Common Vocal Effects and Partial Glottal Vibration in Professional Nonclassical Singers.

OBJECTIVE: To multidimensionally investigate common vocal effects in experienced professional nonclassical singers, to examine their mechanism of production and reproducibility, to demonstrate the existence of partial glottal vibration, and to assess the potential of damage to the voice from nonclassical singing. STUDY DESIGN: Individual cohort study. METHODS: Ten male singers aged between 25 and 46 years (34 ± 7 years [mean ± SD]) with different stylistic backgrounds were recruited (five pop/rock/metal, five musical theater). Participants repeatedly presented the usual nonclassical vocal effects and techniques in their repertoire. All performances were documented and analyzed using established instruments (eg, auditory-perceptual assessment, videolaryngostroboscopy, electroglottography, voice function diagnostics). RESULTS: The vocal apparatus of all singers was healthy and capable of high performance. Typical nonclassical vocal effects were breathy voice, creaky voice, vocal fry, grunting, distortion, rattle, belt, and twang. All effects could be easily differentiated from each other. They were intraindividually consistently repeatable and also interindividually produced in a similar manner. A special feature in one singer was the first evidence of partial glottal vibration when belting in the high register. The unintended transition to this reduced voice quality was accompanied by physical fatigue and inflexible respiratory support. CONCLUSION: The long-lasting use of the investigated nonclassical vocal effects had no negative impact on trained singers. The possibility of long-term damage depends on the individual constitution, specific use, duration, and extent of the hyperfunction. The incidence of partial glottal vibration and its consequences require continuing research to learn more about efficient and healthy vocal function in nonclassical singing.

Efficacy of Phonosurgery, Logopedic Voice Treatment and Vocal Pedagogy in Common Voice Problems of Singers.

INTRODUCTION: Functional and organic impairments of the singing voice are common career-threatening problems of singers presenting in phoniatric and laryngological departments. The objective was to evaluate the efficacy of phonosurgery, logopedic voice treatment and vocal pedagogy in common organic and functional voice problems of singers, including investigation of the recently introduced parameter vocal extent measure (VEM). METHODS: In a prospective clinical study, the analysis of treatment outcome in 76 singers [57 female, 19 male; 38 ± 11 years (mean ± SD)] was based on pre- and post-therapeutic voice function diagnostics and videolaryngostroboscopy. Examination instruments included auditory-perceptual voice assessment, voice range profile (VRP), the VEM calculated from area and shape of the VRP, acoustic-aerodynamic analysis, and patients' self-assessment (e.g., Singing Voice Handicap Index). RESULTS: While 28% of all singers (21/76) presented with functional dysphonia, 72% (55/76) were diagnosed with organic vocal fold changes, of which marginal edema (n = 25), nodules (n = 9), and polyps (n = 8) were the most common pathologic changes. Of the 76 singers, 57% (43) received phonosurgery, 43% (33) had conservative pedagogic (14) and logopedic (19) treatment. Three months post-therapeutically, most parameters had significantly improved. The dysphonia severity index (DSI) increased on average from 6.1 ± 2.0 to 7.4 ± 1.8 (p < 0.001), and the VEM from 113 ± 20 to 124 ± 14 (p < 0.001). Both parameters correlated significantly with each other (rs = 0.41). Phonosurgery had the largest impact on the improvement of vocal function. Conservative therapies provided smaller quantitative enhancements but also qualitative vocal restoration with recovered artistic capabilities. CONCLUSIONS: Depending on individual medical indication, phonosurgery, logopedic treatment and voice teaching are all effective, objectively and subjectively satisfactory therapies to improve the impaired singing voice. The use of VEM in singers with functional and organic dysphonia objectifies and quantifies their vocal capacity as documented in the VRP. Complementing the established DSI, VEM introduction into practical objective voice diagnostics is appropriate and desirable especially for the treatment of singers.