MR and CT in the evaluation of sarcoid myopathy

Respiratory Failure due to Diaphragm Sarcoidosis Diagnosed by a Computed Tomography-guided Needle Biopsy

Sarcoidosis is a multisystem noncaseating granulomatous disorder of unknown etiology that can be found in almost any organ, but symptomatic respiratory muscle involvement is rare. We herein report the case of a 77-year-old woman with diaphragm sarcoidosis diagnosed by a computed tomography (CT)-guided needle biopsy that was successfully treated with a corticosteroid. The patient presented with dyspnea that lasted for two weeks and respiratory failure. CT revealed diffuse diaphragm thickening with contrast enhancement, which might be a characteristic imaging finding for diaphragm myopathy/myositis, including sarcoidosis. A CT-guided needle biopsy proved useful for the diagnosis of diaphragm sarcoidosis.

Applications of cardiac magnetic resonance in electrophysiology

Contemporary methods for evaluation and treatment of arrhythmia are increasingly dependent upon characterization of the underlying myocardial substrate. Cardiovascular magnetic resonance offers unsurpassed soft tissue resolution capable of visualizing detailed cardiac anatomic features and intra-myocardial barriers to conduction. Non-invasive visualization of such anatomic detail has the potential to improve methods to diagnose, risk stratify, and treat patients with arrhythmia. This review describes a brief overview of the current knowledge on the applications of cardiac magnetic resonance for evaluation and treatment of patients with arrhythmia.

Magnetic resonance imaging in the evaluation of non-ischemic cardiomyopathies: current applications and future perspectives

Patients with non-ischemic cardiomyopathy often represent a diagnostic challenge, and correct etiologic diagnosis may influence outcomes. Lately, delayed myocardial enhancement MR imaging has been developed and is currently being used for a growing number of clinical applications. On delayed enhancement MR images, scarring or fibrosis appears as an area of high signal intensity, and the pattern by which this enhancement occurs in the myocardium allows distinction of many different pathologies. In nonischemic cardiomyopathy, the delayed enhancement usually does not occur in a coronary artery distribution and is often midwall rather than subendocardial or transmural. It could also guide myocardial biopsy to an affected area, increasing its yield. Cardiac magnetic resonance imaging has now a definitive role in clinical practice, and its capability to non-invasively provide high resolution images of the heart with good tissue characterization is redefining the understanding of the conditions that can adversely affect the myocardium.

MRI to assess arrhythmia and cardiomyopathies

Cardiovascular magnetic resonance (CMR) is highly precise for morphological and functional analyses of the myocardium, and has been used to assess different types of cardiomyopathies. Its ability to characterize tissue, especially with gadolinium (Gd) delayed-enhancement techniques, has shown promising results for the diagnosis of arrhythmogenic cardiomyopathies. In this review we discuss the background and potential of this approach, as well as its usefulness for assessing arrhythmias and cardiomyopathies.

Delayed enhancement cardiovascular magnetic resonance assessment of non-ischaemic cardiomyopathies

Non-ischaemic cardiomyopathies (NICMs) are chronic, progressive myocardial diseases with distinct patterns of morphological, functional, and electrophysiological changes. In the setting of cardiomyopathy (CM), determining the exact aetiology is important because the aetiology is directly related to treatment and patient survival. Determining the exact aetiology, however, can be difficult using currently available imaging techniques, such as echocardiography, radionuclide imaging or X-ray coronary angiography, since overlap of features between CMs may be encountered. Cardiovascular magnetic resonance (CMR) imaging has recently emerged as a new non-invasive imaging modality capable of providing high-resolution images of the heart in any desired plane. Delayed contrast enhanced CMR (DE-CMR) can be used for non-invasive tissue characterization and may hold promise in differentiating ischaemic from NICMs, as the typical pattern of hyperenhancement can be classified as 'ischaemic-type' or 'non-ischaemic type' on the basis of pathophysiology of ischaemia. This article reviews the potential of DE-CMR to distinguish between ischaemic and NICM as well as to differentiate non-ischaemic aetiologies. Rather than simply describing various hyperenhancement patterns that may occur in different disease states, our goal will be (i) to provide an overall imaging approach for the diagnosis of CM and (ii) to demonstrate how this approach is based on the underlying relationships between contrast enhancement and myocardial pathophysiology.

Imaging Findings in Three Cases of the Nodular Type of Muscular Sarcoidosis

OBJECTIVE

Sarcoidosis is a granulomatous multisystem disorder that may uncommonly involve muscle. We report the sonographic and MRI findings in three cases of the nodular type of muscular sarcoidosis.

CONCLUSION

Intramuscular hypoechoic well-defined nodules in young patients or patients with a history of sarcoidosis suggest the diagnosis of intramuscular sarcoid. MRI is useful in detecting muscle sarcoid, evaluating the extent and distribution of muscle involvement, and monitoring the patient during follow-up after steroid therapy. MRI showed nodules that were iso- or hyperintense relative to muscle on T1-weighted sequences. On T2-weighted images and STIR sequences, we observed numerous intramuscular nodules of homogeneous high signal intensity. All nodules enhanced homogeneously on contrast-enhanced T1-weighted sequences. Disappearance of all nodules was seen on follow-up sonograms and MR images after patients had received steroid therapy.

