Abstract
Surgical treatment of OSA has emerged as an effective alternative in continuos positive airway pressure (CPAP)-non-compliant group of patients. The present study examines the outcomes following a combination of barbed palatopharyngoplasty (BPP) and endoscopic coblator-assisted midline partial glossectomy in patients with multilevel obstruction of palate, oropharyngeal walls, and tongue base. A retrospective study of 40 patients with predominant obstruction at the velum, oropharyngeal lateral walls, and base of tongue levels, who underwent Barbed Palato Pharyngoplasty and Endoscopic coblator-assisted tongue base resection. Preoperative and post-operative Epworth Sleepiness Score (ESS), and Visual Analog Score (VAS) for snoring. Apnoea-Hypopnoea Index (AHI) and lowest oxygen saturation(L-Sat) were assessed by polysomnography. Improvement in qualityof life parameters were also evaluated. According to the AHI score, 55% of patients had severe OSA, while 45% of patients had moderate OSA. Sleep parameters like AHI, lowest oxygen saturation, and VAS score for snoring significantly improved after surgery (<0.0001). The overall success rate was 62.5%, according to Sher criteria. Following surgery, quality of life improvement in patient centered parameters was also observed in this study. Multilevel surgery with barbed palatopharyngoplasty combined with coblator-assisted midlie glossectomy is an effective treatment modality in patients with moderate-tosevere OSAS. The efficacy of combined surgical treatment was evidenced by improvements in PSG results and patient-centered quality of life parameters.
Keywords: Obstructive sleep apnoea, Sleep surgery, Barbed palatal surgery, Coblation midline glossectomy, Obstructive sleep apnoea surgery, Lateral pharyngoplasty, Anterior palatoplasty
Introduction
Obstructive sleep apnea (OSA) is recognized as a serious health problem and results from episodes of complete or partial obstruction of the upper airway. Although CPAP is considered the first-line therapeutic option for OSA, its adherence remains unacceptably low, highlighting the need for other modalities of treatment [1, 2]. Surgical treatment of OSA has emerged as an effective alternative for a well-selected CPAP-non-compliant group of patients [1].
Impairment in pharyngeal anatomy (narrow or collapsible airway), along with low arousal threshold, high loop gain, and poor muscle responsiveness, have been recognized as causative factors in the pathogenesis of OSA (30). Among these, upper airway collapsibility is a key factor that responds well to focused surgical intervention of various collapsing anatomical segments. Palate, oropharyngeal walls, and tongue base are the most frequent sites of obstruction [3, 4], and multilevel obstruction involving these sites is common. The present study is designed to describe the outcomes following a combination of barbed palatopharyngoplasty (BPP) [5] and endoscopic coblator-assisted midline partial glossectomy in patients with multilevel obstruction of the above sites. Besides changes in polysomnographic data, sleep disorders like OSA disrupt the quality of life of the affected individual. Polysomnography (PSG), the commonly used diagnostic investigation, does not reflect these changes. This study examines improvements in patient-centered parameters following surgery, in addition to PSG changes.
Materials and methods
This is a retrospective study of 40 patients with predominant obstruction at the velum, oropharyngeal lateral walls, and base of tongue levels who underwent multilevel surgery for OSA at a tertiary care hospital from May 2017 to September 2021.
All patients had non-compliance with CPAP. The study protocol included a complete medical history and clinical examination, with the following variables: sex, age, BMI [6], neck circumference, tonsil grade, Friedman tongue position [7], preoperative and postoperative Epworth Sleepiness Score (ESS) [8], and Visual Analogue Score (VAS) for snoring. We have also included patient-centered parameters like daytime tiredness, quality of sleep, frequency of apneic episodes, and control of comorbidities like diabetes mellitus and hypertension. Further clinical evaluation was performed using an awake flexible nasopharyngoscopy in the office. Apnoea-Hypopnoea Index (AHI) and lowest oxygen saturation (L-Sat) were assessed by polysomnography. Drug-induced sleep endoscopy (DISE) was done to assess the anatomical sites, grades, and patterns of upper airway collapse and recorded according to the VOTE classification system [9, 10]. Grade 0 is for no obstruction, Grade 1 is for partial obstruction, and Grade 2 is for complete obstruction. The pattern of collapse may be anteroposterior, lateral, or concentric.
Barbed Palato Pharyngoplasty [BPP] [5] was performed for all patients in this study, and they had a VOTE score of ≥ 1 on DISE with a pattern of antero-posterior, lateral, or concentric collapse of the velum and collapse of the lateral oropharyngeal walls. Endoscopic coblator-assisted tongue base resection was also performed in all patients since they had partial or complete obstruction at the tongue base level during DISE (VOTE score of ≥ 1). All patients were reassessed using polysomnography with AHI, lowest oxygen saturation (L-Sat), ESS, and VAS for snoring six months after surgery.
