Adaptation of nasometry to Hungarian language and experiences with its clinical application.
OBJECTIVES: (1) To adopt the nasometry for the Hungarian language and to obtain normative nasalance scores. (2) To compare our results with the data of other languages and to evaluate the correlation between nasalance scores and perceptual ratings of nasality. (3) To use the nasometry in various fields of the otolaryngological, phoniatric, and logopedic diagnostics, therapy and documentation. METHODS: (1) To determine the normative nasalance scores regarding the Hungarian language, we included 30 children aged 5-7 years and 45 adults in the 20-25 years age group. In the latter group 15 subjects were speech therapists and 30 phonetically untrained people-15 males and 15 females. STUDY DESIGN: phonation of isolated vowels, articulation of spirants, cyclical repetition of affricates, pronunciation of various (oral, nasal, mixed type) sentences and evaluation of the nasalance score in continuous speech. (2) Thirty-six persons (12 speech pathologists, 12 logopedic students, 12 phonetically uneducated individuals) evaluated the children's physiological and nasal speech recordings with a 3-point scale. (3) Two hundred and forty-eight children of kindergarten age were examined, 20 infants and 6 adult singers in the following fields: evaluation of hypernasality due to cleft palate or velopharyngeal insufficiency (VPI), and of the success of the therapy; examination of hyponasality in cases of enlarged adenoid and allergic rhinitis; evaluation of the speech of hard-of-hearing people; differentiation between nasal sigmatism and hyperrhinophony; testing of the resonance in professional singers; examination of infant cry; application of nasometry in the therapy. RESULTS: The mean value of the nasalance score using the oral sentence: "Zsuzsi kutyája ugat" is 11-13%, in the nasal sentence ("A majom banánt enne") 56%, while that of the mixed sentence representing the Hungarian language ("Jó napot kívánok!") falls in the 30-40% range. The resonance grows with aging and there is no significant difference between genders. The nasalance score is greater with phonetically trained people. Our data correlate with the values of other languages. The correlation is significant between the nasalance scores and perceived nasality (r=0.901). Practical results: Values above 40% in cases of VPI using mixed sentences may support the indication of velopharyngoplasty, together with the subjective evaluation of nasality and other tests. In cases with rhinitis and adenoid vegetation the nasalance score remains below 20%. The nasality value is increased in sensorineural hearing loss, and is decreased in cases with conducting hearing impairment. In nasal sigmatism not the vowels' but the nasality of consonants grow. The difference between the nasalance score of the cry in clefted and non-cleft infants is significant (26% versus 36%): this observation could give possibility in the future to screen babies with congenital hearing problems or hidden VPI. Alterations in nasalance can be documented with nasometry in professional singers when they increase the nasal resonance to grow the power capacity of their voice. The nasometry procedure is a significant help also in speech therapy through the real time visual and auditive control. CONCLUSIONS: The otolaryngological, phoniatric and logopedic diagnostics and therapy is significantly widened with nasometry which is a quick, non-invasive and objective procedure, measuring the nasal resonance of the speech.