Oblique Coronal MR Imaging Research Articles

Evaluation of The Technical Value of Oblique Coronal MR Imaging to Diagnose Anterior Cruciate Ligament Tear

Evaluation of The Technical Value of Oblique Coronal MR Imaging to Diagnose Anterior Cruciate Ligament Tear

Femoral Trochlear Groove Morphometry Assessed on Oblique Coronal MR Images.

The objective of our study as to assess several indexes relevant to patellofemoral instability (PFI) associated with femoral trochlear dysplasia as measured on oblique coronal MR images at three standardized reference levels. A total of 30 knee MRI examinations were selected as the study group of PFI patients. Sixty knee MRI examinations were included as a control group. MRI protocols included sagittal T2-weighted, axial proton density-weighted, and oblique coronal T2-weighted imaging. On a midline sagittal image, the following three levels of the femoral trochlear groove cartilage were determined: level 1 (one-fourth level of the trochlear groove in the midsagittal plane), level 2 (one-half level of the trochlear groove in the midsagittal plane), and level 3 (three-fourths level of the trochlear groove in the midsagittal plane). Three-level axial and oblique coronal images were selected using the sagittal image as a scout. Femoral trochlear indexes including the sulcus angle, sulcus depth, facet length, and trochlear groove area were measured on the axial and oblique coronal images. Most indexes showed significant differences between the PFI and control groups in the axial and oblique coronal planes at all three levels (p < 0.05). Almost all indexes measured on the oblique coronal plane images were significantly different from those measured on the axial plane images (p < 0.05). Oblique coronal images showed little variability in the sulcus angle among the three levels in contrast to a marked decrease in the angle from the proximal to distal level on axial images. Femoral trochlear indexes measured on oblique coronal knee MR images can be used to assess femoral trochlear dysplasia. Oblique coronal images showed less morphologic distortion of the distal femoral trochlear groove than axial images.

Usefulness of oblique coronal and sagittal MR images of the knee after double-bundle and selective anterior cruciate ligament reconstructions

The use of double-bundle and selective-bundle anterior cruciate ligament (ACL) reconstruction is increasing. Few studies have been conducted to determine the diagnostic efficacy of additional oblique views of knee magnetic resonance imaging (MRI) for grading ACL graft injury for double-bundle and selective-bundle ACL reconstructions. To evaluate the diagnostic value of combining oblique coronal and sagittal imaging with orthogonal views for diagnosis of ACL graft failure after double-bundle or selective-bundle ACL reconstruction. This retrospective study included 64 patients who underwent double-bundle or selective-bundle ACL reconstruction surgery and received oblique coronal and oblique sagittal MRI of the knee. Subjective scoring of the images was performed by two radiologists who assessed the possibility of ACL graft failure based on full length view, full width view, and margin sharpness according to a 4-point scale. Diagnostic performance for ACL graft failure based on orthogonal views alone, ACL views alone, and orthogonal views with additional ACL views was evaluated by calculating the sensitivity, specificity, and accuracy. The full length scores and total scores on ACL views were significantly higher than those of orthogonal views. The specificities and accuracies of diagnoses were highest for a combination of orthogonal, ACL sagittal, and ACL coronal views. After double-bundle or selective-bundle ACL reconstruction, oblique sagittal and coronal images of the ACL provide better anatomic evaluation of the ACL than orthogonal views and specificity and accuracy of diagnoses were improved when oblique views were combined.

Can a high acromion index predict rotator cuff tears?

The purpose of this study was to identify the relationship between an acromion index (AI) and the size of a rotator cuff tear. The hypothesis of our study was that an AI will be higher in patients with a full-thickness tear than in patients with a partial-thickness articular-side tear, and that it can be used as a predictor for the size of a rotator cuff tear. We included 284 patients who had been diagnosed with rotator cuff tears and had undergone arthroscopic rotator cuff repair at our institute. All patients were divided into five distinct groups (partial-thickness articular side tear, and four subgroups of full-thickness tears) depending on the size of the rotator cuff tear on arthroscopy. In each patient, an AI was measured on the pre-operative oblique coronal MR images and then analysed to determine the difference between groups. There were statistically significant differences between the partial-thickness articular side rotator cuff tear and large-to-massive rotator cuff tear groups (p < 0.01), and the mean value of an AI was highest in the large-sized full-thickness tear group. The AI of the partial-thickness articular-side rotator cuff tear group was statistically different from the large-to-massive rotator cuff tear groups. The AI can be a predictor which can differentiate a partial-thickness articular-side tear and a large-to-massive rotator cuff tear pre-operatively. However the AI could not provide useful guidance on predicting the differences in tear size in full-thickness tear patients. We suggest that a high AI can be one of the associated factors for progression to large-to-massive rotator cuff tears in a rotator cuff disease.

