A Randomized Trial of Laser-assisted Uvulopalatoplasty in the Treatment of Mild Obstructive Sleep Apnea

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1 A Randomized Trial of Laser-assisted Uvulopalatoplasty in the Treatment of Mild Obstructive Sleep Apnea Kathleen A. Ferguson, Kim Heighway, and Ralph R. F. Ruby Departments of Medicine and Otolaryngology, University of Western Ontario, London, Ontario, Canada Laser-assisted uvulopalatoplasty (LAUP) is an outpatient surgical able (6). Many clinicians and patients are convinced of its treatment for snoring and obstructive sleep apnea (OSA), but to effectiveness in relieving snoring based on their personal date, no controlled trials have been published. Forty-five subjects experience, but rarely is treatment success objectively docuwith mild OSA (apnea/hypopnea index [AHI], per hour) were mented. A published guideline focused on the lack of conrandomized to LAUP or to no treatment (control group). The AHI trolled studies and recommended that patients should be told post-laup was reduced by 21% overall and to 10 or less per hour that the risks, benefits, and complications of the procedure in 5 of 21 subjects (24%). Four of 24 subjects in the control group are not known (7). In an update published in 2000, the au- (16.7%) had an AHI of 10 or less per hour at outcome. The AHI thors stated that no controlled trials were found in the peerdecreased with the LAUP compared with no change with the control reviewed literature, and they recommended that LAUP not group at outcome. Ten subjects (48%) reported significantly imbe done for the treatment of OSA (8). However, it could be proved snoring after the LAUP. There was no improvement in excesused for the treatment of snoring. In general, the studies sive daytime sleepiness, but there was a small improvement in qualpublished to date have been retrospective case series or proity of life (unless side effects were included in the quality of life score). Side effects were common, but serious complications did spective precomparisons and postcomparisons without con- not occur. LAUP surgery is effective in some subjects with mild OSA trol groups and often with incomplete follow-up. Problems for the treatment of snoring, but the reduction in AHI and the level with many of these studies include poorly detailed methods of symptomatic improvement were minor overall. and selection criteria, inadequate overnight monitoring (be- fore and after surgery), mainly subjective follow-up, and in- Keywords: obstructive sleep apnea; randomized trial; laser surgery; completely defined outcome criteria. Other deficiencies of laser-assisted uvulopalatoplasty this literature have been well described previously (9). The objective of this study was to determine with a ran- There are a number of options for the treatment of snoring domized, controlled trial the efficacy of LAUP in relieving and obstructive sleep apnea (OSA). Patients with moderate OSA in patients with mild symptomatic sleep apnea. The to severe OSA are usually treated with nasal continuous secondary objectives were to determine the effect of LAUP positive airway pressure (1). Although continuous positive on symptoms of OSA, including snoring, daytime sleepiness, airway pressure eliminates apnea in virtually all cases, there and quality of life. are problems with patient acceptance of continuous positive airway pressure therapy, particularly in patients with mild OSA. Oral appliances are safe and reasonably effective in METHODS patients with mild OSA, but they also represent a control Forty-five subjects who had mild OSA (apnea/hypopnea index [AHI], and not a cure (2, 3). Patients who desire a cure for their ) and complained of loud snoring were recruited. Weight, body problem generally look to surgical treatment. The two most mass index, blood pressure, and neck circumference were recorded at common surgical procedures are uvulopalatopharyngoplasty baseline. A detailed questionnaire was administered along with the (UPPP) and laser-assisted uvulopalatoplasty (LAUP). Epworth Sleepiness Scale (10) and the Calgary Sleep Apnea Quality of Life Index (SAQLI) (11). The five domains of the SAQLI include Kamami developed the LAUP procedure as an alternative domain A daily functioning, domain B social interactions, domain C to UPPP (4). He first used it in patients who complained of emotional functioning, domain D symptoms, and domain E treatmentsnoring after