Correlation between cephalometric data and severity of sleep apnea

Two-dimensional facial photography for assessment of craniofacial morphology in sleep breathing disorders: a systematic review

PURPOSE

Craniofacial morphology is integral to Sleep Breathing Disorders (SBD), particularly Obstructive Sleep Apnea (OSA), informing treatment strategies. This review assesses the utility of two-dimensional (2D) photogrammetry in evaluating these metrics among OSA patients.

METHODS

Following PRISMA guidelines, a systematic review was conducted. PubMed, Embase, and Lilacs databases were systematically searched for studies utilizing 2D photography in SBD. Findings were narratively synthesized.

RESULTS

Thirteen studies involving 2,328 patients were included. Significant correlations were found between craniofacial measurements-specifically neck parameters and facial width-and OSA severity, even after BMI adjustment. Ethnic disparities in craniofacial morphology were observed, with photogrammetry effective in predicting OSA in Caucasians and Asians, though data for other ethnicities were limited. Pediatric studies suggest the potential of craniofacial measurements as predictors of childhood OSA, with certain caveats.

CONCLUSION

2D photogrammetry emerges as a practical and non-invasive tool correlating with OSA severity across diverse populations. However, further validation in various ethnic cohorts is essential to enhance the generalizability of these findings.

Relationship between Cephalometric and Ultrasonic Airway Parameters in Adults with High Risk of Obstructive Sleep Apnea

Background/Objectives: Polysomnography and cephalometry have been used for studying obstructive sleep apnea (OSA) etiology. The association between craniofacial skeleton and OSA severity remains controversial. To study OSA's etiology, cephalometry, fiberoptic pharyngoscopy, polysomnography, and sleep endoscopy have been used; however, airway obstructions cannot be located. Recent research suggested ultrasonography for OSA screening and upper airway obstruction localization. Thus, this study aims to investigate the relationship between specific craniofacial cephalometric and ultrasonic airway parameters in adults at high risk of OSA. Methods: To assess craniofacial structure, lateral cephalograms were taken from thirty-three adults over 18 with a STOP-Bang questionnaire score of three or higher and a waist-to-height ratio (WHtR) of 0.5 or higher. Airway parameters were assessed through submental ultrasound. Results: NSBA correlated with tongue base airspace width, while MP-H correlated with oropharynx, tongue base, and epiglottis airspace width. SNA, SNB, and NSBA correlated with tongue width at the oropharynx. At tongue base, ANB and MP-H correlated with tongue width. SNB and NSBA were associated with deep tissue thickness at the oropharynx, while MP-H correlated with superficial tissue thickness at velum and oropharynx. Conclusions: Cephalometric parameters (SNA, SNB, ANB, NSBA, and MP-H) were correlated with ultrasonic parameters in the velum, oropharynx, tongue base, and epiglottis.

The Link between Obstructive Sleep Apnea Syndrome and Cephalometric Assessment of Upper Airways and Hyoid Bone Position

Background and Objectives: To determine whether there are changes in the cephalometric characteristics of the upper airways and hyoid bone, in patients diagnosed with obstructive sleep apnea syndrome (OSAS) compared to a healthy control group. Material and Methods: This retrospective case−control study included 24 patients diagnosed with OSAS (apnea−hypopnea index (AHI) > 5 obtained after polysomnography) and 24 healthy subjects as a control group that completed the STOP-Bang questionnaire to determine whether they had OSAS. Lateral cephalometric examinations were recommended for all these patients. The software used for the cephalogram interpretation was CS 3D Imaging and CS Airway imaging from Carestream Dental. Results: The subjects with OSAS had a smaller superior posterior airway space (SPAS), with an average of 10.32 mm compared to a 12.20 mm mean in the control group (p = 0.03). Patients with OSAS, had a lowered middle airway space (MAS) with a mean of 7.96 mm in the OSAS group and a 10.96 mm mean in the control group (p = 0.00). All the measurements made for the hyoid bone, such as—H-MnP, H-C3, and H-B—showed increased values (means of 26.31 mm, 39.08 mm, 60.05 mm, respectively), for the OSAS group (p = 0.00). Conclusions: Patients suffering from OSAS had reduced dimensions of the SPAS and MAS values. The hyoid bone had a more inferior position in the study group (with increased values for H-MnP, H-C3, and H-B) compared to the control group.

The Interaction of Craniofacial Morphology and Body Mass Index in Obstructive Sleep Apnea

Aim: This study sets out to explore the relationship between craniofacial morphology and obstructive sleep apnea (OSA) severity, assessing the relative contribution of obesity, calculated using BMI. Methods: A sample of 30 adult patients (20 males; 10 females), mean age = 54(±76) years, with a polysomnography-confirmed diagnosis of OSA, i.e., with an apnea-hypopnea index (AHI) of over 5 events/h, was recruited and underwent cephalometric evaluation. Sleep parameters, namely AHI, AHI supine, oxygen desaturation index (ODI), and mean oxygen saturation [Mean SaO2%], were assessed. Correlation analysis between 13 cephalometric features and AHI was performed using a Pearson test. The sample was split into three groups based on AHI score (mild = 10 < AHI < 15; moderate = 15 < AHI < 30; severe = AHI > 30), and ANOVA was performed to compare the means of cephalometric features. In addition, the sample was split into two groups according to BMI (normal weight = BMI < 25; overweight = BMI > 25). Correlation analysis between cephalometric features and AHI was performed for each group using a Pearson test. Results: The average polysomnographic values were AHI = 29.08(±16); AHI supine = 43.45(±21); ODI = 23.98(±21); mean SaO2(%) = 93.12(±2). Posterior facial height (PFH) was significantly lower in the severe OSA group than in patients with moderate OSA (p = 0.05). In the normal-weight group, negative correlations of the PFH and SNA angle with AHI (r = −0.36; r = −0.25, respectively), and positive correlations of the FMA angle and MP-H distance with AHI (r = 0.29; r = 0.20, respectively), were found. In the overweight group, negative correlations of AO-BO distance, SPAS (upper posterior airway space) and PAS (posterior airway space) with AHI (r = −0.30; r = −0.28; r = −0.24, respectively), and positive correlations of AFH (anterior facial height) and the FMA angle with AHI (r = 0.32; r = 0.25, respectively), emerged. Conclusions: PFH seems to be related to the aggravation of OSA. In normal-weight subjects, hard tissue-related factors have a greater impact on OSA severity, whereas in overweight subjects, the impact of fat tissue is greater.

The relationship between three-dimensional craniofacial and upper airway anatomical variables and severity of obstructive sleep apnoea in adults

OBJECTIVE

The aim of this study was to evaluate the relationship between three-dimensional craniofacial and upper airway anatomical variables and severity of obstructive sleep apnoea (OSA) using cone beam computed tomography (CBCT).

METHODS

This was a prospective observational study, consisted of 95 adult OSA whose polysomnography and CBCT were available. Three-dimensional craniofacial and upper airway anatomical analysis were performed using 12 CBCT variables, including sagittal and vertical jaw relationships, maxillary width, the volume, length and minimum axial area of upper airway. The severity of OSA was evaluated through the apnea-hypopnea index (AHI). A hierarchical regression was performed to analyze the relationship between OSA severity and craniofacial and upper airway anatomical variables after controlling patients' demographic characteristics (gender, age, and BMI).

RESULTS

After controlling patients' gender, age, and BMI, individual CBCT variables including MAA, V-RPA, L-RPA and Go-Me were related to AHI. The final hierarchical regression model with demographic variables in Step 1 and CBCT variables (MAA, L-RPA and Go-Me) in Step 2 indicated that CBCT variables added additional explanatory power for AHI (ΔF(3,88) = 5.176, P = 0.002). Among these variables, L-RPA and Go-Me were statistically significant (P < 0.05).

LIMITATION

The OSA severity was expressed by AHI alone.

CONCLUSIONS

Three-dimensional craniofacial and upper airway morphology played an essential role in OSA severity. The most relevant anatomical characteristic with OSA severity were the length of retropalatal airway and mandibular body, which could be used to recognize severe OSA patients and as estimators for selecting the most appropriate treatment modality for OSA patients.

The interaction of obesity and craniofacial deformity in obstructive sleep apnea

OBJECTIVE

Both obesity and craniofacial deformity are important etiologies of obstructive sleep apnea (OSA). The present research aimed to explore their interaction and different impacts on OSA severity.

