Bildgebung bei Myopathien

Abstract

Until recently, the diagnosis of myopathies was mainly based on clinical examination, laboratory investigations, neurophysiology, muscle biopsy, and genetic analysis. Imaging techniques now play a central role in the evaluation of disorders of the central nervous system and the vessels. Muscle imaging by sonography, CT and MRI can be particularly useful in the assessment of myopathies as well. Sonography shows an increased echogenicity of muscles in many myopathies. On CT, differences in the X-ray absorption of muscles can be detected. Because CT uses ionising radiation, its use will be restricted to special cases. MRI is able to demonstrate subtle changes in muscle by detecting and differentiating fat deposition and oedema. MRI can therefore significantly improve the differential diagnosis of several forms of myositis and muscular dystrophies. In difficult cases it can aid in the selection of the best site for a muscle biopsy. The development of new contrast agents or techniques like magnetic resonance spectroscopy opens up new perspectives for the diagnosis of myositis or metabolic myopathies.