Preservation Of Parathyroid Glands Research Articles

Frequency and outcomes of parathyroid preservation in total thyroidectomy.

Objective: To determine the frequency and its outcome of parathyroid preservation in total thyroidectomy. Study Design: Case Series study. Setting: Department of Otorhinolaryngology, HMC, MTI, Peshawar. Period: 23rd June 2022 to 23rd Dec 2022. Methods: A total of 246 patients who underwent thyroidectomy were included in the study and followed up to determine the preservation of parathyroid gland, hypocalcaemia and recurrent laryngeal nerve injury. Results: The mean age of the sample was 37.7 + 12.3 years. There were 52.8% male patients and 47.2% female patients. 28.9% of patients had thyroid nodule and subtotal thyroidectomy was the most performed procedure Parathyroid gland preservation was recorded in 72%. On follow up, hypocalcemia was recorded in 16.3% and recurrent laryngeal nerve injury in 20.3%. Conclusion: Hypocalcemia and RLNI are significantly common after thyroidectomy. Hypocalcemia was significantly high in patients with low non preserved parathyroid gland. More research on high sample size and addressing other effect modifiers are recommended with intervention to preserve parathyroid gland.

Enhancing parathyroid preservation in papillary thyroid carcinoma surgery using nano-carbon suspension

This study evaluates the clinical significance of nano-carbon suspension in total thyroidectomy with cervical lymph node dissection for papillary thyroid carcinoma (PTC). The objective of this study was to assess the efficacy of nano-carbon suspension in enhancing parathyroid gland preservation, reducing postoperative complications, and improving surgical precision. A retrospective analysis on 219 PTC patients who underwent total thyroidectomy with cervical lymph node dissection between March 2014 and March 2018 was conducted. Patients were divided into two groups: an experimental group (n = 107) that received nano-carbon suspension and a control group (n = 112) that did not. Comparative analyses included demographics, surgical parameters, postoperative calcium and parathyroid hormone (PTH) levels, the number of dissected lymph nodes, and the incidence of complications. Baseline characteristics, including age, sex, and BMI, showed no statistically significant differences between the experimental and control groups. Postoperative calcium levels were significantly more stable in the experimental group, with median levels of 2.22 mmol/L on day 1 versus 2.06 mmol/L in the control group (P < 0.001), and 2.29 mmol/L at week 1 versus 2.22 mmol/L (P < 0.001). PTH levels were higher in the experimental group (35 pg/mL on day 1 versus 28 pg/mL, P < 0.001; 37 pg/mL at week 1 versus 30 pg/mL, P < 0.001). The experimental group had a greater median number of dissected lymph nodes (median 11.00 versus 7.00, P < 0.001) and a lower pathological parathyroid gland count (6.5% versus 23.2%, P < 0.001). Postoperative numbness and twitching were significantly reduced (4.7% versus 16.1%, P = 0.006), and the recurrence rate at 12 months was lower (4.7% versus 12.5%, P = 0.040). The use of Nano-carbon suspension in thyroidectomy and cervical lymph node dissection for PTC enhances parathyroid gland preservation, improves surgical precision, and reduces specific postoperative complications, supporting its standard adoption in thyroid cancer surgeries to optimize patient outcomes.

Risk Factors for Transient and Permanent Hypoparathyroidism Following Thyroidectomy: A Comprehensive Review.

Hypoparathyroidism is a common complication following thyroidectomy, resulting in significant disturbances in calcium homeostasis due to low parathyroid hormone (PTH) levels. This comprehensive review examines the risk factors associated with transient and permanent hypoparathyroidism post-thyroidectomy, emphasizing surgical, patient-related, and perioperative factors. Transient hypoparathyroidism, characterized by temporary hypocalcemia resolving within weeks to months, is often managed with short-term calcium and vitamin D supplementation. In contrast, permanent hypoparathyroidism persists beyond six months post-surgery, necessitating lifelong supplementation and potentially PTH replacement therapy. The review delves into the anatomy and physiology of the parathyroid glands, mechanisms leading to hypoparathyroidism, and incidence rates. Surgical factors such as the extent of thyroidectomy, surgeon expertise, and intraoperative parathyroid gland preservation are critical in determining the risk of hypoparathyroidism. Patient factors, including age, sex, pre-existing conditions, and perioperative management, influence outcomes. Diagnostic and monitoring strategies, along with management protocols for both transient and permanent hypoparathyroidism, are discussed. Prevention strategies, emerging research, future surgical techniques, and intraoperative monitoring directions are highlighted to improve clinical outcomes. This review aims to enhance understanding, inform surgical practices, and optimize postoperative care to minimize the incidence and impact of hypoparathyroidism in thyroidectomy patients.

