Electromyography of cricopharyngeal muscles in patients with oesophageal speech.
Subject for the examination were 30 patients who during total laryngectomy had had two silver clips for haemostasis inserted into the cricopharyngeous muscle about 3 cm from the sewing place in the midline, facilitating the location of the muscle and the placing of a needle electrode. Twelve to 18 months after laryngectomy and phoniatric rehabilitation, electromyographic examinations were performed. Each EMG recording was evaluated as to amplitude, discharge frequency and time duration of muscle electric activity. EMG recordings made during deglutition and phonation proved dependences of cricopharyngeous muscle activity on quality of oesophageal voice production and higher activity of muscle during phonation than deglutition in patients who developed very good and good oesophageal speech.