Comparison of the pharyngeal airway in snoring and non-snoring patients based on the lateral cephalometric study: A case–control study

BACKGROUND

Normal airways are a key factor during the craniofacial growth of the young. Therefore, sleep-disordered breathing (SDB) without treatment can have harmful consequences for development and health.

OBJECTIVES

This study aimed to evaluate the cephalometric characteristics in non-snoring individuals and snoring subjects, and investigate differences in the pharyngeal airway space between the 2 groups.

MATERIAL AND METHODS

This case-control study included 70 patients aged over 18 years, selected from a radiology center. The patients were divided into 2 groups: case (35 patients with a history of habitual snoring); and control (35 healthy patients). The Berlin sleep questionnaire was administered to the parents of the patients. The nasopharyngeal airway was measured according to the analysis of Linder-Aronson (1970), and 4 indices were measured and analyzed in each of the lateral cephalometric radiographs.

RESULTS

No statistically significant differences were observed in the pharyngeal measurements between the 2 groups, although all means in the control group were higher than in the experimental group. However, there was a significant relationship between gender and the Ba-S-PNS and PNS-AD2 indices.

CONCLUSIONS

Although the patients with nocturnal snoring had smaller airway dimensions, their pharyngeal measurements were not significantly different from the control group.

The effects of adeno/tonsillectomy on cardiopulmonary function based on echocardiography indices in children with primary snoring and mild obstructive sleep apnea

BACKGROUND

The goal of this study was to evaluate the effects of adenotonsillectomy on heart function based on echocardiography indices in children with primary snoring (PS) and mild obstructive sleep apnea due to adenotonsillar hypertrophy (ATH).

METHODS

55 children (aged 7 to 11 years old) with PS and ATH who were a candidate for adenotonsillectomy from August 2018 to June 2019 evaluated. A history of Upper Respiratory Tract Obstruction was obtained, clinical examination was performed and the cases suspicious for moderate to severe degrees of Obstructive Sleep Apnea Syndrome were excluded. Echocardiography was performed one week before and 3-6 months after surgery. All data were analyzed by SPSS version 19 and P-value<0.05 was considered significant.

RESULTS

From 55 enrolled cases, 42 [30 boys (71.5%) and 12 girls (28.5%)] completed the study course. Tricuspid Annular Plane Systolic Excursion (TAPSE), Ejection Fraction (EF), Right Ventricular Peak Systolic Myocardial Velocity (RVSM), Right Ventricular Fractional Area Change (RVFAC) were increased significantly and Isovolumic Contraction Time (IVCT) index was decreased significantly after surgery (P-value<0.05). The difference of indices between the two sexes was not significant after surgery (P-value>0.05).

CONCLUSION

Adenotonsillectomy can improve cardiac function indices in patients with PS due to ATH especially in terms of right ventricle (RV) function and reduction in pulmonary artery pressure. So, although "subclinical", it is better to be considered PS not just as annoying noise for roommates before significant clinical cardiac problems happen.

Correlation between gonial angle and dynamic tongue collapse in children with snoring/sleep disordered breathing - an exploratory pilot study

BACKGROUND

Drug induced sleep endoscopy (DISE) is hoped to identify reasons of failure of adenotonsillectomy (AT) in treating pediatric sleep disordered breathing (SDB). Maxillomandibular disproportion has been studied as another association which may explain alternative pathogenesis of SDB. We aimed to explore the relation between the size of the gonial angle and inclination of the epiglottis measured from cone beam CT (CBCT) and tongue base collapse based on DISE in children with SDB.

METHOD

A retrospective chart review was conducted at a tertiary pediatric center. Children (6-17 years old) assessed at a multi-disciplinary Upper Airway Clinic, diagnosed with SDB and maxillo-mandibular disproportion (MMD), and who underwent DISE were eligible. Variables obtained from the electronic medical records of the clinic and prospective database included demographics, comorbidities, surgeries performed, investigations, DISE findings and CBCT findings. The gonial angle of subjects with and without tongue base collapse (TBC) on SNP were compared.

RESULTS

In total 29 patients (13 male, 8 female) age 6-17 (median= 9) were eligible for the study from January 2009 - July 2016. We included 11 subjects, and 10 comparators. The mean gonial angle of the TBC group was 139.3°± 7.6°, while that of the comparison group was 129.4°±3.5 (mean difference -9.937, 95% CI of -15.454 to - 4.421, P = 0.001, power of test 0.95). Additionally, the mean inclination of the epiglottis had a mild positive correlation (r=0.32, p<0.05) with the gonial angle, in the whole cohort.

CONCLUSIONS

This pilot study suggests that TBC may be mediated by a wider gonial angle in children with SDB patients. The posterior tilt of the epiglottis on CBCT may be a surrogate sign of TBC.

Non-apneic snoring and the orthodontist: radiographic pharyngeal dimension changes with supine posture and mandibular protrusion

OBJECTIVE

To evaluate the radiographic changes that occur in the pharynx and surrounding structures with alteration of posture from the upright to the supine position and the effect that mandibular protrusion whilst supine has on these dimensions.

DESIGN

Prospective cephalometric study.

SETTING

University Dental Hospital and School.

SUBJECTS AND METHOD

This prospective study involved 35 consecutively referred adults with proven non-apneic snoring. Lateral skull radiographs were obtained with the subjects upright in occlusion, supine in occlusion and supine with the mandible protruded to the maximum comfortable position. Radiographs were traced and digitized, and the pharyngeal dimensional changes and hyoid position were examined. Males and females were examined separately.

