The middle thyroid vein: Anatomical and surgical aspects

Background: An issue that has been overlooked in medical literature concerns the prevalence and topographic relationships of the middle thyroid vein (MTV), which have been studied, with a prospective approach, in patients with various thyroid diseases. Methods: MTV prevalence has been investigated in 394 consecutive lobes and a number of different variables (age, gender, thyroid pathology, gland weight) have been considered. Moreover, in cooperation with our Human Morphology Department, we brought to completion a dedicated anatomy report, with the clear objective of providing a detailed anatomic description of MTV. Results: The prevalence of MTV was 38% of the dissected lobes and 62% of operated patients. Most veins arise from the mid region of the thyroid lobe (80%): B, 3, and 2 positions in accordance with our scheme. As far as thyroid pathology is concerned, we found that the presence of MTV was more frequent in hyperthyroidism and large goiters (p < 0.05). Conclusions: A better understanding of the anatomic variability in MTV may be useful not only to minimize the risk of bleeding, but it also can help to perform a more accurate dissection with the goal of preserving the laryngeal nerves and parathyroid glands, especially because of its location and relationships with other adjacent structures.