Parathyroid ultrasonography: the evolving role of the radiologist

Dynamic 4 dimensional contrast enhanced MRI for localization in primary hyperparathyroidism

PURPOSE

It can be challenging to localize the lesions in certain cases of primary hyperparathyroidism. Recently, it has been proposed that assessing the localization of parathyroid lesions with dynamic images enhances the diagnostic power of standard MRI (magnetic resonance imaging) due to the hypervascular structure of these lesions. In this study, we aimed to evaluate the success of four-dimensional dynamic perfusion MRI (4D MRI) in localizing parathyroid lesions.

METHODS

Thirty patients who underwent 4-dimensional dynamic MRI diagnosed with primary hyperparathyroidism and indications for surgery, whose USG (ultrasonography) and/or Tc 99m sestamibi SPECT scan were negative or discordant, were included. The sensitivity and positive predictive values (PPV) were calculated for each imaging modality.

RESULTS

Of the 30 patients, 29 had parathyroid adenoma, and one had parathyroid hyperplasia in histopathologic examination. 4D MRI accurately identified the location of parathyroid lesions in 25 of 30 patients (sensitivity 83.3%, PPV 96.1%), whereas USG successfully identified the lesion location in 21 patients (sensitivity 70%, PPV 91.3%) and Tc 99m sestamibi SPECT scan in 17 patients (sensitivity 56.7%, PPV 94.4%). The sensitivity of the combination of three imaging modalities was found to be 96.7%.

CONCLUSION

4D MRI can be utilized as a complementary imaging modality to localize parathyroid lesions, offering the advantage of no ionizing radiation, especially when USG and/or Tc 99m sestamibi SPECT scans cannot reliably identify them.

Addressing the challenges of missed parathyroid glands in ultrasonography for secondary hyperparathyroidism: a retrospective observational study

Purpose

Preoperative localization plays an important role in secondary hyperparathyroidism (SHPT) surgery. The advantages of neck ultrasound (US) include high availability and low cost. However, the reported sensitivity of US is 54%-76%, and the reason for missed parathyroid glands (PGs) on US has been rarely addressed.

Methods

Fifty-four patients who were diagnosed with renal SHPT from September 2020 to March 2022 were included in this retrospective study. Preoperative localization included surgeon-oriented US and technetium 99m-sestamibi single-photon emission CT (SPECT)/CT.

Results

A total of 212 PGs were pathologically confirmed, resulting in a success rate of 96.2% (52 of 54). Using echo, 193 PGs (91.0%) were accurately localized, while 19 glands (9.0%) were not identified, including those in ectopic positions (n = 12, at thymus or intrathyroid or others), of small size (<1 cm, n = 6), or overlapping with an ipsilateral PG (n = 1). US accurately detected 4 PGs in 36 (66.7%) patients, while SPECT/CT localized 4 glands in 19 patients (35.2%). Although the number of US-detectable PGs was not associated with success rate, it showed a significant negative correlation with surgical time (rs = -0.459, P = 0.002).

Conclusion

US detected 4 glands in 66% of SHPT patients with a sensitivity of 90% for localization. Ectopic position and small size were the most common reasons for the failure to detect PG on US. Complete preoperative echo localization might shorten operating time.

EVALUATION AND MANAGEMENT OF PARATHYROID INCIDENTALOMAS DETECTED BY ROUTINE NECK ULTRASONOGRAPHY WITH A MULTIDISCIPLINARY CLINICAL APPROACH

Contex

Detection of parathyroid incidentalomas (PTIs) by ultrasonography (US) generally depends on clinical experience and it can be usually confused with perithyroidal lymph nodes.

Objective

We aimed to evaluate the role of US for the detection of PTIs and define clinicopathologic features of PTIs detected during routine neck US.

Design

In this retrospective study, we studied PTIs in a multidisciplinary clinical approach of nuclear medicine and general surgery clinics.

