
Dear Friends,
Due to the coronavirus scare, Dr Pepe and Miss Piggy have eloped to the Bahamas, leaving me alone in charge of the blog. Until his return in late March, I will present interesting cases in the Caceres’ Corner. I may even dare to present a Diploma case, although I am not as knowledgeable as Dr Pepe.
This week’s case is a preoperative PA radiograph of a 47-year-old woman.
Diagnosis:
1. Double aortic arch
2. Enlarged azygos vein
3. Mediastinal mass
4. None of the above
What do you see? Come back on Friday to see the answer!

Click here to see the answer
Findings: PA shows a right mediastinal bump at the confluence between the trachea and the RUL bronchus (A, arrow). There is a curved mediastinal line below (A, red arrow) and an extra mediastinal line in the left lower mediastinal border (A, yellow arrow).

The combination of these findings strongly suggests increased circulation in the azygos system, with prominent azygos and hemiazygos veins. In an asymptomatic patient the most likely diagnosis is a congenital interruption of the IVC with azygos continuation.
A double aortic arch can be ruled out because the right component raises higher than the left, and in this case the opposite occurs.

Unenhanced coronal CT confirms the dilated azygos arch (B, arrow) and the dilated ascending azygos (B-C, red arrows) and hemiazygos (C, yellow arrow)

Final diagnosis: Congenital interruption of the IVC with azygos continuation.
Congratulations to Hazem who was the first to give the correct answer and to Krister who gave a nice and accurate description of the findings.
Teaching point: this case is a good example of non-significant findings secondary to a congenital malformation, as mentioned in webinar eight.