Voice Disorder Classifications: A Scoping Review—Part B

Abstract

The terminology and classification of voice disorders are complex topics. For this reason, developing a consensus in the scientific community regarding such a topic would bring a wide range of benefits to this field of study. The study is originally divided into parts A and B, and part A explored general propositions of voice disorder classification systems. Now, Part B of this study explores the classification of voice disorders in specific conditions and diagnoses. A scoping review was performed after an electronic and manual search, resulting in the inclusion of 20 studies in Part B. The articles were published between 1993 and 2020, most of which originated from the United States. The specific conditions covered by the studies were muscle tension dysphonia (MTD), spasmodic dysphonia, dystonias, and psychogenic voice disorders, among others. The terminology used to refer to these conditions, especially when hyper-functional aspects of the larynx are involved also varied. Six studies proposed classification systems, while another 14 studies discussed classifications and/or stressed the need for additional studies regarding laryngeal conditions such as these. Among the studies that proposed classification methods, the number of groups varied between two and six, with MTD being the most studied condition. In conclusion, recent studies seek to reduce the number of classifying categories in voice disorders, despite understanding the specificity of wide-ranging clinical profiles. Disorder etiology is the foundation for these proposals. In Part B of this study, specific diagnoses of voice and laryngeal conditions are shown to be classified with a descriptive and visual approach, such as an examination of the larynx. Technological evolution can improve voice and laryngeal semiotics and lead to more automated classification of voice disorders.