UPPP and who still had residual vibrating tissue related symptoms (side effects and complications). Snoring intensity on their soft palate (5). Subsequently, the procedure was and frequency were rated on a modified four-point Likert Scale (never, expanded to patients who wanted their snoring treated with- softly, moderately, loudly and never, rarely, sometimes, often respectively). out undergoing a major procedure under general anesthesia. The bed partner or household member rated snoring intensity Despite its widespread use, LAUP has not been established (0 none to 10 loud) and frequency (0 never to 10 always) as an effective therapy for OSA in the setting of controlled with a visual analog scale. clinical trials, and in uncontrolled trials, the results are varieither the LAUP group or the no-treatment group (control group). Using a table of random numbers, subjects were randomized to The control subjects were not offered any therapy but were offered LAUP at the end of the study. Questionnaires, scales, and the polysomnogram were repeated 3 months after the last LAUP procedure or 6 (Received in original form August 10, 2001; accepted in final form August 6, 2002) months after baseline in the control group. The frequency and severity Supported by the Ontario Thoracic Society; the Department of Medicine, Univerrecorded. of treatment side effects and complications in the LAUP group were sity of Western Ontario; and the Department of Otolaryngology, University of Western Ontario, London, Canada. Correspondence and requests for reprints should be addressed to Dr. Kathleen A. Ferguson, London Health Sciences Centre, 375 South Street, London, ON, N6A 4G5, Canada. kafergus@uwo.ca This article has an online supplement, which is accessible from this issue s table of contents online at Am J Respir Crit Care Med Vol 167. pp 15 19, 2003 DOI: /rccm Internet address: Overnight Polysomnography A standard montage was used for polysomnography, including electroencephalogram, electro-oculogram, submental electromyogram, left and right anterior tibialis electromyogram, electrocardiogram, thoracoabdominal motion, oronasal airflow (thermistor), and arterial oxygen saturation with pulse oximetry. Obstructive apneas were defined as the cessation of airflow for at least 10 seconds accompanied by ongoing respiratory effort. Obstructive hypopneas were defined as a reduction

2 16 AMERICAN JOURNAL OF RESPIRATORY AND CRITICAL CARE MEDICINE VOL in airflow of at least 50% for at least 10 seconds accompanied by a group dropped out because of the development of a serious reduction in respiratory effort. Events were associated with an arousal unrelated illness. Data are reported on the remaining 45 subjects and/or an oxygen desaturation of 3% and/or an associated period of (21 LAUP and 24 control subjects), all of whom completed bradycardia/tachycardia. the study and had follow-up polysomnography. The subjects in general were middle aged ( years [31 to 65]), over- LAUP Procedure weight (body mass index, kg/m 2 [23.5 to 43.5]), and The LAUP procedure was repeated at 1- to 2-month intervals. The had complaints of excessive snoring. There were no differences end points for the LAUP procedure were (1) when the snoring was between the LAUP and control groups at baseline with respect to reported to be significantly reduced or eliminated, (2) no more tissue demographic variables or symptoms. One patient in the control could be safely removed, or (3) the patient refused further surgery. Subjects received preoperative pain medication. Topical anesthesia group and one patient in the LAUP group had previously used was applied liberally, and lidocaine was injected into the uvula and soft nasal continuous positive airway pressure without success. No palate. A series of full-thickness vertical trenches were created with patient had previously had palatal surgery. the CO 2 laser on the free edge of the soft palate on either side of the The LAUP subjects had an average of procedures uvula. The uvula was shortened and thinned to a fraction of its former (one to four). The outcome sleep study and final evaluation were size. The edge of the soft palate was also reduced. The tonsils were performed months (3.7 to 14.1) after the baseline study not treated. A backstop on the laser attachment was used to prevent in the control subjects and months (8.2 to 32.2) after injury to the posterior pharyngeal wall. The laser was activated during