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Impact of Perioperative Voice Therapy on Outcomes in the Surgical Management of Vocal Fold Cysts
ARTICLE IN PRESS Impact of Perioperative Voice Therapy on Outcomes in the Surgical Management of Vocal Fold Cysts Kathleen M. Tibbetts, Laura M. Dominguez, and C. Blake Simpson, San Antonio, Texas Summary: Introduction. Vocal fold cysts are benign mid-membranous lesions of the true vocal fold, classified as mucus retention or epidermal inclusion cysts. Treatment is surgical excision with or without postoperative voice therapy. Methods. A retrospective review was performed of the demographics, treatment approach, and outcomes of patients treated for vocal fold cysts between 2009 and 2014. Voice Handicap Index (VHI)-10 scores before and after treatment were compared using the Wilcoxon Rank-Sum test and the two-tailed Student’s t test. Videostroboscopy examinations were reviewed for posttreatment changes in vibratory characteristics of the vocal folds. Results. Twenty-five patients were identified, and one was excluded for incomplete records. Mean age was 41.9 years (66.7% female), and mean follow-up time was 5.58 months. Microflap excision was pursued by 21/24 (87.5%) patients, with 14 patients (58.3%) undergoing perioperative voice therapy. One cyst recurred. Two patients elected for observation, and their cysts persisted. VHI-10 decreased from 23.8 to 6.6 (P < 0.001) overall. There was a statistically significant reduction in VHI-10 in patients undergoing surgery with and without postoperative voice therapy (P < 0.004 and 0.001), but there was no significant difference between these two groups. Mucosal wave was classified as normal or improved in the majority. Cysts were characterized as mucus retention cysts in 19/21 (90%) and as epidermal inclusion cysts in 2/21 (10%). Conclusions. Vocal fold cysts impact mucosal wave and glottic closure. Surgical excision resulted in low rates of recurrence, and in improvement in the mucosal wave and VHI-10. Perioperative voice therapy did not offer a significant benefit. Mucus retention cysts were the majority, in contrast to other published studies. Key Words: Vocal fold cyst–Benign vocal fold lesion–Dysphonia–Voice therapy–Videostroboscopy. INTRODUCTION A vocal fold cyst is a benign mid-membranous lesion that typically presents as a sac-like structure with well-defined borders within the superficial lamina propria of the true vocal fold. They are estimated to account for 6–13% of benign laryngeal lesions and are typically classified as either epidermal inclusion or mucus retention cysts.1,2 Epidermal inclusion cysts are composed of caseous material encased in stratified squamous and keratinizing epithelium.3 They are thought to form as a result of phonotrauma leading to trapping of epithelium within the lamina propria.2 Mucus retention cysts are lined with ciliated epithelium4 and form as a result of obstructed glandular ducts. The obstruction of these ducts and subsequent cyst formation may result from phonotrauma, chronic laryngitis, or infection.2 Vocal fold cysts are typically unilateral and result in a significant reduction in the vibratory properties of the true vocal fold mucosa on videostroboscopy.5 Due to their mid-membranous location and tendency to distort the free edge of the vocal fold, an hourglass closure pattern is often noted on videostroboscopy as well. Vocal fold cysts may result in significant dysphonia due to their effect on vocal fold vibration and glottic closure. Figure 1 displays typical appearances of epidermal inclusion and mucus retention cysts. Surgical excision with the microflap technique is the mainstay of treatment of vocal fold cysts. These lesions typically do not Accepted for publication June 8, 2017. These data were presented as an oral presentation at the Fall Voice Conference in Pittsburgh, Pennsylvania, in October 2015. From the University of Texas Voice Center, University of Texas Health Science CenterSan Antonio, Department of Otolaryngology-Head and Neck Surgery, San Antonio, Texas. Address correspondence and reprint requests to Kathleen M. Tibbetts, University of Texas Southwestern Medical Center, Department of Otolaryngology-Head and Neck Surgery, 5323 Harry Hines Boulevard, Dallas, Texas 75390. E-mail: [email protected] Journal of Voice, Vol. ■■, No. ■■, pp. ■■-■■ 0892-1997 © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jvoice.2017.06.004
resolve with voice therapy, and observation of cysts could potentially risk rupture, which may result in scarring or sulcus formation. Surgical excision, however, also risks scarring of the vocal fold, leading to a poor vocal outcome.6 Additionally, some patients are either unwilling or unable to undergo surgery for these benign lesions. In this study, we review our outcomes in the surgical and nonsurgical treatment of vocal cysts in order to determine the most effective management strategy. We hypothesized that surgical excision is a safe and effective treatment for vocal fold cysts. In addition, we hypothesized that patients undergoing postoperative voice therapy would have better outcomes compared with surgery alone.
MATERIALS AND METHODS Patient cohort Under an Institutional Review Board-approved protocol, the medical records of adult patients treated at our institution for vocal fold cysts between 2009 and 2014 were reviewed. Patients were identified via a search of existing records for the International Classification of Diseases (ICD)-9 codes for benign laryngeal lesions (478.4-6). The records were then reviewed to identify patients who were diagnosed with vocal fold cysts. Patients included in the study had complete medical records, including Voice Handicap Index (VHI)-10 questionnaire scores and recorded videostroboscopy examinations before and after treatment. Patients with incomplete medical records were excluded from the analysis. Voice evaluations and therapy sessions for all study patients were performed by the same speech language pathologist. Surgical treatment was performed under general anesthesia and consisted of suspension laryngoscopy with microflap excision (MFE) of the cyst.
