A single-centre retrospective review of unilateral and bilateral Dysport injections in adductor spasmodic dysphonia.

We reviewed the results and side-effect profile of the Dysport preparation of botulinum toxin A (BTA) in the management of the adductor spasmodic dysphonia. We performed 272 injection episodes in 68 patients, 42 (62%) female, 26 (38%) male. A total of 116 of these injections were unilateral, and 156 were bilateral; 94% of the injections were considered to have been successful with a voice score of 2 or higher. The mean duration of effect (injection intervals) was 128.8 days in the unilateral cohort and 118.7 days in the bilateral (P > 0.05). We injected a relatively lower dose of BTA for unilateral injection episodes in our institution compared to those reported by others to produce comparable results and side-effect profiles.