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(Chest. 2006;129:81-87.)
© 2006 American College of Chest Physicians

Snoring Is Not Relieved by Nasal Surgery Despite Improvement in Nasal Resistance*

Paula Virkkula, MD, PhD; Adel Bachour, MD, PhD; Maija Hytönen, MD, PhD; Tapani Salmi, MD, PhD; Henrik Malmberg, MD, PhD; Kirsti Hurmerinta, DDS, PhD and Paula Maasilta, MD, PhD, FCCP

* From the ENT Hospital (Drs. Virkkula, Hytönen, and Malmberg), the Departments of Clinical Neurophysiology (Dr. Salmi) and Pulmonary Medicine (Drs. Bachour and Maasilta), and the Cleft Palate Center (Dr. Hurmerinta), Department of Plastic Surgery, Helsinki University Central Hospital, Helsinki, Finland.

Correspondence to: Paula Virkkula, MD, PhD, ENT Hospital, Helsinki University Central Hospital, Haartmaninkatu 4.E., PO Box 220, FIN-00029 HUS, Helsinki, Finland; e-mail: paula.virkkula{at}hus.fi

Abstract

Objectives: In the present study, we evaluated the effect of nasal surgery on snoring time, snoring intensity, and sleep-disordered breathing. The role of abnormal cephalometry in treatment outcome was assessed.

Design: A cross-sectional prospective study.

Setting: University teaching hospital.

Patients: Forty consecutive snoring men who were referred to ENT Hospital because of a snoring problem or suspicion of sleep apnea.

Interventions: The patients underwent anterior rhinomanometry and polysomnography (PSG) with recording of snoring before and after operative treatment of nasal obstruction. Cephalometric radiographs were obtained before surgery.

Results: Nasal resistance decreased significantly in the overall patient group. Snoring time, snoring intensity, nocturnal breathing, and sleep architecture did not change after nasal surgery. Cephalometry did not predict operative outcome in these patients. Snoring intensity was found to be significantly higher during non-rapid eye movement (NREM) sleep than during rapid eye movement sleep.

Conclusions: Operative treatment of mainly structural nasal obstruction did not seem to decrease snoring intensity, snoring time, or sleep-disordered breathing in an objective assessment by PSG performed after surgery. The effect of treating inflammatory nasal changes during nocturnal breathing, as well as the role of cephalometry in the prediction of treatment outcome will need further evaluation. Higher snoring intensity related to NREM sleep may add to the sleep disturbance of a bed partner in the evening.

Key Words: nasal obstruction • polysomnography • rhinomanometry • sleep apnea • snoring • surgery • treatment outcome

A relationship between nasal obstruction and snoring or sleep-disordered breathing (SDB) has been found in several previous studies,1 suggesting that SDB can be worsened by nasal obstruction and can even result from it. Nasal resistance has been found to be higher in snorers when compared with nonsnorers, and in SDB when compared with primary snoring.23 However, a causal relationship between nasal obstruction and SDB has not been substantiated beyond controversy due to the lack of qualified prospective follow-up studies. Nocturnal nasal congestion has been shown to be a strong independent risk factor for habitual snoring.4 In subjects with long-term nasal congestion occurring always or almost always at night, the risk of habitual snoring increased from 3.6-fold to 4.9-fold when compared with subjects without nasal congestion in a 5-year follow-up.

Operative treatment of nasal obstruction has relieved nocturnal breathing only modestly or in a limited number of patients, with the response ranging between 0% and 35%.567891011 Sériès and coworkers7 reported improvement in obstructive sleep apnea obtained by nasal surgery in patients with normal cephalometry findings when compared with patients with abnormal cephalometry findings. The effect of surgical and nonsurgical nasal treatment on snoring seems to be controversial. Treatment outcome has been evaluated by subjective methods (ie, questionnaires or visual analog scales) in several uncontrolled studies.121314151617181920 In patients with nasal pathology, the objective measurement of snoring has not given consistent results regarding treatment outcome.10212223

The purpose of the present study was to evaluate the outcome of nasal surgery on snoring time, snoring intensity, and SDB. Objective measurements of nasal resistance were performed before and after surgery, and the criteria for improved nasal patency that were assumed to have clinical importance were defined. Treatment results were investigated separately in a subgroup of patients with well-improved structural nasal obstruction. The role of normal cephalometry, as defined earlier,7 on surgical outcome was evaluated.

