Variations in superior thyroid artery: A selective angiographic study

Abstract

Aim:To investigate variations in superior thyroid artery (STA) based on digital subtraction angiography (DSA).Materials and Methods:Twenty five angiography studies of 15 pts performed between June 2010 and December 2012 were retrospectively evaluated. These patients underwent DSA of the head and neck region as a part of their superselective neoadjuvant intra-arterial chemotherapy protocol for treatment of laryngeal and hypopharyngeal cancers. Depending upon the location of the tumor, unilateral or bilateral arteriograms of common carotid artery (CCA), external carotid artery (ECA), and STA were performed. Arteriograms were evaluated for the site of origin and branching pattern of STA. STA anatomy was ascribed to one of the three branching patterns.Results:A total of 25 angiograms were evaluated, including 14 right and 11 left. On the right side, STA was noted to arise from ECA in 10 (71.5%), bifurcation of CCA in 3 (21.5%), and CCA in 1 (7%) patient. Left STA was seen to arise from ECA in 8 (72.5%), bifurcation of CCA in 2 (18.5%), and internal carotid artery (ICA) in 1 (9%) patient. Type III branching pattern (non-bifurcation, non-trifurcation) was found to be the most frequent (52%). Infrahyoid branch was found to be the most consistent in terms of its origin from STA.Conclusions:Origin of STA is predictable, arising from ECA in more than 70% cases. Branching pattern of STA, following origin from ECA, is, however, highly variable. Knowledge concerning the origin and branching pattern of STA is essential in enhancing precision and decreasing morbidity related to the surgical and interventional radiological head and neck procedures.

Congenital thyroid hemiagenesis with thyroid nodules—Role of TI-RADS to prevent long term thyroid replacement therapy

“…Absence of inferior and/or superior thyroid arteries with absence of thyroid tissue seems to be the most reliable tool for confirmation of the diagnosis. In the first case we noted an absence of inferior thyroid artery of the left side while in second case both the arteries were absent [11], [12]. CT scan however remains an expensive investigation with risk of radiation and contrast injection, when compared to high resolution sonography.…”

Anatomical considerations of the superior thyroid artery: its origins, variations, and position relative to the hyoid bone and thyroid cartilage

“…The STA is a consideration in many surgeries and accurate clinical anatomical knowledge of the STA is important to minimizing surgical complications. Most anatomical studies of the STA have been done by direct observation of its anatomy in the body, although there are a small number of angiographic studies [ 5 7 12 13 14 ]. These studies have mostly been concerned with identifying the pattern of origin of the STA or, occasionally, the thickness of its branches.…”

“…Gupta et al [ 7 ] conducted an angiographic study of 25 STAs of cadavers and identified their pattern of origin. In their study, the STAs on the right side of the body arose from the ECA, CB, CCA, and in one case, from the internal carotid artery (ICA).…”

“…The STA arises from the external carotid artery (ECA) just below the level of the greater cornu of the hyoid bone and ends in the thyroid gland. It distributes twigs to the adjacent muscles, the upper larynx, and the neck region; and it distributes numerous branches to the thyroid gland and overlying skin [ 5 6 7 ]. Surgical procedures that involve the STA include radical neck dissection, cricothyroidotomy, thyroidectomy, reconstruction of an aneurysm, carotid endarterectomy, treatments for cancer, diagnostic and therapeutic catheterization, and plastic surgery [ 5 7 8 9 ].…”

“…Most of the studies of the STA have focused on the possible variations in its origin. In general, textbooks state that it arises from the ECA as a main branch, but Gupta et al [ 7 ] reported that it can originate from the ECA, from the bifurcation of the common carotid artery (CCA), or from the CCA [ 8 10 11 ].…”