What are the real rates of temporary hypoparathyroidism following thyroidectomy? It is a matter of definition: a systematic review

Permanent hypoparathyroidism following total thyroidectomy - Incidence and preventative strategies without imaging adjuncts

INTRODUCTION

Permanent hypoparathyroidism (pHypoPT) is the most common permanent complication of total thyroidectomy. We aim to describe the incidence and predictors of hypoparathyroidism in a consecutive series of patients treated in a high-volume centre and define strategies to reduce the risk of pHypoPT.

METHODS

1182 patients who underwent total thyroidectomy between April 2018 and June 2022 were analyzed. Temporary hypoparathyroidism (tHypoPT) was defined as PTH <0.4 ​pmol/L (<4 ​pg/mL) at day one post-operatively, or clinical or biochemical evidence of hypocalcemia. pHypoPT was defined as an ongoing need for calcitriol supplementation to maintain normocalcemia at 12 months. Symptomatic tHypoPT (OR 43.97, p ​< ​0.001) and number of parathyroid glands in the operative specimen (OR 2.31, p ​= ​0.022) were also significantly associated with pHypoPT.

RESULTS

Biochemical tHypoPT occurred in 205 (17.4 ​%) patients whilst pHypoPT occurred in 6 (0.5 ​%) patients. On multivariate analysis, parathyroid auto-transplantation (PA) independently reduced the risk of pHypoPT (OR 0.04, p ​= ​0.004).

CONCLUSIONS

The risk of pHypoPT after total thyroidectomy is 0.5 ​% when performed by high-volume surgeons. PA represents an important technique that reduces the risk of pHypoPT.

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.

Cost-Benefit Analysis of Intraoperative Autofluorescence for Parathyroid Identification

Importance

Hypoparathyroidism (hypoPT) is the most common complication post-total thyroidectomy and is associated with increased morbidity and mortality when chronic. Conventionally, the prevention of hypoPT has involved visual inspection of parathyroid glands; however, near-infrared autofluorescence detection systems have been recently used as adjuncts. These systems involve significant outlay and ongoing costs.

Objective

To evaluate the cost-effectiveness of autofluorescence for hypoPT prevention and to determine the chronic hypoPT rate at which this technology would become economically feasible.

Design, Setting, and Participants

In this cost-benefit analysis, a decision tree economic model was developed to compare thyroidectomies performed with autofluorescence to visual inspection only. All costs associated with conventional surgery, autofluorescence, and the costs of managing hypoPT were captured. Morbidity was defined in terms of disutility, quantified as quality-adjusted life-years, determined over a lifetime time horizon. The model was used to calculate the incremental cost-effectiveness ratio for autofluorescence-guided surgery and to identify determinants that influenced this ratio, and hence the economic feasibility of the use of autofluorescence. This study was based on the health care setting in Australia, in which more than 3500 thyroidectomies are performed annually. A probe-based autofluorescence detection system was used for analysis based on its availability in Australia. All costs were quantified in Australian dollars (A$) and were adjusted for 2024. The study data spanned from June 2022 to May 2023, and the data were analyzed in June 2023.

Results

The economic model analysis indicated that autofluorescence involved an additional cost of A $1024 (US $639) per surgery, offset by an increase in quality-adjusted life-years of 0.0080, resulting in an incremental cost-effectiveness ratio of A $128 234 (US $80 060). In Australia, it is generally assumed that interventions with a ratio of up to A $70 000 (US $43 703) may be considered cost-effective. Cost-effectiveness was most sensitive to a change in the overall hypoPT rate, chronic hypoPT rate, and the efficacy of autofluorescence. Autofluorescence-guided surgery achieved the cost-effectiveness threshold at a chronic hypoPT rate of greater than or equal to 5%.

Conclusions and Relevance

Although the use of autofluorescence involves significant costs, its economic feasibility for the prevention of postsurgical hypoPT is determined by the underlying chronic and overall hypoPT rate, as well as the efficacy of autofluorescence for the reduction of hypoPT. The findings of this cost-benefit analysis are relevant in determining the prioritization and allocation of finite health care resources.

Development and validation of risk prediction models for permanent hypocalcemia after total thyroidectomy in patients with papillary thyroid carcinoma

Hypocalcemia is a common complication and can be permanent in patients following total thyroidectomy (TT). The aim of this study was to identify factors associated with permanent hypocalcemia and to develop a validated risk prediction model for permanent hypocalcemia to assist surgeons in the appropriate follow-up of high-risk patients regarding supplemental therapy. We included data of 92 patients with papillary thyroid carcinoma (PTC) undergoing TT who were randomly allocated in a 7:3 ratio to a training set (n = 65) and validation set (n = 27). Univariate and multivariate logistic regression analyses revealed significant correlations of permanent hypocalcemia with parathyroid hormone (PTH) at postoperative month 1 (IM PTH), IM calcium (Ca), and IM phosphorus (P). These variables were constructed two models. Model 1 used the three indicators listed above; model 2 also included tumor, node, metastasis staging. The receiver operating characteristic (ROC) curve analysis showed that the areas under the curve (AUC) for models 1 and 2 were high for both the training set (0.905/0.913) and the validation set (0.894/0.800). Calibration curves showed good agreement between the incidence of permanent hypocalcemia estimated using the predictive models and the actual incidence. Model 1 may be more concise and convenient for clinical use.

Fluorescence intensity of parathyroid glands in thyroid and parathyroid surgery: a near-infrared autofluorescence study

Objective

Near-infrared autofluorescence (NIRAF) imaging shows promise in identifying parathyroid gland (PG) during surgery. However, the clinical application of NIRAF faces challenges due to the heterogeneous fluorescence intensity (FI) of PGs observed in different thyroid and parathyroid diseases. This study aimed to evaluate the effectiveness of NIRAF in PG detection and to analyze the FI of PGs in patients with various thyroid and parathyroid diseases.

Methods

A total of 105 patients undergoing thyroidectomy and parathyroidectomy were enrolled. Intraoperative NIRAF imaging was used to detect PGs, and the FI values were quantified using ImageJ software. Normal PGs were grouped according to the pathological results of ipsilateral thyroid diseases. Compare and analyze the FI values of normal and diseased PGs.