Subjects and Methods

US indications and reports of 41275 were reviewed retrospectively. Of these patients, PTI was suspected in 66 (0.16%) patients. Those with a pathology-confirmed diagnosis after surgery formed Group PCD and those without a pathology-confirmed diagnosis and operation Group NPCD. These groups were compared statistically according to demographic data, laboratory tests, imaging results and postoperative findings.

Results

The diagnosis of PTI was confirmed pathologically in 31 operated patients. Other pathologies rather than PTI on US were multinodular goiter, thyroiditis, thyroid nodule and perithyroidal lymph node. PTH and calcium levels were significantly higher in PCD Group;anti-TPO and anti-TG levels were significantly higher in NPCD Group.

Conclusions

Lesions suspected of PTI on US should be followed-up with further evaluation by laboratory tests and imaging methods and a multidisciplinary working environment should be established.

What is this bump in my neck? Ultrasonographic evaluation of pediatric neck masses

Neck masses are common in pediatric patients, with benign etiologies such as congenital or inflammatory lesions accounting most of these masses. Anatomic location (most important), clinical history, and the appearance in ultrasonography (US) are helpful clues to narrow down differential diagnosis. Because of widespread availability, lack of ionizing radiation, and no need for sedation or contrast administration, US is the preferred initial modality for the evaluation. Further evaluation with cross-sectional imagings is needed for more extensive lesions with trans-spatial extension or suspicion of intrathoracic or retropharyngeal extension. This review will focus on US appearance and clinical presentation of masses of the neck in children, to enable radiologist to arrive at a reasonable differential diagnosis. We also briefly discuss more complex pathologies that need to be evaluated with cross-sectional modalities such as CT scan and magnetic resonance imaging.

Diagnosis of parathyroid incidentaloma detected on thyroid ultrasonography: the role of fine-needle aspiration cytology and washout parathyroid hormone measurements

PURPOSE

The aim of this study was to assess the diagnostic role of fine-needle aspiration cytology (FNAC) and analyze factors associated with false-negative FNAC results in patients with parathyroid incidentaloma who were referred for ultrasonography (US)-guided fine-needle aspiration (FNA) of thyroid nodules.

METHODS

In this study, 121 patients with suspected parathyroid lesions were enrolled. The patients underwent US-guided FNAC with measurements of washout parathyroid hormone (PTH) between January 2015 and May 2020. The diagnostic performance of FNAC for the diagnosis of parathyroid lesions was assessed using surgical results and elevated washout PTH as a reference standard. The clinical and radiologic features associated with false-negative results on FNAC for the diagnosis of parathyroid lesions were evaluated.

RESULTS

Among the 121 nodules assessed, 38 were parathyroid lesions (31.4%), and 83 were non-parathyroid lesions (68.6%). The diagnostic performance of FNAC for parathyroid incidentaloma showed a sensitivity of 31.6% (12/38), specificity of 100% (83/83), positive predictive values of 100% (12/12), negative predictive values of 76.1% (83/109), and accuracy of 78.5% (95/121). The FNAC results of non-parathyroid lesions included thyroid nodules, lymph nodes, neurogenic tumors, and fat tissue. True-positive results on FNAC were significantly associated with performing FNA twice (58.3% vs. 23.1%, P=0.043).

CONCLUSION

Considering the low sensitivity of FNAC, measuring washout PTH in addition to FNAC may help accurately diagnose parathyroid incidentaloma on thyroid US. Further, the falsenegative rate for FNAC can be reduced by obtaining two or more FNA samples.

The added value of non-contrast 3-Tesla MRI for the pre-operative localization of hyperparathyroidism

OBJECTIVE

We investigated the efficacy of non-contrast 3-Tesla MR imaging added to the combination of sestamibi with^99mTc (MIBI) scintigraphy and Ultrasonography (US) for the pre-operative localization of Primary Hyperparathyroidism (PHPT) lesions.