RESULTS

Radiographic pharyngeal dimensions were changed with altered posture, resulting in significant reductions in the minimum post-palatal (p<0.01) and post-lingual (p<0.05) airway measurements in the supine position. Mandibular protrusion whilst in the supine position produced increases in the functioning space for the tongue.

CONCLUSION

A supine posture results in significant reductions in pharyngeal airway measurements of non-apneic snorers. Mandibular protrusion whilst in the supine position produces an increase in the functioning space for the tongue.

Carotid intima-media thickness increase in patients with habitual simple snoring and obstructive sleep apnea syndrome is associated with metabolic syndrome

OBJECTIVES

Sleep disorders are emerging risk factors for atherosclerosis. Increased carotid intima-media thickness (CCA-IMT) is a surrogate marker of cardiovascular risk. The aim of the present study was to investigate the relationship between CCA-IMT and habitual simple snoring or obstructive sleep apnea syndrome (OSAS) and the other cardiovascular risk factors.

METHODS

Sleep disorders were diagnosed and staged by polysomnography. Patients were then classified into either habitual simple snoring (n = 20, group 1) or OSAS (n = 67, group 2), which was subclassified as mild-moderate (n = 27) or severe (n = 40). CCA-IMT was measured by B-mode ultrasonography. The other major risk factors were investigated.

RESULTS

The mean CCA-IMT was 0.65 ± 0.02 mm (mean ± SD) in group 1 versus 0.75 ± 0.02 mm in group 2 (p = 0.03). Using CCA-IMT ≥ 0. 9 mm as the threshold value also yielded significant results between the two groups (p = 0.03). The mean CCA-IMT did not differ between patients with mild-moderate and severe OSAS, whereas metabolic risk factors and metabolic syndrome (MS) were more prominent in the latter. Age, MS, neck and waist circumference, waist/ hip circumference, and fasting glucose level were higher in patients with CCA-IMT ≥ 0.9 mm.

CONCLUSIONS

CCA-IMT increase was associated with OSAS, but did not correlate with its severity, which could be due to the higher incidence of MS in this group.

[Cephalometry study of craniofacial growth in mixed dentition with OSAHS children]

OBJECTIVE

To investigate the craniofacial growth characteristics in mixed dentition of OSAHS and simple snoring (SS) children.

METHOD

Craniofacial morphology was studied by computerized cephalometric analysis in 24 children with OSAHS, 12 children with simple snoring and 34 healthy children.

RESULT

In OSAHS children, SNB (75.83 +/- 2.92) was significantly smaller than healthy children (P < 0.05), while ANB (5.83 +/- 2.76), Y axis angle (72.05 +/- 2.99), FH-MP (34.68 +/- 5.05), UI-SN (107.49 +/- 5.04) and LI-MP (98.38 +/- 5.28) were larger in comparison with healthy children (with the P values P < 0.01, P < 0.01, P < 0.01, P < 0.05 and P < 0.05, respectively). The GoGn in OSAHS children (57.20 +/- 5.64) was smaller than healthy children (P < 0. 05). In SS children, the indexes ANB (5.34 +/- 1.86), Y axis angle (67.42 +/- 4.53), FH-MP (31.62 +/- 4.60) and LI-MP (98.46 +/- 5.28) were also significantly larger than healthy children (with the P values P < 0.05, P < 0.01, P < 0.05 and P < 0.01, respectively). The GoGn in SS children (58.92 +/- 5.27) was also smaller (P < 0.05) than healthy children. All these indexes showed no significant differences between OSAHS children and SS children.

CONCLUSION

The effects of OSAHS and SS on craniofacial growth of children in mixed dentition include posterior displacement and shortening of mandible, heightening of anterior face and the labial inclination of maxillary central incisors and mandible central incisors. The change of breath mode was the main cause of these malformations.

Correlation between severity of sleep apnea and upper airway morphology: Cephalometry and MD-CT study during awake and sleep states

CONCLUSION

The data show that the evaluation of obstruction site in patients with obstructive sleep apnea (OSA) should be performed in the sleep state rather than in wakefulness.

OBJECTIVE

The aim of this study was to identify correlation between severity of OSA as measured by the apnea-hypopnea index (AHI) and upper airway morphology examined by cephalometry and dynamic multidetector computed tomography (MD-CT) in awake and sleep states.

METHODS

Polysomnography and cephalometry were performed in 94 patients with snoring or OSA. Among them, 64 patients underwent MD-CT study. Thirteen cephalometric variables were measured. We analyzed the correlations between AHI and MD-CT measurements - minimal cross-sectional area (mCSA) and collapsibility index (CI) in high retropalate (HRP), low retropalate (LRP), high retroglossal (HRG), and low retroglossal (LRG) areas.

RESULTS

Statistically significant correlations between the AHI and inferior displacement of the hyoid bone and pharyngeal length were identified in the cephalometric study. In wakefulness, AHI had a negative correlation with mCSA in the LRP area and a significant correlation with CI in LRP and HRG in MD-CT measurements. However, in the sleep state, the AHI had a negative correlation with mCSA in LRP, HRG, and LRG areas and a meaningful correlation with CI for the whole upper airway (HRP, LRP, HRG, and LRG).

