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The parathyroid glands are endocrine glands located in close association with the thyroid gland in most patients. There are normally four individual parathyroids, though supernumerary parathyroids have been found in up to 13% of autopsies[1].  There are two glands located superiorly called the superior parathyroid gland and a pair that are located inferiorly- referred to as the inferior parathyroid glands.  Ectopy of one or more parathyroids is relatively common, with a meta-analysis revealing up to 16% of glands may be in an ectopic location including the mediastinum, retro-esophageal area, or other aberrant locations in the lateral neck[1]. Superior parathyroid glands: These glands derive from the fourth pharyngeal pouch.  They are classically located near the posterolateral aspect of the superior pole of the thyroid, 1cm superior to the junction of the recurrent laryngeal nerve (RLN), and the inferior thyroid artery. They classically lie deep to the plane of the recurrent laryngeal nerve. Inferior parathyroid glands: These glands derive from the third pharyngeal pouch. These glands are classically located near the inferior poles of the thyroid glands, within 1-2 cm of the insertion of the inferior thyroid artery into the inferior pole of the thyroid. They classically lie superficial to the plane of the RLN. Their location is much more variable than the superior parathyroids, and can be intra-thyroidal or within the thymus or other mediastinal structures, and can even be found along the aortic arch.[2]