Electromyographic features of intermittent intraoperative neuromonitorization in the thyroid surgery

Öz

Background: The aims of this study are, to summarize the trick points of intermittent intraoperative neuromonitoring(I-IONM), outlines of electrophysiologic outcomes of electromyography(EMG), and to determine the electrophysiological properties of left and right recurrent laryngeal nerve(RLN) which anatomical lengths are different from each other. Material Method: 34 thyroidectomy cases(27 of total thyroidectomy, 7 of hemithyroidectomy) with use of I-IONM, between June 2016 and June 2017 were retrospectively examined. Predissection(R1, V1) and postdissection(R2, V2) EMG waveforms of the right and left sides' vagal nerve (VN) and RLN were evaluated. Results: There were 29 females and 5 males patients with mean age of 43.85±13.86 years. 61 nerves at risk were successfully evaluated with I-IONM. Mean R1 and R2 amplitudes of the right RLN were 280±10 µV and 270±9µV; the left RLN were 270±10µV and 260±9µV respectively. Mean V1 and V2 amplitudes of the right VN were 210±7µV and 190±7µV; the left VN were 190±5.4µV and 170±5µV respectively. Mean R1 and R2 latencies of the right RLN were 2.03±0.42mS and 2.0±0.46mS; the left RLN were 1.90 ± 0.30mS and 1.96 ± 0.33mS respectively. Mean V1 and V2 latencies of the right VN were 1.91±0.46mS and 1.82±0.52mS; the left VN were 2.01±0.34mS and 2.07±0.38mS respectively. There was no statistically significant difference between the sides in terms of electromyographic waveforms of the VN and RLN. Conclusion: The left RLN has a longer anatomical length than the right RLN but we concluded that the length of the nerve does not affect the amplitude and latency.

Anahtar Kelimeler

• Recurrent laryngeal nerve
• Electromyography
• Neuromonitoring

Tiroid cerrahisinde aralıklı intraoperatif nöromonitorizasyonun elektromiyografik özellikleri

Öz

Amaç: Bu çalışmanın amacı aralıklı intraoperatif sinir monitorizasyonunun(I-IONM) püf noktalarını özetlemek ve anatomik uzunlukları birbirinden farklı olan sol ve sağ rekürren laringeal sinirin (RLN) elektrofizyolojik özelliklerini belirlemektir. Materyal Method: Haziran 2016-Haziran 2017 tarihleri ​​arasında I-IONM kullanan 34 tiroidektomili hasta (27'i total tiroidektomili, 7'i hemitiroidektomili ) retrospektif olarak incelendi. Predisseksiyon (R1, V1) ve post-disseksiyon (R2, V2) sağ ve sol tarafın vagal siniri (VN) ve RLN'nin EMG dalga formları değerlendirildi. Bulgular: Yaş ortalaması 43.85 ± 13.86 olan 29 kadın ve 5 erkek hasta vardı. 61 sinir I-IONM ile başarıyla değerlendirildi. Sağ RLN'nin ortalama R1 ve R2 genlikleri 280 ± 10 µV ve 270 ± 9µV idi; sol RLN sırasıyla 270 ± 10 µV ve 260 ± 9 µV idi. Sağ VN'nin ortalama V1 ve V2 genlikleri 210 ± 7µV ve 190 ± 7µV idi; sol VN sırasıyla 190 ± 5.4µV ve 170 ± 5µV idi. Sağ RLN'nin ortalama R1 ve R2 gecikmeleri 2.03 ± 0.42mS ve 2.0 ± 0.46mS; sol RLN sırasıyla 1.90 ± 0.30mS ve 1.96 ± 0.33mS idi. Sağ VN'nin ortalama V1 ve V2 latensleri 1.91 ± 0.46mS ve 1.82 ± 0.52mS idi; sol VN sırasıyla 2.01 ± 0.34mS ve 2.07 ± 0.38mS idi. VN ve RLN'nin EMG dalga formları açısından taraflar arasında istatistiksel olarak anlamlı bir fark yoktu. Sonuç: Sol RLN'nin sağ RLN'den daha uzun anatomik uzunluğu vardır, ancak sinirin uzunluğunun genlik ve gecikmeyi etkilemediği sonucuna vardık.

Anahtar Kelimeler

• Rekürren larengeal sinir
• Sinir Monitorizasyonu
• EMG

Kaynakça

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