Evaluation of conventional imaging techniques on preoperative localization in primary hyperparathyroidism

Preoperative localization of single gland disease in primary hyperparathyroidism: a comparative study for preoperative localization with four-dimensional computed tomography, ultrasonography, and technetium-99m-sestamibi single-photon emission computed tomography

Background

Treatment guidelines for primary hyperparathyroidism (PHPT) recommend high-resolution neck ultrasonography (US), technetium-99m-sestamibi single-photon emission computed tomography (99mTc-sestamibi SPECT), and contrast-enhanced four-dimensional computed tomography (4D CT) as image evaluation methods. This study aimed to compare the sensitivity and accuracy of the three image evaluation methods recommended in the guidelines for patients with PHPT and evaluate the utility of 4D CT for preoperative localization in single gland disease.

Methods

A retrospective medical chart review was performed on 41 patients who underwent surgery for single gland disease at the Department of Otorhinolaryngology, Pusan National University Hospital, between January 2021 and March 2023. All the patients underwent preoperative US, 99mTc-sestamibi SPECT, and 4D CT. The location of the abnormal parathyroid lesion, removed during surgery and confirmed by postoperative pathological examination, was used as the reference standard. The sensitivity, specificity, and accuracy of the three imaging evaluations were assessed and compared to the reference standard location.

Results

The sensitivity, specificity, and accuracy of the imaging modalities were as follows: 4D CT, 95.1%, 98.4%, and 97.6%; US, 82.9%, 95.1%, and 92.1%; and 99mTc-sestamibi SPECT, 78.0%, 97.6%, and 92.7%, respectively. Furthermore, a total of nine cases were identified where accurate localization could not be achieved through US and 99mTc-sestamibi SPECT. The presence of coexisting thyroid lesions was significantly correlated with incorrect localization in preoperative US (P<0.05). The small volume of the parathyroid tumor was significantly associated with an increased rate of false-negatives using 99mTc-sestamibi SPECT (P<0.05).

Conclusions

In the preoperative localization of abnormal parathyroid lesions, 4D CT demonstrated higher sensitivity and specificity than US and 99mTc-sestamibi SPECT. 4D CT can accurately localize abnormal parathyroid lesions, even in cases in which both US and 99mTc-sestamibi SPECT yielded incorrect localizations.

The use of computed tomography as a first-line imaging modality in patients with primary hyperparathyroidism

BACKGROUND

The success of minimally invasive parathyroidectomy (MIP) relies on accurate localization of the abnormal parathyroid glands. Concordant findings on ultrasound (US) and ^99mTc-scintigraphy (sestamibi) are currently considered the 'gold standard'. Computed tomography (CT) has also recently been used in preoperative planning. We sought to assess the accuracy of CT for localization of abnormal parathyroid glands in such patients.

METHODS

An audit of 75 patients with primary hyperparathyroidism (PHPT) who underwent neck US and CT between 2017 and 2019 at our center as their first-line imaging.

RESULTS

All 75 patients underwent US and CT and 54 (72.0%) also had sestamibi. CT alone identified a potential target in all patients, of which the location was correct in 63 (84.0%). The overall combined sensitivity of US and CT was 88% (95% CI 78-94) and was higher than the combined sensitivity of US and sestamibi (65% [95% CI 53-76]; p < 0.001). Twenty-one patients (28.0%) had an ectopic gland, and the sensitivity of US and CT was 86% (95% CI 64-96) versus US and sestamibi (57% [95% CI 34-77]; p = 0.016). For adenomas < 1.0 g (n = 36; 48%), the accuracy of CT was 81% (95% CI 64-91) compared with 62% (95% CI 44-77) for US and sestamibi (p = 0.04). The correct preoperative diagnosis of multiglandular disease (n = 9; 12%) seemed to be the most difficult, with similar accuracy for US and sestamibi (40% [95% CI 14-73]) and US and CT (50% [95% CI 20-80]) (p > 0.99).

CONCLUSION

The combination of US and CT was able to correctly identify the location of the abnormal parathyroid in 88% of patients and, in comparison with US and sestamibi, had better diagnostic accuracy, especially for smaller and ectopic adenomas. This finding suggests that US and CT could be considered as a first-line imaging modality in patients with PHPT considered for MIP.