Materials and Methods

Patients and Study Design
The study population consisted of 40 consecutive men who had been referred to the ENT Hospital at Helsinki University Central Hospital because of a snoring problem or suspicion of sleep apnea and were scheduled for surgical treatment of nasal obstruction.242526 Only one patient had undergone septoplasty earlier, but other upper airway surgery for SDB had not been performed. The evaluation for nasal surgery had been based on symptoms, and anterior rhinoscopy and anterior rhinomanometry (RMM) findings without strict criteria for nasal resistance. The mean age of the patients was 44.2 years (SD, 9.5 years; age range, 26 to 62 years), and the mean body mass index (BMI) was 27.9 kg/m2 (SD, 3.4 kg/m2; range, 22 to 37 kg/m2). The mean total nasal resistance (TNR) was 0.574 Pa/cm3/s (SD, 0.597 Pa/cm3/s) without decongestion and 0.355 Pa/cm3/s (SD, 0.339 Pa/cm3/s) after decongestion of the nasal mucosa. All patients were of Finnish origin. None of the patients used sedatives regularly. Thirty-two percent of the patients reported daytime sleepiness every day or almost every day. The mean Epworth sleepiness scale (ESS) score was 6.3 (SD, 3.7). All patients complained of nasal obstruction, and five patients had a history of allergic rhinitis (13%). Two patients used corticosteroid sprays, and one patient used an antihistamine regularly. Twenty patients (50%) were smokers.

Most of the patients underwent septoplasty with or without partial resection of the inferior turbinates. Septoplasty was performed in all patients using the same technique of mobilization, straightening, and reinserting the straightened cartilage. Septorhinoplasty was performed in two patients, and partial resection of the inferior turbinates was carried out in the other two subjects. The patients underwent preoperative and postoperative active anterior RMM and polysomnography (PSG). Cephalometric radiographs were obtained before surgery. Postoperative RMM was performed, at the earliest, 2 months after the operation (mean time to RMM, 125 days; range, 76 to 247 days). The patients underwent a second sleep study 63 to 176 days after surgery (mean time to sleep study, 113 days).

The Ethical Committee of the Department of Otorhinolaryngology of Helsinki University Central Hospital has approved the study. Informed consent was obtained from the study subjects.

Cephalometry
Cephalometric analysis was carried out before nasal surgery with patients in upright and supine body positions, as has been described.25 The group of patients with normal cephalometry findings consisted of patients with a posterior airway space (ie, the minimal distance between the base of the tongue and the posterior pharyngeal wall [ph1-ph2]) of > 7.0 mm, and a perpendicular distance from the hyoid bone to the mandibular plain (H/MP) of < 23 mm.7

RMM
RMM was performed without nasal decongestion with the patient in a supine position after lying down for 5 min and with nasal decongestion in a seated position, as was reported earlier.24 Inspiratory nasal resistance at radius 200 was calculated according to the method of Broms et al.27 TNR was calculated from recordings obtained from the left and right sides. We used the logarithmic transformation of rhinomanometric data in the statistical analysis. Nasal surgery was mainly aimed at relieving structural obstruction, and thus the measurement of decongested nasal mucosa was used in the evaluation of operative outcome.28 With criteria of ≥ 20% operative improvement in TNR of the decongested nasal mucosa, 25 patients were stratified into a subgroup of surgically improved patients. A subgroup of patients with no improvement consisted of 15 patients with < 20% improvement in nasal resistance after decongestion.

