[The openings of the inferior thyroid vein(s)]

Because of the importance concerning angiography and approach in neck surgery the venous drainage from the inferior border of the thyroid gland, including its variants, had been reported in numerous times in surgical and anatomic literature. Statistical information on the frequency of opening sites and number of the thyroid veins are rather poor and differ with the variant authors tremendously, due to the small number of patients or preparations investigated. To provide more accurate data are the objectives of this paper. Our issues derive from examinations on cadavers of the dissecting-courses in the years 1987-1992 (n = 168). Preparations showing signs of semiresection of the thyroid gland had been rejected for this study, obviously. In regard to the brachiocephalic veins three groups of venous drainage could be established: A) Exclusive drainage to the right or left brachiocephalic vein or their junction, respectively; B) Combinations of the possibilities shown in A); C) Special cases with supernumerary drainage to other veins of the mediastinum. Besides detailed descriptions of the frequency of the variants found, the discrepancies to the known literature are discussed. Some of the variants described by us have not been mentioned at all.