Intraoperative Identification Of Parathyroid Glands Research Articles

Intraoperative detection of parathyroid glands using artificial intelligence: optimizing medical image training with data augmentation methods

BackgroundPostoperative hypoparathyroidism is a major complication of thyroidectomy, occurring when the parathyroid glands are inadvertently damaged during surgery. Although intraoperative images are rarely used to train artificial intelligence (AI) because of its complex nature, AI may be trained to intraoperatively detect parathyroid glands using various augmentation methods. The purpose of this study was to train an effective AI model to detect parathyroid glands during thyroidectomy.MethodsVideo clips of the parathyroid gland were collected during thyroid lobectomy procedures. Confirmed parathyroid images were used to train three types of datasets according to augmentation status: baseline, geometric transformation, and generative adversarial network-based image inpainting. The primary outcome was the average precision of the performance of AI in detecting parathyroid glands.Results152 Fine-needle aspiration-confirmed parathyroid gland images were acquired from 150 patients who underwent unilateral lobectomy. The average precision of the AI model in detecting parathyroid glands based on baseline data was 77%. This performance was enhanced by applying both geometric transformation and image inpainting augmentation methods, with the geometric transformation data augmentation dataset showing a higher average precision (79%) than the image inpainting model (78.6%). When this model was subjected to external validation using a completely different thyroidectomy approach, the image inpainting method was more effective (46%) than both the geometric transformation (37%) and baseline (33%) methods.ConclusionThis AI model was found to be an effective and generalizable tool in the intraoperative identification of parathyroid glands during thyroidectomy, especially when aided by appropriate augmentation methods. Additional studies comparing model performance and surgeon identification, however, are needed to assess the true clinical relevance of this AI model.Graphical abstract

Evaluating the effectiveness of dual dye combination of indocyanine green and carbon nanoparticles with parathyroid hormone test in preserving parathyroid gland during papillary thyroid cancer surgery: a single-center retrospective cohort study.

Preserving the integrity of parathyroid glands is crucial in papillary thyroid cancer (PTC) surgery to avoid hypoparathyroidism. In recent years, two novel dyes, activated carbon nanoparticles (CNP) and indocyanine green (ICG), have been utilized to assist in parathyroid gland identification. However, the use of CNP or ICG alone can result in extravasation of dye or excessive fluorescence of non-parathyroid tissue, which can affect the accuracy of surgical outcomes by yielding false negative or false positive results. Therefore, it is important to further optimize the application of these two dyes in surgery. We analyzed case files of 124 PTC patients who underwent routine total or near-total thyroidectomy with bilateral lymph node dissection in the central region at the Affiliated People's Hospital of Ningbo University from January to November 2022. The patients were randomly divided into three groups based on the type of intraoperative dye used. The CNP group (n = 38) received an intra-thyroidal injection of CNP dye. The ICG group (n = 42) used the ICG near-infrared fluorescence endoscopy system to show parathyroid fluorescence. The group that received a combined approach of ICG and CNP (n = 44) leveraged the advantages of both methods that allow for positive development of ICG and negative development of CNP to identify and preserve the parathyroid gland during operation. The parathyroid hormone detection reagent (PTH test method) was employed to verify the highly suspected parathyroid tissue in all three groups. We analyzed intraoperative data pertaining to intraoperative parathyroid identification, misexcision, number of autotransplantation, and postoperative hypoparathyroidism among the three groups. Compared with the ICG group and the CNP group, the combined group demonstrated more prominent advantages in identifying average the number of lower parathyroid glands (1.93 ± 0.26, p = 0.015), reducing the average numberrate of misexcision (0.45 ± 0.5, p = 0.004), and reducing the incidence of postoperative temporary hypothyroidism (3/44, p = 0.015). The combined use of ICG and CNP dual-dye with PTH test method appears to be more effective in both identifying and protecting parathyroid glands during PTC surgery.

Improvement in Central Neck Dissection Quality in Thyroid Cancer by Use of Tissue Autofluorescence.

