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
