Diagnostic performance of 3D TSE MRI versus 2D TSE MRI of the knee at 1.5 T, with prompt arthroscopic correlation, in the detection of meniscal and cruciate ligament tears

Single-Plane 3-Dimensional Isotropic Spin-Echo Magnetic Resonance Imaging Reconstructions of Shoulder Exhibit Superior Correlation to Surgical Findings Than 2-Dimensional Dixon Multiplanar Magnetic Resonance Imaging

OBJECTIVE

The aim of the study is to evaluate concordance of multiplanar 2-dimensional magnetic resonance imaging (2D-MRI) versus 3D isotropic MRI for rotator cuff and labral tears with the reference standard of arthroscopic surgical findings.

METHODS

It was an institutional review board-approved retrospective single-center study of consecutive preoperative patients with isotropic 3D-MRI on 3-Tesla scanners, multiplanar 2D-MRI, and shoulder arthroscopy. Scapular plane-oriented contiguous multiplanar reconstructions of 3D-images were evaluated by 2 experienced fellowship-trained musculoskeletal radiologists. Variables included the following: labral tear presence and rotator-cuff tear Ellman grade, thickness, and width. Sensitivities (Sen) and specificities (Spe) were calculated for binary variables. Mean squared errors (MSE) were calculated for ordinal variables. Lower MSE indicated higher concordance.

RESULTS

Seventy-two patients (43 female) with a mean age of 50.75 ± 9.76 years were evaluated. For infraspinatus-tear presence, 3D-MRI showed higher sensitivity (0.96) and specificity (0.68) than 2D-MRI (Sen = 0.85, Spe = 0.32) ( Psen = 0.005, Pspe = 0.002). For subscapularis-tear presence, 3D-MRI showed higher sensitivity (0.94) and specificity (0.73) compared with 2D-MRI (Sen = 0.83, Spe = 0.56) ( Psen = 0.02, Pspe = 0.04). For supraspinatus-tear presence, there was no significant difference between 3D-MRI (Sen =0.96, Spe = 0.67) compared with 2D-MRI (Sen = 0.98, Spe = 0.83) ( Psen = 0.43, Pspe = 0.63). For infraspinatus-tear thickness, 3D-MRI showed lower MSE (0.35) compared with 2D-MRI MSE (0.82) ( P = 0.01). For subscapularis-tear thickness, 3D-MRI had lower MSE (0.31) compared with 2D-MRI MSE (0.51) ( P = 0.007). However, no difference noted for supraspinatus-tear thickness when comparing 3D-MRI MSE (0.39) and 2D-MRI MSE (0.51) ( P = 0.49). For labral-tear presence, 3D-MRI had a lower MSE (0.20) compared with 2D-MRI MSE (0.57) ( P < 0.001).

CONCLUSIONS

Three-dimensional MRI of the shoulder is time efficient with a shorter acquisition time and exhibits comparable with superior correlation to surgical findings than 2D-MRI for detection of labral tears and some rotator cuff tears. Three-dimensional MRI may be used in place of traditional 2D-MRI in detection of soft-tissue shoulder injury in centers equipped to do so.

A new modified MR dual precision positioning of thin-slice oblique sagittal fat suppression proton density weighted imaging: its diagnostic accuracy in anterior cruciate ligament injury

To evaluate the diagnostic accuracy of a new modified MR dual precision positioning of thin-slice oblique sagittal fat suppression proton density-weighted imaging (DPP-TSO-Sag-FS-PDWI) sequence in detecting ACL injuries and its grades compared to standard sequences using arthroscopy as the standard reference. 42 patients enrolled in this retrospective study received the 1.5-T MRI with standard sequences and the new modified DPP-TSO-Sag-FS-PDWI sequence, and their arthroscopy results was recorded. The Mc Nemer-Bowker and weighted Kappa was performed to compare the consistency of MRI diagnosis with arthroscopic results. Finally, the diagnostic accuracy was calculated based on the true positive, true negative, false negative and false positive values. The diagnostic consistency of the DPP-TSO-Sag-FS-PDWI were higher than standard sequences for both reader 1 (K = 0.876 vs. 0.620) and reader 2 (K = 0.833 vs. 0.683) with good diagnostic repeatability (K = 0.794 vs. 0.598). Furthermore, the DPP-TSO-Sag-FS-PDWI can classify and diagnose three grades of ACL injury [the sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value were more than 84%], especially for grade II injury as the PPV was superior for reader 1 (92.3% vs. 53.9%) and reader 2 (84.6% vs. 69.2%). The new modified DPP-TSO-Sag-FS-PDWI sequence can display the ACL injury on one or continuous levels by maximizing the acquisition of complete ligament shape and true anatomical images, and excluding the influence of anatomical differences between individuals. It can improve the diagnostic accuracy with good repeatability and classify three grades of the ACL injury.

