Bolus Location at the Initiation of the Pharyngeal Stage of Swallowing in Healthy Older Adults

Abstract

This study characterized the vertical position of the bolus head at the onset of the pharyngeal swallow in healthy older adults. Lateral-view videofluoroscopic (VF) images were obtained from ten healthy volunteers (age-71.6 +/- 7.5 years, mean+/- SD) as they swallowed 5-cc thin liquid barium aliquots. For each swallow, the bolus head and several anatomic landmarks were digitally recorded from the image in which pharyngeal swallow-related hyoid bone elevation began. Vertical distance between the bolus head and the intersection of the tongue base and mandibular ramus (TMI) was computed. Bolus head position at swallow onset ranged from 47.4-mm above to 34.9-mm below the TMI (2.2 +/- 14.4-mm, mean +/- SD). Although the bolus head was below the level of the TMI for the majority of swallows, neither penetration nor aspiration occurred. For individual subjects, mean bolus head position ranged from 25.8 +/- 5.0-mm above to 15.5 +/- 6.5-mm below the TMI. Whereas five of ten subjects initiated the pharyngeal swallow with the bolus head consistently above or consistently below the TMI, five subjects initiated swallowing with the bolus head either above or below the TMI across trials. Older adults commonly initiate thin-liquid swallows with the bolus head well below the TMI without associated penetration or aspiration. Thus, bolus position alone does not differentiate between normal and pathologic swallowing within the healthy elderly. Bolus position at pharyngeal swallow onset can vary substantially from trial to trial within an individual, suggesting that the triggering of swallowing depends on multiple influences.

Efeitos do exercício muscular respiratório na biomecânica da deglutição de indivíduos normais

“…However, the identification of a reference to the location of the pharyngeal phase firing is still an object of study, beyond the time of its phases. The study of temporal measures, through objective data, does not present a consensus about their reference values [18][19][20] yet, ranging from 0.7 to 1.0 second 21 . Vale-Prodomo 22 verified that the time of the mean time of the pharyngeal phase is 0.71 seconds.…”

Locais de início da fase faríngea da deglutição: meta-análise

“…In seven studies, individuals below the age of 60 in the sample accounted for 59% (178 individuals) of the total (2,6,7,12,16,17,22) . Above this age group, only 69 individuals were described in three different studies (8,18,19) .…”

“…Seven studies consisted of an asymptomatic population, making up 57% (170 individuals) of the total investigated (2,6,7,12,16,17,20) . These individuals did not have any swallowing complaint or comorbidities that were known to influence swallowing dynamics.…”

“…The volume of 5 ml was the most used (five articles), also in other consistencies (2,12,16,18,20) . In the other studies, the consistencies and volumes varied among them, as there was no standardization and therefore difficult to perform analysis between the consistency and the location of the onset of the pharyngeal phase of swallowing.…”

“…The fluidsensitive receptors, according to the author, are located in the paraepiglottic channels. Nonetheless, it has been observed in some studies (6,12) , in which individuals considered asymptomatic, namely, those who do not have underlying diseases and/or clinical characteristics, may present the onset of the pharyngeal phase of swallowing elsewhere in the oropharyngeal tract without physiopathologic implications that indicate risk for laryngeal penetration or aspiration.…”