Michael A. Woods

Knee Joint: Comprehensive Assessment with 3D Isotropic Resolution Fast Spin-Echo MR Imaging—Diagnostic Performance Compared with That of Conventional MR Imaging at 3.0 T

PURPOSE To determine whether a three-dimensional isotropic resolution fast spin-echo sequence (FSE-Cube) has similar diagnostic performance as a routine magnetic resonance (MR) imaging protocol for evaluating the cartilage, ligaments, menisci, and osseous structures of the knee joint in symptomatic patients at 3.0 T. MATERIALS AND METHODS This prospective, HIPAA-compliant, institutional review board-approved study was performed with a waiver of informed consent. FSE-Cube was added to the routine 3.0-T MR imaging protocol performed in 100 symptomatic patients (54 male patients with a median age of 32 years and 46 female patients with a median age of 33 years) who subsequently underwent arthroscopic knee surgery. All MR imaging studies were independently reviewed twice by two musculoskeletal radiologists. During the first review, the routine MR imaging protocol was used to detect cartilage lesions, ligament tears, meniscal tears, and bone marrow edema lesions. During the second review, FSE-Cube with multiplanar reformations was used to detect these joint abnormalities. With arthroscopic results as the reference standard, the sensitivity and specificity of FSE-Cube and the routine MR imaging protocol in the detection of cartilage lesions, anterior cruciate ligament tears, and meniscal tears were calculated. Permutation tests were used to compare sensitivity and specificity values. RESULTS FSE-Cube had significantly higher sensitivity (P = .039) but significantly lower specificity (P = .003) than the routine MR imaging protocol for detecting cartilage lesions. There were no significant differences (P = .183-.999) in sensitivity and specificity between FSE-Cube and the routine MR imaging protocol in the detection of anterior cruciate ligament tears, medial meniscal tears, or lateral meniscal tears. FSE-Cube depicted 96.2% of medial collateral ligament tears, 100% of lateral collateral ligament tears, and 85.3% of bone marrow edema lesions identified on images obtained with the routine MR imaging protocol. CONCLUSION FSE-Cube has similar diagnostic performance as a routine MR imaging protocol for detecting cartilage lesions, cruciate ligament tears, collateral ligament tears, meniscal tears, and bone marrow edema lesions within the knee joint at 3.0 T.

3.0-T Evaluation of Knee Cartilage by Using Three-Dimensional IDEAL GRASS Imaging: Comparison with Fast Spin-Echo Imaging

PURPOSE To compare the diagnostic performance of iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) gradient-recalled acquisition in steady-state (GRASS) imaging with a routine magnetic resonance (MR) imaging protocol for evaluating knee cartilage at 3.0 T in patients by using arthroscopy as the reference standard. MATERIALS AND METHODS This prospective Health Insurance Portability and Accountability Act-compliant study was performed with a waiver of informed consent from the institutional review board. IDEAL GRASS was added to routine 3.0-T knee MR protocol performed in 95 symptomatic patients (48 males, mean age, 34.5 years; 47 females, mean age, 35.5 years) who underwent subsequent arthroscopic surgery. Radiologists used the routine MR protocol during the first review and IDEAL GRASS during the second to grade each articular surface and to determine the presence of meniscal tears. By using arthroscopy as the reference standard, the sensitivity, specificity, and accuracy of both imaging methods for detecting cartilage lesions and meniscal tears were determined. RESULTS By using the z test to compare parameters between methods, the respective sensitivity, specificity, and accuracy for detecting all 192 cartilage lesions were 68.5%, 92.6%, and 84.5% for IDEAL GRASS and 66.1%, 92.9%, and 83.9% for the routine MR protocol. There was no significant difference (P = .34-.83) in parameters between methods for detecting cartilage lesions. The respective parameters for detecting 50 medial meniscal tears were 85.0%, 91.1%, and 87.9% for IDEAL GRASS and 94.0%, 90.0%, and 92.1% for the routine MR protocol. The parameters for detecting 31 lateral meniscal tears were 58.0%, 90.6%, and 80.0% for IDEAL GRASS and 80.1%, 91.4%, and 87.9% for the routine MR protocol. The routine MR protocol had a significantly higher sensitivity for detecting medial meniscal tears (P = .04) and lateral meniscal tears (P = .01) and significantly higher accuracy for detecting lateral meniscal tears (P = .03) than IDEAL GRASS. CONCLUSION IDEAL GRASS has similar diagnostic performance as routine MR protocol for evaluating the articular cartilage of the knee in clinical patients at 3.0 T but has significantly lower sensitivity and accuracy for detecting meniscal tears.