Direct Comparison of Preoperative Imaging Modalities for Localization of Primary Hyperparathyroidism: A Systematic Review and Network Meta-analysis

Importance

Accurate preoperative localization of primary hyperparathyroidism (pHPT) is an important and challenging issue for a successful parathyroidectomy. Although new imaging modalities have been introduced during the past decade, direct comparative studies on advanced imaging techniques are limited.

Objective

To compare the performance of different preoperative imaging modalities for the localization of pHPT by performing a network meta-analysis (NMA).

Data Sources

PubMed, Embase, and the Cochrane Library were searched from the earliest available indexing date through September 28, 2020.

Study Selection

The inclusion criteria were diagnostic tests with sensitivities of 2 or more different preoperative imaging modalities for the same indivduals.

Data Extraction and Synthesis

Two researchers independently reviewed the literature according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses extension statement of health care intervention guidelines for network meta-analyses.

Main Outcomes and Measures

After classifying various imaging modalities into 8 representative imaging categories, the pooled estimation between the odds ratio and 95% credible intervals (CrIs) was calculated in the sensitivity for localization of pHPT. The surface under the cumulative ranking curve (SUCRA) values were obtained to calculate the probability of each imaging modality being the most effective diagnostic method.

Results

A total of 8495 patients from 119 direct comparative studies using 2 or more imaging modalities for localization of pHPT were included. The sensitivity of choline positron emission tomography and computed tomography (PET-CT) was significantly higher than that of technetium 99m sestamibi single-photon emission computed tomography (MIBI SPECT) in both patient-based and lesion-based analyses (patient-based analysis: odds ratio, 5.22; 95% CrI, 2.36-11.80; lesion-based analysis: odds ratio, 17.70; 95% CrI, 5.79-60.10). Among 8 representative imaging modality categories, choline PET-CT showed the highest SUCRA value in both patient-based and lesion-based analyses. In patient-based analysis after 2010, choline PET-CT showed the highest SUCRA value, followed by the CT category, although MIBI SPECT had the highest SUCRA value in analysis before 2009.

Conclusions and Relevance

The results from this network meta-analysis suggest that choline PET-CT showed the best performance in both patient-based and lesion-based analyses and that choline PET-CT would be the best preoperative imaging modality for localization of pHPT.

Pre-operative imaging workup for surgical intervention in primary hyperparathyroidism: A tertiary referral center experience

PURPOSE

Preoperative imaging in patients with primary hyperparathyroidism provides important localization information, allowing the surgeon to perform a focused surgery. However there are no evidence-based guidelines suggesting which preoperative imaging should be used, resulting in a risk of excessive prescription of exams and waste of economic resources. The main purpose of this study was to describe our experience on the performance of various imaging techniques for the preoperative localization of abnormal parathyroid gland/s, with a focus on the sensitivity and specificity of each technique. Secondly, we carried out an analysis of the cost utility of each technique in order to determine the most clinical and cost-effective combination of localization studies.

MATERIALS AND METHODS

Records of 336 patients who underwent parathyroidectomy were retrospectively examined comparing imaging and intraoperative/histopathologic findings to evaluate the accuracy in parathyroid detection of each imaging technique. Costs were determined by regional health system reimbursement.

RESULTS

We found that the sensitivity of color Doppler US was significantly higher than SPECT (p 0,023), while the sensitivity of 4D-CT was significantly better than US (p 0,029) and SPECT (p 0,0002).

CONCLUSIONS

In experienced hands color Doppler US is a highly sensitive technique especially in patients with no thyroid diseases. In patients with concomitant thyroid pathology, the combination of US and 4D-CT represents a reliable localization technique.

Preoperative and Intraoperative Methods of Parathyroid Gland Localization and the Diagnosis of Parathyroid Adenomas

Accurate pre-operative determination of parathyroid glands localization is critical in the selection of minimally invasive parathyroidectomy as a surgical treatment approach in patients with primary hyperparathyroidism (PHPT). Its importance cannot be overemphasized as it helps to minimize the harmful side effects associated with damage to the parathyroid glands such as in hypocalcemia, severe hemorrhage or recurrent laryngeal nerve dysfunction. Preoperative and intraoperative methods decrease the incidence of mistakenly injuring the parathyroid glands and allow for the timely diagnosis of various abnormalities, including parathyroid adenomas. This article reviews 139 studies conducted between 1970 and 2020 (49 years). Studies that were reviewed focused on several techniques including application of carbon nanoparticles, carbon nanoparticles with technetium sestamibi (99m Tc-MIBI), Raman spectroscopy, near-infrared autofluorescence, dynamic optical contrast imaging, laser speckle contrast imaging, shear wave elastography, and indocyanine green to test their potential in providing proper parathyroid glands' localization. Apart from reviewing the aforementioned techniques, this study focused on the applications that helped in the detection of parathyroid adenomas. Results suggest that applying all the reviewed techniques significantly improves the possibility of providing proper localization of parathyroid glands, and the application of indocyanine green has proven to be the 'ideal' approach for the diagnosis of parathyroid adenomas.

