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Background: Obstructive sleep apnea (OSA) is the most common sleep-related breathing disorder characterized by repetitive collapse of the upper airway during sleep. However, little evidence is available on the differences between the sub-regions of the upper airway morphology and OSA severity. Since orthodontists frequently perform cone beam computed tomography (CBCT) in the neck area, we aimed to investigate the relationship and the differences between upper airway morphology and OSA severity using CBCT., Materials and Methods: The medical records, CBCT imaging of 21 OSA patients diagnosed by polysomnography, and the apnea-hypopnea index (AHI) results were included to classify OSA severity as mild, moderate, or severe. The minimum cross-sectional areas (MCA) and volumes of the upper pharyngeal airway boundaries in four sub-regions: nasopharynx, retropalatal, retroglossal, and hypopharynx were measured. Dolphin Imaging software was used for upper airway segmentation. The correlation coefficient (r), one-way ANOVA, and the least significant difference post hoc multiple comparison test were applied to fulfill the objectives., Results: A statistically significant relationship was found between the MCA of the nasopharynx and the AHI (r = -0.473, P < 0.05). Furthermore, a difference was found between mild and moderate and moderate and severe OSA severity in the MCA results of the retroglossal region (P < 0.05). However, no relationship was found between the upper airway volume and OSA severity., Conclusions: MCA was moderately negatively correlated to AHI only in the nasopharynx subregion. Moderate OSA presented significantly less MCA than mild and severe OSA only in the oropharynx and retroglossal subregions., (Copyright © 2024 World Federation of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: The objective of this study was to investigate the 2-year postoperative change and influencing factors of the upper airway after mandibular advancement with maxillary setback surgery for patients with a skeletal Class II relationship., Methods: Fifty-seven participants who underwent mandibular advancement with maxillary setback surgery were enrolled consecutively. Cone-beam computed tomography was performed preoperatively, 3 months postoperatively (T1), and 2 years (T2) postoperatively. All parameters were measured using Dolphin Imaging software (Dolphin Imaging and Management Solutions, Chatsworth, Calif)., Results: The total volume (V), minimum cross-sectional area (CSA min ), and glossopharynx increased significantly in both the short-term (V, 13.33%; CSA min , 33.03%; glossopharynx, 26.73%) and long-term (V, 10.19%; CSA min , 23.18%; glossopharynx, 18.27%) after the surgery. Mandibular advancement, mandibular width increase, preoperative CSA min , and body mass index (BMI) significantly affected 2-year postoperative V increases. Mandibular advancement and BMI significantly affected 2-year postoperative glossopharynx increases. Backward movement of point PNS may lead to a reduction of the nasopharynx; however, downward movement of point PNS, upward movement of point A, and increased maxillary width may compensate for this effect by increasing the likelihood of the nasopharynx opening. Furthermore, mandibular body length at T1 is positively associated with relapse rate ([T2 - T1] / T1) of V and CSA min ., Conclusions: Mandibular advancement amount, mandibular width increase, preoperative CSA min , and BMI are the 4 factors for long-term V changes. Patients with a longer mandibular body length might have a lower relapse rate., (Copyright © 2023 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objectives: The medium-term effects of rapid maxillary expansion (RME) on nasal cavity (NC) and upper airway (UA) dimensions based on chronological age are still unclear. This retrospective study evaluated the medium-term changes occurring in the NC and pharyngeal airways (PA) after RME in two distinct age-based cohorts of patients., Methods: This retrospective study included 48 subjects who underwent RME grouped in two cohorts: a 6-9-year-old group (EEG group: early expansion group - 25 subjects) and an 11-14-year-old group (LEG group: late expansion group - 23 subjects). NC and PA volumes were analyzed from CBCT imaging segmentation before RME (T0) and twelve months after RME (T1). The amount of maxillary expansion (PW) and minimal cross-sectional area (CSmin) were also considered., Results: All PAs' volumetric sub-regions, CSmin and PW showed a significant volumetric increment (p < 0.05). Inter-group comparisons showed significant differences (p < 0.05) for nasopharynx and CSmin parameters (p < 0.05), while no significant changes were recorded for the other UA's sub-regions and PW (p > 0.05). According to a deviation analysis, part of the UA increase (more marked for the nasopharynx area) may have occurred due to reduced adenotonsillar tissues, which were larger in the EEG group., Conclusions: Twelve months after treatment, clinicians should not expect changes in the UAs dimensions to be solely related to treatment effects of RME; instead, normal craniofacial growth changes and spontaneous regression of the adenotonsillar tissue could represent the most significant factors influencing UAs changes., Clinical Significance: From the clinical perspective, the results of the present study encourage caution when considering the therapeutic effects of RME on airways dimensions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Introduction: This study aimed to evaluate if there were differences between anterior and posterior anatomic boundaries used for the 3-dimensional determination of pharyngeal airway., Methods: The sample included 150 cone-beam computed tomography scans from healthy patients divided according to (1) age: 6-11, 12-16, and ≥16 years; (2) sex: female and male; (3) anteroposterior skeletal pattern: Class I, II, and III; (4) vertical pattern: brachyfacial, mesofacial, and dolichofacial; and (5) craniocervical inclination (CCI): natural head posture, head flexion, and head extension. Anatomic regions were created to determine the correspondences between structures anteriorly and posteriorly to the pharyngeal airway., Results: The location of the epiglottis, vallecula, hyoid, C2, and C3 were statistically different according to the CCI, and the location of vallecula, C3, and C4 were different according to sex. However, no statistically significant differences were observed between the frequencies of anterior and posterior anatomic region locations among age and different anteroposterior and vertical skeletal patterns. Posterior landmarks tend to be located below the anterior ones; consequently, the anatomic subregion they define will also be located below., Conclusions: Anterior and posterior structures and vertical and anteroposterior skeletal patterns may determine upper airway limits regardless of age. However, the studies must be paired according to sex, and CCI must be standardized., (Copyright © 2023 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objectives: Upper airway assessment requires a fully-automated segmentation system for complete or sub-regional identification. This study aimed to develop a novel Deep Learning (DL) model for accurate segmentation of the upper airway and achieve entire and subregional identification., Methods: Fifty cone-beam computed tomography (CBCT) scans, including 24,502 slices, were labelled as the ground truth by one orthodontist and two otorhinolaryngologists. A novel model, a lightweight multitask network based on the Swin Transformer and U-Net, was built for automatic segmentation of the entire upper airway and subregions. Segmentation performance was evaluated using Precision, Recall, Dice similarity coefficient (DSC) and Intersection over union (IoU). The clinical implications of the precision errors were quantitatively analysed, and comparisons between the AI model and Dolphin software were conducted., Results: Our model achieved good performance with a precision of 85.88-94.25%, recall of 93.74-98.44%, DSC of 90.95-96.29%, IoU of 83.68-92.85% in the overall and subregions of three-dimensional (3D) upper airway, and a precision of 91.22-97.51%, recall of 90.70-97.62%, DSC of 90.92-97.55%, and IoU of 83.41-95.29% in the subregions of two-dimensional (2D) crosssections. Discrepancies in volume and area caused by precision errors did not affect clinical outcomes. Both our AI model and the Dolphin software provided clinically acceptable consistency for pharyngeal airway assessments., Conclusion: The novel DL model not only achieved segmentation of the entire upper airway, including the nasal cavity and subregion identification, but also performed exceptionally well, making it well suited for 3D upper airway assessment from the nasal cavity to the hypopharynx, especially for intricate structures., Clinical Significance: This system provides insights into the aetiology, risk, severity, treatment effect, and prognosis of dentoskeletal deformities and obstructive sleep apnea. It achieves rapid assessment of the entire upper airway and its subregions, making airway management-an integral part of orthodontic treatment, orthognathic surgery, and ENT surgery-easier., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing financial interests or personal relationships that may have influenced the work reported in this study., (Copyright © 2023. Published by Elsevier Ltd.)