Snoring in cleft patients with velopharyngoplasty

Some patients with cleft lip/palate or isolated cleft palate seem to develop snoring as one possible symptom of an obstructive sleep apnoea syndrome after velopharyngoplasty (VPP). The aim of this paper was to determine whether there was a difference in the posterior airway space (PAS) between patients with a VPP who snored and those who did not. Four standard parameters were measured in lateral cephalograms of 20 patients with cleft lip/palate and isolated cleft palate, without diagnosis of further syndromes (e.g. Pierre Robin sequence), having undergone VPP, to examine the dimensions of the PAS. Data were set in correlation to the symptom of snoring, and compared with those of 40 patients without cleft undergoing orthodontic treatment and with 20 patients with cleft lip/palate or isolated cleft palate but not VPP. Metric parameters were significantly different after VPP in patients with clefting and snoring compared to the group of cleft patients without snoring. All patients with clefts exhibited at least in one dimension a constriction when compared to patients without clefting. In conclusion, cleft lip/palate and isolated cleft palate patients tend to have constrictions of the PAS. VPP may induce snoring and further narrowing. Recall and analysis for obstructive sleep apnoea syndrome should be mandatory.

Effect of Obstructive Sleep Apnea on Aortic Elastic Parameters

BACKGROUND

Obstructive sleep apnea (OSA) syndrome has a critical association with cardiovascular mortality and morbidity. Aortic elastic parameters are important markers for left ventricular (LV) function and are deteriorated in cardiovascular disease.

METHODS AND RESULTS

Aortic elastic parameters and LV functions and mass were investigated in 40 patients with OSA (apnea - hypopnea index (AHI) >or=5) (mean age 51.3 +/-9 years, 32 males) and 24 controls (AHI <5) (mean age 51.9+/-5.2 years, 19 males). All subjects underwent polysomnographic examination and recordings were obtained during sleep. They also underwent a complete echocardiographic examination and systolic and diastolic aortic measurements were noted from M-mode traces of the aortic root. There were no significant differences in the demographic data of the patients with OSA and the controls. Subjects with OSA demonstrated higher values of aortic stiffness (7.1+/-1.88 vs 6.42+/-1.56, p=0.0001), but lower distensibility (9.47+/-1.33 vs 11.8+/-3.36, p=0.0001) than the controls. LV ejection fraction was significantly lower in patients with OSA when compared with the control group (61.3+/-5.2% vs 65.9+/-8.4%, p=0.0001). LV diastolic parameters were also compared and were worse in the subjects with OSA than in the control subjects (mitral E/A: 0.91 +/-0.42 vs 1.35+/-0.66, p=0.001; Em/Am: 0.86+/-0.54 vs 1.23+/-0.59, p=0.021). Respiratory disturbance index had a positive correlation with aortic stiffness (r=0.63, p=0.0001 and negative correlation with distensibility (r=-0.41, p=0.001).

CONCLUSION

Aortic elastic parameters are deteriorated in OSA, which has an extremely high association with cardiovascular disease. Increased aortic stiffness might be responsible for the LV systolic and diastolic deterioration in OSA syndrome.

Snoring Imaging

STUDY OBJECTIVES

To identify upper airway changes in snoring using CT scanning, to clarify the snoring mechanism, and to identify the key structures involved.

PARTICIPANTS

Forty patients underwent CT examination of the head and neck region according to snoring habits; patients were classified into non-snoring (n = 14), moderately loud snoring (n = 13), and loud snoring (n = 13) groups.

DESIGN

Comparative analysis.

MEASUREMENTS

Using CT images, areas, the anteroposterior and transversal distances of the pharyngeal space at different levels, and the thickness and length of the soft palate and uvula and their angle against the hard palate were measured; evidence of impaired nasal passages was noted; the extent of pharyngeal inspiratory narrowing was the ratio between the area at the hard palate level and most narrow area; and expiratory narrowing was the ratio between the area behind the root of the tongue and the most narrow area.

RESULTS

Greater pharyngeal inspiratory narrowing (p = 0.0015) proportional to the loudness of snoring (p = 0.0016), and a longer soft palate with uvula (p = 0.0173) were significant for snoring. Impaired nasal breathing was significantly related (p = 0.029) only to the loud snoring group. The body mass index and age of snoring persons were also significantly higher.

CONCLUSIONS

Snoring is associated with typical changes that can be revealed by CT scanning. Greater pharyngeal narrowing is the most important factor. Given the "Venturi tube" shape of the pharynx, the Bernoulli pressure principle plays a major role in snoring. The key structure in snoring is the soft palate: it defines the constriction and is sucked into vibrating by negative pressure that develops at this site. Its repetitive closures present an obstruction to breathing, producing the snoring sound, and should therefore be the target for causal treatment of snoring. Obstacles in the upper airway that increase negative inspiratory pressure could not be confirmed as important for the development of snoring, although they may increase its loudness.

Snoring and progression of coronary artery disease: The Stockholm Female Coronary Angiography Study

STUDY OBJECTIVES

Snoring is associated with a significant increased risk for acute myocardial infarction and stroke. However, our knowledge of mechanisms is still incomplete. The aim of the study was to investigate the influence of snoring in combination with feelings of tiredness on the 3-year progression of atherosclerosis in women with cardiovascular disease.

DESIGN

Repeated quantitative coronary angiograms were carried out with an average time interval of 3.25 years.

SETTING

Department of Thoracic Radiology at Karolinska Hospital, Stockholm, Sweden.

PARTICIPANTS

The study sample comprised 103 women cardiac patients with repeated, valid, and comparable measurement of quantitative coronary angiograms.