METHODS

A total of 207 consecutive OSA patients (169 males, 38 females) were included in the research. Based on the body mass index (BMI) value, patients were divided into 77 normal-weight patients (BMI <24 kg m^-2), 105 overweight patients (24 ≤ BMI<28 kg m^-2) and 26 obese patients (BMI ≥28 kg m^-2). All accepted overnight polysomnography and standard lateral cephalogram. Cephalometric measurements involved 25 cephalometric variables. The correlations between these cephalometric variables, BMI and the apnea-hypopnea index (AHI) were evaluated.

RESULTS

For the whole sample after controlling for gender and age, stepwise regression analysis showed that the factors affecting AHI were increased BMI, narrowing posterior airway space, inferior displacement of hyoid and elongation of the tongue. When grouped by BMI, normal-weight group exhibited with more reduced maxillary length and mandible length, and steeper mandible plane than overweight and obese patients (p < 0.0167). Obese group showed least skeletal restriction and most prominent soft tissues enlargement (p < 0.0167). However, these skeletal indexes were not statistically correlated with AHI.

CONCLUSIONS

Obesity and skeletal malformations were both etiological factors of OSA, but obesity seemed to have a greater influence on AHI severity in all kinds of obese and thin OSA patients. Only in normal-weight group, it was affected by both cephalometric variables and BMI.

Cephalometric measures correlate with polysomnography parameters in individuals with midface deficiency

To determine the association between cephalometric measurements and polysomnographic parameters in Brazilian patients with midface deficiency. This was a primary, clinical, observational, longitudinal, retrospective, analytical, and single-center study. Forty-eight patients with midface deficiency were divided into two groups as follows: those who underwent surgically assisted rapid palatal expansion (SARME) and those who received maxillary advancement (MA). Pre- and post-operative cephalometric and polysomnography measurements were obtained. Pearson's correlation was used to verify the presence of any significant associations between PSG scores and cephalometric measurements. Associations between BMI (Body Mass Index) and AHI (Apnea Hypopnea Index) as well as arousals were observed. In the SARME group, associations between AHI and SNA, UAS and MP-H, arousals and SNA, and Co-A and MP-H were noted. Associations between AHI and Co-A, PoOr-A and MP-H, arousals and UAS, and between minimum saturation of O2 and SNA, SNB, and Co-A were observed in the MA group. This study demonstrates the alterations in the middle third of the face that were related to sleep disturbance. In addition, it shows the associations between the polysomnographic parameters and the cephalometric representations corresponding to the analyzed deformities and transverse or anteroposterior maxillary deficiencies.

Evaluation of pharyngeal airway dimensions and hyoid bone position according to craniofacial growth pattern

OBJECTIVE

To compare pharyngeal airway dimensions and hyoid bone position in different craniofacial growth patterns.

METHODS

In total, 611 patients divided into 9 subgroups were compared according to malocclusion classification and vertical growth pattern, and these subgroups were compared in terms of pharyngeal airway and hyoid measurements. A two-way ANOVA test was used to compare the findings of the subgroups.

RESULTS

No significant difference was found for the pharyngeal measurements between the groups (p>0.05). The vertical airway length (PNS-Ep) was significantly shorter in the Class III malocclusion group (p<0.05) and in the hypodivergent group (p<0.05). No statistically significant difference was found between any subgroups in any measurements of the position of the hyoid bone (p>0.05).

CONCLUSION

The pharyngeal airway dimensions and hyoid bone position are similar among individuals in the sagittal direction. The vertical airway length is significantly shorter in Class III and hypodivergent individuals.

Relationship between cephalometric parameters and the apnoea-hypopnoea index in OSA patients: a retrospective cohort study

OBJECTIVE

The purpose of this study was to assess the relationship between cephalometric parameters and apnoea-hypopnoea index (AHI) controlling for the effect of gender, age, and body mass index (BMI) on a large sample of patients with obstructive sleep apnoea (OSA).

METHODS

This retrospective cohort study was conducted on the lateral cephalograms of 253 Caucasian adult OSA patients. Cephalometric analyses were performed using 14 parameters for skeletal and soft tissue morphology, including antero-posterior and vertical jaw relationships, hyoid bone position, soft palate length and thickness, airway space, and tongue length and height. A hierarchical regression was run to examine the amount of variability in AHI that cephalometric variables explained after controlling for patients' general characteristics (gender, age, and BMI).