the baseline study in the LAUP subjects. This was exhalation, and suction was used to remove the smoke from the surgical months (2 to 27.4) after the final laser procedure. field. Subjects received postoperative antibiotics, analgesics, antiinflammatories and dilute hydrogen peroxide gargles for 7 days. Clinical Features and Symptoms Outcome Measurements There was no change in body mass index, neck circumference, or blood pressure during the study in either the LAUP or control The primary outcome measurement was the reduction in AHI in the LAUP group versus the control group. Treatment success was defined groups. The LAUP procedure was effective in reducing snoring as a reduction in AHI to 10 or less per hour. Treatment failure was in some subjects (Tables 1 and 2). Moderate to loud snoring defined as an inadequate reduction in AHI (post-treatment AHI of was still present in 11 subjects (52%) after LAUP and in all the more than 10 per hour). A complete response was defined as a reduction control subjects. Two subjects (10%) reported no more snoring, in AHI to 10 or less per hour along with a satisfactory symptomatic and 8 (38%) reported soft snoring only. There was no change response (as determined by the patient). Subjective outcomes included in the frequency of excessive daytime sleepiness after LAUP snoring frequency and severity, change in symptoms (e.g., excessive (or in the control group), but the patients were only mildly sleepy daytime sleepiness), and quality of life. at baseline. There was no improvement in the frequency of wit- The sample size was calculated with data from published studies of nessed apneas or the presence of unrefreshing sleep after LAUP LAUP (12 16). The study had a 90% power to detect a 25% reduction in AHI in the treatment group compared with no reduction in AHI in and no improvement in the control group (Table 1). the control group with an of The University Of Western Ontario Review Board for Health Sciences Research Involving Human Subjects Quality of Life approved the study. There was no change in quality of life in the control subjects from baseline to outcome. The SAQLI score for domains A, B, Statistical Analysis C, and D increased from to (p 0.003) Continuous variables at baseline and outcome were compared within in the LAUP subjects after treatment. The outcome SAQLI was each group by a paired t test. The changes in the continuous variables measured at the time of the follow-up polysomnogram (in the (e.g., the change in AHI) from baseline to outcome were compared by LAUP subjects, months after the final procedure). an unpaired t test between the groups. Variables that were not normally There were statistically significant increases in the daily functiondistributed (e.g., AHI and visual analog scale for snoring) were coming domain A and social interaction domain B (mean increases pared with nonparametric tests (e.g., Mann-Whitney for unpaired data 0.55, p 0.005, and 0.56, p 0.03, respectively) but no change and Wilcoxon signed-rank test for paired data). Categorical variables were compared between the groups with a chi-squared test. in emotional functioning domain C. The absolute increases in domains A and B are small. There was a significant improvement RESULTS in the symptom domain D with a mean increase of 1.26 (p 0.001) that would be considered a clinically important improvement. Forty-six subjects with mild OSA (AHI, 10.6 to 26.9 per hour) In the control subjects, there was a 0.1 increase in the (data as mean SD [range] unless otherwise specified) were symptom domain D that was less than the increase in the LAUP recruited for this study, including 35 men and 11 women. There group (p 0.04). When side effects or complications of LAUP were 21 subjects randomly assigned to the LAUP group and 25 (domain E) were taken into consideration, the post-laup subjects to the control group. One woman assigned to the control SAQLI score was increased to from baseline a TABLE 1. SYMPTOM RESPONSE IN THE LAUP AND CONTROL GROUP LAUP Group (n 21) Control Group (n 24) % Improved % Unchanged % Improved % Unchanged Moderate to loud snoring* Witnessed apneas Unrefreshing sleep Excessive daytime sleepiness Definition of abbreviation: LAUP laser-assisted uvulopalatoplasty. * Snoring was improved in the LAUP group when compared to the control group (p 0.03) Data are presented as percent of subjects. No significant differences are seen between groups at baseline.