Risk of postoperative transient or permanent hypoparathyroidism represents one of the most common complications following total thyroidectomy. This risk increases if a cervical lymphadenectomy procedure must also be performed, as is usually the case in thyroid carcinoma patients. Parathyroid autofluorescence (AF) is a non-invasive method that aids intraoperative identification of parathyroid glands. In this prospective study, 189 patients with papillary thyroid cancer who underwent total thyroidectomy with central neck dissection were included. Patients were randomly allocated to one of two groups: NAF (no AF, surgery was performed without AF) and the AF group (surgery was performed with AF-Fluobeam LX system, Fluoptics, Grenoble, France). The number of excised lymph nodes was significantly higher in the AF compared to the NAF group, with mean values of 21.3 ± 4.8 and 9.2 ± 4.1, respectively. Furthermore, a significantly higher number of metastatic lymph nodes were observed in the AF group. Transient hypocalcemia recorded significantly lower rates in the AF group with 4.9% compared to 16.8% in the NAF group. AF use during total thyroidectomy with central neck dissection for papillary thyroid carcinoma patients, decreased the rate of iatrogenic parathyroid gland lesions, and increased the rate of lymphatic clearance.

Heterogeneous parathyroid near-infrared autofluorescence patterns are associated with single adenomas in primary hyperparathyroidism.

Primary adenoma (PA) and multi-gland hyperplasia (MGH) account for 85% and 15% of primary hyperparathyroidism (PHPT) cases, respectively. Near-infrared autofluorescence (NIRAF) enhances intraoperative parathyroid identification. We hypothesized that PA would display a more heterogeneous NIRAF pattern compared to MGH. Patients undergoing surgery for sporadic PHPT were categorized based on the presence of PA or MGH. To quantify heterogeneity, we utilized ratios of (1) mean parathyroid gland (PG) NIRAF over background NIRAF (mean ratio), (2) minimum and (3) maximum PG NIRAF over mean PG NIRAF (minimum and maximum ratios). Additionally, a heterogeneity score was quantified using mean ratio (mean PG NIRAF over background NIRAF), and overall NIRAF (mean NIRAF of eight random 15 × 15 pixel areas). A point was assigned to ratios <0.8 or >1.2. Images were quantified by ImageJ software. Mann-Whitney test was performed for all comparisons. Of 78 patients, 63 had a single PA and 15 had MGH, totaling 102 PGs. There was no difference between their mean ratios. PA had a lower minimum ratio compared to that of MGH (0.86 ± 0.01 vs. 0.93 ± 0.01, p = 0.001) and a brighter maximum ratio (1.21 ± 0.02 vs. 1.12 ± 0.01, p = 0.0008). PA also scored higher on their heterogeneity scores compared to MGH (1.27 ± 0.23 vs. 0.33 ± 0.15, p = 0.001). Single parathyroid adenomas display a more heterogeneous autofluorescence pattern compared to that of multi-gland hyperplasia. Intraoperative characterization of PGs by real-time NIR imaging patterns may be a beneficial adjunct during parathyroid surgery.

420 Parathyroid surgery outcomes - 2 surgeons outcomes for the past 9 years in a teaching hospital

Abstract Aim The success of parathyroid surgery in hyperparathyroidism is defined by the sustained improvement in calcium levels without the need for re-exploration. Reoperation rate in the United Kingdom currently sits at 1.6%. It has been shown that the need for repeat parathyroid surgery is related to surgeon annual volume. We aimed to review the outcomes of parathyroid surgery for hyperparathyroidism performed by two upper gastrointestinal surgeons experienced in parathyroidectomies. Methods Retrospective review of consecutive parathyroidectomy cases performed by VS and PT in a teaching hospital was conducted between April 2013 and December 2022. Data was obtained from local hospital database. Primary outcome was re-exploration within one year of index procedure. Secondary outcomes included methylene blue uptake by adenomas and postoperative vocal cord palsy. Results 211 parathyroidectomies were performed during the study period. Patient cohort was predominantly female (n=153, 72.2%). Mean age of study population was 57±13 years. Histopathology confirmed 171 (81.0%) parathyroid adenomas, 34 (16.1%) multiglandular hyperplasia and 6 (2.8%) normal glandular tissue. None were malignant adenoma. 4 (1.9%) patients required re-exploration within one year of index procedure, three of which were found to be ectopic adenomas. Preoperative methylene blue infusion was used in all cases to assist identification of adenoma; uptake was evident in 169 (80.1%) cases. 2 (0.9%) patients developed permanent recurrent laryngeal nerve damage, resulting in mild voice hoarseness. Conclusion Our dedicated parathyroid service led by experienced surgeons was associated with comparable re-exploration rates and high cure rates. Preoperative methylene blue infusion helps in intraoperative identification of parathyroid glands.