Surgical Procedure
The procedure was done in a single sitting under general anesthesia with naso-tracheal intubation. A Boyle-Davis mouth gag was applied, and the palatopharyngeus muscles were exposed by an intracapsular tonsillectomy. Following this, BPP was carried out, which included an anterior palatoplasty and a lateral pharyngoplasty. A single 2/0 polydioxane bidirectional barbed suture 26 × 26 cm in length with two needles (Stratafix) was used for this purpose. Anterior palatoplasty was carried out in the soft palate midway between the posterior nasal spine and base of the uvula.
The tongue was pulled forward to expose its base, and the gag was reapplied. Coblator-assisted dissection was done in the midline base of the tongue caudal to the circumvallate papillae using an Evac70/Procise-Max wand until the vallecula and epiglottis were clearly visible. Coblation was started beyond the foramen caecum, 1–1.5 cm on either side of the midline, taking care to avoid the neurovascular bundle of the base of the tongue. Tongue base tissue, including the muscles over the midline, was ablated. In cases with lingual tonsil hypertrophy causing obstruction, it was coblated and reduced. Hemostasis was achieved using bipolar cautery. All surgical procedures were done by a single surgeon.
The most common postoperative complications were pain and dysphagia in the immediate postoperative period. This was managed with non-steroidal anti-inflammatory agents and a paracetamol infusion, and it was markedly reduced by 72 h. Sedating analgesics were not used by any of the patients. Major complications, such as respiratory distress, occurred in one patient in the immediate post-operative period. Tracheostomy was done, and the patient was stabilized and weaned off after 48 h. Tongue edema was observed in 5 patients, and delayed planned extubation was carried out in them after the edema settled. One patient had secondary bleeding from the tonsilar region 5 days after the surgery, which required suturing under anesthesia. Three patients had minor bleeding from the tonsillar fossa in the first postoperative week, which settled with conservative methods. None of the patients had bleeding from the tongue base. Three patients developed mucosal granulations at the anterior palatoplasty site (7.5%), which eventually healed. Extrusion of pieces of suture material was experienced in eight cases (20%). Minor complications like diminished taste and foreign body sensation in the throat were experienced by some patients, which were relieved in 4 to 6 weeks. None of the patients had venous incompetency or difficulty clearing the postnasal secretions.
Statistical Analysis
Data were recorded in Microsoft Excel Workbook 2019 and analyzed using SPSS v21.0. Categorical variables were presented as frequencies and percentages and compared using the Chi square test. Quantitative variables were expressed as mean and standard deviation and compared using an independent t-test between two groups or a paired t-test (within a group). P < 0.05 was considered statistically significant.
Results
Among the patients who underwent multilevel OSA surgery during this period, both BPP and endoscopic coblator-assisted midline glossectomy were carried out in a single stage in 40 patients. The mean age was 43.15 ± 10.55 years, with 62.5% of patients aged ≤ 40 years. The male-to-female ratio was 1.8:1. The mean BMI was 31.5 ± 6.89 kg/m2, 92.5% of patients were obese (≥ 25), and none of the patients were normal or underweight [1]. Neck circumference was ≥ 40 cm in 57.5% of patients, and 47.5% of patients had tonsil sizes 3 and 4. Retropalatal collapse was complete in 90% of patients. Retroglossal obstruction was complete in 82.5% of patients. Freedman tongue position was between 3 and 4 in 42.5% of patients with a high tongue base. For 5% of patients, the ESS score was zero, and 12.5% of patients had an ESS score of < 10. The VAS score was more than 5 in 90% of patients. According to the AHI score, 55% of patients had severe OSA, while 45% of patients had moderate OSA.
All patients underwent pre- and postoperative (6-month-later) PSG. The surgical success rate was measured according to the Sher criteria. (AHI < 20/h with ≥ 50% AHI improvement) The success rate was 64.10%. According to the patient’s own assessment, improvements in patient-centered parameters were experienced in the quality of sleep (28/35), frequency of apneic episodes at night (28/30), improvement in snoring (30/40), daytime sleepiness (30/38), and tiredness (31/38). Better control of comorbidities like DM and hypertension was experienced by fifteen patients (15/30) Figs. 1 and 2.
Fig. 1.
BPP
Fig. 2.
Endoscopic midline glossectomy
Discussion
Adult OSA surgery includes an array of operative procedures to widen or stabilize different levels of the upper airway. Although uvulopalatopharyngoplasty (UPPP) was one of the most popular surgeries, its results were not satisfactory in the long term, leading to modifications and newer procedures. One of the reasons for the poor outcome following UPPP was because it failed to address multilevel obstruction [11], particularly the tongue base. A better understanding of the complexity of upper airway collapse has led to multilevel surgery that can be tailor-made according to the sites and pattern of collapse, thus maximizing the outcome. Awake fiber-optic nasopharyngo-laryngeal endoscopic evaluation and DISE have been performed in all patients in the current study, and a surgical plan was made accordingly. Similar to previous authors, we found DISE superior to awake endoscopy in this context since it was more sensitive in demonstrating additional areas of upper airway collapse [11–13].