Clinical Usefulness of Adding 3D Cartilage Imaging Sequences to a Routine Knee MR Protocol

OBJECTIVE The objective of our study was to determine whether 3D sequences can improve the diagnostic performance of a routine MR protocol for detecting cartilage lesions within the knee joint at 3 T. SUBJECTS AND METHODS An iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) spoiled gradient-recalled echo (SPGR) sequence (n = 75 patients) or an IDEAL gradient-recalled acquisition in a steady state (GRASS) sequence (n = 75 patients) was added to routine 3-T knee MR protocol to examine 150 patients who subsequently underwent arthroscopic knee surgery. Each articular surface of the knee joint was graded at arthroscopy. All MR examinations were independently reviewed twice by two musculoskeletal radiologists. During the first review, the routine MR protocol was used alone to grade each articular surface of the knee joint; during the second review, the routine MR protocol was used with IDEAL-SPGR or IDEAL-GRASS. Using arthroscopy as the reference standard, the sensitivity and specificity for detecting cartilage lesions and the proportion of correctly graded cartilage lesions were determined for the routine MR protocol alone and for the routine MR protocol with IDEAL-SPGR or IDEAL-GRASS. The McNemar test was used to compare sensitivity, specificity, and accuracy values and proportions of correctly graded cartilage lesions. RESULTS There was a statistically significant improvement in the specificity (p < 0.05) but not the sensitivity (p = 0.08-0.32) for detecting cartilage lesions when using the routine MR protocol with IDEAL-SPGR or IDEAL-GRASS. There was also a statistically significant (p < 0.05) improvement in the proportion of correctly graded cartilage lesions when using the routine MR protocol with IDEAL-SPGR or with IDEAL-GRASS. CONCLUSION Adding 3D sequences to a routine MR protocol improves the diagnostic performance for detecting cartilage lesions within the knee joint at 3 T.

Improved fat suppression using multipeak reconstruction for IDEAL chemical shift fat-water separation: Application with fast spin echo imaging

To evaluate and quantify improvements in the quality of fat suppression for fast spin‐echo imaging of the knee using multipeak fat spectral modeling and IDEAL fat‐water separation.

Arthroscopic Partial Meniscectomy: MR Imaging for Prediction of Outcome in Middle-Aged and Elderly Patients

PURPOSE To determine whether preoperative magnetic resonance (MR) imaging could help identify factors associated with poor clinical outcome after arthroscopic partial meniscectomy (APM) in middle-aged and elderly patients with meniscal tears. MATERIALS AND METHODS The prospective, institutional review board-approved, HIPAA-compliant study was performed with informed consent in 53 men and 47 women (average ages, 54.5 and 56.6 years, respectively). Patients underwent knee MR imaging before APM; clinical symptoms were evaluated preoperatively and 1 year postoperatively with International Knee Documentation Committee (IKDC) questionnaire. Overall severity of knee joint degeneration and severity of each feature of joint degeneration were assessed with Boston Leads Osteoarthritis Knee (BLOK) scoring system. Tear length was measured, and type of meniscal tear was classified. Spearman correlation coefficients and relative risks showed the relationship between clinical outcome after APM (difference between preoperative and postoperative IKDC scores) and severity of joint degeneration. RESULTS Seventy-four patients with isolated medial APM had a significant (P < .05) inverse correlation between clinical outcome and severity of cartilage loss and bone marrow edema in the medial femoral condyle and medial tibial plateau. Fifteen patients with isolated lateral APM had a significant (P < .05) inverse correlation between clinical outcome and severity of cartilage loss in the lateral femoral condyle and lateral tibial plateau and bone marrow edema in the lateral femoral condyle. One hundred patients with APM had a significant (P < .05) inverse correlation between clinical outcome and severity of meniscal extrusion, total BLOK score, and meniscal tear length. A significantly (P < .05) increased relative risk that a patient would not definitely improve after APM was observed if a meniscal root tear was present. CONCLUSION Poorer clinical outcome after APM was associated with greater severity of cartilage loss and bone marrow edema in the same compartment as the meniscal tear, greater severity of meniscal extrusion, greater overall severity of joint degeneration, a meniscal root tear, and a longer meniscal tear at preoperative MR imaging.