3 Ferguson, Heighway, and Ruby: LAUP in Mild OSA 17 TABLE 2. CLINICAL AND RESPIRATORY VARIABLES BEFORE AND AFTER TREATMENT LAUP Group (n 21) Control Group (n 24) Difference Baseline Difference Baseline Difference Between the Baseline Outcome Minus Outcome Baseline Outcome Minus Outcome Two Groups at Outcome Snoring intensity score p NS p Snoring frequency score p NS p ESS (maximum 24) NS NS NS SAQLI (maximum 7) NS NS NS AHI p NS p 0.04 AHI NREM NS NS p 0.03 AHI REM NS p p Definition of abbreviations: AHI apnea/hypopnea index; ESS Epworth Sleepiness Scale; NREM nonrapid eye movement; REM rapid eye movement; SAQLI sleep apnea quality of life index. Data are presented as mean SD (range). No significant differences are seen between groups at baseline. NS not significant. nonsignificant increase (p 0.09) (Table 2). There was no change Four subjects (19%) reported infections after one of the LAUP in the SAQLI in the control group. procedures, but none sought medical attention. One patient developed diarrhea likely secondary to the prophylactic antibiotic Polysomnographic Variables treatment. Based on our prestudy outcome definitions in the LAUP group, 5 of 21 (24%) were treatment successes (AHI, 10 or less), and Patient Satisfaction 16 of 21 (76%) were treatment failures (AHI, more than 10). The LAUP subjects were asked to rate their level of satisfaction Four of 21 (19%) had a complete response (in terms of AHI with the LAUP treatment. Eleven of 21 (52%) rated themselves and a satisfactory resolution of symptoms). The pretreatment as moderately or very satisfied, and 10 of 21 (48%) rated them- AHI in the LAUP group was per hour, and it de- selves as moderately or very dissatisfied. Although most patients creased to per hour after surgery (p 0.03) (Table 2 complained of significant pain at the time of surgery, by the and Figure 1). This represents a 21% reduction in mean AHI outcome point (on average 7.2 months after the final procedure), after LAUP. There was one subject who had a more than 50% 13 of 21 (62%) said that they had little or no difficulty underincrease in AHI after LAUP (AHI increased from 10.6 to 16.7 going the treatment. Eight of 21 (38%) said they had moderate per hour [58% increase]). This patient had a 7-kg weight gain. to severe difficulty. Despite the reported level of dissatisfaction Two subjects refused more procedures after the first procedure and level of difficulty associated with LAUP, 17 subjects (81%) because of severe pain despite analgesia and despite incomplete would have recommended it to a friend, and 13 subjects (62%) resolution of symptoms and snoring. Five subjects went on nasal would have undergone it again knowing what they knew at the continuous positive airway pressure therapy, and one patient end of the study. had a septoplasty after completion of the study (Table 3). In the control group (no therapeutic intervention), 4 of 24 (16.7%) were treatment successes (AHI, 10 or less), and 17 DISCUSSION of 24 (70.8%) were treatment failures (AHI, more than 10). The results of this randomized controlled trial of LAUP in mild Although the AHI was lower at outcome in some patients with OSA indicate that LAUP is effective in some patients for the no intervention, no patient had a resolution of symptoms; hence, treatment of mild OSA. Twenty-four percent of subjects had a there were no complete responses in the control group. The reduction in AHI to 10 or less, and 4 of 21 (19%) had a complete pretreatment AHI was per hour. At outcome in the control group, it increased to per hour, but this increase was not significant (Table 2 and Figure 1). There was no difference in sleep architecture, awakenings, or sleep efficiency with the LAUP or in the control group compared with pretreatment values and no difference in the magnitude of the changes. Side Effects and Complications A total of 52 separate laser procedures were performed in the active-treatment group. Side effects were common particularly in the first week after treatment. These side effects included sore throat, difficulty swallowing, bleeding, change in vocal quality, nasal regurgitation, and infection. Seventeen subjects (81%) reported moderate to severe pain immediately after the procedure (despite analgesia). Four subjects (19%) had persistent difficulty swallowing still present at outcome. It was described as an unusual sensation in the throat and discomfort with swallowing. It was mild in three of the subjects but was moderate in one. Four subjects (19%) experienced mild bleeding, and five (24%) reported moderate to severe bleeding episodes one of Figure 1. The AHI at baseline and at outcome in the LAUP group and which required medical attention. One patient (5%) described in the untreated control group. AHI was lower at outcome in the LAUP a change in vocal quality, but it was temporary. Five subjects group than at baseline (p 0.03) and was lower than in the control (24%) had nasal regurgitation for a brief period after surgery. group at outcome (p 0.03).

