Reliability of fluoroscopic examination of nasopharyngeal dorsoventral dimension change in pugs and French bulldogs.

OBJECTIVE: To compare intra- and interobserver agreements in two-dimensional measurements of changes in nasopharyngeal dimensions during breathing in pugs and French bulldogs. STUDY DESIGN: Experimental randomized study. ANIMALS: A total of 20 French bulldogs and 16 pugs. METHODS: Four observers with different levels of experience measured the dorsoventral dimensions of the nasopharynx during inspiration and expiration on fluoroscopy videos. Measurements were performed at the maximal narrowing of the nasopharynx for the functional method and at the level of the tip of the epiglottis for the anatomically adjusted method. The intra- and interobserver agreements of the measurements, ratio of the dynamic nasopharyngeal change (ΔL), and grade of nasopharyngeal (NP) collapse (no, partial or complete) were evaluated. RESULTS: The functional method resulted in intraobserver correlation coefficients of 0.532 (p < .01) and 0.751 (p < .01) and interobserver correlation coefficients of 0.378 (p < .01) and 0.621 (p < .01) for NP collapse grade and ΔL, respectively. The anatomically adjusted method, 0.491 (p < .01) and 0.576 (p < .01) and 0.495 (p < .01) and 0.729 (p < .01) for NP collapse grade and ΔL, respectively, were being used. One observer (radiologist) achieved intraobserver correlation coefficients >0.9 for both methods. CONCLUSION: Fair interobserver agreement was found for NP collapse grade (functional method), moderate intra- and interobserver agreements were found for NP collapse grade and ΔL (both methods) while intraobserver agreement for ΔL was good (functional method). CLINICAL SIGNIFICANCE: Both methods seem repeatable and reproducible but only for experienced radiologists. The use of ΔL may offer higher repeatability and reproducibility than grade of NP collapse regardless of the method used.

Non-brachycephalic dogs with stertor have higher nasopharyngeal collapsibility compared with dogs without stertor and foramen lacerum level is ideal for evaluating nasopharyngeal collapse on dynamic CT.

Stertor, a clinical sign associated with obstructive airway syndrome, is often observed in non-brachycephalic dogs. This prospective, case-control study aimed to compare soft palate dimensions, nasopharyngeal cross-sectional area (CSA), and nasopharyngeal collapsibility at various locations in non-brachycephalic dogs with and without stertor. A total of 50 dogs were recruited and stratified into control (n = 34) and stertor (n = 13) groups. Static and dynamic computed tomography was conducted without tracheal intubation, and the following variables were calculated: normalized soft palate length and thickness, normalized maximum and minimum nasopharyngeal CSAs (rCSAmax and rCSAmin), and nasopharyngeal collapsibility at the level of the cranial end of the soft palate, pterygoid hamulus, foramen lacerum, bony labyrinth, and caudal end of the soft palate. The stertor group demonstrated significantly lower rCSAmax and rCSAmin, as well as higher nasopharyngeal collapsibility compared with the control group, while no significant differences were noted in the soft palate dimension. Evaluating nasopharyngeal collapse at the foramen lacerum level was recommended due to the clear presence of identifiable bony landmarks and lower overlap in the nasopharyngeal collapsibility between dogs with and without stertor. Physical dimensions of the soft palate may not be the primary contributing factor to nasopharyngeal collapse and clinical signs in non-brachycephalic dogs.

Development and validation of predictive models for skeletal malocclusion classification using airway and cephalometric landmarks.