PSG
As reported previously,29 the overnight hospital recordings were performed using a computerized 24-channel polygraph (Alice 3; Healthdyne Technologies; Marietta, GA). It included a four-channel EEG (C3/A2, C4/A1, O1/A2, and O2/A1), an electro-oculogram, and submental and leg electromyograms. Airflow was detected by monitoring with a nasal and oral thermistor (Healthdyne Technologies). Thoracic and abdominal belts (Healthdyne effort sensor; Healthdyne Technologies) were used for respiratory movement detection. A pulse oximeter (BCI Oximetry 3100; BCI International; Waukesha, WI) and a body position sensor (Healthdyne) were included in all recordings. Snoring was detected as previously described29 with a microphone attached to the subject’s throat, and the analog signal was transferred to the monitor screen. Another microphone was attached to the ceiling, 2 m from the patient’s head, to record sounds on a videotape.

During the calibration process, the subjects were asked to imitate snoring as loud as they could while lying supine before the start of the recording. The maximal snoring signal during calibration was given a value of 100 on an arbitrary scale from 0 to 100. With a snoring signal of 50, no snoring was heard on the videotape. A snoring event was scored visually if the signal was at least 50% of the calibration signal. A snoring episode included at least one snoring event and terminated when no snoring event was detected for two breathing cycles. The time spent in snoring episodes was divided by total sleeping time to give the figure for snoring time.

The power of the snoring signal was measured for a period of 10 consecutive snoring cycles (one inspiration and expiration), which was visually selected to reflect the most intensive snoring episodes, using the following formula:

Formula
where V = m volt and n = the number of samples.

The sampling frequency was 40 Hz. Samples were derived from episodes in rapid eye movement (REM) and non-REM (NREM) sleep, recorded with the patient in the supine and nonsupine position before and after undergoing septoplasty.

Figure 1 shows the snoring signal that corresponds to calculated snoring intensity indexes of 71 and 62. Sleep and breathing were scored as described previously using international criteria.29 The scorer was blinded to other clinical data.


Figure 1
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  		Figure 1.. Snoring signals corresponding to calculated snoring intensity indexes of 71 and 62.

 
Statistical Analysis
The sample size of 40 patients was based on the capability of that sample for showing a 0.5 SD reduction in snoring time after nasal surgery, with an {alpha} error of 0.05 and a testing power of 0.80. The SD was based on a clinical sample of 100 snorers who had been referred to our clinic earlier. Differences between the subgroups were evaluated using the Mann-Whitney U test. Comparisons of snoring intensity between REM sleep and NREM sleep, between supine and nonsupine sleep position, and between preoperative and postoperative measurements were analyzed using the Wilcoxon matched-pair test. A Pearson correlation analysis was used to evaluate the relationship between the change in REM sleep time and the change in snoring time.

The computations were performed using a commercial statistical package (Statistica, version 5.1; Statsoft Inc; Tulsa, OK). A p value of < 0.05 was considered to indicate statistical significance.

Results

After nasal surgery, the TNR decreased significantly in the overall patient group. A decrease in nasal resistance was found both in the baseline measurement without nasal decongestion and after decongestion of the nasal mucosa (p < 0.05 for both). After nasal surgery, both baseline and decongested nasal measurements showed improvement in nasal patency in the subgroup of surgically improved patients (p < 0.05 for both), but not in the subgroup with no improvement in nasal resistance (Table 1 ).


