Laryngeal dystonia causing inspiratory stridor in children with cerebral palsy

OBJECTIVE To present three cases of inspiratory stridor caused by laryngeal dystonia (LD) in children with cerebral palsy (CP), one of whom is being treated by periodic botulinum toxin type A (BTX) injection into a vocalis muscle, thereby avoiding tracheostomy. STUDY DESIGN Case series. RESULTS AND CONCLUSIONS Laryngeal dystonia was diagnosed in three children with CP who presented with inspiratory stridor associated with generalized dystonia, all of whom were thought previously to have had laryngomalacia. The inspiratory stridor was severe enough in one patient that a tracheostomy was planned. In common with the movement disorder of generalized dystonia, the inspiratory stridor caused by LD was present in our patients when they were awake, worse when they were excited or agitated, diminished when they were awake and calm, and absent when they were asleep. Although there is overlap between the symptoms of LD and laryngomalacia (and other structural causes of upper airway obstruction) in children with CP, structural causes result in inspiratory stridor that is often persistent when patients are awake and relaxed or when they are asleep. Fiberoptic laryngoscopy in an awake patient with LD reveals vocal cord adduction in inspiration causing inspiratory stridor in association with generalized dystonia. Baclofen and gabapentin used together relieved the inspiratory stridor and improved the generalized dystonia of two patients, confirming the clinical diagnosis of LD, but for the last 2 years the third patient (the one with the most severe inspiratory stridor) also has required a periodic BTX injection into a vocalis muscle (the major vocal cord adductor) to relieve her inspiratory stridor, alternating the side of injection. Her mother considers this is a small price to pay to avoid tracheostomy. This is the first report of LD causing inspiratory stridor in patients with CP and the first reported use of BTX injection into a vocalis muscle for relief of inspiratory stridor due to LD in a child.