No contrast media extravasation of the aorta is found. Angiography also does not detect a leakage. Figures 2 and 3. One day later, unenhanced CT is performed. The mass is primary hyperintense, suggestive of bleeding.
Surgery confirms bleeding in the posterior mediastinum.
The tumor is excluded. Since there was no significant enhancement after contrast media application and the mass was hyperintense with 60 Hounsfield units on unenhanced CT, bleeding was the likeliest cause although no direct leakage could be found. The circumscribed form of the bleeding mass is uncommon. Normally, intrathoracic bleeding is spread more diffusely in the mediastinum. An explanation would be that the patient exhibited an abnormal tendency for venous bleeding at puncture sites, so that slow venous bleeding was suggested to be the underlying cause in this case.