2D versus 3D MRI of osteoarthritis in clinical practice and research

Accurately detecting and characterizing articular cartilage defects is critical in assessing patients with osteoarthritis. While radiography is the first-line imaging modality, magnetic resonance imaging (MRI) is the most accurate for the noninvasive assessment of articular cartilage. Multiple semiquantitative grading systems for cartilage lesions in MRI were developed. The Outerbridge and modified Noyes grading systems are commonly used in clinical practice and for research. Other useful grading systems were developed for research, many of which are joint-specific. Both two-dimensional (2D) and three-dimensional (3D) pulse sequences are used to assess cartilage morphology and biochemical composition. MRI techniques for morphological assessment of articular cartilage can be categorized into 2D and 3D FSE/TSE spin-echo and gradient-recalled echo sequences. T2 mapping is most commonly used to qualitatively assess articular cartilage microstructural composition and integrity, extracellular matrix components, and water content. Quantitative techniques may be able to label articular cartilage alterations before morphological defects are visible. Accurate detection and characterization of shallow low-grade partial and small articular cartilage defects are the most challenging for any technique, but where high spatial resolution 3D MRI techniques perform best. This review article provides a practical overview of commonly used 2D and 3D MRI techniques for articular cartilage assessments in osteoarthritis.

Transepicondylar distance measured on MRI can predict the length of the graft required for different anterior cruciate ligament reconstruction (ACLR) techniques useful for revision surgery

Background

The aim of this study is to find a correlation between linear measurements and the graft length required for different anterior cruciate ligament (ACL) revision techniques, to extract formulas to predict required graft length during the preoperative planning.

Methods

At time 0 and 30 days later, two observers measured eight linear distances on standard 2D knee magnetic resonance imaging (MRI), and nine curved distances on 3D MRI sequences, corresponding to different techniques for ACL revision, anatomic anterolateral ligament (ALL) reconstruction, and lateral extrarticular tenodesis (LET). Intra- and interobserver reliability was tested for 2D and 3D measurements. The correlation between 2D and 3D measurements was tested. The 2D measurements with highest repeatability and reproducibility, and with strongest correlation with 3D measurements were used to extract formulas to calculate the graft length from 2D values.

Results

Fifty MRIs acquired with both 2D and 3D sequences were used. The intra- and interobserver reliability of linear 2D measurement was high, with the transepicondylar distance (TD) showing the highest reproducibility and repeatability. The intra- and interobserver reliability of 3D measurements was lower than 2D, but acceptable for all measurements except for ALL reconstruction. The TD showed the strongest correlation with 3D measurements. The formulas extracted to calculate the graft length from the TD proved to be accurate.

Conclusion

Accurate formulas were created to calculate the graft length needed for different ACL revision techniques and ALL reconstruction/LET techniques from TD. These formulas can be used during preoperative planning of ACL revision cases.

Meniscal Root Tears: An Update Focused on Preoperative and Postoperative MRI Findings

Meniscal root tears represent radial tears or avulsions of the meniscal cartilage at the tibial attachment site that profoundly affect meniscal biomechanics and kinematics. Meniscal root tears have the functional effect of a total meniscectomy and can lead to rapid degenerative change with development of early knee osteoarthritis (OA). A growing range of arthroscopic surgical techniques have been developed to repair meniscal root tears with the aim of restoring joint kinematics and contact pressures and delaying the development of OA. With increased understanding of the anatomy and biomechanics of the meniscal root, meniscal root injury repair has become the treatment of choice in knees with nonadvanced OA. This article reviews the anatomy and biomechanics of the meniscal roots, clinical and imaging diagnostic criteria of meniscal root tears, correlation between arthroscopy and MRI in the diagnosis and classification of meniscal root tears, and expected and abnormal MRI findings after meniscal root repair. Familiarity with MRI signs and classifications of meniscal root tears, as well as with root repair surgical techniques, can aid radiologists in correctly reporting preoperative and postoperative MRI findings.

