FM is the most common benign cause of SVC obstruction. Imaging findings include a hilar or mediastinal mass causing mediastinal widening. The right paratracheal region is the most common location for occurrence of a mass. Focal FM tends to have calcified masses whereas calcification is less common in diffuse FM.
Differential considerations include:
- bronchogenic carcinoma - usually older patient, doesn't calcify
Rossi SE, McAdams HP, Rosado-de-Christenson ML, et al. Fibrosing mediastinitis. Radiographics 2001;21:737-57.