Analysis of formant frequencies in patients with oral or oropharyngeal cancers treated by glossectomy

Machine learning in the evaluation of voice and swallowing in the head and neck cancer patient

PURPOSE OF REVIEW

The purpose of this review is to present recent advances and limitations in machine learning applied to the evaluation of speech, voice, and swallowing in head and neck cancer.

RECENT FINDINGS

Novel machine learning models incorporating diverse data modalities with improved discriminatory capabilities have been developed for predicting toxicities following head and neck cancer therapy, including dysphagia, dysphonia, xerostomia, and weight loss as well as guiding treatment planning. Machine learning has been applied to the care of posttreatment voice and swallowing dysfunction by offering objective and standardized assessments and aiding innovative technologies for functional restoration. Voice and speech are also being utilized in machine learning algorithms to screen laryngeal cancer.

SUMMARY

Machine learning has the potential to help optimize, assess, predict, and rehabilitate voice and swallowing function in head and neck cancer patients as well as aid in cancer screening. However, existing studies are limited by the lack of sufficient external validation and generalizability, insufficient transparency and reproducibility, and no clear superior predictive modeling strategies. Algorithms and applications will need to be trained on large multiinstitutional data sets, incorporate sociodemographic data to reduce bias, and achieve validation through clinical trials for optimal performance and utility.

Effects of oral and oropharyngeal cancer on speech intelligibility using acoustic analysis: Systematic review

BACKGROUND

The development of automatic tools based on acoustic analysis allows to overcome the limitations of perceptual assessment for patients with head and neck cancer. The aim of this study is to provide a systematic review of literature describing the effects of oral and oropharyngeal cancer on speech intelligibility using acoustic analysis.

METHODS

Two databases (PubMed and Embase) were surveyed. The selection process, according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement, led to a final set of 22 articles.

RESULTS

Nasalance is studied mainly in oropharyngeal patients. The vowels are mostly studied using formant analysis and vowel space area, the consonants by means of spectral moments with specific parameters according to their phonetic characteristic. Machine learning methods allow classifying "intelligible" or "unintelligible" speech for T3 or T4 tumors.

CONCLUSIONS

The development of comprehensive models combining different acoustic measures would allow a better consideration of the functional impact of the speech disorder.

Acoustic Characteristics in Epiglottic Cyst

OBJECTIVE

The purpose of this study was to analyze the acoustic characteristics associated with alternation deformation of the vocal tract due to large epiglottic cyst, and to confirm the relation between the anatomical change and resonant function of the vocal tract.

METHODS

Eight men with epiglottic cyst were enrolled in this study. The jitter, shimmer, noise-to-harmonic ratio, and first two formants were analyzed in vowels /a:/, /e:/, /i:/, /o:/, and /u:/. These values were analyzed before and after laryngeal microsurgery.

RESULTS

The F1 value of /a:/ was significantly raised after surgery. Significant differences of formant frequencies in other vowels, jitter, shimmer, and noise-to-harmonic ratio were not presented.

CONCLUSION

The results of this study could be used to analyze changes in the resonance of vocal tracts due to the epiglottic cysts.

Analysis of speech and tongue motion in normal and post-glossectomy speaker using cine MRI

Objective

Since the tongue is the oral structure responsible for mastication, pronunciation, and swallowing functions, patients who undergo glossectomy can be affected in various aspects of these functions. The vowel /i/ uses the tongue shape, whereas /u/ uses tongue and lip shapes. The purpose of this study is to investigate the morphological changes of the tongue and the adaptation of pronunciation using cine MRI for speech of patients who undergo glossectomy.

Material and Methods

Twenty-three controls (11 males and 12 females) and 13 patients (eight males and five females) volunteered to participate in the experiment. The patients underwent glossectomy surgery for T1 or T2 lateral lingual tumors. The speech tasks “a souk” and “a geese” were spoken by all subjects providing data for the vowels /u/ and /i/. Cine MRI and speech acoustics were recorded and measured to compare the changes in the tongue with vowel acoustics after surgery. 2D measurements were made of the interlip distance, tongue-palate distance, tongue position (anterior-posterior and superior-inferior), tongue height on the left and right sides, and pharynx size. Vowel formants Fl, F2, and F3 were measured.