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vocal fold, scoring it as either normal, present but decreased, or absent. Statistical analysis VHI-10 scores before and after treatment were compared using the Wilcoxon rank-sum test. Changes in the VHI-10 between the different treatment modalities were compared using a two-tailed Student’s t test. Interrater reliability between the two clinicians who reviewed the videostroboscopy examinations was calculated to determine percent agreement and Krippendorff’s alpha.
A.
B.
FIGURE 1. A. Epidermal inclusion cyst involving the superior surface of the left true vocal fold. B. Mucus retention cyst involving the free edge of the left true vocal fold.
Data collected and outcomes measured Existing electronic medical records were reviewed, and data pertaining to patient demographics, treatment modalities, and VHI-10 scores before and after treatment were recorded. Operative and pathology reports were reviewed to determine cyst type (epidermal inclusion versus mucus retention). Videostroboscopy examinations before and after treatment were reviewed and scored by a blinded laryngologist and speech language pathologist. All videostroboscopy examinations were performed with either a 70° rigid endoscope (KayPENTAX, Montvale, New Jersey) or via a flexible laryngoscope with a distal chip (Olympus ENF-VQ, Olympus Surgical, Center Valley, Pennsylvania). Pretreatment and posttreatment examinations were performed with the same style of laryngoscope (either rigid or flexible for both examinations) for consistency. The reviewers rated the mucosal wave as either improved or not improved compared with the pretreatment examination. Additionally, the reviewers compared the mucosal wave of the involved vocal fold to that of the uninvolved
RESULTS Twenty-five patients who underwent treatment for a vocal fold cyst between 2009 and 2014 were identified, and one patient was excluded for incomplete medical records. Mean age at diagnosis was 41.9 years (range 22–69 years), and 16 patients were female (66.7%). Mean follow-up time after initial diagnosis was 5.58 months (range 0.17–54 months, median 3 months). Twenty-one patients (21/24, 87.5%) underwent MFE of their cyst, with 14/21 (66.7% of surgical patients, 58.3% overall) pursuing perioperative voice therapy. One patient (4.2%) opted for voice therapy alone, and two patients (8.3%) deferred any treatment but did follow up for repeat videostroboscopy to monitor the lesion. Patients who pursued voice therapy attended a mean of 4.25 (range 1–10) sessions. The type of cyst was documented in either the operative or pathology report, with 19/21 (90%) characterized as mucus retention cysts and 2/21 (10%) characterized as an epidermal inclusion cyst. Four surgical patients underwent either subepithelial steroid injection concurrently or noncontact potassium titanyl phosphate (KTP) laser treatment after MFE to reduce the risk of scar formation postoperatively. One patient’s vocal fold cyst recurred after initial MFE with no recurrence after re-excision (1/21, recurrence rate 4.8%). A comparison of VHI-10 scores before and after treatment is displayed in Table 1. Statistically significant improvements in VHI-10 scores were observed in patients who underwent MFE with or without perioperative voice therapy and in the patient cohort overall. The patients who opted for no treatment did not have a statistically significant improvement in VHI-10 at followup, although there was a mean improvement of 5.5 in their VHI-10 scores. As only one patient underwent voice therapy alone, statistical significance cannot be determined; however, the patient’s VHI-10 did improve 19 points (30–11) after a course
TABLE 1. Comparison of Mean VHI-10 Scores Before and After Treatment Overall and for Each Treatment Group. The Wilcoxon Rank-Sum Test was Applied to Determine If the Change in VHI-10 Within Each Group Was Statistically Significant
Pretreatment VHI-10 Posttreatment VHI-10 Change in VHI-10 P
All Patients (n = 24)
MFE (n = 7)
MFE + Voice Therapy (n = 14)
Voice Therapy (n = 1)
No Treatment (n = 2)
23.83 6.5 17.33 <0.001
28.29 8 20.29 0.004
20.42 3 17.43 <0.001
30 11 19 N/A
29 23.5 5.5 0.57
Abbreviations: MFE, microflap excision; VHI, Voice Handicap Index.
