Multiple fluid levels are present. Lymphangiomas are rare, benign tumors which most commonly affect the posterior triangle in the neck. In the mediastinum, lymphangiomas are located more commonly in the anterior mediastinum than in either the middle or posterior mediastinum. They frequently display an infiltrative growth pattern, insinuating around vessels with little displacement. They usually demonstrate water attenuation, sometimes with fat or soft tissue septations.
Calcification is rare.
As in this case, they appear as soft lesions. MRI is useful for demonstrating the proteinaceous content of lymphangiomas, which is seen as high T1 signal that does not saturate with fat saturation techniques.