Results

A total of 239 PGs were detected during surgery. 225 PGs were identified by NIRAF. The NIRAF identification rate was significantly higher than visual identification (94.1% vs. 81.2%, p < 0.001). NIRAF demonstrated high performance in PG identification, with sensitivity, specificity, and positive predictive values and negative predictive values to predict PGs were 95.4%, 77.5%, 90.5% and 88.1%, respectively. The FI of PGs was higher in patients with papillary thyroid carcinoma (1.39 ± 0.21), follicular nodules of thyroid (1.45 ± 0.25), nodular thyroid gland (1.36 ± 0.19) than in those with hyperthyroidism (1.06 ± 0.28) and primary hyperparathyroidism (1.17 ± 0.23). Superior PGs in Stage I exhibited higher FI compared to PGs in Stage II (p = 0.025). In Stage II, the FI of inferior PGs was significantly higher than that of superior PGs (p < 0.001). The FI of PGs in both Stage I and II was significantly higher than in Stage III.

Conclusions

NIRAF demonstrates high efficiency in identifying PGs across various surgical stages, outperforming conventional visual identification. The FI of superior and inferior PGs exhibits significant variability across different intraoperative stages. Surgeons should exercise caution when identifying PGs in patients with primary hyperparathyroidism and hyperthyroidism, as these conditions are associated with lower FI compared to other thyroid diseases.

An outcome analysis of utilizing contrast-free near-infrared autofluorescence imaging in thyroid cancer surgery: a retrospective study

BACKGROUND

Hypoparathyroidism is the most common complication of thyroid surgery. The best way to assume normal parathyroid gland (PTG) function is to preserve them in situ, undamaged. Near-infrared autofluorescence (NIRAF)-imaging has been introduced as a potentially useful adjunct in thyroid surgery.

OBJECTIVE

To assess the surgical outcomes of NIRAF-imaging utility in thyroid surgery.

METHODS

The clinical records of patients who underwent surgery for papillary thyroid carcinoma (PTC) in a 7-month period were retrospectively reviewed. The primary endpoint was to assess NIRAF's impact on postoperative hypoparathyroidism. Secondary endpoints included its impact in preventing inadvertent PTG resection, time to resolution of postoperative hypoparathyroidism, and additional benefits in therapeutic central compartment neck dissection (tCCND).

RESULTS

Fifty consecutive patients underwent surgery for PTC. Total thyroidectomy was performed in 42 patients. Whereas concomitant tCCND was performed in 8 patients. PTG-detection rate was 93% for NIRAF versus 87% for the surgeon (p = 0.04). NIRAF prevented inadvertent resection of 16 PTGs (p < 0.001). In tCCND, the detection rate of NIRAF was 100% versus 81% for the surgeon (p < 0.01). The rate of transient hypoparathyroidism applying NIRAF was 12% versus 15% (historical cohort) (p = 0.6). However, a significantly prompter resolution of hypoparathyroidism was demonstrated using NIRAF (average time of 2.7 weeks vs. 12.3 weeks; p < 0.0001).

CONCLUSION

Although NIRAF did not significantly minimize the overall risk of postoperative transient hypoparathyroidism, it demonstrated a trend toward improvement. It also led to prompter resolution of hypoparathyroidism and lowered the risk for inadvertent PTG resection. Therefore, NIRAF seems to be a promising surgical adjunct.

The outcomes of parathyroid gland autotransplantation during thyroid surgery: a systematic review, meta-analysis and trial sequential analysis

PURPOSE

Thyroidectomy is the treatment of choice for malignant thyroid diseases as well as for benign conditions who cannot be treated medically. The most common complication following thyroidectomy is hypocalcaemia and hypoparathyroidism that usually results from accidental damage or removal of one or more parathyroid glands. Parathyroid gland autotransplantation has been one of the most common intraoperative strategies applied to tackle this problem. The aim of this study is to assess whether parathyroid auto trasnplantation is associated with a decrease in postoperative hypoparathyroidism following thyroidectomy.

METHODS

We conducted a thorough systematic review and meta-analysis of relevant studies published up to February 2024 in MEDLINE, Scopus, Embase and Cochrane Library databases. We compared the incidence of postoperative hypoparathyroidism between the group of patients who underwent autotransplantation and the patients were the parathyroid glands were preserved in situ. A trial sequential analysis was performed subsequently to confirm the findings.

RESULTS

Eighteen studies fulfilled all the inclusion criteria and were ultimately included in our study. The total number of patients was 8,182 with 4,029 receiving parathyroid gland autotransplantation. Autotransplantation was associated with a higher incidence of immediate (within 24 h) and transient hypoparathyroidism (RR 1.58, 1.45-1.73, CI 95%, p < 0.00 and RR 1.60, 1.47-1.76, CI 95%, p < 0.001, respectively). However, it did not affect the rate of permanent postoperative hypoparathyroidism (RR 0.85, 0.51-1.41, CI 95%, p = 0.54). The subsequent trial sequential analysis confirmed these findings.

CONCLUSION

Parathyroid autotransplantation does not lead to a decrease in the rate of permanent post-thyroidectomy hypoparathyroidism. The most important factor to decrease its incidence remains the accurate identification and preservation of the parathyroid glands intraoperatively.

Risk factors of transient and permanent hypoparathyroidism after thyroidectomy: a systematic review and meta-analysis

BACKGROUND

Postoperative hypoparathyroidism (hypoPT) is a common complication following thyroid surgery. However, current research findings on the risk factors for post-thyroid surgery hypoPT are not entirely consistent, and the same risk factors may have different impacts on transient and permanent hypoPT. Therefore, there is a need for a comprehensive study to summarize and explore the risk factors for both transient and permanent hypoPT after thyroid surgery.

MATERIALS AND METHODS

Two databases (PubMed and Embase) were searched from inception to 2024. The Newcastle-Ottawa Scale was used to rate study quality. Pooled odds ratios were used to calculate the relationship of each risk factor with transient and permanent hypoPT. Subgroup analyses were conducted for hypoPT with different definition-time (6 or 12 months). Publication bias was assessed using Begg's test and Egger's test.

