2009 Volume 13 Issue 3 Pages 165-175
[Objective] The purpose of this study was to distinguish patients with hysterical swallowing difficulty (HSD) from those with dysphagia due to neuromuscular diseases (NMD) by videofluorography (VF).
[Subjects and Methods] Sixteen patients who described difficulty in propelling foods from the oral cavity to the pharynx, but had no organic abnormalities on neurologic examination or imaging, were diagnosed with HSD. For comparison, 30 healthy individuals (normal controls, NC), 30 patients with amyotrophic lateral sclerosis (ALS), 30 patients with muscular diseases (MD), and 30 patients with Parkinson's disease (PD) were enrolled. In all individuals, VF was performed while drinking 10 ml of liquid barium (liquid) and while eating 8 g of corned beef hash with barium paste (CB). VF characteristics were compared among the groups (Mann-Whitney U test and correspondence analysis).
[Results] In the HSD group, the anteroposterior diameter of the pharynx was similar to that in the NC and PD groups, but it was shorter than that in the ALS and MD groups. With liquid, the swallowing reflex was often initiated on the oral side for the HSD and NC groups. Aspiration of liquid was seen in 16.7–20.0% of the NMD patients but in none of the HSD or NC patients. Five patients with HSD showed several interruptions of liquid propulsion from the oral cavity to the pharynx after the start of swallowing. We named this finding “intermittent interruption of food propulsion.” Few individuals in the other groups showed this finding. With CB, three patients with HSD could not swallow the bolus. The number of chews in the HSD group was similar to that in the NC, ALS, and PD groups. The swallowing reflex was often initiated on the oral side for the HSD group; therefore stage II transport was infrequently initiated during chewing. Pharyngeal residue after either eating CB or drinking liquid was rare in the HSD and NC groups.
[Conclusions] The HSD group resembled the NC group in terms of the position of liquid at the start of the swallowing reflex and the pharyngeal residue after swallowing. Dilatation of the pharynx and liquid aspiration were useful findings to differentiate NMD patients from HSD patients. Intermittent interruption of food propulsion and lack of stage II transport during chewing were characteristic findings for the HSD patients.