Combined application of ultrasound and SPECT/CT has incremental value in detecting parathyroid tissue in SHPT patients

Recurrent renal secondary hyperparathyroidism caused by supernumerary mediastinal parathyroid gland and parathyromatosis: A case report

Background

Surgical parathyroidectomy (PTX) is necessary for patients with severe and progressive secondary hyperparathyroidism (SHPT) refractory to medical treatment. Recurrence of SHPT after PTX is a serious clinical problem. Both supernumerary mediastinal parathyroid gland and parathyromatosis are the rare causes of recurrent renal SHPT. We report a rare case of recurrent renal SHPT due to supernumerary mediastinal parathyroid gland and parathyromatosis.

Case presentation

A 53-year-old man underwent total parathyroidectomy with autotransplantation due to the drug-refractory SHPT 17 years ago. In the last 11 months, the patient experienced symptoms including bone pain and skin itch, and the serum intact parathyroid hormone (iPTH) level elevated to 1,587 pg/ml. Ultrasound detected two hypoechoic lesions located at the dorsal area of right lobe of the thyroid gland, and both lesions presented as characteristics of hyperparathyroidism in contrast-enhanced ultrasound. ^99mTc-MIBI/SPECT detected a nodule in the mediastinum. A reoperation involved a cervicotomy for excising parathyromatosis lesions and the surrounding tissue and a thoracoscopic surgery for resecting a mediastinal parathyroid gland. According to a histological examination, two lesions behind the right thyroid lobe and one lesion in the central region had been defined as parathyromatosis. A nodule in the mediastinum was consistent with hyperplastic parathyroid. The patient remained well for 10 months with alleviated symptoms and stabilized iPTH levels in the range of 123-201 pg/ml.

Conclusion

Although rare, recurrent SHPT may be caused by a coexistence of both supernumerary parathyroid glands and parathyromatosis, which should receive more attention. The combination of imaging modalities is important for reoperative locations of parathyroid lesions. To successfully treat parathyromatosis, all the lesions and the surrounding tissue must be excised. Thoracoscopic surgery is a reliable and safe approach for the resection of ectopic mediastinal parathyroid glands.

The value of clinical-ultrasonographic feature model to predict the severity of secondary hyperparathyroidism

Objectives

To analyze conventional ultrasound (CUS) and contrast-enhanced ultrasound (CEUS) features in patients with secondary hyperparathyroidism (SHPT) and to evaluate the clinical-ultrasonographic feature based model for predicting the severity of SHPT.

Methods

From February 2016 to March 2021, a total of 59 patients (age 51.3 ± 11.7 years, seCr 797.8 ± 431.7 μmol/L, iPTH 1535.1 ± 1063.9 ng/L) with SHPT (including 181 parathyroid glands (PTGs)) without the history of intact parathyroid hormone (iPTH)-reducing drugs using were enrolled. The patients were divided into the mild SHPT group (mSHPT, iPTH <800 ng/L) and the severe SHPT group (sSHPT, iPTH ≥ 800 ng/L) according to the serum iPTH level. The clinical test data of patients were collected and CUS and CEUS examinations were performed for every patient. Multivariable logistic regression model according to clinical-ultrasonographic features was adopted to establish a nomogram. We performed K-fold cross-validation on this nomogram model and nomogram performance was determined by its discrimination, calibration, and clinical usefulness.

Results

There were 19 patients in the mSHPT group and 40 patients in the sSHPT group. Multivariable logistic regression indicated serum calcium, serum phosphorus and total volume of PTGs were independent predictors related with serum iPTH level. Even though CEUS score of wash-in and wash-out were showed related to severity of SHPT in univariate logistic regression analysis, they were not predictors of SHPT severity (p = 0.539, 0.474 respectively). The nomogram developed by clinical and ultrasonographic features showed good calibration and discrimination. The accuracy and the area under the curve (AUC), positive predictive value (PPV), negative predictive value (NPV) and accuracy of this model were 0.888, 92.5%, 63.2% and 83.1%, respectively. When applied to internal validation, the score revealed good discrimination with stratified fivefold cross-validation in the cohort (mean AUC = 0.833).

Conclusions

The clinical-ultrasonographic features model has good performance for predicting the severity of SHPT.

The role of preoperative ultrasound, contrast-enhanced ultrasound, and 99mTc-MIBI scanning with single-photon emission computed tomography/X-ray computed tomography localization in refractory secondary hyperparathyroidism

OBJECTIVE

The aim of our study was to evaluate the role of preoperative US, CEUS, and 99mTc-MIBI scanning with SPECT/CT in localizing diseased parathyroid glands in cases of refractory secondary hyperparathyroidism (SHPT).

