[Normal nasalance for the German language. Nasometric values for clinical use in patients with cleft lip and palate]

Differences in velopharyngeal pressures during speech sound production in patients with unilateral cleft lip and palate (UCLP) and healthy individuals

Background

During articulation the velopharynx needs to be opened and closed rapidly and a tight closure is needed. Based on the hypothesis that patients with cleft lip and palate (CLP) produce lower pressures in the velopharynx than healthy individuals, this study compared pressure profiles of the velopharyngeal closure during articulation of different sounds between healthy participants and patients with surgically closed unilateral CLP (UCLP) using high resolution manometry (HRM).

Materials and methods

Ten healthy adult volunteers (group 1: 20-25.5 years) and ten patients with a non-syndromic surgically reconstructed UCLP (group 2: 19.1-26.9 years) were included in this study. Pressure profiles during the articulation of four sounds (/i:/, /s/, /ʃ/ and /n/) were measured by HRM. Maximum, minimum and average pressures, time intervals as well as detection of a previously described 3-phase-model were compared.

Results

Both groups presented with similar pressure curves for each phoneme with regards to the phases described and pressure peaks, but differed in total pressures. An exception was noted for the sound /i:/, where a 3-phase-model could not be seen for most patients with UCLP. Differences in velopharynx pressures of 50% and more were found between the two groups. Maximum and average pressures in the production of the alveolar fricative reached statistical significance.

Conclusions

It can be concluded that velopharyngeal pressures of patients with UCLP are not sufficient to eliminate nasal resonance or turbulence during articulation, especially for more complex sounds. These results support a general understanding of hypernasality during speech implying a (relative) velopharyngeal insufficiency.

Finite element modeling of the effects of velopharyngeal opening on vocal tract reactance in female voice

Classical singers use nasal consonants as "resonance exercises," and experimental results have shown that singers may use some velopharyngeal opening (VPO), most often in [a:] and more seldom in [i:] or [u:]. In particular, male singers have been found to increase VPO as pitch rises toward register change frequencies (passaggi). Laryngoscopic findings have shown that some VPO stabilizes vocal fold vibration; the effect is related to positive reactance. This study investigates the effects of VPO on vocal tract (VT) reactance over the range of fundamental frequencies (f₀) used in singing using a computerized tomography-based finite element model of the VT and nose of a female. According to the results, by raising the lowest VT resonances, the VPO increased the VT reactance in the frequency ranges 207-359 Hz for [i:], 265-411 Hz for [u:], and 500-611 Hz for [a:], depending on the VPO size (full or half VPO). These frequency ranges are close to the first and second passaggio of a female singer. The change may have an especially practical stabilizing effect for [a:], which is otherwise characterized by very large changes in VT reactance and negative reactance at the second passaggio.

Normative data on nasalance scores for Farsi speaking children: Influence of age, gender and phonetic context

BACKGROUND

Normative nasalance scores are essential for treatment and assessment purposes for clinicians. The purpose of the current study is to determine the normative data on nasalance scores for Farsi speaking children. Comparing to the obtained normative data, hypernasal or hyponasal speech (i.e. the higher or lower nasalance score) can be evaluated.

METHODS

Ninety-six Farsi speakers ranging from 4 years to 11 years old with typically developing speech were included in this study. Mean nasalance scores were obtained using the Universal Parameters System sentences with nasometer II (model 6450). The nasalance data was also analyzed for any gender, age and phonetic context dependence.

RESULTS

Normative nasalance values were determined, Nno differences were found for gender and age for the school-aged children. With an increasing in age, the nasalance score also increased in oral passages but not in nasal passages. Furthermore, amongst the nasalance scores there was a significant difference between these four categories of sentences: 7 sentences loaded with oral stop consonants, 5 sentences loaded with oral fricative consonants, 2 sentences loaded with oral affricatives and 3 sentences loaded with nasal consonants.

CONCLUSIONS

The absence of age and gender differences led to a computation of an overall mean nasalance score for different types of phonetic context (Nasal, oral and oronasal). These normative nasalance data for Farsi speaking children will provide important reference information during speech assessments of children with velopharyngeal insufficiency.