ARTICLE IN PRESS Kathleen M. Tibbetts, et al
Impact of Perioperative Voice Therapy on Vocal Fold Cysts
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TABLE 2. Scoring of Mucosal Wave After Treatment by Two Blinded Clinicians Mucosal Wave Improved/ Not Improved
Mucosal Wave Compared with Uninvolved Vocal Fold
Rater 1
Improved: 91% Not Improved: 9%
Rater 2
Improved: 100% Not Improved: 0
Percent Agreement Krippendorff’s α
90.0% −0.024
Normal: 59% Present but Decreased: 36.3% Absent: 4.5% Normal: 72.3% Present but Decreased: 27.3% Absent: 0 72.7% 0.425
of voice therapy. The mean VHI-10 results in those patients who had postoperative voice therapy was improved compared with surgery alone (three versus eight); however, there was no significant difference in the change in VHI-10 scores between patients who underwent MFE alone or MFE followed by voice therapy (P = 0.65). Videostroboscopy examinations before and after treatment were reviewed and scored by a blinded laryngologist and speech language pathologist. The examinations of the patients who opted for no treatment of their cyst were not reviewed. When comparing the posttreatment videostroboscopy examinations with the pretreatment studies, the reviewers scored 91% and 100% of patients as having an improvement in the mucosal wave of the involved vocal fold after treatment (90.0% agreement, Krippendorff’s α = −0.024). The reviewers also compared the mucosal wave of the involved vocal fold with the uninvolved vocal fold on the posttreatment examination. One reviewer scored the involved vocal fold mucosal wave as normal in 59%, present but decreased in 36.3%, and absent in 4.5%. The other reviewer scored 72.3% as having a normal mucosal wave, 27.3% as present but decreased wave, and none as absent wave (72.7% agreement, Krippendorff’s α = 0.425). Their ratings are summarized in Table 2. In the one patient who underwent voice therapy alone, both raters scored the posttreatment mucosal wave as improved. DISCUSSION Vocal fold cysts may result in significant dysphonia due to disruption of the mucosal wave of the vocal fold and prevention of complete glottic closure during phonation. Our data suggest that surgical outcomes in patients undergoing MFE of a vocal fold cyst are favorable with respect to both subjective VHI-10 scores and preservation of pliability/mucosal wave of the vocal fold. Patients who underwent MFE with or without perioperative voice therapy in our study population had a statistically significant reduction in their VHI-10 scores posttreatment. The mean aggregate VHI-10 score for all study participants and the surgical treatment groups (with and without additional voice therapy) decreased to the normal range (VHI-10 < 11)7 posttreatment. These findings build on previous studies of patients undergoing surgical management of vocal fold cysts, which have also shown favorable outcomes. Johns et al reported a statistically significant reduction in VHI-10 scores in 13 patients undergoing endoscopic laryngeal surgery for vocal fold cysts, with all
postoperative VHI-10 scores being within the normal range.8 Akbulut et al studied outcomes after treatment of patients with benign mid-membranous vocal fold lesions, including patients with ligamentous and subepithelial vocal fold cysts. All surgical patients demonstrated statistically significant reductions in VHI-10 scores after treatment, with patients with subepithelial cysts showing the largest mean change in VHI-10 (16.42).9 The findings of our study further support MFE as an effective primary treatment modality for vocal fold cysts. Standard treatment protocols following MFE of benign vocal fold lesions generally include postoperative voice therapy.9 No previous studies, however, have directly compared outcomes in patients treated with and without voice therapy after surgical management of vocal fold cysts. Our data suggest no difference in outcomes between patients who underwent MFE of their vocal fold cyst with and without perioperative or postoperative voice therapy. One possible explanation for this finding is that removal of the cyst with restoration of the mucosal wave and glottic closure is adequate to improve many patients’ subjective and objective voice quality, and voice therapy does not offer additional benefit. It is more likely, however, that some selection bias exists: patients who were satisfied with their voice quality after surgery alone did not pursue voice therapy, while patients who did not feel their voice completely normalized postoperatively pursued voice therapy with eventual improvement. It is also possible that the lack of a statistically significant difference between patients who did and did not pursue voice therapy could be related to the prevalence of mucus retention cysts in our cohort. While these lesions have been attributed to phonotrauma, they are also thought to result from acute infection or chronic laryngitis. Thus, mucus retention cysts may not result from vocally abusive behaviors. In this case, one would not expect voice therapy to impact surgical outcomes as there would be no causative vocal behaviors to address with therapy. Epidermal inclusion cysts, however, are more often considered to be phonotraumatic lesions resulting from prolonged vocal abuse. If these lesions were more prevalent in our population, it is possible that voice therapy would have had a more significant effect on our patients’ outcomes. In some patients undergoing MFE for management of their vocal fold cyst, a subepithelial steroid injection or noncontact KTP laser treatment was employed at the time of surgery to prevent scar formation. Steroid injection is widely accepted in the dermatology literature as a treatment for hypertrophic scars
ARTICLE IN PRESS 4 and keloids.10 Its efficacy is attributed to anti-inflammatory properties and reduction in multiple aspects of scar formation, including synthesis of collagen and glycosaminoglycans as well as fibroblast proliferation.11,12 Steroid injection for the prevention of vocal fold scar has been described as well. Bouchayer and Cornut described injection of hydrocortisone in the vocal folds after excision of benign laryngeal lesions, including vocal fold cysts, to prevent scar formation. The authors reported improvement in vocal fold suppleness, glottic closure, and voice quality with this technique.1,13 Improvement in existing vocal fold scar has been demonstrated as well, with Mortensen and Woo obtaining statistically significant improvements in voice grade, mucosal wave, and amplitude in patients undergoing steroid injection for vocal fold scar.14 Pulsed dye laser (PDL) treatment for the prevention and modulation of scars is also described in the dermatology literature. Like the KTP laser, the 585 and 595 nanometer PDL lasers target oxyhemoglobin. This is thought to impair the local microcirculation, thus reducing the proliferation of fibroblasts and preventing hypertrophic scar formation.15 PDL has also been shown to reduce collagen deposition and expression of TGF-βI.16 Pulsed KTP laser treatment has also been applied to benign vocal fold lesions, including vocal fold scar.17 Given that these adjunctive treatments were not