Patrick Schlegel1, Michael Stingl2, Melda Kunduk3, Stefan Kniesburges4, Christopher Bohr5, Michael Döllinger4. 1. FAU Erlangen-Nürnberg, Medical School, Division of Phoniatrics and Pediatric Audiology at the Department of Otorhinolaryngology Head & Neck Surgery, University Hospital Erlangen, Erlangen, Germany. Electronic address: Patrick.Schlegel@uk-erlangen.de. 2. Department Mathematics, Applied Mathematics II, FAU Erlangen-Nürnberg, Erlangen, Germany. 3. LSU Speech Language Hearing Clinic, Department of Communication Sciences & Disorders, Louisiana State University, Baton Rouge, Louisiana. 4. FAU Erlangen-Nürnberg, Medical School, Division of Phoniatrics and Pediatric Audiology at the Department of Otorhinolaryngology Head & Neck Surgery, University Hospital Erlangen, Erlangen, Germany. 5. FAU Regensburg, Clinic and Polyclinic for Otolaryngology, University Hospital Regensburg, Regensburg, Germany.
Abstract
OBJECTIVE: The phonatory process is often judged during sustained phonation by analyzing the acoustic voice signal and the vocal fold vibrations. Many formulas and parameters have been suggested for qualifying the characteristics of the acoustic signal and the vocal fold vibrations during sustained phonation. These parameters are directly computed from the acoustic signal and the endoscopic glottal area waveform (GAW). The GAW is calculated from laryngeal high-speed videoendoscopy (HSV) recordings and describes the increase and decrease of the glottal area during the phonation process, that is, the opening and closing of the two oscillating vocal folds over time. However, some of the parameters have strong mathematical dependencies with one another and some are ill-defined. The purpose of this study is to identify mathematical dependencies between parameters with the aim of reducing their numbers and suggesting which parameters may best describe the properties of the GAW and the acoustical signal. METHODS: In this preliminary investigation, 20 frequently used parameters are examined: 10 GAW only and 10 both GAW and acoustic parameters. RESULTS: In total 13 parameters can be neglected because of mathematical dependencies. In addition, nine of these parameters show problematic features that range from unexpected behavior to ill definition. CONCLUSIONS: Reducing the number of parameters appears to be necessary to standardize vocal fold function analysis. This may lead to better comparability of research results from different studies.
OBJECTIVE: The phonatory process is often judged during sustained phonation by analyzing the acoustic voice signal and the vocal fold vibrations. Many formulas and parameters have been suggested for qualifying the characteristics of the acoustic signal and the vocal fold vibrations during sustained phonation. These parameters are directly computed from the acoustic signal and the endoscopic glottal area waveform (GAW). The GAW is calculated from laryngeal high-speed videoendoscopy (HSV) recordings and describes the increase and decrease of the glottal area during the phonation process, that is, the opening and closing of the two oscillating vocal folds over time. However, some of the parameters have strong mathematical dependencies with one another and some are ill-defined. The purpose of this study is to identify mathematical dependencies between parameters with the aim of reducing their numbers and suggesting which parameters may best describe the properties of the GAW and the acoustical signal. METHODS: In this preliminary investigation, 20 frequently used parameters are examined: 10 GAW only and 10 both GAW and acoustic parameters. RESULTS: In total 13 parameters can be neglected because of mathematical dependencies. In addition, nine of these parameters show problematic features that range from unexpected behavior to ill definition. CONCLUSIONS: Reducing the number of parameters appears to be necessary to standardize vocal fold function analysis. This may lead to better comparability of research results from different studies.
Authors: Patrick Schlegel; Melda Kunduk; Michael Stingl; Marion Semmler; Michael Döllinger; Christopher Bohr; Anne Schützenberger Journal: PLoS One Date: 2019-04-22 Impact factor: 3.240
Authors: Patrick Schlegel; Andreas M Kist; Melda Kunduk; Stephan Dürr; Michael Döllinger; Anne Schützenberger Journal: PLoS One Date: 2021-02-02 Impact factor: 3.240