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significantly variable across testing sessions. It is reasonable
to expect greater variability in an office setting without these
control parameters. Laryngeal electromyography holds much
potential to be a useful clinical tool available for diagnosing
movement disorders of the larynx. To obtain the maximum
benefit from clinical LEMG, a universal standardized proto-
col that is feasible within a typical in-office setting should be
developed. Further prospective research studies should con-
sider the evaluation of (1) hooked wire electrode use for con-
tralateral comparisons and (2) vocal frequency and intensity
controls to regulate muscle recruitment to maximize the
interpretability of LEMG measures. Quantitative LEMG
techniques that may be used for clinical application are now
feasible and relatively inexpensive and should be explored.
Laryngeal electromyography follow-up diagnostics would
also be useful for data comparisons. A recent article by
Sataloff et al stated that follow-up LEMG is not performed in
up to 90% of cases if visual inspection of the larynx demon-
strates improved vocal fold mobility.
29
Follow-up testing
could provide useful reliability data for LEMG as performed
in the clinic.
Data from this study offer insight into the importance
of using loading controls (control of intensity and fre-
quency) in order to obtain the most accurate data from
clinical LEMG. Methodologically, the use of hooked wire
LEMG may be a good alternative to needle electrodes for
several reasons, including freeing the clinician to direct
the patient to control pitch and loudness levels, allowing
for simultaneous measures, and reducing the possibility
of artifact from needle electrode movement. With today’s
technology, control of vocal frequency and intensity can
be easily accomplished through visual feedback to the
patient using an inexpensive headset microphone con-
nected to a laptop computer or other mobile device run-
ning commercially available sound intensity applications.
In addition, quantitative signal processing tools are
becoming more accessible and less expensive, allowing
for the real-time use of quantitative techniques such as
RMS to improve the quality of in-office assessments and
the use of rise-time functions to confirm optimal elec-
trode placement.
30
In closing, LEMG is a clinical assessment tool that has
not yet reached its full potential. The means to make LEMG
a more quantitative and reliable assessment method are
available and ready for usage to improve the clinical reli-
ability and usefulness of this potentially important diagnos-
tic method.
Acknowledgments
The authors would like to thank the participants for undergoing
multiple LEMG procedures for this study, and the University of
Kentucky College of Health Sciences Office of Research for sup-
porting this project through pilot funding.
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with
respect to the research, authorship, and/or publication of this
article.
Funding
The author(s) disclosed receipt of the following financial support
for the research, authorship, and/or publication of this article: The
University of Kentucky College of Health Sciences Office of
Research supported this project through pilot funding.
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