CT and MR anatomy of the larynx and hypopharynx.

Imaging of the larynx and hypopharynx is frequently requested to assess the extent of neoplasms beyond the field of view of endoscopic evaluation. The combination of optical and cross-sectional imaging allows tumors to be classified according to AJCC/UICC guidelines. A thorough understanding of laryngeal and hypopharyngeal anatomy is crucial to guide the radiological eye along the possible pathways of the spread of diseases and to guide differential diagnoses. Computed tomography (CT) has been the first cross-sectional imaging technique used to evaluate the larynx and hypopharynx; its spatial resolution combined with volumetric capability and the use of injectable contrast medium made CT the working horse in the assessment of neoplastic and inflammatory diseases. In the last two decades, magnetic resonance (MR) supported CT in the most challenging cases, when the optimal contrast resolution due to the multisequence portfolio is needed to assess the neoplastic involvement of laryngeal cartilages, paraglottic space(s), and extra laryngeal spread. The aim of this paper is to give a comprehensive radiological overview of larynx and hypopharynx complex anatomy, combining in vivo images, anatomical sections, and images of ex vivo specimens.

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.

A case of hypopharyngeal amyloidosis by digestive endoscopy. / æ¶ˆåŒ–å† é•œæ£€æŸ¥å‘çŽ°ä¸‹å’½éƒ¨æ·€ç²‰æ ·å˜æ€§1例.

Amyloidosis is a rare disease. This paper reports a case of localized secondary hypopharyngeal amyloidosis presenting with pulmonary tuberculosis as the initial symptom. The patient lacked specific clinical manifestations and primarily exhibited symptoms such as cough, sputum production, acid reflux, belching, and abdominal pain. Chest CT indicated bronchiectasis with infection and pulmonary tuberculosis. Digestive endoscopy revealed a white mucosal elevation at the right pyriform sinus of the hypopharynx. Pathological diagnosis confirmed amyloid deposits in the hypopharyngeal mucosal tissue. The patient tested positive for anti-amyloid A antibodies, Congo red staining (+), and periodate Schiff staining (+). Amyloidosis commonly affects the digestive system and may have various etiologies, often presenting with symptoms that overlap with other digestive system diseases, leading to frequent misdiagnosis and missed optimal treatment opportunities. The hypopharynx, a highly folded and narrow chamber that serves as a common passage for the digestive and respiratory tracts, can be effectively evaluated for amyloidosis using digestive endoscopy.

Uncommon cause of respiratory failure due to a bezoar in the hypopharynx: a case report.

BACKGROUND: Trichotillomania and trichophagia cause trichobezoars, which are masses made of hair. The main presentation of this condition is abdominal pain. However, other complications include gastric outlet obstruction, nausea, vomiting, weight loss, malnutrition, hematemesis, diarrhea, and constipation. CASE PRESENTATION: A 57-year-old woman with trichotillomania was admitted to the Emergency Department with the chief complaints of dyspnea on exertion, shortness of breath, dysphagia, generalized weakness, and hoarseness. Spiral chest computed tomography (CT) scan did not reveal any parenchymal lesions Pulmonary CT angiography did not reveal pulmonary embolism. The patient was admitted to the Surgery Department for hand fasciotomy due to contrast leakage, and during laryngoscopy, a trichobezoar was detected that was removed with Magill forceps. CONCLUSIONS: Rare cases of trichobezoars can be observed in humans with gastrointestinal and respiratory symptoms. Precise and timely diagnosis are key for the prevention of more invasive diagnostic procedures.

Machine learning-based FDG PET-CT radiomics for outcome prediction in larynx and hypopharynx squamous cell carcinoma.

AIM: To determine whether machine learning-based radiomic feature analysis of baseline integrated 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET) computed tomography (CT) predicts disease progression in patients with locally advanced larynx and hypopharynx squamous cell carcinoma (SCC) receiving (chemo)radiotherapy. MATERIALS AND METHODS: Patients with larynx and hypopharynx SCC treated with definitive (chemo)radiotherapy at a specialist cancer centre undergoing pre-treatment PET-CT between 2008 and 2017 were included. Tumour segmentation and radiomic analysis was performed using LIFEx software (University of Paris-Saclay, France). Data were assigned into training (80%) and validation (20%) cohorts adhering to TRIPOD guidelines. A random forest classifier was created for four predictive models using features determined by recursive feature elimination: (A) PET, (B) CT, (C) clinical, and (D) combined PET-CT parameters. Model performance was assessed using area under the curve (AUC) receiver operating characteristic (ROC) analysis. RESULTS: Seventy-two patients (40 hypopharynx 32 larynx tumours) were included, mean age 61 (range 41-77) years, 50 (69%) were men. Forty-five (62.5%) had chemoradiotherapy, 27 (37.5%) had radiotherapy alone. Median follow-up 26 months (range 12-105 months). Twenty-seven (37.5%) patients progressed within 12 months. ROC AUC for models A, B, C, and D were 0.91, 0.94, 0.88, and 0.93 in training and 0.82, 0.72, 0.70, and 0.94 in validation cohorts. Parameters in model D were metabolic tumour volume (MTV), maximum CT value, minimum standardized uptake value (SUVmin), grey-level zone length matrix (GLZLM) small-zone low grey-level emphasis (SZLGE) and histogram kurtosis. CONCLUSION: FDG PET-CT derived radiomic features are potential predictors of early disease progression in patients with locally advanced larynx and hypopharynx SCC.