Objectives: Orthodontic treatment profoundly impact the pharyngeal airway (PA) of patients. Airway examination is an integral part of daily orthodontic diagnosis, and lateral cephalograms (LC) are reliable to reveal PA structures. This study attempted to develop a simple method to help clinicians make a preliminary judgement of patients' PA conditions and assess the impact of orthodontic treatment on their airways., Methods: LCs of 764 patients were used to train a multistage unit segmentation model. Another 130 images were used to validate the model and more 130 images were used to test the model., Results: Unet was used as the backbone, with a mean dice value of 0.8180, precision of 0.8393, and recall of 0.8188. Furthermore, we identified seven key points and measured related indices. The length of the line separating the nasopharynx and oropharynx and the line separating the oropharynx and hypopharynx were manually measured thrice and the average values was compared. The intraclass correlation coefficient (ICC) for the two lines was 0.599 and 0.855. Then, we performed a single linear regression analysis, which indicated a strong correlation between the predictions and measurements for the two lines., Conclusions: This method is reliable for segmenting three regions (nasopharynx, oropharynx, and hypopharynx) of the PA and calculating related indices. However, the predictions obtained from this model still have errors, and it is necessary for clinical practitioners to assess and adjust the predictions., Clinical Significance: Our model can help orthodontists formulate personalised treatment plans and evaluate the risk of airway stenosis during orthodontic treatment. This method may mark the beginning of a new and simpler approach for PA obstruction detection, specifically tailored to orthodontic patients., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Objectives: To evaluate the accuracy of fully automatic segmentation of pharyngeal volume of interests (VOIs) before and after orthognathic surgery in skeletal Class III patients using a convolutional neural network (CNN) model and to investigate the clinical applicability of artificial intelligence for quantitative evaluation of treatment changes in pharyngeal VOIs., Methods: 310 cone-beam computed tomography (CBCT) images were divided into a training set (n = 150), validation set (n = 40), and test set (n = 120). The test datasets comprised matched pairs of pre- and post-treatment images of 60 skeletal Class III patients (mean age 23.1 ± 5.0 years; ANB<-2⁰) who underwent bimaxillary orthognathic surgery with orthodontic treatment. A 3D U-Net CNNs model was applied for fully automatic segmentation and measurement of subregional pharyngeal volumes of pre-treatment (T0) and post-treatment (T1) scans. The model's accuracy was compared to semi-automatic segmentation outcomes by humans using the dice similarity coefficient (DSC) and volume similarity (VS). The correlation between surgical skeletal changes and model accuracy was obtained., Results: The proposed model achieved high performance of subregional pharyngeal segmentation on both T0 and T1 images, representing a significant T1-T0 difference of DSC only in the nasopharynx. Region-specific differences amongst pharyngeal VOIs, which were observed at T0, disappeared on the T1 images. The decreased DSC of nasopharyngeal segmentation after treatment was weakly correlated with the amount of maxillary advancement. There was no correlation between the mandibular setback amount and model accuracy., Conclusions: The proposed model offers fast and accurate subregional pharyngeal segmentation on both pre-treatment and post-treatment CBCT images in skeletal Class III patients., Clinical Significance: We elucidated the clinical applicability of the CNNs model to quantitatively evaluate subregional pharyngeal changes after surgical-orthodontic treatment, which offers a basis for developing a fully integrated multiclass CNNs model to predict pharyngeal responses after dentoskeletal treatments., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The aim of this study was the development of a statistical model for reliable prediction of Posterior Airway Space (PAS) changes in lateral cephalograms (LCR) of patients after bimaxillary orthognathic surgery. The LCRs of patients who underwent bimaxillary orthognathic surgery were retrospectively analyzed. The anteroposterior dimension of the PAS was measured at three levels in the pre-operative and postoperative LCR: On the nasopharyngeal (SPAS), oropharyngeal (MAS), and hypopharyngeal level (IAS). The data of 139 patients were collected. The following changes of the PAS were measured: in class II patients SPAS: 0.291 mm (SD = 2.570 mm); MAS: 2.444 mm (SD = 2.986 mm); IAS: 0.750 mm (SD = 3.017 mm); in class III patients SPAS: 1.377 mm (SD 3.212 mm); MAS: 0.962 (SD: = 3.135 mm); IAS: 0.370 mm (SD = 3.468 mm). Linear regression analysis showed for class II patients, a significant influence of mandibular movement on MAS (p = 0.049) and a significant effect of maxillary and mandibular movements on SPAS (p = 0.001) and MAS (p = 0.022) in class III patients. The other jaw displacements had no significant impact on the investigated PAS levels. While the presented method does not permit exact prediction of the dimension of the PAS, it is still an easily accessible method of orientation for the surgeon. The surgeon can initiate three-dimensional examinations to provide exact three-dimensional prediction based on this calculation., Competing Interests: Declaration of competing interest The authors declare to have no conflict of interest., (Copyright © 2022 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

The aim of this study was to retrospectively evaluate pharyngeal airway (PA) changes after bimaxillary surgery (BMS). Preoperative, immediate- and 5-year postoperative cone-beam computed tomography images of subjects who underwent BMS were assessed. The primary outcome variable was the PA volume. The secondary outcome variables were the retropalatal and oropharyngeal volumes, cross-sectional area, minimal hydraulic diameter, soft tissue, skeletal movements and sleep-disordered breathing (SDB). A total of 50 patients were included, 33 female and 17 male, with a mean age of 26.5 years. A significant increase in the PA volume was seen immediately after surgery (40%), and this increase was still present at 5-year follow-up (34%) (P < 0.001). A linear mixed model regression analysis revealed that a mandibular advancement of ≥5 mm (P = 0.025) and every 1-mm upward movement of epiglottis (P = 0.016) was associated with a volume increase of the oropharyngeal compartment. Moreover, ≥5-mm upward movement of hyoid bone (P = 0.034) and every 1-mm increase in minimal hydraulic diameter (P < 0.001) correlated with an increase of the PA volume. A total of 30 subjects reported improvement in the SDB at 5-year follow-up. This study demonstrated that BMS led to an increase in PA dimensions in non-OSA patients, and these changes were still present at 5-year follow-up. BMS seemed to induce clinical improvement in SDB., Competing Interests: Declaration of competing interest All authors have no competing interests to declare., (Copyright © 2022. Published by Elsevier Ltd.)

Introduction: The pharyngeal airway is important during diagnosis and treatment planning in orthodontics. This study aimed to compare the changes in the shape of the pharyngeal airway in patients with Class III malocclusion treated with a facemask (FM) with a removable maxillary appliance and modified tandem traction bow appliance (MTTBA)., Methods: This study consisted of pretreatment and posttreatment lateral cephalograms of 35 subjects with skeletal and dental Class III malocclusion. In the first group, 20 patients (12 males, 8 females; mean age, 10.2 years) were treated with MTTBA. The mean treatment time was 12 months. In the second group, 15 patients (10 males, 5 females; mean age, 10.3 years) were treated with FM. The mean treatment time was 11.7 months. Nineteen pharyngeal landmarks were considered from the image corresponding to the midsagittal plane and marked using tpsDig software (version 2.04; Stony Brook, NY). Pharyngeal airway shape difference between the groups was assessed by performing a Generalized Procrustes analysis. The shape deformation of the pharyngeal airway from the pre- to posttreatment periods was evaluated using the thin-plate spline method., Results: There were no differences between MTTBA and FM groups according to airway shape for pretreatment and posttreatment periods. However, there were some deformities using the enlargement of the nasopharyngeal area in the FM group and oropharyngeal area in the MTTBA group according to pretreatment periods., Conclusions: There were no differences between the groups according to the mean pharyngeal airway shapes when the posttreatment periods of the FM and MTTBA groups were examined., (Copyright © 2022. Published by Elsevier Inc.)