MEASUREMENTS AND RESULTS

Absolute luminal diameter (in mm) was measured in 10 predefined coronary segments. Mean segment diameter was calculated as the mean of all diameters measured along a given segment. The change over time was calculated by subtracting the first from the second measurement. Snoring and feelings of tiredness were measured by a short version of the Karolinska Sleep Questionnaire. We found that snoring women, after adjusting for age, waist-hip ratio, smoking, event at hospitalization, education, hypertension and alcohol intake, had a statistically significantly larger progression of atherosclerosis than did nonsnoring women (0.18 mm vs 0.07 mm change; P = .0006).

CONCLUSION

Snoring contributes to the atherosclerotic process and should be taken into consideration when treating patients with cardiac disease.

Dynamic upper airway soft-tissue and caliber changes in healthy subjects and snoring patients

BACKGROUND AND PURPOSE

The oropharyngeal airways are smaller in those who snore than in those who do not. We sought to determine which soft-tissue component surrounding the airways contributes to upper airway narrowing in those who snore.

METHODS

Ten control subjects and 19 snoring patients underwent CT, with 2-mm-thick axial sections obtained every 0.6 seconds during the respiration cycle at the same oropharyngeal level. We selected two sections with the widest and narrowest parts of the oropharyngeal airway to measure the anteroposterior and lateral dimensions of the airway and the thickness of the bilateral parapharyngeal fat pads, pterygoid muscles, and parapharyngeal walls. Mean values were calculated for each phase. For each subject, differences were calculated by subtracting the values in narrowest phase from those in the widest phase.

RESULTS

Changes in airway dimension (P < .05) and lateral parapharyngeal wall thickness (P < .01) were significantly different between snorers and control subjects. Changes in parapharyngeal wall thickness and transverse oropharyngeal airway diameter changes were significantly related (P < .01) in those who snored but not in control subjects.

CONCLUSION

Airway narrowing predominantly occurs in the lateral dimension in people who snore. Changes in the lateral pharyngeal wall are more important than the parapharyngeal fat pads in airway calibration. Narrowing of the upper airway area at the end of the expirium and the beginning of the inspirium is thought to be the cause of snoring and due to augmented muscle mass and prolonged laxity rather than inadequate activation of the pharyngeal dilating muscles.

Does the oropharyngeal fat tissue influence the oropharyngeal airway in snorers? Dynamic CT study

Objective

The aim of this study was to determine if snorers have a narrower oropharyngeal airway area because of fat infiltration, and an elevated body mass index.

Materials and Methods

Ten control subjects and 19 patients that snored were evaluated. We obtained 2-mm-thick axial CT scan images every 0.6 seconds during expiration and inspiration at the same level of the oropharynx. We selected the largest and the smallest oropharyngeal airway areas and found the differences. From the slice that had the smallest oropharyngeal airway area, the thickness of the parapharyngeal and subcutaneous fat was measured. The measurements from the left and right side were added together and single values for parapharyngeal and subcutaneous fat tissue thickness were then found.

Results

The conventional measure of body mass index was significantly higher in the snorers (p < 0.05). The difference in the smallest oropharyngeal airway area between snorers and the controls was statistically significant (p < 0.01). The average difference between the largest and the smallest oropharyngeal area in the control group and the snorer group was statistically significant (p < 0.05). There was no significant difference in the largest oropharyngeal airway area, the total subcutaneous fat width and the total parapharyngeal fat width between snorers and control subjects (p > 0.05).

Conclusion

We concluded that the oropharyngeal fat deposition in snorers is not an important factor, and it does not predispose a person to the upper airway narrowing.

Snoring, sleep apnoea and swallowing dysfunction: a videoradiographic study

OBJECTIVES

Snoring is associated with subclinical pharyngeal swallowing dysfunction, probably owing to vibration trauma to the pharyngeal tissues caused by snoring. Negative intrathoracic pressure during apnoea causes stretching of the velum and pharynx. The aim of this study was to investigate whether patients with severe sleep apnoea have an increased frequency of videoradiographically diagnosed subclinical pharyngeal swallowing dysfunction compared with snoring patients with or without mild sleep apnoea as well as with non-snoring controls.

METHODS

Eighty consecutive patients referred for sleep apnoea recordings because of snoring were examined. Fourteen of these patients were excluded because they suffered from dysphagia. Fifteen non-snoring, non-dysphagic volunteers served as controls. Videoradiography was performed to examine the oral and pharyngeal swallowing function in patients and controls. Overnight sleep apnoea recordings were used to evaluate the apnoea-hypopnoea index (AHI).

RESULTS

Pharyngeal swallowing dysfunction was observed in 34/66 (52%) of the snoring patients and in 1/15 (7%) of the non-snoring controls. Pharyngeal swallowing dysfunction was observed in 50% of patients with an AHI of >or=30, in 61% of patients with an AHI of 5-29 and in 43% of patients with an AHI of <5. There was no significant difference in the frequency of pharyngeal swallowing dysfunction between snoring patients with different AHIs.

CONCLUSION

Snoring patients run an increased risk of developing subclinical pharyngeal swallowing dysfunction independent of concomitant sleep apnoea.

