Voice Outcomes Following Treatment of Benign Midmembranous Vocal Fold Lesions Using a Nomenclature Paradigm

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1 The Laryngoscope VC 2015 The American Laryngological, Rhinological and Otological Society, Inc. Voice Outcomes Following Treatment of Benign Midmembranous Vocal Fold Lesions Using a Nomenclature Paradigm Sevtap Akbulut, MD; Jackie L. Gartner-Schmidt, PhD; Amanda I. Gillespie, PhD; VyVy N. Young, MD; Libby J. Smith, DO; Clark A. Rosen, MD Objectives/Hypothesis: Benign midmembranous vocal fold lesions (BMVFLs) are common voice disorders, but interpretation of outcomes following treatment is difficult due to the lack of a standardized nomenclature system for these lesions. Outcome results are increasingly important to third party payers. This study aimed to investigate the outcomes of patients with BMVFLs using a previously validated nomenclature, and to provide incidences and outcome results for each diagnosis. Methods: A retrospective chart review of BMVFL patients was performed. Treatment was individualized but typically involved implementation of nonsurgical therapy followed by phonomicrosurgery as needed. A previously reported BMVFL stratification system was used. Results: A total of 224 patients with BMVFLs were studied. Sixty-seven percent of all patients with a BMVFL underwent phonomicrosurgery. The most common BMVFL types were polyp and nonspecific vocal fold lesion. Pseudocyst represented 0.9% of the cohort. The Voice Handicap Index-10 (VHI-10) and acoustic data demonstrate a high degree of treatment success. The mean change in VHI-10 was greatest for cyst subepithelial and polyp. Fibrous mass ligamentous patients had the smallest mean change in VHI-10. Mean post-treatment VHI-10 scores of all the lesions except fibrous mass ligamentous were within normal limits (<11). Conclusions: This study represents the first outcomes-based report of BMVFLs using a strictly defined nomenclature system for stratification of lesions. Ligamentous fibrous mass lesions have a decreased response to treatment compared to all other lesions. This study demonstrates the ability to return most BMVFL patients to normal speaking voice capabilities following treatment. Key Words: Vocal cord lesions, vocal nodules, speech therapy, vocal cord polyp, nomenclature. Level of Evidence: 4. Laryngoscope, 126: , 2016 INTRODUCTION Benign midmembranous vocal fold lesions (BMVFLs) are a common cause of dysphonia. 1,2 A long history of undefined, or poorly defined, terms regarding BVMFL has hampered critical evaluation of lesion incidence and assessment of treatment outcomes. Rosen et al. proposed and validated a classification nomenclature system for adult patients with BMVFLs. 3 This approach involved common aspects of modern-day voice care. The classification system includes stroboscopic findings, lesion morphology, lesion size change following voice therapy, and when applicable, surgical findings to assign the BMVFL to one of nine lesion categories: vocal From the Department of Otolaryngology, Lutfi Kirdar Research Hospital, Istanbul, Turkey (S.A.) and University of Pittsburgh Voice Center, Department of Otolaryngology, University of Pittsburgh School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, U.S.A. (J.L.G.-S., A.I.G., V.N.Y., L.J.S., C.A.R.). Editor s Note: This Manuscript was accepted for publication May 22, Presented at the 136th Meeting of the American Laryngological Association, Boston, Massachusetts, U.S.A., April 22 23, The authors have no funding, financial relationships, or conflicts of interest to disclose. Send correspondence to Clark A. Rosen MD, University of Pittsburgh Voice Center, 1400 Locust Street, Bldg. B, #11500, Pittsburgh PA Rosenca@upmc.edu DOI: /lary fold nodules (nodules), vocal fold polyp (polyp), fibrous mass subepithelial (FM-SE), fibrous mass ligamentous (FM-lig), vocal fold cyst subepithelial (cyst-se), vocal fold cyst ligamentous (cyst-lig), pseudocyst, nonspecific vocal fold lesion (NSVFL), and reactive lesion (Table I). The current study aimed to investigate the outcomes of patients with BMVFLs using our previously validated nomenclature, and to provide incidences and outcome results for each diagnosis. MATERIALS AND METHODS All study procedures were approved by the University of Pittsburgh Institutional Review