UPPER AIRWAY SIZE AND COLLAPSIBILITY IN SNORERS - EVALUATION WITH DIGITAL FLUOROSCOPY

This study addressed the question of whether there are any differences in the size and collapsibility of the upper airway measured by digita l fluoroscopy, between snorers and controls whilst they were awake and breathing normally; and whether there are any correlations between th ese measurements and other clinical data. The dynamic changes of the u pper airway size were evaluated using digital fluoroscopy in 33 patien ts and 16 normal controls, The measurements were compared with finding s in an overnight sleep study, including a static-charge-sensitive bed (SCSB) and oximeter recordings. The minimum anteroposterior dimension at the velopharyngeal level was smaller in patients with partial uppe r airway obstruction than in controls (p<0.005); patients with complet e obstruction did not differ from the controls, The velopharyngeal air ways were also more collapsible in patients with severe partial obstru ction (p<0.01) than in controls, At the oropharyngeal and hypopharynge al levels, the dimensions and the collapsibilities were similar in pat ients and controls, The velopharyngeal collapsibility correlated with body mass index (p<0.001), whereas the airway size did not, The veloph aryngeal collapsibility was more pronounced in patients with frequent episodes of arterial oxyhaemoglobin desaturation during sleep. Velopha ryngeal collapsibility associated with high body mass index was the im portant determinant of nocturnal breathing disturbances. Digital fluor oscopy displays the dynamic changes of the upper airways throughout th e respiratory cycle.