Obstructive sleep apnea (OSA) is a chronic sleep-related breathing disorder characterized by recurrent episodes of complete or partial upper airway obstruction during sleep, resulting in intermittent hypoxia, sleep fragmentation, and excessive daytime sleepiness. It has emerged as a major public health concern because of its increasing prevalence and its strong association with cardiovascular disease, cerebrovascular accidents, metabolic syndrome, diabetes mellitus, cognitive impairment, and reduced quality of life. The rising prevalence of obesity, sedentary lifestyle, and aging population have contributed significantly to the increasing burden of OSA worldwide. Polysomnography (PSG) remains the gold standard for diagnosing OSA and determining disease severity through the Apnea-Hypopnea Index (AHI). Clinical assessment is supplemented by validated screening tools such as the Epworth Sleepiness Scale (ESS), Friedman tongue position, modified Mallampati score, and Drug-Induced Sleep Endoscopy (DISE). Among these, DISE has gained considerable importance because it allows dynamic visualization of upper airway collapse during pharmacologically induced sleep, enabling accurate localization of the obstructive site and facilitating individualized surgical planning. Continuous Positive Airway Pressure (CPAP) is considered the first-line treatment for moderate and severe OSA. Despite its excellent efficacy in eliminating airway obstruction, long-term compliance remains poor because of discomfort, claustrophobia, facial irritation, nasal dryness, air leakage, and sleep disturbance. Consequently, surgical treatment has become an important therapeutic option for carefully selected patients, particularly those with well-defined anatomical obstruction who are unable to tolerate CPAP therapy. The retropalatal region is the most frequent site of upper airway collapse in patients with OSA. Traditional procedures such as uvulopalatopharyngoplasty (UPPP) enlarge the retropalatal airway by excising portions of the uvula and soft palate. Although effective in selected patients, these procedures may lead to complications including persistent foreign body sensation, dysphagia, altered speech, velopharyngeal insufficiency, nasal regurgitation, chronic throat irritation, and impaired swallowing due to disruption of normal palatal anatomy. To overcome these limitations, several uvula-sparing palatal procedures have been developed, including 1. Expansion Sphincter Pharyngoplasty (ESP), 2.Anterior Palatoplasty (AP), 3.Barbed Expansion Pharyngoplasty (BEP), and 4.Lateral Pharyngoplasty. These procedures aim to enlarge and stabilize the retropalatal airway while preserving the uvula and levator veli palatini muscle, thereby maintaining normal velopharyngeal function. Preservation of the uvula is believed to reduce postoperative morbidity without compromising surgical efficacy. Recent studies have reported encouraging improvements in objective polysomnographic parameters and subjective quality-of-life outcomes following these procedures. Although uvula-sparing techniques are increasingly adopted worldwide, evidence from the Indian population remains limited. Variations in craniofacial anatomy, body mass index, and disease characteristics may influence surgical outcomes, making local evidence essential. Furthermore, comparative evaluation using both objective measures such as polysomnography and subjective assessment tools remains scarce. The present quasi-experimental study was therefore undertaken to evaluate the effectiveness of uvula-sparing palatal surgeries in patients with isolated palatal obstruction diagnosed using DISE. Surgical outcomes were assessed by comparing preoperative and postoperative Apnea-Hypopnea Index, oxygen saturation, arousal index, modified Mallampati score, and Epworth Sleepiness Scale. In addition, postoperative symptoms related to preservation of the uvula were evaluated to determine whether these techniques provide effective airway improvement while minimizing complications and improving patients’ quality of life.

