Laryngeal and Vocal Characterization of Asymptomatic Adults With Sulcus Vocalis

THIEME Original Research Laryngeal and Vocal Characterization of Asymptomatic Adults With Sulcus Vocalis Alex Bruno Soares1 Bruno Teixeira de Moares1 Noemi Grigoletto de Biase3 Jonia Alves Lucena2 1 Department of Otorhinolaringology, Health Sciences Center, Universidade Federal de Pernambuco, Recife, PE, Brazil 2 Department of Fonoaudiology, Health Sciences Center, Universidade Federal de Pernambuco, Recife, PE, Brazil 3 Paulista Medical School, Department of Otorhinolayngology and Head and Neck Surgery, Universidade Federal de São Paulo, São Paulo, SP, Brazil Ana Nery Barbosa de Araújo2 Address for correspondence Alex Bruno Soares, MD, MSc, Rua Arnado de Albuquerque, 501, apto 1301, Lauritzen, Campina Grande, Paraíba, PB, 58401-390, Brazil (e-mail: ). Int Arch Otorhinolaryngol 2019;23:331–337. Abstract Keywords ► voice ► vocal cords ► voice quality Introduction Sulcus vocalis is defined as a longitudinal depression on the vocal cord, parallel to its free border. Its most marked characteristic is breathlessness, caused by incomplete glottal closure, in addition to roughness, due to the decrease in mucosal wave amplitude of the vocal cords. Vocal acoustic aspects, such as fundamental voice frequency, jitter, and shimmer, may also be altered in individuals with this type of laryngeal disorder. To assess the voice of individuals with sulcus vocalis, studies generally include a sample of subjects with vocal symptoms, excluding asymptomatic persons. To better characterize the vocal characteristics of individuals with sulcus vocalis, their asymptomatic counterparts must also be included. Objective Characterize the larynx and voice of asymptomatic adults with sulcus vocalis. Method A total of 26 adults, 13 with sulcus vocalis (experimental group) and 13 without (control group) were assessed. All the participants were submitted to suspension microlaryngoscopy, voice self-assessment, auditory perception and acoustic evaluation of the voice. Results Among the individuals with sulcus vocalis, 78% of the sulci were type I and 22% type II. Auditory perception assessment obtained statistically significant lower scores in individuals with sulcus vocalis compared with the control group, and a slight difference in the overall degree of hoarseness and roughness. No statistically significant intergroup diferences were found in self-reported voice or acoustic assessment. Conclusion Type I was the predominant sulcus vocalis observed in individuals without voice complaints, who may also exhibit slight changes in vocal quality and roughness. Introduction Several factors can interfere in vocal quality, including biological, psychological or socioeducational aspects.1 However, the Alex Bruno Soares’s ORCID is https://orcid.org/0000-0001-58351514. received October 9, 2018 accepted March 17, 2019 DOI https://doi.org/ 10.1055/s-0039-1688457. ISSN 1809-9777. morphological dimension of the speech apparatrus, especially the larynx, has a significant influence on voice characteristics.1,2 Although there is a supposed anatomical model of the larynx that represents the symmetry of its halves, and vocal cords with a uniform and stratified surface in the epithelium, lamina propria with three distinct layers and vocal muscle, this Copyright © 2019 by Thieme Publicações Ltda, Rio de Janeiro, Brazil 331 332 Laryngeal and Vocal Characterization Soares et al. conformation seems not to be found in the entire population.3 Small anatomical alterations in the larynx, such as the sulcus vocalis, can change its functional result, predisposing individuals to dysphonia (hoarseness) or vocal fatigue.1,2,4 The sulcus vocalis is defined as a longitudinal depression in a vocal cord parallel to its free border, which can vary in extension and depth, and be unilateral or present in both vocal cords. Histologically, the sulcus is located on the surface layer of the lamina propria and is lined with the stratified epithelium, contiguous to the epithelium with a normal mucosal lining.2 Sulcus changes are classified according to their morphological characteristics and the degree to which the vocal cord structures are compromised. Ford et al (1996)5 divided sulcus disorders of the vocal folds into 3 groups: In type I, epitelial invagination is limited to the lamina propria; type II, epithelial invagination along the vocal fold length; type III is the true sulcus vocalis (pocket type) and represents an epithelial invagination that may penetrate into the vocal ligament and/or vocalis muscle layers. Pontes et al (1994)2 propose the following categories: sulcus stria minor—epithelial invagination, whose upper and lower lips usually touch each other; sulcus stria major— spindle-shaped mucosal depression, with a stiffer consistency and adhering to deeper structures, such as the vocal ligament and muscle; pouch-shaped sulcus—lesion that emerges as an invagination, whereby its lips touch each other and the opening leads to a dilated pouch-shaped subepithelial space. The real incidence of sulcus vocalis is unknown, due to three factors: lack of knowledge of this laryngeal alteration, diagnostic error, or the absence of diagnosis when vocal symptoms are not serious enough to cause vocal complaints.6 Currently, examinations such as videolaryngoscopy, videolaryngostroboscopy or suspension microlaryngoscopy are used to investigate morphological and structural changes in the vocal cords, although it is important to consider the data related to the clinical history of vocal alterations.1,6–9 It is important to underscore that the sulcus vocalis is not always evident in videolaryngoscopy and often causes only slight structural alterations, although the vocal repercussions can be considerable.2,6–8 Videolaryngostroboscopy can help assess a larynx with sulcus vocalis, showing a decline or absence of mucosal wave vibration.1,9 However, under some circumstances, an accurate diagnosis of the sulcus vocalis can only be obtained by suspension microlaryngoscopy, the gold standard for diagnosing minimal structural changes. It is applied exceptionally because of its invasive nature and the fact that the procedure is performed under general anesthesia.8,9 Suspension microlaryngoscopy makes it possible to assess vocal cord details under binocular microscopy at depth and with good lighting, enabling the use of instruments for palpating vocal cord alterations and providing an important contribution to sulcus vocalis diagnosis.8,9 With respect to characterizing visual laryngeal, auditory perception and acoustic attributes, studies performed with symptomatic individuals show that most vocal sulci are bilateral, with types II and III being the most common.5,10–12 The most marked vocal characteristic of this lesion is breathlessInternational Archives of Otorhinolaryngology Vol. 23 No. 3/2019 ness, which results from incomplete glottal closure. Another vocal parameter is roughness, due to the decline in mucosal wave vibration in the vocal cords.1, (...truncated)