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  		Table 1.. Patient Characteristics and Preoperative Data on Rhinomanometry in Patients With ≥ 20% of Operative Improvement in the TNR of Decongested Nasal Mucosa and in Patients With No Improvement of Mean TNR*

 
Snoring time did not decrease after nasal surgery in the overall patient group or in the subgroups (Fig 2 ). The preoperative snoring intensity index was 68.8 (SD, 10.0) during NREM sleep and 65.6 (SD, 7.4) during REM sleep. The postoperative snoring intensity index was 70.7 (SD, 7.3) during NREM sleep and 66.5 (SD, 8.7) during REM sleep. Preoperative and postoperative snoring intensity indexes did not change significantly in the overall patient sample or in the subgroups. The snoring intensity index was found to be significantly higher during NREM sleep than during REM sleep in both sleep studies (p < 0.05 for both). No significant changes in the snoring intensity index were noticed between patients in the supine and nonsupine position during REM or NREM sleep.


Figure 2
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  		Figure 2.. Individual snoring times (as the percentage of total sleeping time) in 40 consecutive snoring men prior to nasal surgery (PRE) and following nasal surgery (POST). The following subgroups were determined according to nasal improvement: patients in whom nasal resistance did not improve significantly after surgery; and patients in whom nasal resistance improved ≥ 20% after surgery.

 
Table 2 shows preoperative and postoperative PSG data in the overall patient group, and in the subgroups with surgical improvement and no improvement of nasal patency. There were no statistical differences in preoperative breathing or sleep parameters between the subgroups (Table 2). REM sleep increased after the operation in the overall patient group and in the subgroup with surgical improvement (p < 0.05 for both). The change in REM sleep time was not correlated to the change in snoring time. BMI did not change between the sleep studies. ESS score remained unchanged in the overall patient group.


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  		Table 2.. PSG Data Before and After Nasal Surgery in the Overall Patient Group, in Patients With Clear Improvement in Structural Nasal Patency After Surgery and in Patients With No Significant Improvement in Nasal Patency

 
The mean H/MP was 22.0 mm (SD, 5.8 mm), and the mean ph1-ph2 was 10.5 mm (SD 2.8, mm). Using the criteria reported by Sériès and coworkers7 for H/MP and ph1-ph2, no statistical difference in improvement of apnea-hypopnea index (AHI), oxygen desaturation index, arousals, or snoring time was found between the subgroups of patients with normal cephalometry findings (n = 20) and abnormal cephalometry findings (n = 16). In the group with normal cephalometry findings in which the patients were expected to improve, the mean nasal resistance with decongestion of the nasal mucosa decreased by 34% between preoperative and postoperative measurements.

Discussion

Nasal surgery that aimed to relieve nasal obstruction did not decrease snoring time in our sample of 40 consecutive men who had been referred to an ear, nose, and throat clinic for snoring or suspicion of sleep apnea. Nor did we find changes in snoring intensity, as maximal intensity periods were selected from recordings of supine and nonsupine sleep, and from NREM and REM sleep. Evaluation of the subgroup with a clear decrease of nasal resistance after decongestion of the nasal mucosa (ie, improvement of structural obstruction) did not change the results. The evaluation of the subjective outcome of nasal symptoms and snoring was beyond the scope of this study.

Objective snoring measurement has been performed earlier in one surgical study and in some studies using nasal dilators, nasal decongestants or topical corticosteroids.10212223303132333435 Some studies19212223303135 have reported the degree of nasal obstruction before and after treatment by objective nasal measurement. Patient samples in nonsurgical studies have varied from subjects without nasal symptoms or signs of nasal pathology to unselected snorers and those with abnormal rhinoscopy findings.

Despite mainly good treatment outcomes in subjective markers of snoring, objective snoring recordings in patients with nasal pathology who were treated surgically or with dilators have given controversial results.1021222335 A randomized placebo-controlled study in patients with nasal pathology investigated 12 nonobese patients with chronic rhinitis and without other ENT abnormalities. In these patients with an AHI of < 20, snoring frequency (ie, the number of snores per hour of sleep) decreased when using the nasal dilator compared with use of the placebo.22 Snoring loudness did not decrease. Our patients were consecutive snoring men who primarily had a structural nasal obstruction. Other ear, nose, and throat pathologies were not excluded, but nasal surgery had been chosen as a first-line treatment. It is possible that the differing results are due to the selected sample in the former study, the differences in the measurement of snoring, or study design. In the present study, better sleep in the second sleep study due to the so-called first night effect might have decreased the possible beneficial effect of treatment on snoring to some degree. We could not find a significant relationship between the change in REM sleep time and the change in snoring time in a correlation analysis. Moreover, other studies102123 on applying nasal strips, topical corticosteroids, and nasal surgery seemed to support our findings.