Introduction: This study aimed to evaluate a 3-dimensional (3D) U-Net-based convolutional neural networks model for the fully automatic segmentation of regional pharyngeal volume of interests (VOIs) in cone-beam computed tomography scans to compare the accuracy of the model performance across different skeletal patterns presenting with various pharyngeal dimensions., Methods: Two-hundred sixteen cone-beam computed tomography scans of adult patients were randomly divided into training (n = 100), validation (n = 16), and test (n = 100) datasets. We trained the 3D U-Net model for fully automatic segmentation of pharyngeal VOIs and their measurements: nasopharyngeal, velopharyngeal, glossopharyngeal, and hypopharyngeal sections as well as total pharyngeal airway space (PAS). The test datasets were subdivided according to the sagittal and vertical skeletal patterns. The segmentation performance was assessed by dice similarity coefficient, volumetric similarity, precision, and recall values, compared with the ground truth created by 1 expert's manual processing using semiautomatic software., Results: The proposed model achieved highly accurate performance, showing a mean dice similarity coefficient of 0.928 ± 0.023, the volumetric similarity of 0.928 ± 0.023, precision of 0.925 ± 0.030, and recall of 0.921 ± 0.029 for total PAS segmentation. The performance showed region-specific differences, revealing lower accuracy in the glossopharyngeal and hypopharyngeal sections than in the upper sections (P <0.001). However, the accuracy of model performance at each pharyngeal VOI showed no significant difference according to sagittal or vertical skeletal patterns., Conclusions: The 3D-convolutional neural network performance for region-specific PAS analysis is promising to substitute for laborious and time-consuming manual analysis in every skeletal and pharyngeal pattern., (Copyright © 2022 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: The study aimed to evaluate the morphologic changes in the pharyngeal airway after bimaxillary surgery in skeletal Class III malocclusion patients with or without asymmetry. We also analyzed the correlation between positional changes in the menton, hyoid bone, and changes in the dimensions of the pharyngeal airway., Methods: We included 32 patients with skeletal Class III malocclusion who underwent bimaxillary surgery. There were 16 subjects in the symmetry group (10 male, 6 female; mean age, 22.44 ± 5.14 years), and 16 in the asymmetry group (10 male, 6 female; mean age, 21.38 ± 4.62 years). Preoperative and postoperative (2 months after surgery) cone-beam computed tomography scans were taken and then analyzed by comparing postoperative changes in each group., Results: The anteroposterior lengths at the uvula level (P2L) and epiglottis level (P3L) were significantly decreased in the symmetry group. The P2L was also significantly decreased in the asymmetry group, and a difference in the P3L was observed. However, there was no significant change in the width at the uvula level (P2W) and epiglottis level (P3W) in the symmetry group. In contrast, in the asymmetry group, P2W and P3W were significantly decreased. The cross-sectional ratio was significantly decreased P2 (P2L/P2W) and P3 (P3L/P3W) in the symmetry group. However, a statistically significant decrease occurred only at P3 in the asymmetry group. Anteroposterior positional changes of the menton and P2L (r = -0.370; P <.05), P3L (r = -0.414; P <0.05), and P3L/P3W (r = -0.361; P <0.05) were correlated., Conclusions: Differences in the morphologic features of the pharyngeal airway after bimaxillary surgery was observed in both the symmetry and asymmetry groups. Bimaxillary surgery with a mandibular setback in patients with skeletal Class III malocclusion worsened morbidity of the elliptical structure of the pharyngeal airway. However, it worsened less in the asymmetry group than in the symmetry group., (Copyright © 2022. Published by Elsevier Inc.)

Introduction: Although it is well known that orthognathic surgery modifies the upper airways, it is still unclear which are the determining factors to achieve adequate and predictable results in all the patients regardless of the initial malocclusion type and satisfying all the traditional orthognathic treatment objectives. This study aimed to correlate airway changes with surgical movements and other variables and the planning modalities to better understand how to control airway dimensions with treatment., Methods: This study involved 61 patients requiring bimaxillary surgery to correct various dentoskeletal deformities without a history of obstructive sleep apnea syndrome. In all the subjects, the orthosurgical treatment was planned according to the same treatment principles and regardless of the initial airway dimension. The 3-dimensional volume and minimal axial area values generated by cone-beam computed tomography at the preoperative, 3-week, and 1-year postoperative controls were evaluated and correlated with surgical movements and other variables., Results: Although the planning did not consider the initial size of the airways, a significant increase was found for volume and minimal axial area in both the short term (volume, 29.0%; area, 51.2%) and long term (volume, 18.2%; area, 39.8%) with no regard to the type of malocclusion. Only 3 of the variables examined were found to significantly affect the airway: the preoperative dimensions, gender, and the extent of mandibular advancement. These 3 explanatory variables combined can predict the 1-year postoperative volume and minimal area with an accuracy of 71% and 44%, respectively., Conclusions: According to this study, orthosurgical treatment can protect airways from unexpected unfavorable changes and satisfy the other treatment goals regardless of the initial malocclusion as long as the facial deformities are properly addressed for each patient. Furthermore, these results identified 3 main variables that influence postoperative airways dimensions the most. Keeping in mind that the relationship between airway dimensions and obstructive sleep apnea syndrome is not clearly explained, these considerations may prove to be a useful tool to help in preventing and managing this disease. Studies involving larger samples of patients and evaluating more variables are mandatory to better understand the correlation between airways and sleep function., (Copyright © 2022 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: The objective of this study was to investigate the morphological changes of the upper airway and the position of the hyoid bone in hyperdivergent adults with different mandibular lengths after premolar extraction., Materials: The data of 57 hyperdivergent adults, aged 20-35 years, who had 4 premolar extractions were included for the study. Mandibular length (CoGn) was used for grouping (A: long CoGn, B: short CoGn). Pretreatment and posttreatment lateral cephalograms and cone-beam computed tomography images were used to assess the position of mandible, hyoid bone, and upper airway using paired t test. An independent sample t test was used to detect changes of the airway and hyoid position between groups A and B. Pearson correlation analysis was applied to estimate the correlation between pharyngeal spaces and dentoskeletal morphology at P <0.05., Results: In all subjects, we observed retraction of the upper incisors, mesial movement of the lower molars, and reduction of the mandibular planes. In group A, differences were found in anterior and posterior movements of the hyoid bone, increase of airway volume, minimum cross-sectional area (MCA) and anteroposterior linear distance (APL) (P <0.05). There were notable differences in the change of hyoid position, airway volume, MCA, and APL between group A and group B. Glossopharyngeal and hypopharyngeal volumes, MCA, and APL were correlated with articular angle, mandibular plane, and hyoid bone position (P <0.05)., Conclusions: With a comprehensive diagnosis and treatment, premolar extraction in hyperdivergent adults with favorable CoGn can facilitate improvement of esthetics, hyoid bone position, and the increase in glossopharyngeal and hypopharyngeal volumes and MCA., (Copyright © 2021 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: The objective of this research was to evaluate the effect of orthodontic extraction on the pharyngeal airway volume and Minimum cross-sectional area (MCA) in growing and adult patients., Methods: Seven databases, unpublished gray literature, and the references list of the identified articles were electronically searched for relevant studies that met our eligibility criteria. Included studies assessed the effect of dental extraction or sagittal dental movements on pharyngeal airway dimensions. The quality of the included studies was assessed using the methodological index for nonrandomized studies. In addition, a meta-analysis was conducted using the RevMan 5 (Nordic Cochrane Centre, Cochrane Collaboration, Copenhagen, Denmark)., Results: In 7 studies, 268 treated patients with a mean age of 19.1 ± 7.6 years and 342 nonextraction control group subjects with a mean age of 19.3 ± 7.2 years were included. Compared with the control group, no statistically significant difference was found in total, nasopharyngeal, glossopharyngeal, oropharyngeal volume, or MCA (P >0.05) in the extraction group except in oropharyngeal volume in which a statistically significant increase in the volume 0.41 cm 3 (95% CI, 0.05-0.80; P = 0.03) was detected. The clinical significance of this increase is questionable. Included studies showed a moderate to high risk of bias., Conclusions: There is no strong evidence to support the concept that premolar extractions in bimaxillary protrusion or crowded growing and adult patients reduce either pharyngeal airway volume or MCA. Moreover, as the level of evidence was considered very low for all variables, the magnitude, and direction of the summaries have to be interpreted with caution. Future studies with better quality could significantly affect the direction and strength of the results., Trial Registration Number: PROSPERO CRD42018089924., (Copyright © 2021 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: The purpose of this study was to assess the stability of changes in the upper airways 4 years after orthognathic surgery in patients with skeletal Class II malocclusion., Methods: A retrospective clinical study was conducted including 33 cone-beam computed tomography images from 11 patients (average age of 35.91 years) followed up longitudinally for 4 years. The airways were measured with the help of the Dolphin Imaging software (Dolphin Imaging and Management Systems, Chatsworth, Calif) at 3 points: T1 (preoperative), T2 (6 months after surgery), and T3 (4 years after surgery). The parameters assessed were surface area (SA), minimum axial area, and volume (VOL) of the pharyngeal airway space. The times were compared using analysis of variance and Tukey's test. Pearson's analysis was performed to assess the correlation with surgical changes and age (P <0.05)., Results: Four years after operating on the airway spaces, the means of SA and VOL were significantly higher than those observed before the surgery (P <0.05). The means at 6 months were intermediate, with no significant difference before the surgery and 4 years after it (P >0.05). There was no significant correlation of the changes in SA, VOL, and minimum axial area with the amount of mandibular advancement, counterclockwise rotation of the occlusal plane, and age of the patient (P >0.05)., Conclusions: Four years after mandibular advancement surgery in patients with skeletal Class II malocclusion, the increases in the airways remained stable., (Copyright © 2021 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: This study aimed to test the accuracy of a new automatic deep learning-based approach on the basis of convolutional neural networks (CNN) for fully automatic segmentation of the sinonasal cavity and the pharyngeal airway from cone-beam computed tomography (CBCT) scans., Methods: Forty CBCT scans from healthy patients (20 women and 20 men; mean age, 23.37 ± 3.34 years) were collected, and manual segmentation of the sinonasal cavity and pharyngeal subregions were carried out by using Mimics software (version 20.0; Materialise, Leuven, Belgium). Twenty CBCT scans from the total sample were randomly selected and used for training the artificial intelligence model file. The remaining 20 CBCT segmentation masks were used to test the accuracy of the CNN fully automatic method by comparing the segmentation volumes of the 3-dimensional models obtained with automatic and manual segmentations. The accuracy of the CNN-based method was also assessed by using the Dice score coefficient and by the surface-to-surface matching technique. The intraclass correlation coefficient and Dahlberg's formula were used to test the intraobserver reliability and method error, respectively. Independent Student t test was used for between-groups volumetric comparison., Results: Measurements were highly correlated with an intraclass correlation coefficient value of 0.921, whereas the method error was 0.31 mm 3 . A mean difference of 1.93 ± 0.73 cm 3 was found between the methodologies, but it was not statistically significant (P >0.05). The mean matching percentage detected was 85.35 ± 2.59 (tolerance 0.5 mm) and 93.44 ± 2.54 (tolerance 1.0 mm). The differences, measured as the Dice score coefficient in percentage, between the assessments done with both methods were 3.3% and 5.8%, respectively., Conclusions: The new deep learning-based method for automated segmentation of the sinonasal cavity and the pharyngeal airway in CBCT scans is accurate and performs equally well as an experienced image reader., (Copyright © 2021. Published by Elsevier Inc.)