Contribution of thin slice (1 mm) oblique coronal proton density-weighted MR images for assessment of anteromedial and posterolateral bundle damage in anterior cruciate ligament injuries

PurposeTo evaluate the diagnostic efficacy of using additional oblique coronal 1mm proton density-weighted (PDW) MR imaging of the knee for detection and grading anterior cruciate ligament (ACL), anteromedial bundle (AMB) and posterolateral bundle (PLB) injuries. Materials and methodsWe prospectively assessed preoperative MR images of 50 patients (36 men, 14 women; age range, 18–62 years). First, we compared the diagnostic performance of routine sagittal (3mm) and additional oblique coronal images (1mm) for ACL tears. Then, we compared the tear types (AMB or PLB) and grade presumed from oblique coronal MR imaging with arthroscopy. ResultsArthroscopy revealed ACL tear in 24 (48%) patients. There was significant difference between sagittal images and arthroscopy results for ACL tear recognition (p<0.001). No significant difference was detected for oblique coronal images when compared with arthroscopy results (p=0.180). Sensitivity and specificity values for ACL tear diagnosis were 37.04% and 95.65% for sagittal images; 74.07% and 91.30% for oblique coronal images. There was no significant difference between arthroscopy and oblique coronal MR images in grading AMB and PLB injuries (p>0.05). ConclusionAddition of thin slice oblique coronal images to conventional sequences could better contribute to better verifying the presence of ACL tear and in determining its grade.

Grading Anterior Cruciate Ligament Graft Injury after Ligament Reconstruction Surgery: Diagnostic Efficacy of Oblique Coronal MR Imaging of the Knee

ObjectiveThe purpose of this study was to evaluate the diagnostic efficacy of using additional oblique coronal MRI of the knee for grading anterior cruciate ligament (ACL) graft injury after ligament reconstruction surgery.Materials and MethodsWe retrospectively reviewed 51 consecutive MR knee examinations of 48 patients who underwent both ACL reconstruction and follow-up arthroscopy. The MR examinations included the orthogonal axial, sagittal, coronal images and the oblique coronal T2-weighted images, which were oriented in parallel with the course of the femoral intercondylar roof. Two radiologists independently evaluated the status of the ACL grafts with using the routine knee MRI and then with adding the oblique coronal imaging. The severity of ACL graft injury was graded using a 3-point system from MR images as intact, partial tear or complete tear, and the results were compared with the arthroscopic results. Weighted kappa statistics were used to analyze the diagnostic accuracies of the knee MRI with and without the additional oblique coronal imaging. For each evaluation, the observers reported a confidence level for grading the ACL graft injuries in the two imaging groups.ResultsThe weighted kappa values according to the routine knee MRI were 0.555 (reader 1) and 0.515 (reader 2). The inclusion of additional oblique coronal imaging increased the weighted kappa values to 0.666 (reader 1) and 0.611 (reader 2). The mean confidence levels by each reader were significantly higher (p < 0.01, paired t-test) with the additional oblique coronal imaging than by using the routine knee MRI alone.ConclusionThe additional use of oblique coronal MRI of the knee improves both the diagnostic accuracy and confidence for grading ACL graft injury.

Characteristics of hippocampal volumes in healthy Chinese from MRI

Background/objectives: The volume of hippocampus has been associated with a number of disorders and would be helpful in clinical and research practice. This study provided the normal data of hippocampal volumes in a healthy Chinese sample and assessed the possible effects of age, gender and side on it.Methods: Sixty-one normal participants with a broad age span from 6 to 82 years were enrolled in the study. The hippocampal volumes of them were obtained from oblique coronal MR images using inversion recovery (IR) sequence and normalized to adjust intersubject variation in head size.Results: The corrected volume in the right side of hippocampus was 2.204–2.944 cm3, and 2.068–2.700 cm3 in the left. There were no statistically significant differences among different age and gender groups (p>0.05). The volume of right hippocampus was larger than that of the left side (p<0.001).Conclusions: We presented the volume range of hippocampus in healthy Chinese on MRI in this study. No age and gender effects were found on hippocampal volumes. Side-to-side asymmetry was obtained by statistical analysis.

Oblique Coronal MRI in the Evaluation of Bony Stenosis of the Cervical Foramina: Objectiveness and Correlation with Radiograph

Purpose: To determine the utility of oblique coronal MR (OMR) imaging in the evaluation of bony foraminal narrowing of the cervical spine by comparison of its findings with those of combined axial and sagittal MR (CMR) imaging and correlation with the findings of oblique radiography. Materials and Methods: One hundred and eight cervical neural foramina in 18 patients formed the basis of this study. Three radiologists working in a blind fashion independently graded the degree of bony narrowing of the foramina seen on OMR and CMR images and on oblique radiographs (0=none, 1=stenosis below 25% of AP dimension, 2=stenosis exceeding 25% of AP dimension). Inter-observer variance was measured for each modality, and for each of these and for each foramen, consensus was reached as to whether of CMR or OMR showed better correlation with radiographs. Results: Inter-observer variance in OMR was less (kappa=0.88) than in CMR (kappa=0.41). Correlation between the findings of OMR and radiography was also better (kappa=0.63) than between those of CMR and radiography (kappa=0.41). Conclusion: OMR can be a useful supplement in evaluating foraminal stenosis, especially when oblique radiographs and CMR images show discrepancies.