Hoffstein and coworkers36 did not find differences in the mean or highest sound intensity across the sleep stages in heavy snorers. However, Nakano and coworkers37 reported increased snoring time and intensity during slow-wave sleep, when compared to REM sleep in apneic snorers. In the present study, the snoring intensity index was also found to be significantly higher during NREM sleep than during REM sleep in both sleep studies. Snoring seems more prevalent and more intense during stages 2 to 4 of NREM sleep.363738 Since REM sleep is more prevalent in the early morning and sleep onset is followed by stages of NREM sleep,39 increased intensity of snoring during NREM sleep may have social implications.

Previous studies78910112223 have shown moderate decreases or no significant changes in nocturnal breathing disorders after treatment of nasal obstruction. Kiely and coworkers23 reported a significant decrease in AHI after intranasal corticosteroid therapy in a randomized placebo-controlled study of patients with symptoms of rhinitis. Variation in treatment outcome was noted, as was the case in other studies, but the change in apneic activity was correlated with the change in nasal resistance. Verse and coworkers9 followed snoring patients after nasal surgery for more than a year on average without improvement in SDB in the whole patient group, but they found a significant decrease in the number of arousals and improvement of daytime sleepiness as determined by ESS score. Improvements in sleep architecture (eg, increase in REM sleep) have been observed after treatment of severe nasal obstruction.11 Subjective improvement of sleep quality and daytime somnolence is frequently reported, although controlled studies of treatment outcome in nasal pathology are few.23 We found no improvement in nocturnal breathing, number of arousals, or ESS score in these patients despite an improvement in nasal resistance. This is probably mainly due to the large variety of influencing factors in an unselected clinical sample.

Variable treatment outcomes can be hypothesized to reflect differences in other obstructive sites. Sériès and coworkers7 reported better outcomes after nasal surgery in patients with normal cephalometry in 14 patients who were matched for SDB and BMI. In six of seven patients with a wide ph1-ph2 and a short H/MP as criteria for normal cephalometry findings, the AHI returned to < 10 and the number of arousals decreased. In the group of patients with abnormal cephalometry findings, none of the patients were cured by nasal surgery. In consecutive patients taken from our waiting list of patients for nasal surgery, these results could not be confirmed.

RMM is a physiologic noninvasive method for the evaluation of nasal patency. Nasal resistance increases when the patient is in the supine position, and it is influenced by arterial CO2, pain and fear, tactile stimuli, temperature, and humidity. Alternating congestion of the capacitance vessels of the nasal mucosa is the most important factor modulating unilateral nasal resistance.40 A decongested nasal mucosa is less dependent on these physical and physiologic factors, and decongestion is recommended for the evaluation of structural nasal obstruction.28 The fact that patients with more severe nasal obstruction preoperatively obtained a greater decrease in nasal resistance seems natural. The relationship between nasal resistance and BMI is unknown.

There is no agreement about how to measure snoring. However, repeated measurements before and after intervention will show changes reliably, assuming that snoring characteristics recorded during the study are those that are essential for the human ear too.41 In this study, snoring time was measured when snoring intensity exceeded a level that had been preset at calibration. The recorded snoring intensity was compared with perceived snoring sounds during the calibration process.

It is, of course, possible that our negative findings are only due to the methodology. Discordance between perceived and recorded snoring has been reported.41 The results may differ depending on the population studied. Whether a single-night recording of snoring is adequate remains unknown as the repeatability of these measurements is also unknown. Furthermore, how much nasal resistance should be reduced to show a possible effect on snoring also is not clear.

