysms, dissections and tortuosity throughout the arterial tree in association with mild craniofacial features and skeletal and cutaneous anomalies. In contrast with other aneurysm syndromes, most of these affected individuals presented with early-onset osteoarthritis. We mapped the genetic locus to chromosome 15q22.2-24.2 and show that the disease is caused by mutations in SMAD3. This gene encodes a member of the TGF-β pathway that is essential for TGF-β signal transmission. SMAD3 mutations lead to increased aortic expression of several key players in the TGF-β pathway, including SMAD3. Molecular diagnosis will allow early and reliable identification of cases and relatives at risk for major cardiovascular complications. Our findings endorse the TGF-β pathway as the primary pharmacological target for the development of new treatments for aortic aneurysms and osteoarthritis.

MRI follow-up of conservatively treated meniscal knee lesions in general practice (Article)

2010-01-01T00:00:00Z

Objective: To evaluate meniscal status change on follow-up MRI after 1 year, prognostic factors and association with clinical outcome in patients with conservatively treated knee injury. Methods: We analysed 403 meniscal horns in 101 conservatively treated patients (59 male; mean age 40 years) in general practice who underwent initial knee MRI within 5 weeks of trauma. We performed ordinal logistic regression analysis to analyse prognostic factors for meniscal change on follow-up MRI after 1 year, and we assessed the association with clinical outcome. Results: On follow-up MRI 49 meniscal horns had deteriorated and 18 had improved. Age (odds ratio [OR] 1.3/decade), body weight (OR 1.2/10 kg), total anterior cruciate ligament (ACL) rupture on initial MRI (OR 2.4), location in the posterior horn of the medial meniscus (OR 3.0) and an initial meniscal lesion (OR 0.3) were statistically significant predictors of meniscal MRI appearance change after 1 year, which was not associated with clinical outcome. Conclusion: In conservatively treated patients, meniscal deterioration on follow-up MRI 1 year after trauma is predicted by higher age and body weight, initial total ACL rupture, and location in the medial posterior horn. Change in MRI appearance is not associated with clinical outcome.

Magnetic Resonance Imaging for Traumatic Knee Injury (Doctoral Thesis)

2009-03-04T00:00:00Z

Traumatic knee lesions are frequently encountered both in general practice and in the hospital setting. These injuries are often caused by sports and other physical activities and may lead to severe pain and disability.

Costs and effectiveness of a brief MRI examination of patients with acute knee injury (Article)

2009-02-01T00:00:00Z

The aim of this study was to assess the costs and effectiveness of selective short magnetic resonance imaging (MRI) in patients with acute knee injury. A model was developed to evaluate the selective use of MRI in patients with acute knee injury and no fracture on radiography based on the results of a trial in which 208 patients were randomized between radiography only and radiography plus MRI. We analyzed medical (diagnostic and therapeutic) costs, quality of life, duration of diagnostic workup, number of additional diagnostic examinations, time absent from work, and time to convalescence during a 6-month follow-up period. Quality of life was lowest (EuroQol at 6 weeks 0.61 (95% CI 0.54–0.67)); duration of diagnostic workup, absence from work, and time to convalescence were longest; and the number of diagnostic examinations was largest with radiography only. These outcomes were more favorable for both MRI strategies (EuroQol at 6 weeks 0.72 (95% CI 0.67–0.77) for both). Mean total costs were 2,593 euros (95% CI 1,815–3,372) with radiography only, 2,116 euros (95% CI 1,488–2,743) with radiography plus MRI, and 1,973 euros (95% CI 1,401–2,543) with selective MRI. The results suggest that selective use of a short MRI examination saves costs and potentially increases effectiveness in patients with acute knee injury without a fracture on radiography.

Value of information analysis used to determine the necessity of additional research: MR imaging in acute knee trauma as an example (Article)

2008-02-01T00:00:00Z

Purpose: To help guide future outcomes research regarding the use of magnetic resonance (MR) imaging in patients with acute knee trauma in an emergency department setting, with use of prospective data from a randomized clinical trial and value of information analysis. Materials and Methods: A total of 189 patients (123 male, 66 female; mean age, 33.4 years) were randomly assigned to undergo radiography alone (n = 93) or radiography and MR imaging (n = 96). Institutional review board approval and informed consent (parental consent for minors) were obtained. During 6 months of follow-up, data on quality of life and 39 cost parameters were collected. Value-of-information analysis was used to estimate the expected benefit of future research to eliminate the decision uncertainty that remained after trial completion. In addition, the parameters that were responsible for most of the decision uncertainty were identified, the expected benefits of various study designs were evaluated, and the optimal sample size was estimated. Results: Only three parameters were responsible for most of the decision uncertainty: number of quality-adjusted life-years, cost of an overnight hospital stay, and friction costs. A study in which data on these three parameters are gathered would have an optimal sample size of 3500 patients per arm and would be expected to result in a societal benefit of €5.6 million or 70 quality-adjusted life-years. Conclusion: The optimal study design for use of MR imaging to evaluate acute knee trauma involves a trial in which there are 3500 patients per trial arm, and data on the number of quality-adjusted life-years, cost of an overnight hospital stay, and friction costs are collected.

