Minimally invasive radionuclide-guided parathyroidectomy using 99mTc-sestamibi in patients with primary hyperparathyroidism: a single-institution experience

Indocyanine green fluorescence guided resection of parathyroid adenoma of the carotid sheath: a case report and review of the literature

BACKGROUND

Ectopic parathyroid tissue can pose difficulties in diagnosis, management, and resection of adenomas in patients with hyperparathyroidism. The use of multimodal pre-operative imaging is recommended due to the diverse anatomic presentation of parathyroid adenomas and the potential presence of multiple adenomas. Resection failure still can occur, however, indocyanine green (ICG) fluorescence imaging is an intraoperative tool that has potential to help address this challenge. In the case which follows we demonstrate the use of ICG fluorescence imaging to assist in successful resection of a parathyroid adenoma located within the carotid sheath.

CASE DESCRIPTION

We present the case of a 75-year-old woman with primary hyperparathyroidism due to a parathyroid adenoma localized to the left carotid sheath, posterior to the carotid artery. Careful resection was aided by ICG fluorescence guidance allowing for complete resection and immediate postoperative restoration of normal parathyroid hormone and calcium levels. The patient had no peri-operative complications and had an unremarkable post-operative course.

CONCLUSIONS

The anatomical heterogeneity of parathyroid gland adenomas within and around the carotid sheath presents a unique diagnostic and surgical scenario; however, the use of intra-operative ICG, as presented in this case, has important implications for endocrine surgeons and surgical trainees alike. This tool provides improved intra-operative identification of the parathyroid tissue allowing for safe resection, especially in cases involving critical anatomical structures.

Outcomes of Parathyroidectomy in Patients with Primary Hyperparathyroidism: A Systematic Review and Meta-analysis

BACKGROUND

Parathyroidectomy is a definitive treatment for primary hyperparathyroidism. Patients contemplating this intervention will benefit from knowledge regarding the expected outcomes and potential risks of the currently available surgical options.

PURPOSE

To appraise and summarize the available evidence regarding benefits and harms of minimally invasive parathyroidectomy (MIP) and bilateral neck exploration (BNE).

DATA SOURCES

A comprehensive search of multiple databases (MEDLINE, EMBASE, and Scopus) from each database's inception to September 2014 was performed.

STUDY SELECTION

Eligible studies evaluated patients with primary hyperparathyroidism undergoing MIP or BNE.

DATA EXTRACTION

Reviewers working independently and in duplicate extracted data and assessed the risk of bias.

DATA SYNTHESIS

We identified 82 observational studies and 6 randomized trials at moderate risk of bias. Most of them reported outcomes after MIP (n = 71). Using random-effects models to pool results across studies, the cure rate was 98 % (95 % CI 97-98 %, I (2) = 10 %) with BNE and 97 % (95 % CI 96-98 %, I (2) = 86 %) with MIP. Hypocalcemia occurred in 14 % (95 % CI 10-17 % I (2) = 93 %) of the BNE cases and in 2.3 % (95 % CI 1.6-3.1 %, I (2) = 87 %) with MIP (P < 0.001). There was a statistically significant lower risk of laryngeal nerve injury with MIP (0.3 %) than with BNE (0.9 %), but similar risk of infection (0.5 vs. 0.5 %) and mortality (0.1 vs. 0.5 %).

LIMITATIONS

The available evidence, mostly observational, is at moderate risk of bias, and limited by indirect comparisons and inconsistency for some outcomes (cure rate, hypocalcemia).

CONCLUSION

MIP and BNE are both effective surgical techniques for the treatment of primary hyperparathyroidism. The safety profile of MIP appears superior to BNE (lower rate of hypocalcemia and recurrent laryngeal nerve injury).

Could the eZ-SCOPE AN gamma camera replace intraoperative measurement of iPTH for PHPT?

Intraoperative intact parathyroid hormone (iPTH) measurements have been proposed as an effective assay in surgery for primary hyperparathyroidism (PHPT). We have demonstrated the efficiency of the use of a hand-held gamma camera, eZ-SCOPE AN, with technetium-99m sestamibi (Tc-MIBI) scintigraphy for navigation surgery for PHPT. The aim of this preliminary study was to assess the possibility that the eZ-SCOPE AN can replace the measurement of intraoperative iPTH in surgery for PHPT. Sixteen consecutive patients with documented primary hyperparathyroidism underwent surgery using this compact camera. iPTH was routinely measured preoperatively and 10 minutes after the complete removal of adenoma. All patients had a well-defined parathyroid lesion identified on preoperative Tc-MIBI. The eZ-SCOPE revealed hyperfunctioning parathyroid glands in all cases. iPTH levels were decreased in all cases after the removal of adenomas. Our results suggest that this gamma camera is useful for confirming complete resection of endocrinologically active tissue in surgery for PHPT. In selective patients with scan-positive cases identified by preoperative Tc-MIBI, the eZ-SCOPE may replace the intraoperative iPTH assay in surgery for PHPT.

Use of a Handheld, Semiconductor (Cadmium Zinc Telluride)-Based Gamma Camera in Navigation Surgery for Primary Hyperparathyroidism

The recent development of gamma-ray probes makes it possible to perform radioguided surgery for primary hyperparathyroidism (PHPT). There have only been a few reports, however, regarding the use of a handheld gamma camera to detect parathyroid adenoma intraoperatively. The aim of this preliminary study was to assess the efficiency of a semiconductor gamma camera (eZ-SCOPE AN) in navigation surgery for PHPT. The eZ-SCOPE is designed to be used as a handheld, regional diagnostic imaging device. Eleven consecutive patients with documented primary hyperparathyroidism underwent surgery using this compact camera. Scintigraphy images of the neck by eZ-SCOPE were acquired: 1) before skin incision; 2) after adenoma location; 3) after adenoma excision; and 4) ex vivo imaging of the specimen. In scan-positive cases by preoperative Tc-MIBI, the eZ-SCOPE revealed parathyroid adenoma in all cases (100%), whereas ultrasound and CT showed a single adenoma in 63.6 and 72.7 per cent of cases, respectively. Navigation surgery for PHPT using the eZ-SCOPE permitted intraoperative identification and removal of parathyroid adenoma in all cases. Scintigraphy images of the neck by eZ-SCOPE also revealed a single adenoma even before skin incision. Our results suggest that Tc-MIBI scintigraphy with the eZ-SCOPE is useful for navigation surgery for PHPT. The eZ-SCOPE is useful for skin marking and could be easily applied for minimally invasive radioguided parathyroidectomy in scan-positive cases.