Introduction: The purpose of this cross-sectional retrospective study was to evaluate the patterns of pharyngeal airway volume change determined by cervical vertebral maturation (CVM) stage and compare it with that which was characterized by chronological age. Correlations between hyoid bone positions and airway volumes were also examined., Methods: CVM staging was determined from cone-beam computed tomography scans of 420 white patients aged 9-15 years. Patients were stratified on the basis of sex and skeletal pattern to establish pharyngeal airway volume clusters for each CVM stage. The horizontal and vertical positions of hyoid bones were measured using Hyoidius and Sella., Results: Males had larger pharyngeal airway volumes compared with females. In males, the largest increases in pharyngeal airway volumes occurred at an earlier CVM stage than females. No statistically significant differences in pharyngeal airway volumes were noted in subjects with skeletal Class I, II, and III malocclusion. The hyoid bone in males was more anteriorly and inferiorly positioned compared with females. The Class III group had a further forward position of the hyoid bone than the Class I and II groups., Conclusions: The patterns of pharyngeal airway change obtained using CVM staging did not correlate well with traditional maturational models for skeletal growth. It implies that chronologic age could be a relatively reliable indicator for the assessment of pharyngeal airway volumes in adolescents, as outlined in part 1 of the present study. Subjects with anteriorly and superiorly positioned hyoid bones exhibited smaller pharyngeal airway volumes, which highlights the role of soft tissue and its influence on airway patency., (Copyright © 2021 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: The objective of this research was to observe changes in aerodynamics and anatomic characteristics of the upper airway after mini-implants assisted rapid maxillary expansion and to evaluate the correlation between the 2 changes of the upper airway in young adults., Methods: Thirty consecutive patients (mean age, 23.82 ± 3.90 years; median, 24.5 years; 9 males, 21 females) were involved. Cone-beam computed tomography was taken before activation and over 3 months. Three-dimensional models of the upper airway were reconstructed on the basis of cone-beam computed tomography. The anatomic characteristics of the upper airway, including volume, area, transverse, and sagittal diameter, were measured. The aerodynamic characteristics of the upper airway were calculated on the basis of 3-dimensional models using computational fluid dynamics. The correlation between the changes in aerodynamics and anatomic characteristics of the upper airway was explored., Results: The enlargements of the volume of the total pharynx, nasopharynx, and oropharynx were found (9.99%, 20.7%, and 8.84%, respectively). The minimum cross-sectional area increased significantly (13.6%). The airway resistance (R) and maximum velocity (V max ) decreased significantly in both the inspiration and expiration phase (inspiration: R, -26.8%, V max , -15.7%; expiration: R, -24.7%, V max , -16.5%). The minimum wall shear stress reduced significantly only in the inspiration phase (-26.3%). The correlations between decreased R and increased volume and minimum cross-sectional area were observed., Conclusions: Mini-implants assisted rapid maxillary expansion is an effective device for improving anatomic characteristics represented by the total volume of the upper airway and minimum cross-sectional area, which contributed to the respiratory function depending on the favorable changes of aerodynamic characteristics including resistance, velocity, and minimum wall shear stress., (Copyright © 2021 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: This study aimed to compare cephalometrically the pharyngeal airway, hyoid bone, and soft palate (SP) changes after Class II malocclusion treatments using Twin-block (TWB) and Forsus Fatigue Resistant Device (FFRD) (3M Unitek Corp, 3M Dental Products, Monrovia, Calif) during the postpeak growth period., Methods: Forty-two patients with Class II malocclusion treated during the postpeak growth period were randomly and retrospectively included in this study. These patients were divided into 2 treatment groups: TWB and FFRD. The skeletal, dental, pharyngeal airway, hyoid bone position, and SP measurements were obtained from the lateral cephalometric radiographs taken at the beginning and at the end of the treatment. Paired-samples and independent-samples t tests were used for the intragroup and intergroup comparisons, respectively., Results: In the TWB group, the SNB (°), Md1-NB (mm), Md1-NB (°), and McNamara upper and lower pharyngeal airway dimensions significantly increased, whereas the ANB (°), AD1-Ba (mm), AD2-H (mm), adenoidal nasopharyngeal area, and SP angle decreased (P < 0.05). In the FFRD group, the SNB (°), Md1-NB (mm), Md1-NB (°), Ptm-Ba (mm), and McNamara upper airway dimensions significantly increased, whereas the ANB (°), AD2-H (mm), and interincisor angle decreased (P < 0.05). Moreover, there were statistically significant differences in the Md1-NB angles and SP thicknesses between the 2 groups (P < 0.05)., Conclusions: The effects of TWB and FFRD treatment on the airway during the postpeak growth period were similar. However, the FFRD caused a greater mandibular incisor protrusion., (Copyright © 2020 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

The aim of this study was to evaluate volumetric changes of the posterior airway space (PAS) following bimaxillary surgery using a high oblique sagittal split osteotomy (HSSO) of the mandibular ramus. The cone beam CTs of Class II and Class III patients taken before (T0) and 6-12 months after surgery (T1) were analyzed using 3D software (Mimics® Innovation Suite 18.0). The PAS was divided into three segments (superior, middle, inferior) by three planes parallel to the Frankfurt horizontal plane intersecting at the posterior nasal spine, the velum palatinum and the epiglottis. Total (TPAS) and partial volumes (SPAS = superior, MPAS = middle, IPAS = inferior) were calculated. For the 25 Class II patients, a highly significant increase (p<0.001) of the total, middle and inferior airway space (TPAS: +33.6%, MPAS: +43.1%, IPAS: +55.9%) was found, while the increase of the upper airway space was statistically not significant (+5.4%, p = 0.074). For the 28 Class III patients, the total, middle and inferior airway space increased statistically insignificantly (TPAS: +4.6%, p = 0.265, MPAS: +2.7%, p = 0.387, IPAS: +2.8%, p = 0.495), while the increase of the upper airway space was statistically significant (+9.7%, p = 0.010). Bimaxillary orthognathic surgery using the HSSO technique led to a significant increase of PAS for Class II patients and could conserve the PAS for Class III patients., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors., (Copyright © 2021 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Introduction: This study investigated correlations between airway size and age, sex, and skeletal patterns; identified airway change trends; and measured volumetric norms in children via cone-beam computed tomography., Methods: Four hundred twenty nontreated white patients were stratified by age, sex, and anteroposterior skeletal pattern. The nasopharyngeal airway (NPA), oropharyngeal airway (OPA), and total pharyngeal airway (TPA) volumes were delineated on 3-dimensional digital cephalograms. SPSS (SPSS, Chicago, Ill) was used to run an analysis of variance and post-hoc analyses., Results: The Class III group had significantly larger OPA volumes than Class I and II groups. Male subjects had considerably larger NPA volumes than female subjects. Age was significantly associated with all 3 airway volumes (P <0.05). The young cohort (ages, 9-10 years) had a mean TPA of 11,435.34 ± 484.45 mm 3 , the middle cohort (ages, 11-13 years) had a mean TPA of 14,152.07 ± 395.46 mm 3 , and the older cohort (ages, 14-15 years) had a mean TPA of 18,057.99 ± 484.25 mm 3 ., Conclusions: An effect of skeletal classification on OPA and a sex effect on NPA were observed. The annual change in the mean of TPA volume decreased in subjects aged 10-12 years, then rebounded until 14 years. TPA change peaked in female subjects 1 year before male subjects., (Copyright © 2020 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: This study aimed to evaluate the follow-up observation of patients with obstructive sleep apnea treated with maxillomandibular advancement (MMA) procedure with or without genial tubercle advancement (GTA)., Methods: A total of 25 patients (mean age 37.1 ± 17.3 years) were included in the study. Cone-beam computed tomography scans were taken before treatment; after presurgical orthodontic treatment; immediately after MMA procedure; and follow-up visit. All Digital Imaging and Communications in Medicine files were analyzed using the Dolphin 3D Imaging software program (Dolphin Imaging and Management Solutions, Chatsworth, Calif) to determine the total airway volume (TAV), airway area (AA), and minimal cross-sectional area (MCA). Dolphin 3D voxel-based superimposition was used to determine the amount of skeletal advancement with MMA and changes after surgery., Results: Significant increase in TAV, AA, and MCA was found with MMA treatment (40.6%, 28.8%, and 56.4%, respectively, P <0.0001). Smaller but significant decrease in TAV, AA, and MCA was found during a follow-up visit (20.0%, 9.7%, and 26.8%, respectively, P <0.0001) giving a net increase of TAV, AA and MCA (35.8%, 27.1%, and 45.9%, respectively). No significant differences were found in any of the airway measurements with or without the GTA procedure. The average forward movements of the maxilla, mandible, and chin were 6.6 mm, 8.2 mm, and 11.4 mm, respectively. A relapse of less than 1 mm was found in each of the variables during the follow-up period. No correlation was found between the magnitudes of skeletal advancement and the change in oropharyngeal airway space (OPAS)., Conclusions: Significant increase in OPAS can be expected with MMA surgery with or without GTA procedure in patients diagnosed with obstructive sleep apnea. A partial loss in OPAS was found during the follow-up visit. The surgical movements were found to be stable, with less than 1 mm of relapse during the follow-up period, which was not clinically significant., (Copyright © 2020. Published by Elsevier Inc.)