The Identification and Preservation of Parathyroid Gland during Thyroidectomy Using Carbon Nanoparticles

Abstract Background During thyroidectomy, the parathyroid gland as well as the recurrent laryngeal nerve iatrogenic injuries are the most serious complications in goiter surgery. However, recurrent laryngeal nerve injury has been reduced to minimum as a result of meticulous surgical techniques and intraoperative nerve monitoring. Objective To determine the potential role of intraoperative CN injections for identification and preservation of parathyroid glands, thereby reducing the postoperative hypocalcaemia and whether CNs can really improve the extent of thyroidectomy and neck dissection and help identify metastatic lymph nodes. Patients and Methods We did a prospective cohort study with comparative between two groups of patients, one group established with the conventional technique of thyroidectomy while the other group established using CN injection to see which group with less post-operative hypocalcemia. A hundred patients with benign and malignant goiter disorders underwent thyroidectomy assigned into two groups: group 1 (control group) included 50 cases established with the conventional technique and group 2 (interventional group) included 50 cases operated upon with CN injection technique. Results The results showed that in group 2; 47 patients had normal Ca ++ level (94%) while 3 cases had low Ca ++ level (hypocalcemia) (6%). But in group 1; 37 patients had normal Ca ++ level (74%) while 13 cases had low Ca ++ level (hypocalcemia) (26%). The three patients in group 2 and the 13 patients in group 1 who developed hypocalcemia were managed with IV and oral supplementation of calcium and vitamin D and recovery occurred within a period of 1 week to 1 month. Conclusion CN injection technique is safe, effective, and technically feasible which helped us to keep parathyroid gland during thyroidectomy and that led us to reduce the percentage of incidence post- operative complications. Also, it helped us to identify the parathyroid gland during the surgery, the safety for thyroid surgery is based on the protection and visualization of the normal anatomy of parathyroid glands and their blood supplies according to the CNs injection technique, as verified in our research. Others see that the sooner the parathyroid glands are identified, the lower the surgeon’s level of stress. New studies with larger numbers of cases and also application of the technique by different surgeons are important to confirm the reliability and effectiveness of this technique.

Long-term kidney outcomes in patients with permanent hypoparathyroidism after total thyroidectomy for benign disease: A population-based study

BackgroundPermanent hypoparathyroidism is a significant complication after total thyroidectomy. This study aimed to evaluate the long-term impact of postoperative permanent hypoparathyroidism on kidney outcomes. MethodsData of patients undergoing total thyroidectomy from 1999 to 2014 were retrieved. The estimated glomerular filtration rate was determined from serum creatinine results. Permanent hypoparathyroidism was defined as requiring oral calcium and vitamin D supplements postoperatively for at least 6 months. The primary outcome was a sustained decline in the estimated glomerular filtration rate from baseline by ≥50%. Secondary outcomes were end-stage kidney disease (a composite of sustained estimated glomerular filtration rate <15 mL/min/1.73 m2, need for dialysis, and kidney transplantation) and rate of estimated glomerular filtration rate decline. Patients with and without permanent hypoparathyroidism were compared. Multivariable Cox regression analysis was performed to identify independent risk factors for sustained estimated glomerular filtration rate decline by ≥50%. ResultsIn total, 3,245 patients were eligible for analysis; 418 patients (12.9%) had permanent hypoparathyroidism. Upon median follow-up of 11.6 years, more patients with permanent hypoparathyroidism had a sustained decline in estimated glomerular filtration rate from baseline by ≥50% compared to those without (15.6% vs 6.9%, P < .001). Similar findings were obtained on Kaplan–Meier analysis (P < .001). Permanent hypoparathyroidism was an independent risk factor for sustained estimated glomerular filtration rate decline by ≥50% (adjusted hazard ratio 2.77, P < .001). Other risk factors included age, preoperative estimated glomerular filtration rate <60 mL/min/1.73m2, and diabetes mellitus. Patients with permanent hypoparathyroidism had a more rapid estimated glomerular filtration rate decline (–1.60 vs –0.70 mL/min/1.73 m2/year, difference –0.91 mL/min/1.73m2/year, P < .001). ConclusionPatients with postsurgical permanent hypoparathyroidism were at greater risk of renal impairment. Further research is warranted to improve the identification and preservation of parathyroid glands during thyroidectomy to minimize patient morbidity.

