The surgery goes as planned. Wilson watches from the window above the operating theater. Outside in the hallway/waiting room, Mom waits anxiously, something she's got to be almost used to doing by now. Chase, down on the floor, looks up at Wilson and slowly shakes his head. I thought that meant that there was no tumor and that House subjected a dying girl to open heart surgery for nothing, but then Wilson goes out and tells Mom that they did indeed find a tumor in Andie's lung, extending to her heart. It was growing along the heart wall, which made it somehow impossible to see on the MRI. To remove the tumor, they have to take the heart out entirely, remove the tumor behind it, and replace damaged heart tissue with patches of cow's heart walls. If the tumor is too big, there won't be enough heart left for Andie to survive once they remove the tumor. And if the tumor's metastasized, Andie is double terminal.
Since we're only at minute twenty-seven of an hour-long show, Chase puts drops in unconscious Andie's eyes, whereupon he finds a bleed in the right one. Because the whole cow-heart-double-terminal-cancer thing wasn't bad enough.
House still has his hay fever the next day as he and Wilson exposit that they removed the tumor from Andie's lungs and heart, only to find a bleed in her eye that couldn't have been caused by a tumor, nor could the hallucinations, since the tumor was benign. House says that they must be looking at a third coincidence now, and they head into the meeting room, where the Cottages, like Wilson, find it hard to believe that they're now looking for a third problem in poor Andie's body. Chase says that a clot could have caused the retinal bleed, and Foreman adds that a clot might also cause a mini-seizure, which sometimes leads to post-seizure psychosis, when the brain tries to correct itself by hallucinating. Wait -- when did Andie have the seizure? Was that why her version of "Beautiful" was so bad? Wilson admits that the clot can explain the eye and the hallucination, but he still doesn't understand how a tumor "the size of an octopus" wrapped around a girl's heart fits into all this. I don't understand how a tumor the size of an octopus wasn't seen on any of the tests they did. Unless it was one of those tiny octopi you get in calamari. Wilson just can't believe that Andie has three things wrong with her that are all unrelated. Humans can't be "lemons," he says. House says something nonsensical about the tumor being Afghanistan and the clot being Buffalo. He clarifies that the tumor is like Al-Qaeda and the clot is one of its splinter cells in Buffalo, still existing even after the main base has been wiped out. So that's what happened to Mary after her parents shipped her off to Buffalo! What House is actually saying, as it relates to Andie, is that the tumor threw the clot before it was removed, and that's what caused the retinal bleed and the hallucination that put Andie in their care in the first place. He orders them to do an angiogram of Andie's brain to find the clot.