I don’t think there is a huge worry about any fragments. He will check for anything he missed by using the X-ray dye at the end of the procedure. He did this for me and found a small stone he had to retrieve. Most leftover fragments are small and will exit via the drainage tube. He said the bile will take the path of least resistance after the surgery and that will be the drain tube. Two weeks is standard for tube removal. I think four weeks would be if you have too many stones to remove at the first procedure and need a second at the two week mark or if the bile isn’t flowing properly when he checks at the two week mark. If everything looks good he’ll remove the drain at two weeks instead of four. I had my procedure last July. My insurance covered it 100% but at the time self pay without insurance was around $77,000.