Dual-Channel Near-Infrared Autofluorescence Imaging and AI Analysis to Locate Parathyroid Glands (PTFinder)

Prospective, paired, observational study at three endocrine-surgery centers. For each specimen:

PTFinder scan - stopwatch runs until the first gland is seen; all suspected glands are marked.

White-light exam - second investigator, blinded to device results, inspects the same specimen.

All marked tissue plus a random "negative" sample go to frozen section or rapid PTH strip; discrepancies are settled by permanent histology.

Outcomes

Primary - time to first gland; detection rate per specimen.

Secondary - sensitivity, specificity, PPV, NPV; post-operative PTH and calcium at 1 h, 24 h, 7 d; incidence of hypocalcaemia.

Sample size: 60 specimens per site (total = 180) gives 80 % power to detect a rise in detection rate from 70 % to 90 % (α = 0.05, McNemar).

Analysis: Paired tests for efficiency, mixed-effects models for accuracy and lab values; multiple imputation for missing data.

Safety & Oversight: PTFinder emits low-intensity NIR light only on ex-vivo tissue; no patient exposure. Device is investigational, not under an FDA IDE. Ethics approval obtained from Fujian Medical University Union Hospital IRB (FJMU-IRB-2025-PTF); other sites use the same central IRB agreement. Data are stored in a secure eCRF.

Collected images will also be used to train and test a deep-learning model for fully automated parathyroid recognition; model performance metrics constitute secondary outcomes.

Inclusion criteria

• Age ≥18 years.
• Scheduled for elective total thyroidectomy, hemithyroidectomy, or parathyroidectomy with removal of thyroid/parathyroid tissue.
• Able and willing to provide written informed consent for participation and specimen imaging.

Exclusion criteria

• History of neck irradiation or prior neck surgery that may distort parathyroid anatomy.
• Pregnancy or breastfeeding.
• Confirmed or suspected parathyroid carcinoma, or thyroid carcinoma requiring en-bloc parathyroid resection.
• Inability to understand the study procedures or to comply with follow-up.