Intraoperative PTH monitoring (Miami criterion) is used to confirm successful parathyroid adenoma excision. The Miami criterion states the operation is successful when intact PTH falls by:
- A >30% from the highest pre-excision value at 10 minutes post-excision
- B >50% from baseline value and PTH enters the normal range
- C >50% from the highest pre-excision value within 10 minutes post-excision to within normal range ✓
- D To undetectable levels within 5 minutes
Correct answer: C. >50% from the highest pre-excision value within 10 minutes post-excision to within normal range
Explanation
The Miami criterion (Irvin et al.) requires a >50% fall from the highest pre-excision PTH value (either pre-incision or pre-excision, whichever is higher) at 10 minutes after excision AND that the absolute PTH value falls into the normal range. This two-part criterion predicts cure with approximately 97% accuracy. Simply achieving a >50% fall without entering the normal range may still indicate residual hyperfunctioning tissue.
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.