MRI for Traumatic Knee Injury: A Review (Article)

2007-04-01T00:00:00Z

Magnetic resonance imaging (MRI) is a well-established technique for detecting internal derangements of the knee joint with high diagnostic accuracy. It is an effective tool to select patients for targeted therapeutic arthroscopy. In this article, indications for knee MRI and most commonly used MRI techniques are outlined, followed by an overview of the most frequently encountered traumatic knee derangements in daily practice and their appearance and grading system on MRI. Lesions discussed include fractures, osteochondral lesions, bone bruise, cruciate and collateral ligament lesions, and meniscal tears. Finally, common pitfalls and recent developments in knee MRI are addressed.

Acute peripheral joint injury: cost and effectiveness of low-field- strength MR imaging--results of randomized controlled trial. (Article)

2005-09-01T00:00:00Z

PURPOSE: To assess prospectively if a short imaging examination performed with low-field-strength dedicated magnetic resonance (MR) imaging in addition to radiography is effective and cost saving compared with the current diagnostic imaging strategy (radiography alone) in patients with recent acute traumatic injury of the wrist, knee, or ankle. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. Patients with recent trauma of the wrist, knee, or ankle were randomized across two diagnostic strategies: radiography alone (reference group) or radiography followed by a short MR imaging examination (intervention group). Measures of effectiveness included the number of additional diagnostic procedures, time to last diagnostic procedure, and number of days absent from work. Measures of effectiveness were analyzed by using an exact Wilcoxon-Mann-Whitney test. Time to convalescence and quality of life were analyzed by using a t test. Cost analysis was performed from a societal perspective and analyzed by using a t test. RESULTS: Five hundred patients (207 women, 293 men; mean age, 34.8 years) with acute injury of the wrist, knee, or ankle were randomized. In the intervention group, quality of life for patients with knee injuries was significantly higher during the first 6 weeks, and time to completion of diagnostic work-up was significantly shorter (mean, 3.5 days for intervention group vs 17.3 days for reference group). The number of additional diagnostic procedures was significantly lower in the intervention group versus the reference group (nine vs 35, respectively) for patients with knee injuries. Patients with knee injuries showed the largest difference in costs (intervention group, 1820 [$1966]; reference group, 2231 [$2409]) owing to a reduction in productivity loss. Costs were higher in patients with wrist injuries and almost equal in patients with ankle injuries. All cost differences, however, were not significant. CONCLUSION: Compared with radiography, MR imaging in patients with acute wrist or ankle injuries is neither cost saving nor effective in expediting diagnostic work-up or improving quality of life. In patients with knee injuries, a short MR imaging examination shortens the time to completion of diagnostic work-up, reduces the number of additional diagnostic procedures, improves quality of life in the first 6 weeks, and may reduce costs associated with lost productivity.

Acute wrist trauma: value of a short dedicated extremity MR imaging examination in prediction of need for treatment (Article)

2005-01-01T00:00:00Z

PURPOSE: To assess predictive value of a short magnetic resonance (MR) imaging examination in addition to or instead of radiography in patients with acute wrist trauma to identify patients who require additional treatment versus those who do not and can be discharged without further follow-up. MATERIALS AND METHODS: Informed consent was obtained from all participating patients; the institutional review board approved the randomized controlled trial and use of data to create prediction models. Of 90 patients (37 female, 53 male; mean age, 40.0 years), 87 with acute wrist trauma were randomized to undergo radiography (n = 43) or radiography and a short MR imaging examination with low-field-strength dedicated extremity MR system (n = 44). Age, sex, trauma mechanism, presence of tenderness of the anatomic snuffbox, radiographic results, MR imaging results, and treatment data were collected. Univariable and multivariable logistic regression analysis was used to create four models for prediction of treatment need. RESULTS: Thirty-six patients had one or more fractures; one patient had a marked soft-tissue lesion. In univariable analysis, age (odds ratio, 1.02; 95% confidence interval: 1.00, 1.05), anatomic snuffbox tenderness (odds ratio, 2.31; 95% confidence interval: 0.90, 5.96), radiographic results (odds ratio, 31.2; 95% confidence interval: 8.90, 109), and positive MR imaging results versus MR imaging not performed (odds ratio, 1.86; 95% confidence interval: 0.57, 6.06) were significantly predictive of treatment need. In multivariable analysis, radiographic results (odds ratio, 24.7; 95% confidence interval: 6.59, 93.1) and positive MR imaging results (odds ratio, 6.28; 95% confidence interval: 1.27, 31.0) were significantly predictive of treatment need. Negative MR imaging results were not significantly predictive (odds ratio, 0.87; 95% confidence interval: 0.20, 3.82). CONCLUSION: A short MR imaging examination with a low-field-strength MR imaging system following radiography in initial evaluation of patients with acute wrist trauma has additional value in prediction of treatment need; it does not have value in identification of patients who can be discharged without further follow-up.

