PROSPECTIVE-STUDY OF PATIENTS SUBJECTIVE RESPONSES TO BOTULINUM TOXININJECTION FOR SPASMODIC DYSPHONIA

Adductor spasmodic dysphonia (SD) is a speech disorder resulting from involuntary contractions of the laryngeal muscles. Botulinum toxin (BT ) injection of the thyroarytenoid muscle is an effective, though tempo rary, treatment for most SD patients. Though there are reports of obje ctive improvements in voice quality, there are no large studies of pat ients' subjective responses to treatment over time. In the present stu dy, patients were given voice diaries to rate vocal spasms, hoarseness , breathiness, volume problems, and dysphagia before and after BT trea tment. Analysis of these diaries revealed that: (1) most side effects had resolved 4 to 6 weeks after injection, whereas vocal spasm relief persisted; (2) vocal spasm relief and severity of side effects peaked within 1 week; and (3) unilateral injections, though as effective in r elieving vocal spasms, caused less volume and swallowing problems than did bilateral injections.