Case report:

These are 2 different cases - one with interrupted vena cava and azygos continuation and the other is a case where the course of the azygos was easily seen, but everything was normal.

Case 1: 37 years 2-para scanned at 23 weeks; azygos vein with normal inferior vena cava. 

Images show visible azygos vein in its normal site, behind the heart near the aorta and draining in the superior vena cava. The images also show normal inferior vena cava, and the size of the azygos vein is much smaller than the aorta. A repeat scan at 27 weeks confirmed the findings. Postnatal development was normal.

Case 2: 29 year-old nullipara scanned at 23 weeks, azygos vein with interrupted inferior vena cava. Images and video show absence of inferior vena cava with azygos continuation, course of azygos vein behind the heart and its drainage into the superior vena cava. The azygos vein was enlarged when compared to the size of the aorta. The findings were confirmed at 32 weeks and after birth.

Figure 1-5: At 23 weeks; azygos vein with interuption of inferior vena cava.