Postural variation in oropharyngeal dimensions in subjects with sleep disordered breathing: a cephalometric study

This radiographic study analysed the changes that occurred in the airway and surrounding structures when subjects with sleep disordered breathing moved from the upright to the supine position. Radiographs of 100 dentate, Caucasian males were examined. Fifty individuals were non-apnoeic snorers and in 50 a diagnosis of obstructive sleep apnoea (OSA) had been confirmed by polysomnography. Radiographs were traced and digitized and comparisons were made of the behaviour of the oropharynx, soft palate, tongue, and hyoid between the two groups. When moving from the upright to the supine position, both OSA and snoring subjects showed a similar pattern of change. The antero-posterior dimensions of the oropharyngeal airway decreased highly significantly (P < 0.001) at all levels, with a concomitant reduction in cross-sectional area (P < 0.001). The narrowing was most severe behind the soft palate, where the minimum airway reduced by approximately 40 per cent. Behind the tongue, a 20 per cent decrease was seen. The soft palate showed small but significant increases in area, whilst the tongue altered in shape but not in its overall cross-sectional area. In non-apnoeic snorers only, tongue proportion increased (P < 0.05). At the same time, the hyoid dropped and moved anteriorly, maintaining a constant relationship with the lower border of the mandible. There were no differences between the non-apnoeic snorers and the OSA subjects in any of the postural changes recorded.

Airway assessment by volumetric computed tomography in snorers and subjects with obstructive sleep apnea in a Far-East Asian population (Chinese)

OBJECTIVES

To evaluate the airway dimension of simple snorers and subjects with obstructive sleep apnea (OSA) in a Far-East Asian population (Chinese).

STUDY DESIGN

Prospective study of 117 near-consecutive patients evaluated for snoring and possible OSA from January 1998 to December 1998 in a sleep laboratory. Overnight polysomnography (PSG) was performed on all patients and the sleep parameters, including respiratory disturbance index (RDI), snoring index, minimal oxygen saturation (min O2), percentage of slow wave sleep (SWS), and rapid eye movement (REM) were recorded. Three-dimensional computerized tomography (CT) during awake periods was performed. The anteroposterior (AP) and the lateral distance of the retropalatal (RP) region in the oropharynx, the smallest area of RP, and retroglossal (RG) regions, and the total volume of the oropharynx were measured.

RESULT

Ninety-eight patients were diagnosed with OSA (mean RDI, 41.48 +/- 26.45 events per hour; min O2, 72.82 +/- 12.86%), whereas 19 were simple snorers. The AP and the lateral distance of the RP region, as well as the smallest area of the RP region, are significantly smaller in subjects with OSA. However, no differences in the RG region and the total volume of the oropharynx were found between the two groups. Linear regression analysis demonstrated that the lateral dimension and the smallest RP area in overweight subjects inversely correlated with the RDI, but only the AP dimension of the RP area was found to have an inverse correlation with the RDI in the underweight subjects.

CONCLUSION

In Far-East Asians (Chinese), the RP airway was found to be the primary site of narrowing in subjects with OSA, and the narrowest RP area was inversely correlated with RDI. Furthermore, weight may influence the pattern of RP narrowing by contributing to lateral collapse.

[Changes in the upper airway in patients with sleep obstructive apnea and/or chronic snoring treated with mandibular appliances]

We have analysed the possible modifications in the upper airways (UA) of the lateral cranial teleradiography in 25 adult males with Obstructive Sleep Apnea (OSAS) and/or chronic snoring, with dental and squeletal Class I, treated with advance mandibular appliances (MAD). Results of our study showed a clear increase of the UA in the oropharynx in all the subjects studied. The study of the changes in the UA using the lateral cranial teleradiography in order to evaluate the effectiveness of the MAD can contribute to consider its effectiveness in the cases with OSAS when they are indicated. However it will be needed to contrast these results with polisomnography.

Cephalometric assessment of snoring and nonsnoring children

STUDY OBJECTIVE

To determine the differences in craniofacial cephalometric variables between snoring and nonsnoring children.

DESIGN

Cross-sectional.

SETTING

Case Western Reserve University Dental School, Department of Orthodontics, and local Cleveland orthodontic private practices.

PATIENTS

Twenty-eight snoring and 28 nonsnoring children between the ages of 7 years and 14 years. Nonsnoring subjects were matched to snoring subjects by age, sex, and ethnicity (mean [+/- SD] age, 10+/-2 years; 82% white, 64% female).

INTERVENTIONS

None.

MEASUREMENTS

Snoring was assessed using a sleep behavior questionnaire administered to parents or guardians. The cephalometric radiographs of the study subjects were traced by a single investigator, and 1 angular measurement and 11 linear measurements of hard and soft tissues were recorded. The paired Student's t test was used to analyze the cephalometric data.

RESULTS

Snoring children manifest a significantly narrower anterior-posterior dimension of the pharynx at the superior and most narrow widths. Snoring children also had a greater length from the hyoid to the mandibular plane.

CONCLUSIONS

Snoring children appear to present craniofacial factors that differ from those of nonsnoring children.

Hypersomnia following uvulopalatopharyngoplasty for snoring

This report describes three cases who underwent uvulopalatopharyngoplasty for severe snoring and who subsequently developed progressive excessive daytime sleepiness. All three cases were shown to have sleep fragmentation as a result of non-apnoeic episodic upper airway narrowing. These cases raise the possibility that increased upper airway resistance during sleep may be exacerbated or even caused by uvulopalatopharyngoplasty. Ideally, sleep-disordered breathing should be carefully excluded before this surgery is offered as treatment for severe snoring.

The prevalence of carotid atheromas seen on panoramic radiographs of patients with obstructive sleep apnea and their relation to risk factors for atherosclerosis

PURPOSE

Persons with obstructive sleep apnea syndrome (OSAS) suffer inordinately high rates of stroke, but the cause remains in doubt. Atherosclerosis (atheroma formation) of the extracranial carotid artery has been suggested as a possible cause. Because atheromas can be recognized on panoramic radiographs, this study compared their prevalence in subjects with OSAS and normal controls and analyzed their relation to atherogenic risk factors.