Nasalance norms in Greek adults

The purposes of this study were to derive nasalance norms for monolingual Greek speakers, to examine nasalance scores as a function of gender and to draw cross-linguistic comparisons based on normative data. Participants read aloud a corpus of linguistic material, consisting of (1) a nasal text, an oral text and a balanced text; (2) a set of nasal sentences and four sets of oral sentences and (3) repetitions of each of 12 syllable types (8 oral and 4 nasal). The last two sets of material corpus were based on an adaptation of the Simplified Nasometric Assessment Procedures Test (SNAP test) test ( MacKay and Kummer, 1994 ) in Greek, called the G-SNAP test. Eighty monolingual healthy young adult speakers of Greek, 40 males (mean age = 21 years) and 40 females (mean age = 20.5 years), with normal hearing and speech characteristics and unremarkable history were included in the study. The Nasometer (model 6200-3) was used to derive nasalance scores. Mean normative nasalance for spoken Greek was 25.50%, based on the G-oronasal text (with 8.6% nasals). Nasalance scores did not differ significantly with respect to gender. Finally, spoken Greek consistently yielded lower nasalance scores than other languages examined in past work. The aforementioned normative data on nasalance of young adult speakers of Greek are valid across gender and have direct clinical utility as they provide valuable reference information for the diagnosis and management of Greek adults with resonance disorders caused by velar dysfunction.

Die diagnostische Wertigkeit der Nasometrie – eine repräsentative Studie für Patienten mit Lippen-Kiefer-Gaumensegel-Spalten und Gesunde

In the rehabilitation of cleft palate patients the quality of spoken language represents one of the most important aspects of successful social integration. It is therefore necessary to direct special attention to phoniatric care and speech therapy following operative reconstruction. One of the main problems is the comparison of subjective and objective measures of the degree and type of nasal disorder. In an interdisciplinary project at the University of Jena nasometry was assessed. Due to a lack of norm values for German a representative sample for the calibration of cleft palate patients and normal subjects was collected. Speech was elicited using standardized and phonetically validated reading materials. Nasalance measurements were compared with judgements made by a group of trained listeners who were asked to assess voice quality (RBH) and nasality. A database containing nasalance values and acoustic signals from 120 subjects was built up. The results generally exhibited highly significant correlations between instrumental measurements and auditory judgements. Profiles of norm values for a phonetically and statistically reliable standard for German were obtained, which in turn can be used as a comparative basis for further studies.

Evaluation of speech intelligibility for children with cleft lip and palate by means of automatic speech recognition

OBJECTIVE

Cleft lip and palate (CLP) may cause functional limitations even after adequate surgical and non-surgical treatment, speech disorders being one of them. Interindividually, they vary a lot, showing typical articulation specifics such as nasal emission and shift of articulation and therefore a diminished intelligibility. Until now, an objective means to determine and quantify the intelligibility does not exist.

METHOD

An automatic speech recognition system, a new method, was applied on recordings of a standard test to evaluate articulation disorders (psycholinguistic analysis of speech disorders of children PLAKSS) of 31 children at the age of 10.1+/-3.8 years. Two had an isolated cleft lip, 20 a unilateral cleft lip and palate, 4 a bilateral cleft lip and palate, and 5 an isolated cleft palate. The speech recognition system was trained with adults and children without speech disorders and adapted to the speech of children with CLP. In this study, the automatic speech evaluation focussed on the word accuracy which represents the percentage of correctly recognized words. Results were confronted to a perceptive evaluation of intelligibility that was performed by a panel of three experts.

RESULTS

The automatic speech recognition yielded word accuracies between 1.2 and 75.8% (mean 48.0+/-19.6%). The word accuracy was lowest for children with isolated cleft palate (36.9+/-23.3) and highest for children with isolated cleft lip (72.8+/-2.9). For children with unilateral cleft lip and palate it was 48.0+/-18.6 and for children with bilateral cleft lip and palate 49.3+/-9.4. The automatic evaluation complied with the experts' subjective evaluation of intelligibility (p<0.01). The multi-rater kappa of the experts alone differed only slightly from the multi-rater kappa of experts and recognizer.

CONCLUSION

Automatic speech recognition may serve as a good means to objectify and quantify global speech outcome of children with cleft lip and palate.

