blood and nerve supply of thyroid.pptx

The slide is of blood supply and nerve supply of the Thyroid gland. It can be used by MBBS Anatomy students.

1. THYROID GLAND : BLOOD SUPPLY , NERVE SUPPLY AND APPLIED NAME – PRAVIN PANDEY ROLL NO. – 68 BATCH – 2021-22

2. CONTENTS ARTERIAL SUPPLY VENOUS DRAINAGE NERVE SUPPLY APPLIED

3. ARTERIAL SUPPLY Gland is highly vascular Supplied by following arteries: 1. SUPERIOR THYROID ARTERY 2. INFERIOR THYROID ARTERY 3. THYROIDEA IMA ARTERY 4. ACCESSORY THYROID ARTERY

4. 1. SUPERIOR THYROID ARTERY Branch of EXTERNAL CAROTID ARTERY. Runs downward and forward in company with external laryngeal nerve, leaves near upper pole. At apex – divides into Anterior and Posterior branches.

5. ANTERIOR BRANCH : Desce nds along anterior border of lobe. : Continues along the upper border of isthmus. : Anastomose with its fellows of opposite side.

6. POSTERIOR BRANCH : Descends along posterior border of lobe. : Anastomose with ascending branch of inferior thyroid artery. SUPERIOR THYROID ARTERY supplies: Upper one-third of lobe. : Upper half of isthmus.

7. 2.INFERIOR THYROID ARTERY Branch of thyrocervical trunk from the first part of subclavian artery. Runs upward along medial border of scalenus anterior. Related to RECURRENT LARYNGEAL NERVE. This nerve presents variable relationship with artery .

8. VARIABLE RELATIONSHIP OF ARTERY WITH NERVE

9. Inferior Thyroid Artery gives 4 or 5 branches. One ascending branch anastomoses with posterior branch of Superior Thyroid Artery. Supplies : Lower two-third of lobe. : Lower half of isthmus.

10. 3. THYROIDEA IMA ARTERY ( 30% cases) Branch of brachiocephalic trunk or, May arise directly from arch of aorta. Enters isthmus from below. 4. ACCESSORY THYROID ARTERIES Arise from tracheal or oesophageal arteries.

11. VENOUS DRAINAGE Venous blood from gland is drained by 3 set of veins : 1. SUPERIOR THYROID VEIN 2. MIDDLE THYROID VEIN 3. INFERIOR THYROID VEIN. 4. THYROID VEIN (OF KOCHER) (present sometime).

12. 1. SUPERIOR THYROID VEIN : Emerge at upper pole. : Runs upward and laterally. : Drain into Internal Jugular Vein. 2. MIDDLE THYROID VEIN : Short and wide : Emerge at middle of lobe. : Drain into Internal Jugular Vein.

13. 3. INFERIOR THYROID VEIN : Emerge at lower border of isthmus. : Form plexus in front of trachea. : Drain into Left Brachiocephalic Vein. 4.THYROID VEIN ( OF KOCHER) : Emerge between middle and Inferior thyroid veins. : Drain into Internal Jugular Vein.

14. NERVE SUPPLY Supplied by both sympathetic and parasympathetic nerve fibres. 1. PARASYMPATHETIC SUPPLY : from VAGUS and RECURRENT LARYNGEAL NERVES. 2. SYMPATHETIC SUPPLY : from SUPERIOR , MIDDLE and INFERIOR CERVICAL sympathetic ganglion. (Mainly from MIDDLE one.)

15. CLINICAL CORRELATION 1. THYROIDECTOMY : Removal of gland with true capsule. 2. SUBTOTAL THYROIDECTOMY : Posterior parts of both lobes are left behind. Done to avoid : - Risk of removal of parathyroid glands. - Postoperative myxoedema due to thyroid hormone deficiency.

16. 3. LIGATION OF THYROID ARTERIES DURING THYROIDECTOMY. AT APEX : Superior thyroid artery ligated CLOSE to the apex. Of thyroid lobe to avoid injury to external laryngeal nerve . AT BASE : Inferior thyroid artery ligated away from the base. To avoid injury to recurrent laryngeal nerve.

17. BIBLIOGRAPHY Textbook of Anatomy – Vishram singh (3 rd edition). Gray’s Anatomy

18. THANK YOU..