The prevalence and anatomy of parathyroid glands: a meta-analysis with implications for parathyroid surgery

Abstract

Purpose The anatomy of parathyroid glands (PTG) is highly variable in the population. The aim of this study was to conduct a systematic analysis on the prevalence and location of PTG in healthy and hyperparathyroidism (HPT) patients. Methods An extensive search of the major electronic databases was conducted to identify all studies that reported relevant data on the number of PTG per patient and location of PTG. The data was extracted from the eligible studies and pooled into a meta-analysis. Results The overall analysis of 26 studies ( n = 7005 patients; n = 23,519 PTG) on the number of PTG showed that 81.4% (95% CI 65.4–85.8) of patients have four PTG. A total of 15.9% of PTG are present in ectopic locations, with 11.6% (95% CI 5.1–19.1) in the neck and 4.3% (95% CI 0.7–9.9) in mediastinum. The subgroup analysis of ectopic PTG showed that 51.7% of ectopic PTG in the neck are localized in retroesophageal/paraesophageal space or in the thyroid gland. No significant differences were observed between the healthy and HPT patients and cadaveric and intraoperative studies. Conclusions Knowledge regarding the prevalence, location, and anatomy of PTG is essential for surgeons planning for and carrying out parathyroidectomies, as any unidentified PTG, either supernumerary or in ectopic location, can result in unsuccessful treatment and need for reoperation. Electronic supplementary material The online version of this article (10.1007/s00423-019-01751-8) contains supplementary material, which is available to authorized users.

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

“…In the majority of cases, four PGs are present, nevertheless, there are individuals either with a less or excessive number of PGs (even up to twelve glands) [24]. The results of a recent meta-analysis, which involved 26 studies and 7005 patients, showed that 81.4% of patients had four PGs [25]. Regarding the geographical location, the results of the studies in North and South America revealed a smaller number of patients with four PGs compared to Europe.…”

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

“…Surgical failure is mainly due to the di culty of resecting all parathyroid glands, especially because of the existence of supernumerary (more than 4) and ectopic parathyroid glands. The incidence of ectopic and supernumerary glands in patients with end-stage renal disease has been reported to be 17.5-39.3% and 6.3-37%, respectively [7][8][9]. Therefore, preoperative imaging and accurate localization are critical to a successful operation.…”

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

“…Surgical failure is mainly due to the difficulty to resect all parathyroid glands especially because of the existence of supernumerary (more than 4) and ectopic parathyroid glands. It is reported that the incidences of ectopic and supernumerary glands reported in patients with end-stage kidney disease are 17.5-39.3% and 6.3-37%, respectively [7][8][9].Therefore, preoperative imaging and accurate localization is critical to a successful operation.…”