Benign teratomas of the mediastinum are rare tumors that represent 5 to 10% of mediastinal tumors. They remain asymptomatic for a long time and their discovery often reveals their bulky size. They occur most often in young subjects. We report the observation of a 6-year-old patient with a large mediastinal teratoma revealed by rest dyspnea and chest pain in a context of asthenia who was referred to our pediatric imaging department for a thoracic CT scan. Although benign mediastinal teratomas are slow growing, they can rarely become complicated and cause symptoms. Imaging is essential to make the diagnosis and to look for possible complications. The gold standard treatment is complete surgical resection.

Carotid-cavernous fistulas (CCF) are defined as abnormal vascular communication between the internal and external carotid arteries or their meningeal branches and the cavernous cavity. The objective of our work is to show the radiological signs allowing the diagnosis of a carotid-cavernous fistula. We report the case of a 40-year-old patient with a left carotid-cavernous fistula following a head trauma, who consulted the emergency room 3 days after his trauma because of persistent pulsatile headaches and the appearance of a left exophthalmos. A CT scan, a Doppler ultrasound followed by a cerebral MRI after injection of contrast medium were performed. An angio-MRI confirmed the diagnosis and showed the presence of a left carotid-cavernous fistula. The mode of revelation of post-traumatic CFC is often stereotyped and the association of intracranial murmur and pulsatile exophthalmos immediately evokes the diagnosis. Cross-sectional brain imaging allows the diagnosis to be made. Arteriography remains irreplaceable to confirm the existence of the breach and to analyze all the angiographic elements that will be important at the time of the final therapeutic decision. The diagnosis of carotid-cavernous fistula suspected clinically is confirmed on imaging in the presence of evocative signs.