Botulinum toxin treatment for spasmodic dysphonia: percutaneous versus transoral approach

Spasmodic dysphonia (SD) is at present defined as focal dystonia. Botulinum toxin (BT) injection is the treatment of choice for SD. BT is usually injected by a percutaneous route, but a direct, visually guided transoral approach has also been successful. It is not known whether percutaneous injection is as effective as the transoral approach. This article reviews our experience with both techniques of injection on 29 patients with adductor type SD. Since 1992, we have carried out 48 treatment sessions with the transoral technique and 76 treatment sessions with the percutaneous technique. Two patients did not respond to the percutaneous technique despite several attempts, but they did respond to the transoral approach. Globally, transoral technique was superior to percutaneous technique in terms of effectiveness (48 of 48 responses with transoral technique versus 61 of 76 responses with percutaneous approach, p < 0.01). Dosage of BT, duration, and side effects were similar with both techniques. This article also describes a simple, inexpensive device, composed of materials on hand at every hospital, that facilitates the transoral approach.