Mette Pedersen MD, Sanila Mahmood, Anders Jønsson, Mohammad Shezad Mahmood, Bilal Hussain Akram, Anne Alexius Agersted
The purpose was to compare different quantitative methods to determine diagnoses of laryngeal disorders in a better way. Stroboscopy with its low amount of pictures of movements of the 25 pictures pr. second of vocal folds cannot show correct functions of the larynx. This paper evaluates high speed films with 4000 pictures per second, kymography with a graphical representation of spatial position over time of the vocal folds seen from above, calculation of stiffness of vocal folds based on phonovibrograms, phonetograms and software for overtones of the voice as usable tools. There are still many options. Stiffness measured with phonovibrograms is a mechanical measure for determining flexure of the vocal folds during movement. Combined with overtones it might be used to determine the treatment effect in voice pathology. They are easier to use than air flow and phonetograms and quantitatively correct.