Department of Orthopaedic Surgery, Nara Medical University, Nara, Japan.
Department Orthopaedic Oncology, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy.
Curr Med Imaging. 2021;17(2):157-165. doi: 10.2174/1573405616666200806173258.
Fluid-fluid levels result from the separation of two fluids of differing densities within a cavernous space with the boundary between the two layers running in a horizontal plane at 90 degrees to the direction of gravity. Magnetic resonance imaging is the most sensitive imaging modality to identify fluid-fluid levels. Although the most common bone lesions containing fluid-fluid levels are aneurysmal bone cyst and telangiectatic osteosarcoma, fluid-fluid levels can be observed in a wide variety of bone and soft tissue lesions. Therefore, fluid-fluid levels cannot be considered diagnostic of any particular type of tumor and the diagnosis should be made on the basis of other clinical, radiological and pathological findings. This article summarizes the pathophysiology and imaging characteristics of fluid-fluid levels and discusses the differential diagnosis of tumors with this imaging sign.
液-液平面是由于两种密度不同的液体在腔隙内分离而产生的，两层之间的边界以与重力方向成 90 度的水平平面延伸。磁共振成像是识别液-液平面最敏感的成像方式。虽然最常见的含有液-液平面的骨病变是动脉瘤样骨囊肿和毛细血管扩张性骨肉瘤，但液-液平面也可以在广泛的骨和软组织病变中观察到。因此，液-液平面不能被认为是任何特定类型肿瘤的诊断依据，诊断应基于其他临床、放射学和病理学发现。本文总结了液-液平面的病理生理学和影像学特征，并讨论了具有这种影像学表现的肿瘤的鉴别诊断。