RESULTS

A total of 19 risk factors from the 93 studies were included in the analysis. Among them, sex and parathyroid autotransplantation were the most frequently reported risk factors. Meta-analysis demonstrated that sex (female vs. male), cN stage, central neck dissection, lateral neck dissection, extent of central neck dissection (bilateral vs. unilateral), surgery [total thyroidectomy (TT) vs. lobectomy], surgery type (TT vs. sub-TT), incidental parathyroidectomy, and pathology (cancer vs. benign) were significantly associated with transient and permanent hypoPT. Preoperative calcium and parathyroid autotransplantation were only identified as risk factors for transient hypoPT, while preoperative PTH was a protective factor. Additionally, node metastasis and parathyroid in specimen were associated with permanent hypoPT.

CONCLUSION

The highest risk of hypoPT occurs in female thyroid cancer patients with lymph node metastasis undergoing TT combined with neck dissection. The key to preventing postoperative hypoPT lies in the selection of surgical approach and intraoperative protection.

Active surveillance versus immediate surgery in the management of low-risk papillary thyroid microcarcinoma: comparison of long-term costs in Brazil

Objective

To compare the long-term medical costs of active surveillance (AS), partial thyroidectomy (PT), and total thyroidectomy (TT) in patients with low-risk papillary thyroid microcarcinoma (PTMC) receiving care covered by the Brazilian Public Health System.

Materials and methods

After reviewing AS cohorts and our own data, we created a model of AS, PT, and TT flow care for low-risk PTMC over 10, 20, and 30 years. The medical costs included those associated with diagnosis, surgery, and follow-up. We considered that 13.3% of the patients on AS would require surgery after a mean of 21.3 months, 4% undergoing TT would develop permanent hypoparathyroidism, and 43% undergoing PT would develop hypothyroidism.

Results

The most economical alternative was AS. The costs of TT per patient were higher than those of AS by 182.8% over 10 years (866.89 versus 306.49 US dollars [USD], respectively), by 152.9% over 20 years (1,023.66 versus 404.73 USD, respectively), and by 134.7% over 30 years (1,180.42 versus 502.96 USD, respectively). The costs of PT per patient were higher than those of AS by 16.0% over 10 years (355.66 versus 306.49 USD, respectively), by 16.9% over 20 years (473.41 versus 404.73 USD, respectively), and by 17.5% over 30 years (591.17 versus 502.96 USD, respectively).

Conclusion

The AS approach was less costly than immediate surgery throughout 30 years of follow-up. Hence, the implementation of AS in Brazil should not be hindered by cost considerations.

An automatic parathyroid recognition and segmentation model based on deep learning of near-infrared autofluorescence imaging

INTRODUCTION

Near-infrared autofluorescence imaging (NIFI) can be used to identify parathyroid gland (PG) during surgery. The purpose of the study is to establish a new model, help surgeons better identify, and protect PGs.

METHODS

Five hundred and twenty three NIFI images were selected. The PGs were recorded by NIFI and marked with artificial intelligence (AI) model. The recognition rate for PGs was calculated. Analyze the differences between surgeons of different years of experience and AI recognition, and evaluate the diagnostic and therapeutic efficacy of AI model.

RESULTS

Our model achieved 83.5% precision and 57.8% recall in the internal validation set. The visual recognition rate of AI model was 85.2% and 82.4% on internal and external sets. The PG recognition rate of AI model is higher than that of junior surgeons (p < 0.05).

CONCLUSIONS

This AI model will help surgeons identify PGs, and develop their learning ability and self-confidence.

Investigating the optimal parathyroid autotransplantation strategy in transareolar endoscopic thyroidectomy: A retrospective cohort study

BACKGROUND

There is ongoing debate about whether intraoperative parathyroid autotransplantation effectively prevents permanent hypoparathyroidism after thyroidectomy. This study aims to examine its impact on postoperative parathyroid function and determine the best autotransplantation strategy.

METHODS

A retrospective analysis was conducted on 194 patients who underwent total thyroidectomy with central lymph node dissection (CLND) for papillary thyroid carcinoma (PTC). Patients were divided into four groups based on the number of parathyroid autotransplants during surgery: Group 1 (none, n = 43), Group 2 (1 transplant, n = 60), Group 3 (2 transplants, n = 67), and Group 4 (3 transplants, n = 24). Various clinical parameters were collected and compared among the groups.

RESULTS

Parathyroid autotransplantation was identified as a risk factor for temporary hypoparathyroidism (OR: 1.74; 95% CI: 1.27-2.39, P = 0.001) and a protective factor for permanent hypoparathyroidism (OR: 0.27; 95% CI: 0.14-0.55, P < 0.001). At 12 months postoperative, systemic parathyroid hormone (PTH) levels increased progressively from Groups 1 to 4, with significant differences observed only between Group 1 and Group 2 (P < 0.02). Difference values in systemic PTH levels between Month 1 and Day 1 postoperative increased progressively from Groups 1 to 4, with statistically significant differences observed between adjacent groups (P < 0.02). The number of dissected positive lymph nodes increased progressively across the four groups, showing statistical differences (P < 0.02).

CONCLUSION

Parathyroid autotransplantation can prevent permanent hypoparathyroidism. Additionally, we recommend preserving parathyroids in situ whenever possible. If autotransplantation is required, it should involve no more than two glands.

Impact of autofluorescence for detection of parathyroid glands during thyroidectomy on postoperative parathyroid hormone levels: parallel multicentre randomized clinical trial

BACKGROUND

Techniques for autofluorescence have been introduced to visualize the parathyroid glands during surgery and to reduce hypoparathyroidism after thyroidectomy.

METHODS

This parallel multicentre RCT investigated the use of Fluobeam® LX to visualize the parathyroid glands by autofluorescence during total thyroidectomy compared with no use. There was no restriction on the indication for surgery. Patients were randomized 1 : 1 and were blinded to the group allocation. The hypothesis was that autofluorescence enables identification and protection of the parathyroid glands during thyroidectomy. The primary endpoint was the rate of low parathyroid hormone (PTH) levels the day after surgery.

