A 48-year-old patient is found to have a serum calcium of 10.9 mg/dL and PTH of 98 pg/mL (normal 15–65). A 99mTc-sestamibi scan shows a single focus of increased uptake at the lower pole of the right thyroid lobe. Intraoperative PTH monitoring is performed. If PTH drops by more than 50% from the pre-excision value to below the upper limit of normal within 10 minutes of gland removal, what does this indicate?

• A The gland excised was not the culprit adenoma
• B Further exploration for multiglandular disease is mandatory
• C The patient has MEN1 and needs four-gland exploration
• D Cure has been achieved (Miami criterion) ✓

Explanation

The Miami criterion for intraoperative PTH monitoring requires a > 50% drop from the highest pre-excision PTH value AND a fall into the normal range within 10 minutes of parathyroid adenoma removal. Satisfying both criteria indicates biochemical cure and allows termination of exploration without four-gland assessment. Failure to meet either criterion prompts further exploration for multiglandular disease.

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.