NBME 20 Answers : Block 1 : #12 = A 72-year-old woman with dysphagia is undergoing ...

NBME 20 Answers

nbme20/Block 1/Question#12

A 72-year-old woman with dysphagia is undergoing ...

Right kidney

+9 upvote downvote
submitted by onyx(21),

Thoracic duct relations.

consuela_salon This was the picture that I liked the most for this question. If you imagine that the injury is at the level of the left subclavian vein (LSV) and thoracic duct (TD) crossing each other, maybe it will help you realize that the left breast & left upper extremity bypass the injury. The right lung is drained by the right lymphatic duct, not the TD (see one of the links bellow). And the heart is where eventually all the drainage is going to end up to be pumped again (TD -> LSV -> SVC -> heart). +4

mbourne To keep it simple, the Thoracic Duct drains lymph from the entire body EXCEPT for 3 structures: Right Upper Extremity Right Thoracic Cavity Right Side of Head and Neck These 3 areas are drained by the Right Lymphatic Duct which enters the Right Internal Jugular Vein +

+3 upvote downvote
submitted by onyx(21),

The mass described is in the posterior mediastinum (see images below). The thoracic duct is damaged “near the mass”, hence drainage of organs distal to that point will be affected. The images below should clarify.

+3 upvote downvote
submitted by hayayah(536),

The left upper extremity and breast are drained by the axillary lymph node. The kidney is drained by the thoracic duct. The heart has its own lymph system going on surrounding the heart.

+3 upvote downvote
submitted by thomas(4),

headshot

https://slideplayer.com/slide/10842513/39/images/24/Drainage+territory+Drains+lymphatics+from+whole+of+the+body+except.jpg

jointaccount Left breast & L UE drained by axillary. With the remaining choices, R kidney is the only choice outside the territory of the right lymphatic duct +

+0 upvote downvote
submitted by divya(12),

for anatomy dummies like myself

+0 upvote downvote
submitted by consuela_salon(6),

This was the picture that I liked the most for this question. If you imagine that the injury is at the level of the left subclavian vein (LSV) and thoracic duct (TD) crossing each other, maybe it will help you realize that the left breast & left upper extremity bypass the injury. The right lung is drained by the right lymphatic duct, not the TD (see one of the links bellow). And the heart is where eventually all the drainage is going to end up to be pumped again (TD -> LSV -> SVC -> heart).

consuela_salon (I meant the picture posted by onyx) +

+0 upvote downvote
submitted by onyx(21),

Mediastinal relations.

+0 upvote downvote
submitted by onyx(21),

Thoracic duct relations.