MATERIAL AND METHODS

Using pathological results as the gold standard, we compared the operative findings with the preoperative localization of each modality in 73 nodules and evaluated the accuracy, and sensitivity of each modality and combinations of the four modalities.

RESULTS

The sensitivity of US, CEUS, 99mTc-MIBI and SPECT/CT was 98.59%, 94.37%, 50.70% and 78.87%, respectively. US had the highest sensitivity of the four imaging methods and the diagnostic sensitivity of US and CEUS was superior to that of 99mTc-MIBI (p < 0.001 and p < 0.001) and SPECT/CT (p = 0.001 and p = 0.012). In addition, we found that the sensitivity of the combination of US with CEUS, US with 99mTc-MIBI and/or SPECT/CT, CEUS with 99mTc-MIBI and/or SPECT/CT, US with CEUS and two other imaging modalities (99mTc-MIBI and/or SPECT/CT) was 98.59%, 100%, 95.77%, and 100%, respectively.

CONCLUSIONS

The combination of US with SPECT/CT is the best choice for the comprehensive preoperative localization of glands in refractory SHPT. CEUS can elevate the accuracy of US in differential diagnosis via the interpretation of dynamic microvascular features.

Diagnostic performance of ultrasonography, dual-phase 99mTc-MIBI scintigraphy, early and delayed 99mTc-MIBI SPECT/CT in preoperative parathyroid gland localization in secondary hyperparathyroidism

BACKGROUND

Secondary hyperparathyroidism (SHPT) usually requires parathyroidectomy when drug regimens fail. However, obtaining an exact preoperative map of the locations of the parathyroid glands is a challenge. The purpose of this study was to compare the diagnostic performance of US, dual-phase ^99mTc-MIBI scintigraphy, early and delayed ^99mTc-MIBI SPECT/CT in patients with SHPT.

METHODS

Sixty patients with SHPT who were undergoing dialysis were evaluated preoperatively by US, dual-phase ^99mTc-MIBI scintigraphy, early and delayed ^99mTc-MIBI SPECT/CT. Postoperative pathology served as the gold standard. The sensitivity, specificity, and accuracy were determined for each method. Spearman correlation analysis was used to analyse the correlation of hyperplastic parathyroid calcification with serum alkaline phosphatase (ALP) and parathyroid hormone (PTH).

RESULTS

A total of 229 lesions in 60 patients were pathologically confirmed to be parathyroid hyperplasia, with 209 lesions in typical sites, 15 lesions in the upper mediastinum and 5 lesions in the thyroid. A total of 88.33% (53/60) of patients had four lesions. US, early and delayed ^99mTc-MIBI SPECT/CT had significantly higher sensitivity and accuracy than dual-phase ^99mTc-MIBI scintigraphy (P < 0.001). Furthermore, early ^99mTc-MIBI SPECT/CT had significantly higher sensitivity (P < 0.001) and accuracy (P = 0.001 and P < 0.001) than US and delayed ^99mTc-MIBI SPECT/CT. In patients with ectopic hyperplastic parathyroid glands, the sensitivity of early ^99mTc-MIBI SPECT/CT (90%) was significantly higher than that of US (55%) and dual-phase ^99mTc-MIBI scintigraphy (50%) (P < 0.05). The Spearman correlation results showed a significant albeit weak association between calcification and both serum PTH and ALP (P = 0.002).

CONCLUSION

The ability of early ^99mTc-MIBI SPECT/CT to detect hyperplastic parathyroid glands in patients with SHPT is superior to that of US, dual-phase ^99mTc-MIBI scintigraphy and delayed ^99mTc-MIBI SPECT/CT; furthermore, dual-phase ^99mTc-MIBI SPECT/CT is not essential.