METHODS

A total of 34 parathyroid glands, including nine normal glands, were examined with MIBI, US, and non-contrast 3-Tesla MRI. MRI was performed with the acquisition of T1- and T2-weighted images and fat-suppressed T2-weighted images. We calculated the sensitivities of MIBI, US, and the 'additional' MRI, with knowledge of the former two modalities' results.

RESULTS

For the diagnosis of PHPT lesions, the sensitivity values of MIBI, US, and additional MRI were 88.0% (22/25), 84.0% (21/25), and 92.0% (23/25), respectively. Normal glands were not visualized with any modality (0/9). One lesion was detected neither with US nor MRI, but only with MIBI, with the limitation that MIBI represented no more than laterality. The two glands not identified in MRI were 4 mm and 6 mm in their size, which are within the range of normal gland's size. Two lesions were not detected with US or MIBI but were visualized with the additional MRI, which indicated that the MRI contributed an 8.0% (2/25) improvement of sensitivity, compared from that of US. Fat-suppressed T2-weighted images were useful in the identification of parathyroid lesions, as these images helped to differentiate between the lesion and the adjacent tissue.

CONCLUSION

Additional non-contrast 3-Tesla MRI was a useful adjunctive tool for localization of PHPT, which improved the sensitivity of the pre-operative localization of PHPT lesions. Fat-suppressed T2-weighted images contributed to their identification.

LEVEL VI

Evidence from a single descriptive or qualitative study.

Relative Perfusion Differences between Parathyroid Adenomas and the Thyroid on Multiphase 4DCT

A multiphase 4DCT technique can be useful for the detection of parathyroid adenomas. Up to 16 different phases can be obtained without significant increase of exposure dose using wide beam axial scanning. This technique also allows for the calculation of perfusion parameters in suspected lesions. We present data on 19 patients with histologically proven parathyroid adenomas. We find a strong correlation between 2 perfusion parameters when comparing parathyroid adenomas and thyroid tissue: parathyroid adenomas show a 55% increase in blood flow (BF) (p < 0.001) and a 50% increase in blood volume (BV) (p < 0.001) as compared to normal thyroid tissue. The analysis of the ROC curve for the different perfusion parameters demonstrates a significantly high area under the curve for BF and BV, confirming these two perfusion parameters to be a possible discriminating tool to discern between parathyroid adenomas and thyroid tissue. These findings can help to discern parathyroid from thyroid tissue and may aid in the detection of parathyroid adenomas.

Contrast-Enhanced Ultrasound Qualitative and Quantitative Characteristics of Parathyroid Gland Lesions

Background and Objectives: preoperative differentiation of enlarged parathyroid glands may be challenging in conventional B-mode ultrasound. The aim of our study was to analyse qualitative and quantitative characteristics of parathyroid gland lesions, using multiparametric ultrasound protocol—B-mode, Colour Doppler (CD), and contrast-enhanced ultrasound (CEUS)—and to evaluate correlation with morphology in patients with hyperparathyroidism (HPT). Materials and Methods: consecutive 75 patients with 88 parathyroid lesions and biochemically confirmed HPT prior to parathyroidectomy were enrolled in the prospective study. B-mode ultrasound, CD, and CEUS were performed with the subsequent qualitative and quantitative evaluation of acquired data. We used 1 mL or 2 mL of intravenous ultrasound contrast agent during the CEUS examination. Correlation with post-surgical morphology was evaluated. Results: seventy parathyroid adenomas were hypoechoic and well contoured with increased central echogenicity (44.3%), peripheral-central vascularization (47%), and polar feeding vessel (100%). Twelve hyperplasias presented with similar ultrasound appearance and were smaller in volume (p = 0.036). Hyperplasias had a tendency for homogenous, marked intense enhancement vs. peripherally enhanced adenomas with central wash-out in CEUS after quantitative analysis. No significant difference was observed in contrasting dynamics, regardless of contrast media volume use (1 mL vs. 2 mL). We achieved 90.9% sensitivity and 72.7% specificity, 93% positive predictive value (PPV), 87.3% negative predictive value (NPV), and 87.3% accuracy in the differentiation of parathyroid lesions prior to post-processing. In a quantitative lesion analysis, our sensitivity increased up to 98%, specificity 80%, PPV 98%, and NPV 80% with an accuracy of 96.4%. Conclusions: CEUS of parathyroid lesions shows potential in the differentiation of adenoma from hyperplasia, regardless of the amount of contrast media injected. The quantitative analysis improved the sensitivity and specificity of differentiation between parathyroid lesions. Hyperplasia was characterized by homogeneous enhancement, fast uptake, and homogeneous wash-out appearance; adenoma—by peripheral uptake, central wash-out, and reduced hemodynamics. The use of CEUS quantification methods are advised to improve the ultrasound diagnostic role in suspected parathyroid lesions.

