Diagnostic Performance of 99 mTc-Sestamibi SPECT/CT and 18F-Choline PET/CT in Locating Hyperfunctioning Parathyroid Glands in Patients with Primary Hyperparathyroidism.

This study aimed to assess the diagnostic performance of 99mTc-sestamibi SPECT/CT and 18F-choline PET/CT in detecting hyperfunctioning parathyroid glands in patients undergoing surgery for primary hyperparathyroidism (PHPT). A retrospective analysis was conducted on patients who underwent PHPT-related surgery between April 2019 and May 2022. The study focused on patients undergoing either 99mTc-sestamibi SPECT/CT (81 patients) or 18F-choline PET/CT (33 patients) scans before surgery to pinpoint hyperfunctioning parathyroid gland(s). In the majority of patients, 18F-choline PET/CT was performed after negative or inconclusive findings on 99mTc-sestamibi SPECT/CT. Pathohistological reports were utilized as the reference standard for evaluating the accuracy of the imaging findings. The study encompassed 83 patients (70 females, 84.3%) with an average age of 57.2 years (24-80 years). The pathohistological analysis identified a total of 98 glands. In a per-lesion analysis, the detection rate of 99mTc-sestamibi SPECT/CT was 57% (95% CI 45.3-68.1), while the detection rate of 18F-choline PET/CT was 90.3% (95% CI 74.3-98.0). The results of our study showed the significant usefulness of 18F-choline PET/CT in patients with negative or inconclusive results of 99mTc-sestamibi SPECT/CT in accurately locating hyperfunctioning parathyroid glands in PHPT patients.

11C-Methionine PET/CT (C-MET) is a promising method in detecting abnormal parathyroid glands in patients with primary hyperparathyroidism (PHPT). The first aim of the study was to evaluate which is the diagnostic role of C-MET in patients with PHPT and inconclusive pre-operative imaging. Second, we aimed to investigate whether C-MET semi-quantitative parameters may reflect biochemical and histological characteristics of involved glands. Patients with PHPT, undergoing C-MET after an inconclusive pre-operative imaging and having a parathyroid surgery, were retrospectively included. C-MET visual and semi-quantitative assessment was performed. Parameters, as SUVmax, SUVpeak, SUVmean, functional lesion volume (FLV) and total lesion activity (TLA), were measured for each detected lesion; SUVmean, FLV and TLA were calculated on 40-90% thresholds of SUVmax to define SUVmean40-90, FLV40-90 and TLA40-90, respectively. Results were correlated with patients' clinical-laboratory (calcium and PTH values) and histological data (size and weight of excised glands). Mann-Whitney test was used and P value < 0.05 was considered significant. Thirty-eight patients (36 female, age: 57.69 ± 15.13years) were included. Pre-operative median calcium and PTH values were 11.1mg/dl [interquartile range (IQR) 10.6-11.5] and 154.6pg/ml (IQR 101.8-227.0), respectively. C-MET showed a parathyroid uptake in 30 out of thirty-eight patients (78.9%). Among 42 nodules excised, C-MET correctly detected the side of the neck (right/left) in 30/42 with sensitivity, specificity and accuracy of 79, 75 and 79%, respectively. C-MET correctly identified the exact position (superior/inferior) in 27/42 with sensitivity, specificity and accuracy of 75, 50 and 71%, respectively. SUVpeak, FLV50-70 and TLA40-70 were significantly (P < 0.05) higher in patients with higher PTH results. The histological size resulted significantly (P < 0.05) higher in abnormal glands with higher SUVmax, SUVpeak, FLV40-80 and TLA40-90, the weight was higher in glands with higher SUVpeak, SUVmean40-50, FLV40-80 and TLA40-90. C-MET showed a good performance in detecting hyperfunctioning parathyroid glands in PHPT patients with inconclusive pre-operative imaging. Semi-quantitative PET-derived parameters closely correlated with PTH as well as with size and weight of the excised gland, thus reflecting some biochemical and histological characteristics of involved glands.

