Anthropological Variations in the Anatomy of the Human Thyroid Arteries

Abstract

Knowledge of anatomic variability of the superior (STA), inferior (ITA), and lowest accessory (IMA) thyroid arteries may be helpful in certain clinical conditions. However, details of this variability have not been thoroughly described. Specifically, whether the presence and site of origin of STA, ITA, and IMA are influenced by the anthropological group, to what extent their origin is symmetric or asymmetric, and the role played by this variability in visualizing each thyroid artery by nonselective thyroid angiography is not known. To clarify this we conducted a meta-analytical study on Caucasian and Asian subjects, the latter including only Japanese and Koreans. In Caucasians and Asians the presence of superior vessels compared to inferior vessels was more frequent and the probability of symmetric or asymmetric arterial origin for STA were equivalent. However, better recognition of inferior rather than superior vessels was achieved by nonselective angiography in Caucasians. Finally, different frequencies of presence and site of origin for each artery were identified in Caucasians compared to Asians. Our results suggest that the higher frequency of IMA in Asians than in Caucasians should result in a search for an IMA-dependent feeding artery of inferior parathyroid adenomas, primarily the mediastinal ones, especially in Asians both by imaging and transcatheter ablative approaches. In addition, we have found that a small percentage of Caucasian subjects lack an STA on the left side. Therefore, anatomic arterial compatibility should be carefully evaluated in the preoperative stage of laryngeal transplantation maintaining in situ the donor's thyroid by terminal anastomoses between donor and recipient STAs. Finally, the lack of any individual thyroid artery in either Caucasians or Asians might influence the distribution of autonomic supply that runs with thyroid vessels to the thyroid parenchyma. This appears functionally relevant in cases of traumatic or surgical lesions of the cervical sympathetic chain involving thyroid nerves. In fact, a restricted local autonomic control of thyroid activity might be related to individual rami of thyroid nerves.

Irrigación de la Glándula Tiroides en una Muestra de Población Colombiana

“…Entre los factores que explicarían dichas variaciones, diversos autores las han relacionado con el grupo étnico de las personas (Toni et al, 2003(Toni et al, , 2004(Toni et al, , 2005; sin embargo, en las descripciones de la variable "grupo étnico" no utilizan criterios claros, que la definan más allá de la procedencia del individuo.…”

Autonomous Adenomas Caused by Somatic Mutations of the Thyroid-Stimulating Hormone Receptor in Children

“…Table 2 shows that the degree of hyperthyroidism of our 4-year-old patient was much more severe, and possibly more protracted, than that of the 8-year-old in spite of both patients having the same somatic mutation in TSHR and both autonomous adenomas having the same weight relative to body size. This may result from the fact that the autonomous adenoma in patient 1 was in the right thyroid lobe, which is more richly vascularized than the left [30]. Asymmetry of the arterial supply may also explain why autonomous adenomas occur much more often in the right lobe in both children [4] and adults [31] and in the patients reviewed here (11 out of 14 with available information, table 1).…”

Thyroid Anatomy

“…Arterial supply is bilateral from both the external carotid system and superior thyroid artery and subclavian system with the lower thyroid branch of the thyrocervical trunk. It may be a single thyroid ima artery arising from the brachiocephalic artery [21].…”