Introduction: The objective of this study was to analyze the morphometry and anatomical relationships of the thyroid gland through dissection. Materials and Methods: This was a prospective descriptive anatomical study conducted over a 5-month period, from July 7, 2024 to November 27, 2024, involving dark-skinned anatomical subjects who met the inclusion and exclusion criteria, and were dissected in the autopsy rooms of the pathology departments of Idrissa Pouye General Hospital and Dalal Jamm Hospital. Results: A total of 24 anatomical subjects were dissected. There were 18 males (75%) and 6 females (25%), with a sex ratio (F/M) = 0.33. The mean thyroid diameter was 5.9 cm ± 0.57 (range: 5.1 - 7.32 cm). The mean height of the left lobe was 4.7 cm ± 0.78 (range: 3.2 - 5.4 cm), and that of the right lobe was 4.61 cm ± 0.93 (range: 2.9 - 6.3 cm). The mean height of the isthmus was 2.3 cm ± 0.74 (range: 1 - 2.41 cm). The left recurrent laryngeal nerve (RLN) passed posterior to the inferior thyroid artery in 16 cases (66.7%), transvascular in 6 (25%), and prevascular in 2 (8.3%). On the right, the RLN was retrovascular in 12 (50%), prevascular in 8 (33.3%), and transvascular in 4 (16.7%). All parathyroid glands found were posterior. Sixteen specimens (66%) had four parathyroids, while five (20%) had two. Conclusion: Thyroid dissection highlighted significant morphometric variability and diverse relationships with the recurrent laryngeal nerves and inferior thyroid arteries, as well as variations in parathyroid gland distribution. Awareness of these variations is critical to preventing post-thyroidectomy complications.
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