• Objective: To provide an evidence-based clinical update on the pathophysiology, assessment, and treatment of spasmodic dysphonia (SD). • Methods: We reviewed the extant literature on SD spanning predominantly the past 2 decades. References were extracted from Medline and PubMed using search terms of spasmodic dysphonia, pathophysiology, assessment, and treatment since 1990. • Results: Whereas technological advances have clearly defined SD as a neurologically based disorder with possible genetic and environmental links, specific neurologic underpinnings remain elusive. Best practice continues to be treatment via botulinum toxin injection, though results are significantly better for adductor than abductor type SD. Surgical interventions are being reported with increasing success. • Conclusions: Research should examine long-term outcomes in botulinum toxin versus surgical intervention and continue to define the neurologic substrates of SD. Copyright 2013 by Turner White Communications Inc., Wayne, PA. All rights reserved.
