Intercostal veins drain into:

Ans. C Azygous veinRefi BDC 6th ed. vol. 1/221 -222; Keith L. Moore 5th ed. /105POSTERIOR INTERCOSTAL VEINS* One in each of the 11 spaces* On the right:# 1st drains into Rt. innominate vein (A)# 2nd, 3rd & sometimes the 4th unite to form Rt. Superior Intercostal vein (B) which drains into azygos vein.# From 5th to 11th & subcostal veins drain into azygos vein (C).* On the left:# 1st drains into Lt. innominate vein (A)# 2nd, 3rd & sometimes the 4th join to form Lt. Superior intercostal vein which drains into Lt innominate vein vein (B)# 5th, 6th, 7th & 8th form superior hemiazygos vein to azygos vein (D)# 9th, 10th, 11th & subcostal form inferior hemiazygos veins drain to azygos vein (E).