OBJECTIVE: This study aimed to develop a deep learning model to predict skeletal malocclusions with an acceptable level of accuracy using airway and cephalometric landmark values obtained from analyzing different CBCT images. BACKGROUND: In orthodontics, multitudinous studies have reported the correlation between orthodontic treatment and changes in the anatomy as well as the functioning of the airway. Typically, the values obtained from various measurements of cephalometric landmarks are used to determine skeletal class based on the interpretation an orthodontist experiences, which sometimes may not be accurate. METHODS: Samples of skeletal anatomical data were retrospectively obtained and recorded in Digital Imaging and Communications in Medicine (DICOM) file format. The DICOM files were used to reconstruct 3D models using 3DSlicer (slicer.org) by thresholding airway regions to build up 3D polygon models of airway regions for each sample. The 3D models were measured for different landmarks that included measurements across the nasopharynx, the oropharynx, and the hypopharynx. Male and female subjects were combined as one data set to develop supervised learning models. These measurements were utilized to build 7 artificial intelligence-based supervised learning models. RESULTS: The supervised learning model with the best accuracy was Random Forest, with a value of 0.74. All the other models were lower in terms of their accuracy. The recall scores for Class I, II, and III malocclusions were 0.71, 0.69, and 0.77, respectively, which represented the total number of actual positive cases predicted correctly, making the sensitivity of the model high. CONCLUSION: In this study, it is observed that the Random Forest model was the most accurate model for predicting the skeletal malocclusion based on various airway and cephalometric landmarks.

Retrospective analysis of the upper airway anatomy and Sella turcica morphology across different skeletal malocclusions: a computerized technique.

OBJECTIVE: This study aimed to investigate the normal volumetric space and variations in the measurements of different landmarks in adults with different skeletal relations of the maxilla and the mandible based on CBCT data. The study also analyses these landmarks to locate any correlations. BACKGROUND: Numerous studies in orthodontics have found a relationship between orthodontic treatment and changes in the anatomy and function of the airway. Severe changes in airway morphology can cause breathing difficulties, lower quality of life, and even result in life-threatening conditions such as obstructive sleep apnoea. Consequently, orthodontic diagnosis and treatment planning require a thorough understanding of the airway space and its function. METHODS: The present retrospective study was conducted using CBCT records of 120 adult patients, containing 40 samples of each skeletal class (20 males and 20 females). The boundaries were defined for the 3 major regions: the nasopharynx, the oropharynx, and the hypopharynx. Various measurements were recorded across these regions, as well as selective cephalometric landmarks. The obtained data was used to calculate average and standard deviation, while regression analysis was used to evaluate correlations and t-test was used to test statistical significance of gender differences. RESULTS: The results demonstrate that skeletal Class III individuals exhibit a reduced airway volume in the nasopharynx compared to other groups, whereas skeletal Class II individuals displayed a diminished airway volume in the hypopharynx. A strong correlation was observed for Sella turcica parameters. There were no significant differences in skeletal parameters across genders. Nasopharynx cavity volume demonstrated significant differences between skeletal Class I-Class III as well as between skeletal Class II-Class III. Hypopharynx cavity volume also demonstrated significant differences between skeletal Class I-Class II and between skeletal Class II-Class III. CONCLUSION: The major findings are the presence of a reduced nasopharyngeal volume in skeletal Class III malocclusions while skeletal Class II individuals displayed a diminished hypopharyngeal volume, making these critical areas to consider during the diagnostic and orthodontic treatment planning stages. This study also revealed a consistent correlation between Sella turcica parameters across various facial skeletal profiles, with skeletal Class II patients exhibiting a distinct pattern and skeletal Class I and Class III demonstrating an average relationship.

An unusual case of long-standing retained nasopharyngeal foreign body.

The nasopharynx is a rare anatomical location where a foreign body may become lodged after being ingested or inhaled. We are presenting a rare case of nasopharyngeal foreign body impaction in a two-and-a-half-year-old child that had been missed for almost a year. The child presented with a history of right-sided foul-smelling nasal discharge, snoring and mouth breathing. An X-Ray soft tissue lateral view of the post-nasal space showed an irregular partially radiopaque nasopharyngeal foreign body. The removal of the foreign body was performed under general anaesthesia successfully. Foreign body impaction in the nasopharynx can easily be missed and it is important to keep this region in mind when dealing with missing inhaled or ingested foreign bodies.

Comparative study of optical coherence tomograph and histological images of eustachian tube nasopharyngeal region and adjacent structures in vivo and ex-vivo miniature pigs.