MR imaging in nonneoplastic muscle disorders of the lower extremity

The exquisite tissue contrast and multiplanar capability of MRI make it the optimal imaging modality for diagnosing muscle injuries and other muscle disorders. These examinations can be performed with increasing speed because of improvements in gradient strength and software and coil design. Presently, some of the limitations of MRI of muscle relate to the lack of specificity of the findings. The advent of functional muscle MR[ will increase the understanding of human muscle diseases, and increasingly place MRI in a central role for diagnosis and follow-up analysis.

Muscular sarcoidosis: Ga-67 scintigraphy and magnetic resonance imaging

Ga-67 scintigraphy is helpful in the assessment of active extrapulmonary sarcoidosis. Muscular involvement of sarcoidosis is often asymptomatic or nonspecific, and laboratory examinations do not provide convincing evidence of muscular involvement. The authors report a case of muscular sarcoidosis detected by Ga-67 scintigraphy. In a patient who had fever and arthralgia of both knee joints, Ga-67 scintigraphy showed mediastinal and hilar involvement of sarcoidosis with unexpected extensive muscular uptake. Magnetic resonance imaging revealed in detail intramuscular infiltration of sarcoid granuloma. Ga-67 scintigraphy is useful in detecting inflammatory muscular involvement of sarcoidosis and other multiorgan involvement.

Sarcoidosis presenting as a tumorlike muscular lesion. Case report and review of the literature

Sarcoid myopathy presenting as a tumorlike lesion is an exceedingly rare presentation of sarcoidosis. Concurrent extramuscular involvement is common. Chest radiographs, if abnormal, may suggest the diagnosis. Magnetic resonance imaging is the preferred study for diagnosis and follow-up of tumorous sarcoid myopathy. Optimal therapy is not clear. Favorable responses have been cited with surgery or corticosteroids (alone or in combination). Azathioprine or alternative immunosuppressive agents (for example, antimalarials or methotrexate) may have a role in corticosteroid-recalcitrant patients. The role of local radiotherapy is controversial and should be reserved for severe localized disease refractory to aggressive medical therapy.

Magnetic resonance imaging of skeletal muscles in idiopathic inflammatory myopathies of adults

The purpose of the study was to describe typical MRI findings in various types of idiopathic inflammatory myopathies in adulthood and to correlate the MRI with histopathological and electromyographic findings, and the serum creatine kinase (CK) activity. A third goal was to assess the diagnostic value of the use of gadolinium-DTPA (Gd-DTPA). Fifty-eight patients (35 women, 23 men), aged 21-83 years (median age 59 years), suffering from idiopathic myositides (13 with acute and 45 chronic diseases; 25 with polymyositis, 14 with dermatomyositis, 8 with granulomatous and 11 with inclusion body myositides) were examined with MRI. Seventeen of them received an intravenous infusion of Gd-DTPA. Histopathological and MRI findings of 21 muscles of 18 patients were compared. MRI of skeletal muscles showed abnormal signal intensities in 56 (96.6%) of the 58 patients. MRI abnormalities were found more often than elevated CK activity (P < 0.001). The hyperintensity of T2-weighted images was more conspicuous than on T1-weighted images in 26 (44.8%) patients, indicating oedema-like abnormalities. MRI of 50 (86.2%) patients showed fat replacement. In acute myositides, oedema-like abnormalities were more often visible and in muscle lipomatosis less often visible than in chronic diseases (P < 0.05 each). In dermatomyositis oedema-like abnormalities were more and lipomatosis less frequent than in the other types of myositis (P < 0.005) and correlated with the acuteness of the disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Muscular ultrasound in idiopathic inflammatory myopathies of adults

To evaluate the value of myosonography in inflammatory myopathies ultrasound of skeletal muscles was performed in 70 patients, aged 21-82 years, suffering from histologically proven polymyositis (n = 30), dermatomyositis (n = 18), granulomatous myositis (n = 9), inclusion body myositis (n = 13), and in 102 control persons. The sensitivity of muscle ultrasound in detecting histopathologically proven disease (82.9%) was not significantly different from electromyography (92.4%) or serum creatine kinase activity (68.7%). The positive predictive value of ultrasound was 95.1%, the negative predictive value 89.2%, and the accuracy 91.3%. The different types of inflammatory myopathies presented with typical, but not specific ultrasound features. Polymyositis showed atrophy and increased echointensity predominantly of lower extremity muscles, whereas in dermatomyositis clear muscle atrophy was rare and echointensities were highest in forearm muscles. Echointensities were lower in dermatomyositis compared to poly- and granulomatous myositis. Granulomatous myositis was characterized by the highest echointensities and a tendency towards muscle hypertrophy. Severe muscle atrophy was the most impressive feature in the majority of patients with inclusion body myositis. Comparison of ultrasound and histopathological findings indicates that muscle lipomatosis has a much greater impact on muscular echointensity than does muscle fibrosis. Ultrasound of myositis improved clinical assessment of patients by supplying differential diagnostic clues based on precise muscle size measurements and identification of mesenchymal abnormalities, particularly muscle lipomatosis.