Study Design and Setting A prospective quasi-experimental before-and-after study was conducted in the Upgraded Institute of Otorhinolaryngology, Rajiv Gandhi Government General Hospital, Madras Medical College, Chennai, between February 2024 and January 2025 after obtaining approval from the Institutional Ethics Committee. The study evaluated the effectiveness of uvula-sparing palatal surgeries in patients with obstructive sleep apnea (OSA) having isolated palatal obstruction. Study Population Adult patients presenting to the snoring clinic in ENT department with complaints suggestive of OSA, including habitual snoring, witnessed apneic episodes, excessive daytime sleepiness, and mouth breathing, were screened for eligibility. Thirty-one consecutive patients fulfilling the inclusion criteria were enrolled after obtaining written informed consent. Inclusion Criteria Patients were included if they fulfilled all of the following criteria: • Age between 18 and 60 years • Either sex • Body Mass Index (BMI) <40 kg/m² • Polysomnographically confirmed OSA • Single-level palatal obstruction demonstrated on Drug-Induced Sleep Endoscopy (DISE) • Willingness to undergo surgery and comply with postoperative follow-up. Exclusion Criteria Patients were excluded if they had: • Age <18 years or >60 years • BMI ≥40 kg/m² • Craniofacial abnormalities • Neuromuscular disorders • Multilevel upper airway obstruction • Contraindications to surgery or inability to complete follow-up. Preoperative Evaluation All patients underwent a standardized clinical evaluation that included detailed history taking and comprehensive ENT examination. Subjective daytime sleepiness was assessed using the Epworth Sleepiness Scale (ESS), while upper airway anatomy was evaluated using the Modified Mallampati Score (MMS) and Friedman staging. Every patient underwent overnight Type I polysomnography (PSG) to determine: • Apnea-Hypopnea Index (AHI) • Lowest oxygen saturation (SpO₂ nadir) • Arousal Index • Sleep architecture Drug-Induced Sleep Endoscopy (DISE) was subsequently performed under sedation to identify the precise level and pattern of upper airway collapse. The VOTE classification was used to characterize obstruction, and only patients with isolated palatal collapse were considered suitable for surgery. Surgical Intervention The choice of uvula-sparing procedure was individualized according to the anatomical pattern of obstruction identified during DISE. The procedures performed included: • Expansion Sphincter Pharyngoplasty (ESP) • Anterior Palatoplasty (AP) • Barbed Wire Expansion Pharyngoplasty (BWEP) • Lateral pharyngoplasty. All procedures aimed to enlarge the retropalatal airway while preserving the uvula and maintaining the integrity of the levator veli palatini muscle, thereby minimizing postoperative velopharyngeal dysfunction and swallowing disturbances.airway monitoring, were followed in all patients. Standard perioperative protocols, including antibiotic prophylaxis, analgesia, and postoperative Follow-up Assessment Patients were reviewed at 3 months and 6 months following surgery. At each follow-up visit, patients underwent: • Clinical examination • Epworth Sleepiness Scale assessment • Modified Mallampati scoring Repeat overnight polysomnography was performed to reassess: • Apnea-Hypopnea Index • Lowest oxygen saturation • Arousal Index Patients were also evaluated for postoperative symptoms including: • Foreign body sensation • Persistent throat clearing • Pharyngeal irritation • Nasal regurgitation • Speech disturbances These parameters were assessed to determine whether preservation of the uvula translated into improved postoperative functional outcomes. Outcome Measures The primary outcome was surgical success as determined by objective improvement in polysomnographic parameters, particularly reduction in Apnea-Hypopnea Index. Successful surgery was defined as a reduction of at least 50% in postoperative AHI compared with baseline. Secondary outcomes included • Improvement in Epworth Sleepiness Scale score • Improvement in Modified Mallampati Score • Increase in lowest nocturnal oxygen saturation • Reduction in arousal index • Improvement in patient-reported quality of life • Reduction in postoperative palatal symptoms. Statistical Analysis Data were entered into a computerized database and analyzed using appropriate statistical software. Continuous variables were expressed as mean ± standard deviation, whereas categorical variables were summarized as frequencies and percentages. Preoperative and postoperative variables were compared using repeated-measures statistical methods. Multivariate Analysis of Variance (MANOVA) was employed to evaluate changes in objective and subjective outcome measures following surgery. A p-value of <0.05 was considered statistically significant.

