Botulinum toxin has been used as an alternative to surgery to treat upper esophageal sphincter (UES) dysfunction. It is a neurotoxin that blocks neuromuscular transmission, thereby reducing the tone of the treated muscle. The neuromuscular blockage is temporary, and lasts from 2 to 6 months.
Several studies have described botulinum toxin in the treatment of dysphagia secondary to UES dysfunction of different aetiologies (stroke, Parkinson’s disease, amyotrophic lateral sclerosis (ALS), damage to the pharyngeal plexus secondary to surgery of the cervical area) with percutaneous and endoscopic injection routes.
We have seen that patients with absolute or relative hypertonia of the UES benefit most from this therapy. Before indicating the treatment, therefore, a manometric examination must be performed to select suitable patients.
Neuromuscular electrical stimulation (NMES) is a new therapy that has been used to strengthen certain muscle groups with preserved motor innervation. NMES has already been used in other fields of rehabilitation medicine to strengthen striated muscle tissue.
The treatment consists of applying electrical current pulses to the floor of the mouth muscles through a number of surface electrodes, thereby increasing the strength of these muscles and improving glottic closure (preventing tracheal aspiration).
The results obtained in a first study performed in our unit are encouraging, suggesting that NMES is a useful technique for patients with oropharyngeal dysphagia. Moreover, the treatment of these patients has enabled us to show that the therapy is well tolerated and has no adverse effects.
The photos in Figure 4 show the electrostimulation equipment (VitalStim®) used at our hospital and an example of electrode placement in one patient during a speech-language therapy session.