Use Of MR Arthrography Research Articles

Lesions of the rotator cuff and biceps tendon

The rotator cuff is acomplex anatomical structure and the integrity is pivotal for the shoulder functionality. The pathologies are often multifactorial, resulting from degenerative, vascular, traumatic and mechanical factors. Radiography, ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI) form the pillars of radiological diagnostics. Each modality has specific advantages and limitations in the visualization and assessment of pathologies of the rotator cuff and biceps tendon. The MR arthrography offers additional insights in unclear cases by enhancing the differentiation between complete and partial tears. The MRI provides detailed information on tendon quality and associated damages, such as muscle atrophy and fat infiltration, making it the preferred method. The use of MR arthrography can identify defects through increased intra-articular pressure or contrast medium leakage. Muscle damage, as induced by edema in acute injuries or fatty degeneration in chronic conditions, can be evaluated using imaging techniques. Special attention is warranted for the infraspinatus, subscapularis and teres minor muscles due to their unique injury patterns and prevalences.

The use of MR arthrography to document an occult joint communication in a recurrent peroneal intraneural ganglion

The pathogenesis of intraneural ganglia remains controversial. Only half of the reported cases of the most common type, the peroneal nerve at the fibular neck, have been found to have pedicles connecting the cysts to neighboring joints detected with preoperative imaging or intraoperatively. We believe that all intraneural ganglia arise from joints, and that radiologists and surgeons need to look closely preoperatively and intraoperatively for connections. Not identifying these connections with imaging and surgical exploration has led not only to skepticism about an articular origin of the cyst, but also to a high recurrence rate after surgery. We present a patient who had two recurrences of a peroneal intraneural ganglion in whom a joint connection was not detected on previous MRIs and operations. Reinterpretation of the original films and high-resolution MRI demonstrated an "occult" joint connection to the superior tibiofibular joint. MR arthrography performed after exercise and 1 h delay, however, clearly showed the connection and communication. The joint connection was then confirmed at surgery through an articular branch. Postoperatively the patient regained nearly normal neurologic function, and follow-up MRI showed no cyst recurrence. MR arthrography with delayed imaging should be considered in cases of intraneural ganglia when a joint connection is not obvious on MRI.

Variants of the superior labrum and labro-bicipital complex: a comparative study of shoulder specimens using MR arthrography, multi-slice CT arthrography and anatomical dissection

The purpose of the present study was to evaluate the anatomical variability of the superior labrum and to compare the value of MR arthrography and multi-slice CT arthrography in the diagnosis of variants of the labro-bicipital complex. Forty-three human shoulder specimens (age range and mean age at death, 61-89 years and 78.3 years) were examined with the use of MR arthrography and multi-slice CT arthrography prior to joint exploration and macroscopic inspection of the superior labrum and labro-bicipital complex. Two radiologists evaluated MR and CT arthrograms, and the results were compared with macroscopic assessments. Anatomical dissection of all shoulder specimens revealed a sublabral recess in 32/43 (74%) cases. The attachment of the superior labrum was categorised as type 1 in ten (23%) cases, as type 2 in eight (19%), as type 3 in ten (23%), and as type 4 in 14 (33%) cases. One superior labrum showed detachment consistent with a superior labral anteroposterior (SLAP) type 3 lesion. On MR arthrography and CT arthrography the attachment of the superior labrum was categorised in concordance with macroscopic assessments in 79% and 84% of cases, respectively. The anteroposterior extension of sublabral recesses was accurately determined with MR and CT arthrography in 59% and 81% of cases, respectively. The attachment of the superior labrum shows considerable variability. Thus, exact depiction of variants is essential in order to avoid the false positive diagnosis of a superior labral tear (SLAP or Andrews lesion). Both, MR arthrography and multi-slice CT arthrography were effective in the detection and classification of sublabral recesses.

MR ARTHROGRAPHY OF THE HIP

This article discusses the use of MR arthrography for the evaluation of mechanical derangement of the hip. This technique is used primarily to evaluate the acetabular labral tears; however, the articular cartilage and joint capsule also are visualized. MR arthrography and hip arthrography have had a significant impact on the diagnosis and treatment of patients with mechanical hip pain.