Evaluation of the upper airway in previous studies has shown that the velum and tongue base have a greater tendency to collapse during sleep (3, 11, 13). In our study, 42.5% of patients had Freedman tongue position grades 3 and 4, contributing to the severity of retropalatal obstruction as well. Further, Chen Zhao et al. [15] have described a higher tongue base contributing to velopharyngeal obstruction. Numerous studies have advocated multi-level surgery involving the soft palate and the base of the tongue as being safe and successful in a well-selected group [16, 17]. Vicini et al. applied robotic tongue-base surgery combined with ESP to treat OSA patients and reported a higher surgical success rate [18]. Besides, various palatal surgeries that are combined with TORS produce a higher surgical success rate, as found by Cammaroto et al. [19]. In the present era of upper airway stimulation (UAS) surgery, there is still a place for palato-pharyngeal and base-of-tongue procedures since UAS is limited by candidature criteria, variable anatomy, and the non-availability of the procedure in several countries.
Barbed palatopharyngoplasty [5] was undertaken in all patients to relieve the velum and lateral oropharyneal wall collapse. Several modifications of the lateral pharyngoplasty technique have emerged since Cahali described it in 2010 [20]. The barbed suturing technique introduced by Mantiowani et al. and later modified by Vicini et al. in barbed reposition pharyngoplasty (BRP) has further improved the ease of the procedure and its results. BPP has the same benefits as a BRP combined with an anterior palatoplasty procedure. It is a functional, minimally invasive procedure that was done on all patients in this study group. In severe cases of OSA, the diminished upper airway dilating effect of the palatopharyngeus muscle becomes a significant factor contributing to the lateral collapse [21]. Considering this fact, in the lateral pharyngoplasty part, we have taken measures to expose and include the maximum length of palatopharyngeus that can be reached through the oropharynx. Using multiple loops of barbed sutures around palatopharyngeus muscle and by using pterygo-mandibular raphy as an anchoring point, we ensured stiffening and effective superiolateral repositioning of the lateral pharyngeal wall. Antero-posterior widening achieved by BPP is greater than in previous techniques like BRP since it includes an anterior palatoplasty as well. This has resulted in the opening up of the velum in all three directions. It has been our observation that often varying degrees of anteroposterior and lateral patterns of collapse of the velum can coexist in a single patient, and we require a procedure like BPP for its correction. Although complete concentric collapse (CCC) of the palate has been associated with a less favorable outcome following palatopharyngeal surgery in previous studies, we experienced comparable results in all types of palatal collapse following BPP [22, 23]. Since it is effective even in concentric types of palatal collapse, we feel it is well suited as part of a multilevel surgery Tables 1, 2, 3 and 4.
Table 1.
Baseline characteristics
| Frequency (n = 40) | Percentage (%) | |
|---|---|---|
| Age Group (years) | ||
| ≤ 40 | 25 | 62.5 |
| > 40 | 15 | 37.5 |
| Mean | 43.15 ± 10.55 | |
| Gender | ||
| Male | 26 | 65 |
| Female | 14 | 35 |
| BMI (Kg/m 2 ) | ||
| Overweight (23-24.9) | 3 | 7.5 |
| Obese (≥ 25) | 37 | 92.5 |
| Mean | 31.5 ± 6.89 | |
| Neck circumference (cm) | ||
| < 40 | 17 | 42.5 |
| ≥ 40 | 23 | 57.5 |
| Tonsil size | ||
| Grade 1 & 2 | 21 | 52.5 |
| Grade 2 & 3 | 19 | 47.5 |
| Retropalatal obstruction | ||
| Partial | 4 | 10 |
| Complete | 36 | 90 |
| Retroglossal Obstruction | ||
| Partial | 7 | 17.5 |
| Complete | 33 | 82.5 |
| Freedman tongue position | ||
| FTP 1 & 2 | 23 | 57.5 |
| FTP 3 & 4 | 17 | 42.5 |
| VAS | 40 | |
| > 5 | 36 | 90 |
| ≤ 5 | 4 | 10 |
| ESS | ||
| 0 | 2 | 5 |
| < 10 | 5 | 12.5 |
| ≥ 10 | 33 | 82.5 |
| AHI | ||
| Moderate (15–30) | 18 | 45 |
| Severe (> 30) | 22 | 55 |
Table 2.