applied to all patients undergoing surgical management of their vocal fold cysts, we are unable to draw conclusions as to whether or not this may have impacted patient outcomes. Nonsurgical treatment of vocal fold cysts and other benign vocal fold lesions has also been studied with favorable results reported in some patients. Cohen and Garrett18 found that in 57 patients with vocal fold cysts and polyps treated with voice therapy alone, 49.1% overall had an improvement in their voice quality. In patients with vocal fold cysts, 60% had improvement in voice with therapy alone, and one patient’s cyst completely resolved on follow-up examination. The authors suggest that improving vocal efficiency may improve voice quality in these patients even without resolution of the lesion. With respect to vocal fold cysts, while it is unlikely that these lesions will resolve with voice therapy alone, there is the potential for improvement in the mucosal wave and, thus, voice quality due to improvements in vocal efficiency. Only one patient in our cohort opted to pursue voice therapy alone and had a subjective improvement in voice quality as evidenced by a reduction in the VHI-10 score after treatment. Additionally, the patient’s mucosal wave on videostroboscopy was felt to be improved after treatment by both raters despite persistence of the lesion. While we cannot draw conclusions on the merits of voice therapy alone based on the one patient in our cohort, this does strengthen the findings of the abovementioned study that voice therapy alone may offer some benefit. For patients who are poor surgical candidates or do not wish to undergo surgery, voice therapy offers the potential for improvement in vocal quality. Patients should be counseled, however, that the lesion is not expected to resolve with therapy alone. It is notable that the ratio of mucus retention cysts to epidermal inclusion cysts in our patient population is dissimilar to previous reports in the literature. In the 21 patients whose cyst type was documented, there was a roughly 10:1 ratio of mucus retention cysts to epidermal inclusion cysts. This differs from
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previous reports in the literature citing a much higher proportion of epidermal inclusion cysts. In a study from Brazil, Martins et al reported that out of 46 patients undergoing phonosurgery for vocal fold cysts, 27 (59%) were found to have epidermal inclusion cysts versus 19 (41%) mucus retention cysts intraoperatively.2 A substantial number of these patients had associated lesions including mucosal bridge and sulcus defects, which are more commonly linked to epidermal inclusion cysts. As observed by Husain and Sulica, certain population groups (Brazil in particular) seem to have a higher prevalence of sulcus vergeture, thought to be a congenital abnormality, and thus this could be a reason for the observed differences.19 Others have also theorized that epidermal inclusion cysts, as well as mucosal bridge and sulcus, may be congenital lesions. Monday et al described 53 patients with epidermal inclusion cysts and hypothesized that these lesions may be traumatic or congenital. In addition to a high prevalence of vocal abuse in their patient population, they also noted mucosal bridges and/or sulci in 21 patients. Twelve of these patients reported a prolonged or lifelong history of dysphonia.3 These findings strengthen the assertion that a portion of epidermal inclusion cysts are congenital or secondarily related to other congenital lesions, which are apparently not as prevalent in our population. The study by Martins et al included children, as well as 11 adult patients with dysphonia since childhood. One would expect a higher prevalence of congenital and congenitalrelated lesions in this population, as opposed to our cohort of adult patients with a more recent onset of dysphonia. It is possible that our patient population has a lower prevalence of congenital vocal fold lesions or that these patients were not captured in our population due to the demographics of patients evaluated in our practice (primarily adults). This study is limited primarily by its small sample size and retrospective nature. The small sample size limits our ability to draw definite conclusions regarding treatment outcomes, especially with respect to voice therapy alone as a treatment for vocal fold cysts, as only one patient in our population exclusively pursued voice therapy. A larger multi-institutional study would increase statistical power and strengthen the conclusions we are able to draw regarding treatment outcomes in patients with vocal fold cysts. Given the retrospective nature of the study, we were unable to completely standardize the treatment regimens and lack complete data for some variables, such as classification of all cysts as either epidermal inclusion or mucus retention. A prospective study with standardized treatment stratifications would reduce this limitation, but given the relatively sporadic nature of these lesions, a multi-institutional effort may be necessary to accrue an adequate number of patients. This study benefits from an extended follow-up time as well as consistent subjective (VHI-10) and objective (videostroboscopy examinations) pretreatment and posttreatment data for study subjects. Despite the small sample size, the findings of this study further support MFE as an effective first-line treatment for vocal fold cysts. CONCLUSION Vocal fold cysts are benign lesions that often greatly impact vocal fold vibration and glottic closure. In our study, the vast majority (90%) of vocal fold cysts were mucous retention while only
ARTICLE IN PRESS Kathleen M. Tibbetts, et al
Impact of Perioperative Voice Therapy on Vocal Fold Cysts
10% were epidermal inclusion, in contrast to other published studies. Surgical excision is a successful treatment with low rates of recurrence and results in improvement in mucosal wave and subjective voice scores in the majority of patients. Although there may be some benefit from postoperative voice therapy, we could not demonstrate a significant difference over surgery alone. Acknowledgment The authors would like to thank Joel E. Michalek, PhD, for his assistance with the statistical analysis. REFERENCES 1. Bouchayer M, Cornut G. Microsurgery for benign lesions of the vocal folds. Ear Nose Throat J. 1988;67:446–466. 2. Martins RH, Santana MF, Tavares EL. Vocal cysts: clinical, endoscopic, and surgical aspects. J Voice. 2011;25:107–110. 3. Monday LA, Bouchayer M, Cornut G, et al. Epidermoid cysts of vocal cords. Ann Otol Rhinol Laryngol. 1983;92:124–127. 4. Johns MM. Update on the etiology, diagnosis, and treatment of vocal fold nodules, polyps and cysts. Curr Opin Otolaryngol Head Neck Surg. 2003;11:456–461. 5. Rosen CA, Gartner-Schmidt J, Hathaway B, et al. A nomenclature paradigm for benign midmembranous vocal fold lesions. Laryngoscope. 2012;122: 1335–1341. 6. Courey MS, Garrett CG, Ossoff RH. Medial microflap for excision of benign vocal fold lesions. Laryngoscope. 1997;107:340–344. 7. Arffa RE, Krishna P, Gartner-Schmidt J, et al. Normative values for the Voice Handicap Index-10. J Voice. 2012;26:462–465.
