Electromyographic features of intermittent intraoperative neuromonitorization in the thyroid surgery

Year 2020, , 131 - 137, 23.08.2020

Serdar Gümüş , Edip Yılmaz , Yusuf Yağmur

https://doi.org/10.37696/nkmj.719020

Abstract

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.

Keywords

Recurrent laryngeal nerve, Electromyography, Neuromonitoring

Tiroid cerrahisinde aralıklı intraoperatif nöromonitorizasyonun elektromiyografik özellikleri

Abstract

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.

Keywords

Rekürren larengeal sinir, Sinir Monitorizasyonu, EMG

References

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