Go on Youtube. There is a mountain of information on the parathyroid glands (4 glands 2 B exact). What I've learned is that if there is a tumor, it may or may not show up on a scan. There was one surgery where only 1 turmor showed on the scan, the 2nd tumor was hiding. It's a 15 minute day surgery with about a 1" incision. I wish this site would allow links bt it doesn't. Go to youtube.com ... ALWAYS BE PREPARED B4 MEETING W/UR DR. WITH ALL SURGERY THERE R RISKS. The vocal chords are very close to the parathyrid glands. This is the video U will want 2 C ... Parathyroid Operation: State of the art Surgery in 13 minutes by NORMAN PARATHYROID CENTER ... Some of the symptoms I've had for years bt those symptoms mimic other possibilities as well. Best blessings on your journey ...