Multiple endocrine neoplasia 1: a broad overview

This review article discusses the diagnoses and treatment of patients with multiple endocrine neoplasia type 1 (MEN 1). The most common tumors associated with MEN 1 are located in the pancreas, pituitary, and parathyroid glands. Less common tumors include neuroendocrine tumors of the lung and thymus, adrenal tumors, and cutaneous lesions. This article describes the diagnosis, clinical manifestations, treatment, and surveillance of tumors associated with patients who are diagnosed with MEN 1.

PRIMARY HYPERPARATHYROIDISM DETECTED BY PARATHYROID INCIDENTALOMA: CLINICAL FEATURES, WORK-UP AND MANAGEMENT

CONTEXT

With the widespread use of neck ultrasound, parathyroid incidentaloma (PI) emerges as an additional opportunity for incidental detection of primary hyperparathyroidism (PHPT).

OBJECTIVE AND DESIGN

This study aimed to investigate PHPT cases detected by PI and to compare them with other PHPT patients. A retrospective analysis of newly diagnosed PHPT patients between 2014 and 2020 was conducted in our hospital.

SUBJECTS AND METHODS

The cohort of 124 subjects was divided in two groups: 22 (17.7%) PHPT patients detected by PI (PI PHPT group) and the rest of 102 PHPT patients (non-PI PHPT group). Overall, 21 PIs were discovered on ultrasound and one was found during thyroid surgery. Clinical features, work-up and management of two study groups were compared.

RESULTS

The PI PHPT group had lower ionized calcium at diagnosis (p=0.034), lower peak serum calcium during follow-up (p<0.01), less fractures (p=0.022) and was less likely to meet the international criteria for parathyroidectomy (p<0.01). Positive sestamibi scan (p=0.022) and confirmed concordant localization in at least two different parathyroid imaging techniques (p=0.033) were more likely in the PI PHPT group. The frequency of surgical management did not differ between groups.

CONCLUSIONS

PHPT detected by PI is clinically relevant and mostly comparable to PHPT in other patients with some features that correspond more often to a mild disease. Higher rate of positive preoperative localization in PHPT detected by PI might encourage parathyroidectomy even without the international criteria met.

Usefulness of the Wisconsin and CaPTHUS indices for predicting multiglandular disease in patients with primary hyperparathyroidism in a southern European population

Background

Focused parathyroidectomy is a safe technique for the treatment of primary hyperparathyroidism. The CaPTHUS score and the Wisconsin index are preoperative diagnostic tools designed to distinguish between single- and multigland disease. The aim of the study is to evaluate the usefulness of these models for predicting multiglandular disease in a European population.

Methods

Retrospective review of a database of patients operated upon for primary hyperparathyroidism at a referral center. The sensitivity, specificity, positive and negative predictive values, and reliability of both scores for the prediction of multiglandular disease, were calculated. Receiver operating characteristic (ROC) curves were constructed to assess the sensitivity and specificity of CaPTHUS score and Wisconsin Index for predicting single-gland disease. A level of P<0.05 was accepted as significant.

