Intraoperative imaging systems using near-infrared autofluorescence (NIRAF) may help identify and preserve parathyroid glands during total thyroidectomy and may decrease the risk for postoperative hypocalcemia, according to study results presented at the 89th Annual Meeting of the American Thyroid Association, held October 30 to November 3, 2019 in Chicago, Illinois.
As inadvertent removal or damage of the parathyroid glands during total thyroidectomy may cause postoperative hypocalcemia, every effort is made to preserve the glands. The goal of the current study was to assess whether intraoperative imaging systems using NIRAF light can improve the identification and preservation of the parathyroid glands and reduce the risk for postoperative hypocalcemia.
The randomized controlled trial included patients who underwent total thyroidectomy treated in 3 hospitals in France between September 2016 and October 2018. The patients were randomly assigned to conventional total thyroidectomy or NIRAF-assisted total thyroidectomy.
Postoperative hypocalcemia, defined as a calcium level <8 mg/dL at postoperative day 1 or 2, was the primary outcome and was classified as temporary (≤6 months) or permanent (>6 months). Main secondary outcomes included the rates of parathyroid gland autotransplantation and inadvertent resection.
The study cohort included 241 participants (mean age, 53.6 years [SD 13.6 years]; 79.3% women), including 121 patients who underwent NIRAF-assisted thyroidectomy (intervention group) and 120 who underwent conventional thyroidectomy (control group).
While there was a significant difference between the intervention and control groups in risk for temporary postoperative hypocalcemia (9% vs 22%, respectively; P =.0068), there was no significant difference in the risk for permanent hypocalcemia (0% vs 1.6%, respectively). After adjustment for possible confounders, risk for hypocalcemia was 65% lower with the use of NIRAF compared with conventional methods (adjusted odds ratio, 0.35; 95% CI, 0.15-0.83; P =.02).
Furthermore, rates of parathyroid autotransplantation (3.3% vs 13.3%, respectively; P =.009) and the number of inadvertently resected parathyroid glands (2.5% vs 11.7%, respectively; P =.006) were significantly lower with the use of NIRAF compared with the control group.
“The use of NIRAF for the identification of the [parathyroid glands] helped improve significantly temporary postoperative hypocalcemia rate and parathyroid preservation after total thyroidectomy,” concluded the researchers.
Benmiloud F, Godiris-Petit G, Gras R, et al. Use of autofluorescence-based detection of the parathyroid glands during total thyroidectomy and risk of postoperative hypocalcemia: Results of the multicenter randomized controlled PARAFLUO trial. Presented at: American Thyroid Association 2019 Annual Meeting; October 30-November 3, 2019; Chicago, IL. Oral 26.