[Evaluation of dysarthria with the assistance of acoustic speech analysis in patients with amyotrophic lateral sclerosis]. / Ocena dyzartrii za pomoca analizy akustycznego sygnalu mowy u chorych z stwardnieniem bocznym zanikowym.

The aim of the study was to assess dysarthria in ALS subjects using acoustic speech analysis. The study was performed in 47 definite or probable ALS patients aged 29-76 years (mean age 53.7 yr.) and in 30 age and sex matched healthy control subjects. Neurological examination showed 15 dysarthric ALS subjects. Acoustic speech analysis is a quantitative, computer-acoustic method estimating dysarthria and based on assessing of sound distance from speech sound tests. In both group the mean sound distance between chosen sounds was compared to a basic pattern and was measured on time-frequency computer acoustic analyses (delta f = 125 Hz, delta T = 9 ms, delta s = 0.5 dB). Our results demonstrated that all sounds were incorrect in all ALS subjects. These abnormalities were significantly increased in the dysarthric ALS subjects. The mean sound distances which separated ALS from control subjects is 0.2 (by Euclidian principle) in 4 out of 5 measured sounds. We suggest that it is possible to detect and measure dysarthria in ALS patients based on the acoustic speech analysis, also in the limb onset ALS subjects.

Acoustic analysis of dysarthria profile in ALS patients.

Dysarthria is a leading disability in ALS patients with motor neurone degeneration in the bulbar region. Although different approaches have been tried in the past, currently, no test is available to detect and follow the progression of dysarthria. We studied 53 patients with definite (n=27) or probable (n=26) ALS (the bulbar onset group n=15, the limb onset group n=38, mean age 53. 66/29-76 years/) according to El Escorial criteria. Each patient was seen by a neurologist every 10-12 weeks and clinical performance was assessed using the Norris scale. To evaluate dysarthria we developed a computer-based acoustic method. All patients had computer-analysed speech sound tests done three times. The most significantly affected vowels were selected for further studies. A method based on the Euclidian principle was used and the results were compared with 30 age, sex-matched, healthy control subjects. Our results demonstrated the existence of a specific dysarthria profile in ALS patients with most significantly affected vowels: 'B', 'O', 'I', 'W', 'T' in the bulbar group, and: 'B', 'I', 'T', 'W', 'O' in the limb group. This study suggests that it is possible to detect and monitor the progression of the disease based on the acoustic analysis of only several sounds. Abnormalities detected in the dysarthria profile may appear prior to any clinical symptoms of the disease.

Acoustic assessment of voice signal deformation after partial surgery of the larynx.

OBJECTIVE: The main objective of the present study was to assess the degree of voice signal impairment among patients who had undergone partial surgery of the larynx due to cancer of this organ. Such on evaluation may be helpful in the selection of the optimal surgical technique for the treatment of tumors displaying a varying degree of local advancement. METHODS: A prospective examination was carried out among 128 patients. Additionally a comparative study of the control group consisting of 36 healthy males was carried out. Acoustic tests were carried out in an echo-free chamber. The temporal changes in the value of acoustic pressure of the uttered text were registered. The 'distance' between the normal speech signal and the pathological voice has been established. RESULTS: The values of the fundamental frequency increase together with an increase of the range of resection of anatomical structures. The biggest differences in the value of results describing the distance from the standard were observed after hemilaryngectomy. The shortest distance from the acoustic standard was observed after chordectomy. No significant differences in the degree of voice signal impairment among patients who had undergone extended chordectomy and hemilaryngectomy were observed. CONCLUSION: The above findings can be of help in arriving at an optimum solution in cases of partial surgery of the larynx. The problem is particularly important in situations where there is the choice between different types of surgery.

Effectiveness of classical chordectomy in the treatment of cancer of the glottis.

From 1980 to 1992, 85 patients diagnosed with tumour of the glottis, localized exclusively in the vocal cord area, had undergone surgery. A 90% 5-year survival rate without recurrences had been obtained. Taking into account the cases of life-saving surgery, the percentage of the 5-year survivals amounted to 94%. Considerably better results were obtained by the excision of the entire vocal cord and not just one of its sections (1/2, 2/3 etc.). The degree of deformation of the voice following chordectomy was assessed by means of acoustic and laryngographic methods (Laryngograph Processor PCLX). A 13% rate of irregularity in the functioning of the neoglottis, following surgery, was observed. The Jitter-Shimmer co-efficients were established. The results of the deformation of the voice following chordectomy were presented on the J-S scale and compared with other partial surgeries performed on patients with tumours of the glottis. All of the acoustic and laryngographic findings were presented in the from of mean values most representative of chordectomy.