Humans ; Respiratory System ; anatomy & histology ; Sleep Apnea, Obstructive ; etiology ; therapy

OBJECTIVE: To develop an algorithm to measure the dimensions of an airway oriented obliquely on a volumetric CT, as well as assess the effect of the imaging parameters on the correct measurement of the airway dimension. MATERIALS AND METHODS: An airway phantom with 11 poly-acryl tubes of various lumen diameters and wall thicknesses was scanned using a 16-MDCT (multidetector CT) at various tilt angles (0, 30, 45, and 60degree). The CT images were reconstructed at various reconstruction kernels and thicknesses. The axis of each airway was determined using the 3D thinning algorithm, with images perpendicular to the axis being reconstructed. The luminal radius and wall thickness was measured by the full-width-half-maximum method. The influence of the CT parameters (the size of the airways, obliquity on the radius and wall thickness) was assessed by comparing the actual dimension of each tube with the estimated values. RESULTS: The 3D thinning algorithm correctly determined the axis of the oblique airway in all tubes (mean error: 0.91 +/- 0.82degree). A sharper reconstruction kernel, thicker image thickness and larger tilt angle of the airway axis resulted in a significant decrease of the measured wall thickness and an increase of the measured luminal radius. Use of a standard kernel and a 0.75-mm slice thickness resulted in the most accurate measurement of airway dimension, which was independent of obliquity. CONCLUSION: The airway obliquity and imaging parameters have a strong influence on the accuracy of the airway wall measurement. For the accurate measurement of airway thickness, the CT images should be reconstructed with a standard kernel and a 0.75 mm slice thickness.
Algorithms ; Cone-Beam Computed Tomography/*methods ; Imaging, Three-Dimensional ; Phantoms, Imaging ; Respiratory System/*anatomy & histology

OBJECTIVE: To assess the influence of variable factors such as the size of the airway and the CT imaging parameters such as the reconstruction kernel, field-of-view (FOV), and slice thickness on the automatic measurement of airway dimension. MATERIALS AND METHODS: An airway phantom was fabricated that contained eleven poly-acryl tubes of various lumen diameters and wall thicknesses. The measured density of the poly-acryl wall was 150 HU, and the measured density of the airspace filled with polyurethane foam was -900 HU. CT images were obtained using a 16-MDCT (multidetector CT) scanner and were reconstructed with various reconstruction kernels, thicknesses and FOV. The luminal radius and wall thickness were measured using in-house software based on the full-width-half-maximum method. The measured values as determined by CT and the actual dimensions of the tubes were compared. RESULTS: Measurements were most accurate on images reconstructed with use of a standard kernel (mean error: -0.03 +/- 0.21 mm for wall thickness and -0.12 +/- 0.11 mm for the luminal radius). There was no significant difference in accuracy among images with the use of variable slice thicknesses or a variable FOV. Below a 1-mm threshold, the measurement failed to represent the change of the real dimensions. CONCLUSION: Measurement accuracy was strongly influenced by the specific reconstruction kernel utilized. For accurate measurement, standardization of the imaging protocol and selection of the appropriate anatomic level are essential.
Cone-Beam Computed Tomography/*methods ; Feasibility Studies ; Phantoms, Imaging ; Respiratory System/*anatomy & histology

Humans ; Respiratory System ; anatomy & histology ; physiopathology ; Sleep Apnea Syndromes ; pathology ; physiopathology ; surgery

OBJECTIVE: To inquiry the variety difference of upper airway caliber OSAHS sufferer and normal person in quiet respiration. METHOD: Twenty OSAHS sufferer who were viewed by PSG and 16 normal adults who hagve no chief complaint of sleeping disease were selected. The curves of the subjects in a respiratory cycle were recorded by respiratory monitoring system in PSG, while the morphological changes in the pharynx of all subjects were observed by fiberscope in a calm respiratory cycle, and then both of the two processes simultaneously were recorded on the same computer. According to the different stages of respiratory cycle by analyzing respiratory curve the video had been edited into pictures about the various anatomical areas in the upper airway, the cross section area and the dimension of palate and lingua and root of the tongue region upper airway whereas studied by the image tools in computer, and the changes of areas and dimensions at palate, and lingua and root of the tongue region upper airway were calculated. RESULT: It was found that there wasps a morphological change of the upper airway with the respiratory movement in the both groups. The upper airway caliber decrease with inspiration begin and reach the most narrowing at the end of inspiration, then upper airway caliber enlarges with the expiration begin and reach the most widening at the end of expiration. No matter the normal group or the OSAHS group has the obvious changes in the palate and lingua region on the diameter, the cross section area and the dimension in respiration. The changes in the palate and lingua region on the diameter, the cross section area and the dimension of OSAHS group were greater than normal group. No matter OSAHS group or normal group on the diameter and cross section area change in the palate was obviously more than the tongue area and the root of tongue area. The changes of OSAHS group on the dimension in the palate were greater than the tongue area and the root of tongue area. CONCLUSION There are periodically changes of upper airway during respiration cycle in normal adults and OSAHS patients. The effects of respiration on upper airway caliber of OSAHS patients are more obviously than normal adults, and the increasing effects in OSAHS patients is one of OSAHS etiology.
Adult ; Case-Control Studies ; Humans ; Male ; Middle Aged ; Palate ; anatomy & histology ; pathology ; Palate, Soft ; anatomy & histology ; pathology ; Pharynx ; anatomy & histology ; pathology ; Respiration ; Respiratory System ; Sleep Apnea, Obstructive ; pathology ; physiopathology ; Tongue ; anatomy & histology ; pathology

OBJECTIVEThe purpose of this study was to investigate the effects of Fränkel II appliance on the upper airway of children.