Magnetic resonance imaging findings in patients with fibular stress injuries

ObjectiveThe objective was to evaluate magnetic resonance imaging (MRI) findings in patients with fibular stress injuries.Materials and MethodsThe study group consisted of 20 patients with clinically diagnosed fibular stress injuries who were evaluated with MRI. Radiographs were performed in 14 of the 20 patients. The MRI examinations and radiographs were retrospectively reviewed in consensus by two musculoskeletal radiologists.ResultsAll 20 patients with clinically diagnosed fibular stress injuries had periosteal edema and bone marrow edema within the fibula on MRI. The periosteal reaction and bone marrow edema were present within the distal fibula in 14 patients, the middle fibula in 1 patient, and the proximal fibula in 5 patients. The periosteal reaction was located on the anterior cortex in 1 patient, the posterior cortex in 4 patients, the lateral cortex in 11 patients, and circumferentially distributed throughout the cortex in 4 patients. Nine patients had abnormal T1 and T2 signal intensity within the fibular cortex. Initial and follow-up radiographs showed periosteal reaction in 15% and 50% of patients with fibular stress injuries respectively.ConclusionsThe majority of fibular stress injuries involve the lateral cortex of the distal fibula.

The cost effectiveness and utility of a “quick MRI” for the evaluation of intra-abdominal abscess after acute appendicitis in the pediatric patient population

INTRODUCTION Contrast-enhanced CT remains the first-line imaging for evaluating postoperative abscess (POA) after appendicitis. Given concerns of ionizing radiation use in children, we began utilizing quick MRI to evaluate POA and summarize our findings in this study. MATERIALS AND METHODS Children imaged with quick MRI from 2015 to 2017 were compared to children evaluated with CT from 2012 to 2014 using an age and weight matched case-control model. Radiation exposure, size and number of abscesses, length of exam, drain placement, and patient outcomes were compared. RESULTS There was no difference in age or weight (p>0.60) between children evaluated with quick MRI (n=16) and CT (n=16). Mean imaging time was longer (18.2±8.5min) for MRI (p<0.001), but there was no difference in time from imaging order to drain placement (p=0.969). No children required sedation or had non-diagnostic imaging. There were no differences in abscess volume (p=0.346) or drain placement (p=0.332). Thirty-day follow-up showed no difference in readmissions (p=0.551) and no missed abscesses. Quick MRI reduced imaging charges to

Clinical and Magnetic Resonance Outcomes in a Study of Prolotherapy for Knee Osteoarthritis: Evidence for a Potential Mechanism of Action

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Evaluation of the menisci of the knee joint using three-dimensional isotropic resolution fast spin-echo imaging: diagnostic performance in 250 patients with surgical correlation

5650 with CT. CONCLUSION Quick MRI demonstrated equivalent outcomes to CT in terms of POA detection, drain placement, and 30-day complications suggesting that MRI provides an equally effective, less expensive, and non-radiation modality for the identification of POA. TYPE OF STUDY Retrospective Case-Control Study. LEVEL OF EVIDENCE Level III.

Association between disease-specific quality-of-life and magnetic resonance imaging outcomes in a clinical trial of prolotherapy for knee osteoarthritis

weakness was noted in right-sided hip abduction, foot inversion, plantarflexion, and toe extension. Right medial ankle and foot arch were atrophied. Linear hyperpigmentation with associated induration was present from the medial groin down to the medial foot arch and the first toe. Setting: Sports Medicine Clinic. Results or Clinical Course: Right foot MRI revealed mild medial muscle atrophy and edema. Bilateral thigh MRI was normal. EMG study showed no foot muscle denervation. ANA and doublestranded DNA antibodies were positive. Dermatology was consulted, and a right medial thigh skin biopsy showed histopathologic evidence of morphea. Discussion: Morphea is a self-limited, localized scleroderma characterized by excessive collagen deposition, leading to dermal and subcutaneous tissue thickening. Considerable morbidity develops from growth interference, joint contractions, limb length discrepancy, and prominent atrophy. Therapy aims to reduce inflammation in early disease. Limited disease can be managed with topical or phototherapy, but disabling linear morphea requires more aggressive therapy with methotrexate, corticosteroids, or TNF-alpha inhibitors. By initiating TNF-alpha therapy for CD, our patient was unknowingly also treating undiagnosed linear morphea. Although this arrested disease progression, years of delayed diagnosis had already resulted in chronic disability. Conclusions: This case shows the importance of considering morphea in the differential diagnosis of a patient with focal atrophy, stiffness, and pain with abnormal skin findings, as earlier treatment may have altered her functional outcome.