Three-Dimensional Measurement of Oropharynx and Laryngopharynx in Children With Hemifacial Microsomia.

OBJECTIVE: This study focused on evaluating different parts of the airway in patients with hemifacial microsomia classified by the Pruzansky-Kaban classification system. METHODS: Volumetric and morphologic airway parameters of 66 children with hemifacial microsomia were measured on 3D models. Using the Pruzansky-Kaban system, the patient cohort was composed of seven I-type, 14 IIa type, 27 IIb type, and 18 III type patients. RESULTS: The total airway volume was not statistically different among groups. In the 3D oropharynx models, volume and surface area of the oropharynx decreased from the type I group to the type IIb group. However, no statistically significant difference was found for length (P = 0.965) or minimum cross-sectional area (mini-CSA, P = 0.550) of the oropharynx in the type III group compared to the other groups. In the 3D laryngopharynx models, the mean-CSA (P = 0.413) and mini-CSA (P = 0.378) were not statistically different among groups. In contrast, volume (P = 0.014), length (P = 0.005), and surface area (P = 0.032) of the laryngopharynx were reduced from type I to type III. Kruskal-Wallis analysis indicated statistically significant differences of volume (P = 0.004), length (P = 0.017), and surface area (P = 0.010) of the laryngopharynx among groups I, IIa, and IIb. The mean-CSA (P = 0.247) and mini-CSA (P = 0.206) of the laryngopharynx were not correlated with the different clinical types. CONCLUSION: The mean-CSA varied significantly from type I to IIb at the level of oropharynx. In addition, the volume of the laryngopharynx decreased from type I to type III. However, type III was unique in this study with nonseverely airway measurement results.

Trajectory optimized NUFFT: Faster non-Cartesian MRI reconstruction through prior knowledge and parallel architectures.

PURPOSE: The non-uniform fast Fourier transform (NUFFT) involves interpolation of non-uniformly sampled Fourier data onto a Cartesian grid, an interpolation that is slowed by complex, non-local data access patterns. A faster NUFFT would increase the clinical relevance of the plethora of advanced non-Cartesian acquisition methods. METHODS: Here we customize the NUFFT procedure for a radial trajectory and GPU architecture to eliminate the bottlenecks encountered when allowing for arbitrary trajectories and hardware. We call the result TRON, for TRajectory Optimized NUFFT. We benchmark the speed and accuracy TRON on a Shepp-Logan phantom and on whole-body continuous golden-angle radial MRI. RESULTS: TRON was 6-30× faster than the closest competitor, depending on test data set, and was the most accurate code tested. CONCLUSIONS: Specialization of the NUFFT algorithm for a particular trajectory yielded significant speed gains. TRON can be easily extended to other trajectories, such as spiral and PROPELLER. TRON can be downloaded at http://github.com/davidssmith/TRON.

Three-Dimensional Morphological Changes of the Upper Airway in Patients With Skeletal Class III Malocclusion After Orthognathic Surgery.

