Nasal morphology significantly varies across different geographic regions and populations, necessitating distinct approaches in rhinoplasty surgery. Augmentation procedures are typically required among individuals of Southeast Asian and African descent, whereas reduction techniques are more frequently employed for populations from the Middle East and Northeast Asia, including Türkiye.1,2 Augmentation rhinoplasty typically has minimal impact on the internal nasal valve region and may even improve nasal patency. Conversely, substantial hump reduction commonly leads to a notable decrease in both the cross-sectional area and angle of the internal nasal valve.3 These anatomical alterations may consequently affect nasal airflow dynamics and critical voice parameters. One of the primary methods to mitigate such changes in structural rhinoplasty is the application of spreader grafts,3 which serve to prevent cosmetic deformities (e.g., inverted-V deformity, dorsal narrowing) as well as functional impairments (e.g., hyponasality, altered voice timbre, nasal obstruction).

Human voice production results from a complex interaction between the lungs, vocal cords, and the upper airway.4 The process begins with expiratory airflow generated by the lungs, which induces vocal cord vibrations through changes in transluminal pressure. This phenomenon, explained by the Bernoulli principle, generates the fundamental Frequency (F0) of the voice.5,6 In the subsequent phase, the final unique quality of the voice is shaped by the resonant properties of the sub-regions of the upper airway, including the pharynx, tongue, soft palate, nasal cavity, and paranasal sinuses. Surgical interventions involving these anatomical regions are expected to influence voice resonance characteristics. This assumption has been partially supported by previous studies.7–12 However, the effects of various surgical interventions on the upper airway, specifically on formants (spectral peaks), which serve as measurable indicators of upper airway-related resonance characteristics in human voice, have not yet been fully elucidated.13,14 While these potential changes may not significantly impact overall quality of life, they can present performance challenges for professional voice users such as singers and actors.14 If the performed surgery is purely cosmetic, such as rhinoplasty, voice alterations may lead to serious medicolegal consequences. A review of the literature concerning medicolegal issues related to complications of rhinoplasty and informed consent reveals a lack of consideration for voice changes.15–17 Additionally, the importance of higher formants, particularly F3, F4, and F5, in the formation of the singer’s and actor’s formant clusters should not be overlooked.18,19 Narrowing of the nasal cross-sectional area following cosmetic rhinoplasty may affect these formant clusters, especially during the production of nasalized syllables, posing significant performance challenges for professional voice users.

Although several studies have investigated the effects of nasal surgery on human voice, no prospective controlled study has specifically examined the protective effect of spreader grafts on voice alterations in purely cosmetic rhinoplasty.20–29 In this study, we aimed to determine whether the application of spreader grafts in cosmetic structural rhinoplasty could prevent adverse changes in human voice, particularly in the production of nasalized syllables.

In this study, we investigated the impact of spreader grafts in rhinoplasty on voice outcomes by comparing patients who underwent rhinoplasty with spreader grafts to those without. Our findings indicate that incorporating spreader grafts can produce notable differences in both acoustic (spectrographic) and subjective voice characteristics compared to rhinoplasty performed without spreader grafts. Spectrographic analysis, particularly of the nasalized word /mini/, revealed statistically significant variations in a greater number of acoustic parameters among patients without spreader grafts. Specifically, in cases lacking spreader grafts, significant changes were detected in fundamental voice parameters such as ShdB and jitter, as well as in the third (F3) and fourth (F4) formants of the consonants /m/ and /n/, and in the second formant (F2) of the consonant /n/. Conversely, patients who received spreader grafts showed significant acoustic changes exclusively in the third and fourth formants (F3 and F4) of the consonant /m/.

The production of the nasalized syllables in the word /mini/, especially its consonants /m/ and /n/, requires maintaining closure of the oral cavity, allowing sound to resonate through the sinonasal passages. It is well-documented in the literature that anatomical alterations within these regions can influence nasal resonance, thereby affecting voice perception.4 Our findings not only support this theory but also suggest that spreader grafts have a protective role in preserving certain objective voice parameters. Moreover, subjective patient perception, assessed via the VHI-10 score, demonstrated no significant postoperative changes among patients who received spreader grafts. In contrast, a significant increase in the VHI-10 scores was observed in patients without spreader grafts, further underscoring the beneficial effect of spreader grafts on patient-perceived voice outcomes.

