In the aftermath of the Covid-19 scare, I have elected to show a new “Meet the Examiner” presentation, with questions and answers similar to a real examination. You will get the final answer at the end of the presentation.
Take your time before seeking the answer.
This case starts with PA and lateral chest radiographs of a 63-year-old man with acute chest pain. Would you suspect pulmonary embolism?
3.Need a CT
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Findings: the most significant finding is a broad right descending pulmonary artery (A, arrow) with an abrupt cut-off (A, red arrow), a sign of embolus in the artery (Palla sign). Oligemia of the right lung is also visible (Westermark sign). Both signs are suggestive of pulmonary embolism, to be confirmed with enhanced CT.
An enlarged azygos vein is also seen (A, yellow arrow), as well as a bump in the para-aortic line (A, blue arrow)
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Enhanced CT confirms multiple pulmonary emboli (C, arrows) as well as a large embolus in the right descending pulmonary artery responsible for the Palla sign (D, red arrow)
Caudal slices show a non-enhancing opacity in the lower mediastinum. What would be the most likely diagnosis?
4- Any of the above
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Findings: the serpiginous appearance of the opacity (E-F, red arrows) is compatible with all three diagnosis. Mediastinal varices are the most likely diagnosis because they are not unusual, and the top of the spleen appears to be enlarged (F, asterisk).
The varices are not opacified because the images were taken during the arterial phase.
Late images taken during the venous phase show enhancement of the varices (G, arrow). Coronal reconstruction confirms the splenomegaly and a whorl of varices (H, arrow) responsible for the bump of the para-aortic line in the PA radiograph. The varices (V) drain into an enlarged azygos vein (I, arrow). The increased flow explains the prominent azygos in the PA chest film.
Review of the clinical history discovered that the patient had cirrhosis of the liver.
Final diagnosis: mediastinal varices in a patient with liver cirrhosis and pulmonary embolism
Paraesophageal varices are not uncommon and are secondary to portal hypertension in patients with hepatic cirrhosis. When enlarged, they are visible as a lower middle mediastinal mass in about 8% of chest radiographs of cirrhotic patients.
They may be misdiagnosed in CT studies because they don´t enhance in the arterial phase, as happened in the case presented and in a second case shown below.
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58-year-old man with liver cirrhosis. PA radiograph shows widening of lower mediastinal lines, which are slightly undulated (A, arrows). There is increased opacity of the left upper quadrant of the abdomen and the lateral wall of the stomach is indented, suggesting splenomegaly. On the lateral view there is increased opacity of the middle lower mediastinum, with a suggestion of tubular structures (B, circle).
Enhanced axial CT (arterial phase) shows a non-enhancing mass in the middle mediastinum that looks like a cyst (C, arrows). Venous phase demonstrates multiple enhanced veins within the mass (D, arrows). The cirrhotic liver and the enlarged spleen are visible in the coronal CT (E) .
Dr. Pepe’s teaching points:
Remember that the mediastinum is composed mainly of vascular structures. When a mediastinal abnormality is present, always rule out a vascular origin (arterial or venous).