Methods used in morphometric analysis of singers’ vocal tracts: an integrative review

Abstract

Purpose To describe the main quantitative methods used for morphometric analysis of the vocal tract in singers, their applications and the main segments studied. Research strategy This is an integrative review guided by the guiding question “What are the main quantitative methods used for morphometric analysis of the vocal tract, their applications and the main segments studied in singers?”. The electronic databases PubMed, Scopus and VHL were used through the search key (Vocal tract OR Oropharynx) AND (Morphology OR Geometry) AND (Evaluation OR Diagnosis) AND (voice), without restriction of years of publication, including articles in three languages: Portuguese, English and Spanish. Selection criteria The selection took place independently through reading by pairs and subsequent application of exclusion and inclusion criteria. Results Of the 380 studies, 30 duplicates were excluded. After reading the abstracts, applying the selection criteria, 18 studies were selected for full reading, of which 12 were included in this review. Magnetic resonance imaging was the main instrument used and the analyzed segments ranged from the length and volume of the vocal tract to isolated segments and their morphological particularities. Conclusion Vocal tract morphological quantification methods are important for the instrumental evaluation of the vocal tract and its segments, a technological update leading to better understanding of singers’ voice and therapeutical intervention.