METHODSThe subjects consisted of 20 patients with Angle Class II, division I malocclusion (10 males and 10 females). The ages of all cases were ranged in 9-10 years. Each experimental subject was also served as self-control and cephalometric analysis was conducted.

RESULTSCompared with the results of pretreatment, the distance of PNS-Ba, SPP-SPPW, P-T, V-LPW and the Mcnamara line increased remarkably.

CONCLUSIONThe Fränkel II appliance can improve the sagittal dimensions of the upper airway in children.

Cephalometry ; Child ; Female ; Humans ; Male ; Malocclusion, Angle Class II ; pathology ; therapy ; Orthodontic Appliances, Functional ; Orthodontics, Corrective ; instrumentation ; Pharynx ; anatomy & histology ; Radiography ; Respiratory System ; anatomy & histology ; Skull ; diagnostic imaging

Long-segment tracheal stenosis in infants and small children is difficult to manage and can be life-threatening. A retrospective review of 12 patients who underwent surgery for congenital tracheal stenosis between 1996 and 2004 was conducted. The patients' median age was 3.6 months. All patients had diffuse tracheal stenosis involving 40-61% (median, 50%) of the length of the trachea, which was suspected to be associated with complete tracheal ring. Five patients had proximal bronchial stenosis also. Ten patients had associated cardiac anomalies. Three different techniques were performed; pericardial patch tracheoplasty (n=4), tracheal autograft tracheoplasty (n=6), and slide tracheoplasty (n=2). After pericardial tracheoplasty, there were 2 early and 2 late deaths. All patients survived after autograft and slide tracheoplasty except one who died of pneumonia one year after the autograft tracheoplasty. The duration of ventilator support was 6-40 days after autograft and 6-7 days after slide tracheoplasty. The duration of hospital stay was 13-266 days after autograft and 19-21 days after slide tracheoplasty. Repeated bronchoscopic examinations were required after pericardial and autograft tracheoplasty. These data demonstrate that pericardial patch tracheoplasty show poor results, whereas autograft or slide tracheoplasty gives excellent short- and long-term results.
Body Weight ; Female ; Follow-Up Studies ; Humans ; Infant ; Infant, Newborn ; Length of Stay ; Male ; Pulmonary Artery/pathology ; Respiratory System Abnormalities/surgery ; Thoracic Surgical Procedures ; Trachea/anatomy & histology ; Tracheal Stenosis/*congenital/*surgery ; Treatment Outcome

OBJECTIVETo investigate the upper airway structure of sleep-disordered breathing children.

METHODSSeventy three children with obstructive sleep apnea hypopnea syndrome (OSAHS), 53 children with primary snoring (PS) and 40 control subjects underwent pharyngeal magnetic resonance imaging (MRI). Upper airway structure images were analyzed and measured.

RESULTSThe cross-section area of the nasopharyngeal and palatopharyngeal airway in subjects with OSAHS and PS are smaller (P < 0.01) than that of the control group. The cross section area of OSAHS patients are smaller than that of PS subjects (P < 0.01). The above parameter of oropharyngeal airway in OSAHS patients is smaller than that of control group (P < 0.01), but no statistic difference compared with that of PS subjects. The cross-section area and length of the adenoid in OSAHS group are bigger and longer than that of PS group (P < 0.01) and bilateral tonsils are larger (P < 0.01); in OSAHS patients the cross-section area of the soft palate is larger and the length of the soft palate is longer (P < 0.01) than that of PS group, while this parameter of PS group is similar to that of the control group. And the maximum width of the soft palate, the cross-section area of bilateral fat pad, bilateral pterygoid and tongue are similar among OSAHS, PS and the control group. The skeletal measurement: the length of H-C2C3 in subjects with OSAHS is longer (P < 0.01); The angle(alpha) in OSAHS patients is smaller (P < 0.01) than that of other 2 groups. The angle (beta), the cross-section area of the mandible, the spine-clivus oblique, the length of the hard palate and the distance of the mandible are similar among the three groups.

CONCLUSIONSIn children with OSAHS or PS, the upper airway is restricted by both the adenoid and tonsils; however, the soft palate is also larger in OSAHS, adding further restriction. Otherwise, downward movement of the hyoid bone and decreasing of the angle (alpha) in OSAHS influence laryngopharynx airway. MRI is of clinical significance for evaluating OSAHS children's upper airway.

Case-Control Studies ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Magnetic Resonance Imaging ; Oropharynx ; pathology ; Palatine Tonsil ; pathology ; Pharynx ; pathology ; Respiratory System ; anatomy & histology ; Sleep Apnea, Obstructive ; pathology ; Snoring ; pathology