Impact of Indocyanine Green Angiography on Postoperative Parathyroid Function: A Propensity Score Matching Study.

Background: Thyroidectomy constitutes an important portion of endocrine surgery procedures and is associated with various complications such as bleeding, recurrent laryngeal nerve injury, and postoperative hypoparathyroidsm. Effective parathyroid preservation during thyroid surgery is crucial for patient well-being, with current strategies heavily reliant on surgeon experience. Among various methods, Indocyanine Green Angiography (ICGA) offers a promising method for intraoperative assessment of parathyroid gland perfusion. Methods: In a retrospective study, patients undergoing bilateral thyroidectomy from January 2021 to January 2023 were analyzed, excluding those with previous thyroidectomy, parathyroid disease, or chronic kidney disease. The study compared a control group (n = 175) with an ICGA group (n = 120), using propensity score matching for statistical analysis. Matched cohorts included 120 patients in each group. The primary outcome of this study was identified as temporary postoperative hypoparathyroidism, with secondary outcomes including the rate of parathyroid reimplantation and the incidence of permanent postoperative hypoparathyroidism. Results: The ICGA group showed significantly more parathyroid autotransplantations (p < 0.01). While not statistically significant, the control group had a higher incidence of temporary postoperative hypoparathyroidism (p < 0.09). Rates of hypocalcemia on postoperative day 1 and permanent hypocalcemia were similar. Subgroup analysis indicated more postoperative day 1 hypoparathyroidism in the control group during central neck dissections (p < 0.049). Conclusions: Intraoperative ICGA use correlated with higher parathyroid autotransplantation and suggested reduced postoperative hypoparathyroidism. Changes in fluorescence intensity following a second ICG injection may provide an objective method to assess parathyroid perfusion. Further large-scale studies are needed to fully understand ICGA's impact on parathyroid preservation.

Defining competencies in robotic thyroidectomy: development of a model assessing an expert operator's intraoperative performance skills and cognitive strategies.

The changing medical education environment emphasizes the need for time efficiency, increasing the demand for competency-based medical education to improve trainees' learning strategies. This study was performed to determine the competencies required for successful performance of robotic thyroidectomy (RT) and to determine the consensus of experts for performance of RT. Data were collected through 12 semi-structured interviews with RT experts and 11 field observations. Cognitive task analysis was performed to determine the competencies required for experts to perform RT. A modified Delphi methodology was used to determine how 20 experts rated the importance of each item of RT performance on a Likert 7-point scale. The criteria for the Delphi consensus were set at a Cronbach's α≥0.80 with two survey rounds. After 11 field observations and 12 semi-structured interviews, 89 items were identified within six modules. These items were grouped into sub-modules according to their theme. The modified Delphi survey, involving 21 experts, reached the consensus standard during the second round (Cronbach's α=0.954), enabling the identification of the 64 most important items within six modules related to RT performance: midline incision to isthmectomy (MID module; n=8), lateral dissection (LAT module; n=7), preservation of inferior parathyroid glands (INF module; n=16), preservation of recurrent laryngeal nerve and dissection of the ligament of Berry (BER module; n=21), dissection of the thyroid upper pole (SUP module; n=10), and specimen removal and closure (END module; n=2). This mixed-method study combining qualitative and quantitative methodology identified modules of core competencies required to perform RT. These modules can be used as a standard and objective guide to train surgeons to perform RT and evaluate outcomes.

Intraoperative AI-assisted early prediction of parathyroid and ischemia alert in endoscopic thyroid surgery.

