THE NASAL CYCLE AFTER DEPRIVATION OF AIR-FLOW - A STUDY OF LARYNGECTOMY PATIENTS USING ACOUSTIC RHINOMETRY

Previous studies of the nasal cycle in laryngectomy patients using rhi nomanometric techniques concluded that the cycle was abolished as a re sult of the cessation of airflow after laryngectomy. This study was pe rformed with 20 postoperative laryngectomy patients (mean time after s urgery 4 years, range: 2 weeks to 10 years) and 10 control subjects ma tched for age and sex (including 2 preoperative patients). Acoustic rh inometry was used to determine minimum nasal cross-sectional area and nasal cavity volume as the indices of nasal patency. Testing was repea ted at intervals of 15-30 min over a period of 3-8 h. Fluctuations in nasal patency were observed in all laryngectomees and controls. The fl uctuations were classified as 'classical' (reciprocal alternating) in 5 (25%) laryngectomees and 5 (50%) controls. An 'irregular' pattern of fluctuation was seen in 8 (40%) laryngectomees and 2 (20%) controls. An 'in concert' cyclical pattern was seen in 7 (35%) laryngectomees an d 3 (30%) controls. This is the first demonstration of retention of th e nasal cycle after airflow deprivation. Whilst the cycle may in some instances be modified after operation, it is not abolished. The centra l generation of the cycle is confirmed, although afferent input from a irflow receptors may play a role in modulating the cycle's pattern and amplitude.