Primary hyperparathyroidism (pHPT) is a common endocrine disorder characterized by one or more hyperfunctioning parathyroid glands. Definitive surgical treatment demands precise preoperative localisation of hyperfunctioning parathyroid tissue. The purpose of our study is to assess the value of 18F-fluorocholine positron emission tomography (PET/CT) in preoperative localisation of hyperfunctioning parathyroid glands in patients with biochemically confirmed pHPT and negative or inconclusive cervical ultrasonography and 99mTc-MIBI scintigraphy. Our study included 167 patients with biochemically confirmed pHPT and negative or inconclusive cervical ultrasonography and 99mTc-MIBI scintigraphy. In our study 18F-fluorocholine PET/CT detection rate was 92.81% (155/167) with 182 lesions identified. Overall sensitivity, specificity, accuracy, and positive predictive value (PPV) on a per-lesion analysis were 100%, 75%, 95.33%, and 94.74%. Ninety (90/95) lesions were 18F-fluorocholine PET/CT true positive. A total of 86 patients underwent surgical procedures in which 95 histological lesions were removed. Histology revealed 60 adenomas, 25 hyperplasias, 5 lesions described as inconclusive parathyroid tissue, benign lymph node tissue in 4 lesions and 1 false-positive lesion was follicular thyroid adenoma. After surgery, all patients had PTH serum values measured (15min after extirpation or during immediate postoperative recovery). Mean PTH serum values in patients with successful surgery decreased by an average of 62.54% (preoperative PTH 14.74 ± 8.54pmol/L to 6.3 ± 6.8pmol/L). 18F-fluorocholine PET/CT is an accurate, fast, and highly sensitive method for identifying the localization of overactive parathyroid glands in patients with primary hyperparathyroidism.

To train and validate machine learning-derived clinical decision algorithm (MLCDA) for the diagnosis of hyperfunctioning parathyroid glands using preoperative variables to facilitate surgical planning. This retrospective study included 458 consecutive primary hyperparathyroidism (PHPT) patients who underwent combined 4D-CT and sestamibi SPECT/CT (MIBI) with subsequent parathyroidectomy from February 2013 to September 2016. The study cohort was divided into training (first 400 patients) and validation sets (remaining 58 patients). Sixteen clinical, laboratory, and imaging variables were evaluated. A random forest algorithm selected the best predictor variables and generated a clinical decision algorithm with the highest performance (MLCDA). The MLCDA was trained to predict the probability of a hyperfunctioning vs normal gland for each of the four parathyroid glands in a patient. The reference standard was a four-quadrant location on operative reports and pathology. The accuracy of MLCDA was prospectively validated. Of 16 variables, the algorithm selected 3 variables for optimal prediction: combined 4D-CT and MIBI using (1) sensitive reading, (2) specific reading, and (3) cross-product of serum calcium and parathyroid hormone levels and outputted an MLCDA using five probability categories for hyperfunctioning glands. The MLCDA demonstrated excellent accuracy for correct classification in the training (4D-CT + MIBI: 0.91 [95% CI: 0.89-0.92]) and validation sets (4D-CT + MIBI: 0.90 [95% CI: 0.86-0.94]. Machine learning generated a clinical decision algorithm that accurately diagnosed hyperfunctioning parathyroid glands through classification into probability categories, which can be implemented for improved preoperative planning and convey diagnostic certainty. Question Can an MLCDA use preoperative variables for the diagnosis of hyperfunctioning parathyroid glands to facilitate surgical planning? Findings The developed MLCDA demonstrated excellent accuracy for correct classification in the training (0.91 [95% CI: 0.89-0.92]) and validation sets (0.90 [95% CI: 0.86-0.94]). Clinical relevance Using standard preoperative variables, an MLCDA for diagnosing hyperfunctioning parathyroid glands can be implemented to improve preoperative parathyroid localization and included in radiology reports forsurgical planning.

BackgroundCinacalcet treatment for secondary hyperparathyroidism (SHPT) has demonstrated parathyroid size regression and morphological changes, such as cystic degeneration and hypovascularisation, on ultrasonography.; However, there have been very few reports regarding...

Technetium-99m methoxy isobutyl isonitrile (Tc-99m MIBI) scintigraphy has been reported to be at least as reliable as thallium-technetium subtraction imaging in the preoperative localization of hyperplastic parathyroid glands in patients with renal failure. Reports have suggested that 50% of glands can be identified correctly by this method. The aim of this study was to improve on previous results and demonstrate that Tc-99m MIBI imaging has an important place in the preoperative work-up of these patients. Eighteen patients on renal replacement therapy were studied. All had tertiary hyperparathyroidism and had Tc-99m MIBI imaging prior to parathyroidectomy. A refined reporting method was employed. The imaging results were compared to the subsequent surgical and histological findings. In the 12 patients in whom serum parathyroid hormone levels fell postoperatively to within or below the normal range, 38 of 46 glands (82.6%) were correctly identified and located in the correct quadrant of the thyroid gland. There were two false positive results where the imaging predicted glands not subsequently found by the surgeon. In the patients who had post-operative hyperparathyroidism, repeat Tc-99m MIBI imaging was able to locate accurately the site of the residual parathyroid tissue. Tc-99m MIBI imaging is able to identify more than 80% of hyperplastic parathyroid glands in renal failure patients if this reporting process is used, and locate them in the correct quadrant of the thyroid gland. Tc-99m MIBI imaging is of particular value when re-exploration of the neck is required for post-parathyroidectomy hyperparathyroidism. These results represent a significant improvement on the sensitivity of this imaging technique when compared to previous published data.

