Aberrant left brachiocephalic vein: CT imaging findings and embryologic correlation

Area of Science:

• Vascular anatomy
• Congenital anomalies
• Embryology

Background:

• Aberrant left brachiocephalic vein (ALBCV) is an uncommon congenital vascular anomaly.
• Previous studies on ALBCV, particularly in the Chinese population, are limited.
• Understanding associated vascular variations and embryonic origins is crucial.

Purpose of the Study:

• To evaluate aberrant left brachiocephalic vein (ALBCV) using computed tomography (CT) in Chinese patients.
• To investigate associated vascular variations and potential embryonic correlations of ALBCV.
• To emphasize the diagnostic role of CT in identifying ALBCV.

Main Methods:

• Retrospective analysis of 14 cases of ALBCV diagnosed via CT scans of the chest since 1990.
• Review of imaging data focusing on azygos vein entry into the superior vena cava (SVC), SVC length, and coexisting cardiovascular abnormalities.
• Correlation with angiographic and magnetic resonance imaging (MRI) findings where available.

Main Results:

• ALBCV was primarily diagnosed incidentally via CT.
• In most ALBCV cases, the azygos vein entered the SVC at a level higher than or equal to the SVC origin.
• The average SVC length in ALBCV cases was shorter (approx. 5.6 cm) than the general population (approx. 7.0 cm).
• Three cases presented with associated vascular anomalies; right-sided aorta was implicated as an embryonic cause.

Conclusions:

• Computed tomography is a definitive modality for diagnosing aberrant left brachiocephalic vein (ALBCV).
• ALBCV is associated with specific patterns of azygos vein drainage and SVC length.
• Embryonic factors, such as right-sided aorta, likely contribute to the development of ALBCV.