title: Diagnostic localization of ectopic parathyroid lesions: developmental consideration.
abstract: Parathyroid glands arise from the third and fourth pharyngeal pouches. Parathyroid lesions sometimes develop ectopically. The aim of this article is to illustrate the knowledge of pharyngeal apparatus development to assist with diagnostic localization of ectopic parathyroid lesions. We retrospectively reviewed charts of 23 patients who received a diagnosis of ectopic parathyroid lesions. The ectopic lesions were widely distributed; cranially lesions were located on the carotid bifurcation, caudally in the right paraaortic region, ventrally on the surface of the sternohyoid muscle, and dorsally in the paraesophageal region. In most cases, parathyroid tissues were associated with structures related to the third or fourth pharyngeal pouches that traveled to regions where the ectopic lesions ultimately developed. In a few cases, lesions were not associated with these pouches and might have developed from parathyroid tissue that migrated due to an anomalous pathway of parathyroid travel. When patients present without entopic lesions, the presence of ectopic lesions should be evaluated based on an understanding of the developmental mechanisms of parathyroid glands and the frequency with which ectopic lesions have been found in specific locations. Systematic diagnosis can minimize the frequency with which ectopic lesions are missed during clinical care and maximize their accurate localization.
authors.affiliation: Department of Diagnostic Radiology, Toranomon Hospital, 2-2-2 Toranomon, Minato-ku, Tokyo, 105-8470, Japan. okudai-tora@umin.ac.jp
authors.forename: Itsuko
authors.initials: I
authors.lastname: Okuda
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Nakajima
authors.forename: Daishu
authors.initials: D
authors.lastname: Miura
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Maruno
authors.forename: Tadasu
authors.initials: T
authors.lastname: Kohno
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Hirata
mesh_terms: D000236:Adenoma / Q000000981:diagnostic imaging* / Q000473:pathology; D000328:Adult; D000368:Aged; D003287:Contrast Media; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000000981:diagnostic imaging / Q000473:pathology; D010282:Parathyroid Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D017256:Technetium Tc 99m Sestamibi; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D003287:Contrast Media; D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi