Eileen T. Dalston

Effect of age on nasal cross-sectional area and respiratory mode in children

Although nasal cross‐sectional size has been reported for adults, no information is available concerning the effects of age on nasal area and breathing mode in children. Determination of the effect of age on nasal size is necessary in order to define nasal airway impairment in children. The purpose of this study was to determine mean nasal cross‐sectional size in children between the ages of 6 and 15 years. One hundred two children were assessed during resting breathing. The pressure‐flow technique was used to estimate nasal cross‐sectional size, and inductive plethys‐mography was used to assess nasal‐oral breathing. The results indicate that nasal airway size increased approximately 0.032 cm2 each year. Mean nasal cross‐sectional area increased from 0.21 ± 0.05 cm2 at age 6 to 0.46 ± 0.15 cm2 at age 14. The percentage of nasal breathing also increased with age.

The identification of nasal obstruction through clinical judgments of hyponasality and nasometric assessment of speech acoustics

This study examined the records of a consecutive series of 79 patients referred for evaluation at the Oral-Facial and Communicative Disorders Program during a 3-month period in 1989. The purpose was to determine whether clinical judgments of hyponasality, based on a six-point equal-appearing interval scale or an acoustic assessment with a Kay Elemetrics nasometer could provide information concerning nasal airway patency comparable to that obtained by means of aerodynamic measurement techniques. Among the 40 adults in the series, the sensitivity of hyponasality ratings was 0.55 when nasal airway impairment was defined as a condition in which the airway was less than 0.40 and 0.71 when the definition was limited to airways of less than 0.30 cm2. Specificities for the two groups were 0.89 and 0.85, respectively. Similarly, the sensitivity of nasometer ratings was 0.30 for the first group and 0.38 for the second group, while the specificity for the two groups was 0.83 and 0.92, respectively. Comparable analyses for children were not possible because of the extent to which nasal airway size varies in children younger than 15 years of age. Possible reasons for the findings and their clinical significance are discussed.

A preliminary study of nasal airway patency and its potential effect on speech performance.

The relationship between nasal airway size and articulatory performance was studied in a group of cleft palate patients. Articulation analysis revealed that children with bilateral cleft lip and palate were nearly twice as likely to manifest compensatory articulations as children with unilateral cleft lip and palate or with cleft palate only. When subjects were grouped according to speech performance, aerodynamic assessment indicated that children with compensatory articulations had significantly larger nasal cross-sectional areas than children without compensatory articulations. The findings suggest that children with comparatively large nasal airways may be at increased risk for developing abnormal speech patterns. If these findings are confirmed by further research, such children may be candidates for relatively early palate repair.

The Relationship between Nasal Airway Size and Nasal-Oral Breathing in Cleft Lip and Palate:

Clefts of the lip and palate generally result in reduced size of the nasal airway. Procedures such as the placement of a pharyngeal flap tend to further compromise nasal breathing. The purpose of this study was to determine how size of the nasal airway affects the mode of breathing in adults with cleft lip and/or palate. A heterogeneous population of 50 adult subjects with cleft lip and/or palate was studied. Nineteen of the subjects had pharyngeal flaps. Respiratory inductive plethysmography was used in combination with an integrating pneumotachograph to measure percent nasal breathing. Pressure-flow studies were used to estimate nasal airway size. The data revealed that a majority of subjects had an airway size of less than 0.4 cm2, which constitutes impairment. Mean cross-sectional area for all subjects was 0.38 cm2 +/- 0.20 SD. Seventy percent of the subjects studied were oral breathers to some extent. A Spearman rank correlation coefficient of 0.725 (p less than 0.0001) indicated that oral-nasal breathing mode was related to airway size. Airway size in the subgroup with pharyngeal flaps was even smaller (0.31 cm2), while percent nasal breathing was lower. Mouthbreathing was observed in all subjects whose airway size was less than 0.38 cm2.