INVITED ARTICLE


https://doi.org/10.5005/jp-journals-10001-1448
International Journal of Head and Neck Surgery
Volume 12 | Issue 3 | Year 2021

Gender Affirming Voice Care: A Literature Review


Joseph Chang1, Katherine Yung2

1Department of Head and Neck Surgery, The Permanente Medical Group, Santa Clara, California, USA

2San Francisco Voice & Swallowing, San Francisco, California, USA

Corresponding Author: Department of Head and Neck Surgery, The Permanente Medical Group, Santa Clara, California, USA, Phone: 408-851-2950, e-mail: josephbchang@gmail.com

ABSTRACT

Aim and objective: Review recent advances and understanding of gender affirming voice care

Background: Treatment for gender dysphoria is increasingly recognized as medically necessary. Voice care is similarly as important as treatments focused on physical change.

Review results: This article reviews gender cues in communication as well as voice care options for voice masculinization and feminization. Voice masculinization techniques are poorly researched due to expectations that hormone replacement therapy (HRT) will result in adequate masculinization. HRT results are variable, however, and voice therapy and surgery are secondary options. Voice feminization has been better studied. While voice therapy and voice surgery are both options, voice therapy is often pursued first due to a low risk profile. Nonetheless, voice surgery techniques including Wendler glottoplasty (WG) and its variations are effective and safe.

Conclusion: Gender affirming voice care is critical in the treatment of gender dysphoria. HRT is often inadequate for voice masculinization. Further research in voice therapy and surgery options is needed. In voice feminization, voice therapy and voice surgery, particularly WG, have been effective in improving not only vocal pitch but also quality of life.

Clinical significance: Transgender individuals constitute a significant proportion of the population and frequently suffer from gender dysphoria. Gender affirming voice care is an essential component of treating gender dysphoria.

How to cite this article: Chang J, Yung K. Gender Affirming Voice Care: A Literature Review. Int J Head Neck Surg 2021;12(3):93-97.

Source of support: Nil

Conflict of interest: None

Keywords: Gender dysphoria, Hormone replacement therapy, HRT, Laryngoplasty, Trans voice, Vocal fold shortening and retrodisplacement of the anterior commissure (VFSRAC), Voice surgery, Voice therapy, Wendler.

BACKGROUND

Transgender individuals experience a discordance between their own personal sense of gender and the sex assigned to them at birth. These individuals comprise a sizeable, 0.5–1.2% of the total population.1 Gender dysphoria is the term used to describe the distress from misalignment of self-identified and assigned gender. Treating gender dysphoria has been associated with decreased suicide attempt rates,2 improved quality of life,2,3 and increased rate of employment2 and pursuit of higher education.4 Given these health and socioeconomic benefits, insurance coverage for transgender services has been found to be cost effective,5 with an insignificant economic cost,6,7 and has been found to be medically necessary by numerous major medical associations including the American Medical Association (AMA),8 American Psychiatric Association (APA),9 American Academy of Family Physicians (AAFP),10 American Academy of Pediatrics (AACP),11 and American College of Obstetricians and Gynecologists (ACOG).12

While treatment for gender dysphoria has been available since the second half of the 20th century,13 recognition of the healthcare needs of this population have been increasing in more recent years. From 2012 to 2017, 12 states and the District of Columbia expanded their Medicaid coverage to include transition-related care.14 Additionally, the percent of Fortune 500 companies that have included transgender-inclusive health insurance has increased from 0% in 2009 to 71% in 2021.15

While many gender affirming treatments focus on physical appearance, voice and communication are similarly important to gender transition. In a national survey of 27,700 transgender individuals, 66 and 48% of transgender women respondents have had or want vaginoplasty or facial feminization surgery, respectively, compared to 62% of transgender women respondents who have had or want voice therapy.16

This article reviews the recent advances and understanding of gender affirming voice care with a focus on voice surgery.

