Autofluorescence in Parathyroidectomy: Signal Intensity Correlates with Serum Calcium and Parathyroid Hormone but Routine Clinical Use is Not Justified

• Published in: World journal of surgery 2019-06, Vol.43 (6), p.1532-1537
• Main Authors: DiMarco, Aimee, Chotalia, Ravi, Bloxham, Ruth, McIntyre, Charlotte, Tolley, Neil, Palazzo, F. Fausto
• Format: Article
• Language: English
• Subjects: Abdominal Surgery; Adult; Aged; Aged, 80 and over; Calcium; Calcium - blood; Cardiac Surgery; Composition; Correlation analysis; Female; Fluorescence; General Surgery; Humans; Hyperparathyroidism; Infrared radiation; Intraoperative Care; Male; Medicine; Medicine & Public Health; Middle Aged; Original Scientific Report; Parathyroid; Parathyroid Glands - diagnostic imaging; Parathyroid hormone; Parathyroid Hormone - blood; Parathyroidectomy; Patients; Prospective Studies; Reproducibility of Results; Spectroscopy, Near-Infrared; Surgery; Thoracic Surgery; Vascular Surgery; Vitamin D; Weight; Young Adult
• ISSN: 0364-2313; 1432-2323
• DOI: 10.1007/s00268-019-04929-9

Background The inability to identify the pathological gland at surgery results in failure to cure hyperparathyroidism in 2–5%. The poorly understood characteristic of parathyroid tissue to manifest autofluorescence (AF) under near-infrared (NIR) light has been promoted as an intraoperative adjunct in parathyroid surgery. This study sought to explore potential clinical correlates for AF and assess the clinical utility of AF in parathyroid surgery. Methods Consecutive patients undergoing parathyroid surgery for primary and renal disease were included. NIR imaging was used intraoperatively and the degree of AF of parathyroid glands graded by the operating surgeon. Variables assessed for correlation with AF were: pre-operative serum calcium and PTH, SestaMIBI positivity, gland weight and histological composition. Results Ninety-six patients underwent parathyroidectomy over an 8-month period: 49 bilateral explorations, 41 unilateral and 6 focussed lateral approaches: 284 potentially ‘visualisable’ glands in total. Two hundred and fifty-seven glands (90.5%) were visualised with NIR. Correlation was found between the degree of fluorescence and pre-operative serum calcium and PTH, but not between gland weight and SestaMIBI positivity. In those with renal hyperparathyroidism, a predominance of oxyphil cells correlated with increased AF. Conclusion Autofluorescence intensity correlates with serum calcium, PTH and gland composition. Further refinements would be required for this information to be of value in a clinical setting. Improvements allowing NIR to visualise the additional 9.5% of parathyroids and overcome the variation in signal intensity due to depth of access are required for the routine adoption of this technology. At present, its routine use in a clinical setting cannot be justified.