The Modern Thyroid Operation Slide 1. Setup of a functional neuromonitoring in thyroid surgery in Department of Otolaryngology- Head and Neck Surgery, Kaohsiung Medical University, Taiwan Feng-Yu Chiang, MD Department of Otolaryngology Kaohsiung Medical University, Taiwan E-mail: fychiang@kmu.edu.tw

The modern thyroid operation Eradicate thyroid disease A safe thyroid operation Intra-operative evidence

Eradicate thyroid disease Total lobectomy Total thyroidectomy Neck dissection (Central or Lateral) Resection of upper aerodigestive tract I-131 therapy

A safe thyroid operation Preserve RLN and EBSLN Preserve parathyroid function

Intra-operative evidence Anatomic integrity - High-resolution photographs Functional integrity - IONM of RLN - Intact blood supply to parathyroid

Preservation of RLN

Recurrent laryngeal nerve palsy Most common and serious complication The leading reason for medicolegal litigation

Routine identification of RLN Lower rates of RLN palsy Gold standard of RLN treatment

Intra-Operative NeuroMonitoring (IONM)

Applications of IONM Prevent RLN injury Localize and identify RLN Predict vocal function Elucidate mechanism of RLN injury Help preserve parathyroid

ET tube KMU ENT

After intubation and neck fully positioned, we routinely check the electrodes position with laryngofiberoscopy from the nose. 17 17 17

Video of RLN approach

IONM is useful and helpful for Anatomic variants of RLN Difficult thyroid operation

Anatomic variants of RLN (Extralaryngeal branches, Non-RLN, Distorted RLN…etc) - important factors: RLN injury False results of IONM

Extralaryngeal branches of RLN Branch to trachea Branch to esophagus Branch to inferior constrictor muscle Anterior branch Posterior branch

Bifurcated RLN

Non-recurrent RLN

Video of detecting Non-RLN

Video of mapping Non-RLN

Video of Non-RLN

Difficult thyroid operation (Recurrent, substernal or large goiter , Thyroid cancer) Early localization & Definite identification An important step to prevent RLN injury

Localization

Reoperation

RLN can be displaced to any direction in this circumstance.

Substernal or large goiter

Palsy rates in 3 operation periods IONM - + NAR 852 173 612 Palsy rate Temporary Permanent 5.7% 5.0% 0.7% 6.4% 5.8% 0.6% 0.65% 0% This slide show the palsy rates of my series at 3 different op period. So, During learning of IONM, the palsy rates will not change. In period 3, the palsy rate was significantly reduced to less than 1% after understanding the mechanism of nerve injury and improving the surgical technique.

Preservation of EB-SLN

The path of EB-SLN can be divided into type 1, 2a and 2b The path of EB-SLN can be divided into type 1, 2a and 2b. Type 2a and 2b have higher risk of injury during clamping the sup pole vessels.

Video of EB-SLN We can identify the nerve by watching the twitch of CT muscle.

Preservation of parathyroid function Preserve parathyroid with intact blood supply Auto-transplantation for devascularized parathyroid

Parathyroid with intact blood supply (1)