Developing control algorithms of a voluntary cough for an
artificial bioengineered larynx using surface electromyography
of chest muscles: A prospective cohort study
Department of Otolaryngology, Head and
Neck surgery, The Ear Institute, University
College of London, London, UK
M.S. Banus, Department of Otolaryngology,
Head and Neck surgery, The Ear Institute,
University College of London, London, UK.
The Rhinology and Laryngology research
charity, Grant/Award Number: HMPV
Objective: This prospective cohort study investigates the prediction of a voluntary
cough using surface electromyography (EMG) of intercostal and diaphragm muscles,
to develop control algorithms for an EMG-controlled artificial larynx.
Setting: The Ear Institute, London.
Main outcome measures: Electromyography onset compared to voluntary cough
exhalation onset and to 100 ms (to give the artificial larynx the time to close the
bioengineered vocal cords) before voluntary cough exhalation onset, in twelve
Results: In the 189 EMG of intercostal muscle-detected voluntary coughs, 172
coughs (91% CI 70-112) were detected before onset of cough exhalation and 128
coughs (67.6% CI 33.7-101.7) 100 ms before onset of cough exhalation. In the 158
EMG of diaphragm muscle-detected voluntary coughs, 149 coughs (94.3% CI 76.3-
112.3) were detected before onset of cough exhalation and 102 coughs (64.6% CI
26.6-102.6) 100 ms before onset of cough exhalation. More coughs were detected
before onset of cough exhalation when combining EMG activity of intercostal and dia-
phragm muscles and comparing this to intercostal muscle activity alone (183 coughs
[96.8% CI 83.8-109.8] vs 172 coughs, P = .0294). When comparing the mentioned
combination to diaphragm muscle activity alone, the higher percentage of detected
coughs before cough exhalation onset was not found to be significant (183 coughs vs
149 coughs, P = .295). In addition, more coughs were detected 100 ms before onset
of cough exhalation with the mentioned combination of EMG activity and comparing
this to intercostal muscles alone (149 coughs [78.8% CI 48.8-108.8] vs 128 coughs,
P = .0198) and to diaphragm muscles alone (149 coughs vs 102 coughs, P = .0038).
Conclusions: Most voluntary coughs can be predicted based on combined EMG sig-
nals of intercostal and diaphragm muscles, and therefore, these two muscle groups
will be useful in controlling the bioengineered vocal cords within the artificial larynx
during a voluntary cough.
Total laryngectomy remains the mainstay of treatment for intermedi-
ate- to advanced-stage laryngeal cancer.
Due to the impact of this
type of surgery on social, emotional and psychological well-being,
alternative treatments have been sought in order to improve stan-
dard care. Organ-preserving chemoradiotherapy plays an important
role in the management of laryngeal carcinoma but is confined to
Accepted: 19 October 2017
© 2017 John Wiley & Sons Ltd wileyonlinelibrary.com/journal/coa Clinical Otolaryngology. 2018;43:562–566.