Shear Wave Elastography in Diagnosing Secondary Hyperparathyroidism

This study evaluates the diagnostic value of two-dimensional shear wave elastography (2 D-SWE) technique in the evaluation of hyperplastic parathyroid glands in cases with secondary and tertiary hyperparathyroidism. A total of 59 patients (end-stage renal disease, under supplemental dialysis program) with visible parathyroid hyperplastic glands on ultrasound, confirmed by biochemical assay and scintigraphy, were enrolled; they were examined on grayscale ultrasound and 2 D shear wave elastography. We determined the elasticity index (EI) in the parathyroid gland, thyroid parenchyma and surrounding muscles, and the elasticity ratio of hyperplastic parathyroid glands compared to muscle, specifically sternocleidomastoid muscle. Patients presented fibrocystic bone disease with secondary hyperparathyroidism induced by end-stage chronic kidney disease; being on prolonged chronic dialysis therapy, they had positive sestamibi scintigraphy and high values of serum parathormone (1141.04 pg/mL). Nodules placed posterior to the thyroid capsule that were cystic, had a hypoechoic aspect, and were homogenous with an independent afferent artery were found. Mean EI in the parathyroid gland was 7.83 kPa, the median value in thyroid parenchyma was 13.76 kPa, and mean muscle EI value was 15.78 kPa. The observed mean parathyroid/muscle SWE ratio was 0.5356 and the value for parathyroid/normal thyroid parenchyma was 0.5995. Using receiver operating characteristic (ROC) analysis, we found that EI below 9.74 kPa correctly identifies parathyroid tissue, with a sensitivity of 94.8%, specificity of 90.7%, and accuracy of 92.26% when compared to normal thyroid tissue. Compared with the muscle tissue, we identified that EI below 9.98 kPa has a sensitivity, specificity, and accuracy of 93.8%, 90.7%, and 91.75%, respectively. Ultrasound elastography is a helpful tool in identifying parathyroid hyperplasia in patients with chronic kidney disease. A cutoff value of 9.98 kPa can be used in 2 D-SWE for accurate diagnosis of parathyroid disease.

Parathyromatosis type 2 detected by 99mTc-MIBI SPECT/CT

Parathyromatosis, which is defined as multiple foci of benign hyperfunctioning parathyroid tissue in neck or mediastinum, is a rare but severe cause of persistent/recurrent renal hyperparathyroidism (rHPT) after parathyroidectomy (PTX). It is hard to detect and remove all the foci. We present a case of parathyromatosis in a haemodialysed patient, who had three PTXs for persistent/recurrent rHPT and was free of recurrence during 31-month follow-up after the third PTX. ^99mTc-MIBI SPECT/CT scan prior to the third PTX located all the lesions. The presented case suggests that preoperative ^99mTc-MIBI SPECT/CT is useful for successful surgical removal of parathyromatosis.

Pre-operative Localisation of the Parathyroid Glands in Secondary Hyperparathyroidism: A Retrospective Cohort Study

Complete parathyroidectomy (PTx) is essential during total PTx for secondary hyperparathyroidism (SHPT) to prevent recurrent and persistent hyperparathyroidism. Pre-operative imaging evaluations, including computed tomography (CT), ultrasonography (US), and Tc-99m sestamibi (MIBI) scans, are commonly performed. Between June 2009 and January 2016, 291 patients underwent PTx for SHPT after pre-operative evaluations involving CT, US, and MIBI scans, and the diagnostic accuracies of these imaging modalities for identifying the parathyroid glands were evaluated in 177 patients whose intact parathyroid hormone (PTH) levels were <9 pg/mL after the initial PTx. Additional PTx procedures were performed on 7 of 114 patients whose intact PTH levels were >9 ng/mL after PTx, and the diagnostic validities of the imaging modalities for the remnant parathyroid glands were evaluated. A combination of CT, US, and MIBI scans achieved the highest diagnostic accuracy (75%) for locating bilateral upper and lower parathyroid glands before initial PTx. The accuracies of CT, US, and MIBI scans with respect to locating remnant parathyroid glands before additional PTx were 100%, 28.6%, and 100%, respectively. A combination of CT, US, and MIBI scans is useful for initial PTx for SHPT, and CT and MIBI scans are useful imaging modalities for additional PTx procedures.

Actual role of color-doppler high-resolution neck ultrasonography in primary hyperparathyroidism: a clinical review and an observational study with a comparison of 99mTc-sestamibi parathyroid scintigraphy

PURPOSE

Primary hyperparathyroidism (PHPT) is a frequent endocrine pathology that has surgical treatment as its only decisive measure. High-Resolution Neck Ultrasonography with color-Doppler (CDHR-NUS) and 99mTechnetium-SestaMIBI Parathyroid Scintigraphy (99mTc-MIBI PS) are the two instrumental exams more commonly used in the preoperatory localization of pathologic parathyroids. The aim of this observational study was to outline-in accordance with the latest scientific literature-the precise role of CDHR-NUS in the environment of PHPT, comparing it with that of Parathyroid Scintigraphy.

METHODS

136 patients operated on for PHPT and underwent CDHR-NUS and 99mTc-MIBI PS preoperatively. The CDHR-NUS was carried out by an expert medical sonographer. The results of the two methods were compared between each other and with the results of the operative act for the evaluation of accordance and diagnostic performances.