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8. Johns MM, Garrett CG, Hwang J, et al. Quality-of-life outcomes following laryngeal endoscopic surgery for non-neoplastic vocal fold lesions. Ann Otol Rhinol Laryngol. 2004;113:597–601. 9. Akbulut S, Gartner-Schmidt JL, Gillespie AI, et al. Voice outcomes following treatment of benign midmembranous vocal fold lesions using a nomenclature paradigm. Laryngoscope. 2016;126:415–420. 10. Ketchum LD, Smith J, Robinson DW, et al. The treatment of hypertrophic scar, keloid and scar contracture by triamcinolone acetonide. Plast Reconstr Surg. 1966;38:209–218. 11. McCoy BJ, Diegelmann RF, Cohen IK. In vitro inhibition of cell growth, collagen synthesis, and prolyl hydroxylase activity by triamcinolone acetonide. Exp Biol Med. 1980;163:216–222. 12. Alaish SM, Yager DR, Diegelmann RF, et al. Hyaluronic acid metabolism in keloid fibroblasts. J Pediatr Surg. 1995;30:949–952. 13. Bouchayer M, Cornut G. Microsurgical treatment of benign vocal fold lesions: indications, technique, results. Folia Phoniatr (Basel). 1992;44:155– 184. 14. Mortensen M, Woo P. Office steroid injections of the larynx. Laryngoscope. 2006;116:1735–1739. 15. Liu A, Moy RL, Ozog DM. Current methods employed in the prevention and minimization of surgical scars. Dermatol Surg. 2011;37:1740–1746. 16. Kuo YR, Jeng SF, Wang FS, et al. Flashlamp pulsed dye laser (PDL) suppression of keloid proliferation through down-regulation of TGF-beta I expression and extracellular matrix expression. Lasers Surg Med. 2004;34:104–108. 17. Sheu M, Sridharan S, Kuhn M, et al. Multi-institutional experience with the in-office potassium titanyl phosphate laser for laryngeal lesions. J Voice. 2012;26:806–810. 18. Cohen SM, Garrett CG. Utility of voice therapy in the management of vocal fold polyps and cysts. Otolaryngol Head Neck Surg. 2007;136:742–746. 19. Husain S, Sulica L. Familial sulcus vergeture: further evidence for congenital origin of type 2 sulcus. J Voice. 2016;30:761.
resolve with voice therapy, and observation of cysts could potentially risk rupture, which may result in scarring or sulcus formation. Surgical excision, however, also risks scarring of the vocal fold, leading to a poor vocal outcome.6 Additionally, some patients are either unwilling or unable to undergo surgery for these benign lesions. In this study, we review our outcomes in the surgical and nonsurgical treatment of vocal cysts in order to determine the most effective management strategy. We hypothesized that surgical excision is a safe and effective treatment for vocal fold cysts. In addition, we hypothesized that patients undergoing postoperative voice therapy would have better outcomes compared with surgery alone.
MATERIALS AND METHODS Patient cohort Under an Institutional Review Board-approved protocol, the medical records of adult patients treated at our institution for vocal fold cysts between 2009 and 2014 were reviewed. Patients were identified via a search of existing records for the International Classification of Diseases (ICD)-9 codes for benign laryngeal lesions (478.4-6). The records were then reviewed to identify patients who were diagnosed with vocal fold cysts. Patients included in the study had complete medical records, including Voice Handicap Index (VHI)-10 questionnaire scores and recorded videostroboscopy examinations before and after treatment. Patients with incomplete medical records were excluded from the analysis. Voice evaluations and therapy sessions for all study patients were performed by the same speech language pathologist. Surgical treatment was performed under general anesthesia and consisted of suspension laryngoscopy with microflap excision (MFE) of the cyst.
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vocal fold, scoring it as either normal, present but decreased, or absent. Statistical analysis VHI-10 scores before and after treatment were compared using the Wilcoxon rank-sum test. Changes in the VHI-10 between the different treatment modalities were compared using a two-tailed Student’s t test. Interrater reliability between the two clinicians who reviewed the videostroboscopy examinations was calculated to determine percent agreement and Krippendorff’s alpha.
A.
B.
FIGURE 1. A. Epidermal inclusion cyst involving the superior surface of the left true vocal fold. B. Mucus retention cyst involving the free edge of the left true vocal fold.
