IVC obstruction presents with

IVC obstruction presents with Thoraco epigastric dilation Blockade of IVC causes a communication between SVC & IVC by azygos vein due to which blood from IVC enters the SVC. A communication also sets up b/w superior and inferior epigastric vein in the rectus sheath which drains into Brachiocephalic vein Internal thoracic vein. Superficial Epigastric vein forms collaterals with Lateral Thoracic vein thoracoepigastric vein in case of either IVC or SVC obstruction Normally blood flow in the veins of anterior abdominal wall is in upward direction above the plane of the umbilicus and in downward direction below the plane of umblicus. But in case of IVC obstruction it is completely in upward direction ( both above and below the plane)