目的　探讨脂质代谢性肌肉病的超声变化规律及其产生的机制。方法对５例经肌肉活检证实的脂质代谢性肌病患者用７．５ ＭＨｚ超声探头进行四肢肌肉纵断面和横断面检查，５例正常人作对照。对肌肉活检的油红“０”染色切片进行计算机形态计量分析，观察脂肪滴所占肌纤维横切面的面积比。结果病理检查发现脂肪在不同肌纤维的沉积具有明显肌纤维类型的选择性，间质无增生。形态计量分析显示脂肪滴在肌纤维内的沉积呈现梯度分布。肌肉超声显示肌肉纹理不清，在股四头肌最明显，无明显肌萎缩。结论脂质代谢性肌肉病存在明显的肌肉超声改变，肌肉超声改变主要和脂肪滴在肌纤维内沉积有关，和结缔组织增生无关，肌纤维本身病变也可以导致肌肉超声异常。 Objective To investigate the ultrastructural changes of lipid metabolism muscle disease and its mechanism. Methods Five patients with lipid metabolism myopathy confirmed by muscle biopsy were examined by longitudinal and transverse cross-sectional examination of the muscles of the limbs with a 7.5 MHz ultrasonic probe. Five normal controls were used as controls. Muscle biopsy oil red “0” stained sections were computerized morphometric analysis of fat droplets accounted for the cross-section of the muscle fiber area ratio. Results Pathological examination revealed that the deposition of fat in different muscle fibers showed obvious muscle fiber type selectivity without interstitial hyperplasia. Morphometric analysis showed that the fat droplets showed a gradient distribution in the muscle fiber. Muscle ultrasound showed muscle texture is unclear, the most obvious in the quadriceps, no significant muscle atrophy. CONCLUSIONS: There is a significant change of muscle metabolism in lipid metabolism muscle disease. The changes of muscle ultrasound are mainly related to the deposition of fat droplets in muscle fibers, but not to the proliferation of connective tissue. The muscle fibers themselves may also lead to abnormal muscle ultrasound.