Question 10

The deep lymphatics of the anterior abdominal wall accompany the deeper arteries. In the lower abdominal wall, lymphatics following the inferior epigastric and deep circumflex vessels drain to the external iliac lymph nodes. This differs from superficial infraumbilical lymphatic drainage, which follows superficial subcutaneous vessels towards the superficial inguinal nodes. In the upper anterior abdominal wall, deep lymphatic vessels may drain to parasternal nodes along the superior epigastric artery. Laterally, deeper lymphatic pathways can follow intercostal, subcostal or lumbar arteries towards posterior mediastinal or lateral aortic nodes. Therefore, the combination of a deep lymphatic plane, lower abdominal location and association with inferior epigastric/deep circumflex vessels identifies the external iliac nodes.

A) Superficial inguinal nodes principally receive superficial infraumbilical lymphatics rather than the deep pathway described.

C) Axillary drainage is associated with superficial supraumbilical lymphatics.

D) Parasternal nodes receive important upper abdominal-wall drainage rather than the described lower deep pathway.

E) Posterior mediastinal drainage is associated with deeper lateral intercostal or subcostal pathways.

Part 1 MRCOG Revision Notes and Sample SBAs. Cambridge University Press, 2020. Section 1: Anatomy, Chapter 1. https://doi.org/10.1017/9781108644396