Introduction
This article discusses a case of redundant mucosa of the arytenoids and aryepiglottic folds in an adult with severe OSA. The pathology was identified and diagnosed using drug-induced sleep endoscopy and represents the first reported case where this procedure has been used to identify this pathology. In presenting this case, we also discuss the literature regarding potential aetiology and available treatments.
Redundancy of supraglottic and laryngeal mucosa and its association with obstructive sleep apnoea (OSA) is an exceedingly rare condition. There is relative paucity in the literature involving this pathology. While published reports discuss the relationship between the redundant mucosa and OSA, many have an identifiable aetiology or are observed during the awake patient state, therefore not representing the effect of the excess tissue on OSA.Reference Purser, Irving and Marty1–Reference Rodriguez Adrados, Esteban Ortega and Peña Griñán4
Herein, we describe the clinical presentation, management and first videographic evidence of idiopathic excess mucosa around the aryepiglottic folds causing OSA, as well as its appearance following correction, identified during drug-induced sleep endoscopy. In doing so, it offers a contemporary description of redundant laryngeal mucosa associated with OSA, emphasising the potential of drug-induced sleep endoscopy as a novel diagnostic and investigative tool. We present the following article in accordance with the CARE reporting guidelines (https://www.care-statement.org).
Case report
The patient was an otherwise well, 40-year-old male, who presented to the clinic with a 2-year history of snoring, apnoea and daytime hypersomnolence (sleeping up to 18 hours and remaining tired), with effects on occupation and personal relationships. He was also observed to fall asleep during the pre-operative anaesthetic assessment. He had a history of hay fever and anxiety, and a previous adenotonsillectomy in childhood. His medications included sertraline, antihistamines and steroid nasal spray. He previously trialled full-mask continuous positiveairway pressure (CPAP) without improvement to daytime somnolence level. He smoked a packet of cigarettes daily and had no significant alcohol history. On examination, he was a non-overweight individual with a bulky tongue and normal lingual tonsils. The patient did not have an awake stridor. Flexible nasopharyngoscopy shows enlarged inferior turbinates, with a left septal deviation. The hypopharynx and oropharynx were unremarkable.
The patient underwent elective drug-induced sleep endoscopy. Snoring was observed to occur with preferential mouth breathing by the patient, which improved progressively with mouth closure and jaw advancement. There were periods of apnoea lasting more than 10 seconds. The patient was found to have a bulky tongue base as well as lateral wall collapse contributing to the apnoea. While there were no prominent lingual tonsils, there was occasional palatal flutter with incomplete circumferential collapse contributing to snoring.
Redundant mucosa of the arytenoids and posterior commissure was observed in the larynx. These were found to occlude the laryngeal inlet during inspiration resulting in apnoeic episodes (Supplemental Data: Video 1). Intranasally, there was a left-sided cartilaginous septal deviation and bilateral inferior turbinate hypertrophy.
The patient underwent endoscopic septoplasty and turbinoplasty. He subsequently had radiofrequency palatal stiffening and tongue base reduction with six and nine lesions, respectively. Direct microlaryngoscopy was then performed; 2 mL of 2 per cent Xylestesin submucosal infiltration, with subsequent ablation of the redundant mucosa of the arytenoids and posterior commissure with a 20 W suction monopolar (Figures 1 and 2).
Intraoperative image during treatment demonstrating supraglottic collapse with redundant mucosa prolapsing into the laryngeal inlet, obstructing the airway (see Supplementary Video 1, journals.cambridge.org).
Post-treatment image showing a patent airway with resolution of the previously observed supraglottic obstruction following surgical ablation of redundant mucosa (see Supplementary Video 2, journals.cambridge.org).
The patient had good recovery following surgery, with subsequent drug-induced sleep endoscopy confirming resolution of the anatomical obstructions contributing to his OSA and no apnoeic episodes observed during the procedure (Supplemental Data: Video 2). He reported resolution of his snoring and daytime hypersomnolence, leading to a marked enhancement in his quality of life, enabling him to maintain his work as a builder. Nearly four years post-treatment, the patient remains clinically well, with no reported recurrence or adverse effects.
Discussion
The pathophysiology of developing redundant supraglottic mucosa is poorly understood, and few theories have been proposed. Although, morphologically, the appearance of redundant supraglottic mucosa has been likened to paediatric laryngomalacia, the underlying pathological formation has different etiological drivers, as well as being a purely mucosal, rather than a cartilaginous disease process.Reference Purser, Irving and Marty1, Reference Rutt, Dworkin and Stern2 This entity is also separate from adult-onset laryngomalacia, which has clear pathophysiological processes linked to iatrogenic causes such as head and neck surgeries/radiation, or flaccidity caused by hypotonia due to neurologic insults.Reference Siou, Jeannon and Stafford3
Purser et al. postulated that this redundant supraglottic mucosa is most likely a consequence of sub-atmospheric pressures in the airway below the site of obstruction in OSA.Reference Purser, Irving and Marty1 This theory was based on the case reports they described and similar outcomes between both patients, one of which received a surgical intervention alongside nasal CPAP, and the other received nasal CPAP alone.Reference Purser, Irving and Marty1 Both patients were observed to have complete resolution and no recurrence of the redundant tissue. Although this was an interesting finding, similar results have not been found in other case reports where CPAP was also trialled,Reference Rutt, Dworkin and Stern2, Reference Rodriguez Adrados, Esteban Ortega and Peña Griñán4 including the current report. This pathophysiological theory, although compelling, is inconclusive without further longitudinal evaluation of the causative relationship between OSA and supraglottic mucosal redundancy.
