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 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 postlaryngectomy • CA Joint Dislocation/Relocation • Vocal Cord Dysfunction (PVFM)

Botox cont. Side 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

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 into. Thyroarytenoid/ 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

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. 572)

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 – 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