Tubomanometry in measurement of velopharyngeal closure: A pilot study

Abstract

Objective: To investigate the differences in velum closure pattern in people with and without a history of middle ear disease using intranasal pressure curves recorded with the tubomanometer, a Eustachian tube (ET) testing device.

Study design: Case control study.

Setting: Tertiary referral center.

Subjects and methods: Tubomanometry nasopharyngeal pressure curves from 20 controls (Group 1) and 20 people with history of otitis media (OM) and possible ongoing ET dysfunction (ETD) (Group 2 or OM/ETD group) were compared. The variables included in the analysis were: (a) ratio of signal amplitude relative to the delivered nasal pressure (C2/delivered pressure x 10); (b) time (s) to achieve maximal signal amplitude (C2-C1); (c) duration of velum closure (s) and (d) plateau decay during the isometric contraction of the velum (C3-C2) and (e) swallow duration (s) (C4-C1). Statistical analysis was conducted using mixed models for the normalized values of individual characteristics.

Results: Age, race and sex distribution in each group was as follows: 24 ± 8 years, 15 whites and 12 females in Group 1; 20 ± 10 years, 19 whites and 15 females in Group 2. Group 2 demonstrated a greater velopharyngeal pressure decay (p = .13), longer swallow duration (p = .10), and longer duration of velum closure (p = .14).

Conclusion: This is the first study using tubomanometry to investigate differences in velopharyngeal closure between controls and individuals with OM/ETD. Although not statistically significant, our results showed that those with OM/ETD demonstrated a longer swallow and velum closure duration, and a higher degree of leakage during velum contraction compared to controls.

Keywords: Eustachian tube; otitis media; tubomanometry; velopharyngeal closure; velopharynx.

FIGURE 1

Graphic representations of the nasopharyngeal (bottom) and ear (upper) pressure curves generated by the tubomanometer software (A) and Lab Chart (B). C1, C2, C3, and C4 are the reference points for the changes in nasopharyngeal pressure (Y axis) over a period of time (X axis). As shown in Figure B, surface EMG (green line), allowed precise timing of each swallow

FIGURE 2

Average tubomanometry curves that represent the nasopharyngeal (NP) pressure during the testing for Group 1 (controls—solid line) and Group 2 (OM/ETD participants—dashed line) when the tubomanometer maximum pressure is set at 30, 40, and 50 mbar. The asterisk represents the abrupt change in direction of the C1‐C2 slope caused by the secondary bolus of air released by the tubomanometer. This point was called trigger or “T” point and is represented by an asterisk. Y axis = change in pressure (mmH₂O), X axis = duration of the event (s)

FIGURE 3

Distribution of time (s) to achieve maximal amplitude (figure on the left) and ratio of signal amplitude (the actual pressure achieved) to source pressure (figure on the right) at 30, 40, and 50 mbar for Group 1 (controls) and Group 2 (OM/ETD participants)

FIGURE 4

Distribution of pressure decay during velopharyngeal closure (amount of change in the NP pressure between C2 and C3) at 30, 40, and 50 mbar for Group 1 (controls) and Group 2 (OM/ETD participants)

FIGURE 5

Distribution of swallow duration (figure on the left) and velopharyngeal closure duration (s) (figure on the right) at 30, 40, and 50 mbar for Group 1 (controls) and Group 2 (OM/ETD participants). Both the durations of swallow and velar closure are longer in the participants with the history of OM/ETD (Group 2)