Conclusions and Inferences: Patients who have undergone UPPP and/or CCT surgery appear to have a deficit in normal modulation of the swallowing mechanism and impaired swallowing. In oropharyngeal surgery patients, swallowing reserve is reduced due to reduced sensory modulation of the swallowing response to volume problems. Uvulopalatopharyngoplasty with Coblation Channeling of the Tongue (UPPP+CCT) is used to treat obstructive sleep apnea syndrome (OSAS) 1.
Surgery is typically performed in middle-aged patients, and there is a possibility that mild deglutitive dysfunction may become important later in life, due to deterioration of the swallowing mechanism 6, 7, 8. Afferent modulation of the swallowing motor mechanism enables an appropriate swallowing response adapted to the characteristics of the bolus. Eight of the patients had a primary diagnosis of OSAS based on excessive sleepiness, defined by an Epworth Sleepiness Scale (ESS) score >1015 and a severe apnea hypopnea index (AHI ≥ 30/h) recorded during a polysomnography16.
Of the remainder, three patients had primary snoring and one reported globus sensation and was included in this case series because of reported significant dysphagia symptoms after CCT. The SSQ scores of the patient cohort were compared with data from normal cohort of 73 asymptomatic individuals (established by Author MMS18). After landmark selection, the pressure-impedance profiles of the hypopharynx and UES were plotted and data for 14 swallowing function measures were calculated.
Ten of the 11 patients completed HRIM assessment with the full bolus protocol (3-5 repetitions 5, 10 and 20 ml volume of thin and thick consistency), while 1 patient, who SSQ 933 and significant vallecular residue (solid NRRSv 0.28 ) had, was unable to swallow 20ml thick boluses. Thicker bolus consistency did not change lumen occlusive pressure except proximal esophageal contractility (PCI), which was higher for thick bolus. In addition, we observed a reduced neutrally mediated pre-deglutitive tone of the UES (UES BP, Table 2).
This may be a result of reduced UES orifice compliance, secondary to long-term upper airway obstruction and/or CPAP use, or the result of sensory dysregulation of the swallowing mechanism, due to loss of sensory afferent input13, 14, 22. That is, the ability of the pharyngeal constrictors to bring the lumen to a point of occlusion and then generate post-occlusive pressure may be reduced, especially during conditions of high flow resistance such as those associated with the thickest consistencies. Most of the patients received the oropharyngeal surgery for treatment of severe OSAS, a clinical syndrome affecting at least 2-4% of the adult population28 and confirmed on the basis of polysomnography during sleep16, 29.
Patients with OSAS can be young; therefore, the influence of the aging process must be taken into account. The development of the Swallow Gateway website and the web analytics portal AIMplot was supported by a grant from Flinders University's Faculty of Health Sciences. Potential Competing Interests: Omari has an inventive family of patents covering the analytical methods described.
Surgical modifications of upper respiratory tracts for obstructive sleep apnea in adults: a systematic review and meta-analysis.
Supplementary Tables
Main and interaction effects of group and bolus thickness on swallowing function variables. Variables showing no effects were omitted, they were; VTBI, BPT, UESCI and UES Peak P. Corresponding swallows were selected from the pressure topography map by drawing regions of interest (ROIs) from the velopharynx to the esophageal transition zone.
The selected swallows could then be viewed on an expanded pressure topography plot and analyzed individually by manual placement of the six landmarks; in order were these; 1.UES opening point and 2.UES closing point and the positions of 3.velopharyngeal proximal margin, 4.hypopharyngeal proximal margin, 5.UES apogee and 6.UES distal margin. Hypopharyngeal and UES pressure and access time profiles are shown in subplots below the pressure topography plot. The axial pressure profile along the pharynx at the time of maximum UES opening is shown in the subplot to the right of the main plot.
After the course was set, the landmarks were fine-tuned, such as to align the UES opening point with the UES inlet stroke and the UES closing point with the UES pressure up stroke. The Swallow function variables were automatically generated and displayed for the swallow (see 'Swallow Properties'; . bottom left). These were defined as follows (see also Supplementary Table 1): Intra-bolus hypopharyngeal pressure (IBP), the discrete pressure value recorded at 1 cm above the apogee of the UES at the time point of maximum intake (maximum bolus distension); .
Mean peak pharyngeal pressure (Peak P), the mean maximum contractile pressure recorded for the pharyngeal stripping wave. UES Open Time (UES Open T), the time from open to close point set for the UES. UES maximum admittance (UES Max Adm), the maximum admittance reading recorded within the UES region during UES opening.
All contractile/pressure integrals were determined by the mean pressure within the respective domain multiplied by the duration and range, that is; Tongue base velopharyngeal pressure integral (VTBI), hypopharyngeal contractile integral (HPCI), UES contractile integral (UESCI) and proximal esophageal contractile integral (PCI). The lines are square and whisker curves, *proves that two questions reached statistical significance according to Šidák's whisker curve, *proves that two questions reached statistical significance according to Šidák's correction for multiple tests (p<0.0012): Q16, How do you rate the severity of your swallowing problem today. The blue horizontal line defines the period from the initial opening of the UES (O) to the closing of the UES (C), point "a." and the position of the apogee of the UES is at the time of the maximum opening of the UES (defined by the admittance peak).
The three plots are temporarily aligned with the UES closing time; Note that the timing of the initial UES opening and the maximum UES opening occurs earlier and earlier, with increasing volume leading to a longer total period of UES opening. Pharyngeal axial pressure profiles at the time of maximum UES opening for the three swallow volumes ('a.' in each pressure topography plot); note that the expansion pressure.