Board (PRO ). Informed consent was obtained from patients prior to entry of their evaluation and treatment results into a clinical research database. Information was retrospectively retrieved from the database by a research coordinator blinded to the study questions. Patient records from January 2009 to June 2014 were included if records indicated the following inclusion criteria: age older than 18 years and primary diagnosis of BMVFL (Table I). Data obtained included Voice Handicap Index-10 (VHI- 10) 4 and Cepstral Spectral Index of Dysphonia (CSID) of an allvoiced sentence of connected speech, 5 pre- and postintervention. CSID is a multifactorial estimate of dysphonia based on an algorithm of frequency-based acoustic measures. 5 Patients completed the VHI-10 at their initial evaluation visit (pretreatment). To decrease time as a confounding variable, the follow-up time points for each were selected in a 415

2 TABLE I. Definitions of Benign Midmembranous Vocal Lesions. 3 Type Vocal fold nodule Vocal fold polyp Vocal fold cyst, SE or lig Fibrous mass, SE or lig Reactive vocal fold lesion Pseudocyst Nonspecific vocal fold lesion Definition Bilateral, fairly symmetric, normal or mild impairment of mucosal wave, resolve (complete or nearly complete) with voice therapy. Unilateral or bilateral, exophytic, gelatinous material that is unorganized in the SE space. Encapsulated lesion within the SE or lig location, often associated with reduced mucosal wave, does not resolve with voice therapy. Amorphous fibrous material within the SE or lig location, often associated with reduced mucosal wave, does not resolve with voice therapy. Contralateral lesion (SE) to a fibrous mass, cyst, or polyp. Will often resolved or get smaller with voice therapy. Unilateral or bilateral superficial lesion associated with glottal incompetence (e.g., vocal fold scar, vocal fold paresis, vocal fold paralysis). High likelihood of recurrence following surgical removal if associated glottal incompetence is not addressed. Persistent unilateral or bilateral lesion following voice therapy. Lesion is not treated with surgery given the improved clinical voice function that the patient experiences from voice therapy. lig 5 ligamentous; SE 5 subepithelial. similar time period. The VHI-10/CSID closest to but not less than 3 months postsurgery and 1 month after completion of voice therapy were selected as post-treatment. Voice Therapy Intervention In general, treatment decisions to address BMVFLs were made jointly by the patient and laryngologist/speech language pathologist (SLP) team with the philosophy of using nonsurgical intervention (voice therapy and medical treatment for suspected laryngopharyngeal reflux [LPR] disease and/or sinonasal allergic disease if warranted) before contemplating surgery. Voice therapy consisted of a combination of flow phonation into resonant voice, articulatory precision, and carryover to conversational speech, as determined by the treating SLP, who individualized each voice therapy session to the patient s vocal behavior and demands. 6 Medical Intervention Treatment of LPR was provided if indicated, based on the results of a reflux symptom severity index, clinical assessment, and patient self-report of symptoms. 7 Treatment for reflux was primarily dictated by the individual patient s clinical presentation, but typically consisted of behavioral and dietary modifications and once per day proton pump inhibitor (omeprazole 40 mg), with ranitidine 300 mg taken at bedtime. Surgical Intervention If the patient remained symptomatic following maximal behavioral and/or medical intervention, they were offered microsuspension laryngoscopy with microflap excision. All procedures were performed under general anesthesia, using a cold steel microflap excision technique. 8 The need for intraoperative steroid injection was determined by the operating surgeon on a case-by-case basis; typically those lesions that extended deeply into the vocal fold (i.e., ligamentous) were more often treated with intraoperative steroid injection and/or the primary lesion was associated with adjacent scar tissue within the vocal fold. A 27-gauge orotracheal injector (Medtronic, Minneapolis, MN) was used to administer dexamethasone (10 mg/ml) in the immediate surgical site (subepithelial or vocal ligament). A typical injection volume ranged from 0.2 to 0.4 ml per vocal fold. 9 Duration of postoperative complete voice rest typically ranged from 6 to 8 days. Patients who were found to have deep, extensive lesions (i.e., ligamentous) at surgery and/or patients whose stroboscopy demonstrated postoperative severely decreased mucosal wave vibration were considered for steroid injection. These procedures were performed in the office, with the patient awake under local anesthesia. 