The cavity was in the upper right lobe and doc felt that a Vat procedure could wedge out the cavity. He told me that as long as there was a cavity I would never resolve the MAC because there is no real blood supply to carry the drugs to the area. He was surprised that it collapsed and I attributed it to not nebulizing. I think Arikace is the only hope so far that may solve a cavity. Not certain. Talk with your doctor to gather all the pertinent info. Good luck.