OBJECTIVE: To evaluate the morphological changes of the upper airway of patients with skeletal Class III malocclusion after undergoing bilateral mandibular ramus dislocated mandibular retrogression (SSRO) or SSRO combined with Le Fort I maxillary osteotomy and 3-dimensional imaging. METHODS: All previous studies related to the upper airway in patients with skeletal class III malocclusion and orthognathic surgery were collected from the PubMed, EMB, Cochrane Library, Web of science, ClinicalKey, EBSCO, Weipu, Wanfang, China National Knowledge Infrastructure, and Chinese BioMedical Literature databases. The search date ends in August 2017. RevMan5.3 software was used to perform a meta-analysis related to upper airway morphology. Ten studies were included. RESULTS: The meta-analysis showed that 6 months after SSRO, CV1, and CV2 did not change significantly (P >0.05), whereas CV3 and CV4 narrowed (P <0.05) and remained narrow after 1 year (P <0.05). (CV1,CV2,CV3,CV4: Plans parallel to the FH plane passing through the most anterior inferior point of the anterior arch of the atlas, the 2nd cervical vertebra, the 3rd cervical vertebra, the 4th cervical vertebra.) There was no significant change in nasopharyngeal volume or laryngeal pharyngeal volume (P >0.05), but oropharyngeal volume and total volume decreased (P ≤0.01). Six months after SSRO combined with Le Fort I maxillary osteotomy, the minimum cross-sectional area of the upper airway was smaller (P <0.05), there was no significant change in nasopharyngeal volume or oropharyngeal volume (P >0.05), and oropharynx volume and total volume decreased (P <0.05). CONCLUSIONS: Single and double jaw surgery has no significant effect on nasopharynx and oropharynx, but reduces laryngopharynx and total volume; however, whether this will result in postoperative obstructive sleep apnea-hypopnea syndrome or become ameliorated over time requires more in-depth study and a longer period of clinical observation.

Cone-beam computed tomography airway measurements: Can we trust them?

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 mm3, 2255.3 mm3, and 517.4 mm3 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.

Hypopharyngeal evaluation in obstructive sleep apnea with awake flexible laryngoscopy: Validation and updates to Cormack-Lehane and Modified Cormack-Lehane scoring systems.

OBJECTIVE: To validate the use of Cormack-Lehane and Modified Cormack-Lehane scoring systems to classify patterns of hypopharyngeal airway visualization seen during awake flexible laryngoscopy among patients with obstructive sleep apnoea. STUDY DESIGN: Validation study using samples collected from a prospective database. SETTING: University Medical Center. PARTICIPANTS: Data were obtained from a retrospective review of a prospective database of flexible fiberoptic examination recordings in 274 consecutive OSA subjects (Stanford Sleep Medicine/Surgery Clinic). MAIN OUTCOME MEASURES: Single still images from awake fiberoptic laryngoscopy examinations of the vocal cords from 90 different patients were presented to 2 experts and 4 novice raters. Raters used two grading systems (Cormack-Lehane scale and Modified Cormack-Lehane) to rate vocal cord visualization. Percent agreement and Cohen's kappa statistical analysis were used to evaluate inter-rater reliability and intrarater reliability for each grading system. Feedback from the participants was then used to propose updates to further improve upon the existing grading scales for their applicability to awake flexible endoscopy. RESULTS: The Cormack-Lehane and Modified Cormack-Lehane scale both communicate unobstructed and restricted views of the vocal cords reliably. Compared to the 4-grade scale, however, a modified 5-grade Vocal Cord Grading System allows for better objective communication of common variations in hypopharyngeal airway visualization. CONCLUSION: We propose a 5-Grade Vocal Cord Grading System that builds upon existing grading systems to allow for efficient and reliable communication of hypopharyngeal airway examination during awake fiberoptic laryngoscopy.

Effects of Le Fort I Osteotomy on the Nasopharyngeal Airway-6-Month Follow-Up.

PURPOSE: The literature discussing the impact of a single Le Fort I osteotomy on nasopharyngeal airways is limited. This study assessed the volumetric changes in the nasopharyngeal airway after a single Le Fort I osteotomy and explored the correlation between these changes and 3-dimensional surgical movements of the upper jaw. MATERIALS AND METHODS: This retrospective study was conducted in 40 patients who had undergone a single Le Fort I (maxillary advancement with or without impaction) to correct Class III malocclusion with maxillary hypoplasia. Preoperative (T1) and 6-month postoperative (T2) cone-beam computed tomographic (CBCT) scans of these patients were used for analysis. Maxillary surgical movements and volumetric changes in the nasopharyngeal airway were measured. The reproducibility of the measurements was evaluated using paired t tests and intraclass correlation coefficients. The Wilcoxon test and Pearson correlation coefficient were applied to evaluate the volumetric changes in the nasopharyngeal airway space and assess the correlations of these changes to the maxillary surgical movements. RESULTS: Six patients were excluded from the study owing to major differences (>5°) in their head and neck posture between the T1 and T2 CBCT scans. The errors of the repeated measurements were insignificant (P > .05), with a high level of agreement (r = 0.99; P < .05) between the repeated digitization of the landmarks. There was a statistically significant impact of a Le Fort I osteotomy on the right maxillary sinus (decreased by 17.8%) and the lower retropalatal space (expanded by 17.3%; P < .05). The correlation between the change in airway volume and the magnitude of surgical maxillary movements was moderate (r = .4). Similarly, there was a moderate correlation between changes in the upper nasopharynx and those in the hypopharynx. CONCLUSION: The single Le Fort I osteotomy was found to increase the retroglossal airway volume. This could be important for the treatment of obstructive sleep apnea in patients with maxillary deficiency. A long-term follow-up assessment of a larger sample with a functional assessment of airway would be beneficial to confirm these findings.