10 Superficial injection of dexamethasone 10 mg/ml was usually performed into the vocal fold(s) involving a volume ranging from 0.1 to 0.4 ml per vocal fold. Injection was performed using a 27-gauge needle (ENF-VT2; Olympus America, Center Valley, PA) through the working channel of the flexible, distal-chip camera nasolaryngoscope (ENF-VT2, Olympus America). Patients with vocal fold nodules or NSVFLs have improvement of voice quality without surgery. Vocal fold nodules will resolve with voice therapy, whereas NSVFLs will not. Before enumerating the final breakdown of BMVFLs, video perceptual analysis was performed (L.J.S., V.N.Y., A.I.G.) to confirm the diagnoses of nodules or NSVFLs. The reviewers viewed the video stroboscopy before and after voice therapy; if lesions remained, despite the patients having improved voice quality, they were categorized as NSVFLs. If the lesions had resolved, then they were termed vocal fold nodules. Laryngostroboscopic examinations from both rigid and flexible endoscopies without audio were reviewed. As part of standard clinical care, all patients underwent audio recording while reading the all-voiced sentence We were away a year ago from the Consensus Auditory-Perceptual Evaluation of Voice 11 protocol at their most comfortable pitch and loudness in a sound-treated room. Recordings and analysis of this sentence were completed using Analysis of Dysphonia in Speech and Voice (ADSV; KayPENTAX, Montvale, NJ). 12 A research coordinator linked the pre- and post-treatment VHI-10 questionnaires summed scored to corresponding data from the connected speech sample of the all-voiced sentence and obtained >50% (n 5 134) complete data sets of pre- and posttreatment CSID measures. Cursors were placed at the onset and offset of db SPL contour tracing of the sentence We were away a year ago, and the sentence was subsequently analyzed according to the All Voice Sentence ADSV protocol specifications. 5 Means and standard deviations for all the analyses were calculated. A paired-samples t test was used to detect differences between the CSID/VHI-10, pre- and post-treatment, across all BMVFLs. Statistical analyses were performed using Excel (Microsoft, Redmond, WA). 416

3 TABLE II. Incidence of Benign Midmembranous Vocal Fold Lesions and VHI-10 Results of Treatment, N Polyp FM-lig FM-SE cyst-lig cyst-se NSVFL Nodules Pseudocyst No Mean age, yr Gender F 5 65%, M 5 35% F 5 80%, M 5 20% F 5 69%, M 5 31% F 5 80%, M 5 20% F 5 83%, M 5 17% F 5 93%, M 5 7% F 5 58%, M 5 42% F 5 100%, M 5 0% Incidence 30.8% 4.5% 21.4% 4.5% 5.4% 24.1% 8.5% 0.9% Pre VHI Post VHI D VHI P % change 65.1% 25% 55.9% 52.6% 67.9% 36.4% 51.7% % with normal VHI-10 post-treatment 64.80% 20% 56.30% 50% 66.70% 58.20% 63.20% % change 5 percentage change of VHI-10 score following treatment (pretreatment 2 post-treatment/pretreatment); D VHI-10 5 delta VHI-10 score (pretreatment VHI-10 2 post-treatment VHI-10); Cyst 5 vocal fold cyst; F 5 female; FM 5 fibrous mass; M 5 male; lig 5 ligamentous; Nodules 5 vocal fold nodules; NSVFL 5 nonspecific vocal fold lesion; Polyp 5 vocal fold polyp; Post VHI-10 5 posttreatment VHI-10; Pre VHI-10 5 pretreatment VHI-10; SE 5 subepithelial; VHI-10 5 Voice Handicap Index-10. RESULTS Two hundred and fifty-one patients met the inclusion criteria. Sixteen patients were removed from the study cohort due to lack of follow-up or absent key evaluation data points. Eleven additional patients were removed because they were treated with an in-office pulsed potassium titanyl phosphate laser treatment approach and thus were not able to be given a definitive diagnosis. Our final study cohort consisted of 224 patients (Table II). The mean follow-up for the nonsurgical patient group was 2.58 months (range months). The mean follow-up for the surgical patient group was 5.7 months (range months). Seventy-one percent of patients (n 5 160) had voice therapy