OBJECTIVES: Optical Coherence Tomograph (OCT) imaging technology can be used to examine, in vivo, the human ET. At present, it is impossible to achieve the OCT scanning vivo and ex vivo in the same individual human body, or study the consistency between OCT images and histological images of the eustachian tube nasopharyngeal region and adjacent structures. The aim of this study was to determine the consistency between OCT images and histological sections in vivo and ex vivo in miniature pigs. METHODS: OCT imaging was performed on five adult miniature pigs in vivo and ex vivo. The images of the eustachian tube OCT (ET-OCT), nasopharynx OCT (NP-OCT) and histological cross sections were further studied. RESULTS: All five miniature pigs achieved the OCT scan successfully, acquiring ET-OCT and NP-OCT images in vivo and ex vivo on both sides. The acquired ET OCT images closely matched the histological images, revealing details of the cartilage, submucosa, glands, and mucosa. The lower segment of the ET wall mucosa had an abundance of glands and submucosal tissues, with more low-signal areas appearing in the ex vivo images. The NP-OCT images of the nasopharynx matched the details of the mucosa and submucosal tissues. The ex-vivo OCT images showed thicker mucosa and more scattered slightly lower signal areas compared to the vivo OCT images. CONCLUSIONS: ET-OCT images and NP-OCT images matched the histological structure of eustachian tube nasopharyngeal region structures in miniature pigs both in vivo and ex vivo. OCT images may be sensitive to changes in edema and ischemia status. There is a great potential for morphological assessment of inflammation, edema, injure, mucus gland status.

Three-Dimensional Evaluation of Upper Airway Changes After Bimaxillary Surgery of Skeletal Class 3 Patients.

The aim of this study was to evaluate the 3-dimensional changes in upper airway space of class 3 patients after surgery with sleep-related breathing disturbance. This is a retrospective cohort study included 25 patients who had undergone bimaxillary orthognathic surgery with maxillary advancement and mandibular setback for skeletal class 3 deformity. The changes in minimum axial area, nasopharyngeal and oropharyngeal airway volume were determined by cone-beam computed tomography images, as well as the sleep parameters by polysomnography preoperatively and postoperatively. The impacts of mandibular setback and maxillary advancement amounts on the airway structures were evaluated and compared with other parameters. The results show that pharyngeal volume measurement means were found to be significantly increased postoperatively ( P <0.05). No significant difference was observed in the mean values of minimum axial area and sleep parameters after the operation ( P> 0.05). A positive relationship was determined between the oropharyngeal volume and minimum axial area changes at a rate of 60% ( r : 0.600). No relationship was revealed between airway volume changes and polysomnographic parameters. An increase in the total airway volume and no postoperative sleep-related disturbance symptoms were observed in the patients treated by maxillary advancement and mandibular setback surgery.

How deep do you go? Clinical prediction of nasopharyngeal depth based on facial measurements.

Nasopharyngeal depth (ND) prediction is clinically relevant in performing medical procedures, and in enhancing technique accuracy and patient safety. Nonetheless, clinical predictive variables and normative data in adults remain limited. This study aimed to determine normative data on ND and its correlation to external facial measurements. A multicenter cross-sectional study obtained data from adults presenting to otolaryngology clinics at five sites in Canada, Italy, and Spain. Investigators compared endoscopically measured depth from the nasal sill (soft tissue between the nasal ala and columella) to nasopharynx along the nasal floor to the "curved distance from the alar-facial groove along the face to the tragus" and "distance from the tragus to a plane perpendicular to the philtrum." When sinus computed tomography images were available, the distance from the nasopharynx to the nasal sill was also collected. 371 patients participated in the study (41% women; 51 years old, SD 18). Average ND was 9.4 cm (SD 0.86) and 10.1 cm (SD 0.9) for women and men, respectively (p < 0.001; 95% CI 0.46-0.86). Perpendicular distance was strongly correlated to ND (r = 0.775; p < 0.001), with an average underestimation of 0.1 cm (SD 0.65; 95% CI 0.06-0.2). The equation: ND (cm) = perpendicular distance*0.773 + 2.344, generated from 271 randomly selected participants, and validated on 100 participants, resulted in a 0.03 cm prediction error (SD 0.61; 95% CI -0.08-0.16). Nasopharyngeal depth can be approximated by the distance from the tragus to a plane perpendicular to the philtrum.

