MR imaging of rotator cuff injury: What the clinician needs to know
ABSTRACT The rotator cuff muscles generate torque forces to move the humerus while acting in concord to produce balanced compressive forces to stabilize the glenohumeral joint. Thus, rotator cuff tears are often associated with loss of shoulder strength and stability, which are crucial for optimal shoulder function. The dimensions and extent of rotator cuff tears, the condition of the involved tendon, tear morphologic features, involvement of the subscapularis and infraspinatus tendons or of contiguous structures (eg, rotator interval, long head of the biceps brachii tendon, specific cuff tendons), and evidence of muscle atrophy may all have implications for rotator cuff treatment and prognosis. Magnetic resonance imaging can demonstrate the extent and configuration of rotator cuff abnormalities, suggest mechanical imbalance within the cuff, and document abnormalities of the cuff muscles and adjacent structures. A thorough understanding of the anatomy and function of the rotator cuff and of the consequences of rotator cuff disorders is essential for optimal treatment planning and prognostic accuracy. Identifying the disorder, understanding the potential clinical consequences, and reporting all relevant findings at rotator cuff imaging are also essential.
- SourceAvailable from: Miroslav Heřman[Show abstract] [Hide abstract]
ABSTRACT: Background: This retrospective study reports the types, frequency, and relationships of lesions affecting a malfunctioning shoulder joint. Aims: Determination of the frequency and mutual relationships of lesions of the shoulder joint in cases of malfunction. Methods: In a set of 79 patients, which consisted of 55 men and 24 women sent for an MRI during a period of 14 months, we retrospectively evaluated the frequency and mutual relationships between lesions of the structures of the shoulder joint, specifically: lesions of the long head of the biceps tendon; superior labral tear from anterior to posterior (SLAP) lesions; glenohumeral traumatic changes; glenohumeral degenerative changes; acromioclavicular degenerative changes; acromioclavicular traumatic changes; pathological bursae, and lesions of the glenohumeral and acromioclavicular ligaments. We evaluated the frequency of representation of subacromial, subcoracoid, and posterosuperior impingements. Results: 30.4% of the patients had the simultaneous occurrence of two lesions of the shoulder joint, 25.3% lesions of three structures, and 19% lesions of one structure. The most common types of lesions were: bursae fillings in 17.2%; acromioclavicular degenerations in 15.7%; lesions of the long head of the biceps in 15.2%, and SLAP lesions in 12.6%. Conclusion: In the majority of cases, we found combined and simultaneous lesions of more than one structure of the shoulder joint. The most frequent pathological findings in our group were the presence of a filled bursa or bursae (34 patients, 17.2%), acromioclavicular degeneration (31 patients, 15.7%), and lesions of the long head of the biceps tendon (30 patients, 15.2%). The most common type of impingement was subacromial impingement with a lesion of m. supraspinatus (41 patients, 51.9%).
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ABSTRACT: Supraspinatus muscle disorders are frequent and debilitating, resulting in pain and a limited range of shoulder motion. The gold standard for diagnosis involves an invasive surgical procedure. As part of a proposed clinical workflow for noninvasive computer-aided diagnosis (CAD) of the condition of the supraspinatus, we present a method to classify three-dimensional shapes of the muscle into relevant pathology groups, based on magnetic resonance (MR) images. We obtained MR images of the shoulder from 72 patients, separated into five pathology groups. The imaging protocol ensures that the supraspinatus is consistently oriented relative to the MR imaging plane for each scan. Next, we compute the Fourier coefficients of two-dimensional contours lying on parallel imaging planes and integrate the corresponding frequency components across all contours. To classify the shapes, we learn the Fourier coefficients that best distinguish the different classes. We show that our method leads to significant improvement when compared to previous work. We are able to distinguish between normal shapes and shapes that possess a pathology with an accuracy of almost 100%. Moreover, we can differentiate between the different pathology groups with an average accuracy of 86%. We confirm that analyzing the three-dimensional shape of the muscle has potential as a form of diagnosis reinforcement to assess the condition of the supraspinatus. Moreover, our proposed descriptor based on Fourier coefficients is able to distinguish the different pathology groups with accuracies higher than those obtained by previous work, indicating its potential application to support a system for CAD of the supraspinatus.Academic radiology 08/2010; 17(8):1040-9. DOI:10.1016/j.acra.2010.04.006 · 2.08 Impact Factor
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ABSTRACT: The antioxidant activity of astaxanthin against paraquat (PQ) induced oxidative stress in primary cultures of chicken embryo fibroblasts (CEF) was assessed. Activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were measured as indices of oxidative stress. CEF incubated with 0.25 mM PQ for 18 h exhibited increased SOD and CAT activities and decreased GSH-Px activity compared to control. Incorporation of astaxanthin (0.1–10 nM) into 0.25 mM PQ treated CEF reduced SOD and CAT activities. Astaxanthin (0.1–10 nM) returned GSH-Px activity to its control value. CEF grown in astaxanthin enriched media (0.1–10 nM) were also oxidatively stressed by exposure to 0.25 mM PQ. In these studies, astaxanthin enrichment (0.1–10 nM) of the medium returned all antioxidant enzyme activities to those seen in control cells.Nutrition Research 11/1995; 15(11-15):1695-1704. DOI:10.1016/0271-5317(95)02040-9 · 2.59 Impact Factor