GENDER CUES IN COMMUNICATION

High and low vocal pitch are commonly identified as indicators of masculinity and femininity. Normative ranges for pitch vary by source, with fundamental frequency of cisgender men and women generally in the range of 100–120 and 190–220 Hz, respectively. However, pitch is only one of many qualities known to affect gender identification and has been found to account for only 42% of variance in perception of speaker gender.17

Additional factors found to affect perception of gender according to research without high risk of bias include resonance, which describes the filtering effect of the upper aerodigestive tract on voice, articulation patterns, and intonation.17

Multiple gender communication cues must be addressed to effectively change gender perception. As an example, accurate gender identification in digitally modified voice samples was shown to fall to less than 34% when pitch and resonance were incongruent.18

APPROACH TO TREATMENT

Arguably more important than perceived vocal femininity or masculinity is the effect that treatment has on individuals’ quality of life. Normative ranges and qualities exist for stereotypical male and female voices; however, these characteristics may not be congruent with every patient’s own self-perception. Ultimately, quality of life has been shown to correlate with patients’ perception of their own voice rather than the perception of listeners.19 As a result, treatment options may need to be adjusted for every patient to optimize outcomes.

In general, there are two treatment options for voice alteration, voice therapy and voice surgery. Voice therapy is able to address multiple communication cues and is noninvasive, whereas voice surgery primarily addresses pitch, is invasive, and therefore has associated small but significant medical risks. Consideration of risks and benefits in this situation often favors voice therapy as the first treatment for voice adjustment.

VOICE MASCULINIZATION

Voice care for transgender men has been relatively less studied than care for transgender women due to the masculinizing effects of hormone replacement therapy (HRT) involving androgens. Multiple longitudinal studies have confirmed that fundamental frequency decreases within the first 12 months of starting HRT.20,21 However, the effect of HRT on voice is quite variable with ultimate decrease in pitch varying from 3 to 10 semitones in one prospective study and the onset of pitch decrease starting anywhere from 0 to 6 months after initiating HRT.20

Unfortunately, voice change from HRT is not without risk. A meta-analysis of transgender men who underwent HRT found that 37% developed vocal instability and 27% lost vocal endurance.22 A retrospective study of 50 patients showed that 24% sought voice therapy while on HRT due to voice problems including vocal fatigue, instability, and strain with 10% seeking voice therapy for insufficient pitch lowering.21 Another meta-analysis confirmed that 16% of transgender patients undergoing testosterone therapy were not satisfied with their voice after hormone treatment.23

While voice therapy for voice masculinization is cited as a treatment option for patients with inadequate improvement after HRT, little data exist on the outcomes of voice therapy in the transgender male population.22 However, one study of 10 transgender men showed successful decrease in pitch after voice therapy with steady improvement in the self-perceived overall vocal masculinity up to 12 months after therapy.24

Surgery for pitch depression has been described using the type III thyroplasty, or relaxation laryngoplasty. In this surgery, pitch is decreased by shortening the vocal folds and reducing vocal fold tension. This can be performed by vertically incising both thyroid alae and depressing the central segment of thyroid cartilage containing the anterior vocal fold attachments to decrease the anteroposterior dimensions of the laryngeal framework. While type III thyroplasty has been described in mutational falsetto,25,26 only case reports of this surgery in transgender men have been published.27

VOICE FEMINIZATION

Unlike hormone therapy for transgender men, hormone therapy for transgender women does not result in voice change. As a result, the treatments for voice feminization in the transgender population are more commonly pursued and better understood.

VOICE THERAPY

Voice therapy approaches vary widely with common targets including resonance, speaking pitch elevation, relaxation techniques, and intonation.28 Although this variation in approaches complicates standardized evaluation of voice therapy, a number of studies have shown that voice therapy is effective at improving listener perception of vocal femininity,29 self-rating of vocal femininity,30 satisfaction with voice,30 and quality of life.31

Yet, listener perception of vocal femininity29 and pitch elevation29,32 may not be maintained long term after voice therapy ends. A small study of five transwomen undergoing voice therapy showed that the initial average post-treatment pitch elevation of 59 Hz had decreased to 19 Hz by 15 months after therapy.29

VOICE SURGERY

Despite voice therapy, a number of individuals continue to have difficulty achieving or maintaining a desired pitch and choose to have additional surgical treatment. The percentage of individuals who choose to undergo surgery after voice therapy will certainly vary by center with those centers that offer voice surgery undoubtedly attracting a higher proportion of patients who will ultimately pursue surgery. Nonetheless, demand for surgery is considerable with 19% of patients in a national survey of transgender women showing interest in voice surgery,16 and an estimated 20% of transgender women who had completed voice therapy at one center going on to have voice surgery.33

Numerous surgeries have been developed for voice feminization. These surgeries include techniques to decrease vocal fold mass (laser reduction glottoplasty34,35), increase vocal fold tension [cricothyroid approximation (CTA)], and shorten vocal fold length [Wendler glottoplasty (WG) and feminization laryngoplasty36,37]. Among these surgeries WG and CTA may be the best studied in the literature.