The preservation of parathyroid glands is crucial in endoscopic thyroid surgery to prevent hypocalcemia and related complications. However, current methods for identifying and protecting these glands have limitations. We propose a novel technique that has the potential to improve the safety and efficacy of endoscopic thyroid surgery. Our study aims to develop a deep learning model called PTAIR 2.0 (Parathyroid gland Artificial Intelligence Recognition) to enhance parathyroid gland recognition during endoscopic thyroidectomy. We compare its performance against traditional surgeon-based identification methods. Parathyroid tissues were annotated in 32 428 images extracted from 838 endoscopic thyroidectomy videos, forming the internal training cohort. An external validation cohort comprised 54 full-length videos. Six candidate algorithms were evaluated to select the optimal one. We assessed the model's performance in terms of initial recognition time, identification duration, and recognition rate and compared it with the performance of surgeons. Utilizing the YOLOX algorithm, we developed PTAIR 2.0, which demonstrated superior performance with an AP50 score of 92.1%. The YOLOX algorithm achieved a frame rate of 25.14 Hz, meeting real-time requirements. In the internal training cohort, PTAIR 2.0 achieved AP50 values of 94.1%, 98.9%, and 92.1% for parathyroid gland early prediction, identification, and ischemia alert, respectively. Additionally, in the external validation cohort, PTAIR outperformed both junior and senior surgeons in identifying and tracking parathyroid glands (p < 0.001). The AI-driven PTAIR 2.0 model significantly outperforms both senior and junior surgeons in parathyroid gland identification and ischemia alert during endoscopic thyroid surgery, offering potential for enhanced surgical precision and patient outcomes.

Parathyroid gland preservation in laryngectomy patients with total thyroidectomy

BackgroundPostoperative hypocalcemia in laryngectomy patients can occur when part or whole of the thyroid gland has been removed. Preservation of the parathyroid glands in situ is considered one of the initial measures to prevent postoperative hypocalcemia even if all thyroid gland is removed. Our study aims to assess the efficacy of parathyroid gland preservation in situ to prevent postoperative hypocalcemia in cases where total laryngectomy is done with total thyroidectomy.MethodsThe study included all laryngectomy patients done during a period from April 2020 to May 2021. Parathyroid gland preservation was done in both primary (12 cases) and salvage (16 cases). Both PTH and corrected calcium level were measured at different time points and used as a guide for further replacement.ResultsWe studied the association between outcome including recovery from transient hypocalcemia and certain variables like age, type of surgery, stage of tumor, and extent of neck dissection. Regarding type of surgery, all patients that underwent primary laryngectomy were totally recovered (n = 12, 100%); however, salvage cases were partially recovered (n = 10, 62.5%).ConclusionParathyroid preservation is achievable in cases of salvage laryngectomy in addition to primary laryngectomy with total thyroidectomy. Early monitoring of the patients PTH and Ca during their hospital stay is a good indicator of successful preservation. Long-term follow-up is advised for potential recovery from transient hypoparathyroidism.

Intraoperative prevention of postoperative hypoparathyroidism.

More than 30,000 thyroid surgeries are performed annually in the Russian Federation. The surgeries are relatively safe because of the prevention methods for postoperative complications. Currently, there is no single effective method of postoperative hypoparathyroidism prevention. This complication is frequently reported and may be health and life-threatening. We aimed to estimate the effectiveness of the intraoperative ICG-angiography and intrathyroid injection of Brilliant Green for the prevention of postoperative hypoparathyroidism. One hundred and forty-three thyroidectomies were performed. Patients were divided into three groups: intraoperative angiography was used in 24 cases; Brilliant Green was injected in 58 cases to identify parathyroid glands; the visual estimation of the parathyroid preservation was used in 61 cases. Calcium level was measured in all patients before and after surgery. Calcium level in the serum before and after surgery was 2.37±0.14 and 2.27±0.17 in Group 1, 2.38±0.16 and 2.21±0.16 in Group 2, and 2.39±0.17 and 2.18±0.19 in Group 3. Postoperative hypocalcemia was more prominent in the group with the visually estimated PTG than in the two other groups. The differences in postoperative calcium levels in Groups 1 and 3 were statistically different. Pre- and postoperative Parathormone levels were 6.2±0.4 in Group 1, 5.6±0.57 in Group 2, and 3.5±0.32 in Group 3. Postoperative levels significantly differed in Groups 1 and 3 (p<0.01) and in Groups 2 and 3 (p<0.05). ICG-angiography and intrathyroid injection of the Brilliant Green are safe methods of identification and sparing of the parathyroid glands. The severity of hypocalcemia and hypoparathormonemia in Group 3 shows the necessity of finding new methods in endocrine surgery to improve patient outcomes.

