Unilateral versus bilateral thyroarytenoid Botulinum toxin injections in adductor spasmodic dysphonia: a prospective study.
OBJECTIVE
In this preliminary prospective study, we compared unilateral and bilateral thyroarytenoid muscle injections of Botulinum toxin (Dysport) in 31 patients with adductor spasmodic dysphonia, who had undergone more than 5 consecutive Dysport injections (either unilateral or bilateral) and had completed 5 concomitant self-rated efficacy and complication scores questionnaires related to the previous injections. We also developed a Neurophysiological Scoring (NPS) system which has utility in the treatment administration.


METHODS
Data were gathered prospectively on voice improvement (self-rated 6 point scale), length of response and duration of complications (breathiness, cough, dysphagia and total voice loss). Injections were performed under electromyography (EMG) guidance. NPS scale was used to describe the EMG response. Dose and unilateral/bilateral injections were determined by clinical judgment based on previous response. Time intervals between injections were patient driven.


RESULTS
Low dose unilateral Dysport injection was associated with no significant difference in the patient's outcome in terms of duration of action, voice score (VS) and complication rate when compared to bilateral injections. Unilateral injections were not associated with any post treatment total voice loss unlike the bilateral injections.


CONCLUSIONS
Unilateral low dose Dysport injections are recommended in the treatment of adductor spasmodic dysphonia.
Upile
Tahwinder
T
The Royal National Throat, Nose and Ear Hospital, London, UK. mrtupile@yahoo.com
Elmiyeh
Behrad
B
Jerjes
Waseem
W
Prasad
Vyas
V
Kafas
Panagiotis
P
Abiola
Jesuloba
J
Youl
Bryan
B
Epstein
Ruth
R
Hopper
Colin
C
Sudhoff
Holger
H
Rubin
John
J
D000704:Analysis of Variance; D001905:Botulinum Toxins / Q000008:administration & dosage*; D004576:Electromyography; D005260:Female; D006801:Humans; D007273:Injections, Intramuscular / Q000379:methods; D008297:Male; D008875:Middle Aged; D009465:Neuromuscular Agents / Q000008:administration & dosage*; D010699:Phonation; D011446:Prospective Studies; D012720:Severity of Illness Index; D013035:Spasm / Q000188:drug therapy* / Q000503:physiopathology; D014832:Voice Disorders / Q000188:drug therapy* / Q000503:physiopathology; D014833:Voice Quality
D009465:Neuromuscular Agents; D001905:Botulinum Toxins