Rostral nasopharyngeal CT measurements in Chihuahuas and Pomeranians are smaller than those measured in Dachshunds.

Chihuahuas and Pomeranians are often afflicted with obstructive upper respiratory tract disease. Previous computed tomographic (CT) studies have described the dimensions and abnormalities of different parts of the upper respiratory tract in brachycephalic dogs. However, Chihuahuas and Pomeranians were not included. The objective of this study was to determine the transverse-sectional (TSA) dimensions of the nasopharynx, cricoid, and trachea of Chihuahuas and Pomeranians, and investigate whether or not Chihuahuas and Pomeranians had smaller airway dimensions than another non-brachycephalic breed (Dachshund). A retrospective, descriptive, single-center cross-sectional cohort study was performed. CT studies of 88 dogs were included (42 Chihuahuas, 29 Dachshunds, and 17 Pomeranians). The TSA of the rostral, mid, and caudal aspect of the nasopharynx, the cricoid and trachea at the level of C4 were determined. For all these locations, TSA/weight, nasopharynx/cricoid, nasopharynx/trachea, and cricoid/trachea ratios were determined. The rostral nasopharynx was the smallest part of the upper airways in Chihuahuas and Pomeranians. Chihuahuas had significantly smaller rostral nasopharynx TSA/weight ratios compared to Dachshunds (P < 0.0001). The rostral nasopharynx TSA/cricoid ratio and the rostral nasoharynx/trachea ratio for Chihuahuas were significantly smaller than both that of Pomeranians (P < 0.0001 and P = 0.00027) and Dachshunds (P < 0.0001 and P = 0.00084). Pomeranians had significantly smaller cricoid TSA/weight ratios compared to Chihuahuas (P = 0.0014) and Dachshunds (P = 0.00028). This study demonstrated that the nasopharynx is narrow in Chihuahuas and Pomeranians, with the smallest dimensions located at the rostral part of the nasopharynx.

Anatomical Partition-Based Deep Learning: An Automatic Nasopharyngeal MRI Recognition Scheme.

BACKGROUND: Training deep learning (DL) models to automatically recognize diseases in nasopharyngeal MRI is a challenging task, and optimizing the performance of DL models is difficult. PURPOSE: To develop a method of training anatomical partition-based DL model which integrates knowledge of clinical anatomical regions in otorhinolaryngology to automatically recognize diseases in nasopharyngeal MRI. STUDY TYPE: Single-center retrospective study. POPULATION: A total of 2485 patients with nasopharyngeal diseases (age range 14-82 years, female, 779[31.3%]) and 600 people with normal nasopharynx (age range 18-78 years, female, 281[46.8%]) were included. SEQUENCE: 3.0 T; T2WI fast spin-echo sequence. ASSESSMENT: Full images (512 × 512) of 3085 patients constituted 100% of the dataset, 50% and 25% of which were randomly retained as two new datasets. Two new series of images (seg112 image [112 × 112] and seg224 image [224 × 224]) were automatically generated by a segmentation model. Four pretrained neural networks for nasopharyngeal diseases classification were trained under the nine datasets (full image, seg112 image, and seg224 image, each with 100% dataset, 50% dataset, and 25% dataset). STATISTICAL TESTS: The receiver operating characteristic curve was used to evaluate the performance of the models. Analysis of variance was used to compare the performance of the models built with different datasets. Statistical significance was set at P < 0.05. RESULTS: When the 100% dataset was used for training, the performances of the models trained with the seg112 images (average area under the curve [aAUC] 0.949 ± 0.052), seg224 images (aAUC 0.948 ± 0.053), and full images (aAUC 0.935 ± 0.053) were similar (P = 0.611). When the 25% dataset was used for training, the mean aAUC of the models that were trained with seg112 images (0.823 ± 0.116) and seg224 images (0.765 ± 0.155) was significantly higher than the models that were trained with full images (0.640 ± 0.154). DATA CONCLUSION: The proposed method can potentially improve the performance of the DL model for automatic recognition of diseases in nasopharyngeal MRI. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 1.

