It is hypothesized that there is no difference in the effectiveness of botulinum toxin (BTX) injection between electromyography (EMG)-guided and non–EMG guided “point-touch” techniques in the treatment of adductor spasmodic dysphonia.
Retrospective chart review.
Patients selected for evaluation underwent sequential treatment by one or both of the senior authors using two different injection techniques with similar BTX dilution and preparation. Data gathered included dose injected, injection effect, and presence and duration of breathiness and dysphagia after injection. Statistical analysis was performed used a generalized estimating equations model.
A total of 417 injections in 64 patients were analyzed. There was no difference in the rate of successful injections between the EMG-guidance group and the non–EMG guidance group (94.4% and 93.2%, respectively; P = .7).
This unique study demonstrates that efficacy of BTX does not necessarily depend on the method of injection used. In experienced hands, excellent clinical results can be achieved with either EMG-guided or non–EMG guided injection techniques.