Data collected and outcomes measured Existing electronic medical records were reviewed, and data pertaining to patient demographics, treatment modalities, and VHI-10 scores before and after treatment were recorded. Operative and pathology reports were reviewed to determine cyst type (epidermal inclusion versus mucus retention). Videostroboscopy examinations before and after treatment were reviewed and scored by a blinded laryngologist and speech language pathologist. All videostroboscopy examinations were performed with either a 70° rigid endoscope (KayPENTAX, Montvale, New Jersey) or via a flexible laryngoscope with a distal chip (Olympus ENF-VQ, Olympus Surgical, Center Valley, Pennsylvania). Pretreatment and posttreatment examinations were performed with the same style of laryngoscope (either rigid or flexible for both examinations) for consistency. The reviewers rated the mucosal wave as either improved or not improved compared with the pretreatment examination. Additionally, the reviewers compared the mucosal wave of the involved vocal fold to that of the uninvolved
RESULTS Twenty-five patients who underwent treatment for a vocal fold cyst between 2009 and 2014 were identified, and one patient was excluded for incomplete medical records. Mean age at diagnosis was 41.9 years (range 22–69 years), and 16 patients were female (66.7%). Mean follow-up time after initial diagnosis was 5.58 months (range 0.17–54 months, median 3 months). Twenty-one patients (21/24, 87.5%) underwent MFE of their cyst, with 14/21 (66.7% of surgical patients, 58.3% overall) pursuing perioperative voice therapy. One patient (4.2%) opted for voice therapy alone, and two patients (8.3%) deferred any treatment but did follow up for repeat videostroboscopy to monitor the lesion. Patients who pursued voice therapy attended a mean of 4.25 (range 1–10) sessions. The type of cyst was documented in either the operative or pathology report, with 19/21 (90%) characterized as mucus retention cysts and 2/21 (10%) characterized as an epidermal inclusion cyst. Four surgical patients underwent either subepithelial steroid injection concurrently or noncontact potassium titanyl phosphate (KTP) laser treatment after MFE to reduce the risk of scar formation postoperatively. One patient’s vocal fold cyst recurred after initial MFE with no recurrence after re-excision (1/21, recurrence rate 4.8%). A comparison of VHI-10 scores before and after treatment is displayed in Table 1. Statistically significant improvements in VHI-10 scores were observed in patients who underwent MFE with or without perioperative voice therapy and in the patient cohort overall. The patients who opted for no treatment did not have a statistically significant improvement in VHI-10 at followup, although there was a mean improvement of 5.5 in their VHI-10 scores. As only one patient underwent voice therapy alone, statistical significance cannot be determined; however, the patient’s VHI-10 did improve 19 points (30–11) after a course
TABLE 1. Comparison of Mean VHI-10 Scores Before and After Treatment Overall and for Each Treatment Group. The Wilcoxon Rank-Sum Test was Applied to Determine If the Change in VHI-10 Within Each Group Was Statistically Significant
Pretreatment VHI-10 Posttreatment VHI-10 Change in VHI-10 P
All Patients (n = 24)
MFE (n = 7)
MFE + Voice Therapy (n = 14)
Voice Therapy (n = 1)
No Treatment (n = 2)
23.83 6.5 17.33 <0.001
28.29 8 20.29 0.004
20.42 3 17.43 <0.001
30 11 19 N/A
29 23.5 5.5 0.57
Abbreviations: MFE, microflap excision; VHI, Voice Handicap Index.
ARTICLE IN PRESS Kathleen M. Tibbetts, et al
Impact of Perioperative Voice Therapy on Vocal Fold Cysts
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TABLE 2. Scoring of Mucosal Wave After Treatment by Two Blinded Clinicians Mucosal Wave Improved/ Not Improved
Mucosal Wave Compared with Uninvolved Vocal Fold
Rater 1
Improved: 91% Not Improved: 9%
Rater 2
Improved: 100% Not Improved: 0
Percent Agreement Krippendorff’s α
90.0% −0.024
Normal: 59% Present but Decreased: 36.3% Absent: 4.5% Normal: 72.3% Present but Decreased: 27.3% Absent: 0 72.7% 0.425
of voice therapy. The mean VHI-10 results in those patients who had postoperative voice therapy was improved compared with surgery alone (three versus eight); however, there was no significant difference in the change in VHI-10 scores between patients who underwent MFE alone or MFE followed by voice therapy (P = 0.65). Videostroboscopy examinations before and after treatment were reviewed and scored by a blinded laryngologist and speech language pathologist. The examinations of the patients who opted for no treatment of their cyst were not reviewed. When comparing the posttreatment videostroboscopy examinations with the pretreatment studies, the reviewers scored 91% and 100% of patients as having an improvement in the mucosal wave of the involved vocal fold after treatment (90.0% agreement, Krippendorff’s α = −0.024). The reviewers also compared the mucosal wave of the involved vocal fold with the uninvolved vocal fold on the posttreatment examination. One reviewer scored the involved vocal fold mucosal wave as normal in 59%, present but decreased in 36.3%, and absent in 4.5%. The other reviewer scored 72.3% as having a normal mucosal wave, 27.3% as present but decreased wave, and none as absent wave (72.7% agreement, Krippendorff’s α = 0.425). Their ratings are summarized in Table 2. In the one patient who underwent voice therapy alone, both raters scored the posttreatment mucosal wave as improved. DISCUSSION Vocal fold cysts may result in significant dysphonia due to disruption of the mucosal wave of the vocal fold and prevention of complete glottic closure during phonation. Our data suggest that surgical outcomes in patients undergoing MFE of a vocal fold cyst are favorable with respect to both subjective VHI-10 scores and preservation of pliability/mucosal wave of the vocal fold. Patients who underwent MFE with or without perioperative voice therapy in our study population had a statistically significant reduction in their VHI-10 scores posttreatment. The mean aggregate VHI-10 score for all study participants and the surgical treatment groups (with and without additional voice therapy) decreased to the normal range (VHI-10 < 11)7 posttreatment. These findings build on previous studies of patients undergoing surgical management of vocal fold cysts, which have also shown favorable outcomes. Johns et al reported a statistically significant reduction in VHI-10 scores in 13 patients undergoing endoscopic laryngeal surgery for vocal fold cysts, with all
