[Laryngeal electromyographic characteristics of vocal fold immobility].
OBJECTIVE
To investigate the characteristics of laryngeal electromyography and evoked electromyography in vocal fold immobility.


METHODS
108 cases of vocal fold immobility were analyzed by clinical manifestation and laryngeal electromyography characteristics, including spontaneous potential activity, motor unit potential (MUP) measurement, recruitment pattern analysis and evoked electromyography evaluation.


RESULTS
Neurogenic vocal fold immobility showed a wide variety of abnormal activity. Fibrillation potentials and positive sharp waves were found in patients with laryngeal nerve injuries. For laryngeal paralysis, there was no reaction with LEMG and evoked LEMG. For laryngeal paresis, it showed decreased MUP and decreased recruitment activities with simple pattern recruitment or mixed pattern recruitment, and decreased evoked muscle response potentials were also shown with delayed latency than normal (P < 0.05) in the TA (2.2 +/- 1.0) ms(x +/- s), PCA (2.4 +/- 1.0) ms and lower amplitude in the TA (0.9 +/- 0.7) mV and PCA (1.2 +/- 1.0) mV (P < 0.05). Patients with vocal fold mechanical limitations generally yielded normal LEMG and Evoked LEMG. Patients with neoplastic infiltration of the laryngeal muscles demonstrated decreased LEMG and nearly normal Evoked LEMG with normal latency and lower amplitude.


CONCLUSIONS
General EMG and evoked EMG play a crucial role in the diagnosis of vocal fold immobility.
Xu
Wen
W
Department of Otorhinolaryngology Head Neck Surgery, Beijing Tongren Hospital, Capital University of Medical Sciences, Beijing 100730, China. entwen@trhos.com
Han
De-min
DM
Hou
Li-zhen
LZ
Zhang
Li
L
Zhao
Gong-wei
GW
D000293:Adolescent; D000328:Adult; D000368:Aged; D004576:Electromyography; D005260:Female; D006801:Humans; D007821:Laryngeal Muscles / Q000503:physiopathology; D007823:Laryngeal Nerves / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D014826:Vocal Cord Paralysis / Q000503:physiopathology*; D014827:Vocal Cords / Q000503:physiopathology*; D055815:Young Adult