2018 Section 6 - Laryngology, Voice Disorders, and Bronchoesophalogy
S.-K.
Baek et
al.
/ Auris
Nasus
Larynx
44
(2017)
583 – 589
the dissection of
the
thyroid
superior pole,
similar
to
the
during
3.5.
Comparison
between
open
thyroidectomy
and
there was no definite
traditional surgical method. Consequently,
thyroidectomy
robotic/endoscopic
to
the
EBSLN
in
the
study
population.
However,
injury
F0, Maximal
pitch,
GRBAS
scale,
and
VHI-30
score
The
that
the
F0
and Maximum
pitch,
which
may
be
considering
not
significantly
different
between
two
groups
of
the
were
the
function
of EBSLN,
exhibited
a
significant
associated with
who
underwent
open
thyroidectomy
or
robotic/
patients
difference
according
to
IONM,
even
if
identification
and
thyroidectomy
(Supplementary
Tables
2
and
3,
endoscopic
of
the
EBSLN
were
not
performed
directly,
neuromonitoring
0.05). When
the study population was divided based on the
p >
IONM may
render minimal damage of
the nerve potentially
the
techniques,
the
number
of
patients
in
each
group was
surgical
avoidable.
and may
be
associate with
this
insignificant
results.
small
it may
be
difficult
to
identify
the mechanism
to
Although
the
risk
of EBSLN
injury
through
IONM
of
the RLN, the RLN anatomical
decrease
be
associated with
the
anatomical
finding
that
it may
4. Discussion
innervate
the
cricothyroid
muscle.
Previous terminal
can
Phonation
studies
change
after
thyroidectomy
has
been
considered
of
cadaver
larynges
revealed
that
branches
of
result
from
numerous
factors,
including
laryngeal
neural
EBSLN
communicate with
branches
of
the RLN,
and
this
to
the
endotracheal
intubation
trauma,
cricothyroid
dysfunc-
is
called
the
human
communicating
nerve
[17 –
damage,
branch
strap
muscle
malfunction,
laryngotracheal
fixation,
and
When
the
EBSLN
is
electrically
stimulated,
activation
tion,
19] .
reaction laryngeal
to
the
operation
[5,8 – 10] .
In
particular,
the
endolaryngeal
muscles
was
revealed
in
70% – 80%
of
psychological
of
damage that may numerous to
the
nerve
is
one
of
the
critical morbidities
and [4] .
this phenomenon
is used
as
the
IONM method demonstrated
for
patients, EBSLN
result
in a significant effect on
the quality of
life. Thus,
In
contrast,
a
previous activated
study
that
studies
have
examined
whether
IONM
during nerve
can
be
by
the
RLN
via
reverse
cricothyoid muscles
thyroidectomy
communication
is
beneficial
in
reducing
the
laryngeal
of
the
human
communicating
nerve
[20] . As
a
rate.
Although
a
non-randomized
study
suggested
reversible
damage
of RLNs
by minimal
trauma,
such
as of
paralysis
result,
rates
of in
postoperative
RLN
paralysis
in
patients resulted
with
or
heating, may
result
in
the
temporary
dysfunction
lower IONM
traction
[11] ,
other
randomized
studies,
IONM
in
no
cricothyroid muscles. NIM system emits
reduction
in
permanent
RLN
paralysis
compared
audible
sound
and
shows
EMG
signal
significant
visualization
alone,
even
in
high
risk
patients
with
subtle
stimulations
such as
traction or heating
that
with
change under
resection
or
reoperation
due
to
recurrent
thyroid
occur
nerve
damage, which may of RLN. Actually, in
be
useful
to
prevent
the
extended diseases significant temporary
can
[12 – 14] .
However,
IONM
resulted
in
a
statistically
trauma
present
study,
operators
minimal
discontinued
decrease EBSLN
in
the
risk
of
early
phonation
changes
or
surgical
procedure
to minimize
traumas
of
RLN
injury
after
surgery
[13,15] .
NIM
system
indicated
impending
trauma
of
RLN
and
when
the
present
study,
female
patients
without
evidence
of
reassume
operation
after
confirming
the
safety
of
RLN.
In
then
nerve
paralysis
were
evaluated
using
various
voice
this
effort
to prevent minimal
trauma of
the RLN
through
laryngeal analysis
Thus,
methods
after
thyroidectomy.
Similar
to
previous
explain
the
significant
reduction of
early phonation
IONM may
a
significant
decrease
in
phonation
changes was
seen
after
thyroidectomy.
studies, during
changes
the
early
period
within
postoperative
1
month.
In
the
total
thyroidectomy
group
had
significant according
particular, differences
5.
Limitation
of
the
study
in F0
and
the maximum pitch of
the VRP
IONM
in
comparison
with
the
hemithyroidectomy
group.
the
present
study,
we
did
not
routinely
identify
and
In
to
this
difference
between
hemithyroidectomy
and
the EBSLN when
dissecting
the
thyroid
superior
pole. voice voice
Expectedly,
monitor Further outcome
thyroidectomy groups may
result
from
the
larger
extent of
study
is
needed
to
evaluate
the
differences
in
total
dissection
in
total
thyroidectomy. the maximum
after
thyroid
surgery
using
multi-parametric
surgical
reduction
in F0
and
pitch
of
the VRP
are
depending
on
the
use
of
IONM
for
the
EBSLN.
The
evaluation
associated with EBSLN
injury
[16] . Even
if
the
clinical of RLN
mainly
of EBSLN
injury
are
less
critical
than
those
symptoms
6.
Conclusion
injury,
the
reduced
F0
and and
difficulty important
in
producing
high-pitch
sensitive
issues
in
female patients.
that IONMduring
thyroid surgery resulted
Our study suggests
sound may be
the
study population of
the present subjective
study was
restricted
to
better
outcomes
regarding
the F0
and
high-pitch
voice
in
the
Thus,
in
patients.
Even
if
the
assessments significantly
of
voice,
postoperative
period,
particularly
in
total
thyroidectomy
female
early
as
GRBAS
and
VHI,
were
not
different
Although
it
may
not
benefit
the
permanent
voice
such
patients. outcome thyroid transient
to
the
use
of
IONM,
the
assessment
scores
showed
a
from
3 months
after
operation,
use
of
IONM
during reduce
according tendency
to
increase during
the early period. However, although
surgery
appears
to
be
an
effective
method
to
in
subjective
findings were not definite,
the
reductions
voice
alteration
after
thyroid
surgery.
changes
in objective values,
including
the F0
and
the maximum pitch of
indicate a partial
impairment of EBSLN
function. the RLN
the VRP may
Acknowledgments
the
present
study, we performed
IONM
for only
In
ligation of
superior
thyroid vessels with capsular
research
was
supported
by
the
Korea
Health through
and peripheral
This
to minimize
the
injury
to
the EBSLN
(grant
number: HI14C0748)
dissection was performed
Technology R&D Project
116
Made with FlippingBook HTML5