Magic Pen?—An Innovative Adjunct for Intraoperative Identification of Parathyroid Glands

Magic Pen?—An Innovative Adjunct for Intraoperative Identification of Parathyroid Glands

Identifying Parathyroids in Pediatric Thyroid/Parathyroid Surgery by Near Infrared Autofluorescence.

Compared to adult patients undergoing thyroid surgery, pediatric patients have higher rates of hypoparathyroidism often related to parathyroid gland (PG) inadvertent injury or devascularization. Previous studies have shown that near-infrared-autofluorescence (NIRAF) can be reliably used intraoperatively for label-free parathyroid identification, but all prior studies have been performed in adult patients. In this study, we assess the utility and accuracy of NIRAF with a fiber-optic probe-based system to identify PGs in pediatric patients undergoing thyroidectomy or parathyroidectomy. All pediatric patients (under 18 years of age) undergoing thyroidectomy or parathyroidectomy were enrolled in this IRB-approved study. The surgeon's visual assessment of tissues was first noted and the surgeon's confidence level in the tissue identified was recorded. A fiber-optic probe was then used to illuminate tissues-of-interest with a wavelength of 785 nm and resulting NIRAF intensities from these tissues were measured while the surgeon was blinded to results. NIRAF intensities were measured intraoperatively in 19 pediatric patients. Normalized NIRAF intensities for PGs (3.63 ± 2.47) were significantly higher than that of thyroid (0.99 ± 0.36, p < 0.001) and other surrounding soft tissues (0.86 ± 0.40, p < 0.001). Based on the PG identification ratio threshold of 1.2, NIRAF yielded a detection rate of 95.8% (46/48 pediatric PGs). Our findings indicate that NIRAF detection can potentially be a valuable and non-invasive technique to identify PGs during neck operations in the pediatric population. To our knowledge, this is the first study in children to assess the accuracy of probe-based NIRAF detection for intraoperative parathyroid identification. Level 4 Laryngoscope, 133:3208-3215, 2023.

Parathyroid Autofluorescence in Pediatric Thyroid Surgery: Experience With False Positive and False Negative Results.

Devices for near-infrared light stimulation of autofluorescence (NIRAF) allow for intraoperative identification of parathyroid glands with high sensitivity in adults. However, their performance in the pediatric population is unknown. In this case series with chart review at a tertiary academic children's hospital, we investigated pediatric patients undergoing thyroid surgery and concurrent use of a probe-based NIRAF device. Thirteen patients (ages 6-18 years) underwent thyroid and/or neck dissection procedures, and 2 patients had revision procedures for a total of 15 cases with the NIRAF device. Eight cases had NIRAF values that matched surgeon opinion of parathyroid tissue or histology when available. Six cases had false positive NIRAF readings (40.0%) and 1 case had false negative readings (6.7%). Compared with surgeon opinion or histology, the NIRAF device confirmed 26 of 34 parathyroid gland candidates (76.5%). These devices need further investigation in pediatric patients, whose tissues may have different autofluorescence characteristics.

On indocyanine green fluorescence and autofluorescence in thyroid and parathyroid surgery: A scoping systematic review

• We acknowledge the feasibility of using ICG and AF as a powerful tool for the identification of PG more effectively than with classic methods or the naked eye • These results are encouraging towards the use of such techniques intraoperatively • Further research is needed to obtain high-quality evidence showing a possible reduction in postoperative hypocalcaemia rates and clinical symptoms that would justify the use of these techniques in routine surgical practice. Autofluorescence (AF) and Indocyanine Green Fluorescence (ICG) were used for the first time for parathyroid gland identification in 2011 and 2015, respectively, during thyroidectomy and parathyroidectomy. Authors reported promising results. We aim to understand the impact on postoperative biochemical and clinical outcomes of these new techniques, as well as their influence on the intraoperative identification of parathyroid glands, the related technical challenges and their cost-effectiveness. A systematic search of PubMed/MEDLINE was performed with the help of MeSH and following the PRISMA guidelines. Overall, 58 studies were included dating from 2008 to August 2020 in English, German, Spanish, and French. Due to the mainly observational nature of the papers on the topic, letters to the editor and responses to previous papers were included. Papers combining the use of both techniques in the same cohort were included. We analysed a total of 3 RCTs, 33 observational studies, and 22 case series or reports. The use of AF/ICG increased the surgeon's confidence and demonstrated a better sensitivity for parathyroid gland identification in both thyroidectomies and parathyroidectomies compared to other techniques. Adverse events were uncommon. After reviewing the literature, we acknowledge the feasibility of using ICG and AF as a powerful tool for the identification of parathyroid glands more effectively than with classic methods or the naked eye. These results are encouraging towards the use of such techniques intraoperatively. However, further research is needed to obtain high-quality evidence showing a possible reduction in postoperative hypocalcaemia rates and clinical symptoms that would justify the use of these techniques in routine surgical practice.