following phonomicrosurgery, with a mean number of 3.06 (range 5 1 8) voice therapy sessions. For the nonsurgical patients (nodules and NSVFLs) the average number of voice therapy sessions was 4.11 (range ). Sixty-seven percent of all patients with a BMVFL underwent phonomicrosurgery. Incidence of nonsurgical treatment (voice therapy) as sole treatment was 33%. The three most common BMVFL types were polyp (30.8%), NSVFL (24.1%), and FM-SE (21.4%). These three lesions represented 76% of the study cohort. Pseudocyst represented only 0.9% of the group. A quarter of all surgical patients underwent intraoperative steroid injection(s), and 15% received postoperative steroid injection(s). Approximately half of all fibrous mass (both subepithelial and ligamentous) patients received intraoperative steroid injection, and 60% of FMlig patients also required postoperative steroid injection(s). Patients with all other types of BMVFL underwent steroid injection in 25% or fewer cases (Table III). Detailed analysis of the FM-lig patients by those who received steroid injection (intra- and postoperative) versus no steroid revealed that there was no difference (intraoperative delta VHI vs. no steroid delta VHI ) in the mean postoperative VHI-10 and delta VHI-10 for the intraoperative steroid patients. For the FM-lig patients who received postoperative steroid injections, the delta VHI-10 was 6.5; in comparison, for the FM-lig patients who did not have postoperative steroid injections the delta VHI-10 was 3.5. All diagnostic groups had a significant positive response to all treatments based on comparison of the TABLE III. Use of Intraoperative and Postoperative Superficial Dexamethasone (10 mg/ml) Vocal Fold Injection. Lesion Type No. Intraoperative Injections, No. (%) Patients Receiving Postoperative Injections, No. (%) No. of Patients With Total No. of Postoperative Injections Polyp 71 4 (5.6) 7 (9.9) 5 patients w/ 1 injection, 1 patient w/ 2 injections, 1 patient w/ 4 injections FM-lig 10 5 (50) 6 (60) 3 patients w/ 2 injections, 2 patients w/ 3 injections, 1 patient w/ 4 injections FM-SE (48) 3 (2.1) 2 patients w/ 1 injection, 1 patient w/ 2 injections Cyst-lig 10 3 (30) 4 (40) 2 patients w/ 1 injection, 2 patients w/ 2 injections Cyst-SE 12 3 (25) 2 (16.7) 1 patient w/ 1 injection, 1 patient w/ 2 injections Total (25) 22 (14.6) 10 patients w/ 1 injection, 8 patients w/ 2 injections, 2 patients w/ 3 injections, 2 patients w/ 4 injections Cyst 5 vocal fold cyst; FM 5 fibrous mass; lig 5 ligamentous; Polyp 5 vocal fold polyp; SE 5 sub-epithelial. 417

4 Diagnosis TABLE IV. Treatment Outcome by Diagnosis and Delta VHI-10. No. Patients w/d VHI 5 Patients w/d VHI Patients w/ Zero or Negative D VHI change Polyp (90%) 4 (6%) 3 (4%) FM-lig 10 4 (40%) 4 (40%) 2 (20%) FM-SE (81%) 7 (15%) 2 (4%) Cyst-lig 10 9 (90%) 1 (10%) 0 (0%) Cyst-SE (100%) 0 (0%) 0 (0%) NSVFL (56%) 13 (24%) 11 (20%) Nodules (68%) 3 (16%) 3 (16%) D VHI-10 5 pretreatment VHI-10 2 post-treatment VHI-10 score; Cyst 5 vocal fold cyst; FM 5 fibrous mass; lig 5 ligamentous; Nodules 5 vocal fold nodules; NSVFL 5 nonspecific vocal fold lesion; Polyp 5 vocal fold polyp; SE 5 subepithelial; VHI-10 5 Voice Handicap Index-10. pre- and post-treatment mean VHI-10 scores (Table II). The largest mean changes in VHI-10 score following phonomicrosurgery treatment were in the cyst-se, polyp, and FM-SE diagnoses. The FM-lig group had the smallest response on the VHI-10 (mean pre post) and percentage change in VHI-10 score among all the diagnostic groups. Arffa et al. determined that a VHI-10 score < 11 was normal. 12 The mean post-treatment VHI-10 score of all treatments across all the diagnostic groups, except FM-lig, were within normal limits. Analysis of the percentage of patients in each diagnostic group with a posttreatment VHI-10 score < 11 revealed that the majority in all groups had a post-treatment VHI-10 < 11 (Table II), except FM-lig. Evaluation of the individual patient treatment results using the delta VHI-10 (pretreatment VHI post-treatment VHI-10) reveals that the overall degree of treatment success is quite high (Table IV). Specifically, polyp, FM-SE, cyst-lig, and cyst-se patients had a rate of delta VHI-10 > 5, ranging from 81% to 100%. A delta VHI-10 of 5 has been used in past studies as representing a presumptive clinical difference. 