Added value of ultrasonography and Tc-99m MIBI SPECT/CT combined protocol in preoperative evaluation of parathyroid adenoma

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Concomitant use of ultrasonography and MIBI-SPECT/CT is highly recommended for better depiction of parathyroid adenoma.

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It also helps in accurate localization of parathyroid adenoma especially those of ectopic location.

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It will provide better success for parathyroid exploration and minimally invasive surgery.

Purpose

Evaluating the diagnostic performance of combined protocol of ultrasonography and Tc-99 m MIBI SPECT/CT in preoperative depiction and localization of parathyroid adenoma.

Methods and materials

60 patients were enrolled in this retrospective study who had primary hyperparathyroidism and parathyroidectomy for parathyroid adenoma, all of them underwent ultrasonography examination of parathyroid gland and MIBI SPECT/CT for exact pre-operative localization of parathyroid adenoma, surgical and pathological results were used as standard reference then sensitivity, specificity and accuracy for each modalility and for combined protocol of both modalities was calculated.

Results

The sensitivity, specificity and accuracy were highest with combined protocol of ultrasonography and MIBI-SPECT/CT (87 %), (71 %) and (85 %) respectively and lowest sensitivity, specificity and accuracy with ultrasonography alone (76 %), (63 %) and (73 %) respectively while (83 %), (66 %) and (80 %) with MIBI-SPECT/CT alone.

Conclusion

Concomitant use of ultrasonography and MIBI SPECT/CT is highly recommended for better preoperative depiction and localization of parathyroid adenoma.

Localization of parathyroid adenomas using 11C-methionine pet after prior inconclusive imaging

PURPOSE

Minimally invasive parathyroidectomy (MIP) is the recommended treatment in primary hyperparathyroidism (pHPT) for which accurate preoperative localization is essential. The current imaging standard consists of cervical ultrasonography (cUS) and MIBI-SPECT/CT. 11C-MET PET/CT has a higher resolution than MIBI-SPECT/CT. The aim of this study was to determine the diagnostic performance of 11C-MET PET/CT after initial inconclusive or negative localization.

METHODS

We performed a retrospective single center cohort study of patients with pHPT undergoing parathyroid surgery after prior negative imaging and later localization by means of 11C-MET PET/CT between 2006 and 2014. Preoperative localization by 11C-MET PET/CT was compared with later surgical localization, intraoperative quick PTH (IOPTH), duration of surgery, histopathology, and follow-up data. Also, differences in duration of surgery between the groups with and without correct preoperative localization were analyzed.

RESULTS

In 18/28 included patients a positive 11C-MET-PET/CT result corresponded to the surgical localized adenoma (64%). In 3/28 patients imaging was false positive and no adenoma was found. In 7/28 patients imaging was false negative at the side of the surgically identified adenoma. Sensitivity of 11C-MET PET/CT was 72% (18/25). Duration of surgery of correctly localized patients was significantly shorter compared to falsely negative localized patients (p = 0.045).

CONCLUSION

In an intention to treat 11C-MET-PET/CT correctly localized the parathyroid adenoma in 18/28 (64%) patients, after previous negative imaging. A preoperatively correct localized adenoma leads to a more focused surgical approach (MIP) potentially reducing duration of surgery and potentially healthcare costs.

Diagnosis performance of 99mTc-MIBI and multimodality imaging for hyperparathyroidism