A total of 31 patients with polysomnography-confirmed obstructive sleep apnea and isolated palatal obstruction completed the study. All patients underwent uvula-sparing palatal surgery and completed the scheduled postoperative follow-up with repeat clinical and polysomnographic evaluation. Baseline Characteristics The study population consisted of 24 males (77.4%) and 7 females (22.6%), indicating a marked male predominance. The age distribution was nearly equal, with 15 patients (48.4%) aged 18–35 years and 16 patients (51.6%) aged over 35 years. All participants had a body mass index below 40 kg/m² in accordance with the study eligibility criteria. Table 1: Distribution of study patients by age group Age Frequency (n) Percentage (%) 18–35 years 15 48.4 36 and above 16 51.6 Total 31 100 Table 2: Distribution of study patients by gender Gender Frequency (n) Percentage (%) Female 7 22.58% Male 24 77.42% Total 31 100% Drug-induced sleep endoscopy confirmed isolated palatal obstruction in all cases. Depending on the pattern of airway collapse, patients underwent Expansion Sphincter Pharyngoplasty (ESP), Anterior Palatoplasty (AP), or Barbed Wire Expansion Pharyngoplasty (BWEP). Surgical selection was individualized based on DISE findings. Epworth Sleepiness Scale A significant improvement in subjective daytime sleepiness was observed following surgery. Most patients demonstrated a marked reduction in Epworth Sleepiness Scale scores at postoperative follow-up, reflecting improved daytime alertness and sleep quality. The greatest improvement was observed among patients undergoing Expansion Sphincter Pharyngoplasty and Anterior Palatoplasty. Overall, postoperative ESS scores indicated clinically meaningful symptomatic improvement across all surgical groups. Table 3: Distribution of study patients by Epworth Sleepiness Scale on each group Surgery Frequency (n) Epworth Sleepiness Scale Pre-Intervention Mean and Standard Deviation Epworth Sleepiness Scale Post-Intervention Mean and Standard Deviation P value Anterior Palatoplasty 10 16.1 ± 5.76 6.9 ± 3.78 Barbed Wire Expansion Pharyngoplasty 11 16 ± 3.19 9.18 ± 3.48 0.15 Expansion Sphincter Pharyngoplasty 10 14.8 ± 4.15 6.8 ± 2.57 Total 31 15.65 ± 4.34 7.67 ± 3.40 Apnea–Hypopnea Index Objective assessment by overnight polysomnography demonstrated a substantial reduction in disease severity following surgery. The mean Apnea–Hypopnea Index decreased from 42.50 ± 19.38 events/hour preoperatively to 19.77 ± 12.02 events/hour postoperatively, representing a statistically significant improvement (p = 0.02). Using the accepted definition of surgical success (≥50% reduction in AHI), 75.8% of patients achieved successful treatment outcomes, while the remaining patients also demonstrated symptomatic improvement despite not fulfilling the objective success criterion. Among the various procedures, Barbed Wire Expansion Pharyngoplasty produced the greatest reduction in AHI, followed closely by Expansion Sphincter Pharyngoplasty. Table 4: Distribution of study patients by Apnoea-Hypopnea Index on each group Surgery Frequency (n) Apnoea-Hypopnea Index Pre-Intervention Apnoea-Hypopnea Index Post-Intervention P value Mean and Standard Deviation Mean and Standard Deviation Anterior Palatoplasty 10 27.69 ± 11.82 16.03 ± 13.13 Barbed Wire Expansion Pharyngoplasty 11 55.87 ± 17.76 25.99 ± 10.12 0.02 Expansion Sphincter Pharyngoplasty 10 42.61 ± 17.32 16.67 ± 11.05 Total 31 42.50 ± 19.38 19.77 ± 12.02 Oxygen Saturation Improvement in nocturnal oxygenation was observed following surgery. The mean lowest oxygen saturation increased from 74.87 ± 9.09% before Table 5: Distribution of study patients by Lowest Saturation on each group Surgery Frequency Lowest Saturation Pre-Intervention Lowest Saturation Post-Intervention P value Mean and Standard Deviation Mean and Standard Deviation Anterior Palatoplasty 10 80.2 ± 8.85 91.5 ± 3.56 Barbed Wire Expansion Pharyngoplasty 11 70.90 ± 8.99 86.09 ± 6.09 0.342 Expansion Sphincter Pharyngoplasty 10 73.9 ± 7.46 88.9 ± 3.66 Total 31 74.87 ± 9.09 88.74 ± 5.03 surgery to 88.74 ± 5.03% after surgery, indicating improved upper airway patency during sleep. Although statistical significance was not demonstrated for this parameter, the improvement was considered clinically meaningful because better nocturnal oxygenation is associated with reduced cardiovascular stress and improved sleep physiology. Patients undergoing ESP and AP demonstrated the greatest postoperative improvement in oxygen saturation. Arousal Index Postoperative polysomnography demonstrated a reduction in sleep fragmentation. The mean arousal index decreased from 34.68 ± 12.44 to 19.58 ± 9.65, indicating fewer respiratory-related arousals and improved sleep continuity. This improvement correlated well with the reduction in daytime sleepiness reported by patients during follow-up. Table 6: Distribution of study patients by Arousal Index on each group Surgery