4 18 AMERICAN JOURNAL OF RESPIRATORY AND CRITICAL CARE MEDICINE VOL TABLE 3. PROCEDURES AND APNEA/HYPOPNEA INDICES OF THE PATIENTS BEFORE AND AFTER UVULOPALATOPLASTY TREATMENT LAUP Group (n 21) Subject Number of Reason for No Further Treatment Post Number Baseline Outcome Procedures Procedures Study Snoring reduced Patient refused more surgery CPAP Snoring reduced CPAP Maximum tissue removed CPAP Maximum tissue removed CPAP Snoring reduced Maximum tissue removed Snoring reduced Snoring reduced Septoplasty Snoring reduced CPAP Snoring reduced Snoring reduced Snoring reduced Patient refused more surgery Snoring reduced Snoring reduced Snoring reduced Maximum tissue removed Patient refused more surgery Maximum tissue removed Maximum tissue removed Mean SD Min Max Definition of abbreviation: CPAP continuous positive airway pressure; LAUP laser-assisted uvulopalatoplasty. In some of these studies, patients had additional surgery to LAUP, and how snoring improvement was measured was not always defined. One potential explanation for our relatively low snoring success rate was that we followed up with all subjects in the trial, and our follow-up was on average 7.2 months after the last LAUP procedure. In the immediate postsurgical period, many subjects in our study reported major reductions in snoring intensity and frequency, but this was not always sustained. This has been shown in other studies where long-term follow-up took place (17, 20, 23, 24). It is possible that success of the LAUP procedure in this study may have been less beneficial for snoring and the reduction in AHI if we had followed up with patients 1 to 2 years after the procedure. It is a limitation of our study that we did not objectively measure snoring. However, even if there was an objective improvement in snoring intensity, it is more relevant clinically that the bed partner is satisfied with the reduction in snoring, and in this study, snoring was rated as improved in 48% of subjects after LAUP. In one study where snoring was objectively measured, the snoring index was not significantly different in the group after LAUP (6). It is known that there may be a significant discrepancy between the objective and subjective outcome of UPPP for snoring improvement when measured many months after UPPP (25). Miljeteig and colleagues sent questionnaires to 100 patients after UPPP (25). Sixty-nine patients replied to the questionnaire, and 78% reported that their snoring was re- duced or cured. When snoring was measured during polysomnography, there was no difference in measured snoring (loudness or snoring index) or AHI an average of months after the UPPP. Patients may therefore report better snoring results than have actually occurred. Only one patient (5%) had a significant worsening of OSA after laser surgery, and this was in the setting of a large weight gain (7 kg). Other studies have found that a significant proportion of patients, approximately 20 to 25%, have worsening of the response (in terms of AHI and a satisfactory resolution of symptoms. Overall, the reduction in AHI was small. Subjective snoring was significantly better in some subjects, but excessive daytime sleepiness and quality of life were not improved (when treatment related side effects were taken into consideration). Untreated subjects in the control group had no change in the AHI. If the reduction in AHI were related to night-to-night variability or to regression to the mean, then a similar change would have been expected in the control group. This study does not support the routine use of LAUP in patients with mild OSA because of the limited efficacy of this treatment. There are other ways to present surgical success rates. When success is defined as a more than 50% reduction in AHI, then LAUP was effective in 19% of our subjects. Kamami reported one of the earliest studies on LAUP in OSA on a group of 63 patients (14). The number and extent of the LAUP procedures was not given, and the length of follow-up was not stated. An unspecified number of subjects underwent laser turbinectomy in addition to LAUP. The study reported that 55 of 63 subjects (87%) had a more than 50% reduction in AHI with surgery. Other studies have not replicated this high success rate. Most report that 31 to 58% of subjects have a more than 50% reduction in AHI (17 20). Clearly, this is not an optimal definition of success because the post-treatment AHI could still be clinically important even if it is reduced 50% from baseline. In studies that reported the number of subjects with an AHI of less than 10 per hour after LAUP, the range of success was between 24 and 44% (6, 17, 18, 21). The results of this randomized study are similar to these precomparison and postcomparison studies with 24% of the subjects having a post-laup AHI of 10 or less per hour. Our success rate with snoring (48% improved) was lower than in many other LAUP studies. Most studies report, at least initially, that approximately 50 to 95% of patients have a major improvement in or a cure of their snoring (12 15, 17, 22, 23).

