Deep brain stimulation (DBS) is a promising new therapy for patients with spasmodic dysphonia (SD). The preliminary results from our randomized controlled trial showed good clinical effects with unilateral left thalamic stimulation in 6 right- handed patients. This suggests that the pathological process underpinning SD may have a “hemisphere dominant” pathway. We describe 2 patients with concurrent essential tremor and SD who had previously undergone bilateral thalamic DBS for their limb tremor. Both patients experienced an unanticipated improvement of their SD symptoms. One patient was right-handed, and the other was mixed left-handed. To investigate the amount of SD improvement following DBS therapy in each hemisphere, 4 different settings were tested: both sides on, left side on, right side on, and both sides off. Both patients most improved following bilateral stimulation. There was, however, a powerful unilateral benefit in both patients with only a small additional benefit from bilateral stimulation. The right-handed patient improved most with left-hemisphere stimulation whereas the mixed left-handed patient improved most with right hemisphere stimulation. There was some discrepancy between the two tests applied in the second patient reflecting the known difficulties to evaluate vocal symptom improvement in SD. We discuss the possible correlation of handedness and speech hemisphere dominance as well as the need for more reliable tests to measure SD severity. Ultimately, we recommend a bilateral approach for future studies, using a patient perception test as the primary outcome and functional imaging to further investigate the correlation of handedness and the amount of hemisphere dominance in SD.

1.
Asgeirsson
H
,
Jakobsson
F
,
Hjaltason
H
,
Jonsdottir
H
,
Sveinbjornsdottir
S
.
Prevalence study of primary dystonia in Iceland
.
Mov Disord
.
2006
Mar
;
21
(
3
):
293
8
.
[PubMed]
0885-3185
2.
Laryngeal Dystonia [Internet]. NORD (National Organization for Rare Disorders). [cited 2019 Jun 13]. Available from: https://rarediseases.org/rare-diseases/laryngeal-dystonia/
3.
Benabid
AL
,
Pollak
P
,
Gervason
C
,
Hoffmann
D
,
Gao
DM
,
Hommel
M
, et al.
Long-term suppression of tremor by chronic stimulation of the ventral intermediate thalamic nucleus
.
Lancet
.
1991
Feb
;
337
(
8738
):
403
6
.
[PubMed]
0140-6736
4.
Vidailhet
M
,
Jutras
MF
,
Grabli
D
,
Roze
E
.
Deep brain stimulation for dystonia
.
J Neurol Neurosurg Psychiatry
.
2013
Sep
;
84
(
9
):
1029
42
.
[PubMed]
0022-3050
5.
Poologaindran
A
,
Ivanishvili
Z
,
Morrison
MD
,
Rammage
LA
,
Sandhu
MK
,
Polyhronopoulos
NE
, et al.
The effect of unilateral thalamic deep brain stimulation on the vocal dysfunction in a patient with spasmodic dysphonia: interrogating cerebellar and pallidal neural circuits
.
J Neurosurg
.
2018
Feb
;
128
(
2
):
575
82
.
[PubMed]
0022-3085
6.
Hintze
JM
,
Ludlow
CL
,
Bansberg
SF
,
Adler
CH
,
Lott
DG
.
Spasmodic Dysphonia: A Review. Part 1: Pathogenic Factors
.
Otolaryngol Head Neck Surg
.
2017
Oct
;
157
(
4
):
551
7
.
[PubMed]
0194-5998
7.
Shoffel‐Havakuk
H
,
Marks
KL
,
Morton
M
,
Johns
MM
,
Hapner
ER
.
Validation of the OMNI vocal effort scale in the treatment of adductor spasmodic dysphonia.
The Laryngoscope [Internet]. 0(0). Available from: https://onlinelibrary-wiley-com.ezproxy.library.ubc.ca/doi/abs/10.1002/lary.27430
8.
Stewart
CF
,
Allen
EL
,
Tureen
P
,
Diamond
BE
,
Blitzer
A
,
Brin
MF
.
Adductor spasmodic dysphonia: standard evaluation of symptoms and severity
.
J Voice
.
1997
Mar
;
11
(
1
):
95
103
.
[PubMed]
0892-1997
9.
Oldfield
RC
.
The assessment and analysis of handedness: the Edinburgh inventory
.
Neuropsychologia
.
1971
Mar
;
9
(
1
):
97
113
.
[PubMed]
0028-3932
10.
Veale
JF
.
Edinburgh Handedness Inventory - Short Form: a revised version based on confirmatory factor analysis
.
Laterality
.
2014
;
19
(
2
):
164
77
.
[PubMed]
1357-650X
11.
Risch
V
,
Staiger
A
,
Ziegler
W
,
Ott
K
,
Schölderle
T
,
Pelykh
O
, et al.
How Does GPi-DBS Affect Speech in Primary Dystonia?
Brain Stimul
.
2015
Sep-Oct
;
8
(
5
):
875
80
.
[PubMed]
1935-861X
12.
Mure
H
,
Morigaki
R
,
Koizumi
H
,
Okita
S
,
Kawarai
T
,
Miyamoto
R
, et al.
Deep brain stimulation of the thalamic ventral lateral anterior nucleus for DYT6 dystonia
.
