Blom E D, Singer M I, Hamaker R C
Arch Otolaryngol. 1985 Apr;111(4):211-2. doi: 10.1001/archotol.1985.00800060035001.
Previous investigations identified that insufflation of the esophagus may elicit reflex pharyngoesophageal closure, impeding airflow and subsequent voice production. A simplified method for esophageal insufflation consistently evaluates the capacity for alaryngeal speech acquisition. Although primarily a method for predicting tracheoesophageal speech, it may also be an important prognostic indicator for traditional esophageal speech development.