MRI Differential Diagnosis of Complete and Partial Tears of the Anterior Cruciate Ligament of the Knee: The Usefulness of Oblique Coronal T2-Weighted Image

Purpose: To assess the usefulness of T2-weighted oblique coronal MR imaging (T2OCI) in the differential diagnosis of complete and partial tears of the anterior cruciate ligament (ACL) of the knee. Materials and Methods: Thirty-three patients with ACL tear (16 complete and 17 partial tears), comfirmed by arthroscopy, were included in this study. Conventional MR imaging and T2OCI were performed, and the findings were retrospectively reviewed by two radiologists in terms of continuity, shape, axis and internal signal intensity of the ligament. Each finding was tested if there were stastistically significant differences in its prevalence between partial and complete tears. The diagnostic accuracy of T2OCI and conventional MR imaging in the detection of partial and complete tears of the ACL were compared. Results: Conventional MR imaging revealed no statistically significant finding for differential diagnosis of complete and partial ACL tears. The reliable and statistically significant (p

Evaluation of the Size of Rotator Cuff Tear on Oblique Coronal MR Imaging

Evaluation of the Size of Rotator Cuff Tear on Oblique Coronal MR Imaging

Superior labrum and labral-bicipital complex: MR imaging with pathologic-anatomic and histologic correlation.

The purpose of this study was to analyze the anatomic relationship between the superior labrum, the superior glenoid rim, the superior glenohumeral ligament, and the long head of the biceps tendon. Seventeen cadaveric shoulder specimens underwent axial, oblique coronal, and oblique sagittal MR imaging on a 1.5-T imager. Unenhanced proton density- and T2-weighted spin-echo images with and without fat suppression, and T1-weighted fat-suppressed spin-echo images after intraarticular injection of gadolinium, were obtained of each specimen. The shoulders were then frozen and sectioned into 4-mm-thick slices, either transversely or oblique coronally. After gross anatomic correlation, histologic analysis was performed on 32 sections. A sublabral recess was present in 12 (71%) of 17 shoulders. MR arthrography was significantly better at showing the sublabral recess than was unenhanced MR imaging. Histologically, the synovial recess in all cases was covered by synovial lining cells. Intralabral altered histologic patterns were found in 20 (63%) of 32 labral sections. In addition to signs of degeneration, five sections of two specimens showed proliferating fibroblasts and vessels, as well as fibrosis, suggesting trauma. The presence or absence of altered intralabral histologic patterns was better assessed with T1-weighted fat-suppressed arthrograms than with unenhanced MR images. We found a close association grossly and histologically between the superior labrum and the biceps tendon. The attachment of the superior glenoid labrum to the glenoid rim shows great variability. In MR imaging, an overlap appears to exist between physiologic recesses of the superior labrum and a type 2 superior labrum anterior-posterior lesion. T1-weighted fat-suppressed MR arthrograms provided the best view of the superior labrum and the labral-bicipital complex.

Usefulness of T2-weighted Oblique Coronal MR Imaging In Anterior Cruciate Ligament Injury

Usefulness of T2-weighted Oblique Coronal MR Imaging In Anterior Cruciate Ligament Injury

MR imaging of the rotator cuff: peritendinous and bone abnormalities in an asymptomatic population.

MR imaging of the shoulder was performed in an asymptomatic population to determine the prevalence of MR-evident peritendinous and bone abnormalities. Findings were correlated with subject age and rotator cuff abnormalities. Dual-echo T2-weighted oblique coronal MR images of the shoulder were evaluated for 100 asymptomatic volunteers who were 19-88 years old. Twenty symptomatic patients with arthroscopic correlation were included as controls. Images were assessed independently by two reviewers with no knowledge of subject history or symptomatology. Bursal, peribursal, and bone findings were correlated with subject age and the appearance of the rotator cuff tendon. Changes characteristic of acromioclavicular joint osteoarthrosis were present in three fourths of the shoulders. One third had subacromial spurs. Changes in the peribursal fat plane and the presence of fluid in the subacromial-subdeltoid bursa paralleled the degree of MR-evident rotator cuff abnormalities. Joint fluid was observed in nearly all subjects. Our findings reveal a high prevalence of MR-evident bone and peritendinous shoulder abnormalities among asymptomatic individuals. The prevalence of subacromial spurs and humeral head cysts correlated closely with the severity of MR-evident rotator cuff abnormalities, as did changes in the bursa and peribursal fat. Acromioclavicular joint osteoarthrosis is seen in many shoulders independently of rotator cuff disease; therefore, its presence alone does not appear to be a reliable indicator of pain or tendon disease.