BackgroundRenal hyperparathyroidism is a common complication of chronic kidney disease (CKD) or end-stage renal disease (ESRD) characterized by elevated parathyroid hormone levels secondary to derangements in the homeostasis of calcium, phosphate, and vitamin D. Rapid correction of severe and prolonged hyperparathyroidism by surgical parathyroidectomy in long-term hemodialysis patients occasionally causes hungry bone syndrome. These patients then exhibit severe and long-lasting secondary or tertiary hyperparathyroidism with high bone turnover.Case presentationWe report a case of recurrent tertiary hyperparathyroidism after total parathyroidectomy due to supernumerary parathyroid gland in a patient with long-term hemodialysis. Supplementation with intravenous calcium, oral calcium, and vitamin D immediately after patient surgery helps to prevent and treat hungry bone syndrome.ConclusionsWe should prompt a search for the supernumerary parathyroid glands in ESRD patients, who have recurrent or persistent hyperparathyroidism after total parathyroidectomy. ESRD patients are more likely to develop hungry bone syndrome after parathyroidectomy. Prevention and treatment of hungry bone syndrome may be required after ectopic parathyroidectomy in clinical practice.

Background/Aim. Ultrasonography is a cheap, easily available and convenient method for diagnosis. The aims of this study were: to determine the utility of ultrasonography for preoperative identification and localization of enlarged parathyroid glands (PTG) in patients with different forms of hyperparathyroidism (HPT); to examine the frequency of PTG detection in patients previously non-suspected for HPT but having symptoms relevant to the disease; to determine sensitivity and positive predictive value (PPV) of ultrasonography for identification of PTG in HPT and to compare obtained results with those obtained by scintigraphy. Methods. This investigation was designed as a retrospective?prospective study. The total number of patients undergoing ultrasonography prior to surgery was 179 and the number of those subjected to scintigraphy, mostly by the 201Tl/99mTc method, was 112. The patients (52 male, 128 female) were divided into the following four groups: group A ? patients with primary (p)HPT (n = 78); group B ? patients with secondary (s)HPT (n = 47); group C ? patients with tertiary (t)HPT (n = 13); group D ? patients with unrecognized (u)HPT, but with anamnestic data implying the disease (n = 42). High resolution ultrasonography was performed by a single experienced observer. Diagnosis of HPT was based on characteristic clinical and biochemical parameters. Final proof of HPT diagnosis was surgery followed by histopathological examination. Results. Ultrasonography detected enlarged PTG in 93.85% of total patients, whereas scintigraphy uncovered 75.89% of positive cases (p &lt; 0.05). The total number of positive PTG detected by ultrasonography was 211 vs 225 detected by surgery (sensitivity ? 95.9%; PPV ? 99.4%). Histopathology confirmed the predominance of adenoma in the A and D groups in comparison with the B group of patients having PTG hyperplasia. The group C was characterized by the presence of adenomas in hyperplastic PTG. The mean size of PTG measured by ultrasonography was 17.59 ? 8.0 mm (n = 164) vs 18.36 ? 8.54 mm (n = 179) measured after surgery. Ultrasonography proved itself as an accurate technique in all HPT groups, regarding its high sensitivity (range 93.6?100%) and PPV (95.6?100%). In contrast, scintigraphy was shown to be less reliable, especially in the sPTH group (sensitivity: 51.7%; PPV: 78.4%). Conclusion. Ultrasonography is more sensitive and accurate method for pre-operative localization of PTG in comparison with 201Tl/99mTc scintigraphy. It can be also efficiently used for detection of PTG and diagnosis of HPT in patients previously not suspected for this disease.

