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motion may be without clinical significance. Further,
Roy et al. showed that laryngoscopic findings are not
consistent from case to case, even in experimentally
induced isolated unilateral superior laryngeal nerve
palsy, a condition probably more homogeneous than that
which presents clinically.17 Respondents identified defi-
cits of gross motion as having the highest positive pre-
dictive value for VFP, despite reporting heavy reliance
on stroboscopic examination in practice. This may reflect
merely that stroboscopy is the standard clinical exami-
nation for patients with a voice complaint in the special-
ized practices of these physicians rather than the use of
examination under stroboscopic light to identify VFP.
Mucosal wave phase asymmetry was deemed the most
useful stroboscopic sign, ranking only fifth in order of
preference despite a report that identified it as correlat-
ing very well with LEMG abnormalities.7 Stroboscopic
signs (phase, amplitude, and frequency) were also
marked by the greatest divergence of opinion regarding
significance, as reflected by the standard error. The few
signs that have been the subject of systematic analysis
in the literature, namely arytenoid rotation8 and unilat-
eral ventricular fold hyperfunction,6 were not regarded
as among the most useful. Reports have proposed a rela-
tionship between contact lesions 9,10 and vocal fold pseu-
docysts11 and VFP. Despite this, respondents thought
that the potential for VFP to be present when such
lesions were identified was very low.
Overall, this investigation reveals that paresis is fre-
quently diagnosed and appears to be a significant clinical
entity in laryngology practices. Diagnosis appears to be
made on the basis of qualitative findings on laryngoscopy,
principally deficits of gross vocal fold motion. Although
stroboscopy is widely used, stroboscopic signs are not con-
sidered the most reliable signs to identify VFP. Electro-
physiologic testing is not used often. Plainly, there exists
no clear consensus on how the diagnosis of VFP should be
made in a given patient, and establishing one will be a
challenge in the absence of tests or findings that are both
reasonably specific and sensitive. Under these circum-
stances, and given the frequency of asymmetric motion in
the larynx, VFP is at risk of being diagnosed uncritically
when no other obvious reason for a patient’s complaint is
evident to the examiner.
The survey format is subject to substantial recall
bias and may give a false impression—likely falsely ele-
vated—of the prevalence of paresis. This survey explic-
itly did not distinguish between superior laryngeal nerve
paresis and recurrent laryngeal nerve paresis, fre-
quently separated in the literature, which may have
caused surveyed physicians to assign less positive pre-
dictive value to the signs under consideration than a
more specific diagnosis. Reasons for the relatively rare
use of LEMG were not investigated; these may have lit-
tle to do with reservations regarding LEMG utility. Most
importantly, the format of the survey necessarily does
not well reflect the method of diagnosis of VFP in clini-
cal practice. Such a diagnosis is rarely made on the basis
of a single element of the evaluation or a single sign con-
sidered by itself, but depends on an educated critical
synthesis of the clinical evidence. Physicians may form
an impression of the likelihood of a given diagnosis
based on the history, which then informs the physical
examination. In fact, the perceived likelihood of VFP
based on symptoms and clinical evolution of the com-
plaint may significantly affect the perceived positive pre-
dictive value of a given laryngoscopic sign. Despite these
limitations, this data may form a useful basis for further
consideration of this challenging topic.
CONCLUSION
Surveyed laryngologists diagnose VFP frequently,
relying principally on laryngeal strobovideolaryngoscopy
to make the diagnosis. Among laryngoscopic signs, gross
motion abnormalities were judged to have the highest
positive predictive value for VFP, followed by abnormal-
ities in the mucosal wave. Opinion varied most about
the importance of these. LEMG was infrequently used to
assess for VFP and was considered to have only moder-
ate sensitivity for the diagnosis. Given the perceived
clinical importance of VFP, directed investigation is nec-
essary to refine diagnostic accuracy.
BIBLIOGRAPHY
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Otolaryngol Head Neck Surg 2000;122:537–541.
3. Heman-Ackah YD, Barr A. Mild vocal fold paresis: understanding clinical
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4. Rubin AD, Praneetvatakul V, Heman-Ackah Y, Moyer CA, Mandel S,
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TABLE III.
Respondent Opinion Regarding Positive Predictive Value of
Laryngoscopic Findings in VFP.
Examination finding Average % Error r
Slow/sluggish motion 74.9 3.0 22.8
Decreased VF adduction 67.3 3.5 26.7
Decreased VF abduction 65.4 3.4 26.1
Decreased VF tone 61.1 3.5 26.3
Asymetric MW phase 60.2 4.1 31.3
Hemilarynx atrophy 60.1 4.0 30.8
Unilateral supraglottic hyperfunction 58.9 3.9 29.4
Glottic insufficiency 55.4 3.5 26.8
Asymetric MW amplitude 51.7 4.2 31.7
Asymetric MW frequency 48.6 4.0 30.6
VF height difference 43.5 3.8 28.6
Impairment of arytenoid rotation 42.9 3.6 27.8
Glottic axis deviation 41.3 3.8 29.3
Bilateral supraglottic hyperfunction 32.0 3.3 25
Presence of contact lesion 27.3 2.4 18.1
Presence of pseudocyst 22.3 2.8 21.4
MW 5 mucosal wave; VF 5 vocal fold; VFP 5 vocal fold paresis.
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