Long Island Veterinary Specialists Huntington Station, New York
Evaluation of Reduction Glossoplasty on Airway Resistance and Cross-Sectional Areas of the Upper Airway in Brachycephalic Dogs: A Cadaveric Study. Colberg VT, Kudej RK, Czajkowski PS, Karlin WM, Rozanski EA. Tufts University, Cummings School of Veterinary Medicine, Department of Clinical Sciences, North Grafton, MA.
Brachycephalic obstructive airway syndrome (BOAS) is a term used to describe the pathologic condition associated with altered respiratory function endured and compensated for by these breeds. Recent studies on brachycephalic dogs have examined the relative extent of pharyngeal airways occupied by tongue and palatal tissues. The objective of this study was to evaluate a potential contribution of tongue size to BOAS by measuring upper airway resistance and cross-sectional areas before and after midline reduction glossoplasty. Cadaveric brachycephalic dogs (n = 5) were retrograde intubated and airway resistance was calculated. Computed tomography was performed to evaluate cross-sectional areas of tongue, oropharynx, palatal soft tissue and nasopharynx at two levels, the caudal aspect of the hard palate, and hamulae of the pterygoid. Midline reduction glossoplasty was performed from the base of the epiglottis to the level of the 4th mandibular premolar. Positioning, airway resistance measurement and CT scan repeated. Reduction glossoplasty resulted in a 55% ± 7% reduction (P < 0.05) in upper airway resistance, a 25% decrease in cross-sectional area of the tongue at both the caudal hard palate (from 1402 ± 242 to 1061 ± 167 mm2; P < 0.05) and hamulae of the pterygoid (from 1052 ± 113 to 808 ± 150 mm2; P < 0.05), and a threefold increase in cross-sectional area of the oropharynx at both the caudal hard palate (from 253 ± 107 to 731 ± 212 mm2; P < 0.05) and hamulae of the pterygoid (from 139 ± 79 to 319 ± 97 mm2; P < 0.05). This study demonstrates a potential contribution of tongue size to upper airway obstruction in BOAS and significant improvement in airway resistance following reduction glossoplasty in cadaveric specimens.