title: Botulinum Toxin in Secondarily Nonresponsive Patients with Spasmodic Dysphonia.
abstract: Chemodenervation with botulinum toxin (BoNT) has been effective and well tolerated for all types of dystonia for >30 years. We reviewed outcomes of our patients treated with BoNT serotype A (BoNT-A) for spasmodic dysphonia (SD) who became secondarily nonresponsive. We found that 8 of 1400 patients became nonresponsive to BoNT-A (0.57%), which is lower than the secondary nonresponse rate in other dystonias. After a cessation period, 4 of our patients resumed BoNT-A injections, and recurrence of immunoresistance was not seen in any of them. When compared with patients with other dystonias, patients with SD receive extremely low doses of BoNT. Small antigen challenge may explain the lower rate of immunoresistance and long-lasting efficacy after BoNT-A is restarted among secondary nonresponsive patients with SD.
authors.affiliation: Voice and Swallowing Disorders, Division of Otolaryngology-Head and Neck Surgery, Maimonides Medical Center, Brooklyn, New York, USA Department of Otolaryngology-Head and Neck Surgery, Mount Sinai Roosevelt Hospital, New York, New York, USA nivmor73@gmail.com.
authors.forename: Niv
authors.initials: N
authors.lastname: Mor
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Mount Sinai Roosevelt Hospital, New York, New York, USA Department of Head and Neck Surgery, Kaiser Permanente Medical Center San Francisco, San Francisco, California, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Tang
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Mount Sinai Roosevelt Hospital, New York, New York, USA NY Center for Voice and Swallowing Disorders, New York, New York, USA Department of Neurology, Ichan School of Medicine at Mount Sinai, New York, New York, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Blitzer
mesh_terms: D019274:Botulinum Toxins, Type A / Q000008:administration & dosage / Q000627:therapeutic use*; D055154:Dysphonia / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008297:Male; D009465:Neuromuscular Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A; C545476:incobotulinumtoxinA
keywords: Botox; botulinum toxin; immunoresistance; onabotulinumtoxinA; secondary nonresponse; spasmodic dysphonia