Resident Physician University of North Carolina - Chapel Hill Chapel Hill, North Carolina
Background: Individuals with cleft nasal deformity experience loss of smell. However, cleft associated olfactory dysfunction remains poorly understood. Learning Objectives: Investigate associations between conductive factors influencing olfaction and olfactory psychophysical assessment in unilateral cleft lip nasal deformity (uCLND). Study Objectives: Preliminary analysis to elucidate the pathophysiology underlying hyposmia in three patients with uCLND. Design Type: Pilot prospective cohort study to evaluate olfaction in patients with uCLND Method: Evaluations included (1) patient-reported nasal obstruction symptom evaluation (NOSE) survey; (2) Anterior rhinomanometry to measure transnasal resistance; (3) Smell Identification Test (SIT) and Snap & Sniff Threshold Test (SSTT) to measure olfaction. Also, radiographic images were obtained for creation of patient-specific nasal models for computational fluid dynamics (CFD) simulations of nasal airflow at 15L/min. Results: NOSE score ranged from 45 to 75. SIT scores were 20 – 33. Unilateral SSTT scores (in log vol/vol) were between -3.250 and -4.875 (cleft-side), between -3.875 and -4.875 (noncleft-side). Unilateral difference in resistance from rhinomanometry measurements indicated a more obstructed cleft-side for patients, between 122% and 3638%. CFD-computed bilateral resistance values were 0.0636 – 0.3768Pa.s/mL, and unilateral flow rates were 0.03 – 4.22L/min (cleft-side) and 10.78 – 14.97L/min (noncleft-side). Conclusion: SIT scores indicated varying degrees of hyposmia. SSTT scores were in the <40th percentile and in the “Smell-Impaired” group. Improved bilateral resistance from CFD results trended with smaller patients’ unilateral smell threshold difference. CFD results showed that increased unilateral nasal airflow volume leads to improved smell threshold. Our preliminary findings are consistent with conductive mechanisms contributing to hyposmia in uCLND.