In addition to relieving symptoms of nasal stuffiness, the treatment of nasal obstruction has been shown8 to decrease the needed pressure levels in nasal continuous positive airway pressure therapy, and it may increase adherence to the treatment.42 Although nasal obstruction seems to predispose patients to snoring and probably to SDB, the relief of nasal obstruction by nasal surgery as a single treatment for snoring or SDB does not seem adequate in a clinical population of problem snorers. Only some habitual snorers develop obstructive sleep apnea, and the factors influencing the course of the disease are poorly understood. Inflammation, snoring trauma, and changes in the pharyngeal soft tissues have been related to the development of obstructive sleep apnea.43 Changes in the upper airways over the course of years may decrease the effect of a unilevel treatment in patients with snoring and SDB. Nasal mucosal inflammation in patients experiencing habitual snoring and SDB may be a predisposing factor44 but may also be a consequence of the disease process.45 Moderate treatment results of sleep apnea in unselected patients with rhinitis symptoms are in agreement with this hypothesis.23 The treatment of nasal inflammation as well as structural obstruction may improve treatment results in the short term and may prevent more severe disease in the long term.

Conclusions

Snoring time and intensity measured during PSG were not improved by the treatment of structural nasal obstruction despite significant decrease in nasal resistance. Nocturnal breathing also did not improve significantly in these consecutive snoring men. Cephalometry for the prediction of treatment outcome will need further evaluation. Snoring intensity seems to be higher during NREM sleep when compared with REM sleep, which may have social implications predominantly during the first hours of sleep.

Footnotes

Abbreviations: AHI = apnea-hypopnea index; BMI = body mass index; ESS = Epworth sleepiness scale; H/MP = perpendicular distance from hyoid bone to mandibular plain; NREM = non-rapid eye movement; ph1-ph2 = minimal distance between base of the tongue and posterior pharyngeal wall; PSG = polysomnography; REM = rapid eye movement; RMM = active anterior rhinomanometry; SDB = sleep-disordered breathing; TNR = total nasal resistance

This study was supported financially by Helsinki University Hospital Special Funds.

Received for publication June 20, 2005. Accepted for publication August 27, 2005.