RESULTS

After controlling for gender, age, and BMI, the increase in AHI variance accounted for by cephalometric parameters was equal to 0.103. Among the cephalometric variables, only MP-H and PNS-P were statistically significant (P < 0.05).

LIMITATIONS

Given the retrospective nature of the study, it is difficult to assess whether other confounding variables not considered in the present study could have influenced the relationship between cephalometric parameters and AHI.

CONCLUSIONS

This study revealed the existence of a relationship between OSA severity and some cephalometric parameters. Indeed soft palate length and vertical position of the hyoid bone were significant predictors of AHI in adult Caucasian OSA patients.

Relations Between Hyoid-Related Cephalometric Measurements and Severity of Obstructive Sleep Apnea

OBJECTIVE

To evaluate the relationship between the hyoid-related cephalometric measurements and the apnea-hypopnea index (AHI) in patients diagnosed with obstructive sleep apnea (OSA).

METHODS

A total of 56 subjects were evaluated by lateral cephalometric radiography and polysomnography (PSG). The OSA diagnosis was made according to the patients' AHI. Included were 13 primary snoring, 16 mild OSA, 10 moderate OSA, and 17 severe OSA. C3-hyoid distance and mentum-hyoid distance were measured on lateral cephalogram. Cephalometric measurements and PSG parameters were compared among the different OSA groups.

RESULTS

The distance between the mentum and hyoid was significantly longer in the severe OSA group than in the primary snoring, mild OSA, and moderate OSA groups (P = 0.029). There was a significant positive correlation between the AHI value and the distance of the mentum hyoid (r = 0.368, P = 0.005). The C3-hyoid distance among the groups was not statistically significant different (P = 0.889).

CONCLUSION

The mentum-hyoid distance of patients with severe OSA was longer compared to the other OSA groups. These patients might have more benefit from the surgeries that have an impact on the position of the hyoid bone compared to other patients with OSA.

The correlation between growth hormone receptor (GHR) polymorphism and obstructive sleep apnea syndrome among the Han and Hani population in China

Obstructive sleep apnea syndrome (OSAS) is a common health problem that is associated with abnormality in craniofacial morphology. The growth hormone receptor (GHR) belongs to the cytokine receptor superfamily and mediates the majority of growth hormone signaling, which, among other functions, determines mandibular growth and development. The aim of this study was to determine if correlations exist between single nucleotide polymorphisms (SNPs) in the GHR gene and OSAS in the Han or Hani ethnic groups in China. A total of 274 Han subjects (106 with OSAS and 168 without OSAS) and a total of 270 Hani subjects (64 with OSAS and 206 without OSAS) were enrolled in our study. Genomic DNA was extracted from peripheral blood obtained from all subjects. Genotyping was undertaken for eight SNPs in the GHR gene (rs3756416, rs7727047, rs2910875, rs12153009, rs2972781, rs12518414, rs4410646, and rs6451620) using PCR amplification and Sanger sequencing. The genotype frequency of rs12518414 was associated with OSAS in both the Han and Hani groups, and the A allele frequency was remarkably lower in Hani OSAS patients compared with Hani controls (16.7 vs 29.9%). In addition, the G allele frequency of the rs3756416 SNP was significantly lower in OSAS patients compared with normal controls in the Hani ethnic group (12.5 vs 24.6%). In a comparison between ethnic groups, genotype frequencies of four SNPs (rs2972781, rs6451620, rs12518414, and rs7727047) differed between Han and Hani OSAS patients, with the A allele frequency of the rs12518414 and G allele frequency of the rs7727047 were significantly higher in the Han OSAS patients. In conclusion, significant associations were detected between some SNPs in the GHR gene and OSAS occurrence while others appeared to be ethnicity-dependent.

A retrospective cephalometric study on upper airway spaces in different facial types

Background

Craniofacial growth pattern has been correlated with variations in size of the upper airway spaces. The objective of this study was to evaluate the nasopharyngeal, oropharyngeal, and hypopharyngeal airway spaces variations according to the craniofacial growth pattern, by comparing brachyfacial, mesofacial, and dolichofacial in Angle Class I individuals.