Acute knee trauma: value of a short dedicated extremity MR imaging examination for prediction of subsequent treatment (Article)

2005-01-01T00:00:00Z

PURPOSE: To assess the predictive value of a short magnetic resonance (MR) imaging examination, in addition to or instead of radiography, performed in patients with acute knee trauma to identify those who require additional treatment versus those who do not and can be discharged without further follow-up. MATERIALS AND METHODS: The randomized controlled trial and use of collected data for prediction modeling were approved by the institutional review board; informed consent was obtained. Patients with recent knee injury were included in the trial if radiography was ordered. They were randomized into a group undergoing only radiography and a group undergoing radiography plus immediate MR imaging. A 0.2-T dedicated extremity MR imager and four short pulse sequences were used. Univariable and multivariable logistic regression analysis was used to evaluate patient characteristics, trauma mechanism, and findings at radiography and MR imaging for their value in prediction of need for subsequent treatment within the 6-month follow-up. RESULTS: Data in 189 patients (123 male patients, 66 female patients; mean age, 33.4 years), 109 of whom underwent treatment after their initial visit, were analyzed. Age of 30 years or older, indirect trauma mechanism, radiographic results, and MR imaging results were significant predictors of need for treatment in univariable and multivariable analyses (P < .05). In the multivariable analysis, only abnormal MR imaging results were significantly predictive of need for treatment, and only when MR imaging replaced radiography (odds ratio, 2.61; 95% confidence interval: 1.12, 6.06). CONCLUSION: Implementation of a dedicated extremity MR imaging examination, in addition to or instead of radiography, performed in patients with traumatic knee injury improves prediction of the need for additional treatment but does not significantly aid in identification of patients who can be discharged without further follow-up. Value of a short MR imaging examination in the initial stage after knee trauma is limited.

Acute ankle trauma: value of a short dedicated extremity MR imaging examination in prediction of need for treatment (Article)

2005-01-01T00:00:00Z

PURPOSE: To assess predictive value of a short magnetic resonance (MR) imaging examination with or instead of radiography performed in patients with acute ankle trauma to identify those who require additional treatment versus those who do not and can be discharged without further follow-up. MATERIALS AND METHODS: Informed consent was obtained from all participating patients, and the institutional review board approved the randomized controlled trial and use of data to create prediction models. In a prospective controlled trial, 197 patients with recent ankle trauma (92 women, 105 men) were randomized into two groups: those who underwent radiography and those who underwent a combination of radiography and MR imaging. Data about side of injury, trauma mechanism, and results of radiography and MR imaging were collected. Additional treatment was necessary in 109 of 197 patients after their initial hospital visit. With univariable and multivariable regression analysis, four models were created for prediction of treatment. RESULTS: In univariable analysis, age (odds ratio [OR], 1.02; 95% confidence interval: 1.00, 1.04), radiographic results (OR, 7.92; 95% confidence interval: 3.17, 19.8), and positive or uncertain results in patients who underwent MR imaging versus patients who did not (OR, 2.42; 95% confidence interval: 1.25, 4.70) were predictive of treatment. In the multivariable analysis, positive or uncertain MR imaging results (OR, 2.61; 95% confidence interval: 1.28, 5.30) contributed significantly to prediction of subsequent treatment. Negative MR imaging results did not contribute significantly (OR, 0.66; 95% confidence interval: 0.27, 1.61). CONCLUSION: A limited MR imaging examination in initial evaluation of acute ankle injury with radiography has additional predictive value in identification of patients who need treatment but does not add significant information in identification of those who can be discharged without further follow-up. A limited MR imaging examination cannot replace radiography for prediction of need for additional treatment.

MR imaging of the menisci and cruciate ligaments: a systematic review. (Article)

2003-03-01T00:00:00Z

PURPOSE: To systematically review and synthesize published data on the diagnostic performance of magnetic resonance (MR) imaging of the menisci and cruciate ligaments and to assess the effect of study design characteristics and magnetic field strength on diagnostic performance. MATERIALS AND METHODS: Articles published between 1991 and 2000 were included if at least 30 patients were studied, arthroscopy was the reference standard, the magnetic field strength was reported, positivity criteria were defined, and the absolute numbers of true-positive, false-negative, true-negative, and false-positive results were available or derivable. Pooled weighted and summary receiver operating characteristic (ROC) analyses were performed for tears of both menisci and both cruciate ligaments separately and for the four lesions combined, by using random effects models. Differences were assessed according to lesion type. RESULTS: Twenty-nine of 120 retrieved articles were included. Pooled weighted sensitivity was higher for medial meniscal tears than that for lateral meniscal tears. However, pooled weighted specificity for the medial meniscus was lower than that for the lateral meniscus. In summary ROC analyses performed per lesion, various study design characteristics were found to influence diagnostic performance. Higher magnetic field strength significantly improved discriminatory power only for anterior cruciate ligament tears. When all lesions were combined in one overall summary ROC analysis, magnetic field strength was a significant but modest predictor of diagnostic performance. CONCLUSION: Diagnostic performance of MR imaging of the knee is different according to lesion type and is influenced by various study design characteristics. Higher magnetic field strength modestly improves diagnostic performance, but a significant effect was demonstrated only for anterior cruciate ligament tears.