Purpose: Severe pharyngitis is frequently associated with inflammations caused by streptococcal pharyngitis, which can cause immune-mediated and post-infectious complications. The recent global pandemic of coronavirus disease (COVID-19) encourages the use of telemedicine for patients with respiratory symptoms. This study, therefore, purposes automated detection of severe pharyngitis using a deep learning framework with self-taken throat images., Methods: A dataset composed of two classes of 131 throat images with pharyngitis and 208 normal throat images was collected. Before the training classifier, we constructed a cycle consistency generative adversarial network (CycleGAN) to augment the training dataset. The ResNet50, Inception-v3, and MobileNet-v2 architectures were trained with transfer learning and validated using a randomly selected test dataset. The performance of the models was evaluated based on the accuracy and area under the receiver operating characteristic curve (ROC-AUC)., Results: The CycleGAN-based synthetic images reflected the pragmatic characteristic features of pharyngitis. Using the synthetic throat images, the deep learning model demonstrated a significant improvement in the accuracy of the pharyngitis diagnosis. ResNet50 with GAN-based augmentation showed the best ROC-AUC of 0.988 for pharyngitis detection in the test dataset. In the 4-fold cross-validation using the ResNet50, the highest detection accuracy and ROC-AUC achieved were 95.3% and 0.992, respectively., Conclusion: The deep learning model for smartphone-based pharyngitis screening allows fast identification of severe pharyngitis with a potential of the timely diagnosis of pharyngitis. In the recent pandemic of COVID-19, this framework will help patients with upper respiratory symptoms to improve convenience in diagnosis and reduce transmission., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Durophagous fish consume a diet based primarily on hard-shelled animals, mainly mollusks. In order to successfully perform this task, they are equipped with an extra set of jaws located in their throat called pharyngeal jaws. Here we present the results of a study of the structure of the bony material of the exceptionally powerful lower pharyngeal jaws (LPJs) of the black drum Pogonias cromis which generate the highest biting forces documented in bony fishes. In particular, we studied the two long and slender struts that support the entire dental plate and teeth of the LPJ, in order to determine how this structure withstands the huge stresses it encounters repetitively and for long periods of time. We describe the hierarchical structure of the struts of lower pharyngeal jaw of P. cromis at a wide range of length scales, and show how it is adapted to successfully achieve its high mechanical performance. In particular, we show that the bone material of the strut is neither cortical nor cancellous, and although it is highly porous, its complex and layered three-dimensional arrangement of thick lamellae sheets, which are inter-connected by thin plates, is perfectly tailored to withstand extremely large but directionally-consistent forces. STATEMENT OF SIGNIFICANCE: The diet of some fish consists of hard food, like mollusks and shells. In order to accomplish the task of cracking this type of food, they have an extra set of bony jaws located in their throat, called pharyngeal jaws. Here we describe the hierarchical structural elements of these jaws which allow them to withstand huge forces repeatedly over long periods of time. Surprisingly, the structure is very porous, but its architectural design is superbly adapted to handle consistently-oriented forces. This structural motif defines a new bony material which is neither cortical nor cancellous., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier Ltd.)

Background: Schwannomas encompassing the superior parapharyngeal space are challenging lesions because of the anatomical complexity of this region and the frequent involvement of the neurovascular structures of the jugular foramen. The purpose of this study is to report the technical aspects and the advantages of the anterolateral approach, here proposed for schwannomas of this complex area., Methods: The main steps of the anterolateral approach are described in detail, along with the results of a consecutive series of 38 patients with a retrostyloid superior parapharyngeal schwannoma involving the jugular foramen operated on by means of this route between 1999 and 2019., Results: The supine position is generally preferred. The medial border of the sternocleidomastoid muscle, mastoid tip, and superior nuchal line are the landmarks for the hockey-stick skin incision. The accessory nerve is retrieved and mobilized cranially. Detachment of the sternocleidomastoid, digastric, and nuchal muscles allows for a 180° exposure of the extracranial side of the jugular foramen. Three working corridors, namely the pre-carotid, pre-jugular, and retro-jugular, allow access to the deeper part of the jugular foramen area and the superior parapharyngeal space. In the present series, a gross total resection was achieved in 89.4% of the patients. Three recurrences occurred after an average follow-up of 80.5 ± 51 months., Conclusions: The anterolateral approach is highly effective in the treatment of retrostyloid superior parapharyngeal space schwannomas involving the jugular foramen. Its simplicity of execution, versatility, and very low morbidity are among its main strengths., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objectives: The aim of this study was to investigate whether quantitative CT image-biomarkers (IBMs) can improve the prediction models with only classical prognostic factors for local-control (LC), regional-control (RC), distant metastasis-free survival (DMFS) and disease-free survival (DFS) for head and neck cancer (HNC) patients., Materials and Methods: The cohort included 240 and 204 HNC patients in the training and validation analysis, respectively. Clinical variables were scored prospectively and IBMs of the primary tumor and lymph nodes were extracted from planning CT-images. Clinical, IBM and combined models were created from multivariable Cox proportional-hazard analyses based on clinical features, IBMs, and both for LC, RC, DMFS and DFS., Results: Clinical variables identified in the multivariable analysis included tumor-site, WHO performance-score, tumor-stage and age. Bounding-box-volume describing the tumor volume and irregular shape, IBM correlation representing radiological heterogeneity, and LN&#95;major-axis-length showing the distance between lymph nodes were included in the IBM models. The performance of IBM LC, RC, DMFS and DFS models (c-index(validated):0.62, 0.80, 0.68 and 0.65) were comparable to that of the clinical models (0.62, 0.76, 0.70 and 0.66). The combined DFS model (0.70) including clinical features and IBMs performed significantly better than the clinical model. Patients stratified with the combined models revealed larger differences between risk groups in the validation cohort than with clinical models for LC, RC and DFS. For DMFS, the differences were similar to the clinical model., Conclusion: For prediction of HNC treatment outcomes, image-biomarkers performed as good as or slightly better than clinical variables., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Introduction: Pharyngeal airway space (PAS) assessment has been used in the past for a better understanding of orthodontic and surgical outcomes; however, this analysis could be unreliable. Our objective was to evaluate possible changes in the PAS reading in the same patient from their consecutive cone-beam computed tomography (CBCT) scans., Methods: We evaluated a total of 27 patients' CBCT scans obtained at 2 time points with the use of a standardized acquisition protocol. The mean age at T0 was 31 years (range 17-62 years) and the follow-up records (T1) were taken after 4-6 months. Dolphin Imaging software was used to measure the volumes of the nasopharynx, oropharynx, and hypopharynx. We also evaluated the craniocervical position with the use of a lateral cephalogram., Results: The variables exhibited high intraclass correlation coefficients (ICCs) when measuring the same CBCT scan twice (T0 and T0). However, The ICC between the measurements performed on the first and second CBCT scans (T0 and T1) showed that the only variable with high reproducibility between the 2 scans was cranial base, with an ICC >0.97. Average differences of 682.1 mm 3 , 2255.3 mm 3 , and 517.4 mm 3 were found for the nasopharynx, oropharynx, and hypopharynx, respectively. Regarding the cephalometric angles, average differences between T0 and T1 scans were 0.6°, 2.7°, and 0.4° for OPT.CVT, OPT.SN, and cranial base, respectively., Conclusions: Different CBCT exams with equal scanning and patient positioning protocols can result in different 3D PAS readings. A more careful interpretation of CBCT volumetric data to achieve adequate conclusions of the clinical outcomes is necessary., (Copyright © 2019 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objective: we investigated the effect of anodal transcranial direct current stimulation (tDCS) applied over the pharyngeal motor area in dysphagia associated with multiple sclerosis (MS)., Methods: Eighteen MS patients with dysphagia associated with brainstem involvement were randomized to receive either "real" or "sham" tDCS., Primary Outcome: The Penetration/Aspiration Scale (PAS)., Secondary Outcomes: changes in electromyographic (EMG) parameters and pharyngeal cortical motor evoked potentials (MEPs). Patients were evaluated at baseline (T 0 ), at the end of 5-session cycle of tDCS stimulations (T 1 ), after two (T 2 ), and four (T 3 ) weeks., Results: the PAS values were significantly lower in the active group than in "sham" group at T 1 , and at T 3 . Over the post-stimulation periods, PAS significantly improved only in the "real" group. As regards the secondary outcomes, we observed a statistically significant difference between the 2 groups only in the MEPs amplitude at T 1 . The comparison between baseline and each of the post-stimulation times showed significant differences only of the "real" group across all the secondary parameters., Conclusions: Our findings support a beneficial effect of anodal tDCS applied to the pharyngeal motor cortex in MS-associated dysphagia., Significance: Considering its safety and efficacy, tDCS may represent an important resource in MS-associated dysphagia., (Copyright © 2019. Published by Elsevier B.V.)

