Intraoperative PTH monitoring (Miami criterion) is used during parathyroidectomy for primary hyperparathyroidism. A patient has a pre-incision PTH of 180 pg/mL. After removal of a suspected adenoma, the 10-minute post-excision PTH is 48 pg/mL. This represents a fall of approximately 73% into the normal range. The Miami criterion is:

• A Not met, because the final PTH must be <20 pg/mL
• B Met, because PTH fell by >50% from pre-excision baseline into the normal range ✓
• C Not met, because a >50% fall alone is sufficient regardless of whether PTH is in normal range
• D Met only if both 5-minute and 10-minute post-excision values are <50 pg/mL

Explanation

The Miami criterion is met when intraoperative PTH falls by >50% from the highest pre-excision value (pre-incision or pre-manipulation) AND the resultant level falls within the normal range. In this case, 180 → 48 pg/mL is a 73% fall into the normal range (10–65 pg/mL), so the criterion is met, predicting successful cure with >97% accuracy and allowing termination of exploration. The PTH does not need to be <20 pg/mL.

Reference: Bailey & Love's Short Practice of Surgery, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.