Frequency (n) Arousal Index Pre-Intervention Arousal Index Post-Intervention P value Mean and Standard Deviation Mean and Standard Deviation Anterior Palatoplasty 10 36.95 ± 13.61 23.66 ± 12.35 Barbed Wire Expansion Pharyngoplasty 11 37.93 ± 12.56 18.9 ± 7.27 0.258 Expansion Sphincter Pharyngoplasty 10 28.84 ± 9.94 16.24 ± 8.23 Total 31 34.68 ± 12.44 19.58 ± 9.65 Modified Mallampati Score Anatomical improvement of the retropalatal airway was evident on postoperative examination. Before surgery, all patients were classified as Modified Mallampati Class III or IV. Following surgery, Class IV airway grades were eliminated, and Class II became the predominant postoperative finding, accounting for approximately 74% of patients. These findings indicate successful widening of the retropalatal airway following uvula-sparing surgery. Table 7: Distribution of study patients by Modified Mallampati scoring on each group SURGERY Modified Mallampati Score PRE OP Modified Mallampati Score POST OP Class 1 2 3 4 1 2 3 4 Frequency (n) and Percentage (%) Anterior Palatoplasty 0 (0%) 0 (0%) 6 (19.4%) 4 (12.9%) 0 (0%) 6 (19.4%) 4 (12.9%) 0 (0%) Barbed Wire Expansion Pharyngoplasty 0 (0%) 0 (0%) 1 (3.2%) 10 (32.3%) 0 (0%) 10 (32.3%) 1 (3.2%) 0 (0%) Expansion Sphincter Pharyngoplasty 0 (0%) 0 (0%) 2 (6.5%) 8 (25.8%) 0 (0%) 7 (22.6%) 3 (9.7%) 0 (0%) Total 0(0%) 0(0%) 9(29%) 22(71%) 0(0%) 23(74.2%) 8(25.8%) 0(0%) Quality of Life All three surgical techniques resulted in improvement in disease-related quality of life. Patients reported: • Reduced excessive daytime sleepiness • Better nocturnal sleep quality • Decreased snoring intensity • Improved overall daily functioning • Better social interaction and partner satisfaction The subjective improvement closely paralleled objective improvements demonstrated by polysomnography. Table 8: Distribution of study patients by Level of Obstruction Level of Obstruction Frequency (n) Percentage (%) Oropharynx 10 32.3 Velum 21 67.7 Total 31 100 Table 9: Distribution of study patients by Direction of Obstruction Direction of Obstruction Frequency (n) Percentage (%) Anteroposterior 10 32.3 Circumferential 11 35.5 Lateral Wall 10 32.3 Total 31 100 Table 10: Distribution of study patients based on Surgery undertaken Surgery Frequency (n) Percentage (%) Anterior Palatoplasty 10 32.3 Barbed Wire Expansion Pharyngoplasty 11 35.5 Expansion Sphincter Pharyngoplasty 10 32.3 Total 31 100 Postoperative Morbidity Peservation of the uvula was associated with minimal postoperative complications. Most patients did not experience persistent: • Foreign body sensation • Nasal regurgitation • Hypernasal speech • Constant throat clearing • Chronic pharyngeal irritation No major postoperative complications requiring re-intervention were reported during the follow-up period. These findings suggest that uvula-sparing procedures preserve normal palatal function while effectively enlarging the upper airway. Overall Surgical Outcome Overall, uvula-sparing palatal surgery resulted in significant improvement in both subjective and objective indicators of obstructive sleep apnea. The procedures produced: • Significant reduction in Apnea–Hypopnea Index • Improved Epworth Sleepiness Scale scores • Improved nocturnal oxygen saturation • Reduced arousal index • Better Modified Mallampati grading • Improved quality of life with minimal postoperative morbidity Collectively, these findings support uvula-sparing palatal surgery as an effective treatment option for carefully selected patients with isolated retropalatal obstruction. EXPANSION SPHINCTER PHARYNGOPLASTY: STEP 1: Bilateral tonsillectomy STEP 2: Exposure of the palatopharyngeus (vertical Fibers) STEP 3: Elevation of the palatoohayngeus

Obstructive sleep apnea (OSA) is a multifactorial disorder characterized by recurrent upper airway collapse during sleep, leading to intermittent hypoxia, sleep fragmentation, and significant cardiovascular, metabolic, and neurocognitive morbidity. While Continuous Positive Airway Pressure (CPAP) remains the standard treatment for moderate and severe OSA, long-term adherence remains suboptimal because of discomfort, claustrophobia, mask-related complications, and lifestyle inconvenience. Consequently, surgical management has become an increasingly important treatment option in carefully selected patients with anatomically correctable upper airway obstruction. The present study evaluated the efficacy of uvula-sparing palatal surgeries in patients with isolated retropalatal obstruction confirmed by Drug-Induced Sleep Endoscopy (DISE), demonstrating significant improvements in both objective polysomnographic parameters and subjective clinical outcomes. Demographic Characteristics The majority of patients in the present study were male (77.4%), with nearly equal representation of younger and older adults. This male predominance is consistent with the epidemiology of OSA reported worldwide. Anatomical differences