Resolution of Muscle Tension Dysphonia with Reinke’s Edema Following STRETTA Therapy in a Patient with GERD: A Case Report

Muscle Tension Dysphonia (MTD) is a syndrome involving abnormal vocal cord behaviour due to increased tension of laryngeal musculature. It has a complex etiology, but gastroesophageal reflux disease (GERD) is implicated in up to half of cases. The authors present the first reported case of MTD being successfully treated using STRETTA,

Her symptoms failed to improve despite incision and drainage of the Reinke's edema. An EGD demonstrated reflux esophagitis, and a blunt angle of His. She underwent STRETTA and reports significant improvement of symptoms. Repeat nasoendoscopy showed convalescence of the Reinke's edema. Existing evidence suggests that management of MTD with proton pump inhibitor (PPI) improves reflux symptoms such as chronic cough and heartburn but has a limited effect on measures of voice such as voice range profile, perceptual evaluation, and acoustic analysis. Given that the present patient found subjective improvement in voice quality, it is possible STRETTA may be preferable to PPI in treating MTD with regard to voice, but further assessment of voice quality pre-and post-STRETTA is needed. In LPR refractory to PPI, there is evidence that Laparoscopic Nissen Fundoplication (LNF) is successful; however, the cost-effectiveness of endoscopic anti-reflux procedures such as STRETTA is superior to operative management such as LNF. Therefore, STRETTA may well be more beneficial than both PPI and LNF in the treatment of MTD with LPR.
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Background
Muscle Tension Dysphonia (MTD) is a syndrome with a variety of etiologies leading to abnormal vocal fold behaviour as a result of increased tension of laryngeal musculature [1]. It is subdivided into primary and secondary, the latter whereby the cause is related to structural or neurogenic abnormality. Primary causes are often multifactorial relating to functional disorders, allergy, and gastrointestinal reflux, with gastroesophageal reflux disease (GERD) a predominant co-morbidity (40-49% of cases) [2,3].
LPR is managed with proton pump inhibitors (PPI); however, it is accepted that PPI is less effective for LPR than for typical GERD symptoms [6]. In addition, anti-GERD lifestyle modifications are recommended; these include avoidance of trigger foods, weight loss, reduction of portion size, cessation of alcohol and smoking, avoiding eating immediately before going to bed, and raising the bed head.
Treatment techniques for MTD such as injection laryngoplasty and transcutaneous electrical nerve stimulation, often in combination with vocal therapy, are widely accepted as the gold standard treatment [7][8][9]. These treatments can result in a positive outcome, though rarely result in complete symptom resolution [7].
STRETTA is a novel endoscopic anti-reflux therapy that uses radiofrequency to stimulate hypertrophy at the gastroesophageal junction (GEJ), augmenting the GEJ to prevent reflux of gastric contents into the esophagus [10]. It has excellent outcomes in patients with GERD [11,12]. STRETTA is the only radiofrequency anti-reflux therapy approved by NICE for use in the UK [10]. Here, we report the first case of MTD successfully treated with STRETTA therapy.

Case Report
A 60-year-old female had been under follow up from both the ENT and gastroenterology team at James Cook University Hospital since 2016. She had a past medical history of Raynaud's disease. Since 2016, she had symptoms of LPR. These included dysphonia, cough, sore throat, and persistent throat clearing. In early 2017, she underwent flexible nasendoscopy, which demonstrated significant posterior laryngeal edema, and anterior-posterior constriction on phonation, suggestive of MTD. In light of these findings, she was initiated on PPI and Gaviscon Advance.  In November 2019, she was referred to the upper GI surgical team for further assessment. A repeat Esophagogastroduodenoscopy (EGD) demonstrated a lax GEJ with retrograde prolapse of gastric mucosa, evidence of reflux oesophagitis, and a blunt angle of His (Figure 1). She also underwent barium swallow, which demonstrated evidence of esophageal dysmotility, there were subtle uncoordinated, non-peristaltic contractions of her esophagus with slow transit on prone swallow, but her esophagus eventually cleared when in an erect position. Her DeMeester score was equivocal. Her 24 hr pH study result was equivocal, and manometry showed preserved peristalsis with a relaxing lower esophageal sphincter (LES) zone. She underwent STRETTA therapy in January 2020, under conscious sedation. Forty-nine out of a total of 56 radiofrequency thermal treatment points were successfully delivered ( Figure 2). Due to the COVID-19 pandemic, her post-procedure follow-up was via the telephone 4 months after treatment. She reported, feeling much better with improvement in her GERD HRQL scores. Specifically, she reports less acid taste in her mouth along with improvement in her voice, that was normal on the phone, and the patient states her voice has improved. She had a repeat nasendoscopy under ENT, which showed convalescence of the Reinke's edema. She no longer takes a PPI but does continue to take Gaviscon Advance as and when required, after meals and before bed.

Discussion
Although STRETTA has been documented to reduce hoarseness and voice changes associated with GERD, based upon current published literature, we believe this case to be the first report of the use of STRETTA to successfully treat MTD with LPR [13].
In patients presenting with otolaryngeal symptoms, silent gastroesophageal reflux is often present. Where a patient has a normal pH profile and no reflux symptoms, PPI is of no benefit [14]. On the other hand, where patients have abnormal pH and/or reflux symptoms, PPI improves reflux symptoms such as dysphonia, dysphagia, globus, chronic cough and heartburn [14]. However, PPI has a limited effect on measures of voice such as voice range profile, perceptual evaluation, and acoustic analysis [14,15]. Given that the present patient found subjective improvement in voice quality, it is possible STRETTA may be preferable to PPI in treating MTD with regard to voice, but a further assessment of voice quality pre-and post-STRETTA is needed. This patient had GERD symptoms persisting despite PPI therapy; this has been shown to occur in 15% of patients with LPR [15]. Given the prevalence of LPR, there are a substantial number of patients with refractory LPR despite PPI that could benefit from STRETTA.
In LPR refractory to PPI, there is evidence that Laparoscopic Nissen Fundoplication (LNF) is successful, with 61% reporting no or only mild laryngitis and 69% had an improved voice quality following surgery [16]. The cost-effectiveness of endoscopic anti-reflux procedures such as STRETTA is superior to operative management such as LNF and becomes more favourable compared with PPI when high doses and longterm therapy is needed [17,18]. Patients with LPR often require prolonged courses of high dose PPI, and unfortunately, many suffer relapse upon stopping therapy [19]. Therefore, in cases of LPR, STRETTA may be more cost-effective and confer a more durable benefit when compared to life-long high dose PPI, or more invasive surgical procedures with the higher potential risk profile.
To our knowledge, this is the first documented case of muscle tension dysphonia successfully treated with STRETTA therapy. This has resulted in symptom resolution and reduced the patient's medication burden. Further work is needed to confirm if STRETTA should be used routinely in patients with muscle tension dysphonia.