PURPOSE: Laryngeal high-speed videoendoscopy (LHSV) has been recognized as a highly valuable modality for the scientific investigations of vocal fold (VF) vibrations. In contrast to stroboscopic imaging, LHSV enables visualizing aperiodic VF vibrations. However, the technique is less well established in the clinical care of disordered voices, partly because the properties of aperiodic vibration patterns are not yet described comprehensively. To address this, a computer model for simulation of VF vibration patterns observed in a variety of different phonation types is proposed. METHOD: A previously published kinematic model of mucosal wave phenomena is generalized to be capable of left-right asymmetry and to simulate endoscopic videos instead of only kymograms of VF vibrations at single sagittal positions. The most influential control parameters are the glottal halfwidths, the oscillation frequencies, the amplitudes, and the phase delays. RESULTS: The presented videos demonstrate zipper-like vibration, pressed voice, voice onset, constant and time-varying left-right and anterior-posterior phase differences, as well as left-right frequency differences of the VF vibration. Video frames, videokymograms, phonovibrograms, glottal area waveforms, and waveforms of VF contact area relating to electroglottograms are shown, as well as selected kinematic parameters. CONCLUSION: The presented videos demonstrate the ability to produce vibration patterns that are similar to those typically seen in endoscopic videos obtained from vocally healthy and dysphonic speakers. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.20151833.
INTRODUCTION: The sharpness of lateral peaks is a visually helpful clinical feature in high-speed videokymographic (VKG) images indicating vertical phase differences and mucosal waves on the vibrating vocal folds and giving insights into the health and pliability of vocal fold mucosa. This study aims at investigating parameters that can be helpful in objectively quantifying the lateral peak sharpness from the VKG images. METHOD: Forty-five clinical VKG images with different degrees of sharpness of lateral peaks were independently evaluated visually by three raters. The ratings were compared to parameters obtained by automatic image analysis of the vocal fold contours: Open Time Percentage Quotients (OTQ) and Plateau Quotients (PQ). The OTQ parameters were derived as fractions of the period during which the vocal fold displacement exceeds a predetermined percentage of the vibratory amplitude. The PQ parameters were derived similarly but as a fraction of the open phase instead of a period. RESULTS: The best correspondence between the visual ratings and the automatically derived quotients were found for the OTQ and PQ parameters derived at 95% and 80% of the amplitude, named OTQ95, PQ95, OTQ80 and PQ80. Their Spearman's rank correlation coefficients were in the range of 0.73 to 0.77 (P < 0.001) indicating strong relationships with the visual ratings. The strengths of these correlations were similar to those found from inter-rater comparisons of visual evaluations of peak sharpness. CONCLUSION: The Open time percentage and Plateau quotients at 95% and 80% of the amplitude stood out as the possible candidates for capturing the sharpness of the lateral peaks with their reliability comparable to that of visual ratings.
- MeSH
- audiovizuální záznam * MeSH
- automatizace MeSH
- biomechanika MeSH
- časové faktory MeSH
- fonace * MeSH
- hlasové řasy diagnostické zobrazování patofyziologie MeSH
- interpretace obrazu počítačem * MeSH
- kvalita hlasu * MeSH
- kymografie * MeSH
- laryngoskopie MeSH
- lidé MeSH
- mínění MeSH
- poruchy hlasu diagnostické zobrazování patofyziologie MeSH
- prediktivní hodnota testů MeSH
- retrospektivní studie MeSH
- sliznice hrtanu diagnostické zobrazování patofyziologie MeSH
- vibrace MeSH
- zraková percepce * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Purpose: Sound pressure level (SPL) and fundamental frequency (fo) are very basic and important measures in the acoustical assessment of voice quality, and their variation influences also the vocal fold vibration characteristics. Most sophisticated laryngeal videostroboscopic systems therefore also measure and display the SPL and fo values directly over the video frames by means of a rather expensive special hardware setup. An alternative simple software-based method is presented here to obtain these measures as video subtitles. Method: The software extracts acoustic data from the video recording, calculates the SPL and fo parameters, and saves their values in a separate subtitle file. To ensure the correct SPL values, the microphone signal is calibrated beforehand with a sound level meter. Results: The new approach was tested on videokymographic recordings obtained laryngoscopically. The results of SPL and fo values calculated from the videokymographic recording, subtitles creation, and their display are presented. Conclusions: This method is useful in integrating the acoustic measures with any kind of video recordings containing audio data when inbuilt hardware means are not available. However, calibration and other technical aspects related to data acquisition and synchronization described in this article should be properly taken care of during the recording.
- MeSH
- akustika řeči * MeSH
- audiovizuální záznam * MeSH
- fonace MeSH
- hlasové řasy patofyziologie MeSH
- kalibrace MeSH
- kvalita hlasu MeSH
- laryngoskopie metody MeSH
- larynx patofyziologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- měření tvorby řeči metody MeSH
- software MeSH
- tlak MeSH
- vibrace MeSH
- zvuková spektrografie metody MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