The frequencies of the first (F1) and second (F2) formants correlate primarily with vowel identity, while higher formants such as F3 and F4 significantly influence the unique quality and timbre of an individual's voice.33 Variations in tongue position, soft palate elevation, and lip shape alter these frequencies, which is essential for accurate vowel perception. According to our study, the absence of significant postoperative changes in F1 and F2 in both patient groups indicates that vowel articulation was preserved. However, alterations in F3 and F4 frequencies and elevated VHI-10 scores in patients without spreader grafts suggest rhinoplasty can influence perceptions of hyponasality and individual voice timbre. This potential impact warrants particular attention, especially for professional voice users. The notable F3 and F4 changes in patients without spreader grafts, specifically during articulation of /m/ and /n/ consonants, are significant given their possible effect on the “singer’s formant cluster”, a convergence of the third, fourth, and occasionally fifth formants.14,18,19,34

The singer’s formant cluster is characterized by a spectral peak around 3000 Hz, created by deliberate modifications in vocal tract resonance, such as lowering the larynx, typically achieved through vocal training.30 This cluster allows a singer’s voice to project over orchestral accompaniment without extra vocal effort or strain, enhancing brightness and clarity. Similar resonant convergence, termed the “speaker’s formant cluster”, is also crucial in acting performances.19 Based on our results, the protective effect of spreader grafts on F3 and F4 parameters in structural rhinoplasty indicates their role in preserving the integrity of the singer’s and speaker’s formant clusters, particularly benefiting professional voice users such as singers and actors.

Another expected voice change following rhinologic surgery is altered nasality perception. Thus, the protective effect of spreader grafts on specific fundamental and spectrographic voice parameters noted in our study may also hold significance regarding nasality perception. However, literature suggests that nasality perception might be more closely associated with reductions in formant amplitude rather than frequency changes.20 Consequently, the lack of amplitude analysis in formant assessments constitutes a limitation of our study. Additionally, interindividual variations in nasal deformities and cross-sectional nasal areas introduce inherent variability to the results. Nevertheless, given our substantial sample size and the implementation of double-blind randomization, we believe we have effectively minimized this potential bias. Because our primary focus was voice outcomes, we did not prospectively or statistically compare aesthetic satisfaction between groups, so we cannot link the favorable voice profile of the spreader graft group to cosmetic results. No graft-related cosmetic complaints were noted, but this was not evaluated with validated aesthetic measures, despite their expected structural aesthetic benefits.

The importance of the upper respiratory tract, particularly the nasal cavity and paranasal sinuses, in vocal resonance is widely acknowledged.10,13,23,35–39 Rhinologic surgeries are expected to significantly affect vocal resonance characteristics, especially during the production of nasalized syllables, which was the primary focus of our investigation. Previous studies, including our own, have demonstrated that septoplasty and turbinate surgery ‒ other rhinological procedures ‒ particularly influence the F3 and F4 formants.

Relying solely on subjective and objective voice assessments may not fully capture nasality-related voice changes resulting from rhinologic surgery and alterations in nasal cavity patency. Therefore, spectrographic analysis of formants during the production of nasalized vowels is essential.22,21 In a previous study, we conducted spectrographic analyses to evaluate formant frequencies in cases undergoing septoplasty and turbinoplasty ‒ two commonly performed rhinologic procedures ‒ and identified statistically significant changes.14

Studies evaluating the effects of different rhinologic surgeries on voice using spectrographic analysis date back to 1997.9 However, these studies predominantly focused on functional nasal pathologies such as nasal polyposis, septoplasty, and endoscopic sinus surgery, where improvements in nasal patency typically enhance both voice quality and nasality.22,26–29 Conversely, primary structural rhinoplasty performed solely for cosmetic purposes involves patients without preoperative nasal obstruction or hyponasality, and thus the primary objective should be preserving existing voice quality. This distinction makes cosmetic rhinoplasty uniquely relevant regarding its potential postoperative voice alterations.14

Studies specifically examining rhinoplasty’s impact on voice remain limited.25,40–43 Existing research primarily comprises cohort studies, case series, and cross-sectional studies with small sample sizes. To date, no prospective controlled study assessing rhinoplasty’s effect on voice has been reported. Regarding spreader graft use, only a cohort study by Celik et al., involving 20 patients, exists44 Celik et al. reported improved VHI-10 scores among patients receiving spreader grafts without significant changes in fundamental and spectrographic voice parameters, suggesting a protective effect. However, due to the lack of a control group, the evidence remains limited. Given our prospective, double-blind, controlled trial design, our study represents a unique and significant contribution to the literature.

This study uniquely contributes to the literature as the first prospective, double-blind, controlled trial assessing both subjective (VHI-10) and objective (acoustic/spectrographic) voice outcomes following rhinoplasty with or without spreader grafts. Our findings highlight the importance of preserving sinonasal anatomical integrity to maintain optimal vocal resonance, emphasizing the protective role of spreader grafts particularly for professional voice users. This study not only bridges a significant gap in the current rhinologic literature but also provides robust evidence supporting the integration of spreader grafts into rhinoplasty procedures, especially in patients for whom voice quality and resonance are critically important.

Written informed consent was obtained from every participant. A sample of the written patient consent form has been approved by the relevant ethics committee and can be obtained from the ethics committee upon request.

No external funding was used for this study. The surgical equipment and voice analysis software and equipment used for the patients included in the study were already available in our clinic, and no additional budget was required.

It was approved by the Manisa Celal Bayar University Faculty of Medicine Health Sciences Ethics Committee (protocol number: 20.478.486/1515).

The authors declare that all data are available in repository.