Incidental parathyroidectomy during total thyroidectomy and functional parathyroid preservation: a retrospective cohort study

BackgroundThe published rate of incidental parathyroidectomy (IP) during thyroid surgery varies between 5.8% and 29%. The risk factors and clinical significance of postoperative transient hypocalcemia and permanent hypoparathyroidism are still debated. The aims of this study were to assess the clinical relevance of avoidable IP for transient hypocalcemia and permanent hypoparathyroidism, and to describe the risk factors for IP.MethodsThis retrospective cohort study included 1,537 patients who had a one-step total thyroidectomy in a high-volume endocrine surgery center between 2018 and 2019. Pathology reports were reviewed for incidentally removed parathyroid glands. Intrathyroidal parathyroid glands were excluded from the study. Demographic characteristics, potential risk factors, and postoperative calcium and PTH levels were compared between IP and control groups.ResultsAvoidable IP occurred in 234 (15.2%) patients. Patients with IP had a higher risk of transient hypocalcemia (17.9% vs. 11.5%, p = 0.006; odds ratio [OR] 1.68, 95% confidence interval [95% CI]1.16–2.45) and permanent hypoparathyroidism (4.7% vs. 1.6%, p = 0.002; OR 3.01, 95% CI 1.29–6.63) than patients without IP. Multivariate analysis showed that central lymph node dissection (CLND) and incidental removal of thymus tissue were independent risk factors for IP (OR 4.83, 95% CI 2.71–8.86, p < 0.001 and OR 1.72, 95% CI 1.02–2.82, p = 0.038).ConclusionsPatients with IP were more likely to develop transient hypocalcemia and permanent hypoparathyroidism, indicating the clinical significance of avoidable IP for patients and the need for raising awareness among surgeons. Patients undergoing CLND are at a higher risk for IP, and should be adequately informed and treated. Any removal of thymus tissue should be avoided during CLND.

Methods for the identification and preservation of parathyroid glands in thyroid surgery: a narrative review.

Accurate intraoperative identification and viability assessment of the parathyroid glands (PGs) has always been a crucial but challenging aspect of thyroid surgery. The traditional method, naked-eye (NE) assessment, is significantly associated with the experience of the surgeon. Therefore, various methods have been developed to help surgeons protect PGs, with some benefits and limitations. Recently, near-infrared autofluorescence (NIRAF) and indocyanine green fluorescence imaging (ICGFI) have been demonstrated to be promising in the identification and viability assessment of PGs. Herein, we provide an overview of the methods of intraoperative identification and viability assessment of PGs, focusing on the application of NIRAF and ICGFI. We performed a systematic literature search of PubMed, Medline, Cochrane Library databases, Web of Science, and EMBASE to identify all relevant studies published up to March 2023. The keywords were ((autofluorescence) OR (indocyanine green)) AND (parathyroid gland). In this narrative review, we summarized the benefits and limitations of intraoperative methods for PG identification and viability assessment, focusing on the application of NIRAF and ICGFI. Intraoperative parathyroid protection methods have developed from traditional subjective identification of PGs to the latest near-infrared (NIR) fluorescence imaging technology. The discovery, development, and application of NIRAF and ICGFI have provided better ways for surgeons to protect PGs intraoperatively.

Evaluation of Early &amp; Late Hypocalcemia Post Total Thyroidectomy in the Early Learning Curve Retrospective Study

Abstract Background Hypocalcemia post total thyroidectomy, is one of the most common complications observed in patients who undergo bilateral thyroid resection. Although hypocalcemia is self-limiting in most patients and does not require treatment, symptomatic hypocalcemia is of particular concern. We aimed to evaluate the incidence of hypocalcemia post total thyroidectomy with an evaluation of serum calcium levels as a cheap and available method so we can identify patients at risk of postoperative hypocalcemia who require supplementation treatment, and those not at risk who can be safely discharged without any supplementation treatment. Aim of the Work To analyze the data of post total thyroidectomy regarding calcium level temporary and permanent in the early learning curve and compare it with the standard incidence of developing hypocalcemia with total thyroidectomy in the literature. Patients and Methods Retrospective analysis of 120 patients undergoing total thyroidectomy. Preservation of parathyroid glands and their blood supply was attempted in all cases. The patients were assessed for manifestations of hypocalcaemia after thyroidectomy. The assessment was done through (1) monitoring the total and ionized calcium level 24 hours postoperatively, (2) Total and ionized calcium level was measured in the third week postoperative, (3) clinical examination and detection of symptoms and signs of hypocalcaemia, (4) In resistant cases assessment of total and ionized calcium and PTH at 3 and 6 months. Results The study included 103 females and 17 males, 37 was the mean age; 15 patients developed symptoms of hypocalcaemia all of them recovered from hypocalcaemia except 1 patient. Conclusion There is no difference between the incidence of temporary and permanent hypocalcemia in the early learning curve and the standard incidence of temporary and permanent hypocalcemia post total thyroidectomy