Transepicondylar Distance Can Predict Graft and Tunnel Length for Different Pediatric Anterior Cruciate Ligament Reconstruction Techniques: A Magnetic Resonance Imaging Study

PURPOSE

To find a correlation and mathematical formulas between a linear 2-dimensional (2D) magnetic resonance imaging (MRI) measurement around the knee and the length of the grafts and tunnels required for both all-inside-all-epiphyseal and Kocher-Micheli pediatric anterior cruciate ligament (ACL) reconstruction techniques.

METHODS

At time 0 and 30 days after, 2 observers measured: (1) on standard 2D knee MRI, 7 linear distances, representing morphologic measurements, such as transepicondylar distance (TD), and (2) on 3-dimensional (3D) MRI, 5 curved distances, corresponding to Kocher-Micheli and all-epiphyseal ACL reconstruction techniques. Intra- and interobserver reliability was tested for all measurements. The correlation between 2D and 3D measurements was tested. The 2D measurement with highest repeatability and reproducibility and with strongest correlation with 3D measurements was used to extract formulas to calculate the tunnel and graft length for the 2 techniques.

RESULTS

Seventy-six MRIs were used. The intra- and interobserver reliability of 2D measurement was high, with TD showing the highest reproducibility and repeatability. 3D measurements also showed good intra and inter-observer reliability. A linear correlation was found between 2D and 3D measurements, with TD showing the strongest correlation. TD was used to extract formulas to calculate graft or tunnel length for Kocher-Micheli and all-epiphyseal ACL reconstruction. All formulas were proven to be accurate. A reference chart was also created to be used in the surgical setting.

CONCLUSIONS

With specific formulas, TD can be used to calculate the length of the tunnels, intra-articular portion and graft length for an all-inside all-epiphyseal pediatric ACL reconstruction and the length of the iliotibial band required for the Kocher-Micheli technique.

CLINICAL RELEVANCE

The surgeon can use these formulas in pediatric ACL reconstruction preoperative planning, graft harvesting and tunnel drilling.

Is there a good agreement between MRI readers for Thaunat's classification in arthroscopically-proven meniscal ramp lesions?

OBJECTIVE

To describe and evaluate the reproducibility by MRI of an arthroscopically-based classification for meniscal ramp lesions. We hypothesize that MRI would present good interobserver and intraobserver reliability to evaluate meniscal ramp lesions.

MATERIALS AND METHODS

Twenty MRI of the knee with arthroscopically-proven meniscal ramp lesions were independently assessed by two skilled musculoskeletal radiologists and a third-year radiology resident. Reading was performed in a randomized and anonymous manner, in two steps, with a minimum of 1-month interval between each. Cohen's kappa coefficient statistic was used to analyze intra and interobserver reading agreement. Associate findings were also categorized.

RESULTS

From 20 subjects, 17 were male, with mean age of 35 years. MRI reading showed type IV ramp lesion as most prevalent with eight cases (37%), followed by type V - four (21%), type I - four (20%), type III - three, (16%) and type II - one (6%). Regarding ramp lesion types, intraobserver agreement was substantial for both skilled readers (Kappa = 0.72), and moderate for the less experienced reader (Kappa = 0.51); interobserver agreement was moderate. Results between most experienced readers were also analyzed in two categories: stable (types I and II) and unstable (types III, IV and V), also resulting in moderate agreement (Kappa = 0.54). Intraobserver agreement was substantial for both readers (Kappa = 0.68). The most common associate findings were joint effusion (85%), posteromedial capsular structures injury (60%), and medial meniscus extrusion (60%).

CONCLUSION

The arthroscopy classification for meniscal ramp lesions stability adapted for MRI has good reproducibility when applied by trained musculoskeletal radiologists.

Clinical utility of fat-suppressed 3-dimensional controlled aliasing in parallel imaging results in higher acceleration sampling perfection with application optimized contrast using different flip angle evolutions MRI of the knee in adults

OBJECTIVE

To compare htree-dimensional CAIPIRINHA SPACE and two-dimensional turbo spin echo (2D TSE) MRI in the diagnosis of knee pathology in symptomatic adult patients.

METHODS

From February to September in 2018, 120 patients who underwent a knee MRI using both 3D CAIPIRINHA SPACE and 2D TSE MRI were enrolled. The signal-to-noise ratios (SNRs) and contrast-to-noise ratio (CNR) of the 2D and 3D MRI were compared using a paired t-test. Two radiologists independently evaluated both 2D and 3D MRI images using scoring systems for the menisci, ligaments, and cartilage. Intermethod, inter- and intrareader agreements were determined using an intraclass correlation coefficient (ICC). The diagnostic performance of both methods was measured in 44 patients with arthroscopy.