Results

Two hundred and eighty-one patients who underwent successful surgery from January 2001 to December 2018 were included. Single-gland disease was detected in 92.5%, and 73.7% had a CaPTHUS score of ≥3. The sensitivity, specificity, positive and negative predictive values of this model for predicting single-gland disease with a score of ≥3 were 76.9%, 66.7%, 96.6%, and 18.9% respectively. The area under the curve value of the CaPTHUS score for predicting single-gland disease was 0.74. A Wisconsin Index >2,000 and an excised gland weight above one gram presented a positive predictive value for single-gland disease of 92.5%.

Conclusions

Despite the good performance of both scales, the established cut-off points did not definitively rule out parathyroid multiglandular disease in our population. In cases with a minimal suspicion of this condition, additional intraoperative techniques must be used, or bilateral neck explorations should be performed.

Neck Procedures: Thyroid and Parathyroid

Fine-needle aspiration (FNA) and core biopsy of masses in the neck predominantly include samples from thyroid nodules, parathyroids and lymph nodes. The diagnostic rate of a thyroid nodule FNA improves up to 6 passes and then does not significantly change. Thyroid FNA can be performed on patients who are anticoagulated. Appropriate transducer selection is essential for visualization of the needle. Lymph node biopsies can be additionally sampled for thyroglobulin assay to improve sensitivity for detection of recurrent carcinoma. Parathyroid FNA usually involves additional estimation of parathyroid hormone concentration in needle washouts. Biopsies of the neck are simple procedures with minimal complications.

Parathyroid Cyst: A Case Report of an Uncommon Diagnosis of a Cervical Mass

Parathyroid cysts (PCs) are uncommon entities in clinical practice. The lack of pathognomonic clinical presentation and radiological features of PCs makes preoperative diagnosis unlikely, therefore, most cases are diagnosed intraoperatively or postoperatively at the pathological analysis of the surgical specimen. Treatment of nonfunctional PCs remains controversial and includes fine-needle aspiration, injection of sclerosant, or surgical excision. However, surgical resection still the optimal treatment for functional and larger nonfunctional PCs. We report a case of a 60-year-old female presenting with asymptomatic left-sided cervical swelling diagnosed postoperatively as a nonfunctional PC.

Ultrasonographic and anatomical examination of normal thyroid and internal parathyroid glands in goats

Ultrasonographic examination of the normal thyroid and parathyroid glands has been described for humans and many animal species. However, similar reports for goats are still missing. The aim of the study was to present ultrasound features of the normal thyroid and internal parathyroid glands in goats with the determination of their dimensions and volume, followed by a comparison of the results to the gross examination. Seventy-two goats were used in the study. The echostructure and echogenicity of the thyroid and parathyroid glands were assessed. The length, width and height of the thyroid and the length and width of the parathyroid glands were measured. The thyroid volume was calculated using the ellipsoid formula, basing on the ultrasonographic dimensions. Size and volume of the dissected thyroid glands were established grossly, followed by a histological examination. In order to accurately describe the anatomy of the thyroid, new anatomical terminology characterizing this gland was proposed. The mean dimensions of the thyroid lobes were 30.2 x 10.5 x 6.3 mm. There were no statistically significant differences between the right and left lobe. Parathyroid glands measured an average of 3.6 x 2.4 mm. The percentage Root Mean Square Error between the results of ultrasonographic and gross examination was 16.73%, 20.65% and 17.01% for thyroid length, width and height, respectively, and 46.30% for volume. In order to obtain more precise calculation of the thyroid volume, a modified correction factor for the ellipsoid formula was introduced. For the first time, the normal ultrasonographic characteristics and dimensions of the caprine thyroid and internal parathyroid glands were presented. The results may serve as a radiological reference and be the basis for further research.