RESULTS

PHPT is prevalently due to monoglandular pathology (SGD). The parallel use of CDHR-NUS and of 99mTc-MIBI PS does not determine a significant increase in diagnostic accuracy. The preoperative accordance evaluation between the two methods does not exclude the presence of multiglandular pathology (MGD) with certainty.

CONCLUSIONS

CDHR-NUS is an accurate as well as cost-effective method; its role as a main and eventual unique preoperative localization method in patients affected by PHPT is confirmed. In the presence of expert medical sonographers, the sequential use of the two methods is retained correct and their use in parallel is neither justified nor cost-effective. The preoperative accordance evaluation between the two methods is neither necessary nor indispensable.

Secondary and Tertiary Hyperparathyroidism: A Narrative Review

End-stage renal disease is often complicated by the occurrence of secondary and eventually tertiary hyperparathyroidism, characterized by increased parathormone, calcium, and phosphate concentrations. Related symptoms include pruritus and osteodynia, concentration difficulties, and feelings of depression may be present. In the long-term, end-stage renal disease patients with hyperparathyroidism have an increased risk of all-cause and cardiovascular mortality. Among treatment options are vitamin D supplements, phosphate binders, calcimimetics, and surgical parathyroidectomy. Determining the optimal treatment for the individual patient is challenging for nephrologists and endocrine surgeons. This review resumes the pathogenesis of hyperparathyroidism, clinical presentation, required diagnostic work-up, and discusses indications for the available treatment options for patients with secondary and tertiary hyperparathyroidism.

Low-radiation of technetium-99m-sestamibi and single-photon emission computed tomography/computed tomography to diagnose parathyroid lesions

We compared preoperative regular activity and low-activity radiology-based predictions with real surgical and pathological findings for parathyroidectomy surgery. The study retrospectively analyzed 54 consecutive cases (2009–2016) for benign tumor removal. Technetium-99m (Tc-99m)-sestamibi was used as a diagnostic radiopharmaceutical for diagnostic dual-phase parathyroid scintigraphy and single-photon emission computed tomography/computed tomography. We assessed images obtained with the radiation activity of 925 megabecquerel (MBq) and images obtained with the activity of 185 MBq. The study compared preoperative evaluation of tumor presence, multiplicity, location, and the type of pathology with actual data that were revealed during the operation and pathological investigation. The agreement between preoperative radiological prediction and actual location, number, and type of the parathyroid lesions was achieved in 98.4% (n = 61/62 lesions). The agreement between 925 MBq-based and 185-MBq based investigations was 100%. The agreement between radiological and pathological findings was 100% for both investigations. Our data suggest that the radioactivity of 185 MBq applied in the evaluation of the parathyroid glands provides results similar to the currently used 925–1110 MBq if used for diagnostic dual-phase parathyroid scintigraphy with Tc-99m-sestamibi. Such radioactivity may reduce the exposure to radiation of the patients and the staff without compromising results of the investigation.

Imaging of Parathyroid Glands in End Stage Renal Disease

Secondary hyperparathyroidism from chronic renal failure often requires a parathyroidectomy for correction. A successful parathyroidectomy often relies upon localization of all parathyroid tumors. Although most of the tumors are localized during a neck exploration, preoperative localization studies can help identify ectopic and supernumerary tumors. Three of the most common localization studies are radionuclide imaging, ultrasound, and CT scanning. Utility of these studies is strongly dependent on local institutional practice.

Combined Application of Ultrasound and CT Increased Diagnostic Value in Female Patients with Pelvic Masses

Purpose. The current study aimed to evaluate whether combined application of ultrasound and CT had increased Diagnostic Value in Female Patients with Pelvic Masses over either method alone. Patients and Methods. 240 female patients with pelvic masses were detected preoperatively with ultrasound and CT prior to surgery. The sensitivity, specificity, and accuracy of ultrasound, CT, and combined ultrasound/CT application were evaluated, respectively. Results. The sensitivity, specificity, and accuracy of ultrasound were 52.8%, 86.7%, and 68.75%, respectively. The sensitivity, specificity, and accuracy of CT were 80.3%, 90.3%, and 85%, respectively. The sensitivity, specificity, and accuracy of combined application of ultrasound and CT were 89%, 94.7%, and 91.7%. The sensitivity, specificity, and accuracy of combined application of ultrasound and CT were higher than those of either ultrasound or CT. Conclusions. The combined application of ultrasound and CT had higher Diagnostic Value in Female Patients with Pelvic Masses than either method alone.