Results

The patients had significantly lower F2/Fl ratios (F=5.911, p=0.018), and lower F3/F1 ratios that approached significance. This was seen primarily in the /u/ data. Patients had flatter tongue shapes than controls with a greater effect seen in /u/ than /i/.

Conclusion

The patients showed complex adaptation motion in order to preserve the acoustic integrity of the vowels, and the tongue modified cavity size relationships to maintain the value of the formant frequencies.

Effect of Rapid Maxillary Expansion on Voice

OBJECTIVE

The purpose of this investigation is to evaluate the effect of rapid maxillary expansion (RME) on the fundamental frequency (F0) and formant frequencies F1-F4.

STUDY DESIGN

Cross-sectional study.

MATERIALS AND METHODS

A total of 14 consecutive patients between the ages of 9.6 years and 15 years with a constricted maxilla undergoing RME were included in this study. Measurements were made before (T1) and after treatment (T2). These included maxillary arch length, depth, width, and perimeter in addition to F0, habitual pitch, and formants F1, F2, F3, and F4 for the vowels /ɑ/, /i/, /o/, and /u/.

RESULTS

There was a significant difference in the mean of F1/ɑ/ and F2/ɑ/ before and after treatment (P value of 0.04 and 0.013, respectively). It is worth noting that F1/ɑ/ decreased in 11 and F2/ɑ/ decreased in 10 of the 14 subjects.

CONCLUSION

The application of RME in the treatment of maxillary constriction leads to a significant lowering of the first and second formants for the vowel /ɑ/ in most subjects. Subjects undergoing rapid maxillary application should be aware of the potential change in voice quality especially in case of professional voice users.

Acoustic parameters of speech: Lack of correlation with perceptual and questionnaire-based speech evaluation in patients with oral and oropharyngeal cancer treated with primary surgery

BACKGROUND

Acoustic evaluation of speech is the least explored method of speech evaluation in patients with oral cavity and oropharyngeal cancer. The purpose of this study was to explore acoustic parameters of speech and their correlation with questionnaire evaluation and perceptual evaluation in patients with oral cavity and oropharyngeal cancer.

METHODS

One hundred seventeen subjects (65 consecutive patients with oral cavity and oropharyngeal cancer and 52 controls) participated in this study. Formant frequencies (by Linear Predictive Coding), Speech Handicap Index, and London Speech Evaluation scale were used for acoustic evaluation, questionnaire evaluation, and perceptual evaluation, respectively.

RESULTS

Men showed significant elevation in second formant (F2) values for patients with oral cavity cancer and those who underwent surgery alone. Female patients with early T classification cancers and those who underwent surgery and chemoradiation showed significant reduction in the mean F2 values. Importantly, however, acoustic evaluation parameters did not correlate with either perceptual evaluation or questionnaire evaluation parameters, although there was moderate correlation between questionnaire evaluation and perceptual evaluation speech parameters.

CONCLUSION

Acoustic evaluation modalities have no clear role in the management of patients with oral cavity and oropharyngeal cancer.

Speech production after glossectomy: methodological aspects

This article focuses on methodological issues related to quantitative assessments of speech quality after glossectomy. Acoustic and articulatory data were collected for 8 consonants from two patients. The acoustic analysis is based on spectral moments and the Klatt VOT. Lingual movements are recorded with ultrasound without calibration. The variations of acoustic and articulatory parameters across pre- and post-surgery conditions are analyzed in the light of perceptual evaluations of the stimuli. A parameter is considered to be relevant if its variation is congruent with perceptual ratings. The most relevant acoustic parameters are the skewness and the Center of Gravity. The Klatt VOT explains differences that could not be explained by spectral parameters. The SNTS ultrasound parameter provides information to describe impairments not accounted for by acoustical parameters. These results suggest that the combination of articulatory, perceptual and acoustic data provides comprehensive complementary information for a quantitative assessment of speech after glossectomy.