13 This is similar to the grouped mean VHI-10 results. The nonsurgical lesions (nodules/nsvfls) appear to have a lower success rate as judged by only having an incidence of delta VHI-10 5 of 68% and 56%, respectively. On a related note, 20% of the NSVFL patients had a delta VHI-10 of zero or a negative number (Table IV). Given the substantive number of NSVFL patients with a delta VHI-10 < 5 (24 of 54), detailed analysis of the VHI-10 and CSID results was performed. CSID data (pre/post) was available for 36 of the 54 NSVFL patients. From these 36 NSVFL patients with complete CSID data sets, 16 patients had a delta VHI-10 < 5. The posttreatment CSID was in the normal range for 15 of the 16 patients. Of the entire NSVFL cohort, 13 patients had a delta VHI-10 between 4 and 1, and 11 had a delta VHI-10 of zero or negative. Of the former group, only four of the 16 patients had a post-treatment VHI-10 > 10 (abnormal). The latter had six patients with a posttreatment VHI-10 > 10 (abnormal). The CSID analysis (by gender) was performed on 134 of the 224 patients in the study group. For the entire CSID Data TABLE V. CSID Results by Treatment and Gender. No. Mean Pre-CSID Mean Post-CSID t P Total Male Female Surgical Male Female Nonsurgical Male Female CSID 5 Cepstral Spectral Index of Dysphonia. study group, a significant difference was found in CSID (P 5.006; Table V). For the patients who had surgical intervention (n 5 85), a significant difference was found in CSID (P 5.002). However, for female patients (n 5 44) in the nonsurgical group (NSVFLs and nodules), there was no significant difference in CSID (P ; Table V). DISCUSSION This study demonstrated a high degree of treatment success in a cohort of patients with strictly defined BMVFLs using validated and objective outcome measures. Previous studies have been limited by either lack of clearly defined BMVFL delineations and/or lack of validated or objective outcomes For all BMVFL diagnostic groups other than FM-lig, treatment resulted in mean final VHI-10 scores within the normal range (<11). The lesions treated without surgery (nodules/ NSVFLs) had less of a reduction in VHI-10 following treatment; however, patients in these groups had lower VHI-10 scores at baseline compared to the surgically treated BMVFLs (Table II). The pre-/post-treatment VHI-10 scores in the current study reflect findings from our past reports of patients with BMVFLs (Table VI). 3 Voice handicap improved the least in patients with FMlig compared to the other BMVFL categories. The relatively reduced treatment response may be due to the more extensive derangement of the vocal fold lamina propria associated with these lesions and/or the more extensive surgical dissection to remove the pathologic TABLE VI. Mean Voice Handicap Index-10 Results of Previous and Current Studies for Vocal Nodules and NSVFLs. Study Nodules Pre-Tx Nodules Post-Tx NSVFLs Pre-Tx NSVFLs Post-Tx Previous Current Nodules 5 vocal fold nodules; NSVFL 5 nonspecific vocal fold lesion; Pre-Tx 5 pretreatment; Post-Tx 5 post-treatment. 418

5 tissue. These results can help clinicians provide patients with important prognostic information, and establish reasonable treatment result expectations. Furthermore, these findings may have substantive implications for treatment decision making and treatment implementation (i.e., lower threshold to utilize intra- and postoperative steroid injections). The acoustic data showed that, for the entire study cohort, pre-/post-treatment CSID scores showed a significant improvement. All CSID scores were in the normative range based on norms for CSID from ADSV. However, for female patients in the nonsurgical group (NSVFLs and nodules), there was no significant difference in CSID, perhaps due to the low pretreatment CSID scores (i.e., the pretreatment mean CSID score in the current study was 6.47 and the mean normative value score for females is 6.44). On the surface, results of the current study support the voice improvement observed in other studies of BMVFLs. For example, Schindler and colleagues reported the results of voice therapy on patients with Reinke s edema, vocal fold cyst, and gelatinous polyp. 