The Otolaryngologic Uses of Botox Malcolm Baxter FRACS
Botox Clostridium botulinum toxin 7 Serotypes -ABCDEFG Type A used Botox (Allergan) Dysport Neurotoxin-paralyses neuromuscular transmission by binding ACh Mouse units
Botox cont. Now widely used for muscle spasms and spasticity: Laryngeal Conditions Blepharospasm Hemifacial Spasm Spasmodic Torticollis Palatal Myoclonus Frey’s Syndrome Failed TOP Speech Post Laryngectomy Drooling (intraparotid ) Achalasia Cerebral Palsy Patient Limbs Cosmetic
Laryngologic Uses of Botox Spasmodic Dysphonia-Adductor &Abductor Types Laryngeal Tremor Muscle Tension Dysphonia –unresponsive to SP and local physio techniques Refractory Laryngeal Granulomata Cricopharyngeal Spasm –intact larynx and post-laryngectomy CA Joint Dislocation/Relocation Vocal Cord Dysfunction (PVFM)
Botox cont. Side Effects Effects of overweakening-depends on location Abs produced-Anaphylaxis theoretically possible but not in practice ? No Deaths
Laryngeal Botox for SD in Melbourne RVEEH 1992-2008 Baxter,Hughes & Oates Continues as private clinics MMC Monash Neurolaryngology Clinic 2010- Baxter & Raghav
SPASMODIC DYSPHONIA Action induced laryngeal motion disorder resulting in a dysphonia characterised by spasms in phonation
Spasmodic Dysphonia Classified as Focal Dystonia (class of movement disorder) These are task specific movement disorders involving a few muscles (laryngeal in this case) Other examples are: Spasmodic Torticollis, Writers Cramp, Hemifacial Spasm, Blepharospasm, Meige’s syndrome-orofacial dystonia
Aetiology of SD Unknown Genetic Probable in some cases ??Stress ??Infective PM Studies-unhelpful with varying findings, eg basal ganglia
ABDuctor SD <10% -breathy interruptions to fluency (PCA) SD-2 Types ADDuctor SD >90% -strained and strangled voice due to spasmodic interruptions to fluency (Thyroarytenoid-vocalis) ABDuctor SD <10% -breathy interruptions to fluency (PCA)
Spasmodic Dysphonia F>M about 2:1 Onset any age (Satalhoff ave 62) Many patients relate to some traumatic or stressful event
Diagnosis of SD Typical Phonation Demonstrated Spasms on Video during connected speech Lack of response to other treatment (espec. ST) EMG ?? Must exclude other neurological disease
Differential Diagnosis Laryngeal Tremor Severe Hyperfunctional or Muscle Tension Dysphonia Psychogenic Dysphonia
Treatment of SD Psychiatric Drugs Speech Therapy Surgery BOTOX
Botox in SD Transoral Concious pt / GA Transcutaneous with EMG Control Monopolar Teflon coated EMG neeedle connected to EMG machine GA -occasionally
Botox in SD cont Adductor - via CT membrane intoThyroarytenoid/ vocalis -2.5 Mu per vocal cord starting dose (titrate response) Abductor - Into PCA -More difficult -Lateral or translaryngeal approach - 3.75 Mu starting (titrated) -Unilateral Injection -May assess weakness by scope Rating??
Method Prospective study Botox injections for adductor and abductor spasmodic dysphonia between 1992 and 2003 Assessment and diagnosis by otolaryngologist, neurologist and speech pathologist in voice clinic
Method Pre and post-injection self evaluation of voice function on equal appearing interval scale 1 to 10 1= severe disabling voice problem, 10= no perceived voice problem Complications (mild/ moderate/ severe) Breathiness Dysphagia Pain bruising
Method Pre and post-injection self evaluation of voice function on equal appearing interval scale 1 to 10 1= severe disabling voice problem, 10= no perceived voice problem Complications (mild/ moderate/ severe) Breathiness Dysphagia Pain bruising
Injection Method Transcutaneous submucosal injection through cricothyroid membrane with EMG control few injections required transoral and translaryngeal technique Adductor patients- injection into thyroarytenoid muscle Abductor patients- injection into posterior cricoarytenoid muscle
Results Consecutive series of 81 patients, complete information available in 79 511 injections of Botox 59 female, 20 male
Adductor Group 72 patients, 481 injections Bilateral injections in 96% (464 injections), unilateral 4% (17 injections) Median dose 2.5 mouse units (range 0.5-5)
Adductor Group 95% of injections (459) improvement in symptoms Median improvement 4 points (range 1-8) Mean duration of response 15.3 weeks (range 0.5-72)
Adductor group 72% complications (346 injections) Breathiness (317), 68% mild, median duration 2 wks Dysphagia- (110) 86% mild, median duration 2 wks Pain (12) Bruising (4)
Abductor group 7 patients, 30 injections 2 bilateral injection, 28 unilateral median dose 4.5 (range 2.5 to 6.25)
Abductor group 60% injections (18) symptom improvement Median improvement 3 points ( range 1-5) Mean duration response 11.4 weeks (range 4-20)
Conclusions Laryngeal botox injections results in significant, sustained voice improvements in adductor spasmodic dysphonia Side effects are frequent but majority are mild in severity Results in abductor spasmodic dysphonia less favourable
Can we extrapolate to VCD?
Vocal Cord Dysfunction (VCD) Various names-Paradoxical Vocal Cord Movement (PVFM ) probably best Adduction of VCs during inspiration Various types Dystonia Asthma associated (? >10% ED ‘asthma” presentations (?? All have asthma) Exercise induced Psychological LPR—Acute laryngeal spasms-? different
Diagnosis of VCD History Flexible Scope 360 Slice CT Stridor Not responding to asthma meds Exercise induced Psych ?? Flexible Scope 360 Slice CT
Treatment of VCD Breathing Exercises (SP) Effective ~80% Medication – Asthma meds,Diazepam etc PPIs often effective for the Laryngospasm Botox –Anecdotal evidence , Awaiting RCT