Post-operative Complications
| Complications | Frequency (n = 40) | Percentage |
|---|---|---|
| Early (within first week) | ||
| Pain | 38 | 95 |
| Dysphagia | 35 | 87.5 |
| Velopharyngeal insufficiency | 0 | 0 |
| Bleeding | 5 | 12.5 |
| Aspiration | 0 | 0 |
| Breathing difficulty | 1 | 2.5 |
| Severe Tongue edema | 3 | 7.5 |
| Late (2nd to 6th week) | ||
| Foreign body sensation | 3 | 7.5 |
| Pain | 2 | 5 |
| Extrusion of sutures | 10 | 25 |
| Loss of taste | 1 | 2.5 |
| Palatal granuloma | 2 | 5 |
Table 3.
Sleep Parameters
| Parameters | Pre-operative | Post-operative | P value |
|---|---|---|---|
| VAS | 7.27 ± 1.94 | 2.32 ± 1.20 | < 0.0001 |
| ESS | 14.20 ± 4.81 | 4.17 ± 2.87 | < 0.0001 |
| AHI | 40.74 ± 36.57 | 16.49 ± 13.14 | < 0.0001 |
| L-Sat | 74.21 ± 10.48 | 86.1 ± 8.80 | < 0.0001 |
Table 4.
Quality of life improvement
| Parameters | Post–operative Improvement Frequency / number | Percentage (%) |
|---|---|---|
| Snoring | 30/40 | 75 |
| Daytime somnolence | 30/38 | 78.95 |
| Daytime tiredness | 31/38 | 81.58 |
| Quality of sleep | 28/35 | 80 |
| Apnoeic episodes during sleep | 28/30 | 93.33 |
| Control of comorbidities | 15/30 | 50 |
Clinical evaluation of the Friedman tongue position provides an indication of the degree of tongue base obstruction and posterior airway space [24]. Lingual tonsil hypertrophy also needs to be assessed by awake flexible nasopharyngoscopy, which contributes to the hypopharyngeal collapse. Volumetric reduction surgery is the treatment of choice for tongue base obstruction due to soft tissue hypertrophy. Surgical procedures to deal with tongue base obstruction are limited and technically challenging. Transoral Robotic Surgery (TORS), coblator-assisted endoscopic midline glossectomy, or lymphoid tissue excision are the definitive procedures for volume reduction. Coblator-assisted excision has certain advantages: the device is easy to handle, can be adjusted to the shape of the tongue, and can reach difficult-to-access regions of the tongue. The collateral damage to the tissues is also minimized, as it generates a lower temperature [25] and is more economical than TORS with comparable surgical outcomes [25–27].
Preoperatively, retropalatal obstruction was complete in 90% of subjects and complete retroglossal obstruction in 82.5%. Post-operative awake nasopharyngoscopy revealed a reduction in velopharyngeal and retroglossal collapse. Sleep parameters like AHI, lowest oxygen saturation, and VAS score for snoring significantly improved after surgery. The overall success rate was 62.5%, according to Sher criteria. Similar to previous studies [28], we also found that higher Friedman stages had lower success rates when Sher’s criteria were applied. In single-stage multilevel surgery, the final results reflect the multilevel benefit of all the procedures [14]. In this study, postoperative results also represent the synergistic effect of both surgeries.
The efficacy of OSA treatment is currently judged based on polysomnographic results alone. The ultimate success of treatment depends on the relief of debilitating symptoms and the control of resultant metabolic disturbances. At times, patients’ reports of improvement following surgical treatment were found to be discordant with PSG results. Since success according to Sher criteria is based on AHI values alone, it may not reflect the improvement in other patient-centered parameters following surgery [29, 30]. Patients in this study group have reported a reduction in snoring, daytime somnolence, less tiredness with better performance at work, better quality of sleep, absence of apneic episodes at night, reduction in weight, and better control of comorbidities like hypertension and diabetes mellitus.
Conclusion
Multilevel surgery with barbed palatopharyngoplasty combined with coblator-assisted midlie glossectomy is effective in reducing disease severity in moderate-to-severe OSAS cases. The efficacy of combined surgical treatment was evidenced by improvements in PSG results and patient-centered quality of life parameters.
Author Contributions
Susan K Sebastian. The conception of the work, the acquisition, analysis, interpretation, critical analysis of data and drafting. Approved the version to be published and agreed to be accountable for all aspects of the work. Gautam Arora. Analysis, interpretation and drafting of data Approved the version to be published and agreed to be accountable for all aspects of the work. Anand Kumar. C. Acquisition and analysis of data. Approved the version to be published and agreed to be accountable for all aspects of the work. Amrita Grace Noah. Acquisition and analysis of data. Approved the version to be published and agreed to be accountable for all aspects of the work.
Funding
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sector.
Declarations
Institutional Ethics Committee Clearence Obtained Number
SSHEC/R0127.
Competing Interests
The authors declare no competing interest.
Footnotes
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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