Idiopathic redundant supraglottic and laryngeal tissue associated with sleep-disordered breathing has seen limited discussion in the literature. The first description by Purser et al. reported two patients with disrupted sleeping and snoring and findings of redundant swollen mucosa extending from the arytenoid cartilages and aryepiglottic folds into the lumen of the laryngeal inlet.Reference Purser, Irving and Marty1 A review of the published literature provides two similar case reports of patients with OSA-related redundant supraglottic mucosa.Reference Rutt, Dworkin and Stern2, Reference Siou, Jeannon and Stafford3 A further case series reviewing the occurrence of “Shar Pei larynx” in patients with OSA, identified another 22 patients over a 5-year period.Reference Rodriguez Adrados, Esteban Ortega and Peña Griñán4
Many of these studies used awake flexible laryngoscopy to identify supraglottic redundant tissue; currently, this often occurs after other therapies for other diagnoses are trialled with minimal success, which prompts clinicians to investigate further for other causes. Consequently, the number of patients with redundant supraglottic tissue may not be accurately represented in the literature. Many patients with OSA are diagnosed via polysomnography and may therefore never have direct imaging of the laryngeal airways, which may lead to an under diagnosis of this condition. Hence, patient response to conservative therapy may be limited. This was seen by Yiu et al. whose retrospective analysis identified a considerable number of patients with this redundant tissue associated with OSA.Reference Yiu, Tibbetts, Simpson and Matrka5
Drug-induced sleep endoscopy is a procedure that allows for the examination of the upper airway in patients with sleep-disordered breathing using an anaesthetic and an endoscope. This procedure sedates the patient into a sleep-like state, as monitored by EEG, and therefore preserves the near-physiological airway reflexes that are present during sleep. Endoscopic instruments are passed through the patient’s upper airway to identify the site and pattern of narrowing and obstructions that are contributing to snoring and apnoeic episodes.Reference De Vito, Carrasco, Ravesloot, Kotcha, De Vries and Hamans6
The literature suggests that the incidence of redundant laryngeal tissue and its association with sleep-disordered breathing may be higher than expected.Reference Rodriguez Adrados, Esteban Ortega and Peña Griñán4 This suggests that routine intra-operative examination of the glottis during drug-induced sleep endoscopy is worthwhile. As described in the present report, effective treatment of this pathology is available.
The authors therefore suggest the use of the drug-induced sleep endoscopy procedure to examine down to the larynx beyond the epiglottis before committing to other surgical management in order to investigate for the presence of redundant mucosa of the arytenoids and supraglottic region. The updated European position paper indicates that the nose and nasopharynx do not hold the same level of importance in OSA as previously thought, and the investigation of these locations is easily achieved during the awake state.Reference De Vito, Carrasco, Ravesloot, Kotcha, De Vries and Hamans6 The larynx however, as seen by the literature presented, may play a larger role in OSA. This is in line with the Nose Oropharynx Hypopharynx and Larynx classification, which examines from the nasal passage down to the larynx and allows for more consistent classification between both awake fibreoptic examinations and sleep endoscopies.Reference Vicini, De Vito, Benazzo, Frassineti, Campanini and Frasconi7 Intra-operative examination of the larynx and glottis will help further elucidate the incidence of redundant supraglottic mucosa, which can be easily treated in conjunction with drug-induced sleep endoscopy. This should lead to patients achieving symptom resolution earlier and with fewer investigations or surgeries.
∙ Redundant supraglottic and laryngeal mucosa contributing to obstructive sleep apnoea is an exceedingly rare pathology
∙ This report presents a novel case and a contemporary description of redundant laryngeal mucosa associated with obstructive sleep apnoea alongside videographic evidence pre- and post-treatment
∙ Drug-induced sleep endoscopy may provide a useful tool to diagnose patients with this condition
∙ A standardised approach for examination down to the larynx when performing drug-induced sleep endoscopy may identify more patients with this pathology earlier
Conclusion
This article presents a rare case of redundant arytenoid and aryepiglottic mucosa associated with OSA, highlighting the diagnostic and therapeutic value of drug-induced sleep endoscopy. The case demonstrates successful OSA management through ablation of the redundant tissue. These findings underscore the importance of laryngeal examination during drug-induced sleep endoscopy to accurately identify and address redundant supraglottic mucosa in OSA patients. This article contributes to our understanding of this rare pathology and informs potential treatment strategies. Further research and longitudinal evaluations are necessary to better comprehend the underlying mechanisms and refine optimal management approaches.
Acknowledgments
We thank Grace Hospital Tauranga for their assistance in collecting the data required to write this manuscript.
Funding
The authors have no funding to report.
Competing Interests
The authors have no conflicts to declare.
