Muscular Sarcoidosis

ABSTRACT

There are four types of muscular sarcoidosis: nodular, chronic myopathy, acute myositis, and asymptomatic. The nodular type is important because it may be confused with a soft tissue tumor. Magnetic resonance (MR) imaging provides specific findings. A star-shaped central structure of decreased signal intensity, a ``dark star'' sign, is seen on the axial images. A long nodule with an inner stripe of decreased signal intensity and outer stripes of increased signal intensity, a ``three stripes'' sign, is seen on the coronal and sagittal images. In the chronic myopathy type, the role of MR imaging is limited. Gallium scintigraphy, which reflects activity of inflammation, may show increased uptake. In the acute myositis type, MR imaging shows increased signal intensity, and gallium scintigraphy shows increased uptake; however, these findings are nonspecific.

KEYWORD

Muscular sarcoidosis - magnetic resonance imaging - gallium scintigraphy

REFERENCES

• 1 Zisman D A, Biermann J S, Martinez F J, Devaney K O, Lynch III P J. Sarcoidosis presenting as a tumorlike muscular lesion. Case report and review of the literature.  Medicine . 1999;  78 112-122
• 2 Silverstein A, Siltzbach L E. Muscle involvement in sarcoidosis. Asymptomatic, myositis, and myopathy.  Arch Neurol . 1969;  21 235-241
• 3 Otake S. Sarcoidosis involving skeletal muscle: imaging findings and relative value of imaging procedures.  Am J Roentgenol . 1994;  162 369-375
• 4 Otake S, Banno T, Ohba S, Noda M, Yamamoto M. Muscular sarcoidosis: findings at MR imaging.  Radiology . 1990;  176 145-148
• 5 Vanhoenacker P, Brijs S, Geusens E. MR imaging of primary muscular sarcoidosis. Case report.  Fortschr Roetgenstr . 1994;  161 570-571
• 6 Matsuo M, Ehara S, Tamakawa Y. Muscular sarcoidosis.  Skeletal Radiol . 1995;  24 535-537
• 7 Garcia O M, Sarma D. Gallium scanning in a patient with sarcoidosis.  Clin Nucl Med . 1983;  8 557
• 8 Rohatgi P K, Singh R, Vieras F. Extrapulmonary localization of gallium in sarcoidosis.  Clin Nucl Med . 1987;  12 9-16
• 9 Otake S, Imagumbai N, Suzuki M, Ohba S. MR imaging of muscular sarcoidosis after steroid therapy.  Eur Radiol . 1998;  8 1651-1653
• 10 Edan G, Bourguet P, Delaval P, Herry J Y. Gallium-67 imaging in muscular sarcoidosis.  J Nucl Med . 1984;  25 776-778
• 11 Patel N, Krasnow A, Sebastian J L. Isolated muscular sarcoidosis causing fever of unknown origin: the value of gallium-67 imaging.  J Nucl Med . 1991;  32 319-321
• 12 Liem I H, Drent M, Antevska E, Lamers R JS, Heidendal G AK. Intense muscle uptake of gallium-67 in a patient with sarcoidosis.  J Nucl Med . 1998;  39 1605-1607