RESULTS

Some 535 patients were randomized, and 486 patients received an intervention according to the study protocol, 246 in the Fluobeam® LX group and 240 in the control group. Some 64 patients (26.0 per cent) in the Fluobeam® LX group and 77 (32.1 per cent) in the control group had low levels of PTH after thyroidectomy (P = 0.141; relative risk (RR) 0.81, 95 per cent c.i. 0.61 to 1.07). Subanalysis of 174 patients undergoing central lymph node clearance showed that 15 of 82 (18 per cent) in the Fluobeam® LX group and 31 of 92 (33 per cent) in the control group had low levels of PTH on postoperative day 1 (P = 0.021; RR 0.54, 0.31 to 0.93). More parathyroid glands were identified during operation in patients who had surgery with Fluobeam® LX, and fewer parathyroid glands in the surgical specimen on definitive histopathology. No specific harm related to the use of Fluobeam® LX was reported.

CONCLUSION

The use of autofluorescence during thyroidectomy did not reduce the rate of low PTH levels on postoperative day 1 in the whole group of patients. It did, however, reduce the rate in a subgroup of patients. Registration number: NCT04509011 (http://www.clinicaltrials.gov).

Minimally Invasive Treatments of Benign Thyroid Nodules: A Network Meta-Analysis of Short-Term Outcomes

Background: Image-guided thermal ablation interventions are novel thermal-based modalities used for the treatment of benign thyroid nodules. Methods: We conducted a systematic review and a Bayesian network meta-analysis, examining studies using thermal ablation interventions in the treatment of benign nodular thyroid disease (PROSPERO CRD42022367680). The primary endpoints included volume reduction rate (VRR), and symptomatic score and cosmetic score improvement. Secondary endpoints included vocal disturbances, laryngeal nerve palsy, hypothyroidism, and nodular regrowth (defined by increased nodular volume of >50% for thermal ablation or new nodules arising in remaining thyroid tissue conventional surgery [CS]). Results: We included 16 studies (3 randomized controlled trials [RCTs] and 13 comparative case series), describing radiofrequency ablation (RFA), laser ablation (LA), microwave ablation (MWA), high-intensity focus ultrasound (HIFU), and CS, respectively. The review included data from 4112 patients followed for a mean of 11.9 months. Meta-analyses showed no significant differences among RFA, LA, MWA, HIFU, and CS regarding any of the primary endpoints of VRR, symptomatic score, and cosmetic score. In examining the surface under the cumulative ranking area (SUCRA) ranking, CS (SUCRA, 98.49), LA (SUCRA, 51.58), and MWA (SUCRA, 57.0) were identified as the three interventions that were most likely to result in the largest VRR, symptomatic and cosmetic score reduction. RFA, relative risk (RR) 0.19 [95% credibility interval (CI): 0.06 to 0.48], LA RR 0.23 [CI: 0.06 to 0.79], and MWA RR 0.25 [CI: 0.09 to 0.60] were associated with the greatest reduction in risk for postintervention vocal complications compared with CS, with RFA (SUCRA, 61.62) being ranked as the highest in safety. RFA RR 0.05 [CI: 0.00 to 0.40] and MWA RR 0.16 [CI: 0.02 to 0.73] were associated with a reduced risk of transient laryngeal nerve injury compared with CS. RFA RR 0.00 [CI: 0.00 to 0.00] and MWA RR 0.00 [CI: 0.00 to 0.03] were associated with a reduced risk of hypothyroidism occurrence compared with CS, with RFA (SUCRA, 99.86) yielding the highest safety ranking. RFA was associated with a reduced risk for nodular regrowth RR 0.09 [CI: 0.00 to 0.85], compared with CS. Conclusion: We have comprehensively reviewed the published literature on the efficacy and safety of thermal ablation modalities for benign thyroid nodules. Important research gaps remain regarding a paucity of both long-term data and high-quality RCTs.

Prevention of hypocalcemia and hypoparathyroidism after total thyroidectomy. Recommendations of the Francophone Association of Endocrine Surgery (AFCE) with the French Society of Endocrinology (SFE) and the French Society of Nuclear Medicine (SFMN)

Postoperative hypoparathyroidism, resulting from removal and/or devascularization of one or more parathyroid glands, is a feared complication of total thyroidectomy. Two forms, which are distinguished by their frequency, their time to onset and their duration as well as by their presentation, must be individualized: early postoperative hypocalcemia, often secondary to early hypoparathyroidism is a frequent and often transient situation occurring within the first days after surgery; permanent hypoparathyroidism, which is rarer, manifests when parathyroid function remains impaired for more than six months after surgery. Because of their severity, these conditions must be known and ideally prevented during total thyroidectomy. The objective of this article is to provide surgeons with practical recommendations for the prevention, diagnosis, and treatment of hypoparathyroidism after total thyroidectomy. These recommendations, which are the fruit of a medico-surgical consensus, were developed by the Francophone Association of Endocrine Surgery (AFCE), the French Society of Endocrinology (SFE) and the French Society of Nuclear Medicine and Molecular Imaging. (SFMN). The content, grade and level of evidence for each recommendation was decided after consultation within a panel of experts, based on an analysis of recent literature.

Indocyanine green angiography-guided thyroidectomy versus conventional thyroidectomy for preserving parathyroid function: study protocol for a randomized single-blind controlled trial

Introduction

Angiography with indocyanine green (ICG) fluorescence performed before thyroidectomy would allow identification of the vascularization of parathyroid glands, maximizing efforts for preserving functioning glands intraoperatively. The rationale of the study was based on the hypothesis that showing the vascular pattern of the parathyroid glands by means of ICG angiography before performing the thyroidectomy could prevent permanent hypoparathyroidism.

