An EMG screening method (dysphagia limit) for evaluation of neurogenic dysphagia in childhood above 5 years old

Oropharyngeal dysphagia is not rare in older children before the adult age, especially the patients with cerebral palsy. Non-invasive simple tests are needed for the evaluation of children with neurogenic dysphagia including the patients with cerebral palsy. So we aimed to evaluate non-invasive ways to screen for dysphagia in children and the usefulness of this almost new electrophysiologic method for the detection of dysphagia in children with cerebral palsy. Twenty-eight healthy children and 12 patients with cerebral palsy were investigated for the applicability of this method. The movement of the larynx was monitored using a simple piezoelectric wafer sensor and submental surface EMG activity was recorded by bipolar silver-chloride electrodes taped under the chin over the submental muscle complex. The onset and duration of pharyngeal swallowing was recorded from submental-suprahyoid muscles such as the mylohyoid-genitohyoid-anterior digastric complex. By this method, the maximal water volume capacity was measured in single swallows with progressively increasing water volumes, this was called 'dysphagia limit'. The healthy control children revealed to swallow the bolus at once maximally 11.2+/-0.4 and 2.5 ml in average. Dysphagia limit varied from 7 to above 20 ml water volume from age 5-16 years old. Patients with cerebral palsy had the dysphagia limit of 7.7+/-1.8 and 6.4 ml in average. The dysphagia limit was significantly reduced in patients with cerebral palsy (p<0.05). Dysphagia limit seemed to be less sensitive in demonstrating the oropharyngeal swallowing disorders in childhood period (90% in the adult dysphagic patients). But the majority of patients with cerebral palsy (58%) showed abnormality. This electrophysiologic method is completely non-invasive, devoid from any hazard and applicable to children above 5 years. It may be candidate as a screening test before selection of dysphagic children.