The analysis of speech is often involved in the evaluation of voice and the discrimination between disphonic and normophonic speakers. Most of the time, acoustic features of voice disorders are obtained from sustained vowels. However, sustaining speech sounds is considered to be less informative than speaking continuously. The objective of the project therefore is to monitor the voice timbre and vocal perturbations in connected speech. Vocal disperiodicities obtained are summarised by means of vocal features that report speech properties that are clinically relevant with regard to the assessment of a speaker's voice. The description of voice disorders owing to peripheral causes are also considered. L'analyse acoustique du signal de parole est souvent utilisée dans l'évaluation et la discrimination des voix pathologiques. Les mesures acoustiques utilisées pour caractériser les troubles de la voix sont extraites de voyelles soutenues. Cependant, la représentation basée sur les voyelles soutenues n'est pas toujours valide. L'estimation de paramètres à partir de la parole connectée semble plus adéquate. L'objectif de ce projet est le développement de méthodes permettant le suivi d'un locuteur au cours de la lecture d'un texte de longue durée. L'utilisation de méthodes applicables à des signaux non stationnaires est aussi envisagée. Le bruit estimé par les différentes méthodes permet de déterminer les indices pertinents utilisés dans la caractérisation des troubles de la voix du locuteur. La caractérisation de certains troubles vocaux dus à un problème neurologique périphérique, comme les voix dysarthriques, est aussi examinée. [The analysis of speech is often involved in the evaluation of voice and the discrimination between disphonic and normophonic speakers. Most of the time, acoustic features of voice disorders are obtained from sustained vowels. However, sustaining speech sounds is considered to be less informative than speaking continuously. The objective of the project therefore is to monitor the voice timbre and vocal perturbations in connected speech. Vocal disperiodicities obtained are summarised by means of vocal features that report speech properties that are clinically relevant with regard to the assessment of a speaker's voice. The description of voice disorders owing to peripheral causes are also considered. ]