postoperative VHI-10 scores being within the normal range.8 Akbulut et al studied outcomes after treatment of patients with benign mid-membranous vocal fold lesions, including patients with ligamentous and subepithelial vocal fold cysts. All surgical patients demonstrated statistically significant reductions in VHI-10 scores after treatment, with patients with subepithelial cysts showing the largest mean change in VHI-10 (16.42).9 The findings of our study further support MFE as an effective primary treatment modality for vocal fold cysts. Standard treatment protocols following MFE of benign vocal fold lesions generally include postoperative voice therapy.9 No previous studies, however, have directly compared outcomes in patients treated with and without voice therapy after surgical management of vocal fold cysts. Our data suggest no difference in outcomes between patients who underwent MFE of their vocal fold cyst with and without perioperative or postoperative voice therapy. One possible explanation for this finding is that removal of the cyst with restoration of the mucosal wave and glottic closure is adequate to improve many patients’ subjective and objective voice quality, and voice therapy does not offer additional benefit. It is more likely, however, that some selection bias exists: patients who were satisfied with their voice quality after surgery alone did not pursue voice therapy, while patients who did not feel their voice completely normalized postoperatively pursued voice therapy with eventual improvement. It is also possible that the lack of a statistically significant difference between patients who did and did not pursue voice therapy could be related to the prevalence of mucus retention cysts in our cohort. While these lesions have been attributed to phonotrauma, they are also thought to result from acute infection or chronic laryngitis. Thus, mucus retention cysts may not result from vocally abusive behaviors. In this case, one would not expect voice therapy to impact surgical outcomes as there would be no causative vocal behaviors to address with therapy. Epidermal inclusion cysts, however, are more often considered to be phonotraumatic lesions resulting from prolonged vocal abuse. If these lesions were more prevalent in our population, it is possible that voice therapy would have had a more significant effect on our patients’ outcomes. In some patients undergoing MFE for management of their vocal fold cyst, a subepithelial steroid injection or noncontact KTP laser treatment was employed at the time of surgery to prevent scar formation. Steroid injection is widely accepted in the dermatology literature as a treatment for hypertrophic scars
ARTICLE IN PRESS 4 and keloids.10 Its efficacy is attributed to anti-inflammatory properties and reduction in multiple aspects of scar formation, including synthesis of collagen and glycosaminoglycans as well as fibroblast proliferation.11,12 Steroid injection for the prevention of vocal fold scar has been described as well. Bouchayer and Cornut described injection of hydrocortisone in the vocal folds after excision of benign laryngeal lesions, including vocal fold cysts, to prevent scar formation. The authors reported improvement in vocal fold suppleness, glottic closure, and voice quality with this technique.1,13 Improvement in existing vocal fold scar has been demonstrated as well, with Mortensen and Woo obtaining statistically significant improvements in voice grade, mucosal wave, and amplitude in patients undergoing steroid injection for vocal fold scar.14 Pulsed dye laser (PDL) treatment for the prevention and modulation of scars is also described in the dermatology literature. Like the KTP laser, the 585 and 595 nanometer PDL lasers target oxyhemoglobin. This is thought to impair the local microcirculation, thus reducing the proliferation of fibroblasts and preventing hypertrophic scar formation.15 PDL has also been shown to reduce collagen deposition and expression of TGF-βI.16 Pulsed KTP laser treatment has also been applied to benign vocal fold lesions, including vocal fold scar.17 Given that these adjunctive treatments were not applied to all patients undergoing surgical management of their vocal fold cysts, we are unable to draw conclusions as to whether or not this may have impacted patient outcomes. Nonsurgical treatment of vocal fold cysts and other benign vocal fold lesions has also been studied with favorable results reported in some patients. Cohen and Garrett18 found that in 57 patients with vocal fold cysts and polyps treated with voice therapy alone, 49.1% overall had an improvement in their voice quality. In patients with vocal fold cysts, 60% had improvement in voice with therapy alone, and one patient’s cyst completely resolved on follow-up examination. The authors suggest that improving vocal efficiency may improve voice quality in these patients even without resolution of the lesion. With respect to vocal fold cysts, while it is unlikely that these lesions will resolve with voice therapy alone, there is the potential for improvement in the mucosal wave and, thus, voice quality due to improvements in vocal efficiency. Only one patient in our cohort opted to pursue voice therapy alone and had a subjective improvement in voice quality as evidenced by a reduction in the VHI-10 score after treatment. Additionally, the patient’s mucosal wave on videostroboscopy was felt to be improved after treatment by both raters despite persistence of the lesion. While we cannot draw conclusions on the merits of voice therapy alone based on the one patient in our cohort, this does strengthen the findings of the abovementioned study that voice therapy alone may offer some benefit. For patients who are poor surgical candidates or do not wish to undergo surgery, voice therapy offers the potential for improvement in vocal quality. Patients should be counseled, however, that the lesion is not expected to resolve with therapy alone. It is notable that the ratio of mucus retention cysts to epidermal inclusion cysts in our patient population is dissimilar to previous reports in the literature. In the 21 patients whose cyst type was documented, there was a roughly 10:1 ratio of mucus retention cysts to epidermal inclusion cysts. This differs from
Journal of Voice, Vol. ■■, No. ■■, 2017