PATIENTS AND METHODS

Panoramic radiographs and medical records of 54 male subjects (mean age, 60.4 years) with OSAS (apnea/hypopnea index [AHI] of 15 or greater and a history of snoring and excessive daytime sleepiness) were assessed for atheromas and risk factors. Age-matched controls were likewise assessed.

RESULTS

Twelve individuals (22%) with OSAS showed atheromas on their radiographs. The radiographs of the controls showed that 3.7% had atheromas. This finding was statistically significant (P = .0079). The prevalence of type 2 diabetes mellitus among individuals with OSAS and atheroma formation (7 of 12 persons, 58%) was far greater than the prevalence of diabetes (10 of 42 persons, 24%) experienced by individuals with OSAS but free of atheroma formation. This finding was also statistically significant (P = .035). The lesions seen in both the subject and control populations were similar and were located in the neck, 1.5 to 2.5 cm inferior-posterior to the angle of the mandible.

CONCLUSIONS

Persons with OSAS are more likely to manifest calcified atheromas on their panoramic radiographs than age-matched controls. Type 2 diabetes is significantly more prevalent in individuals with both OSAS and calcified atheromas.

The prevalence of calcified carotid artery atheromas in patients with obstructive sleep apnea syndrome

PURPOSE

Persons with obstructive sleep apnea syndrome (OSAS) suffer cerebrovascular accidents at three to six times the rate of other Americans. Atherosclerosis of the cervical portion of the carotid artery has been suggested as a possible cause of these strokes. Lateral cephalometric radiographs used to determine the site of upper airway obstruction in sleep apnea patients can also image calcified cervical carotid artery atheromas. However, their prevalence in this group of patients has not been previously reported.

PATIENTS AND METHODS

The radiographs of 47 male subjects (mean age 59.2 years, range 45 to 77 years) diagnosed as having OSAS (apnea/hypopnea index [AHI] of > or = 15 and a history of snoring and excessive daytime sleepiness) were assessed for calcified carotid atheromas. Healthy, age-matched (+/-18 months) controls were likewise assessed.

RESULTS

The radiographs of the subjects with OSAS showed that 21.3% had calcified atheromas. The radiographs of the controls showed that only 2.5% had calcified atheromas. This finding was statistically significant (P = < .000001). The lesions seen in both populations were similar, and located within the soft tissues of the neck at the level of C3 and C4. The lesions were superimposed over these tissues, the prevertebral fascia, and the pharyngeal airspace.

CONCLUSIONS

The results of this study seem to indicate that persons with OSAS have a greater prevalence of calcified carotid artery atheromas than healthy, age-matched persons. These lesions, a possible cause of future stroke, can be detected on lateral cephalometric radiographs.

Upper airway changes in snorers and mild sleep apnea sufferers after uvulopalatopharyngoplasty (UPPP)

OBJECTIVES

We used upper airway (UA) imaging in 20 patients to determine (1) whether an effective enlargement of the UA is obtained after uvulopalatopharyngoplasty (UPPP), and (2) whether UA modifications explain the results of such surgery.

METHODS

Cephalometric measurements were made to assess the posterior airway space, the length and width of the soft palate, and the distance between the hyoid bone and the mandibular plane. Pharyngeal CT measured the airway cross-sectional area (CSA) at each 10-mm slice from 10 mm above (-10) to 40 mm below (+40) the hard palate. Polysomnography was performed before and after surgery (10+/-10 [SD] months). Good responders were defined by an apnea-hypopnea index (AHI) of <10 postsurgery or, in patients in whom AHI was initially <10, a reduction of AHI >50% of the initial AHI.

RESULTS

Twenty patients (age=45+/-11 years) were studied. For the whole group, the mean body mass index (26+/-4 kg/m2) and AHI (14+/-13 vs 18+/-16/h) were unchanged after UPPP. The results of the surgery were mediocre with 7 good responders (35%) and 13 nonresponders (65%) defined by polysomnographic criteria. The only changes on UA imaging for the group as a whole after UPPP were decrease in length (40+/-6 vs 29+/-5 mm, p< or =0.0006) and increase in width of the soft palate (11.5+/-2.7 vs 13.6+/-3.5 mm, p< or =0.006). The increase or decrease in minimal CSA at the oropharyngeal (OP) level after UPPP was significantly correlated with the change in AHI (r=-0.54, p<0.02). Moreover, the changes in CSA obtained at the OP level were significant only in the patients who responded favorably to UPPP (7 vs 13 nonresponders).

CONCLUSIONS

Postoperative OP enlargement is associated with a good outcome of UPPP. Persistent narrowing in nonresponders could be due to the increase in soft palate width after surgery.

The influence of craniofacial structure on obstructive sleep apnea in young adults

PURPOSE

This study compares craniofacial measurements of lateral cephalometric radiographs of young obstructive sleep apnea patients with those of nonapneic snorers and controls.

PATIENTS AND METHODS

Forty-eight patients (BM=28.0+/-3.8) with obstructive sleep apnea, 25 patients (BMI=26.3+/-3.5) with nonapneic snoring, and 54 controls (BMI=24.8+/-2.7) were evaluated. All subjects were between 18 and 40 years of age. Nineteen lateral cephalometric measurements were performed by a single investigator blinded to the results of the polysomnograms.

