SUBTOTAL THYROIDECTOMY

1. SUBTOTAL THYROIDECTOMY The thyroid operation is considered by many to be at the pinnacle of endocrine surgery

2. Thyroid Surgery • Most endocrine surgeons agree that an accurately performed thyroidectomy requires both experience and technical ability • National endocrine surgical associations- strives for the creation of centers of excellence for the future training of endocrine surgeons

3. Unacceptably high incidences of major complications, like: - recurrent laryngeal nerve palsies - permanent hypoparathyroidism are still reported in the surgical literature.

4. RLN function is tested by placing the surgeon’s finger in the prevertebral space and palpating the aritenoid cartilage movements as the nerve is stimulated using the nerve stimulator

5. Suspensory ligament of Berry : Its relationship to recurrent laryngeal nerve and anatomic examination of 24 autopsies Authors SASOU S. (1) ; NAKAMURA S.-I. (1) ; KURIHARA H. (2) ; Authors Affiliations (1) Division of Pathology, Central Clinical Laboratory, School of Medicine, Iwate Medical University, 19-1 Uchimaru, Morioka 020-8505, Iwate, JAPON(2) Kurihara Thyroid Clinic, Morioka 020-0015, JAPON

6. Background. It is important to clarify the relationship between the recurrent laryngeal nerve (RLN) and the ligament of Berry to prevent damage to the RLN in thyroid surgery. The purpose - to identify this relationship to prevent surgical complications. Methods. Among the 486 thyroid surgery cases, 689 RLNs were identified and their course detected. Topography of the laryngotracheoesophageal region and the histology of the ligament of Berry were studied in detail in 25 autopsied cadavers. Results. All nerves identified by surgery and autopsy were located laterodorsally to the ligament of Berry. They were clearly separated, and no nerve penetrated the ligament nor was medially located to it. The ligament of Berry strongly connected the thyroid gland to the trachea and was identified as a whitish connective tissue band. Conclusions. It was confirmed that the RLN never penetrates the ligament of Berry but is located laterally to it. From these topographic findings, no injury to the RLN will occur from a separation close to the goiter in thyroid surgery

7. 1. Experience, 2. Sound judgment, 3. Meticulous technique 4. Adequate training are the hallmarks required to eliminate POSTOPERATIVE MORBIDITY

8. Thyroid Surgery • It would be prudent to design appropriate training programs • Introduce uniform guidelines and standards for performing these operations for the whole country

9. SUBTOTAL THYROIDECTOMYINDICATIONS Are decreasing • Thyrotoxicosis • Antithyroid drugs resistance • Recurrence after an apparently successful medication • Pressure symptoms • Cosmetic effect- large goitre • Inflammatory conditions • Riedel’s struma • Hashimoto’s disease

10. Preoperative preparationThyrotoxicosis • ATS drugs until an euthyroid state is reached • ATS drugs block the synthesis of thyroxine but do not inhibit the release of the hormone from existing colloid stores: 3w-3m~Q.colloid • When euthyroid than LUGOL-potassium iodide solution, 10 days • Postop. tachycardia- beta blockers

11. Thyroid Surgery • The tubercle of Zuckerkandl is a thickening of thyroid tissue that is located at the most postero-lateral edge of the thyroid gland • Close proximity with PTs and RLN

12. Laryngeal Nerves

13. OPERATIVE STEPS • Kocher incision • Dissection of the sup. and inf. skin flaps from thyroid cartilage down to the suprasternal notch- - ! arch connecting the 2 AJV • Retractor for skin flaps • Large goitre- division of SH/ST muscles in the sup. 1/3 (avoid injury to the motor nerve supply) • Free the ant. margin of SCM from the ST muscle • Midline vertical incision between the SH. muscles from the thyroid notch to suprasternal notch

14. Crease line incision above the jugular notchRaising the skin flapsStay anterior to the AJV- bloodless dissection

15. Strap muscles are separated by opening the linea albaSH/ST divided in the sup.1/3rd- avoid injury to the nerve supply (ansa cervicalis-inferiorly)

16. OPERATIVE STEPS • Pick up loose fascia over the thyroid and incise it- cleavage plane between the thyroid gland and ST muscle • Working in a proper cleavage plane, the delivery of the gland may be facilitated by forefingers dissection • MTV ligated, • Branches of STA

17. Freeing the lobe using lateral approachLigate MTV.

18. OPERATIVE STEPS • Blunt dissection of the upper pole, pushing away from the larynx • STA/STV exposed above their point of entry into the gland • Lower pole- free from inf. veins • Exposing the ITA- identify RLN, PTs • Leave paratracheal thyroid tissue- clamping the parenchyma • Divide the isthmus • Subtotal resection of the lobe

19. Excessive dissection of the RLN resulted in neuropraxia due to interference with its neural blood supply

20. Line of resection for subtotal thyroidectomy

21. Ligate the ITVMyoraphy of the strap muscles

22. Types of thyroidectomies

23. Choice of surgical technique Potential benefits and complications • Pts. with MNG- the main reason to perform bilateral subtotal thyroidectomy is: • a presumed lower incidence of complications • an attempt to maintain the euthyroid status without thyroxine replacement

24. Disadvantages • High recurrence rate and increased surgical morbidity during reoperation • Some pts. still require thyroxine replacement • Unrecognized malignancy- SBT=inadequate surgery

25. TT- Advantages • Adequate removal of the disease • Prevention of the recurrence • Avoidance of the need for completion surgery

26. How to reduce the risk of complications • Well trained endocrine surgeon • Technique of capsular dissection, staying close to the thyroid gland • Preserving the blood supply to the PT • Identification of the RLN