5 Ferguson, Heighway, and Ruby: LAUP in Mild OSA 19 AHI after the procedure (6, 15, 16, 18, 22, 23). This is a concernsleep controlled study of a mandibular advancement splint for obstructive apnea. Am J Respir Crit Care Med 2001;163: ing result, as many patients do not undergo adequate objective 4. Kamami Y. Laser CO 2 for snoring: preliminary results. Acta Otorhinolarfollow-up and there is too heavy of a reliance on patient selfyngol Belg 1990;44: report. Follow-up sleep studies are therefore essential to estab- 5. Hawke M, Josephson R. Interview with Dr. Yves-Victor Kamami: origilish objectively treatment outcome after LAUP. nator of laser-assisted uvulopalatoplasty. J Otolaryngol 1994;23:387 A potential criticism of this study is that it had a small sample 390. size. However, the study was adequately powered to detect a 6. Ryan CF, Love LL. Unpredictable results of laser assisted uvulopala- 25% improvement in AHI in the LAUP group and follow-up toplasty in the treatment of obstructive sleep apnoea. Thorax 2000; 55: was complete. Any less of an improvement is unlikely to be 7. American Sleep Disorders Association. Practice parameters for the use clinically relevant. Another potential criticism is that the study of laser-assisted uvulopalatoplasty. Sleep 1994;17: evaluated only one surgical technique. We did not find that the 8. Littner M, Kushida CA, Hartse K, Anderson WM, Davila D, Johnson transpalatal trench approach with subtotal uvulectomy and a SF, Wise MS, Hirshkowitz M, Woodson BT. Practice parameters for reduction of soft palate was an effective treatment for OSA, the use of laser-assisted uvulopalatoplasty: an update for Sleep and the effect on snoring was modest. The patients did have an 2001;24: Ryan CF. Laser assisted uvulopalatoplasty in sleep disordered breathing. average of procedures each. Six subjects had a poor Thorax 1997;52:5 8. clinical response, and the surgeon felt that no more tissue could 10. Johns MW. A new method for measuring daytime sleepiness: the Epbe safely removed. Three patients had a poor result and refused worth sleepiness scale. Sleep 1991;14: more surgery. Perhaps more surgery might have helped some 11. Flemons WW, Reimer MA. Development of a disease-specific health- of the patients with a suboptimal result. It is possible that the related quality of life questionnaire for sleep apnea. Am J Respir Crit LAUP procedure that is more similar to UPPP would have Care Med 1998;158: Krespi YP, Pearlman SJ, Keidar A. Laser-assisted uvulo-palatoplasty for better results. Our subjects complained vigorously about the snoring. J Otolaryngol 1994;23: amount of pain from surgery during the first several days after 13. Kamami YV. Outpatient treatment of snoring with CO 2 laser: lasersurgery and complications such as a change in swallowing oc- assisted UPPP. J Otolaryngol 1994;23: curred even with the lesser surgical procedure. The more extenlaser: 14. Kamami YV. Outpatient treatment of sleep apnea syndrome with CO 2 sive procedures are likely to have more side effects and complications laser-assisted UPPP. J Otolaryngol 1994;23: than the more limited approach. Furthermore, the overall 15. Walker RP, Grigg-Damberger MM, Gopalsami C, Totten MC. Laser- assisted uvulopalatoplasty for snoring and obstructive sleep apnea: success of UPPP for OSA is only 40.7% when response was results in 170 patients. Laryngoscope 1995;105: defined as a reduction