Methods and analysis

We propose a randomized single-blind controlled and multicenter clinical trial to assess the efficacy and safety of ICG angiography-guided thyroidectomy to identify the vascular pattern of the parathyroid glands versus conventional thyroidectomy in patients scheduled for elective total thyroidectomy. Patients will be randomized 1:1 to ICG angiography-guided thyroidectomy (experimental group) or conventional thyroidectomy (control group). Patients in the experimental group will undergo ICG angiography before thyroidectomy to identify the feeding vessels of the parathyroid glands and then, post-thyroidectomy ICG angiography to predict immediate parathyroid gland function by scoring the degree of fluorescence of the glands. Patients in the control group will undergo post-thyroidectomy ICG angiography only. The primary outcome measure will be the rate of patients with permanent hypoparathyroidism. Secondary outcome measures will be rate of postoperative hypoparathyroidism, the percentage of well vascularized parathyroid glands remaining in situ, the levels of iPTH and serum calcium after surgery and the influence of the type of vascular pattern of the parathyroid glands over these outcomes, as well as the safety profile of ICG angiography.

Discussion

The results will contribute to adopt a new surgical strategy based on intraoperative ICG angiography before performing total thyroidectomy, according to which the rate of permanent hypoparathyroidism could be substantially reduced.

Clinical trial registration

ClinicalTrials.gov. identifier NCT05573828.

Serum PTH at 4 h after total thyroidectomy as a predictor of hypocalcemia: a prospective time frame analysis in search of evidence

INTRODUCTION

There has not been a universal agreement about the timings and the threshold level of PTH that can accurately predict the risk of hypocalcemia. Our study aimed to investigate the changes in the serum PTH levels at various time intervals and correlate it with the development of subsequent hypocalcemia.

MATERIALS AND METHODS

All patients had a pre-operative serum PTH done and were again assessed intra-operatively, at 4 h, 24 h, 72 h, and 1 month after the thyroid surgery. Absolute serum PTH value at various time points, absolute change in serum PTH values compared to pre-operative level, and relative change (percentage change) in serum PTH values compared with pre-operative levels were used to predict post-operative Hypocalcemia.

RESULTS

49 patients were included in the study. The sensitivity and negative predictive value was 100% for serum PTH at 4 h. There was a statistically significant difference between the groups that required calcium supplementation versus the group that did not require it. The maximum relative reduction in serum PTH value with respect to the pre-operative level occurred at 4 h in the calcium supplement required group which was 82.5%. Use of combination of 4 h serum PTH and relative change at 4 h yielded the best results.

CONCLUSION

A combination of absolute serum PTH level at 4 h and the relative decline in serum PTH at 4 h has the highest diagnostic accuracy. The use of this combined parameter helps to reliably predict patients who would require supplementation.

Incremental value of magnification and indocyanine green for parathyroid preservation in thyroid surgery

BACKGROUND

To assess the promise of surgical magnification and of intraoperative indocyanine green (ICG) assisted near-infrared fluorescence (NIRF) in improving parathyroid identification and viability assessment during thyroidectomy.

METHODS

Prospective comparative study. Parathyroid gland identification sequentially assessed by naked eye, surgical microscopy, and by NIRF imaging following ICG administration (5 mgIV). Parathyroid perfusion/vitality reassessed end-surgery by ICG-NIRF.

RESULTS

An expected total of 104 parathyroid glands were assessed in 35 patients (17 total-thyroidectomy, 18 hemi-thyroidectomy). 54/104 (51.9%) were identified by naked eye, and sequentially greater numbers identified by microscope magnification (n = 61; 58.7%; p = 0.33), and by ICG-NIRF (n = 72; 69.2%; p = 0.01). ICG-NIRF detected additional parathyroid glands in 16/35 patients (45.7%). Confident identification of at least one parathyroid remained unachieved in 5/35 by naked eye, in 4/35 by microscopic magnification, and in no patient by ICG-NIRF. ICG-NIRF indicated end-of-surgery devascularization in 12/72 glands and informed decisions regarding gland implantation.

CONCLUSION

Significantly greater parathyroid glands are identified and preserved with surgical magnification and with ICG-NIRF. Both techniques merit routine adoption for thyroidectomy.

Frequency and Risk Factors of Permanent Hypoparathyroidism After Total Thyroidectomy: An Experience at a Tertiary Care Hospital in Pakistan

OBJECTIVES

Thyroid surgeries are among the most common operations performed in the world. Hypocalcemia following total thyroidectomy (TT) is a common complication that is sometimes difficult to correct. This study aims to determine the frequency of hypocalcemia and permanent hypoparathyroidism (PtHPT) following TT.

METHODS

A total of 363 patient records were reviewed who underwent TT for any reason. Thirty-eight patients did not have a follow-up in the clinic in the postoperative period and were excluded from the final analysis with the final sample as 325. For patients who developed hypocalcemia during the postoperative hospital stay, their lowest calcium levels were recorded and medical records were reviewed for the period of one year for the requirement of oral calcium and active form of vitamin D (calcitriol or alpha calcidiol) in the outpatient setting. Patients who required calcium and vitamin D supplementation for up to 1 year were labeled as having PtHPT. Risk factors were analyzed among those who developed PtHPT.

RESULTS

From a total of 325 patients postoperative hypocalcemia developed in 163 (50.2%) patients, and 162 (49.8%) patients remained normocalcemic. Permanent hypoparathyroidism was found in 42(12.9%) patients and transient HPT in 121 (37.2%). Age, severe postoperative hypocalcemia (PoHC), and readmission for hypocalcemia were independent risk factors for PtHPT.

CONCLUSIONS

Transient hypoparathyroidism (THPT) is common in our setup. Patients who develop severe hypocalcemia postoperatively and need readmission should be closely followed for the development of PtHPT.

Risk Factors for Hypoparathyroidism after Thyroid Surgery: A Single-Center Study

BACKGROUND

Hypoparathyroidism is one of the most common complications after thyroidectomy. This study evaluated the incidence and potential risk factors for postoperative hypoparathyroidism after thyroid surgical procedures in a single high-volume center.

METHODS

In this retrospective study, in all patients undergoing thyroid surgery from 2018 to 2021, a 6 h postoperative parathyroid hormone level (PTH) was evaluated. Patients were divided into two groups based on 6 h postoperative PTH levels (≤12 and >12 pg/mL).