Adenoidal-Nasopharyngeal Ratio in Healthy Adults on Cone Beam Computed Tomography.

OBJECTIVE: This study aimed to quantify the adenoidal-nasopharyngeal ratio (ANR) in a cohort of healthy adults on cone beam computed tomography (CT) using the Fujioka method, which is a reproducible measure of adenoid size and nasopharyngeal patency. METHODS: Electronic health records and maxillofacial cone beam CT in 202 consecutive patients aged 16 years and older were retrospectively reviewed. Patients with a history of adenoidectomy, sinonasal disease, lymphoproliferative disorders, and cleft palate were excluded from the study. The midsagittal reconstructed cone beam CT image was used to determine the ANR. Statistical analysis was conducted using 1-way analysis of variance. RESULTS: Of the 202 subjects, 131 were female and 71 were male. The mean ± SD subject age was 45.43 ± 20.79 years (range, 16-91 years). The mean ± SD ANR in all subjects was 0.22 ± 0.13 (range, 0.03-0.75) and in each decade of adult life was as follows: younger than 21 years, 0.39 ± 0.12; 21 to 30 years, 0.29 ± 0.11; 31 to 40 years, 0.21 ± 0.09; 41 to 50 years, 0.20 ± 0.07; 51 to 60 years, 0.16 ± 0.10; 61 to 70 years, 0.13 ± 0.05; 71 to 80 years, 0.12 ± 0.05; 81 to 90 years, 0.11 ± 0.04; and 91 years or older, 0.10 ± 0. The differences in mean ANR among the age subgroups were statistically significant ( P < 0.001). CONCLUSIONS: The mean ANR gradually decreased from 0.39 in the second decade of life to 0.16 in the sixth decade of life and plateaued at approximately 0.10 thereafter.

Target insertion depth of nasopharyngeal temperature probes in children: A prospective observational study analyzing magnetic resonance images.

BACKGROUND: Core temperature monitoring is indispensable to prevent children from perioperative thermal perturbations. Although nasopharyngeal measurements are commonly used in anesthesia and considered to reflect core temperature accurately, standardized target depths for probe insertion are unknown in children. AIMS: Our primary goal was to determine a target depth of nasopharyngeal temperature probe insertion in children by measuring distances on magnetic resonance imaging (MRI). Secondary aims were to correlate these measurements with biometric variables and facial landmark-distances to derive formulas estimating target depth. METHODS: We conducted a prospective observational study in children ≤12 years undergoing cranial MRI with anesthesia. We documented patient characteristics and measured the landmark-distances nostril-mandible, nostril-tragus, and philtrum-tragus on patient's faces. On MRI, the target point for the probe tip was considered to be the site of the nasopharyngeal mucosa with the closest proximity to the internal carotid artery. After its determination in the transverse axis and triangulation to the sagittal axis, we measured the distance to the nostril. This distance, defined as target insertion depth, was correlated with the patient characteristics and used for univariate and multiple linear regression analysis. RESULTS: One hundred twenty children with a mean age of 4.5 years were included. The target insertion depth ranged from 61.8 mm in infants to 89.8 mm in 12-year-old children. Height correlated best (ρ = 0.685, 95%-CI: [0.57-0.77]). The best-fit estimation in millimeters, "40.8 + height [cm] × 0.32,″ would lead to a placement in the target position in 67% of cases. A simplified approach by categories of 50-80, 80-110, 110-130, and >130 cm height with target insertion depths of 60, 70, 80, and 85 mm, respectively, achieved similar probabilities. CONCLUSIONS: Height-based formulas could be a valuable proxy for the insertion depth of nasopharyngeal temperature probes. Further clinical trials are necessary to investigate their measurement accuracy.

A New Method for Anterior Boundary Demarcation of the Nasopharynx in Three-Dimensional Analysis.