Can Parathyroid Autofluorescence Distinguish Between Parathyroid Adenomas and Multigland Hyperplasia?

INTRODUCTION: Primary adenoma (PA) and multigland hyperplasia (MGH) account for 85% and 15% of primary hyperparathyroidism (pHPT) cases, respectively. Near-infrared autofluorescence (NIRAF) enhances intraoperative parathyroid identification. We hypothesized that PA would display a more heterogeneous NIRAF pattern than MGH. METHODS: Patients undergoing surgery for sporadic pHPT were categorized based on the presence of PA or MGH. To quantify heterogeneity, we used ratios of mean parathyroid gland (PG) NIRAF over background NIRAF (mean ratio), minimum and maximum PG NIRAF over mean PG NIRAF (minimum and maximum ratios). Additionally, a heterogeneity score was quantified using the mean ratio (mean PG NIRAF over background NIRAF), and overall NIRAF (mean NIRAF of 8 random 15×15 pixel areas). A point was assigned to ratios <0.8 or >1.2. Images were quantified by ImageJ software. Mann-Whitney test was performed for all comparisons. RESULTS: Of 78 patients, 63 had a single PA and 15 had MGH, totaling 102 PGs. There was no difference between their mean ratios. PA had a lower minimum ratio than that of MGH (0.86 ± 0.01 vs 0.93 ± 0.01, p = 0.001) and a brighter maximum ratio (1.21 ± 0.02 vs 1.12 ± 0.01, p = 0.0008). PA also scored higher on their heterogeneity scores than MGH (1.27 ± 0.23 vs 0.33 ± 0.15, p = 0.001). In sum, PA displayed a more heterogeneous pattern with significantly brighter and darker areas (Figure).FigureCONCLUSION: Single parathyroid adenomas display a more heterogeneous autofluorescence pattern compared with that of MGH. Intraoperative characterization of PGs by real-time near-infrared imaging patterns may be a beneficial adjunct during parathyroid surgery.

Intraoperative identification of parathyroid glands during endocrine surgery

Nowadays, diabetes and diseases of thyroid gland take place on the first two stage in the rank of all endocrine diseases. There are 3 directions to treat thyroid glands pathologies such as: using special pills which substitute natural thyroid hormones, surgery and radioiodine therapy. It has proven that surgery of thyroid gland is the most effective method among considering upper. at The same time, it is associated with the greatest risks of complications. The most common injuries are damage to the recurrent laryngeal nerve and unintentional traumatization or removal of a healthy parathyroid gland. Parathyroid gland is a critical organ during thyroid surgery. It means that all negative reaction nearby the structure can lead to development different complications: hypoparathyroidism (transient or chronic) and hypocalcemia. In this article is considered actual methods of intraoperative optical visualization of parathyroid glans. The fundamental foundations of such methods, their advantages and disadvantages are also analyzed. It is shown that fluorescent methods in the red and near infrared regions of the spectrum using exogenous dyes have essential importance for endocrine surgery, as they allow to improve identification and reduce the risk of postoperative complications.

Adrenal Near-Infrared Autofluorescence.