The frequency of intrathymic parathyroid glands (IPGs) in patients undergoing parathyroidectomy for renal hyperparathyroidism (rHPT) varies considerably between 14.8% and 45.3%. Total parathyroidectomy with autotransplantation and subtotal parathyroidectomy are the most accepted surgical procedures to treat patients with rHPT. However, routine bilateral cervical thymectomy (BCT) is still discussed, although controversially. From a prospective database of patients who underwent parathyroid surgery for rHPT between 1975 and 2009, patients with routine BCT at initial PTX were further analyzed regarding the frequency of ectopic and supernumerary IPGs. Duration of hemodialysis and stage of chronic kidney disease were correlated with the frequency of supernumerary IPGs to elucidate a potential role of long-standing proliferation stimuli to any surplus parathyroid tissue. Initial parathyroidectomy with BCT was performed in 461 patients. IPGs were resected in 205 of them (44.5%). They were ectopic in 181 (39.3%) and supernumerary in 30 patients (6.5%). The frequency of supernumerary IPGs in patients on permanent hemodialysis was 7.4% (29/392), 3.9% (1/26) in predialysis patients, and 0% (0/43) in patients after successful kidney transplantation. This differences reached no statistical significance. BCT is essential in patients with fewer than four parathyroid glands identified at typical positions. Because of the low frequency of supernumerary IPGs and a suspected low proliferation stimulus, the relevance of BCT after resection of four glands in predialysis patients and those after successful kidney transplantation must be questioned. Nevertheless, routine BCT seems to be acceptable and can be recommended in patients on permanent hemodialysis not awaiting kidney transplantation until proven otherwise by prospective trials.

Objective: This study aims to compare the sensitivity of dual phase (non-contrast and arterial) versus single phase (arterial) CT for detection of hyper-functioning parathyroid glands in patients with primary hyperparathyroidism. Methods: The CT scans of thirty-two patients who have biochemical evidence of primary hyperparathyroidism, pathologically proven parathyroid adenomas, and pre-operative multiphase parathyroid imaging were evaluated retrospectively in order to compare the adequacy of single phase vs. dual phase CT scans for the detection of parathyroid adenomas. Results: The parathyroid adenomas were localized in 83% of cases on single arterial phase CT and 80% of cases on dual phase CT. The specificity for localization of parathyroid tumor was 96% for single phase CT and 97% for dual phase CT. The results were not significantly different (p=0.695). These results are similar to those found in the literature for multiphase CT of 55-94%. Conclusions: Our study supports the use of a single arterial phase CT for the detection of hyperfunctioning parathyroid adenomas. Advances in knowledge: A single arterial phase CT has similar sensitivity for localizing parathyroid adenomas as dual phase CT and significantly reduces radiation dose to the patient.

ObjectiveThis study aims to compare the sensitivity of dual phase (non-contrast and arterial) versus single phase (arterial) CT for detection of hyper-functioning parathyroid glands in patients with primary hyperparathyroidism.MethodsThe CT scans of thirty-two patients who have biochemical evidence of primary hyperparathyroidism, pathologically proven parathyroid adenomas, and pre-operative multiphase parathyroid imaging were evaluated retrospectively in order to compare the adequacy of single phase vs. dual phase CT scans for the detection of parathyroid adenomas.ResultsThe parathyroid adenomas were localized in 83% of cases on single arterial phase CT and 80% of cases on dual phase CT. The specificity for localization of parathyroid tumor was 96% for single phase CT and 97% for dual phase CT. The results were not significantly different (p = 0.695). These results are similar to those found in the literature for multiphase CT of 55–94%.ConclusionsOur study supports the use of a single arterial phase CT for the detection of hyperfunctioning parathyroid adenomas. Advances in knowledge: a single arterial phase CT has similar sensitivity for localizing parathyroid adenomas as dual phase CT and significantly reduces radiation dose to the patient.