Stereotact Funct Neurosurg
.
2014
;
92
(
6
):
393
6
.
[PubMed]
1011-6125
14.
Hodgson
JC
,
Hudson
JM
. Chapter 6 - Speech lateralization and motor control. In: Forrester GS, Hopkins WD, Hudry K, Lindell A, editors. Progress in Brain Research [Internet]. Elsevier;
2018
. p. 145–78. (Cerebral Lateralization and Cognition: Evolutionary and Developmental Investigations of Behavioral Biases; vol. 238). Available from: http://www.sciencedirect.com/science/article/pii/S0079612318300542
15.
Buckner
RL
,
Raichle
ME
,
Petersen
SE
.
Dissociation of human prefrontal cortical areas across different speech production tasks and gender groups
.
J Neurophysiol
.
1995
Nov
;
74
(
5
):
2163
73
.
[PubMed]
0022-3077
16.
Pujol
J
,
Deus
J
,
Losilla
JM
,
Capdevila
A
.
Cerebral lateralization of language in normal left-handed people studied by functional MRI
.
Neurology
.
1999
Mar
;
52
(
5
):
1038
43
.
[PubMed]
0028-3878
17.
Springer
JA
,
Binder
JR
,
Hammeke
TA
,
Swanson
SJ
,
Frost
JA
,
Bellgowan
PS
, et al.
Language dominance in neurologically normal and epilepsy subjects: a functional MRI study
.
Brain
.
1999
Nov
;
122
(
Pt 11
):
2033
46
.
[PubMed]
0006-8950
18.
Tzourio
N
,
Crivello
F
,
Mellet
E
,
Nkanga-Ngila
B
,
Mazoyer
B
.
Functional anatomy of dominance for speech comprehension in left handers vs right handers
.
Neuroimage
.
1998
Jul
;
8
(
1
):
1
16
.
[PubMed]
1053-8119
19.
Peelle
JE
.
The hemispheric lateralization of speech processing depends on what “speech” is: a hierarchical perspective
.
[Internet]
.
Front Hum Neurosci
.
2012
Nov
;
6
:
309
. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3499798/
[PubMed]
1662-5161
20.
Hertz-Pannier
L
,
Chiron
C
,
Jambaqué
I
,
Renaux-Kieffer
V
,
Van de Moortele
PF
,
Delalande
O
, et al.
Late plasticity for language in a child’s non-dominant hemisphere: a pre- and post-surgery fMRI study
.
Brain
.
2002
Feb
;
125
(
Pt 2
):
361
72
.
[PubMed]
0006-8950
21.
Knecht
S
,
Dräger
B
,
Deppe
M
,
Bobe
L
,
Lohmann
H
,
Flöel
A
, et al.
Handedness and hemispheric language dominance in healthy humans
.
Brain
.
2000
Dec
;
123
(
Pt 12
):
2512
8
.
[PubMed]
0006-8950
22.
Möddel
G
,
Lineweaver
T
,
Schuele
SU
,
Reinholz
J
,
Loddenkemper
T
.
Atypical language lateralization in epilepsy patients
.
Epilepsia
.
2009
Jun
;
50
(
6
):
1505
16
.
[PubMed]
0013-9580
23.
Szaflarski
JP
,
Binder
JR
,
Possing
ET
,
McKiernan
KA
,
Ward
BD
,
Hammeke
TA
.
Language lateralization in left-handed and ambidextrous people: fMRI data
.
Neurology
.
2002
Jul
;
59
(
2
):
238
44
.
[PubMed]
0028-3878
24.
Vingerhoets
G
,
Alderweireldt
AS
,
Vandemaele
P
,
Cai
Q
,
Van der Haegen
L
,
Brysbaert
M
, et al.
Praxis and language are linked: evidence from co-lateralization in individuals with atypical language dominance
.
Cortex
.
2013
Jan
;
49
(
1
):
172
83
.
[PubMed]
0010-9452
25.
Hu
A
,
Hillel
A
,
Meyer
T
.
Factors Associated With Patient-perceived Hoarseness in Spasmodic Dysphonia Patients
.
J Voice
.
2016
Nov
;
30
(
6
):
769.e23
6
.
[PubMed]
0892-1997
26.
Braden
MN
,
Johns
MM
 3rd
,
Klein
AM
,
Delgaudio
JM
,
Gilman
M
,
Hapner
ER
.
Assessing the effectiveness of botulinum toxin injections for adductor spasmodic dysphonia: clinician and patient perception
.
J Voice
.
2010
Mar
;
24
(
2
):
242
9
.
[PubMed]
0892-1997
27.
Lyons
MK
,
Boucher
OK
,
Evidente
VGH
. Spasmodic Dysphonia and Thalamic Deep Brain Stimulation: Long-term Observations, Possible Neurophysiologic Mechanism and Comparison of Unilateral Versus Bilateral Stimulation.
2010
. (1:106).
28.
Cannito
MP
,
Buder
EH
,
Chorna
LB
,
Dressler
R
.
Acoustic Measures of Phonation during Connected Speech in Adductor Spasmodic Dysphonia
.
Otolaryngol Open Access.
2012
Jan
;
1
(
1
):
2
2
.
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.