Volume estimation of the preepiglottic and paraglottic space using spiral computed tomography

The purpose of this study was to estimate the volume variability of the preepiglottic and paraglottic space in the normal larynx. In 23 adult patients (12 women, 11 men), a spiral CT acquisition through the larynx was obtained. No laryngeal pathology was observed. The area of the this submucosal fat space was estimated on each slice by semi-automatic segmentation; the volume was calculated by the summation-of-areas technique. The obtained volumes were correlated with body area, body mass index and gender. The mean estimated volume of the preepiglottic and paraglottic space was 2.8 ml (SD 1.7 ml, range 0.7-5.9). No correlation with body mass index (p = 0.6), but a significant correlation with body area (p < 0.001) was found. A significant volume difference was present between men (mean 4.5 ml, SD 1.0 ml, range 2.8-5.9) and women (mean 1.4 ml, SD 0.5 ml, range 0.7-2.4)(p < 0.0001). Multiple regression analysis showed gender (p < 0.0001) to be a more important variable than body area (p = 0.17) in predicting the volume of the preepiglottic and paraglottic space. In conclusion, the volume of the preepiglottic and paraglottic space appears to be very variable, and should only be analysed with consideration of the gender of the examined subjects.