Correlation of Airway Volume With Orthognathic Surgical Movement Using Cone-Beam Computed Tomography.

PURPOSE: Orthognathic surgery can induce changes in airway volume. The aim of this study was to determine whether there is a correlation of surgical movement of the maxilla or mandible to airway volume changes. MATERIALS AND METHODS: This was a prospective cohort study and the sample was composed of patients undergoing single-jaw orthognathic procedures from 2004 through 2007. Cone-beam computed tomograms were obtained before surgery (T0), immediately after surgery (T1), and at least 6 months after surgery (T2). The airway was segmented from 3-dimensional images and identified as the whole airway, consisting of the naso-, oro-, and hypopharynx. The volumetric percentage of change of the airway between time points was compared and correlated to the surgical movements using paired t test and cubic regression analysis. The level of statistical significance was set at a P value less than or equal to .05. RESULTS: The sample was composed of 33 patients. Sixteen patients underwent maxillary advancement with mean advancement of 5.4 mm (3 to 8 mm), 13 underwent mandibular advancement with mean advancement of 8.0 mm (5 to 15 mm), and 4 underwent mandibular setback of 4.0 mm. For maxillary advancement at T1, volume percentages of change for the whole airway and the naso-, oro-, and hypopharynx were 18.4 (P ≤ .05), 53.8 (P ≤ .05), 26.3, and 5.5%, respectively, and at T2, the changes were 10.0, 46.7 (P ≤ .05), 6.8, and 1.0%, respectively. For mandibular advancement at T1, volume percentages of change were 34.6 (P ≤ .05), 26.1, 54.1 (P ≤ .05), and 17.4%, respectively, and at T2, the changes were 15.0 (P ≤ .05), -3.7, 23.5 (P ≤ .05), and 12.1%, respectively. There were no meaningful long-term airway changes with mandibular setback. CONCLUSION: The study results suggest that there might be an anatomic limit to pharyngeal airway expansion associated with single-jaw orthognathic surgery.

Gender-related difference in the upper airway dimensions and hyoid bone position in Chinese Han children and adolescents aged 6-18 years using cone beam computed tomography.

OBJECTIVE: To investigate the gender-related differences in upper airway dimensions and hyoid bone position in Chinese Han children and adolescents (6-18 years) using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: CBCT-scans of 119 boys and 135 girls were selected and divided into four groups (group 1: 6-9 years; group 2: 10-12 years; group 3: 13-15 years; group 4: 16-18 years). The airway dimensions including the cross-sectional area (CSA), anteroposterior (AP) and lateral (LAT) width, length (L), mean CSA and volume (VOL) of upper airway segmentations and hyoid bone position including 11 linear and three angular measurements were investigated using Materialism's interactive medical image control system (MIMICS) 16.01 software. Gender-related differences were analyzed by two independent sample t-tests. RESULTS: No gender-related difference was found in values of the facial morphology, airway dimensions and hyoid bone position for group 1 (p > 0.05). The children and adolescents in groups 2, 3 and 4 showed significant gender-related differences in the measurement results of facial morphology, airway dimensions and hyoid bone positions (p < 0.05). What's more, the measurement values of boys were obviously larger than those of girls except some measurements in group 2. CONCLUSIONS: The measurements of airway dimensions and hyoid bone positions have gender-related differences in children and adolescents aged 10-18 years. These results could be taken into consideration during orthodontic diagnosis and treatment.

Accidental cell phone ingestion with pharyngeal impaction.

BACKGROUND: 35 year old intoxicated male ingested an unusual, large foreign object (cell phone). OBJECTIVE: To report the ingestion of an unusual large foreign object with hypopharyngeal impaction, complications, and treatment. DISCUSSION: Foreign body ingestion in the adult population is more prevalent in those who engage in drug or alcohol abuse. Impaction and perforation of the upper aerodigestive tract can lead to significant and potentially fatal complications including parapharyngeal/retropharyngeal abscess, mediastinitis, and aortoesophageal fistula. The treatment of foreign object ingestion is dependent on the type of foreign object ingested, its location, and potential for perforation. Endoscopic removal under general anesthesia is the treatment method recommended for foreign bodies impacted at the cricopharyngeus or esophagus. CONCLUSIONS: We report the only case of the accidental ingestion of an entire cell phone with casing. A plain film x-ray of the neck can be used in the assessment of the location of radiopaque foreign objects and in diagnosing potential complication.