ABSTRACT: Three-dimensional (3D) measurements of the upper airway have been extensively applied and researched, but the division of the airway is carried out in various ways, especially when demarcating the anterior boundary of the nasopharynx. The present study was to propose a new method based on the anatomical definition for the anterior boundary demarcation of the nasopharynx used in three-dimensional analysis. Twenty computed tomography scans (age 9.5 ±â€Š2.5 years, 11 males, and 9 females) of head and neck were randomly selected and transferred to Materialism's interactive medical image control system 19.0 for segmentation of the nasopharynx. Precise localization of the reference points that determining the nasopharyngeal anterior and inferior boundaries was managed by recording their coordinates in the interface of the software. The area of the anterior and the inferior boundaries, and the volume of the nasopharynx were measured and repeated with a 2-week interval for the consistency test. Both the interobserver reliability as well as the intra-observer reliability were very high (intraclass correlation coefficients, 0.985-0.997). Paired t test showed no significant difference between the first and the second examinations. This new simple method proposed for demarcation of the nasopharyngeal anterior boundary was based on the innate anatomical boundary, which was statistically reliable, technically convenient, and clinically reasonable.

Endoscopic Removal of a Nasopharyngeal Foreign Body Stuck Within the Sphenoid Bone Using the Endonasal Transseptal Approach.

ABSTRACT: Nasopharyngeal foreign bodies (FBs), which are generally caused by a strong, external force, are seldomly encountered. Removing these FBs is challenging for otorhinolaryngological surgeons because of the vital structures surrounding the nasopharynx, such as the skull base, cranial nerves, and internal carotid artery. Here, the authors report the case of a 69-year-old man referred to our hospital after accidentally cutting his face while using a grinder. Grinder fragments were deeply embedded in the face, thus becoming nasopharyngeal FBs. The authors evaluated three-dimensional volume rendering images and immediately removed these FBs using an endoscopic endonasal transseptal approach under general anesthesia. The postoperative course was uneventful. Using the endoscopic endonasal transseptal approach after evaluating preoperative three-dimensional volume rendering images may help eliminate nasopharyngeal FBs safely.

Long-term Morphological Changes of the Velum and the Nasopharynx in Patients With Cleft Palate.

OBJECTIVE: To investigate long-term morphological changes in the soft palate length and nasopharynx in patients with cleft palate. We hypothesized that there would be differences in the morphological development of the soft palate and nasopharynx between patients with and without cleft palate and that these developmental changes would negatively affect the soft palate length to pharyngeal depth ratio involved in velopharyngeal closure for patients with cleft palate. DESIGN: Retrospective, case-control study. SETTING: Institutional practice. PATIENTS: Ninety-two patients (Group F) with unilateral cleft lip, alveolus, and palate and 67 patients (Group CLA) with unilateral cleft lip and alveolus not requiring palatoplasty were included. MAIN OUTCOME MEASURES: The soft palate length, nasopharyngeal size, and soft palate length to pharyngeal depth ratio were measured via lateral cephalograms obtained at three different periods. RESULTS: Group F showed a shorter soft palate length and smaller nasopharyngeal size than Group CLA at all periods. Both these parameters increased with age, but the increase in amount was significantly less in Group F compared with that in Group CLA. The soft palate length to pharyngeal depth ratio in Group F decreased with age. CONCLUSIONS: In patients with cleft palate, the soft palate length to pharyngeal depth ratio, which is involved in velopharyngeal closure, can change with age. Less soft palate length growth and unfavorable relationship between the soft palate and nasopharynx may be masked in early childhood but can manifest later on with age.

Radiological Evaluation of the Recesses on the Posterior Wall of the Nasopharynx with Cone-beam Computed Tomography.

