ABSITE Colorectal questions and answers with solutions 2025

What does the SMA supply and what are its branches? -
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ANSWER Ascending and 2/3 of transverse colon
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Ileocolic, right and middle colic arteries
O O O O O




What does the IMA supply and what are its branches? -
O O O O O O O O O O



ANSWER 1/3 of transverse colon, descending colon, sigmoid and upper portion of the rectum
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Left colic, sigmoid artery, superior rectal artery
O O O O O O




What is the collateral circulation of the colon? - ANSWER Marginal artery of Drummond -
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runs alog colon margin connecting SMA to IMA
O O O O O O O O




Arc of Riolan - short direct connection between SMA and IMA
O O O O O O O O O O




What is the venous drainage of the colon? - ANSWER IMV --> splenic vein
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splenic vein + SMV = portal vein
O O O O O O




What is the arterial supply to the rectum? - ANSWER superior rectal artery (branch of IMA)
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middle rectal artery (branch of internal iliac)
O O O O O O




inferior rectal artery (branch of internal pudendal which is a branch of internal iliac)
O O O O O O O O O O O O O




What is the venous drainage of the rectum? - ANSWER Superior and middle rectal veins --> IMV
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Inferior rectal vein --> internal iliac veins --> IVC
O O O O O O O O




What is the lymphatic drainage of the rectum? - ANSWER superior and middle --
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> IMA nodal lymphatics
O O O




inferior --> primarily IMA nodes and internal iliac nodes
O O O O O O O O