Results:1 CT demonstrated clear boundary and homogenous density in symptomless, near oval and symmetry. Normal cross section areas of scalene anterior muscle is 1.3793 0.0948cm2, normal CT value is 54.594 2.0106;

• 结果：1无症状者前斜角肌横断面形态双侧对称，成近椭圆形，轮廓清晰，与周围组织界限清楚，两侧横断面面积及CT值相近，C_6上缘-C_7上缘水平正常前斜角肌横断面面积为：1.；3793±0