The role of autofluorescence and Indocyanine green (ICG) in Endocrine Surgery

Parathyroid preservation during total thyroidectomy is crucial in preventing postoperative hypoparathyroidism. The use of intraoperative parathyroid hormone monitoring has been shown to reduce the incidence of hypoparathyroidism. However, this method has limitations, and alternative techniques such as autofluorescence and ICG angiography have emerged as potential options for parathyroid preservation. The use of ICG angiography and near-infrared autofluorescence has shown promise in improving parathyroid gland preservation and reducing the risk of postoperative hypocalcaemia and hypoparathyroidism. The combination of autofluorescence and ICG angiography has also been found to be useful in identifying parathyroid glands in challenging cases, such as reoperations for thyroid or parathyroid diseases. However, further studies are needed to establish its long-term safety and efficacy and to address the limitations of its implementation in clinical practice.

Parathyroid preservation in total endoscopic thyroid surgeries via the mammary areolas approach: Real-world data from a single center

BackgroundPreserving parathyroid glands in situ is crucial to avoid surgical hypoparathyroidism, but it is also one of the greatest challenges during thyroid surgery. Magnified endoscopic imaging has been proposed as a way to improve parathyroid preservation. Methods2,603 consecutive patients who underwent thyroid surgery at the First People’s Hospital of Zunyi from January 2018 to July 2022 were screened. 1,355 patients were eligible, including 965 endoscopic and 390 open cases. Parathyroid hormone (PTH) loss levels and severe parathyroid injury rates were compared between endoscopic and open cases. Meanwhile, factors that contribute to parathyroid injuries were assessed, including surgical extent, tumor size, carbon nanoparticle guidance, and surgical proficiency. ResultsPTH loss levels were similar between endoscopic and open cases (P = 0.440). The incidence of severe parathyroid injuries was also comparable (7.8% for endoscopic vs. 6.9% for open, P = 0.592). The endoscopic group had higher rates of autologous parathyroid transplantation (39.5% vs. 24.4%, P = 0.000), while accidental parathyroidectomy rates were similar (11.4% vs. 10.8%, P = 0.739). Among patients who received the same extent of thyroid surgeries, no significant difference was found in PTH loss levels and severe parathyroid injury rates, except for a higher risk of severe parathyroid injuries in endoscopic bilateral thyroidectomy (18.52% vs. 11.52%, P = 0.033). ConclusionsDespite the magnified endoscopic imaging facilitating the identification of parathyroid tissues, endoscopic approaches are not superior to open ones for the in-situ preservation of parathyroid glands. For a bilateral thyroidectomy, open approaches are safer for parathyroid preservation.

Preservation of parathyroid glands during thyroid and neck surgery.

The parathyroid glands are situated in close proximity to the thyroid gland. They have an important endocrine function maintaining calcium and phosphate homeostasis in the body by the secretion of parathormone (PTH), which is responsible for this function. The parathyroid glands are commonly damaged during thyroid surgeries. This could lead to transient or permanent hypoparathyroidism in 30% of cases. Preservation of the parathyroid glands, is an important and integral part of thyroidectomy and other surgical interventions in the neck. The main principle underlying this is a thorough understanding of parathyroid anatomy in relation to the thyroid gland and other important structures in the area. There can also be significant variation in the anatomical location of the glands. Various techniques and methods have been described for parathyroid preservation. They include intraoperative identification utilizing indocyanine green (ICG) fluorescence, carbon nanoparticles, loupes, and microscopes. The techniques of surgery (meticulous capsular dissection), expertise, central compartment neck dissection, preoperative vitamin D deficiency, extent and type of thyroidectomy are the risk factors associated with damaged thyroids, inadvertent parathyroidectomy and subsequent hypoparathyroidism. Parathyroid Autotransplantation is a treatment option for inadvertent parathyroidectomy. Ultimately, the best way to assure normal parathyroid function is to preserve them in situ intraoperatively undamaged.