References

  1. Rappai, M, Collop, N, Kemp, S, et al (2003) The nose and sleep-disordered breathing: what we know and what we do not know. Chest 124,2309-2323[Abstract/Free Full Text]
  2. Young, T, Finn, L, Kim, H Nasal obstruction as a risk factor for sleep-disordered breathing. J Allergy Clin Immunol 1997;99,S757-S762[CrossRef][ISI][Medline]
  3. Lofaso, F, Coste, A, d’Ortho, MP, et al Nasal obstruction as a risk factor for sleep apnoea syndrome. Eur Respir J 2000;16,639-643[Abstract]
  4. Young, T, Finn, L, Palta, M Chronic nasal congestion at night is a risk factor for snoring in a population-based cohort study. Arch Intern Med 2001;161,1514-1519[Abstract/Free Full Text]
  5. Caldarelli, DD, Cartwright, RD, Lilie, JK Obstructive sleep apnea: variations in surgical management. Laryngoscope 1985;95,1070-1073[Medline]
  6. Sériès, F, St. Pierre, S, Carrier, G Effects of surgical correction of nasal obstruction in the treatment of obstructive sleep apnea. Am Rev Respir Dis 1992;146,1261-1265[ISI][Medline]
  7. Sériès, F, St. Pierre, S, Carrier, G Surgical correction of nasal obstruction in the treatment of mild sleep apnoea: importance of cephalometry in predicting outcome. Thorax 1993;48,360-363[Abstract]
  8. Friedman, M, Tanyeri, H, Lim, JW, et al Effect of improved nasal breathing on obstructive sleep apnea. Otolaryngol Head Neck Surg 2000;122,71-74[CrossRef][ISI][Medline]
  9. Verse, T, Maurer, JT, Pirsig, W Effect of nasal surgery on sleep-related breathing disorders. Laryngoscope 2002;112,64-68[CrossRef][ISI][Medline]
  10. Kim, ST, Choi, JH, Jeon, HG, et al Polygraphic effects of nasal surgery for snoring and obstructive sleep apnea. Acta Otolaryngol (Stockh) 2004;124,297-300
  11. McLean, HA, Urton, AM, Driver, HS, et al Effect of treating severe nasal obstruction on the severity of obstructive sleep apnoea. Eur Respir J 2005;25,521-527[Abstract/Free Full Text]
  12. Ellis, PD, Harries, ML, Ffowcs Williams, JE, et al The relief of snoring by nasal surgery. Clin Otolaryngol Allied Sci 1992;17,525-527
  13. Woodhead, CJ, Allen, MB Nasal surgery for snoring. Clin Otolaryngol 1994;19,41-44[Medline]
  14. Low, WK Can snoring relief after nasal septal surgery be predicted? Clin Otolaryngol 1994;19,142-144[Medline]
  15. Scharf, MB, Brannen, DE, McDannold, M A subjective evaluation of a nasal dilator on sleep & snoring. Ear Nose Throat J 1994;73,395-401[Medline]
  16. Löth, S, Petruson, B Improved nasal breathing reduces snoring and morning tiredness: a 6-month follow-up study. Arch Otolaryngol Head Neck Surg 1996;122,1337-1340[Abstract]
  17. Ibrahim, E, Sayed, NH The effect of nasal surgery on snoring. Am J Rhinol 1998;12,77-79[Medline]
  18. Löth, S, Petruson, B, Wirén, L, et al Better quality of life when nasal breathing of snoring men is improved at night. Arch Otolaryngol Head Neck Surg 1999;125,64-67[Abstract/Free Full Text]
  19. Bertrand, B, Eloy, P, Collet, S, et al Effect of nasal valve surgery by open-septorhinoplasty and lateral cartilage grafts (spreader grafts) on snoring among a population of single snorers: preliminary report. Acta Otorhinolaryngol Belg 2002;56,149-155[Medline]
  20. Akcam, T, Friedman, O, Cook, TA The effect on snoring of structural nasal valve dilation with a butterfly graft. Arch Otolaryngol Head Neck Surg 2004;130,1313-1318[Abstract/Free Full Text]
  21. Gosepath, J, Amedee, RG, Romantschuck, S, et al Breath Right nasal strips and the respiratory disturbance index in sleep related breathing disorders. Am J Rhinol 1999;13,385-389[Medline]
  22. Pevernagie, D, Hamans, E, Van Cauwenberg, P, et al External nasal dilation reduces snoring in chronic rhinitis patients: a randomized controlled trial. Eur Respir J 2000;15,996-1000[Abstract]
  23. Kiely, JL, Nolan, P, McNicholas, WT Intranasal corticosteroid therapy for obstructive sleep apnoea in patients with co-existing rhinitis. Thorax 2004;59,50-55[Abstract/Free Full Text]