RESULTS

The mean scan time of 3D CAIPIRINHA SPACE MRI (4' 43") was shorter than that of 2D TSE MRI (17' 27"). The mean SNR and CNR of 3D CAIPIRINHA SPACE was higher than those of 2D TSE MRI (mean difference, 3.97 of SNR and 1.58 of CNR; p < 0.001 and p = .038, respectively). Intermethod (ICC, 0.84-1.0) and inter-reader (ICC, 0.75-0.97), and intra-reader agreements (ICC, 0.87-1.0) were good or excellent. The diagnostic accuracy of 3D CAIPIRINHA SPACE sequence was equal for ligament (95.5%) and better for meniscal and cartilage evaluation (84.1% each), compared to 2D TSE MRI (79.5% each).

CONCLUSION

The fat-suppressed 3D CAIPIRINHA SPACE MRI maybe useful in clinical practice for the evaluation of the knee in place of the 2D conventional MRI protocol.

ADVANCES IN KNOWLEDGE

1. The 3D CAIPIRINHA SPACE MRI of the knee joint may be acceptable to be used in clinical practice showing comparable imaging quality compared to conventional 2D TSE MRI.2. Compared with arthroscopic findings as the gold-standard, the diagnostic performance of 3D CAIPIRINHA SPACE MRI was equal or better for knee joint evaluation than that of 2D TSE MRI, as well as with shorter scan time.

The usefulness of chemical-shift magnetic resonance imaging for the evaluation of osteoid osteoma

Objective

The purpose of this study was to determine whether chemical-shift magnetic resonance imaging (MRI) could be useful in the diagnosis of osteoid osteoma when clinical and radiological tumor features are inconclusive.

Materials and Methods

This retrospective study included 17 patients who underwent chemical-shift MRI for the evaluation of osteoid osteoma. For all patients, two musculoskeletal radiologists independently recorded signal intensities on in-phase and out-of-phase images in the nidus of the tumor, in abnormal-intensity bone marrow surrounding the lesion, and in normal-appearing bone marrow. For each region, relative signal intensity ratios were calculated by dividing out-of-phase by in-phase values. Relative ratios > 1 were considered indicative of neoplastic lesions. Statistical analysis was carried out to analyze the sample. Inter-observer and intra-observer agreement for each imaging method were assessed using intraclass correlation coefficients according to the Fleiss method and a value > 0.65 was considered to indicate substantial agreement.

Results

The mean relative signal intensity ratios were 1.2 (range, 0.9-1.4) for the nidus and 0.35 (range, 0.11-0.66) for the surrounding tissue; these values differed significantly from the relative signal-intensity ratios for normal-appearing bone marrow (p < 0.05).

Conclusion

Chemical-shift MRI is useful for the diagnosis and evaluation of osteoid osteoma.

MR arthrography of the hip: diagnostic performance and image quality of 3D-steady state free precession versus 2D turbo spin echo sequences

OBJECTIVE

To retrospectively compare the diagnostic performance of isotropic 3D steady-state free precession (3D-SSFP) sequences with 2D turbo spin-echo proton density-weighted fat-saturated (2D-TSE-PD fs) images in hip magnetic resonance arthrography; arthroscopy was a standard of reference.

METHODS

Eighty-one patients with suspected labral tears who underwent hip MR arthrography (3-T scanner) were included. 2D-TSE-PD fs sequences were acquired in three planes and a singular sagittal 3D-SSFP. Labral tears, cartilage pathology and bone marrow were independently assessed by two blinded radiologists using a 5-point Likert scale. Accuracy was determined in 39 patients using invasive arthroscopy.

RESULTS

Diagnostic confidence of labral and cartilaginous pathologies based on image quality was rated higher for 3D-SSFP (4.5 ± 0.8; 4.35 ± 0.7; p < 0.0001), but inferior for bone marrow pathology (3.9 ± 0.7; 4.0 ± 0.7; p < 0.0001). In the arthroscopy patients, similar sensitivity (85.9%) but higher specificity (74.4vs.42.9%) and higher positive and negative predictive values were found in 3D-SSFP of labral and cartilage pathologies.

CONCLUSIONS

3D-SSFP in hip magnetic resonance arthrography offers increased accuracy in detecting labral and cartilage pathologies compared with 2D-TSE-PD, while reducing the acquisition time. A drawback of 3D-SSFP was the inferior diagnostic confidence for bone marrow evaluation; thus, 3D-SSFP should be combined with conventional 2D-TSE sequences.

Magnetic resonance arthrography of the shoulder: a painful procedure?

