1 — Isthmus; 2 — Thyroid gland, lobe; 3 — Median cricothyroid ligament; 4 — Thyroid cartilage; 5 — Pyramidal lobe; 6 — Cricothyroid; 7 — Trachea; 9 — Superior thyroid artery; 8 — Superior parathyroid gland; 10 — Inferior parathyroid gland; 11 — Inferior thyroid artery; 12 — Oesophagus; 13 — Vagus nerve [X]; 14 — Sternocleidomastoid; 15 — Platysma; 16 — Parathyroid gland; 17 — Thyroid gland; Fibrous capsule; 18 — Pretracheal layer; 19 — Thyroid gland; 20 — Investing layer; 21 — Internal jugular vein; 22 — Common carotid artery;
23 — Prevertebral layer