Methods

To measure the spaces, 45 lateral teleradiographs were used and divided into 3 groups per the craniofacial growth pattern, determined by the Tweed cephalometry angular measurements: FMA and Y-axis. To evaluate the airways, sleep apnea cephalometry was used, containing 28 points that compose 14 factors. Three groups were compared relative to each of the 14 sleep apnea cephalometry measurements. Adherence test to the normal curve was performed. For the non-normally distributed data—measurement of the inferior pharyngeal space—the Kruskal-Wallis test was used for comparison between the groups. For the remaining data, the distribution was normal and ANOVA test was used.

Results

Statistically significant difference was verified among the groups for the measurement of the median posterior-palatal space, with the difference being pointed out by the post hoc test between the brachyfacial and dolichofacial groups. For the other measurements, there was no statistically significant difference.

Conclusions

It could be concluded that there was difference in the median posterior-palatal space measurement, in the oropharynx region, which was reduced for individuals with a dolichofacial pattern.

Craniocervical Posture in Patients with Obstructive Sleep Apnea

INTRODUCTION

Obstructive Sleep Apnea (OSA) is characterized by repeated episodes of upper airway obstruction during sleep.

OBJECTIVE

The objective of this study is to verify the craniofacial characteristics and craniocervical posture of OSA and healthy subjects, determining possible relationships with the apnea/hypopnea index (AHI).

METHODS

This case-control study evaluated 21 subjects with OSA, who comprised the OSA group (OSAG), and 21 healthy subjects, who constituted the control group (CG). Cephalometry analyzed head posture measurements, craniofacial measurements, and air space. Head posture was also assessed by means of photogrammetry.

RESULTS

The groups were homogeneous regarding gender (12 men and 9 women in each group), age (OSAG = 41.86 ± 11.26 years; GC = 41.19 ± 11.20 years), and body mass index (OSAG = 25.65 ± 2.46 kg/m2; CG = 24.72 ± 3.01 kg/m2). We found significant differences between the groups, with lower average pharyngeal space and greater distance between the hyoid bone and the mandibular plane in OSAG, when compared with CG. A positive correlation was found between higher head hyperextension and head anteriorization, with greater severity of OSA as assessed by AHI.

CONCLUSION

OSAG subjects showed changes in craniofacial morphology, with lower average pharyngeal space and greater distance from the hyoid bone to the mandibular plane, as compared with healthy subjects. Moreover, in OSA subjects, the greater the severity of OSA, the greater the head hyperextension and anteriorization.

Lateral teleradiography of the head as a diagnostic tool used to predict obstructive sleep apnea

OBJECTIVES

To (1) assess the relationship between obstructive sleep apnea (OSA) and craniofacial, pharyngeal anatomy and (2) to submit the recommendations for clinicians for increasing the sensitivity in the diagnostics of OSA.

METHODS

A review of the relevant literature linking OSA in adults with cephalometric analysis was performed. In total, 11 articles with similar procedural criteria were selected. The data were analysed using the Comprehensive Meta-Analysis Software (Biostat Inc., Englewood, NJ) and Statistica 12.0 (StatSoft Inc., Dell Software, Tulsa, OK).

RESULTS

Adults with OSA did not show statistically significant differences in the sagittal and vertical skeletal planes in comparison with the controls (p > 0.05). The patients with OSA had soft palate length, width and area increased accordingly by 4.21, 1.99 mm and 0.86 cm(2), tongue area increased by 2.02 cm(2), the upper posterior pharyngeal space (SPAS) and lower posterior pharyngeal space reduced accordingly by 4.53 and 1.32 mm, mandibular plane to the hyoid bone (MP-H) distance increased by 4.14 mm compared with the controls (p < 0.05). The SPAS parameter of the patients with OSA did not show statistically significant differences between the studies, with the mean value being 5.69 mm.

CONCLUSIONS

Analysed cephalometric data totally supported the concept of soft-tissue abnormalities in subjects with OSA, skeletal-only halfway; MP-H and SPAS being the most reliable parameters. Increased MP-H may serve as a predictor when differentiating normal subjects and patients with OSA. Reduced SPAS width could be a prognostic parameter for suspecting OSA. These two values should be kept in mind by dentists and can also be used as a simple auxiliary method by physicians; nevertheless, it is still underestimated and more studies are needed.