RESULTS

Univariate logistic regression analysis of the 19 variables showed significantly increased midfacial height (ANS-N), narrowed middle airway space (MAS), steep mandibular plane angle (FMA), elongated pharynx (PNS-Eb), and inferiorly positioned hyoid bone (PNS-H, MP-H) in the obstructive sleep apnea group. The nonapneic snoring group showed only a tendency toward maxillary and mandibular retrognathia (SNA and SNB). No significant differences were found for cranial base angle (S-N-Ba), PAS, inferior airway space, maxillary unit length (ANS-PNS) mandibular unit length (Cd-Gn), tongue height (Tng-Ht), soft palate length (PNS-P), and palatal vault height (Ocl-Pal 6). The OSA group was also found to have multiple sites of abnormality of both the upper and lower pharynx, with 58% of the patients having two or more abnormal values (1 standard deviation from the mean) as opposed to 40% of the nonapneic snoring group.

CONCLUSIONS

Highly significant craniofacial abnormalities were found in the upper and lower pharynx in young obstructive sleep apnea patients. Most of these patients (58%) had abnormalities in both the upper and lower pharynx, suggesting that palatal surgery alone may be an inadequate treatment. This information may define future investigations needed to determine how to more effectively treat this subgroup of young obstructive sleep apnea patients.

[Comparative cephalometric study in patients with obstructive sleep apnea syndrome (OSAS), simple snorers and controls]

Lateral cranial teleradiography was carried out in 106 subjects, including obese and non-obese patients with obstructive sleep apnea syndrome (OSAS) and obese and non-obese healthy snorers and controls. In the OSAS patients alone, the hyoid bone occupied an abnormally low position, which pushed the tongue into a more vertical position. OSAS patients had the most voluminous soft tissues, followed by simple snorers and controls. Soft tissue volume generally was related with obesity. The pharyngeal airway space was widest in controls, intermediate in snores and narrowest in OSAS patients, except in the hypopharynx, where airway dimensions were similar in all the patients studied.

[Orthodontic contribution in sleep apnea]

This study details the role that the orthodontist can play, when faced with sleeping obstructive apneas and snoring phénomena. Of special importance are knowledge of cranio-facial growth, radiographic exam and cephalometric analysis: they mainly help to understand all the aspects of this specific syndrome, and reveal the interest for a neuro-orthodontic or a neuro-surgical orthodontic approach.

Blood flow of the middle cerebral artery with sleep-disordered breathing: correlation with obstructive hypopneas

BACKGROUND AND PURPOSE

Epidemiological data link heavy snoring to an increased risk for stroke, an association often ascribed to hypertension and/or sleep apnea. The aim of this study was to determine whether obstructive hypopneas, central apneas, or obstructive apneas during sleep alter blood flow of the middle cerebral artery (MCA).

METHODS

Doppler sonography of the MCA was performed in conjunction with nightly polysomnography in 11 men and one woman.

RESULTS

A significant decline in blood flow occurred in 76% (169/223) of obstructive hypopneas and in 80% (98/123) of obstructive apneas, compared with only 14% (13/96) of central apneas (P<.0001). While duration of events was not significantly different, MCA blood flow reductions were associated only with the duration of the obstructive hypopneas (P< or =.01) and not with the duration of central (P=.17) or obstructive (P=.07) apneas. The magnitude of fall in arterial oxygen saturation from baseline correlated with a reduced blood flow with obstructive hypopneas but not with obstructive or central apneas.

CONCLUSIONS

With obstructive hypopneas and obstructive apneas, MCA blood flow is more often decreased in comparison to central apneas. MCA blood flow reductions occur with longer obstructive hypopneas and with those hypopneas with greater falls in oxygen saturation. These observations indicate pathophysiology relevant to an increased risk for stroke in heavy snorers and patients with obstructive hypopneas and apneas.

Relationship between body mass index, age and upper airway measurements in snorers and sleep apnoea patients

Anatomical pharyngeal and craniofacial abnormalities have been reported using upper airway imaging in snorers with or without obstructive sleep apnoea (OSA). However, the influences of the age and weight of the patient on these abnormalities remain to be established. The aim of this study was, therefore, to evaluate in a large population of snorers with or without OSA, the relationship between body mass index (BMI), age and upper airway morphology. One hundred and forty patients were referred for assessment of a possible sleep-related breathing disorder and had complete polysomnography, cephalometry and upper airway computed tomography. For the whole population, OSA patients had more upper airway abnormalities than snorers. When subdivided for BMI and age, however, only lean or younger OSA patients were significantly different from snorers as regards their upper airway anatomy. The shape of the oropharynx and hypopharynx changed significantly with BMI both in OSA patients and snorers, being more spherical in the highest BMI group due mainly to a decrease in the transverse axis. On the other hand, older patients (> 63 yrs), whether snorers or apnoeics, had larger upper airways at all pharyngeal levels than the youngest group of patients (< 52 yrs). For the total group of patients, upper airway variables explained 26% of the variance in apnoea/hypopnoea index (AHI), whereas in lean (BMI < 27 kg.m-2) or youngest (age < 52 yrs) subjects upper airway variables explained, respectively 69 and 55% of the variance in AHI. In conclusion, in lean or young subjects, upper airway abnormalities explain a major part of the variance in apnoea/hypopnoea index and are likely to play an important physiopathogenic role. This study also suggests that the shape of the pharyngeal lumen in awake subjects is more dependent on body mass index than on the presence of obstructive sleep apnoea. Further investigation looking at upper airway imaging for surgical selection in obstructive sleep apnoea should focus on lean and young patients.