in upper airway structure, patterns of fat deposition around the pharynx, and hormonal influences are believed to contribute to the higher prevalence of OSA among men. Similarly, obesity remains one of the strongest risk factors for OSA, although patients with morbid obesity were excluded from the present study to minimize confounding factors related to multilevel airway collapse. Importance of DISE-Guided Patient Selection One of the major strengths of the present study is the use of Drug-Induced Sleep Endoscopy for preoperative assessment. Unlike awake examination or Müller’s manoeuvre, DISE allows dynamic visualization of upper airway collapse under sleep-like conditions, thereby accurately identifying the anatomical level and pattern of obstruction. Only patients with isolated palatal obstruction were included, enabling selection of the most appropriate uvula-sparing surgical procedure. Careful patient selection probably contributed substantially to the favorable outcomes observed in this study. Recent studies by Kezirian et al. and Vicini et al. have emphasized that DISE improves surgical planning by tailoring treatment to the individual pattern of airway collapse, thereby improving postoperative success rates. The findings of the present study further support the incorporation of DISE into routine preoperative evaluation for patients undergoing sleep surgery. Improvement in Daytime Sleepiness Excessive daytime sleepiness is one of the most disabling symptoms of OSA and significantly affects work performance, cognitive function, and quality of life. In the present study, postoperative Epworth Sleepiness Scale scores improved considerably across all surgical groups, indicating restoration of more physiological sleep architecture. These findings are comparable with those reported by Mohan Kumar et al., who demonstrated a marked reduction in ESS following uvula-sparing palatal surgery. Similar improvements have also been described after Expansion Sphincter Pharyngoplasty and Barbed Pharyngoplasty in several international studies. Although subjective assessment may be influenced by patient perception, the consistent improvement observed alongside objective polysomnographic parameters strongly supports the effectiveness of these procedures. Reduction in Apnea–Hypopnea Index The Apnea–Hypopnea Index remains the principal objective measure of treatment efficacy in OSA. In the present study, mean AHI decreased significantly from 42.50 ± 19.38 events/hour preoperatively to 19.77 ± 12.02 events/hour postoperatively, representing a clinically meaningful reduction in disease severity. Furthermore, nearly three-fourths of patients achieved the accepted definition of surgical success, namely a reduction of at least 50% in postoperative AHI. These findings are comparable with those reported by Pang et al., who demonstrated excellent outcomes following Expansion Sphincter Pharyngoplasty in patients with lateral pharyngeal wall collapse. Likewise, Vicini et al. and Montevecchi et al. reported significant postoperative reductions in AHI following modern reconstructive palatal procedures. The present study therefore reinforces the growing evidence that uvula-sparing techniques provide effective treatment while preserving normal palatal function. Oxygen Saturation and Sleep Quality Improvement in nocturnal oxygen saturation represents another clinically important outcome. Intermittent hypoxemia contributes to sympathetic activation, endothelial dysfunction, hypertension, cardiac arrhythmias, and metabolic disturbances in patients with OSA. Following surgery, the mean lowest oxygen saturation increased substantially. Although statistical significance was not demonstrated, the magnitude of improvement is clinically relevant because even modest reductions in nocturnal hypoxemia may reduce long-term cardiovascular risk. Similar observations have been reported by Lorusso et al., who found that Expansion Sphincter Pharyngoplasty significantly improved nocturnal oxygenation while maintaining favorable postoperative functional outcomes. Improvement in Arousal Index Repeated respiratory events during sleep produce frequent cortical arousals that disrupt normal sleep architecture and prevent restorative sleep. The significant reduction in arousal index observed after surgery suggests improved sleep continuity and fewer sleep interruptions. Reduction in arousal frequency likely explains the marked postoperative improvement in daytime alertness and quality of life observed in the present study. Restoration of consolidated sleep has been associated with improved cognitive performance, memory, mood, and metabolic regulation, emphasizing that successful surgical treatment extends beyond simple reduction of snoring or apnea frequency. Anatomical Improvement Postoperative improvement in Modified Mallampati Score reflected enlargement and stabilization of the retropalatal airway. Elimination of Class IV