title: Prediction of dysphagia severity: an investigation of the dysphagia patterns in patients with lateral medullary infarction.
abstract: OBJECTIVE
  In order to identify the factors that influence the swallowing function in patients who develop Wallenberg syndrome (WS) following lateral medullary infarction (LMI), we examined various patient characteristics, including the passage pattern abnormality (PPA) of a bolus through the upper esophageal sphincter (UES).
  
  
  METHODS
  Fifty-four pure LMI patients with dysphagia participated in this study. PPA, defined as the failure of bolus passage through the UES corresponding to the intact side of the medulla, was identified during videofluorographic swallowing evaluations of each patient. On brain magnetic resonance imaging, the subjects' lesions were classified vertically into three levels and horizontally into seven levels in relation to the involvement of the ambiguous and/or solitary nuclei. Logistic regression analyses were performed for age, sex, PPA and the vertical and horizontal sites of the lesions.
  
  
  RESULTS
  In terms of severity, 15 subjects were categorized as having mild dysphagia, 26 subjects were categorized as having moderate dysphagia and 13 were categorized as having severe dysphagia. Subjects with cephalic lesions, greater vertical spread of the lesion and PPA were more likely to have severe dysphagia. PPA and a greater vertical spread of the lesion were related to the severity of the functional outcome (p<0.01). The horizontal extent of the lesion was not strongly related to the prognosis.
  
  
  CONCLUSIONS
  The presence of PPA in LMI patients is suggestive of abnormalities in the swallowing pattern and, in turn, damage to the medullary central pattern generator. The presence of PPA and a greater vertical spread of the lesion can be useful predictors of severe dysphagia.
authors.affiliation: Department of Neurology, Japanese Red Cross Kyoto Daiichi Hospital, Japan. oshima-fumiko@kyoto1-jrc.org
authors.forename: Fumiko
authors.initials: F
authors.lastname: Oshima
authors.forename: Megumi
authors.initials: M
authors.lastname: Yokozeki
authors.forename: Masashi
authors.initials: M
authors.lastname: Hamanaka
authors.forename: Keisuke
authors.initials: K
authors.lastname: Imai
authors.forename: Masahiro
authors.initials: M
authors.lastname: Makino
authors.forename: Miyuki
authors.initials: M
authors.lastname: Kimura
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Fujimoto
authors.forename: Masako
authors.initials: M
authors.lastname: Fujiu-Kurachi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003679:Deglutition / Q000502:physiology; D003680:Deglutition Disorders / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D014854:Lateral Medullary Syndrome / Q000150:complications* / Q000473:pathology / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D014741:Video Recording