The most likely cause of a popliteal mass is a Baker's cyst, but one must consider soft tissue tumors also.

腘窝肿块是最常见的腘窝滑膜囊肿，但是腘窝神经鞘瘤也是需要考虑的一种疾病。

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CT revealed a soft tissue mass or nodule (12 cases), cyst lesion (9 cases), with emphysema around the pulmonary sequestration.

CT示软组织密度肿块或结节12例，囊肿样病变9例，病灶周围肺气肿。

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The expected course of ovarian cysts varies with a woman's age, the size of the cyst, whether there is a family history of ovarian cysts, and whether the cyst is fluid-filled, appears to be a solid mass of tissue, or has both fluid and solid components.

CNN: What are the potential problems with ovarian cysts?