Tc-99m sestamibi parathyroid imaging was performed in 28 patients with chronic renal failure to localize abnormal parathyroid glands in patients receiving hemodialysis, and compared the localization with ultrasonography and magnetic resonance (MR) imaging. Methods: We imaged 28 patients with secondary hyperparathyroidism using Tc-99m sestamibi (about 600 MBq) at 10 min and 2–3 h following radiotracer injection. In addition, mediastinal images were recorded at approximately 1 h following injection to identify ectopic parathyroid glands. All patients also were evaluated with ultrasonography and MR imaging. Results: Tc-99m sestamibi scans demonstrated focal uptake in 60 glands of the 28 patients, and was categorized as slight uptake in 71.7% (43/60), and intense uptake in 28.3% (17/60). Seventeen of the 28 patients underwent parathyroidectomy. A total of 64 glands were resected. Sestamibi imaging was more sensitive for localizing abnormal parathyroid glands than ultrasonography or MR imaging. Histologic evaluation of 27 resected parathyroid glands revealed that the number of oxyphil or chief cells was not proportional to sestamibi uptake. Conclusion: Our data indicate that Tc-99m sestamibi imaging should be used initially to localize abnormal parathyroid glands in hemodialysis patients with secondary hyperparathyroidism, prior to MR imaging or ultrasonography. Sestamibi uptake in parathyroid glands may not correlate with the degree of hypercellularity of oxyphil cells.

Ultrasound-Guided Percutaneous Laser Ablation in Patients With Primary Hyperparathyroidism

The efficacy of MR imaging in identifying abnormal parathyroid glands in patients with recurrent hyperparathyroidism after surgery was investigated. Findings on preoperative T1- and T2-weighted MR images in 44 patients with recurrent hyperparathyroidism were prospectively evaluated and compared with surgical/pathologic results in all patients. A blinded retrospective analysis of the MR findings comparing T1- or T2-weighted images alone and in combination for detection of abnormal parathyroid glands also was performed. Seventy-four percent of surgically proved abnormal parathyroid glands were detected prospectively and 65% were detected retrospectively on MR images. The combination of T1- and T2-weighted images increased the sensitivity for detection. The sensitivity for detection of abnormal glands was 72% in the neck and 86% in the mediastinum. The sensitivities for detecting parathyroid adenomas (80%) and hyperplastic glands (69%) were not significantly different. There was no threshold volume for detection of lesions with MR imaging. Both intrathyroid parathyroid adenomas were missed on MR images. Abnormal glands could not be differentiated from lymph nodes on MR images in three cases. MR imaging is a useful technique for detecting abnormal parathyroid glands preoperatively in patients with recurrent hyperparathyroidism after surgery. The combination of T1- and T2-weighted images increases the sensitivity for detection.

Introduction. Primary hyperparathyroidism is one of the most common diseases of the endocrine system, after diabetes mellitus and thyroid pathologies. Early diagnosis and treatment of primary hyperparathyroidism allow avoiding severe damage to the bones, kidneys, other organs, thereby reducing the incidence of disability and improving the patients quality of life. The only radical treatment for primary hyperparathyroidism is the surgical removal of the pathologically altered, hyperfunctioning parathyroid glands.The study objective – to increase the efficiency of preoperative topical diagnosis and intraoperative navigation of parathyroid glands.Materials and methods. 200 patients with laboratory-verified primary hyperparathyroidism, who underwent preoperative topical diagnostics (ultrasound, planar scintigraphy and single-photon emission computed tomography, combined with computed tomography (SPECT / CT), in some cases supplemented with contrast enhanced CT with / or fine needle aspiration biopsy with flushing from a needle on for parathyroid hormone) and received surgical treatment, in period from 2017 to 2020. A single-stage, open-label comparative study was carried out, including clinical, laboratory and instrumental data of patients. The follow-up period after surgery for primary hyperparathyroidism was at least 6 months.Results. From 200 included patients, surgical treatment in the amount of minimally invasive parathyroidectomy was performed in 189 patients. As a result of the analysis of the diagnostic accuracy, for a combination of ultrasound and SPECT/CT with augmented contrast enhanced CT, the overall accuracy in visualizing of parathyroid glands was 99 % (95 % confidence interval (CI): 97–100), diagnostic specificity 77 % (95 % CI: 54–100), sensitivity 100 % (95 % CI: 98–100), the predictive value of positive and negative results was 98 % (95 % CI: 97–100) and 100 % (95 % CI: 98–100) respectively.Conclusion. The results allowed us to develop an algorithm for preoperative topical diagnosis of parathyroid glands in patients with laboratory-verified primary hyperparathyroidism and indications for surgical treatmen. We recommend to perform ultrasound of the thyroid and parathyroid glands in all patients at the first stage, in the absence of evident changes in the thyroid gland, at the second stage – scintigraphy and SPECT / CT with 99mTc-MIBI; in cases with significant concomitant functional or structural pathology of the thyroid gland – contrast enhanced CT; if necessary, supplementing fine needle aspiration biopsy with flushing from a needle on for parathyroid hormone.