Prevention of hypoparathyroidism: A step-by-step near-infrared autofluorescence parathyroid identification method

Radical Resection of Differentiated Thyroid Cancer in Elderly Patients: Evaluation of the Efficacy of the Immunocolloidal Gold Strip Method Combined with Nanocarbon Negative Imaging Tracing Technology for Parathyroid Gland Imaging

OBJECTIVE

Extant imaging methods used for the proper identification of the parathyroid glands to prevent post-operative hypothyroidism associated with the resection of differentiated thyroid cancer (DTC) are limited by factors such as low specificity, high cost, and technical complexity. This study, therefore, sought to investigate the efficacy of the immunocolloidal gold strip method combined with nanocarbon negative imaging tracing technology for parathyroid gland imaging during radical resection of DTC in elderly patients.

METHODS

A total of 100 elderly patients with DTC were enrolled and randomly divided into two groups: the control group and the observation group. The control group underwent conventional radical thyroidectomy with bilateral cervical lymph node dissection, while the observation group received the immunocolloidal gold strip method combined with nanocarbon negative imaging tracing technology for parathyroid gland imaging during the surgery. The baseline characteristics, intraoperative findings, postoperative parathyroid hormone (PTH), and serum calcium levels, as well as postoperative complications, were compared between the two groups.

RESULTS

There were no significant differences in age, gender, body mass index, comorbidities, or smoking history between the two groups. The observation group had a significantly higher number of parathyroid glands identified during surgery compared with the control group. The postoperative PTH and serum calcium levels at postoperative days 1 and 3 and at 6 months were significantly higher in the observation group than those in the control group. The incidence of postoperative hypoparathyroidism was significantly lower in the observation group.

CONCLUSION

The immunocolloidal gold strip method combined with nanocarbon negative imaging tracing technology is effective in identifying and preserving parathyroid glands during radical resection of DTC in elderly patients.

Parathyroid near-infrared autofluorescence differently benefits depending on the surgeon's skill for preventing from hypoparathyroidism after total thyroidectomy: A systematic review and meta-analysis

OBJECTIVE

To evaluate the role of parathyroid near-infrared autofluorescence in reducing the incidence of postoperative hypocalcemia and hypoparathyroidism after total thyroidectomy, and to determine which surgeons benefit most from parathyroid near-infrared autofluorescence use.

METHODS

A literature search was conducted in PubMed, Web of Science, and the Cochrane Library databases for English-language articles published from June 2011 to October 31, 2023. The inclusion criteria were studies conducted on patients who underwent total thyroidectomy for benign or malignant thyroid pathologies, comparing postoperative parathyroid function between parathyroid near-infrared autofluorescence techniques and conventional surgery with data on calcium and/or parathyroid hormone levels. The exclusion criteria included: reviews, letters, meta-analyses, case reports, animal experiments, or basic research. Of the initial 387 articles retrieved, we included 14. A meta-analysis was performed to calculate the pooled odds ratio and weighted mean deviation with a random-effects model. Main outcomes were Calcium and parathyroid hormone levels after total thyroidectomy with or without parathyroid near-infrared autofluorescence use.

RESULTS

Fourteen studies were included in the meta-analysis. Pooled odds ratios of temporary and permanent hypocalcemia were 0.56 (95% confidence interval 0.43-0.72) and 0.61 (95% confidence interval 0.33-1.13), respectively. Meta-regression analysis revealed that near-infrared autofluorescence benefits surgeons with the high incidence of temporary hypocalcemia by naked eye surgery (≥15%) by reducing temporary hypocalcemia (p = 0.0091) and skillful surgeons by increasing the number of autotransplanted parathyroid glands (p = 0.0225).

CONCLUSIONS

Parathyroid near-infrared autofluorescence has different benefits depending on the skill level of the surgeon.

Utilisation of Near Infrared Autofluorescence in Parathyroid Identification During Thyroidectomy: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

OBJECTIVE

Unintentional parathyroid gland resection during total thyroidectomy can result in permanent hypoparathyroidism and lifelong replacement therapy. Near infrared autofluorescence (NIRAF) imaging may aid intraoperative identification and preservation of the parathyroid glands. This article aims to review NIRAF's effectiveness in the prevention of post-operative hypoparathyroidism.

DESIGN

Systematic review and meta-analysis reported according to PRISMA guidelines.

METHODS

The electronic databases of MEDLINE, Embase and Cochrane were searched in September 2024. Included articles were randomised controlled trials (RCTs) that studied the use of NIRAF vs. dissection with no intraoperative aids in thyroidectomy. Meta-analysis was performed using a random-effects model. Primary outcomes were postoperative hypocalcaemia and permanent hypoparathyroidism.

RESULTS

Eight RCTs were included in the final analysis, comprising 1620 patients. Meta-analysis revealed patients undergoing thyroidectomy using NIRAF had a reduced risk of both post-operative hypocalcaemia (OR 0.56, 95% CI: 0.36-0.89, p = 0.01) and persistent hypoparathyroidism (OR 0.44, 95% CI: 0.22-0.89, p = 0.02).

CONCLUSIONS

NIRAF use in thyroidectomy reduces the risk of post-operative hypocalcaemia and post-operative hypoparathyroidism.

Impact of Intraoperative Interventions on Hypocalcemia Post-Total Thyroidectomy: A Meta-Analysis

ImportancePostoperative hypocalcemia following total thyroidectomy (TT) can significantly affect patients' quality of life. However, the most effective intraoperative interventions to mitigate this risk remain uncertain.ObjectiveTo assess the efficacy of parathyroid gland autotransplantation (PTA), near-infrared autofluorescence (NIRAF), and indocyanine green angiography (ICGA) in reducing postoperative hypocalcemia risk after TT.DesignMeta-analysis.SettingThis meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, utilizing data from PubMed, Embase, and the Cochrane Library, with searches conducted through February 2024.ParticipantsPatients undergoing TT with or without intraoperative interventions of PTA, NIRAF, ICGA, or a combined approach.InterventionsPTA, NIRAF, ICGA, or a combination of these methods.Main Outcome MeasuresIncidence of postoperative transient and permanent hypocalcemia.ResultsFrom 582 identified records, 32 studies, including 13,299 TT patients (6386 with benign and 6913 with malignant conditions), met the inclusion criteria. PTA was associated with a higher incidence of transient postoperative hypocalcemia (OR = 1.98; 95% CI: 1.42-2.77; I2 = 84%). Conversely, NIRAF (OR = 0.45; 95% CI: 0.35-0.57; I2 = 0%) and ICGA (OR = 0.22; 95% CI: 0.07-0.69; I2 = 0%) showed reduced incidences of transient hypocalcemia. The combined NIRAF and ICGA approach, evaluated in 2 studies, yielded inconclusive results (OR = 0.62; 95% CI: 0.28-1.37).Conclusions and RelevanceIntraoperative use of NIRAF and ICGA significantly decreased the incidence of transient hypocalcemia following TT, whereas PTA did not demonstrate similar efficacy. Minimal effects on permanent hypocalcemia were observed across interventions. Further research is necessary to clarify the effectiveness of the combined NIRAF and ICGA approach.

Camera-based near-infrared autofluorescence versus visual identification in total thyroidectomy for parathyroid function preservation: Systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Hypocalcemia is the most common postoperative complication of total thyroidectomy. Near-infrared autofluorescence (NIRAF) technology is a surgical adjunct that has been increasingly utilized with the aim of preventing postoperative hypocalcemia, but its clinical benefits have not yet been firmly established. The aim of this study was to assess the clinical benefit of utilizing NIRAF technology in patients undergoing total thyroidectomy.

METHODS

A systematic review and meta-analysis of randomized clinical trials was performed according to PRISMA guidelines.

RESULTS

Seven randomized clinical trials with 1437 patients (318 males, 22.13%) undergoing total thyroidectomy were included for analysis. Risk of postoperative hypocalcemia was reduced in the NIRAF arm (RR, 0.65; 95%CI, 0.50-0.84). Use of NIRAF was also associated with a reduction in the risk of permanent parathyroid dysfunction (RR, 0.46; 95%CI, 0.22-0.95) and inadvertent parathyroid gland resection (RR, 0.40; 95%CI, 0.26-0.60).

CONCLUSIONS

We present a systematic review and meta-analysis of randomized clinical trials examining the impact of NIRAF technology on preservation of parathyroid function. Our results suggest that use of camera-based NIRAF technology reduces the risk of postoperative hypocalcemia, permanent parathyroid dysfunction, and inadvertent parathyroid gland resection.

Exploring near-infrared autofluorescence properties in parathyroid tissue: an analysis of fresh and paraffin-embedded thyroidectomy specimens

Significance

Near-infrared autofluorescence (NIRAF) utilizes the natural autofluorescence of parathyroid glands (PGs) to improve their identification during thyroid surgeries, reducing the risk of inadvertent removal and subsequent complications such as hypoparathyroidism. This study evaluates NIRAF's effectiveness in real-world surgical settings, highlighting its potential to enhance surgical outcomes and patient safety.

Aim

We evaluate the effectiveness of NIRAF in detecting PGs during thyroidectomy and central neck dissection and investigate autofluorescence characteristics in both fresh and paraffin-embedded tissues.

Approach

We included 101 patients diagnosed with papillary thyroid cancer who underwent surgeries in 2022 and 2023. We assessed NIRAF's ability to locate PGs, confirmed via parathyroid hormone assays, and involved both junior and senior surgeons. We measured the accuracy, speed, and agreement levels of each method and analyzed autofluorescence persistence and variation over 10 years, alongside the expression of calcium-sensing receptor (CaSR) and vitamin D.

Results

NIRAF demonstrated a sensitivity of 89.5% and a negative predictive value of 89.1%. However, its specificity and positive predictive value (PPV) were 61.2% and 62.3%, respectively, which are considered lower. The kappa statistic indicated moderate to substantial agreement (kappa = 0.478; P < 0.001 ). Senior surgeons achieved high specificity (86.2%) and PPV (85.3%), with substantial agreement (kappa = 0.847; P < 0.001 ). In contrast, junior surgeons displayed the lowest kappa statistic among the groups, indicating minimal agreement (kappa = 0.381; P < 0.001 ). Common errors in NIRAF included interference from brown fat and eschar. In addition, paraffin-embedded samples retained stable autofluorescence over 10 years, showing no significant correlation with CaSR and vitamin D levels.

Conclusions

NIRAF is useful for PG identification in thyroid and neck surgeries, enhancing efficiency and reducing inadvertent PG removals. The stability of autofluorescence in paraffin samples suggests its long-term viability, with false positives providing insights for further improvements in NIRAF technology.

Intraoperative strategies in identification and functional protection of parathyroid glands for patients with thyroidectomy: a systematic review and network meta-analysis

BACKGROUND

This study aimed to assess the benefits and limitations of four intraoperative visualization of parathyroid gland (IVPG) strategies in the identification and functional protection of parathyroid glands (PGs).

METHODS

We searched PubMed, the Cochrane Central Register of Controlled Trials, CNKI, EMBASE, Web of Science and Google Scholar databases until 30 June 2023. Four IVPG strategies were composed of the naked eyes (NE) and three imaging strategies: autofluorescence (AF), indocyanine green fluorescence (ICGF), and carbon nanoparticles (CN). We performed a pairwise meta-analysis (PMA) for direct comparisons and a Bayesian network meta-analysis (NMA) for indirect comparisons.

RESULTS

A total of 29 eligible studies were included. According to NMA and PMA, AF had significantly lower rates of postoperative hypocalcemia and hypoparathyroidism, PG inadvertent resection, and PG auto-transplantation compared to NE, while had significantly higher rate of PG identification. CN showed significantly lower rates of postoperative hypocalcemia and hypoparathyroidism, and PG inadvertent resection compared to NE in PMA and NMA. ICGF showed a significantly higher rate of PG auto-transplantation compared to NE in PMA and AF in NMA. According to SUCRA values, AF showed the best advantage in reducing the rate of postoperative hypocalcemia (0.85) and PG inadvertent resection (0.89), and increasing the rate of PG identification (0.80). CN had the greatest advantage in reducing the rate of postoperative hypoparathyroidism (0.95). ICGF ranked the highest in the rate of PG auto-transplantation (0.98).

CONCLUSIONS

Three imaging strategies demonstrate significant superiority over NE in the intraoperative PG identification and functional protection. AF is the best strategy in reducing the incidence of postoperative hypocalcemia, increasing the rate of PG identification, and reducing the rate of PG inadvertent resection and auto-transplantation. ICGF has great value in assessing PG viability, leading to the trend towards PG auto-transplantation. CN is the best strategy in reducing the incidence of postoperative hypoparathyroidism.

Lower Rates of Hypocalcemia Following Near-Infrared Autofluorescence Use in Thyroidectomy: A Meta-Analysis of RCTs

BACKGROUND

Iatrogenic injury of the parathyroid glands is the most frequent complication after total thyroidectomy.

OBJECTIVE

To determine the effectiveness of near-infrared autofluorescence (NIRAF) in reducing postoperative hypocalcemia following total thyroidectomy.

METHODS

PubMed, Scopus, and Google Scholar databases were searched. Randomised trials reporting at least one hypocalcemia outcome following total thyroidectomy using NIRAF were included.

RESULTS

The qualitative data synthesis comprised 1363 patients from nine randomised studies, NIRAF arm = 636 cases and non-NIRAF arm = 637 cases. There was a statistically significant difference in the overall rate of hypocalcemia log(OR) = -0.7 [(-1.01, -0.40), M-H, REM, CI = 95%] and temporary hypocalcemia log(OR) = -0.8 [(-1.01, -0.59), M-H, REM, CI = 95%] favouring the NIRAF. The difference in the rate of permanent hypocalcemia log(OR) = -1.09 [(-2.34, 0.17), M-H, REM, CI = 95%] between the two arms was lower in the NIRAF arm but was not statistically significant.

CONCLUSIONS

NIRAF during total thyroidectomy helps in reducing postoperative hypocalcemia. Level of evidence-1.

Avoiding Complications of Thyroidectomy: Preservation of Parathyroid Glands

Preservation of functional parathyroid glands during thyroidectomy and central neck surgery is crucial to avoid the common but serious complication of hypoparathyroidism. The first requirement is a solid foundational knowledge of anatomy and embryology which then enables the surgeon to use meticulous anticipatory dissection with identification and preservation of blood supply to the parathyroids. When preservation of blood supply is not possible, autotransplantation should be performed. New technologies harnessing the natural phenomenon of parathyroid autofluorescence to detect parathyroid tissue and indocyanine green to perform angiography may lead to improved outcomes with low risk to patients.