Objective

To compare the pain expected to that effectively caused by magnetic resonance arthrography of the shoulder and, secondarily, to describe a simplified approach to the technique for articular access.

Materials and Methods

We prospectively evaluated 40 participants who used a visual analog scale and a simplified categorical scale to indicate the level of pain expected and that experienced after the procedure, comparing the two with the Wilcoxon matched-pairs test. We also determined gender-related differences in pain conditions using the Mann-Whitney U test. In addition, we described a modified technique involving radiographic localization and the use of standard puncture needles for articular access.

Results

Analysis of the visual analog scales showed that the pain experienced was less than had been expected, with median scores of 1.75 and 3.75, respectively (p < 0.001). The level of pain expected was higher among women than among men, with median scores of 8.0 and 3.0, respectively (p = 0.014), as was the level of pain experienced, with median scores of 3.0 and 1.5, respectively (p = 0.139). The overall categorical evaluation corroborated that difference (p = 0.03). Articular access with the modified technique was successful in all patients.

Conclusion

Magnetic resonance arthrography of the shoulder is less painful than patients expect. In addition, digital radiographic guidance combined with the use of standard puncture needles appears to improve the efficiency of the method.

Ischiofemoral impingement secondary to valgus intertrochanteric osteotomy: a case report

We report an unusual case of ischiofemoral impingement secondary to valgus intertrochanteric osteotomy. The osteotomy was performed for treatment of epiphysiolysis of the left femoral head.

The diagnostic accuracy of magnetic resonance imaging for anterior cruciate ligament injury in comparison to arthroscopy: a meta-analysis

We performed this meta-analysis to examine the diagnostic accuracy of MRI for the diagnosis of anterior cruciate ligament (ACL) injury in comparison to arthroscopy. We also compared the diagnostic accuracy of MRI with magnetic field intensities (MFI) greater than or equal to 1.5T with those below 1.5T, in addition to different MRI sequences. Studies relevant to the diagnosis of ACL injury by MRI and arthroscopy were analyzed. Computer and manual retrieval were carried out on studies published between January 1, 2006 and May 31, 2016. Twenty-one papers were included. Neither threshold nor non-threshold effects were present (p = 0.40, p = 0.06). The pooled sensitivity (SE), specificity (SP), positive likelihood ratio (LR+), negative likelihood ratio (LR−) and diagnostic odds ratio (DOR) with 95% confidence interval (CI) were 87% (84–90%), 90% (88–92%), 6.78 (4.87–9.44), 0.16 (0.13–0.20) and 44.70 (32.34–61.79), respectively. The area under the curve (AUC) was 0.93. The risk of publication bias was negligible (p = 0.75). In conclusion, examination by MRI is able to provide appreciable diagnostic performance. However, the principle, which states that the higher the MFI, the better the diagnostic accuracy, could not be verified. Additionally, conventional sequences (CSs) associated with proton density-weighted imaging (PDWI) are only slightly better than CSs alone, but not statistically different.

Diagnostic performance of magnetic resonance imaging in the assessment of periosteal reactions in bone sarcomas using conventional radiography as the reference

Objective:

To evaluate the performance of magnetic resonance imaging (MRI) in detecting periosteal reactions and to compare MRI and conventional radiography (CR) in terms of the classification of periosteal reactions.

Materials and Methods:

Retrospective study of 42 consecutive patients (mean age, 22 years; 20 men) with a confirmed diagnosis of osteosarcoma or Ewing's sarcoma, MRI and CR images having been acquired pretreatment. Three blinded radiologists detected periosteal reactions and evaluated each periosteal reaction subtype in CR and MRI images: Codman's triangle; laminated; and spiculated. The CR was used as a benchmark to calculate the diagnostic performance. We used the kappa coefficient to assess interobserver reproducibility. A two-tailed Fisher's exact test was used in order to assess contingency between CR and MRI classifications.

Results:

In the detection of periosteal reactions, MRI showed high specificity, a high negative predictive value, and low-to-moderate sensitivity. For CR and for MRI, the interobserver agreement for periosteal reaction was almost perfect, whereas, for the classification of different subtypes of periosteal reaction, it was higher for the Codman's triangle subtype and lower for the spiculated subtype. There was no significant difference between MRI and CR in terms of the classifications (p < 0.05).

Conclusion:

We found no difference between MRI and CR in terms of their ability to classify periosteal reactions. MRI showed high specificity and almost perfect interobserver agreement for the detection of periosteal reactions. The interobserver agreement was variable for the different subtypes of periosteal reaction.