Pre-Procedure Planning
Equipment
Botulinum toxin treatment of laryngeal dystonias involves the following:
-
Flexible fiberoptic laryngoscope with distal chip for a two-person approach or a rigid 70° telescope for a one-person approach [4]
-
C-mount camera
-
Video monitor for visualization
-
Curved Abraham canula for delivery of topical lidocaine and vocal fold palpation
-
Needles for percutaneous injection (1.5 inch and 23, 25, or 27 gauge)
-
Flexible fine-gauge injection needle for use with working channel in flexible laryngoscope
-
Electromyographic (EMG) device
Along with the botulinum toxin to be injected, an assortment of syringes and needles, topical and infiltration anesthesia, ground and reference electrodes, alcohol swabs, cotton pledgets, and orotracheal injection device (when necessary) may be needed. [4]
Patient Preparation
Anesthesia
Percutaneous electromyography (EMG)–guided botulinum toxin for laryngeal dystonia: Local anaesthesia is optional.
Percutaneous indirect laryngoscopy-guided botulinum toxin for laryngeal dystonia: The cricothyroid membrane is punctured for administration of local anesthesia, instilling approximately 3 mL of 4% lidocaine into the airway.
Positioning
The patient is positioned in semirecumbent position with the chin elevated and head extended.
Monitoring & Follow-up
Late Sequelae
Late sequelae of botulinum toxin treatment of laryngeal dystonia may include the following:
-
Denervation atrophy
-
Fibrosis
-
EMG changes
Side Effects
Side effects may include the following:
-
Breathy dysphonia
-
Hoarseness
-
Swallowing difficulties (including aspiration)
-
Pain
-
Flulike symptoms
Complications
Complications may include the following:
-
Dysphagia
-
Airway compromise
-
Generalized weakness
-
Mechanism of action of botulinum toxin.
-
Laryngeal electromyography recording during injection of botulinum toxin.
-
Needle inserted into the cricoarytenoid muscle for botulinum toxin injection.