Kalman M A
AJR Am J Roentgenol. 1978 Mar;130(3):493-8. doi: 10.2214/ajr.130.3.493.
In patients with adequate amounts of intramuscular fat, the normal contours of the muscles of the pelvic floor and side-walls may be visualized on plain radiographs. Knowledge of the relationships of these muscles to surrounding structures has been facilitated by computed tomography. Obliteration of the medial margin of the psoas muscle with an attendant soft tissue mass implies pathology in the region of the medial chain of external iliac lymph nodes; similarly, obliteration of the obturator internus shadow suggests internal iliac adenopathy. Nonnodal masses in these regions can cause similar radiographic abnormalities. The normal shadow of the piriformis muscle may simulate external iliac adenopathy. Pitfalls which may lead to overinterpretation are discussed.
在具有足够量肌内脂肪的患者中，骨盆底和侧壁肌肉的正常轮廓可在普通X线片上显示出来。计算机断层扫描有助于了解这些肌肉与周围结构的关系。腰大肌内侧缘消失并伴有软组织肿块提示髂外淋巴结内侧链区域存在病变；同样，闭孔内肌阴影消失提示髂内淋巴结肿大。这些区域的非结节性肿块可引起类似的影像学异常。梨状肌的正常阴影可能会模拟髂外淋巴结肿大。文中讨论了可能导致过度解读的陷阱。