ContextParathyroid tissue is one of the few tissues to have strong near-infrared (NIR) autofluorescence, which has been exploited to improve intraoperative parathyroid identification. The US Food and Drug Administration has approved 2 devices for this purpose. Adrenal glands can be difficult to distinguish from surrounding fat, an issue during total adrenalectomy.ObjectiveWe hypothesized adrenal tissue may also possess considerable NIR autofluorescence.MethodsResected patient adrenal specimens were examined after robotic adrenalectomy with an NIR camera intraoperatively. Patients did not receive fluorescent dye. Images were taken of both gross and sectioned specimens. Post hoc image analysis was performed with ImageJ software. Confocal microscopy was performed on selected tissues using immunofluorescence and hematoxylin-eosin staining.ResultsResected tissue was examined from 22 patients undergoing surgery for pheochromocytomas (6), primary aldosteronism (3), adrenocorticotropin-independent hypercortisolism (10), and a growing or suspicious mass (3). Normal adrenal tissue demonstrated strong NIR autofluorescence. The intensity ratio compared to background (set as 1) for gross images was 2.03 ± 0.51 (P < .0001) compared to adjacent adipose of 1.24 ± 0.18. Autofluorescence from adrenal tumors was also detected at variable levels of intensity. Cortisol-producing tumors had the highest fluorescence ratio of 3.01 ± 0.41. Confocal imaging localized autofluorescence to the cytosol, with the highest intensity in the zona reticularis followed by the zona fasciculata.ConclusionNormal and abnormal adrenal tissues possess natural NIR autofluorescence. Highest autofluorescence levels were associated with cortisol-producing tumors. Confocal imaging demonstrated the highest intensity in the zona reticularis. NIR cameras may have the potential to improve identification of adrenal tissue during surgery.

Update on the Diagnosis and Management of Medullary Thyroid Cancer: What Has Changed in Recent Years?

Simple SummaryMedullary thyroid carcinoma (MTC) is a rare neoplasm that is responsible for a fair proportion of thyroid carcinoma related deaths. The current diagnostic and therapeutic standards are not always effective and need to be upgraded. The role of biomarkers and immunohistochemistry in the diagnosis of MTC is highlighted. Opportunities for improved diagnostics have been seen with the development of nuclear medicine. Some studies have highlighted the possibility of reducing the number of complications during surgical treatment, which is the basic therapeutic method in patients with MTC. Current pharmacotherapy is imperfect, but there is ongoing research into the use of new, more selective drugs. The following paper discusses recent advances in the diagnosis and treatment of MTC.Medullary thyroid carcinoma (MTC) is a neoplasm originating from parafollicular C cells. MTC is a rare disease, but its prognosis is less favorable than that of well-differentiated thyroid cancers. To improve the prognosis of patients with MTC, early diagnosis and prompt therapeutic management are crucial. In the following paper, recent advances in laboratory and imaging diagnostics and also pharmacological and surgical therapies of MTC are discussed. Currently, a thriving direction of development for laboratory diagnostics is immunohistochemistry. The primary imaging modality in the diagnosis of MTC is the ultrasound, but opportunities for development are seen primarily in nuclear medicine techniques. Surgical management is the primary method of treating MTCs. There are numerous publications concerning the stratification of particular lymph node compartments for removal. With the introduction of more effective methods of intraoperative parathyroid identification, the complication rate of surgical treatment may be reduced. The currently used pharmacotherapy is characterized by high toxicity. Moreover, the main limitation of current pharmacotherapy is the development of drug resistance. Currently, there is ongoing research on the use of tyrosine kinase inhibitors (TKIs), highly specific RET inhibitors, radiotherapy and immunotherapy. These new therapies may improve the prognosis of patients with MTCs.

Optical Tools for Intraoperative Parathyroid Identification

Optical Tools for Intraoperative Parathyroid Identification

Thyroidectomy with and without laryngectomy: Differences in post-operative hypocalcemia and management

