title: Laterality of bolus passage through the pharynx in patients with unilateral medullary infarction.
abstract: Laterality of bolus passage in the pharynx is often seen in patients with medullary infarction. We evaluated the dominant side of bolus passage in the pharynx and investigated the factors that cause the passage to dominantly occur on the affected side. Forty-one patients (35 men and 6 women, 64 ± 9 years) with unilateral medullary infarction participated in this study. Bolus passage of 4 mL of thick liquid was evaluated in 3 regions (oropharyngeal, thyropharyngeal, and cricopharyngeal) and classified into 4 patterns (dominantly on the unaffected side [UAS], on both sides without clear laterality [BS], dominantly on the affected side [AS], and nonpassage of the bolus [NP]) by videofluoroscopic examination of swallowing. The bolus passages were as follows: UAS, BS, and AS occurred in 2, 32, and 7 patients in the oropharyngeal region; UAS, BS, and AS occurred in 5, 20, and 16 patients in the thyropharyngeal region; and UAS, BS, AS, and NP occurred in 11, 9, 10, and 11 patients in the cricopharyngeal region, respectively. In the thyropharyngeal region, the proportion of patients in whom the swallowing reflex occurred when the bolus was in the oropharynx and the proportion of patients with unilateral pharyngeal constrictor paralysis were greater in patients whose bolus passage was AS than in patients whose passage was BS. This suggests that the bolus predominantly passed through the affected side of the thyropharyngeal portion because of the asymmetry of pharyngeal contraction during swallowing in the early period after onset.
authors.affiliation: Department of Rehabilitation Medicine I, School of Medicine, Fujita Health University, Aichi, Japan; Department of Gerodontology, Division of Gerontology and Gerodontology, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan. Electronic address: yanngerd@tmd.ac.jp.
authors.forename: Shinya
authors.initials: S
authors.lastname: Mikushi
authors.affiliation: Department of Rehabilitation Medicine I, School of Medicine, Fujita Health University, Aichi, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kagaya
authors.affiliation: Department of Rehabilitation Medicine I, School of Medicine, Fujita Health University, Aichi, Japan.
authors.forename: Mikoto
authors.initials: M
authors.lastname: Baba
authors.affiliation: Department of Dysphagia Rehabilitation, Nihon University School of Dentistry, Tokyo, Japan.
authors.forename: Haruka
authors.initials: H
authors.lastname: Tohara
authors.affiliation: Department of Rehabilitation Medicine I, School of Medicine, Fujita Health University, Aichi, Japan.
authors.forename: Eiichi
authors.initials: E
authors.lastname: Saitoh
mesh_terms: D000328:Adult; D000368:Aged; D020526:Brain Stem Infarctions / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D003679:Deglutition; D003680:Deglutition Disorders / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D005471:Fluoroscopy; D007839:Functional Laterality; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008526:Medulla Oblongata / Q000503:physiopathology*; D008875:Middle Aged; D010614:Pharynx / Q000000981:diagnostic imaging / Q000294:innervation*; D012018:Reflex; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014741:Video Recording
keywords: Deglutition; bolus passage; deglutition disorders; medullary infarction; videofluoroscopic examination of swallowing