This study aimed to examine the diagnosis performance of ^99mTc-methoxyisobutylisonitrisonitrile (^99mTc-MIBI) and multimodality imaging [ultrasound, single-photon emission computed tomography/computed tomography (SPECT/CT)] for hyperparathyroidism (HPT). From Nov. 2009 to Dec. 2015, clinical data of a total of 43 HPT patients (16 males and 27 females; 26-70 years old, average age: 51.60±10.66 years old) were retrospectively analyzed. Among them, 19 patients with primary hyperparathyroidism (PHPT) underwent ^99mTc-MIBI planar imaging, 24 [15 with PHPT and 9 with secondary hyperparathyroidism (SHPT)] underwent SPECT/CT hybrid imaging, and 41 (33 with PHPT and 8 with SHPT) had neck ultrasound imaging. Final diagnosis was determined by pathological examination after surgery. The positive rate was compared between different imaging modalities, and the correlation analysis was conducted between imaging results and lesion size or serum parathyroid hormone (PTH) level. The results showed that the total positive rates of ^99mTc-MIBI imaging, ultrasound, and the two combined imaging in the 43 HPT cases were 90.70% (39/43), 58.54% (24/41), and 100% (41/41), respectively. According to lesion numbers, the positive rates were 79.10% (53/67), 53.23% (33/62), and 88.71% (55/62), respectively. SPECT/CT hybrid images were positive in all the 24 patients who underwent this examination. The mean maximum diameters of the lesions in ^99mTc-MIBI positive and negative patients were 1.96±0.95 cm and 1.36±0.67 cm respectively, with statistically significant difference noted (P=0.03). The T/NT of ^99mTc-MIBI imaging at the early phase was correlated positively with serum PTH level (r=0.40, P=0.01). The T/NT of ^99mTc-MIBI imaging at both the early phase and the delay phase was correlated positively with lesion size (r=0.51, and r=0.45, respectively; P<0.01 for both). It was concluded that ^99mTc-MIBI imaging presents significant value for location diagnosis of HPT, especially when combined with SPECT/CT hybrid imaging or ultrasound. The ^99mTc-MIBI uptake correlates positively with serum PTH level and lesion size.

Evaluation of the minimally invasive parathyroidectomy in patients with primary hyperparathyroidism: A retrospective cohort study

INTRODUCTION

An accurate differential diagnosis between single adenoma (SA) and multiglandular disease (MGD) remains difficult in Technetium-99m sestamibi scintigraphy (MIBI)-negative patients with primary hyperparathyroidism (PHPT). The aim of the present study was to evaluate the minimally invasive parathyroidectomy (MIP) in patients with PHPT.

METHODS

Clinical records of 48 patients who underwent neck exploration between November 2002 and June 2012 in Kochi Medical School Hospital were reviewed retrospectively to identify candidates that underwent for MIP which was defined as the selective removal of a SA using less invasive surgery.

RESULTS

The preoperative detection rate of lesions using ultrasonography, MIBI, computed tomography, and magnetic resonance imaging was 90%, 83%, 76%, and 55%, respectively. Although all 39 patients in the MIBI-positive group were diagnosed with an SA and subsequently underwent curative MIP, 3 patients in MIBI-negative group (n = 6) were MGD, who underwent neck exploration. Preoperative mean intact parathyroid hormone (419 pg/ml vs. 149 pg/ml; P < 0.01) and alkaline phosphatase levels (746 U/l vs. 277 U/l; P < 0.01) were significantly higher in the SA than MGD group.

CONCLUSIONS

In MIBI-negative patients with indications for surgery, MIP should not be carried out without a clear localization of SA, or in MGD.

The role of ultrasound and nuclear medicine methods in the preoperative diagnostics of primary hyperparathyroidism

Primary hyperparathyroidism (PH) represents one of the most common endocrine diseases. In most cases, the disorder is caused by parathyroid adenomas. Bilateral neck exploration has been a widely used treatment method for adenomas since the 20's of the twentieth century. In the last decade, however, it has been increasingly replaced by a minimally invasive surgical treatment. Smaller extent, shorter duration and lower complication rate of such a procedure are emphasized. Its efficacy depends on a precise location of parathyroid tissue during the preoperative imaging. Scintigraphy and ultrasound play a major role in the diagnostic algorithms. The efficacy of both methods has been repeatedly verified and compared. The still-current guidelines of the European Association of Nuclear Medicine (2009) emphasize the complementary role of scintigraphy and ultrasonography in the preoperative diagnostics in patients with primary hyperparathyroidism. At the same time, attempts are made to improve both these techniques by implementing new study protocols or innovative technologies. Publications have emerged in the recent years in the field of ultrasonography, whose authors pointed out the usefulness of elastography and contrast media. Nuclear medicine studies, on the other hand, focus mainly on the assessment of new radiotracers used in the positron emission tomography (PET). The aim of this article is to present, based on literature data, the possibilities of ultrasound and scintigraphy in the preoperative diagnostics in patients with primary hyperparathyroidism. Furthermore, the main directions in the development of imaging techniques in PH patients were evaluated.