Veränderung der Nasalanz nach Le Fort-I Osteotomie

BACKGROUND

Nasalance represents a measure of the relative amount of oral and nasal acoustic energy produced by a speaker. Literature shows changes in nasalance after surgery of the oropharynx. The aim of this prospective study was to evaluate the outcome of speech and nasalance scores after Le-Fort-I-Osteotomy.

PATIENTS AND METHODS

A total of 20 individuals with normal speech development were examined preoperatively and 6 weeks postoperatively with the Nasometer 6200 (Kay-Elemetrics, USA) after bimaxillary surgery. The tone materials used comprised the standardized text passage: "Ein Kindergeburtstag", the vowels: /a/, /e/, /i/, /o/, /u/ and a syllable repetition subtest.

RESULTS

All patients showed changes in nasalance scores 6 weeks postoperatively. There were no significant changes reading the standard text. The syllable repetition test showed significant changes for repetition of "ma ma ma" and "na na na" (p=0,003, respectively p=0,033). Intonation of the vowel /a/1 also revealed significant changes regarding the pre- and postoperative values (p=0,006). However, the obtained values had no significant impact on the nasality characteristics of speech.

CONCLUSION

This study confirms that maxillary osteotomies can result in significant changes of nasalance scores. However these changes do not have any impact on normal speech and voice.

Nasalance Measures in German-Speaking Cleft Patients

The purpose of this study was to evaluate nasalance measures in German-speaking patients with different types of repaired cleft lip and palate and to find out if significant nasalance gender differences exist in the different cleft groups. A total of 125 German-speaking cleft patients (74 male and 51 female) were included in this study: 18 patients with isolated unilateral cleft lip (UCL; mean age: 13.00 +/- 2.03 years), 66 patients with complete unilateral cleft lip and palate (UCLP; mean age: 14.80 +/- 3.45 years), 25 patients with isolated cleft palate (CP; mean age: 14.60 +/- 3.48 years), and 16 patients with complete bilateral cleft lip and palate (BCLP; mean age: 14.30 +/- 3.61 years). Nasalance data were collected and computed using the NasalView hardware/software system (Fa. Tiger Electronics, Seattle, WA). Speech stimuli according to a modified Heidelberg Rhinophonia Assessment Form (sustained vowels "a," "e," "i," "o," and "u"; oral and nasal sentences; and three oral-nasal reading passages) were used to obtain nasalance scores. Nasalance distance and ratio were also calculated for the oral and nasal sentences and for one of the oral-nasal reading passages. Unpaired t tests showed no significant gender nasalance differences in each cleft group. Analysis of variance showed no significant differences in mean nasalance distance and ratio. For the nasal sentence, a significant difference (P = 0.032) in mean nasalance scores was found between the UCL and UCLP groups.

[Long-term results after velopharyngoplasty]

BACKGROUND

Children with cleft palate frequently demonstrate speech and resonance disorders following primary cleft repair. In some patients no improvement can be achieved with conservative therapy and a velopharyngoplasty (VPP) may be indicated. This study was performed to evaluate the long-term results after VPP.

MATERIAL AND METHODS

Twenty-six patients were followed up on an average 9 years after VPP (mean age: 16+/-5 years). Apart from the phoniatric-pedaudiologic findings, the speech intelligibility and nasality were judged by speech pathologists and by laymen. The extent of the speech handicaps was evaluated with a questionnaire. The nasalance was measured with NasalView. The vowels, two test sentences, and three reading texts (LT(1-3)) were used as test materials.

RESULTS

The phoniatric-pedaudiologic examination revealed a clear improvement of hearing, language, and speech function. Compared to the previous results, decreased nasality and improved ability in articulation were detected. The judgment of laymen was also positive. The speech intelligibility was mostly evaluated as favorable. A speech handicap was present in only a few patients. The evaluation using NasalView showed significantly increased nasalance values for the LT(2) ( p=0.030). Moreover there were lower nasalance values for all the reading texts compared to the control group (LT(1) p=0.257, LT(2) p=0.408, LT(3) p=0.187).

CONCLUSION

A clear improvement can be achieved with VPP in patients with a high degree of therapy-resistant nasality. In many cases even normal colloquial language is possible. The evaluation of nasalance has proved to be successful for rating surgical outcome.