BackgroundTotal laryngectomy (TL) with thyroidectomy can pose significant risks to parathyroid function, and variance in rates of post-operative hypocalcemia (POH) based on extent of thyroidectomy have not been previously reported. Our objective is to identify the rates of hypocalcemia and hypoparathyroidism in TL+/−thyroidectomy and compare this to matched thyroidectomy alone cohorts. MethodsMulti-institutional retrospective chart review of patients treated surgically for laryngeal cancer with TL or benign/malignant thyroid disease with thyroidectomy at regional tertiary care centers in New Orleans and Baton Rouge, Louisiana from 2016 to 2019. Cases were evaluated for post-operative and post-discharge calcium and parathyroid hormone levels, post-operative and long-term calcium supplementation, and intraoperative parathyroid identification and management. Results101 TL and 319 thyroidectomy patients' charts were reviewed. Regression analysis revealed increased odds of hypocalcemia and hypoparathyroidism in TL + TT versus TT alone (OR 10.7, OR 16.5, p < 0.001, respectively). TL + HT versus HT alone had increased odds of hypoparathyroidism (OR 1.6, p < 0.001). TL with any thyroidectomy compared to TL alone demonstrated both increased odds of hypocalcemia and hypoparathyroidism (OR 4.4 p = 0.009, and OR 4.5 p = 0.05). Odds of requiring long-term calcium supplementation were significantly increased with the addition of thyroidectomy across all groups. TL + TT was 8 times as likely (p = 0.002) and TL + HT was 5.3 times as likely (p = 0.001) to require long-term calcium supplementation compared to TL alone. ConclusionsThyroidectomy combined with TL demonstrates marked increased risk of parathyroid dysfunction and resultant POH. Despite improved visualization of soft tissue anatomy with TL, risk of parathyroid injury in these settings requires special attention to extent of parathyroid dissection and potential devascularization to reduce long-term sequelae of hyperparathyroidism. Therefore, post-operative calcium monitoring after TL is necessary and should resemble the long-standing stringent protocols that already exist for monitoring in thyroidectomy populations.

Evaluation of structural and ultrastructural changes in thyroid and parathyroid glands after near infrared irradiation: study on an animal model.

Intraoperative identification of parathyroid glands is a tough task for surgeons performing thyroid or parathyroid surgery, because the small size, color and shape of these glands hinder their discrimination from other cervical tissues. In 2011, Paras described the autofluorescence of parathyroid glands, a property that could facilitate their intraoperative identification. Parathyroid glands submitted to a 785 nm laser beam emit fluorescence in the near infrared range, with a peak at 822 nm. As the intrinsic properties of secretory tissues may be affected by the exposure to the near infrared light, a situation that could preclude their intraoperative utilization, the authors compared the structural and ultra-structural patterns of rat’s thyroid and parathyroid glands submitted to irradiation replicating the conditions that allow their intraoperative identification, with those of non irradiated animals. Twenty-four Wistar rats were divided into six groups: animals of Groups 1, 3 and 5 were submitted under general anesthesia to direct irradiation of the cervical area with a 780 nm LED light for 3 minutes through a cervical incision, and animals of Groups 2, 4 and 6 were submitted to cervical dissection without irradiation. Animals of were euthanized immediately (Groups 1 and 2), at Day 30 (Groups 3 and 4) at and at Day 60 (Groups 5 and 6) and thyroid and parathyroid glands were removed: one lobe was prepared for conventional pathological examination and the other lobe for electron microscopy observed by three experienced pathological experts. Twenty-four samples were prepared for conventional histology and there were no alterations reported in any group. Due to technical problems, only 21 samples were observed by electron microscopy and there were no differences in the ultrastructure of parathyroid and thyroid glands, namely the nuclear pattern, mitochondria, endoplasmic reticulum or secretory granules, in any of the groups. These results confirm the innocuity of near infrared irradiation’, allowing its intraoperative utilization.

Comparing intraoperative parathyroid identification based on surgeon experience versus near infrared autofluorescence detection – A surgeon-blinded multi-centric study

BackgroundNear infrared autofluorescence (NIRAF) detection has previously demonstrated significant potential for real-time parathyroid gland identification. However, the performance of a NIRAF detection device - PTeye® - remains to be evaluated relative to a surgeon's own ability to identify parathyroid glands. MethodsPatients eligible for thyroidectomy and/or parathyroidectomy were enrolled under 6 endocrine surgeons at 3 high-volume institutions. Participating surgeons were categorized based on years of experience. All surgeons were blinded to output of PTeye® when identifying tissues. The surgeon's performance for parathyroid discrimination was then compared with PTeye®. Histology served as gold standard for excised specimens, while expert surgeon's opinion was used to validate in-situ tissues. ResultsPTeye® achieved 92.7% accuracy across 167 patients recruited. Junior surgeons (<5 years of experience) were found to have lower confidence in parathyroid identification and higher tissue misclassification rate per specimen when compared to PTeye® and senior surgeons (>10 years of experience). ConclusionsNIRAF detection with PTeye® can be a valuable intraoperative adjunct technology to aid in parathyroid identification for surgeons.