in AHI of 50% with a postoperative AHI 16. Mickelson SA. Laser-assisted uvulopalatoplasty for obstructive sleep apof less than 20 or a postoperative AHI of less than 10 (26). It nea. Laryngoscope 1996;106: is unlikely that the more aggressive LAUP procedure would 17. Mickelson SA, Ahuja A. Short-term objective and long-term subjective equal or exceed the results of UPPP. results of laser-assisted uvulopalatoplasty for obstructive sleep apnea. Laryngoscope 1999;109: Conclusion 18. Walker RP, Grigg-Damberger MM, Gopalsami C. Laser-assisted uvulopalatoplasty for the treatment of mild, moderate, and severe obstruc- This randomized, controlled study has shown that LAUP is mini- tive sleep apnea. Laryngoscope 1999;109: mally effective in improving OSA in a group of unselected pa- 19. Hanada T, Furuta S, Tateyama T, Uchizono A, Seki D, Ohyama M. Laserassisted tients who all underwent the procedure. Nonetheless, roughly uvulopalatoplasty with Nd:YAG laser for sleep disorders. half of the patients were satisfied with the LAUP treatment. Laryngoscope 1996;106: Although snoring is improved in some patients, many continued 20. Finkelstein Y, Stein G, Ophir D, Berger R, Berger G. Laser-assisted uvulopalatoplasty for the management of obstructive sleep apnea: to snore after surgery and continued to have symptoms of OSA, myths and facts. Arch Otolaryngol Head Neck Surg 2002;128: including impaired quality of life. This study was not adequately 21. Pribitkin EA, Schutte SL, Keane WM, Mao V, Cater JR, Doghramji K, powered to evaluate treatment safety because major complica- Youakim JM, Rosen MR, Breuninger W. Efficacy of laser-assisted tions are likely to be rare and not necessarily seen in 21 patients uvulopalatoplasty in obstructive sleep apnea. Otolaryngol Head Neck undergoing the procedure. Finally, the study was not powered Surg 1998;119: Lauretano AM, Khosla RK, Richardson G, Matheson J, Weiss JW, to predict in whom LAUP is likely to be an effective therapy. Graham C, Fried MP. Efficacy of laser-assisted uvulopalatoplasty. A larger controlled study would be required to determine the Lasers Surg Med 1997;21: true complication rate of LAUP and the clinical and other fea- 23. Berger G, Finkelstein Y, Ophir D. Laser-assisted uvulopalatoplasty for tures associated with a good treatment outcome. snoring: medium-to long-term subjective and objective analysis. Arch Otolaryngol Head Neck Surg 2001;127: References 24. Wareing MJ, Callanan VP, Mitchell DB. Laser-assisted uvulopalatoplasty: six and eighteen month results. J Laryngol Otol 1998;112: Loube DI, Gay PC, Strohl KP, Pack AI, White DP, Collop NA. Indica tions for positive airway pressure treatment of adult obstructive sleep 25. Miljeteig H, Mateika S, Haight JS, Cole P, Hoffstein V. Subjective and apnea patients: a consensus statement. Chest 1999;115: objective assessment of uvulopalatopharyngoplasty for treatment of 2. Ferguson KA, Ono T, Lowe AA, Al-Majed S, Love LL, Fleetham JA. snoring and obstructive sleep apnea. Am J Respir Crit Care Med 1994; A short term controlled trial of an adjustable oral appliance for the 150: treatment of mild to moderate obstructive sleep apnoea. Thorax 1997; 26. Sher AE, Schechtman KB, Piccirillo JF. The efficacy of surgical modifica- 52: tions of the upper airway in adults with obstructive sleep apnea syndrome. 3. Mehta A, Qian J, Petocz P, Darendeliler MA, Cistulli PA. A randomized, Sleep 1996;19: