Post-Processing of High-Speed Video-Laryngoscopic Images to Two-Dimensional Scanning Digital Kymographic Images

BACKGROUND AND OBJECTIVES: High-speed videolaryngoscopy (HSV) is the only technique that captures the true intra-cycle vibratory behavior of the vocal folds by capturing full images of the vocal folds. However, it has problems of no immediate feedback during examination, considerable waiting time for digital kymography (DKG), recording duration limited to a few seconds, and extreme demands for storage space. Herein, we demonstrate a new post-processing method that converts HSV images to two-dimensional digital kymography (2D-DKG) images, which adopts the algorithm of 2D videokymography (2D VKG). MATERIALS AND METHODS: HSV system was used to capture images of vocal folds. HSV images were post-processed in Kay image-process software (KIPS), and conventional DKG images were retrieved. Custom-made post-processing system was used to convert HSV images to 2D-DKG images. The quantitative parameters of the post-processed 2D-DKG images was validated by comparing these parameters with those of the DKG images. RESULTS: Serial HSV images for all phases of vocal fold vibratory movement are included. The images were converted by the scanning method using U-medical image-process software. Similar to conventional DKG, post-processed 2D DKG image from the HSV image can provide quantitative information on vocal fold mucosa vibration, including the various vibratory phases. Differences in amplitude symmetry index, phase symmetry index, open quotient, and close quotient between 2D-DKG and DKG were analyzed. There were no statistical differences between the quantitative parameters of vocal fold vibratory movement in 2D-DKG and DKG. CONCLUSION: The post-processing method of converting HSV images to 2D DKG images could provide clinical information and storage economy.

The Characteristics of Musical Formant and Vocal Fold Vibration in the Classical and Western-Style Singers / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Professional singers have a particular "ringing" sound quality during singing, so called singer's formant. Two types of professional singers in Korea that sound very different are classical (pansori) and western style performers. The purpose of this research was to systematically analyze and compare the acoustic sound structure of both the speaking and singing voices of Korean classical singers (pansori). We also investigated the morphologic and vibratory characteristics of vocal folds using videostroboscopy. MATERIALS AND METHODS: 24 classical singers and 29 western style singers were subjects. The formant frequencies, intensities and singing power ratio was evaluated for clarifying the existence of singing formant. Using laryngeal stroboscopy, the vibratory characteristics were evaluated. RESULTS: The all formant intensities were incraesed in the classical singers, but typical increase of third and fourth formant in the western style singers. The singing power ratio was smaller in the western style singers. Most of classical singers showed abnormal vibratory patterns. CONCLUSION: The western style singers have typical singing formant during singing, but not in the classical singers. Most of classical singers showed abnormal vibratory patterns of vocal folds during phonation, but usually normal vibration in the western style singers.

Clinical Application of Videokymography / 听力学及言语疾病杂志

Objective To study the results of clinical application of videokymography. Methods 50 patients with voice pathology and 5 normal voice persons were studied with videokymography. Results With videokymography, left - right asymme- tries, close or open quotient differences, abnormal periocity and mucosal waves were visualized in 50 patients. The vibration of vo- cal folds was slight asymmetry in 1 normal voice person and normal in other 4 normal voice persons. Conclusion Videokymography provides a simple way to study irregular vibrations of the vocal folds. It is helpful for a more accurate diagnosis of the vocal folds. Information obtained allows a first time quantification of vibrations registered.

Variation of Electroglottographic Parameters with Different Frequency in Chest Register of Normal People / 听力学及言语疾病杂志

Objective To study the variable orderliness of vocal fold vibration caused by the voice with different frequency in chest register of various healthy subjects having several age and sex through electroglottographic examination.Methods 120 healthy subjects were respectively evaluated with electroglottography, including the old group, the adult group, the men group and the female group. Meanwhile the parameters of vocal fold vibration, such as the contact quotient, the contact index, the contact quotient perturbation and the contact index perturbation were measured and analyzed.Results With increase of the frequency, the contact quotient was decreased in all subjects, having signification difference. The contact quotient of old group and adult group ,men and female group had also signification difference. But other parameters not represented the difference in statistics.Conclusion The closer degree of vocal fold was varied with the different frequency in chest register voice from the healthy subjects who were different in age and sex ,but the symmetry and regulation of vocal fold vibration were not related to age and sex. The results were help to study physiology of vocal fold.