Outcome measurements after oral cancer treatment: speech and speech-related aspects--an overview

INTRODUCTION

Oral cancer and its surgical treatment impair speech quality by an alteration of the vocal tract. Local size and stage of the tumour as well as surgical and adjuvant treatment modalities have an impact on the functional outcome of patients' speech rehabilitation. It was the aim of this overview to specifiy speech and speech-related aspects as well as to delineate measurement methods of speech outcome in patients with oral cancer by a review of the literature.

METHODS

The review is based on a Medline Search on "speech", "cancer", "oral cancer", "malignoma mouth", "intelligibility", "formant", "ultrasound".

DISCUSSION

In particular, speech intelligibility is inevitable for the social interaction of patients which is highly correlated with the patient's quality of life. However, speech outcome measurement shows a variety of methods without an international standardisation. Additionally, several co-aspects of speech production have to be considered: tongue mobility, voice production, velopharyngeal closure and neural coordination are important influencing factors. Speech assessment is traditionally performed by perceptual methods on a subjective or semi-subjective base. More objective, technical-based methods of speech evaluation are in development and under research.

PURPOSE

It was the aim of this overview to specify speech and speech-related aspects as well as to delineate measurement methods of speech outcome in patients with oral cancer by a review of the current literature.

Recovery of speech following total glossectomy: an acoustic and perceptual appraisal

This study involved an acoustic and perceptual analysis of the speech produced by a 31-year-old female following total glossectomy. Speech samples were collected on three occasions within the first 3 months following glossectomy. Vowel articulation was examined acoustically as a function of vowel space and the Euclidean distance separating corner vowels. Perceptual analyses involved presentation of the participant's CV productions to 30 healthy adult listeners who made forced-choice identifications of consonant type. Acoustic analysis revealed improvements in vowel space area and an increase in the Euclidean distances. The perceptual results revealed a statistically significant deterioration in consonants over the 3-month period with anterior sounds being perceived more correctly than medial and posterior sounds. The current study highlights the variable nature of speech following glossectomy, with greater improvements in vowel articulation compared to consonant articulation during the earliest stages of surgical recovery.

Artificial neural network analysis to assess hypernasality in patients treated for oral or oropharyngeal cancer

OBJECTIVE

Investigation of applicability of neural network feature analysis of nasalance in speech to assess hypernasality in speech of patients treated for oral or oropharyngeal cancer.

PATIENTS AND METHODS

Speech recordings of 51 patients and of 18 control speakers were evaluated regarding hypernasality, articulation, intelligibility, and patient-reported speech outcome. Feature analysis of nasalance was performed on /a/, /i/, and /u/ and on the entire stretch of speech.

RESULTS

Nasalance distinguished significantly between patients and controls. Nasalance in /a/ and /i/ predicted best intelligibility, nasalance in /a/ predicted best articulation, and nasalance in /i/ and /u/ predicted best hypernasality.

CONCLUSION

Feature analysis of nasalance in oral or oropharyngeal cancer patients is feasible; prediction of subjective parameters varies between moderate and poor.

Speech after radial forearm free flap reconstruction of the tongue: a longitudinal acoustic study of vowel and diphthong sounds

The purpose of this study was to use acoustic analyses to describe speech outcomes over the course of 1 year after radial forearm free flap (RFFF) reconstruction of the tongue. Eighteen Canadian English-speaking females and males with reconstruction for oral cancer had speech samples recorded (pre-operative, and 1 month, 6 months, and 1 year post-operative). Acoustic characteristics of formants (F1, F2), fundamental frequency (F0), and duration of 699 vowel and diphthong tokens were analysed. Furthermore, the changes in size of the vowel space area were studied, as well as the effects of radiation therapy (RT) and inclusion of the floor of the mouth (FOM) in the reconstruction. RFFF reconstruction was found to affect several characteristics in males, and a minimal number of variables in females. General signs of reduced ability to articulate were not observed. RT and FOM had no differing effects compared to non-RT or non-FOM. There were individual differences between patients.