MR Arthrography of the Hip: Comparison of IDEAL-SPGR Volume Sequence to Standard MR Sequences in the Detection and Grading of Cartilage Lesions

Department of Radiology, University of Wisconsin School of Medicine and Public Health, 600 Highland Ave, E3/311, Madison, WI 53792, USA.
Radiology (Impact Factor: 6.87). 09/2011; 261(3):863-71. DOI: 10.1148/radiol.11110001
Source: PubMed
To compare the diagnostic performance of iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL)-spoiled gradient-recalled echo (SPGR) with that of standard magnetic resonance (MR) arthrography sequences for detecting and grading cartilage lesions within the hip joint during MR arthrography.
Following institutional review board approval, 67 consecutive hip MR arthrograms were retrospectively reviewed independently by three musculoskeletal radiologists and one musculoskeletal fellow. IDEAL-SPGR images and the two-dimensional images, the latter from the routine MR arthrography protocol, were evaluated at separate sittings to grade each articular surface of the hip joint. By using arthroscopy as the reference standard, the sensitivity and specificity of the two techniques for detecting and grading cartilage lesions were determined. The McNemar test was used to compare diagnostic performance. Interreader agreement was calculated using Fleiss κ values.
For all readers and surfaces combined, the sensitivity and specificity for detecting cartilage lesions was 74% and 77%, respectively, for IDEAL-SPGR and 70% and 84%, respectively, for the routine MR arthrography protocol. IDEAL-SPGR had similar sensitivity (P = .12) to and significantly lower specificity (P < .001) than the routine MR arthrography protocol for depicting cartilage lesions. When analyzing the differences in sensitivity and specificity by reader, the two readers who had experience with IDEAL-SPGR had no significant difference in sensitivity and specificity for detecting cartilage lesions between the two sequences. For all readers and surfaces combined, IDEAL-SPGR had a higher accuracy in correctly grading cartilage lesion (P = .012-.013). Interobserver agreement for detecting cartilage lesions did not differ between the two techniques.
IDEAL-SPGR had similar sensitivity and significantly lower specificity for detecting cartilage lesions and higher accuracy for grading cartilage lesions than did a routine MR arthrography protocol; the lower specificity of IDEAL-SPGR for detecting cartilage lesions was not seen in experienced readers.

Full-text preview

Available from:
  • Source
    [Show abstract] [Hide abstract] ABSTRACT: Background: Accurate, reproducible, and noninvasive assessment of hip cartilage is clinically relevant and provides a means by which to assess the suitability of candidates for arthroscopic or open surgical procedures and the response to such interventions over time. Given the relatively thin cartilage of the hip and the complex spherical anatomy, however, accurately assessing the cartilage poses a challenge for traditional MRI techniques. Questions/purposes: We assessed the current status of imaging articular cartilage of the hip through a comprehensive review of recent literature. Methods: We performed a literature review using PubMed. Topics included quantitative MRI, imaging of the hip cartilage and labrum, femoroacetabular impingement syndrome, and osteoarthritis of the hip. WHERE ARE WE NOW?: With the use of high in-plane and through-plane resolution, reproducible assessment of hip cartilage and labrum is clinically feasible. More recent quantitative MR techniques also allow for noninvasive assessment of collagen orientation and proteoglycan content in articular cartilage, thus providing insight into early matrix degeneration. These techniques can be applied to cohorts at risk for osteoarthritis, helping to predict cartilage degeneration before symptoms progress and osteoarthritic changes are visible on radiographs. WHERE DO WE NEED TO GO?: Prospective longitudinal data registries are necessary for developing predictive models of osteoarthritis and subsequent joint failure to assess the results of surgical intervention and predict the timing of arthroplasty. HOW DO WE GET THERE?: By establishing more hip cartilage registries, a correlation can be made between subjective measures and morphologic MRI to assess the cartilage, labrum, bone, and synovial lining of the hip.
    Preview · Article · Jun 2012 · Clinical Orthopaedics and Related Research
  • Source
    [Show abstract] [Hide abstract] ABSTRACT: Objective: This article provides a review of femoroacetabular impingement (FAI) and the role MRI is attempting to fulfill in this complex and sometimes controversial condition. A perspective on the current status and on the advantages of 1.5-T MR arthrography is presented, and its usefulness in this setting is compared with the potential of nonarthrographic 3-T MRI. Conclusion: With its increasing availability, 3-T MRI has the potential to provide routine, less invasive assessment of the hip for FAI.
    Full-text · Article · Sep 2012 · American Journal of Roentgenology
  • [Show abstract] [Hide abstract] ABSTRACT: Brain iron deposits have been demonstrated to be an important indicator in the pathophysiology of neurodegenerative processes. Hence, it is crucial to study the basic characteristics of ferric ion by using a noninvasive imaging modality, such as magnetic resonance imaging (MRI). Spoiled gradient recalled echo (SPGR) is one of the rapid MRI scanning pulse sequences and has been widely used in clinical diagnosis. There are three important scanning parameters, i.e., repetition time (TR), echo time (TE), and flip angle (FA), which will affect the SPGR MR signal intensity (SI) and contrast of investigated tissues and organs. The purpose of this study is to investigate the variability of SPGR MR SIs of ferric iron solutions with various concentrations by changing the TR, TE, and FA using a 1.5-T clinical whole body scanner. It was found that the optimal flip angle, i.e., the Ernst angle, increased with the concentration of ferric ions. The SI increased rapidly at smaller TRs and then rose slowly as the TR became larger. The SI was also found to be smaller for longer TE. Furthermore, there was better linearity between the MR, SI, and ferric iron concentration for the smaller TE, smaller TR, and larger FA.
    No preview · Article · Mar 2013 · Biomarkers and Genomic Medicine
Show more