A Rapid Intraoperative Parathyroid Hormone Assay Based on the Immune Colloidal Gold Technique for Parathyroid Identification in Thyroid Surgery.

ObjectiveA novel immunochromatographic test strip method was developed to detect tissue parathyroid hormone (PTH) using the immune colloidal gold technique (ICGT). The accuracy and application value of this method for intraoperative parathyroid identification were evaluated.MethodsSerum samples were collected to measure PTH by both ICGT and electrochemiluminescence immunoassay (ECLIA). Patients who underwent unilateral and total thyroidectomy were enrolled to evaluate the feasibility and clinical efficacy of rapid intraoperative identification of parathyroid glands via PTH determination using ICGT. Two sample preparation methods, fine needle aspiration (FNA) and tissue block homogenate (TBH), were used for PTH-ICGT analysis.ResultsBablok analysis showed a linear relationship between the serum PTH measurements obtained by ICGT and ECLIA. Non-parathyroid tissues had much lower PTH concentrations (14.8 ± 2.1 pg/ml, n = 97) detected by ICGT, compared to the parathyroid gland tissues (955.3 ± 16.1 pg/ml, n = 79; P < 0.0001), With biopsy results as the standard, ICGT showed higher diagnosis rates as compared with direct visual inspection, for identifying both parathyroid glands (97.4 vs. 78.2%) and non-parathyroid tissues (100 vs. 68.9%). The cut-off values for parathyroid identification by FNA and TBH methods were 63.99 and 136.30 pg/ml, respectively. The detection time was 2 min by TBH method for in vitro tissue detection and 6 min by FNA method for in situ tissue detection, both of which were faster than traditional intraoperative cryopathological examination (usually >30 min). Intraoperative application of ICGT method was associated with higher postoperative serum calcium and blood PTH levels at 1 and 3 months as well as a lower incidence of postoperative transient hypocalcemia, as compared with direct visual inspection.ConclusionPTH-ICGT assay shows high potential as a rapid, novel alternative for intraoperative parathyroid identification.

Initial clinical experiences using the intraoperative probe-based parathyroid autofluorescence identification system-PTeye™ during thyroid and parathyroid procedures.

The Food and Drug Administration has cleared a probe-based near-infrared autofluorescence (NIRAF) detection system called PTeye™ as an adjunct tool for label-free intraoperative parathyroid gland (PG) identification. Since PTeye™ has been investigated only in a "blinded" manner to date, this study describes the preliminary impressions of PTeye™ when used by surgeons without being blinded to the device output. Patients undergoing thyroid and parathyroid procedures were prospectively recruited. Target tissues were intraoperatively assessed with PTeye™. The surgeon's confidence in PG identification was recorded concomitantly with NIRAF parameters that were output in real-time from PTeye™. A retrospective review of prospectively collected data on 83 patients was performed. PTeye™ was used for interrogating 336 target tissues in 46 parathyroid and 37 thyroid procedures. PTeye™ yielded an overall accuracy of 94.3% with a positive predictive value of 93.0% and a negative predictive value of 100%. An increase in confidence for intraoperative PG identification with PTeye™ was observed by all three participating high-volume surgeons, irrespective of their level of accrued surgical experience. Probe-based NIRAF detection with PTeye™ can be a valuable adjunct device to intraoperatively identify PGs for surgeons of varied training and experience.

Primary study of identification of parathyroid gland based on laser-induced breakdown spectroscopy.

The identification and preservation of parathyroid glands (PGs) is a major issue in thyroidectomy. The PG is particularly difficult to distinguish from the surrounding tissues. Accidental damage or removal of the PG may result in temporary or permanent postoperative hypoparathyroidism and hypocalcemia. In this study, a novel method for identification of the PG was proposed based on laser-induced breakdown spectroscopy (LIBS) for the first time. LIBS spectra were collected from the smear samples of PG and non-parathyroid gland (NPG) tissues (thyroid and neck lymph node) of rabbits. The emission lines (related to K, Na, Ca, N, O, CN, C2, etc.) observed in LIBS spectra were ranked and selected based on the important weight calculated by random forest (RF). Three machine learning algorithms were used as classifiers to distinguish PGs from NPGs. The artificial neural network classifier provided the best classification performance. The results demonstrated that LIBS can be adopted to discriminate between smear samples of PG and NPG, and it has a potential in intra-operative identification of PGs.