Introduction: The assessment of the volumetric changes of the airways after adenotonsillectomy has gained popularity among orthodontists, but the validity of such evaluation is not clear., Methods: Thirty patients with obstructive sleep apnea diagnosed with the use of polysomnography (PSG) were evaluated according to the Apnea and Hypopnea Index (AHI), the obstructive apnea index (OAI), the oxygen desaturation index (ODI), the lowest oxygen saturation (LSpO 2 ), and the average oxygen saturation (ASpO 2 ). The volume and the minimal cross-section of lower (oropharynx and velopharynx) and upper (nasopharynx) spaces of the airways were calculated. Patients were adenotonsillectomized; posttreatment data were collected after 12 months. Thirty comparison patients also had the volume of airways evaluated., Results: A statistically significant improvement (P < 0.05) of most PSG parameters was observed after adenotonsillectomy: AHI from 14.5 to 5.2, OAI from 9.4 to 5.5, ODI from 14.6 to 6.5, and LSpO 2 from 77% to 94%). A significant increase in airway volume of the lower space (from 2571.5 mm 3 to 5276.3 mm 3 ) and the upper space (from 726 mm 3 to 1056.9 mm 3 ), as well as in the minimal cross-section of the airways (from 98.5 mm 2 to 335.8 mm 2 ) was found in adenotonsillectomy patients. No significant volumetric changes of the airways were observed in the comparison patients. No significant correlation was found between PSG parameters and the dimensions of the airways before adenotonsillectomy. No significant correlation was found between changes of the PSG parameters and changes of the dimensions of the airways 12 months after the adenotonsillectomy., Conclusions: Adenotonsillectomy contributed to the increase of the airway volume and minimal cross-section, and to the improvement of the PSG parameters, but there was no correlation between the magnitude of the anatomic changes and the improvement of the breathing mode., (Copyright © 2019 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Background: Parapharyngeal space abscesses (PPSA) are deep-space neck infections that are associated with significant morbidity and, rarely, mortality if not promptly diagnosed and treated. The diagnosis is often difficult, as the clinical presentation can mimic peritonsillar abscesses (PTA). Transoral point-of-care ultrasound (POCUS) may be a useful tool to help distinguish PTAs from other deep-space infections such as PPSAs., Case Report: A woman presented to the Emergency Department (ED) with fever, sore throat, trismus, and unilateral tonsillar swelling from a walk-in clinic with a preliminary diagnosis of PTA for drainage. A POCUS performed by the emergency medicine resident in the ED demonstrated normal tonsils. However, it revealed evidence of a PPSA. A computed tomography scan was performed, which confirmed the diagnosis. The patient was admitted to the otolaryngology service for antibiotics and steroids, with subsequent improvement and discharge home. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: In this case, the use of POCUS in the ED avoided an unnecessary invasive procedure, and facilitated the correct diagnosis of an uncommon condition., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Target volume selection and delineation for both the primary tumor and the lymph nodes are critical steps in the treatment of head and neck tumors with Intensity Modulated Radiation therapy (IMRT). These steps should be based on a probabilistic approach, which is that selection and delineation will be considered as optimal when reaching the best compromise between a too tight volume that could be associated to an unacceptable rate of local recurrence, and a too large volume, which could be associated to an unacceptable rate of treatment morbidity. Failure to do so have been reported to be associated to a higher risk of loco-regional recurrences and/or morbidity after treatment. In this framework, groups of experts proposed sets of guidelines for the radiation oncology community, aiming at standardizing radiotherapy practices of head and neck cancer patients. Although in constant improvement, such guidelines have been shown to translate into more consistent treatment approaches. This review article summarizes the knowledge accumulated over the years on target volume selection and delineation and tries to reconcile the various schools of thoughts on the topic., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Although the ipsilateral inferior petrosal sinus (IPS) is preferred for treatment of cavernous sinus dural arteriovenous fistulas (CS-dAVFs), this method is problematic if ipsilateral IPS is occluded. We describe our experience in treating CS-dAVFs with ipsilateral IPS occlusion via the ascending pharyngeal artery (APA)., Methods: Between January 2013 and June 2017, of 36 CS-dAVFs, 23 with ipsilateral IPS occlusion were identified. Clinical charts, procedural data, angiographic results, and follow-up data were retrospectively reviewed., Results: Of 23 CS-dAVFs, 16 displayed a single or dominant feeding APA on cerebral angiography, of which 13 were treated via the APA initially. Fistulas were occluded successfully through the neuromeningeal trunk of the APA in 7 cases and through the superior pharyngeal branch of the APA in 3 cases. Glue leakage occurred in 2 cases via the superior pharyngeal branch of the APA, and superior pharyngeal branch rupture occurred during superselection of the microguidewire in 1 patient, who was treated by opening the occluded ipsilateral IPS. During the follow-up period, 12 of 13 patients had complete occlusion, and no cranial nerve palsy occurred., Conclusions: CS-dAVF with ipsilateral IPS occlusion can be treated via various methods. Embolization through the APA as an initial access is a reasonable choice., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Introduction: The purpose of this article was to evaluate the pharyngeal space volume, and the size and shape of the mandible and the hyoid bone, as well as their relationships, in patients with different facial types and skeletal classes. Furthermore, we estimated the volume of the pharyngeal space with a formula using only linear measurements., Methods: A total of 161 i-CAT Next Generation (Imaging Sciences International, Hatfield, Pa) cone-beam computed tomography images (80 men, 81 women; ages, 21-58 years; mean age, 27 years) were retrospectively studied. Skeletal class and facial type were determined for each patient from multiplanar reconstructions using the NemoCeph software (Nemotec, Madrid, Spain). Linear and angular measurements were performed using 3D imaging software (version 3.4.3; Carestream Health, Rochester, NY), and volumetric analysis of the pharyngeal space was carried out with ITK-SNAP (version 2.4.0; Cognitica, Philadelphia, Pa) segmentation software. For the statistics, analysis of variance and the Tukey test with a significance level of 0.05, Pearson correlation, and linear regression were used., Results: The pharyngeal space volume, when correlated with mandible and hyoid bone linear and angular measurements, showed significant correlations with skeletal class or facial type. The linear regression performed to estimate the volume of the pharyngeal space showed an R of 0.92 and an adjusted R 2 of 0.8362., Conclusions: There were significant correlations between pharyngeal space volume, and the mandible and hyoid bone measurements, suggesting that the stomatognathic system should be evaluated in an integral and nonindividualized way. Furthermore, it was possible to develop a linear regression model, resulting in a useful formula for estimating the volume of the pharyngeal space., (Copyright © 2018 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the short- and long-term impact of mandibular-only advancement on pharyngeal airway space (PAS) changes by using cone-beam computed tomography (CBCT) and a new segmentation software. Furthermore, to determine whether a correlation exists between forward movement and PAS gain., Materials and Methods: A retrospective evaluation of a homogeneous cohort of Class II patients who had undergone mandibular-only advancement was performed. Pre- (T0), post- (T1), and 1-year post-operative (T2) CBCT scans were obtained in each case, and the changes in PAS parameters (volume and smallest cross-sectional area) were compared with new segmentation software. Mandibular advancement was measured and correlated with PAS parameters., Results: A significant postoperative gain in all airway parameters compared with baseline was shown for T1 (p = 0.02), with an additional increase for T2 (p < 0.001). No significant linear association between the movement of the measurement points and any other PAS parameters could be discerned (p > 0.05)., Conclusion: Our findings indicate that bilateral mandibular-only advancement surgery results in a significant widening of the PAS in Class II patients. Long-term adaption of the PAS also occurs after surgery implying an additional gain of PAS over time. Sicat Air® software seems to be a sufficient and promising tool for PAS evaluation., (Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Introduction: In this study, we investigated volumetric and dimensional changes to the pharyngeal