Videoradiography of patients with habitual snoring and/or sleep apnea. Technical description and presentation of videoradiographic results during sleep concerning occurrence of apnea, type of apnea, and site of obstruction

PURPOSE

The videoradiographic examination described was designed for habitual snorers and sleep apnea syndrome (SAS) patients and was performed during wakefulness and sleep. During wakefulness the purpose was to reveal any dysfunction in deglutition and speech as well as morphologic abnormalities. The purpose during sleep, which usually was induced by low-dose midazolam intravenously, was to reveal the site and form of obstruction in obstructive sleep apnea patients and the site of snoring in habitual snorers.

MATERIAL

The preoperative results of 104 patients are presented. In 57 patients who had apneas, the occurrence and type of apnea could be determined.

RESULTS AND CONCLUSION

A continuous recording over some minutes gave a rough estimate of the degree of SAS and mean duration of apnea. Although much information on SAS can be obtained by this method, it cannot replace polygraphic sleep recording in the investigation of habitual snorers and SAS patients. However, these 2 methods are complementary and can be performed simultaneously as polygraphic videoradiography.

[CT studies on obstructive sleep apnea syndrome]

To ascertain whether there are structural and functional changes in the upper airway of obstructive sleep apnea syndrome (OSAS) pts. We studied 33 pts of OSAS with positive polysomnographic tests, 14 pts of non-apnea snore with negative polysomnographic tests, and 18 normal subject by using CT scanner (Somatom Dr 3). The results are as followings 1. There were narrowing region in the upper airway in OSAS pts and the non-apnea snore pts. Most of the narrowings were located at the level of oropharynx, which was correspondent to the level of the soft palate and the uvula. The length of the soft palate and the pre-spinal soft tissue thickness of two groups of pts were larger than non-snore individual. 2. The pharyngeal compliance was significantly higher in OSAS pts than in non-apnea snore pts. 3. There was no localised deposition of fat tissue surrounding the lumen of upper airway. 4. CT scanning is the non-invasive and more useful procedure for the diagnosis of OSAS and also would help to select the pts for surgery.

Roentgenographic dimensions of the upper airway in snoring patients with and without obstructive sleep apnea

The purpose of this study was to examine whether a simple test, such as routine roentgenographic views of the upper airway, is useful in identifying anatomic narrowing of the airway in patients with sleep apnea. To accomplish this, we prospectively studied a group of 117 patients (95 male and 22 female subjects) referred for evaluation of heavy snoring and possible obstructive sleep apnea. All patients had full nocturnal polysomnography, including measurements of snoring. Lateral view of the airway obtained after swallowing contrast material was used to measure pharyngeal diameters at three sites along the airway. All measurements were performed with the patients standing and supine. We used three different definitions of sleep apnea (apnea/hypopnea index of 10, 20, and 40), and compared airway diameters between the apneic and nonapneic snorers. Only when sleep apnea was defined as greater than 40 apneas plus hypopneas per hour of sleep was there a significant difference in airway diameter at the tip of the palate and 1 cm distal to it between apneic and nonapneic snorers. Both groups of patients demonstrated a significant reduction in the retropalatal distance on assumption of the supine posture. Stepwise, forward, multiple linear regression analysis showed that the retropalatal distance and airway diameter at the tip of the palate and 1 cm distal to it were significant predictors of snoring, but not apnea. We conclude that (1) airway diameters account for some of the variability in snoring, and (2) they do not differentiate between apneic and nonapneic snorers.

Treatment of snoring and obstructive sleep apnea with a dental orthosis

A dental orthosis, designed to increase the size of the upper airway by advancing the mandible, was used in 68 patients to treat snoring and varying degrees of obstructive sleep apnea. The orthosis increased the posterior airway space, as assessed by lateral cephalograms. Seven months (range 2 to 25) after beginning use, 75 percent of patients were using the orthosis regularly. Snoring, by report, was improved in all patients but one (p less than 0.001) and was eliminated in 42 percent (95 percent confidence interval 30 to 55 percent). Sleep quality and sleepiness were also reported improved. Apneas and hypopneas, measured before and after use in 20 patients with obstructive sleep apnea, were reduced from an average of 47 to 20 events per hour (p less than 0.001). Oxygenation and sleep disturbance were also improved. Apnea-hypopnea frequency was reduced with treatment to less than 20/h in 13 patients. Residual frequencies greater than 20/h were associated with higher initial frequencies of apneas and hypopneas. Side effects of orthosis use were minor, and no serious complications were observed. The dental orthosis is an effective treatment for the symptom of snoring and can also effectively treat obstructive sleep apnea of moderate severity.

[Diagnosis value of lateral pharyngeal roentgenography in snoring disease]

In this paper, X-ray findings of the lateral pharynx before uvulopalatopharyngoplasty in 14 cases of snoring disease were studied. The results are as follows. There is less than 5 mm in anterior-posterior airway of pharyngeal cavity (13 cases), and 8 mm (1 case), in diameter. Minimum 2 mm, average 4.4 mm. There is less than 25 mm length of uvula (7 cases), 28-35 mm (7 cases). Minimum 22 mm, average length is 27.9 mm. Shape of uvula is thick and long (12 cases), thick and short 1 case, thin and long 1 case. The etiology, abnormal X-ray finding and X-ray examination of the lateral pharynx, etc. in snoring disease have been discussed.

[Roentgen cinematographic studies in patients who snore]

A radiocinematographic procedure of the pharyngeal examination of snorers is presented. By swallowing, by the production of pharyngeal sounds and by the forced inspiration which produces snoring sounds a dysfunction or an obstruction in the upper respiration tract can be located. This method is a useful diagnostic aid in snoring disease which should precede surgical interventions in the pharynx.