The wall has thickened on my gallblader, and no sign of stones. can this be treated without surgery?

Depends: Thickened gallbladder wall is often associated with edema, ischemia and infection in the gallbladder. If you are truly symptom free, then a follow up ultrasound to monitor the thickness is indicated. Removing the diseased gallbladder is the best therapy. A diseased gallbladder carries risk for life threatening complications. The surgery to remove gallbladder is low risk.

Discuss with DR: Generally, gallbladder disease is definitively treated with surgical removal of gallbladder. You should discuss with your family physician and/or your surgeon if you have a surgeon.