Lungs
2. Findings and Diagnosis
The azygo-esophageal junction line (pink arrowheads b) is mildly obliqued to the right and terminates at the downstream portion of the azygous vein just before it enters into the SVC (blue arrowhead, b)
Ashley Davidoff MD TheCommonVein.net 33435cL
Azygoesophageal Junction (AEJ) Line
- The azygoesophageal junction (AEJ) line is a thin vertical interface seen on frontal chest X-ray (CXR), formed by the right lung adjacent to the interface of the azygos vein, esophagus, and adjacent mediastinal fat.
- It extends from the azygos arch (T4-T5) downward to the diaphragm on the right side of the mediastinum.
Relevance and CXR Importance
- Normal AEJ Line: Appears as a thin, straight, or slightly curved vertical line on the right paramediastinal region.
- Widening, bowing, or distortion of the AEJ line can indicate:
- Mediastinal pathology (e.g., lymphadenopathy, esophageal masses, hiatus hernia).
- Azygos vein enlargement (e.g., right heart failure, SVC obstruction).
- Esophageal abnormalities (e.g., dilated esophagus in achalasia, esophageal cancer).
- Subcarinal or paratracheal lymphadenopathy (e.g., TB, lymphoma, metastases).