OCCULT PRIMARY HYPERPARATHYROIDISM: A CASE REPORT AND REVIEW OF PARATHYROID ULTRASONOGRAPHY

Objective

To discuss the diagnosis and management of occult primary hyperparathyroidism.

Methods

We present the biochemical and radiologic evaluation, treatment, and outcome of a woman with occult primary hyperparathyroidism which presented as an unusual neck mass on ultrasound. We also present a relevant literature review.

Results

A 52-year-old female presented with Hashimoto thyroiditis and a 1.2-cm, hypoechoic oval nodule in the left upper lateral portion of the thyroid. She returned a decade later with a 2.2-cm, hypervascular mass on ultrasound. Parathyroid hormone was mildly elevated at 90 pg/mL (reference range is 15 to 65 pg/mL), but she had persistently normal levels of total serum calcium at 9.9 mg/dL (reference range is 8.7 to 10.3 mg/dL), phosphorus at 3.5 mg/dL (reference range is 2.1 to 4.5 mg/dL), and albumin at 4.4 g/dL (reference range is 3.6 to 4.8 g/dL). She had elevated ionized calcium of 5.9 mg/dL (reference range is 4.5 to 5.6 mg/dL). Computed tomography with contrast of the neck revealed an enhancing oval lesion abutting the superior pole of the left thyroid with attenuation characteristics similar though slightly different from the thyroid. 99mTc-Sestamibi scan showed increased uptake posterior to the superior aspect of the left thyroid. Bone densitometry showed osteoporosis of the left distal radius and osteopenia of the left femoral neck. Minimally invasive radio-guided parathyroidectomy was performed with normalization of parathyroid hormone. Pathology confirmed a 1.715-g parathyroid adenoma.

Conclusion

Despite normal total calcium levels, clinically significant primary hyperparathyroidism may present as a large adenoma which could appear as a hypervascular neck mass on ultrasound. A high index of suspicion based on ultrasound features and measurement of ionized calcium may be helpful in diagnosing occult, but clinically relevant primary hyperparathyroidism.

[Imaging of medullary thyroid carcinoma]

BACKGROUND

About 10% of thyroid cancers are medullary thyroid carcinoma (MTC) and can occur sporadically, familially and in the context of type II multiple endocrine neoplasia (MEN). Imaging plays a pivotal role in screening family members and in diagnosis.

DIAGNOSTIC METHODS

Diagnosis is based on ultrasound (US), thyroid scintigraphy, serum calcitonin and carcinoembryonic antigen (CEA) as well as fine needle biopsy. High-resolution US is the most important imaging method for locoregional staging, combined with computed tomography (CT) of the mediastinum. Positron emission tomography (PET-CT) using 18-F-DOPA is particularly suited for suspected occult metastases in case of rising tumor markers in serum.

FINDINGS AND COURSE OF DISEASE

Diagnosis is made based on cytologic findings in a hypoechoic, cold thyroid nodule, combined with an elevation of serum calcitonin and CEA. US is the most important imaging modality during routine follow-up. CT is indicated for suspected mediastinal, lung, or liver metastases. CT should be replaced by MRI as early as possible to prevent significant cumulative radiation doses over time.

RECENT CLINICAL DEVELOPMENTS

Although MTC is curable by surgery only, owing to its radio- and chemoresistance, the disease will often progress only slowly, and even patients with metastases will frequently survive 10 years or longer. For more aggressive variants and late symptomatic stages, targeted drugs that have the potential to indicate stabilization or even a partial remission of the disease are under clinical investigation or already approved.

Study of the Ultrasound Appearance of the Normal Parathyroid Using an Intraoperative Procedure

OBJECTIVES

This study was designed to confirm the echogenicity of normal parathyroid glands using intraoperative ultrasound (US).