airway space after isolated mandibular setback surgery for patients with Class III skeletal dysplasia., Methods: Records of 28 patients who had undergone combined orthodontic and mandibular setback surgery were obtained. The sample comprised 17 men and 11 women. Their mean age was 23.88 ± 6.57 years (range, 18-52 years). Cone-beam computed tomography scans were obtained at 3 time points: before surgery, average of 6 months after surgery, and average of 1 year after surgery. Oropharyngeal, hypopharyngeal, and total volumes were calculated. The lateral surface and anteroposterior dimensions at the minimal axial areas for oropharyngeal and hypopharyngeal volumes and mean mandibular setback were determined., Results: The mean mandibular setback was 9.93 ± 5.26 mm. Repeated measures analysis of variance determined an overall significant decrease between the means for 6 months and up to 1 year after surgery for oropharyngeal and hypopharyngeal volumes, anteroposterior at oropharyngeal, lateral surface at oropharyngeal, and anteroposterior at hypopharyngeal. No strong correlation between mandibular setback surgery and pharyngeal airway volumes or dimensions was determined., Conclusions: After mandibular setback surgery, pharyngeal airway volume, and transverse and anteroposterior dimensions were decreased. Patients undergoing mandibular setback surgery should be evaluated for obstructive sleep apnea and the proposed treatment plan modified according to the risk for potential airway compromise., (Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objectives: The purpose of the study was to test the intra and interobserver reliability of manual volumetric segmentation of pharyngeal and sinonasal airway subregions., Study Design: Cone beam computed tomography data of 15 patients were collected from an orthodontic clinical database. Two experienced orthodontists independently performed manual segmentation of the airway subregions. Four performance measures were considered to test intra and interobserver reliability of manual segmentation: (1) volume correlation, (2) mean slice correlation, (3) percentage of volume difference, and (4) percentage of nonoverlapping voxels., Results: Intra and interobserver reliability was observed to be greater than 0.96 for the entire pharyngeal and sinonasal airway sinus subregions by both observers using the volume correlation method. Mean slice correlation was found to be greater than 0.84, showing the existence of nonoverlapping voxels. Therefore, the percentage of nonoverlapping voxels was used as a reliability measure and was found to be less than 20% for both intra and interobserver markings., Conclusions: The mean slice correlation and percentage of nonoverlapping voxels were the most reliable performance measures of segmentation correctness. Volume correlation and the percentage of volume difference were observed to be the most reliable performance measures for volume correctness., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Purpose: The aim of this study was to evaluate changes in the pharyngeal airway space (PAS) and hyoid bone position after orthognathic surgery with cone-beam computed tomography (CBCT)., Material and Methods: This study was conducted with the tomographic records of 30 patients with skeletal class II or III deformities submitted to two different types of orthognathic surgery: Group 1 (n = 15), maxillary advancement, and mandibular setback; and Group 2 (n = 15), maxillomandibular advancement. CBCT scans were acquired preoperatively (T 0 ); and at around 1.5 months (T 1 ) and 6.7 months (T 2 ) postoperatively. PAS volume, minimum cross-sectional area (min CSA), and hyoid bone position changes were assessed with Dolphin Imaging 3D software, and results analyzed with ANOVA and a Tukey-Kramer test (p < 0.05)., Results: The hyoid bone was significantly displaced in the horizontal dimension, moving posteriorly in Group 1, and anteriorly in Group 2. Although PAS volume and min CSA increased after both surgeries, these measurements were significantly larger only in Group 2. The significant differences that existed between groups preoperatively no longer existed after the surgeries., Conclusions: Both orthognathic surgeries assessed resulted in changes in hyoid bone position and increased PAS volume and min CSA, particularly after maxillomandibular advancement surgery., (Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Background: Several surgical approaches for the treatment of pathologies of the craniovertebral junction (CVJ) and high cervical regions have been reported. For the best postoperative results, selection of a surgical route to treat such pathologies should be based on a complete understanding of the approach., Case Description: A 64-year-old woman presented with a 5-year history of motor and sensory disturbances in her right upper extremity. Cervical magnetic resonance imaging (MRI) showed a slightly enhanced mass at the C2-C4 level. Sagittal T2-weighted MRI revealed a hyperintense dumbbell-shaped mass involving a damaged C3 vertebral body. We performed a 2-stage operation to achieve gross total removal of the tumor. In the first operation, a posterior approach was used to remove the intracanalicular tumor, achieve spinal cord decompression, and establish a histological diagnosis of the tumor (subsequently diagnosed as a chordoma). In the second operation, gross total removal of the chordoma was achieved via the anterior high cervical retropharyngeal approach. We used iliac bone and titanium plates for the bony fusion., Conclusions: Our results indicate that the high cervical retropharyngeal approach is a reasonable option for pathologies located in the anterior or anterolateral portions of high cervical regions. This approach is an alternative to the transoral approach to the ventral CVJ and high cervical regions., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objective: To describe our experience in treating esophageal and pharyngeal perforation after anterior cervical spine surgery., Methods: Six patients with esophageal injury and one patient with pharyngeal injury after anterior cervical spinal surgery, managed at our department between 2000 and 2015, were analyzed retrospectively., Results: During the study period, 7 patients (6 male and 1 female; mean age, 45 years) presented with esophageal perforation. The original anterior cervical spinal surgery was performed due to trauma in 2 patients and because of a degenerative cervical disorder in 5. Early esophageal perforation was diagnosed in 2 patients, and delayed esophageal injury due to chronic irritation with the cervical implants was noted in 5. Three of the five delayed perforation cases were related to cervical instrument displacement. Two patients showed no definite signs of infection, whereas 5 patients had various symptoms, including fever, neck pain, odynophagia, neck swelling, and upper extremity weakness. Two patients with a large defect underwent surgical repair and three with minimal perforation due to chronic irritation from the implants underwent instrument removal without direct repair of defect. Two asymptomatic patients received no intervention. Six patients with infection completely recovered from esophageal injury after treatment for a mean duration of 5.2 weeks (range, 4-8 weeks). One patient died because of postoperative pneumonia and sepsis after implant removal., Conclusions: Esophageal and pharyngeal injury after cervical spinal surgery may occur either directly due to spinal trauma and vigorous intraoperative retraction or due to chronic irritation with cervical implants. In cases of perforation associated with infection, various surgical modalities, including primary closure and reinforcement with a flap, could be considered depending on factors such as esophageal defect size, infection severity, and timing of recognition of injury., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background.: Increased tongue thickness is likely to be associated with difficult airways. However, no methods to evaluate tongue thickness were available. Currently, tongue thickness can be measured by ultrasonography. The present study investigated the predictive value of tongue thickness to predict difficult tracheal intubation., Methods.: Adult patients undergoing tracheal intubation and general anaesthesia were enrolled in the study. Tongue thickness was assessed using submental ultrasonography in the median sagittal plane before anaesthesia. Airway assessments were conducted. Ratios of tongue thickness to thyromental distance were calculated to investigate the potential predictive value of their combination. The primary outcome was difficult tracheal intubation. A multivariable logistic regression and receiver operating characteristic curve analysis were used., Results.: In total, 2254 patients were analysed. One hundred and forty-two (6.3%) patients experienced difficult laryngoscopy, and 51 (2.3%) patients experienced difficult tracheal intubation. Increased tongue thickness (>6.1 cm) was an independent predictor for difficult tracheal intubation [sensitivity 0.75, 95% confidence interval (CI) 0.60-0.86; specificity 0.72, 95% CI 0.70-0.74]. An area under the curve of 0.78 (95% CI 0.77-0.80) for predicting difficult tracheal intubation was calculated. Increased ratios of tongue thickness to thyromental distance (>0.87) presented a considerable area under the curve (0.86, 95% CI 0.84-0.87), sensitivity (0.84, 95% CI 0.71-0.93), and specificity (0.79, 95% CI 0.77-0.81)., Conclusions.: Tongue thickness measured by ultrasonography and its ratio to thyromental distance present significant capacities to predict difficult tracheal intubation., Clinical Trial Registration.: ChiCTR-RCS-14004539., (© The Author 2017. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com)