RESULTS

A total of 734 patients were enrolled in this study. Most patients (702, 95.6%) underwent a total thyroidectomy, while 32 patients underwent a lobectomy (4.4%). A total of 230 patients (31.3%) had a postoperative PTH level of <12 pg/mL. Postoperative temporary hypoparathyroidism was more frequently associated with female sex, age < 40 y, neck dissection, the yield of lymph node dissection, and incidental parathyroidectomy. Incidental parathyroidectomy was reported in 122 patients (16.6%) and was correlated with thyroid cancer and neck dissection.

CONCLUSIONS

Young patients undergoing neck dissection and with incidental parathyroidectomy have the highest risk of postoperative hypoparathyroidism after thyroid surgery. However, incidental parathyroidectomy did not necessarily correlate with postoperative hypocalcemia, suggesting that the pathogenesis of this complication is multifactorial and may include an impaired blood supply to parathyroid glands during thyroid surgery.

Analysis of Unmet Information Needs Among Patients With Thyroid Cancer

Importance

Counseling prior to thyroid cancer (TC) treatment is an essential component of informed consent. An informed patient affects treatment-related expectations and patient engagement, factors that contribute significantly to patient-reported quality-of-life outcomes.

Objective

To describe experiences with pretreatment counseling among survivors of TC and to test factors associated with self-reported treatment meeting expectations.

Design, Setting, and Participants

A cross-sectional survey was administered between October 18, 2019, and February 8, 2020, to members of ThyCa: Thyroid Cancer Survivors' Association Inc, and to individuals accessing the public-facing ThyCa website. Survey respondents were asked 55 questions, including 4 free-text questions and 2 multiple-choice questions about pretreatment counseling.

Main Outcomes and Measures

Respondents self-reported (1) their unmet information needs, (2) rates of treatment meeting expectations, and (3) rates of treatment understanding. A mixed-methods analysis was performed, including qualitative content analysis of free-text responses and multivariable logistic regression of factors associated with self-reported levels of treatment meeting expectations.

Results

Of the 1412 survey respondents, 1249 were women (88.4%). The median age at diagnosis was 48 years (range, 18-85 years), and the median age at the time of survey completion was 60 years (range, 18-87 years). A total of 1259 respondents (89.2%) provided free-text responses to the question, "What would you tell someone newly diagnosed with your same condition?" Of these individuals, 526 (37.2%) reported inadequate pretreatment plan understanding and 578 (40.9%) reported that their treatment experience did not meet their expectations. Treatment met expectations for only 95 respondents (18.1%) reporting an inadequate pretreatment plan understanding. Of the 526 survivors of TC reporting a lack of understanding, 473 (90.0%) provided additional textual comments, most commonly in the categories of postoperative treatment, surveillance, and treatment effects. On multivariable logistic regression, self-reported failure to have an understanding of TC treatment was independently associated with failure of treatment to meet expectations (odds ratio, 5.1 [95% CI, 3.7-6.9]). Patients reporting a full understanding of their treatment plan were 5-fold more likely to indicate that their initial treatment experience was on par with expectations, independent of reported postoperative complications, age, sex, and other potential confounders.

Conclusions and Relevance

In this survey study, a substantial proportion of survivors of TC reported inadequate pretreatment understanding. This gap in understanding was associated with high levels of self-reported failure of treatment to meet expectations, which in turn is associated in other studies with poorer patient-reported quality-of-life outcomes. These outcomes may be improved by addressing gaps in patient understanding so expectations more closely match TC diagnosis and treatment pathways.

An improved method of searching inferior parathyroid gland for the patients with papillary thyroid carcinoma based on a retrospective study

Objective

Many surgeons knew the importance of parathyroid gland (PG) in the thyroid surgery, but it was even more difficult to be protected. This study aimed at evaluating the effectiveness of the improved method of searching inferior parathyroid gland (IPG).

Methods

213 patients were enrolled and divided into test and control groups according to different methods of searching IPG in the surgery. Consequently, we compared the surgical outcome parameters between the two groups, including the operative time, numbers of PG identifying (PG protection in situ, PG auto-transplantation, and PG accidental removal), numbers of the total lymph node (LN) and metastatic LN, parathyroid hormone (PTH), transient hypoparathyroidism, transient recurrent laryngeal nerve palsy, and postoperative bleeding.

Results

We identified 194 (194/196, 98.98%) and 215 (215/230, 93.48%) PGs in the test group and control group, respectively, and there was a significant difference (P = 0.005), and this result was due to IPG identification differences (96/98, 97.96% vs. 100/115, 86.96%, P = 0.004). Meanwhile, there was a lower ratio of IPG auto-transplantation in the test group compared with that in the control group (46.94% vs. 64.35%, P = 0.013). Serum PTH one day after the operation was 3.65 ± 1.86 vs. 2.96 ± 1.64 (P = 0.043) but with no difference at 6 months. There were no differences in metastatic LN and recurrent laryngeal nerve palsy between two groups.

Conclusion

The improved method of searching IPG was simple, efficient, and safe, which was easy to be implemented for searching IPG and protecting it well.

The Role of Carbon Nanoparticles in Lymph Node Dissection and Parathyroid Gland Preservation during Surgery for Thyroid Cancer: A Systematic Review and Meta-Analysis

Thyroid cancer is the most common endocrine malignancy with an increasing incidence over the past few years. Surgery is considered the primary therapeutic option, which often involves lymph node dissection. The aim of this study was to assess the role of carbon nanoparticles, a novel agent, in thyroid cancer surgery. For that purpose, we conducted a systematic review of the literature on MEDLINE, EMBASE, Scopus, Cochrane and Google Scholar databases from 1 January 2002 to 31 January 2022. Ultimately, 20 articles with a total number of 2920 patients were included in the analysis. The outcome of the analysis showed that the use of carbon nanoparticles is associated with a higher number of harvested lymph nodes (WMD, 1.47, 95% CI, 1.13 to 1.82, p < 0.001) and a lower rate of accidental parathyroid gland removal (OR 0.34, CI 95% 0.24 to 0.50, p < 0.001). Based on these results, we suggest that carbon nanoparticles are applied in thyroid cancer surgery on a wider scale, so that these findings can be confirmed by future research on the subject.

