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61.
《Medical image analysis》2014,18(7):963-976
Airway deformation and stenosis can be key signs of pathology such as lymphadenopathy. This study presents a local airway point distribution model (LA-PDM) to automatically analyse regions of the airway tree in CT scans and identify abnormal airway deformation. In our method, the airway tree is segmented and the centreline identified from each chest CT scan. Thin-plate splines, along with a local mesh alignment method for tubular meshes, are used to register the airways and develop point distribution models (PDM). Each PDM is then used to analyse and classify local regions of the airway. This LA-PDM method was developed using 89 training cases and evaluated on a 90 CT test set, where each set includes paediatric tuberculosis (TB) cases (with airway involvement) and non-TB cases (without airway involvement). The LA-PDM was able to accurately distinguish cases with airway involvement with an AUC of the ROC classification (and 95% confidence interval) of 0.87 (0.77–0.94) for the Trachea–LMB–RMB region and 0.81 (0.68–0.90) for the RMB–RUL–BI region – outperforming a comparison method based on airway cross-sectional features. This has the potential to assist and improve airway analysis from CT scans by detecting involved airways and visualising affected airway regions. 相似文献
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《Journal of cranio-maxillo-facial surgery》2014,42(7):1122-1127
Pierre Robin sequence (PRS) is a congenital abnormality that may cause upper airway obstruction requiring surgical intervention. This preliminary study aimed to examine the feasibility and effectiveness of mandible traction with wires for the treatment of upper airway obstruction caused by PRS in Chinese infants. Measures of interest included transcutaneous oxygen saturation before and after surgery, duration of surgery and traction, complications, and CT findings. Seven infants were included in the study (mean birth weight: 2485 g, range: 2405–2570 g); four were born preterm and three were born full term. Mean age at surgery was 13.7 days (range: 2–28 days), mean duration of surgery was 16.6 min (range: 13–25 min) and mean duration of traction was 26.6 days (range: 21–35 days). Mean follow-up was 6.2 months (range: 1–11 months). No infant experienced severe complications. All infants experienced increases in transcutaneous oxygen saturation after surgery. Mean transcutaneous oxygen saturation was 82% before surgery and 98% after surgery. Follow-up morphology of the mandible was excellent. There was no upper airway obstruction, and short-term growth and development were satisfactory. These preliminary findings suggest that mandibular traction with wires may be an effective treatment for upper airway obstruction caused by PRS in Chinese infants. 相似文献
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《COPD》2013,10(2):133-140
ABSTRACTPatients with chronic obstructive pulmonary disease (COPD) demonstrate airway hyperresponsiveness to a number of indirect stimuli. