Circumscribing or periadenomal vessel: a helpful angiographic finding in certain islet cell and parathyroid adenomas

Angiographic visualization of a vein or artery partly or completely encircling small adenomas of islet cell or parathyroid origin is an occasional helpful localizing sign, particularly when the overlying pancreas or thyroid glands are intensely stained. Three examples (two islet cell; one parathyroid) are presented.