Figures
- Fig. 1.—
Schematic presentation of a model resembling the sinus (syringe), the ostium (syringe tip) and the nasal cavity (plastic cylinder). NO: nitric oxide.
- Fig. 2.—
Original tracing of nitric oxide (NO) during a single-breath nasal exhalation with humming (‐‐‐‐) or silently (––).
- Fig. 3.—
Effect of repeated humming manoeuvres on nasal nitric oxide (NO) output. Five consecutive exhalations with humming were performed at 5‐s intervals. A progressive reduction in NO output was observed after each manoeuvre until a plateau was reached.
- Fig. 4.—
Nasal nitric oxide (NO) output measured during a silent exhalation at baseline, immediately after repeated silent nasal exhalations and immediately after repeated humming manoeuvres (five consecutive 10‐s nasal exhalations with humming). #: p=0.002, as compared to baseline, n=6.
- Fig. 5.—
Change in nasal nitric oxide (NO) output after topical nasal application of an NO synthase inhibitor (l‐NAME). The subjects exhaled either silently (□) or with humming (┘). #: p=0.002, n=6.
- Fig. 6.—
Influence of ostium size on sinus gas exchange in a sinus/nasal model. A subject performed a single breath exhalation at a fixed flow rate (0.2 L·s−1) either silently (○) or with phonation (•). Sinus gas exchange was calculated by measuring nitric oxide in the syringe before and immediately after each exhalation.
- Fig. 7.—
The effect of three different humming frequencies (‐‐‐‐: 130 Hz; ––: 150 Hz; ······: 450 Hz) on nitric oxide (NO) output in a sinus/nasal model. A subject exhaled orally in the model at a fixed flow rate of 0.2 L·s−1, a NO concentration of 8 ppm, a resistance of 1cmH2O and an ostium size of 1.9 mm.
Tables
- Table 1
Effect of humming frequency on nitric oxide output (nL·min−1) using sinuses with different resonance frequency in the model
Humming frequency Sinus resonance frequency 120 Hz 200 Hz 120 Hz 1043±10 527±5.8 200 Hz 561±8.3 611±7.7 400 Hz 286±6.3 418±8.1 - Table 2
The influence of sinus volume, sinus nitric oxide (NO) concentration and flow rate on resulting NO output induced by an artificial pulsating airflow in a model of the nose and sinus with artficial humming
NO output nL·min−1 Sinus volume mL 5 79±1.0 10 159±4.5* 15 295±3.4* 20 427±3.7* NO concentration ppm 2 76±1.5 4 162±2.8* 8 295±3.4* 10 434±6.1* Flow L·s−1 0.20 295±3.4 0.25 369±5.8* 0.30 411±7.6* -
*: p<0.05
-
- Table 3
The influence of sinus volume, sinus nitric oxide (NO) concentration and flow rate on resulting NO output induced by human pulsating airflow in a model of the nose and sinus with human humming
NO output nL·min−1 Sinus volume mL 5 79±1.0 10 87±3.6* 15 175±8.0* 20 242±14.7* NO concentration ppm 2 57±8.1 4 118±14.6* 8 175±8.0* 10 416±32* Flow L·s−1 0.20 175±8.0 0.25 268±4.8* 0.30 356±10* -
*: p<0.05
-
