Fig. 21
From: Persistent left superior vena cava: clinical importance and differential diagnoses
Left superior intercostal vein. a–c Axial CT images depict a thin-caliber LSIV (red arrows) in a healthy patient. d–f After developing SVC occlusion (green arrow, f), axial CT images show multiple mediastinal venous collaterals and markedly enlarged LSIV (red arrows) in the same patient