BACKGROUND: The posterior wall of the nasopharynx is composed of loose connective tissue that includes many important anatomical structures. Various structures, such as the opening of the Eustachian tube (ET), the Rosenmüller fossa (RF), and the pharyngeal bursa (PB) are found here. AIM: To evaluate the nasopharynx posterior wall anatomic structures, including the Eustachian tube, Rosenmüller fossa, and pharyngeal bursa with cone-beam computed tomography. MATERIALS AND METHODS: The depth, width, and length of the Eustachian tube, Rosenmüller fossa, and pharyngeal bursa were measured in 150 patients using axial-sagittal cone-beam computed tomography. The Eustachian tube and Rosenmüller fossa distance to the midsagittal plane, the coronal region passing through the posterior end of the nasal septum, the superior-inferior extremity of the recesses, and the nasal floor plane distance were measured. The relationship between Rosenmüller fossa types and other parameters were evaluated. RESULTS: The incidence of right Rosenmüller fossa types 1, 2, and 3 were 16%, 18%, and 66%, respectively, and that of the left Rosenmüller fossa types 1, 2, and 3 were 16%, 19.3%, and 64.7%, respectively. The mean pharyngeal bursa width, length, and depth were 10.8, 5.7, and 4.0 mm, respectively; those of the Eustachian tube were 5.6, 7.1, and 7.3 m, respectively; those of the right Rosenmüller fossa were 4.0, 12.4, and 10.5 mm, respectively; and those of the left Rosenmüller fossa were 3.8, 12.5, and 10.9 mm, respectively. CONCLUSIONS: The posterior wall of the nasopharynx contains several important anatomical structures. Evaluation of these using cone-beam computed tomography has many clinical and radiological advantages. To understand and interpret the coincidental findings in CBCT, dental radiologists should have access to more detailed information concerning the anatomy of the nasopharynx.

Bacteria and viruses in the upper respiratory tract of Congolese children with radiologically confirmed pneumonia.

BACKGROUND: Acute pneumonia remains a leading cause of death among children below 5 years of age in the Democratic Republic of the Congo (DR Congo), despite introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) in 2013. Potential pathogens in the nasopharynx of hospitalised children with pneumonia have not been studied previously in DR Congo. Here we compare clinical characteristics, risk factors and nasopharyngeal occurrence of bacteria and viruses between children with severe and non-severe pneumonia. METHODS: Between June 2015 and June 2017, 116 children aged from 2 to 59 months hospitalised due to radiologically confirmed pneumonia at Panzi referral university hospital, Bukavu, Eastern DR Congo were included in the study and sampled from nasopharynx. A multiplex real-time PCR assay for detection of 15 different viruses and 5 bacterial species was performed and another multiplex PCR assay was used for pneumococcal serotype/serogroup determination. RESULTS: During the study period 85 (73%) of the children with radiologically confirmed pneumonia met the WHO classification criteria of severe pneumonia and 31 (27%) had non-severe pneumonia. The fatality rate was 9.5%. Almost all (87%) children were treated with antibiotics before they were hospitalised, in most cases with amoxicillin (58%) or trimethoprim-sulfamethoxazole (20%). The frequency of potential pathogens in the nasopharynx of the children was high, and any viral or bacterial nucleic acids present at high levels, irrespective of species or type, were significantly associated with severe pneumonia as compared with non-severe cases (52% versus 29%, p = 0.032). White blood cell count > 20,000/µL and C-Reactive Protein > 75 mg/dL were associated with severe pneumonia at admission. Fatal outcome was in the multivariable analysis associated with having a congenital disease as an underlying condition. One or more pneumococcal serotypes/serogroups could be identified in 61 patients, and out of all identified serotypes 31/83 (37%) were non-PCV13 serotypes. CONCLUSIONS: The occurrence of any bacteria or any viruses at high levels was associated with severe pneumonia at admission. Children with congenital disorders might need a higher attention when having symptoms of acute respiratory infection, as developed pneumonia could lead to fatal outcome.

Investigation of the feasibility of synthetic MRI in the differential diagnosis of non-keratinising nasopharyngeal carcinoma and benign hyperplasia using different contoured methods for delineation of the region of interest.