CRICOTHYROID APPROXIMATION

Cricothyroid approximation (CTA) is an open surgical technique in which the anteroinferior edge of the thyroid cartilage is brought into apposition with the anterior cricoid body with nonabsorbable sutures to recreate the vocal fold elongating effect of the cricothyroid muscle, thereby fixing the vocal folds in a permanently tensed state.

Multiple studies have confirmed successful elevation of pitch after CTA with reports ranging from 23 to 76 Hz.38,40 Variation in reported pitch elevation may result from differences in evaluated voice samples, for example, sustained vowels versus standardized passage reading or spontaneous speech. Additional factors more specific to pitch variation after CTA include patient anatomy and time since surgical intervention. Cricothyroid joint configuration has been found to correlate with achievable pitch elevation with well-defined joints, type A joints, having greater pitch elevation than poorly defined or absent joints, type B and C joints.39

Additionally, two longitudinal studies of CTA have shown that pitch elevation effects are not durable on long-term follow-up. One study of 20 patients noted a 73 Hz pitch elevation at 6 months, which then dropped to 46 Hz at 24 months after surgery.40 Another study of 29 patients reported a 42 Hz pitch elevation at 6 months that fell to 23 Hz at 12 months with continued decreases in pitch elevation through the 4-year study period.38

Arguably more important than pitch elevation, quality of life, as measured by voice handicap index (VHI), has been found to improve after CTA.38 However, it is not clear that VHI adequately measures voice-related quality of life in the transgender population, potentially because anatomic abnormalities are not the cause of reduced quality of life in this population. In one study, despite being regularly misgendered on the phone, transgender participants had no disability on VHI.41 The trans woman voice questionnaire (TWVQ), previously known as the transsexual voice questionnaire (TVQ), has been developed and validated specifically to measure voice-related quality of life in the transgender woman population.42,44 To our knowledge, no studies have reported TWVQ results following CTA.

WENDLER GLOTTOPLASTY

Wendler glottoplasty is a minimally invasive, endoscopic technique in which the medial aspects of the anterior vocal folds are denuded and sutured together (Fig. 1) to create an anterior glottic web (Fig. 2), thereby shortening the length of the vocal fold that is involved in vibration. Of note, there are slight variations to this technique including vocal fold shortening and retrodisplacement of the anterior commissure (VFSRAC), in which particular attention is paid to recreation of a tapered, funnel-shaped infraglottis to enhance smooth glottic air flow,45 as well another variation in which an additional step is taken to ablate the superior vocal fold surface, similar to laser reduction glottoplasty.38,46,47

Figs 1A to C: Wendler glottoplasty technique. Prior to incision (A), after removal of the anterior medial vocal fold mucosa (B), and after suturing the anterior vocal folds together at the completion of surgery (C).

Fig. 2: Wendler glottoplasty postoperative appearance. Well-formed anterior glottic web at 3 months after surgery.

Similar to CTA, numerous studies have reported successful pitch elevation following WG ranging from 20 to 81 Hz.38,45,47,48 Variation in these outcomes may be due to variation in patient age and an additional pitch elevation effect from postoperative voice therapy. The studies from Kim and Mastronikolis et al. included postoperative voice therapy and reported the higher pitch elevation outcomes of 74 to 81Hz.45,47 Although no comparative statistics were performed between age groups, these two studies also reported greater pitch elevation in patients younger than 40 years.45,47 However, a study excluding the effects of voice therapy showed no correlation with age and postoperative pitch or change in pitch.48

Unlike CTA, pitch elevation after WG appears to be long lasting and improvement in quality of life specific to transgender women after WG is well documented. One study of patients undergoing WG showed similar pitch elevation from the 1 month postoperative evaluation to the last follow-up time point at 4 years.38 Additionally, multiple studies have found improvement in TWVQ46,48 as well as VHI.38,45,48