previous reports in the literature citing a much higher proportion of epidermal inclusion cysts. In a study from Brazil, Martins et al reported that out of 46 patients undergoing phonosurgery for vocal fold cysts, 27 (59%) were found to have epidermal inclusion cysts versus 19 (41%) mucus retention cysts intraoperatively.2 A substantial number of these patients had associated lesions including mucosal bridge and sulcus defects, which are more commonly linked to epidermal inclusion cysts. As observed by Husain and Sulica, certain population groups (Brazil in particular) seem to have a higher prevalence of sulcus vergeture, thought to be a congenital abnormality, and thus this could be a reason for the observed differences.19 Others have also theorized that epidermal inclusion cysts, as well as mucosal bridge and sulcus, may be congenital lesions. Monday et al described 53 patients with epidermal inclusion cysts and hypothesized that these lesions may be traumatic or congenital. In addition to a high prevalence of vocal abuse in their patient population, they also noted mucosal bridges and/or sulci in 21 patients. Twelve of these patients reported a prolonged or lifelong history of dysphonia.3 These findings strengthen the assertion that a portion of epidermal inclusion cysts are congenital or secondarily related to other congenital lesions, which are apparently not as prevalent in our population. The study by Martins et al included children, as well as 11 adult patients with dysphonia since childhood. One would expect a higher prevalence of congenital and congenitalrelated lesions in this population, as opposed to our cohort of adult patients with a more recent onset of dysphonia. It is possible that our patient population has a lower prevalence of congenital vocal fold lesions or that these patients were not captured in our population due to the demographics of patients evaluated in our practice (primarily adults). This study is limited primarily by its small sample size and retrospective nature. The small sample size limits our ability to draw definite conclusions regarding treatment outcomes, especially with respect to voice therapy alone as a treatment for vocal fold cysts, as only one patient in our population exclusively pursued voice therapy. A larger multi-institutional study would increase statistical power and strengthen the conclusions we are able to draw regarding treatment outcomes in patients with vocal fold cysts. Given the retrospective nature of the study, we were unable to completely standardize the treatment regimens and lack complete data for some variables, such as classification of all cysts as either epidermal inclusion or mucus retention. A prospective study with standardized treatment stratifications would reduce this limitation, but given the relatively sporadic nature of these lesions, a multi-institutional effort may be necessary to accrue an adequate number of patients. This study benefits from an extended follow-up time as well as consistent subjective (VHI-10) and objective (videostroboscopy examinations) pretreatment and posttreatment data for study subjects. Despite the small sample size, the findings of this study further support MFE as an effective first-line treatment for vocal fold cysts. CONCLUSION Vocal fold cysts are benign lesions that often greatly impact vocal fold vibration and glottic closure. In our study, the vast majority (90%) of vocal fold cysts were mucous retention while only
ARTICLE IN PRESS Kathleen M. Tibbetts, et al
Impact of Perioperative Voice Therapy on Vocal Fold Cysts
10% were epidermal inclusion, in contrast to other published studies. Surgical excision is a successful treatment with low rates of recurrence and results in improvement in mucosal wave and subjective voice scores in the majority of patients. Although there may be some benefit from postoperative voice therapy, we could not demonstrate a significant difference over surgery alone. Acknowledgment The authors would like to thank Joel E. Michalek, PhD, for his assistance with the statistical analysis. REFERENCES 1. Bouchayer M, Cornut G. Microsurgery for benign lesions of the vocal folds. Ear Nose Throat J. 1988;67:446–466. 2. Martins RH, Santana MF, Tavares EL. Vocal cysts: clinical, endoscopic, and surgical aspects. J Voice. 2011;25:107–110. 3. Monday LA, Bouchayer M, Cornut G, et al. Epidermoid cysts of vocal cords. Ann Otol Rhinol Laryngol. 1983;92:124–127. 4. Johns MM. Update on the etiology, diagnosis, and treatment of vocal fold nodules, polyps and cysts. Curr Opin Otolaryngol Head Neck Surg. 2003;11:456–461. 5. Rosen CA, Gartner-Schmidt J, Hathaway B, et al. A nomenclature paradigm for benign midmembranous vocal fold lesions. Laryngoscope. 2012;122: 1335–1341. 6. Courey MS, Garrett CG, Ossoff RH. Medial microflap for excision of benign vocal fold lesions. Laryngoscope. 1997;107:340–344. 7. Arffa RE, Krishna P, Gartner-Schmidt J, et al. Normative values for the Voice Handicap Index-10. J Voice. 2012;26:462–465.
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8. Johns MM, Garrett CG, Hwang J, et al. Quality-of-life outcomes following laryngeal endoscopic surgery for non-neoplastic vocal fold lesions. Ann Otol Rhinol Laryngol. 2004;113:597–601. 9. Akbulut S, Gartner-Schmidt JL, Gillespie AI, et al. Voice outcomes following treatment of benign midmembranous vocal fold lesions using a nomenclature paradigm. Laryngoscope. 2016;126:415–420. 10. Ketchum LD, Smith J, Robinson DW, et al. The treatment of hypertrophic scar, keloid and scar contracture by triamcinolone acetonide. Plast Reconstr Surg. 1966;38:209–218. 11. McCoy BJ, Diegelmann RF, Cohen IK. In vitro inhibition of cell growth, collagen synthesis, and prolyl hydroxylase activity by triamcinolone acetonide. Exp Biol Med. 1980;163:216–222. 12. Alaish SM, Yager DR, Diegelmann RF, et al. Hyaluronic acid metabolism in keloid fibroblasts. J Pediatr Surg. 1995;30:949–952. 13. Bouchayer M, Cornut G. Microsurgical treatment of benign vocal fold lesions: indications, technique, results. Folia Phoniatr (Basel). 1992;44:155– 184. 14. Mortensen M, Woo P. Office steroid injections of the larynx. Laryngoscope. 2006;116:1735–1739. 15. Liu A, Moy RL, Ozog DM. Current methods employed in the prevention and minimization of surgical scars. Dermatol Surg. 2011;37:1740–1746. 16. Kuo YR, Jeng SF, Wang FS, et al. Flashlamp pulsed dye laser (PDL) suppression of keloid proliferation through down-regulation of TGF-beta I expression and extracellular matrix expression. Lasers Surg Med. 2004;34:104–108. 17. Sheu M, Sridharan S, Kuhn M, et al. Multi-institutional experience with the in-office potassium titanyl phosphate laser for laryngeal lesions. J Voice. 2012;26:806–810. 18. Cohen SM, Garrett CG. Utility of voice therapy in the management of vocal fold polyps and cysts. Otolaryngol Head Neck Surg. 2007;136:742–746. 19. Husain S, Sulica L. Familial sulcus vergeture: further evidence for congenital origin of type 2 sulcus. J Voice. 2016;30:761.