AIM: To assess the feasibility and preliminary diagnostic performances of relaxation times derived from synthetic magnetic resonance imaging (syMRI) for differentiating nasopharyngeal carcinoma from nasopharyngeal benign lymphoid hyperplasia, and to assess the influence of tissue segmentation method on relaxation estimates. MATERIALS AND METHODS: Fifty participants with nasopharyngeal carcinoma (NPC) and 40 participants with benign hyperplasia (NPH) who underwent syMRI examination were enrolled prospectively. T1, T2, and proton density (PD) values were obtained from four different regions of interest (ROIs), namely, partial-section, single-section, three-sections, and whole-lesion. The metrics between NPC and NPH or among different ROIs were compared using Student's t-test or one-way ANOVA. The area under curve (AUC) was calculated to assess the performance of metrics obtained from different ROIs to differentiate NPC and NPH. RESULTS: The T1, T2, and PD values for NPH were significantly higher than those for NPC, regardless of the type of ROI used, except for the PD value obtained from the whole-lesion ROI. The T2 values obtained from the single-section ROI showed the highest diagnostic accuracy in distinguishing NPC from NPH, with an AUC of 0.894, sensitivity of 0.900, and specificity of 0.800. Additionally, the T1, T2, and PD values for nasopharyngeal lesions showed no statistical difference among different kinds of ROI, except for the difference in T1 value between partial-section and other methods. CONCLUSION: Quantitative analysis of syMRI has the potential to distinguish NPC from NPH. Moreover, different types of ROI showed limited influence on the relaxation time estimation for nasopharyngeal lesions.

Aerodynamic characteristics in upper airways among orthodontic patients and its association with adenoid nasopharyngeal ratios in lateral cephalograms.

BACKGROUND: Adenoid hypertrophy among orthodontic patients may be detected in lateral cephalograms. The study investigates the aerodynamic characteristics within the upper airway (UA) by means of computational fluid dynamics (CFD) simulation. Furthermore, airflow features are compared between subgroups according to the adenoidal nasopharyngeal (AN) ratios. METHODS: This retrospective study included thirty-five patients aged 9-15 years having both lateral cephalogram and cone beam computed tomography (CBCT) imaging that covered the UA region. The cases were divided into two subgroups according to the AN ratios measured on the lateral cephalograms: Group 1 with an AN ratio < 0.6 and Group 2 with an AN ratio ≥ 0.6. Based on the CBCT images, segmented UA models were created and the aerodynamic characteristics at inspiration and expiration were simulated by the CFD method for the two groups. The studied aerodynamic parameters were pressure drop (ΔP), maximum midsagittal velocity (Vms), maximum wall shear stress (Pws), and minimum wall static pressure (Pw). RESULTS: The maximum Vms exhibits nearly 30% increases in Group 2 at both inspiration (p = 0.013) and expiration (p = 0.045) compared to Group 1. For the other aerodynamic parameters such as ΔP, the maximum Pws, and minimum Pw, no significant difference is found between the two groups. CONCLUSIONS: The maximum Vms seems to be the most sensitive aerodynamic parameter for the groups of cases. An AN ratio of more than 0.6 measured on a lateral cephalogram may associate with a noticeably increased maximum Vms, which could assist clinicians in estimating the airflow features in the UA.

Pediatric unilateral isolated choanal atresia is not associated with mandibular condyle hypoplasia.

PURPOSE: We hypothesized that the ontogeny of unilateral isolated choanal atresia involves a field defect manifesting as ipsilateral mandibular condylar hypoplasia. The topic is important because the mechanism of the unilateral isolated choanal atresia is unknown. MATERIALS AND METHODS: Retrospective self-controlled case series. We included 20 patients (2 males and 18 females, ages 2 weeks to 13 years) with unilateral isolated non-syndromic choanal atresia. We studied their high-resolution computed tomographic scans. Two otolaryngologists measured the largest cross-sectional area of the mandibular condyle in the axial plane perpendicular to the posterior border of each mandibular ramus independently. Statistical significance and inter-rater agreement were calculated with paired Wilcoxon rank sum test and Spearman's non-parametric correlation coefficient respectively. RESULTS: Cross-sectional areas of the condyles ipsilateral to the choanal atresia were not statistically different than those of the contralateral condyle (P = 0.27). Inter-observer agreement of condyle areas was excellent: Spearman's r = 0.85 on the right and r = 0.94 on the left. CONCLUSIONS: In this cohort of children with the rarity of isolated non-syndromic unilateral congenital choanal atresia, no associated mandibular condyle hypoplasia was found. The data suggest that the underlying ontogeny was unlikely attributable to a field defect.