Clinical application of parathyroid autotransplantation in endoscopic radical resection of thyroid carcinoma

Purpose

This study aimed to examine the effect of selective inferior parathyroid gland autotransplantation on central lymph node dissection(CLND) and incidence of postoperative hypoparathyroidism in patients undergoing endoscopic radical resection of thyroid carcinoma.

Methods

The data of 310 patients undergoing endoscopic radical resection of thyroid carcinoma will be retrospectively analyzed. The patients will be divided into the experimental group and the control group according to whether they combined with parathyroid autotransplantation. Statistics of the incidence rate of postoperative hypoparathyroidism, the concentration of PTH and Calcium in the systemic circulation at different time points in the two groups, the concentration of PTH in the cubital fossa vein in the transplantation region in the experimental group, and the number of central lymph nodes and positive lymph nodes dissection will be carried out.

Results

The incidence rate of temporary and permanent hypoparathyroidism in the experimental group was 33.75% and 0.625%, respectively, and in the control group was 22% and 5%, respectively; its difference was statistically significant (X^{2 =} 10.255, P=0.006). Parathyroid autotransplantation increased incidence of transient hypoparathyroidism (OR, 1.806; Cl, 1.088-2.998; P=0.022), and lower incidence of permanent hypoparathyroidism (OR, 0.112; Cl, 0.014-0.904; P=0.040). The diameters of thyroid cancer nodules was not associated with the occurrence of transient hypoparathyroidism (OR, 0.769; Cl, 0.467-1.265; P=0.301) or permanent hypoparathyroidism (OR, 1.434; Cl, 0.316-6.515; P=0.641). Comparison of systemic circulation PTH, between the two groups showed that the PTH of patients in the experimental group was higher than that in the control group from 1 week to 12 months after the operation, and the difference was statistically significant (P<0.05). In the experimental group, from 1 week to 12 months after surgery, PTH concentrations was significantly higher in the cubital fossa of the transplantation side than in the contralateral side, and the differences were statistically significant (P<0.05). The mean number of central lymph node dissected per patient was significantly higher in the experimental group (7.94 ± 3.03 vs. 6.99 ± 2.86; P <0.05); The mean number of positive nodes per patient was significantly higher in the experimental group (3.16 ± 1.86 vs. 2.53 ± 1.59; P <0.05).

Conclusions

In endoscopic radical resection of thyroid carcinoma, parathyroid autotransplantation is more beneficial to postoperative parathyroid glands function recovery, effectively preventing postoperative permanent hypoparathyroidism and realizing more thorough CLND.

How Long Does It Take to Regain Normocalcaemia in the Event of Postsurgical Hypoparathyroidism? A Detailed Time Course Analysis

Background: Postsurgical hypoparathyroidism (PH) is the most common side effect of bilateral thyroid resections. Data regarding the time course of recovery from PH are currently unavailable. Therefore, a detailed analysis of the time course of PH recovery and conditions associated with rapid recovery was conducted. Methods: This is a retrospective analysis of prospectively documented data. Patients with biochemical signs of PH or need for calcium supplementation were followed-up for 12 months. Logistic regression analyses were used to identify covariates of early as opposed to late recovery from PH. Results: There were 1097 thyroid resections performed from 06/2015 to 07/2016 with n = 143 PH. Median recovery time was 8 weeks and six patients (1.1% of total thyroid resections) required calcium supplementation > 12 months. Recovery of PH within 4 and 12 weeks was characterized by high PTH levels on the first postoperative day (4 weeks: OR 1.13, 95% CI 1.06−1.20; 12 weeks: OR 1.08, 95%CI 1.01−1.16). Visualization of all PTGs emerged as an independent predictor of recovery within 12 months (OR 2.32, 95% CI 1.01−4.93) and 24 weeks (OR 2.69, 95% CI 1.08−6.69). Conclusion: In the setting of specialized high-volume endocrine surgery, permanent PH is rare. However, every second patient will require more than 2 months of continued medical surveillance. Early recovery was associated with only moderately decreased postsurgical PTH-levels. Successful late recovery appeared to be associated with the number of parathyroid glands visualized during surgery.

Establishing a predictive model of hypoparathyroidism after total thyroidectomy and central lymph node dissection for postoperative calcium supplementation selectively

Background

The core goal of this article is to find some meaningful risk factors that can affect the postoperative hypoparathyroidism of thyroid cancer, create an effective prediction model on this basis, and use it to selectively implement routine prophylactic calcium supplementation for patients after thyroid carcinoma surgery.

Methods

The clinicopathological characteristics of patients with papillary thyroid carcinoma (PTC) who underwent conventional bilateral total thyroidectomy (TT) + bilateral central lymph node dissection from January 2020 to August 2021 in the Affiliated Hospital of Nantong University were retrospectively analyzed. Firstly, this study analyzed the relationship between postoperative hypocalcemia and hypoparathyroidism. Then, we included many potential risk factors such as gender, age, body mass index (BMI), lateral lymph node dissection (LLND) and so on and also performed univariate and multivariate analysis of the independent risk factors for postoperative hypoparathyroidism in patients, and established a predictive scoring model.

Results

Among the 401 patients with PTC, 50.1% developed postoperative hypoparathyroidism. There was significant difference in serum calcium concentration between normal parathyroid group and hypoparathyroidism group after thyroid carcinoma surgery. BMI <24 kg/m², lateral lymph node dissection, multifocality, and extrathyroidal extension (ETE) were all identified as independent risk factors for postoperative hypoparathyroidism. Based on these independent risk factors, a nine-point risk scoring model was created to firstly assess the postoperative parathyroid function status of patients and then to determine whether routine prophylactic calcium supplementation is needed. Importantly, the area under the curve (AUC) of the risk scoring model is equal to 0.979.

Conclusions

At present, prophylactic calcium supplementation after thyroid carcinoma surgery is a controversial postoperative treatment. It should be selectively implemented for high-risk patients with hypoparathyroidism after surgery. Routine prophylactic calcium supplementation is recommended for PTC patients with a score greater than or equal to 5, although there are no clinical symptoms of postoperative hypocalcemia caused by hypoparathyroidism. However, prophylactic calcium supplementation is not recommended for patients with PTC with a score of less than 5; if the patient develops hypocalcemia at the later stage, therapeutic calcium supplementation can then be implemented.