airways and predominance of Class II findings indicate successful anatomical reconstruction without sacrificing the uvula. Previous imaging studies by Schwab et al. have demonstrated that enlargement of the retropalatal airway correlates well with improved airflow during sleep. The present study provides further clinical evidence that reconstructive rather than ablative palatal surgery can effectively restore upper airway patency. Advantages of Uvula-Sparing Procedures Traditional uvulopalatopharyngoplasty achieves airway enlargement primarily by tissue excision, which may result in complications such as velopharyngeal insufficiency, hypernasal speech, dysphagia, persistent foreign body sensation, and chronic throat irritation. In contrast, uvula-sparing techniques preserve the normal anatomy of the soft palate while repositioning pharyngeal muscles to enlarge the airway. In the present study, postoperative morbidity was minimal. Most patients did not experience persistent throat discomfort, nasal regurgitation, or speech disturbances. Preservation of the uvula likely contributed to maintenance of normal swallowing and palatal function. These findings agree with previous studies by Babademez et al., Pang et al., and Montevecchi et al., all of whom reported excellent functional outcomes with reconstructive palatal procedures. Clinical Implications The present study highlights several important clinical implications. First, careful patient selection using DISE enables identification of patients most likely to benefit from isolated palatal surgery. Second, modern uvula-sparing procedures provide meaningful improvement in both objective sleep parameters and patient-reported outcomes. Third, preservation of normal palatal anatomy reduces postoperative complications traditionally associated with ablative surgery. These findings support the growing trend toward functional reconstruction rather than tissue resection in contemporary sleep surgery. Strengths of the Study The present study has several strengths. All patients underwent standardized preoperative assessment using polysomnography and DISE, ensuring accurate diagnosis and localization of obstruction. Objective postoperative evaluation was performed using repeat polysomnography in addition to validated clinical scoring systems. Furthermore, all procedures were carried out within a single tertiary referral center using standardized surgical protocols, reducing variability in patient management. Limitations Certain limitations should be acknowledged. The sample size was relatively small and derived from a single institution, which may limit the generalizability of the findings. The absence of a comparison group undergoing CPAP therapy or conventional uvulopalatopharyngoplasty precludes direct comparison between treatment modalities. In addition, the follow-up period was relatively short and therefore does not provide information regarding long-term durability of surgical outcomes. Future multicenter randomized studies with larger patient populations and longer follow-up are required to confirm these findings and determine long-term efficacy. SUMMARY The present study demonstrates that uvula-sparing palatal surgery provides significant improvement in both objective polysomnographic parameters and subjective quality-of-life measures in carefully selected patients with isolated palatal OSA. The combination of DISE-guided surgical planning and reconstructive palatal techniques offers effective airway enlargement while preserving normal palatal function and minimizing postoperative morbidity. These findings support the expanding role of uvula-sparing surgery as an important component of individualized management for obstructive sleep apnea.

Uvula-sparing palatal surgery is an effective surgical option for carefully selected patients with obstructive sleep apnea and isolated retropalatal obstruction. In the present study, these procedures resulted in significant improvement in both objective polysomnographic parameters, including the Apnea-Hypopnea Index, lowest oxygen saturation, arousal index, and Modified Mallampati score, as well as subjective outcomes measured by the Epworth Sleepiness Scale and quality of life. Preservation of the uvula maintained normal palatal function while minimizing postoperative complications such as foreign body sensation, throat irritation, nasal regurgitation, and speech disturbances. The use of Drug-Induced Sleep Endoscopy enabled accurate identification of the site of obstruction and appropriate selection of the surgical technique, thereby contributing to favorable outcomes. Although further multicenter studies with larger sample sizes and longer follow-up are warranted, the present findings support uvula-sparing palatal surgery as a safe, effective, and function-preserving treatment modality for selected patients with obstructive sleep apnea.

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