Below the intracavernous internal carotid artery into the inferior cavernous sinus compartment The tumor extends to the lateral line inferiorly (under ICA) 1).
A significantly higher rate of remission can be achieved in grade 3A than in grade 3B and grade 4 adenomas. Therefore, the distinction into grades 3A, 3B, and 4 is of importance for the prediction of adenoma invasion and surgical treatment considerations 2)