  24. Virkkula, P, Maasilta, P, Hytönen, M, et al Nasal obstruction and sleep-disordered breathing: the effect of supine body position on nasal measurements in snorers. Acta Otolaryngol (Stockh) 2003;123,648-654
  25. Virkkula, P, Hurmerinta, K, Löytönen, M, et al Postural cephalometric analysis and nasal resistance in sleep-disordered breathing. Laryngoscope 2003;113,1166-1174[CrossRef][ISI][Medline]
  26. Virkkula, P, Bachour, A, Hytönen, M, et al Patient and bed partner-reported symptoms, smoking and nasal resistance in sleep-disordered breathing. Chest 2005;128,1276-1282
  27. Broms, P, Jonson, B, Lamm, CJ Rhinomanometry: II. A system for numerical description of nasal airway resistance. Acta Otolaryngol (Stockh) 1982;94,157-168
  28. Broms, P Rhinomanometry: III. Procedures and criteria for distinction between skeletal stenosis and mucosal swelling. Acta Otolaryngol (Stockh) 1982;94,361-370
  29. Maasilta, P, Bachour, A, Teramo, K, et al Sleep-related disordered breathing during pregnancy in obese women. Chest 2001;120,1448-1454[Abstract/Free Full Text]
  30. Höijer, U, Ejnel, H, Hedner, J, et al The effect of nasal dilation on snoring and obstructive sleep apnea. Arch Otolaryngol Head Neck Surg 1992;118,281-284[Abstract]
  31. Hoffstein, V, Mateika, S, Metes, A Effect of nasal dilation on snoring and apneas during different stages of sleep. Sleep 1993;16,360-365[ISI][Medline]
  32. Braver, HM, Block, AJ Effect of nasal spray, positional therapy, and the combination thereof in the asymptomatic snorer. Sleep 1994;17,516-521[Medline]
  33. Todorova, A, Schellenberg, R, Hofmann, HC, et al Effect of the external nasal dilator Breath Right on snoring. Eur J Med Res 1998;3,367-379[Medline]
  34. Schönhofer, B, Franklin, KA, Brünig, H, et al Effect of nasal-valve dilation on obstructive sleep apnea. Chest 2000;118,587-590[Abstract/Free Full Text]
  35. Djupesland, PG, Skatvedt, O, Borgersen, AK Dichotomous physiological effects of nocturnal external nasal dilation in heavy snorers: the answer to a rhinologic controversy? Am J Rhinol 2001;15,95-103[CrossRef][ISI][Medline]
  36. Hoffstein, V, Mateika, JH, Mateika, S Snoring and sleep architecture. Am Rev Respir Dis 1991;143,92-96[ISI][Medline]
  37. Nakano, H, Ikeda, T, Hayashi, M, et al Effects of body position on snoring in apneic and nonapneic snorers. Sleep 2003;2,169-172
  38. Perez-Padilla, JR, West, P, Kryger, M Snoring in normal young adults: prevalence in sleep stages and associated changes in oxygen saturation, heart rate, and breathing pattern. Sleep 1987;10,249-253[Medline]
  39. Krieger, J Respiratory physiology: breathing in normal subjects. Kryger, MH Roth, T Dement, WC eds. Principles and practice of sleep medicine 2000,229-241 WB Saunders. Philadelphia, PA:
  40. Flanagan, P, Eccles, R Spontaneous changes of unilateral nasal airflow in man: a re-examination of the "nasal cycle." Acta Otolaryngol (Stockh) 1997;117,590-595
  41. Hoffstein, V Snoring. Chest 1996;109,201-222[Free Full Text]
  42. Powell, NB, Zonato, AI, Weaver, EM, et al Radiofrequency treatment of turbinate hypertrophy in subjects using continuous positive airway pressure: a randomised, double-blind, placebo-controlled clinical pilot trial. Laryngoscope 2001;111,1783-1790[CrossRef][ISI][Medline]
  43. Boyd, JH, Petrof, BJ, Hamid, Q, et al Upper airway muscle inflammation and denervation changes in obstructive sleep apnea. Am J Crit Care Med 2004;170,541-546[Abstract/Free Full Text]
  44. Kramer, MF, de la Chaux, R, Fintelmann, R, et al NARES: a risk factor for obstructive sleep apnea? Am J Otolaryngol 2004;25,173-177[Medline]
  45. Welinder, R, Cardell, LO, Uddman, R, et al Reduced nasal airway resistance following uvulopalatoplasty. Rhinology 1997;35,16-18[Medline]



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Eur. Respir. J., December 1, 2007; 30(6): 1208 - 1215.
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Nasal Surgery in OSA Patients
Murat Enoz
Chest Online, 27 Jul 2007 [Full text]
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