Robotic bilateral axillo-breast versus endoscopic bilateral areola thyroidectomy outcomes of 757 patients

BACKGROUND

Remote endoscopic thyroidectomy (ET) and robotic thyroidectomy (RT) seem to be beneficial in selected situations to avoid anterior neck scars. There are limited data in the literature to determine whether RT via a bilateral axillo-breast approach (RT-BABA) is superior to ET via a bilateral areolar approach (ET-BAA). Therefore, the aim of this study was to evaluate the surgical outcomes of RT-BABA versus ET-BAA.

METHODS

Between May 2013 and May 2022, 757 patients who underwent RT-BABA or ET-BAA at a high-volume Chinese thyroid center were included. Intraoperative and postoperative outcome parameters were collected and retrospectively analyzed. The moving average method was used to evaluate the learning curve.

RESULTS

The proportion of patients older than 45 years was greater in the RT group than in the ET group (14.8% vs. 7.4%, p < 0.001). The percentage of overweight patients was greater in the RT group (28.8% vs. 9.5%, p < 0.001). The number of patients treated for malignant lesions was higher in the RT group (86.8% vs. 75%, p < 0.001). The rate of thyroiditis was higher in the RT group (10.9% vs. 6.6%, p < 0.001). Surgical time was significantly shorter in the RT group (140 vs. 165min, p < 0.001). Drainage volume was higher in the RT group (100 vs. 85ml, p < 0.001). Postoperative hospital stay was shorter in the RT group (3.04 ± 0.44 vs. 3.67 ± 0.89 days, p < 0.001). The cost in the RT group was higher (49627 ± 2795 vs. 25094 ± 3368 yuan, p < 0.001). Transient vocal cord dysfunction was lower in the RT group (2.9% vs. 8.0%, p = 0.003). There was no significant difference between the two groups in the number of central lymph nodes sampled, positive lymph nodes, neural monitoring (EMG) results, and rate of transient hypoparathyroidism. The learning curve for RT was 26 cases, and the operative time for ET was constant throughout the study.

CONCLUSIONS

RT-BABA is as safe and feasible as ET-BAA. RT-BABA performed better in some surgical outcomes. Further prospective studies are needed to confirm the safety of RT-BABA.

Factors in the occurrence and restoration of hypoparathyroidism after total thyroidectomy for thyroid cancer patients with intraoperative parathyroid autotransplantation

INTRODUCTION

Postoperative hypoparathyroidism (POH) is the most common and important complication for thyroid cancer patients who undergo total thyroidectomy. Intraoperative parathyroid autotransplantation has been demonstrated to be essential in maintaining functional parathyroid tissue, and it has clinical significance in identifying essential factors of serum parathyroid hormone (PTH) levels for patients with parathyroid autotransplantation. This retrospective cohort study aimed to comprehensively investigate influential factors in the occurrence and restoration of POH for patients who underwent total thyroidectomy with intraoperative parathyroid autotransplantation (TTIPA).

METHOD

This study was conducted in a tertiary referral hospital, with a total of 525 patients who underwent TTIPA. The postoperative serum PTH levels were collected after six months, and demographic characteristics, clinical features and associated operative information were analyzed.

RESULTS

A total of 66.48% (349/525) of patients who underwent TTIPA were diagnosed with POH. Multivariate logistic regression indicated that Hashimoto's thyroiditis (OR=1.93, 95% CI: 1.09-3.42), P=0.024), the number of transplanted parathyroid glands (OR=2.70, 95% CI: 1.91-3.83, P<0.001) and postoperative blood glucose levels (OR=1.36, 95% CI: 1.06-1.74, P=0.016) were risk factors for POH, and endoscopic surgery (OR=0.39, 95% CI: 0.22-0.68, P=0.001) was a protective factor for POH. Multivariate Cox regression indicated that PTG autotransplantation patients with same-side central lymph node dissection (CLND) (HR=0.50; 95% CI: 0.34-0.73, P<0.001) demonstrated a longer time for increases PTH, and female patients (HR=1.35, 95% CI: 1.00-1.81, P=0.047) were more prone to PTH increases. Additionally, PTG autotransplantation with same-side CLND (HR=0.56, 95% CI: 0.38-0.82, P=0.003) patients had a longer time to PTH restoration, and patients with endoscopic surgery (HR=1.54, 95% CI: 1.04-2.28, P=0.029) were more likely to recover within six months.

CONCLUSION

High postoperative fasting blood glucose levels, a large number of transplanted PTGs, open surgery and Hashimoto's thyroiditis are risk factors for postoperative POH in TTIPA patients. Elevated PTH levels occur earlier in female patients and patients without CLND on the transplant side. PTH returns to normal earlier in patients without CLND and endoscopic surgery on the transplant side.

PTH after Thyroidectomy as a Predictor of Post-Operative Hypocalcemia

Post-thyroidectomy hypocalcemia is a frequent complication with significant morbidity, and has been shown to increase hospital stay and readmission rates. The evaluation of serum parathyroid hormone (PTH) levels after thyroidectomy represents a reliable method to predict post-thyroidectomy hypocalcemia, but it remains infrequently used. This retrospective study investigates serum PTH values 3 h after thyroidectomy as a predictor of hypocalcemia. In this study, we enrolled 141 patients aged between 27 and 71 years eligible for total thyroidectomy who presented with multinodular goiter, suspicious nodule on cytological examination, Graves’ disease, or toxic multinodular goiter. Three hours after total thyroidectomy, 53 patients (37.6%) showed a reduction in serum PTH. Of these patients 75.5% developed hypocalcemia by 24 h after surgery and 100% were hypocalcemic after 48 h (p < 0.001). There was no significant difference attributable to the different thyroid diseases, nor to the age of the patients. PTH at 3 h after total thyroidectomy accurately predicts post-operative hypocalcemia. The early detection of patients at risk of developing post-operative hypocalcemia allows for prompt supplementation of calcium and Vitamin D in order to prevent symptoms and allows for a safe and timely discharge.