In the current paradigm in which voice therapy is often pursued prior to voice surgery, some may consider voice surgery as an option only for those who “fail” voice therapy. On the contrary, a recent study of voice therapy compared to combined voice therapy followed by WG suggests that addition of WG further elevates pitch and improves quality of life even in those patients who objectively succeed after voice therapy. After voice therapy, patients who chose to pursue additional WG had no statistically significant difference in average speaking fundamental frequency or degree of pitch elevation compared to those who chose not to pursue additional WG, with 20 and 15 Hz elevations in pitch , respectively. Nonetheless, pitch elevation and improvement in TWVQ were nearly three times higher after combined treatment compared to voice therapy only.31

COMPARISON OF TECHNIQUES

Due to lack of standardization in voice measurements and timing of evaluations, comparisons between CTA and WG are best made by studies specifically designed to compare these two techniques with uniform methods. Two such studies exist. Mora et al. found that self-perceived femininity and pitch elevation were statistically higher in individuals who underwent WG compared to those who underwent CTA.38 Kelly et al. similarly reported statistically significant improvement in satisfaction with voice in individuals who underwent WG, but not those individuals who underwent CTA. Moreover, there was a significantly lower rate of self-reported dysphonia in patients who underwent WG compared to CTA. These findings in combination with the greater ability to revise WG than CTA led these authors to stop performing CTA at their institution in favor of WG.33

SURGICAL COMPLICATIONS

Historically, there have been concerns regarding the viability of voice surgery as a treatment for voice feminization due to reports of postsurgical dysphonia, dysphagia, and infection. 49 Indeed, CTA has been found to have a 7% rate of wound infection38 in one series and 29% rate of postoperative dysphagia in another series.40 On the other hand, those same series reported no change in voice quality on perceptual evaluation using the GRBAS (Grade, Roughness, Breathiness, Asthenia, Strain) score38 and a minimal change in average jitter from 0.6 to 0.7%.40

Wendler glottoplasty has a seemingly even lower rate of postoperative complications. While web dehiscence has been reported at rates of 5–13%,3138 no reports of postoperative infection or dysphagia have been identified on systematic review of the WG literature.50 Some data exist to suggest that glottoplasty causes postoperative dysphonia; a meta-analysis of three studies including 70 patients reported that auditory perceptual evaluation of overall voice quality graded on the GRBAS scale worsened by 0.44 after glottoplasty.50 This degree of worsening represents a half-step worsening on a four-point scale with gradations of normal, mild, moderate, and severe dysphonia; the clinical significance of this degree of change is unclear. Moreover, larger studies of objective acoustic measures show no worsening of dysphonia. In a series of 28 patients, no change in cepstral peak prominence, cepstral index of dysphonia, noise to harmonic ratio, or soft phonation index was detected after glottoplasty.48 Similarly, another study of 362 patients undergoing glottoplasty showed no change in noise to harmonic ratio and slight improvement in soft phonation index.45

Although arguments could be made regarding the sensitivity of perceptual evaluation versus acoustic measurements and the clinical significance of a 0.44 point worsening in dysphonia, it is possible that the difference in postoperative dysphonia may be related to differences in technique. The three studies utilized in the meta-analysis by Aires et al. that report worsening in perceptual measures of voice all report concomitant ablation of the superior vocal fold surface in addition to creation of an anterior glottic web,38,46,47 in essence a combination of laser reduction glottoplasty and WG. In contrast, the two previously cited studies showing no change in acoustic measures only created an anterior glottic web and did not ablate additional vocal fold tissue.45,48

While the risks and benefits of voice surgery compared to voice therapy can be debated, recent data shows that WG can be routinely performed with minimal morbidity with the acknowledgement that any surgery when performed poorly can result in serious complications.

CONCLUSION

Treatment for gender dysphoria is increasingly recognized as medically necessary. In addition to treatments focused on physical change, treatments for changing voice and communication are also essential. In the transgender male population, HRT is helpful in masculinizing the voice although its effects are variable. Unfortunately, voice therapy and voice surgery for voice masculinization is poorly understood and in need of further research. In the transgender female population, the efficacy of voice therapy and voice surgery is well documented in the literature, although approaches and techniques vary. Wendler glottoplasty has been shown to be a safe and durable intervention for voice feminization with minimal to no expected postoperative dysphonia.

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