So let's talk a little bit about pituitary adenomas and surgical approaches and specifically now we'll shift gears a little bit and talk a little bit about transcranial approaches to pituitary masses. The first question is, you know, why would you come from above when you've got a nice corridor, the transsphenoidal approach that lets you get to the pituitary from below and usually gets you there faster. Patient recovers faster. Surgeon typically likes that operation better. Patient typically likes that operation better. But there are times when you have to access the pituitary gland and any tumor associated with it from above or a transcranial approach. And the reasons for that are sometimes you'll come from below or transsphenoidal approach, and the tumor, and this is uncommon by the way, but the tumor is simply so firm that it doesn't deliver itself down to the surgeon and, sometimes that would obligate a transcranial approach. Admittedly, that's quite uncommon.