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

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

A review of parathyroid autofluorescence imaging in detection and preservation of parathyroid glands during thyroid surgery

: The increasing number of thyroid cancers has prompted a subsequent increase in thyroidectomies. Although it is considered a safe operation it is still prone to complications. Hypocalcemia has been cited as the most common complication after thyroidectomy. Although this event is temporary in the majority of the cases, in a not insignificant number of cases it can be permanent. Hypocalcemia, can heavily impact the patient’s quality of life. The mechanism responsible for hypocalcemia after thyroidectomy is a disruption of the parathyroid glands (PGs) and its vascular supply. Therefore, it is key to identify the PGs during thyroidectomy to make it a safe operation. Traditionally, the identification has relied on visual inspection which is largely dependent on the surgeon’s experience. Different technological aids have been used throughout the years to help the surgeon identify the PGs. In the last decade, it was found that the PGs exhibit autofluorescence (AF) when stimulated with near-infrared (NIR) light at 785 nm [near-infrared autofluorescence (NIRAF)]. This technology can aid the surgeon in the intraoperative identification of parathyroid tissue and hence avoid postoperative hypocalcemia. As surgeons using a new technology have to be well versed in the concepts behind it, this review will describe the landmark studies which led to the development of parathyroid AF and its application in thyroidectomy.

Intraoperative Autofluorescence Imaging for Parathyroid Gland Identification during Total Laryngectomy with Thyroidectomy.

Hypoparathyroidism is a known complication of total laryngectomy, although parathyroid preservation and/or reimplantation are not routine. Autofluorescence is a new technique for identifying parathyroid glands intraoperatively. The aim of this study was to evaluate the feasibility of autofluorescence in this context. A retrospective study of patients undergoing total laryngectomy/pharyngectomy with concomitant thyroidectomy using the Fluobeam® (Fluoptics, Grenoble, France) and frozen section of a parathyroid fragment in case of reimplantation. The rates of identification using autofluorescence, reimplantation, and hypoparathyroidism were evaluated. Eighteen patients (16 males, median age 67) underwent total laryngectomy/pharyngectomy with total thyroidectomy (n = 12) or hemithyroidectomy (n = 6). A median of 2 parathyroid glands were identified per patient. Ninety-two percent were identified by autofluorescence before visualisation. All parathyroids were reimplanted due to devascularization. Temporary hypoparathyroidism occurred in nine patients, and was permanent in one patient. After 34 months of median follow-up (range 1-49), no tumor recurrence was observed in the reimplantation sites. To our knowledge, this is the largest study to evaluate autofluorescence during total laryngectomy with thyroidectomy. No tumor recurrence occurred in the sites of parathyroid reimplantation.

Indocyanine green fluorescence angiography in transoral endoscopic thyroidectomy for papillary thyroid cancer

To evaluate the effectiveness of ICG angiography in patients with papillary thyroid cancer (PTC) undergoing transoral endoscopic thyroidectomy (TOETVA) and selective neck dissection (level VI). A retrospective analysis included 20 patients with PTC who underwent TOETVA with selective neck dissection (level VI) between September and December 2022. ICG was administered intravenously (5 mg ´ 3 times). We analyzed parathyroid glands by visual examination and ICG angiography. Fluorescence of all glands was assessed. Twenty patients underwent ICG angiography during TOETVA. A total of 68 parathyroid glands were identified. Only 76.5% (52/68) of parathyroid glands were identified at initial visual examination. ICG angiography additionally localized 12 glands that improved detection to 94.1% (64/68). At least one well-vascularized parathyroid gland was demonstrated by ICG angiography in 16 patients. In all these patients, serum parathyroid hormone was normal in 1 and 10 days after surgery. Two out of four patients who failed to identify a well-vascularized parathyroid gland developed transient hypoparathyroidism. There were no intraoperative and postoperative complications associated with ICG angiography. ICG angiography was simple, safe and effective for better identification and preservation of parathyroid glands in patients with PTC undergoing TOETVA. This method was valuable for assessing the viability and function of parathyroid glands and predicting postoperative hypocalcemia.