The aim of this study was to evaluate both the 2-dimensional (2D) and 3-dimensional (3D) configuration of the posterior airway space (PAS) in healthy 239 patients using cone-beam computed tomography (CBCT). In particular, we investigated the correlation between the 2D and 3D measurements in view of the potential impact on diagnosis of upper airway obstruction. The pharyngeal airway of each patient was studied at five levels: the level of the posterior nasal spine (PNS), the level of half-height of the PNS and the tip of the soft palate, the level of the tip of the soft palate, the level of the anterior-inferior point of the second vertebra, and at least the level of the top of the epiglottis. At each of these levels, the anterior-posterior dimension as well as the corresponding cross-sectional area was measured. Furthermore we measured the volume of the whole PAS between the first and the last level and compared it with the corresponding 2D values. Differences between genders and age effects were estimated in an analysis of covariance. P values <.05 were considered significant. Linear models were fitted to find the optimal formula to calculate the area or volume from measured distances. Limits of agreement were calculated as 2 ± residual standard deviations. We generated normal 2D and 3D values of the PAS for a normal population. In regard to age, no significant differences were observed. Significant differences were assessed between healthy males and females; however no correlation was observed between the obtained measurements in 2D axial view and the corresponding cross-sectional areas and mean volume in 3D view. In summary, radiologic imaging is a helpful tool to evaluate the airway space in patients with OSAS. However, drawing conclusions from 2D PAS imaging to assess 3D PAS configuration is not reliable, since there is no sufficient correlation between posterior-anterior distances and the corresponding cross-sectional areas., (Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Introduction: Maxillomandibular transverse osteodistraction (MMTOD) is an alternative approach to the traditional treatment for transverse maxillary and mandibular deficiencies and crowding. The aim was to report soft and hard-tissues changes and airway volume variation., Methods: In this study, skeletally mature, non-syndromic patients with transverse maxillary and mandibular hypoplasia, who underwent a MMTOD between 2010 and 2012, were included. Surgical changes were analysed using clinical evaluation, three-dimensional facial surface data and computed tomography analysis before (T0) and after the completion of post-op orthodontic treatment (T1)., Results: Nineteen patients (eight males and eleven females; average age: 26.3 years) were enrolled. MMTOD produces facial changes in the cheek, paranasal areas, nasal base and chin. Facial changes are mostly explained by the underlying skeletal movements, which are essentially represented by the transverse enlargement of both the maxilla and the mandible. Following MMTOD, the airway volume and the lateral dimension of the cross-sectional airway increased significantly., Conclusions: MMTOD is a technique that allows an increase in airway volume and in both maxillary and mandibular arch perimeters simultaneously by increasing skeletal width. Facial appearance is improved and a stable occlusion is obtained., (Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Purpose: To evaluate the feasibility of utilizing serial dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) prospectively for early prediction of neoadjuvant chemotherapy (NAC) response in nasopharyngeal carcinoma (NPC) patients., Materials and Methods: Sixty-three advanced NPC patients were recruited and received three DCE-MRI exams before treatment (Pre-Tx), 3days (Day3-Tx) and 20days (Day20-Tx) after initiation of chemotherapy (one NAC cycle). Early response to NAC was determined based on the third MRI scan and classified partial response (PR) as responders and stable disease (SD) as non-responders. After intensity-modulated radiotherapy (IMRT), complete response (CR) patients were classified as responders. The kinetic parameters (K trans , K ep , v e , and v p ) derived from extended Tofts' model analysis and their corresponding changes ΔMetrics (0-X) (X=3 or 20days) were compared between the responders and non-responders using the Student's T-test or Mann-Whitney U test., Results: Compared to the SD group, the PR group after one NAC cycle presented significantly higher mean K trans values at baseline (P=0.011) and larger ΔK trans (0-3) and ΔK ep(0-3) values (P=0.003 and 0.031). For the above parameters, we gained acceptable sensitivity (range: 66.8-75.0%) and specificity (range: 60.0-66.7%) to distinguish the non-responders from the responders and their corresponding diagnosis efficacy (range: 0.703-0.767). The PR group patients after one NAC cycle showed persistent inhibition of tumor perfusion by NAC as explored by DCE-MRI parameters comparing to the SD group (P<0.05) and presented a higher cure ratio after IMRT than those who did not (83.3% vs. 73.8%)., Conclusions: This primarily DCE-MRI based study showed that the early changes of the kinetic parameters during therapy were potential imaging markers to predicting response right after one NAC cycle for NPC patients., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Introduction: The aim of this study was to examine the effects of orthodontic treatment with and without extractions on the anatomic characteristics of the upper airway in adults., Methods: For this retrospective study, the pretreatment and posttreatment cone-beam computed tomography scans of 74 adult patients meeting defined eligibility criteria were analyzed. Imaging software was used to segment and measure upper airway regions including the nasopharynx, the retropalatal, and retroglossal areas of the oropharynx, as well as the total airway. The Wilcoxon signed rank test was used to compare volumetric and minimal cross-sectional area changes from pretreatment to posttreatment., Results: The reliability values were high for all measurements, with intraclass correlation coefficients of 0.82 or greater. The volumetric treatment changes for the extraction and nonextraction groups were as follows: total airway, 1039.6 ± 3674.3 mm 3 vs 1719.2 ± 4979.2 mm 3 ; nasopharynx, 136.1 ± 1379.3 mm 3 vs -36.5 ± 1139.8 mm 3 ; retropalatal, 412.7 ± 3042.5 mm 3 vs 399.3 ± 3294.6 mm 3 ; and retroglossal, 412.5 ± 1503.2 mm 3 vs 1109.3 ± 2328.6 mm 3 . The treatment changes in volume or minimal cross-sectional area for all airway regions examined were not significantly (P >0.05) different between the extraction and nonextraction groups., Conclusions: Orthodontic treatment in adults does not cause clinically significant changes to the volume or the minimally constricted area of the upper airway. These results suggest that dental extractions in conjunction with orthodontic treatment have a negligible effect on the upper airway in adults., (Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: Our objectives were to assess reliability, validity, and time efficiency of semiautomatic segmentation using Segura software of the nasal and pharyngeal airways, against manual segmentation with point-based analysis with color mapping., Methods: Pharyngeal and nasal airways from 10 cone-beam computed tomography image sets were segmented manually and semiautomatically using Segura (University of Alberta, Edmonton, Alberta, Canada). To test intraexaminer and interexaminer reliabilities, semiautomatic segmentation was repeated 3 times by 1 examiner and then by 3 examiners. In addition to volume and surface area, point-based analysis was completed to assess the reconstructed 3-dimensional models from Segura against manual segmentation. The times of both methods of segmentation were also recorded to assess time efficiency., Results: The reliability and validity of Segura were excellent (intraclass correlation coefficient, >0.9 for volume and surface area). Part analysis showed small differences between the Segura and manually segmented 3-dimensional models (greatest difference did not exceed 4.3 mm). Time of segmentation using Segura was significantly shorter than that for manual segmentation, 49 ± 11.0 vs 109 ± 9.4 minutes (P <0.001)., Conclusions: Semiautomatic segmentation of the pharyngeal and nasal airways using Segura was found to be reliable, valid, and time efficient. Part analysis with color mapping was the key to explaining differences in upper airway volume and provides meaningful and clinically relevant analysis of 3-dimensional changes., (Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)