17 Despite the large cohort, standardized voice therapy approach, and detailed outcome assessment, little can be concluded (and compared to the present study) due to the lack of definitions of BMVFLs present in their paper. Without operationally defining BMVFLs, results are incomparable between studies, and are also not replicable. Similarly, Estes and Sulica reported a retrospective report of patients diagnosed and treated with pseudocyst in This paper highlights the value of using a BMVFL nomenclature system that is comprehensive of all BMVFLs and use of strictly defined parameters that are not subjective. The article uses the term phonotraumatic as part of their pseudocyst definition, although that term is not defined nor uniformly understood as well as is presumptive in etiology. Detailed review of the paper s patient cohort reveals that 41% of the patients had a diagnosis of paresis and a large majority of the patients experienced improvement with voice therapy as sole treatment. Unfortunately, the vocal fold pathology status of the latter group (voice therapy only) is not provided. It is conceivable to conclude from their report that these cases of pseudocyst would have been classified as either NSVFLs or vocal nodules in the current study and the patients who went to surgery would have been classified as vocal fold polyps. A similar situation exists when Estes and Sulica report their surgical results in patients with pseudocyst from a prospective study. 19 This study involves 17 patients who had BMVFL descriptions compatible with a vocal fold polyp. Their treatment outcomes are very similar to the present study. They report a pretreatment mean VHI-10 of (the current study polyp group was 22.69), and they report a posttreatment VHI-10 of 5.12 (the current study polyp group was 7.19). 19 The present study showed a 20% increase in polyp diagnosis compared to our previous study, which resulted in subsequent changes to the incidence of surgical versus nonsurgical treatment. 3 Our previous data set had a 67% incidence of nonsurgical treatment compared to 33% for the present study. The differences in diagnosis incidence may be explained by the small study cohort of the first investigation. The NSVFL results show that this patient group generally started with a lower VHI-10 pretreatment score than the surgical group. Furthermore, many of these patients who had a delta VHI-10 < 5 ended with a normal VHI-10 score. There were only 10 (of 54) NSVFL patients who had a post-treatment VHI-10 that was abnormal. This may represent individuals who were willing to live with their vocal handicap due to a variety of issues (e.g., afraid of surgery, good tolerance of vocal handicap, reduced voice demands). Comparison of the FM-lig patients who received or did not receive steroid injections (intra- and/or postoperative) is limited due to size (n 5 10), and the potential for a significant selection bias exists. This study has a number of limitations in addition to its retrospective nature. The nomenclature system does not account for patients treated with in-office laser treatment. The NSVFL diagnosis encompasses a variety of potential final diagnoses (polyp, cyst, or fibrous mass), and this diagnosis may represent a hybrid of patients who clinically improved with nonsurgical treatment without resolution of the vocal fold pathology. It is unknown whether, with further behavioral and/or surgical treatment, the NSVFL patients would show additional improved treatment results. It is also important to remember that several diagnoses (FM-lig, cyst-lig, and cyst-se) had small numbers, which limits our ability to accurately compare treatment results with the other diagnostic groups. CONCLUSION This study further validates previously proposed a nomenclature paradigm for classification of various BMVFLs and provides detailed treatment outcomes for strictly defined BMVFLs. The results can guide clinicians counseling on prognosis of voice outcome based on the specific BMVFL diagnosis. The findings of this study demonstrate that a high degree of functional recovery can be expected for a large majority of patients with BMVFLs. In addition, it raises awareness that patients with FM-lig have a lower treatment success rate and thus these patients may require a different treatment approach in the future. These results will allow future studies to compare different treatment methods and accurately measure outcome of these treatments. BIBLIOGRAPHY 1. 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