This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Head and neck, Subject name: Surgery
Premature filling of veins is a manifestation in cerebral angiography of: 
Select and explain. 
A. Trauma, B. Brain tumor, C. Aeriovenous malformation, D. Aerial occlusion
C: Aeriovenous malformation
Answer: C: Aeriovenous malformation 
Explanation: Diagnosis of AVM is made by conventional catheter cerebral angiography Diagnosis is based on demonstration of aeries and veins on the same conventional angiographic image, proving the high-flow shunting of blood (leading to early filling of veins) through the nidus network or fistulous vessels In the typical AVM, there is a cloudlike nidus, or network of smaller vessels, well seen on angiography Ref: Sabiston 20th edition Pgno: 1925