METHODS

Between October 2015 and January 2016, normal parathyroid glands were examined with an intraoperative US transducer during thyroidectomy procedures in 13 patients with thyroid disease. According to the findings from intraoperative US, routine percutaneous US of normal parathyroid glands was performed in a group of adults. On the basis of previous information on normal parathyroid echogenicity, a series of parathyroid diseases that were proved by surgery and histopathologic analyses were retrospectively reviewed. The presence of residual normal parathyroid in the lesion on US imaging, which was defined as the residual parathyroid sign in this study, was reviewed and correlated with histopathologic results.

RESULTS

In the intraoperative US group, 23 parathyroid glands were scanned intraoperatively, and 21 (91.3%) were hyperechoic, homogeneous in texture, and oval. In the routine percutaneous US group, 106 parathyroid glands were found in total, and 96 (90.5%) of the glands had hyperechoic and homogeneous echogenicity, with 75 (70.8%) being oval. In the review of parathyroid diseases, 33 parathyroid glands in 30 cases were reviewed, with a positive residual parathyroid sign in 7 (21.2%) parathyroid glands, presenting with a hyperechoic rim in the margin, and 4 of them (12.1%) were confirmed by histopathologic results.

CONCLUSIONS

The normal parathyroid had hyperechoic echogenicity on both intraoperative and percutaneous US imaging. Residual tissue of parathyroid glands can also be observed in some parathyroid abnormalities with an echogenic appearance on US imaging and confirmed by histopathologic results.

Parathyroid cysts: experience of a rare phenomenon at a single institution

Background

Parathyroid cysts are relatively uncommon lesions and are often misdiagnosed. We evaluate our experience in the diagnosis of and therapy to correct parathyroid cystic lesions.

Methods

We retrospectively reviewed a series of 32 patients with parathyroid cysts who were admitted to our department between July 2011 and November 2016. Clinical pathological features of the patients, including age, gender, location, size, ultrasonography, histopathology, surgery, and follow-up, were analyzed.

Results

There were 22 female and 10 male participants with a median age of 46.7 years old (27–76 years old). Only two cysts were found in the superior mediastinum. The rest were located under the lower pole of the thyroid. All of the patients underwent ultrasonography scans and serum parathyroid hormone (PTH) assays. Three patients had elevated serum PTH levels, and they were further scanned with Tc99m sestamibi as functional cysts. In 29 cases of nonfunctional cysts, 3 cases were preoperatively diagnosed by cystic aspiration with PTH detection. The rest were diagnosed by postoperative immunopathology. All of the patients underwent cystectomy, and 24 patients also underwent thyroidectomy. There was a significant difference in cyst diameter size between the cystectomy alone and cystectomy with thyroidectomy groups (4.0 ± 2.0 vs 1.5 ± 1.0 cm; p < 0.05). No participant experienced recurrence during the median 36 months of follow-up.

Conclusions

Cystic lesions located under the lower pole of the thyroid gland should be considered to have originated at the parathyroid gland. Cystic aspiration with PTH detection or postoperative immunopathology can lead to a definitive diagnosis. Cystectomy is still a commonly used and effective treatment.

Validation of selective use of intraoperative PTH monitoring in parathyroidectomy

BACKGROUND

The objective of this study was to validate our approach of treating primary hyperparathyroidism using sestamibi scan directed parathyroidectomy, without routine use of intraoperative parathyroid hormone measurements (ioPTH).

METHODS

We prospectively established a protocol limiting the use of ioPTH to patients with negative or equivocal sestamibi scans, and those who had risk factors for multi-gland disease. We then performed a retrospective review to determine our disease control rate.

RESULTS

128 patients underwent sestamibi-guided parathyroidectomy without (111/128 = 87%) or with (17/128 = 13%) ioPTH. The overall disease control (eucalcemia) rate was 95%. 3/111 (3%) of patients who had surgery without ioPTH measurements required re-exploration.

CONCLUSIONS

Selective use of ioPTH is an effective strategy. ioPTH is best reserved for patients who have non-localizing preoperative imaging, are at risk for multi-gland disease, or require revision surgery.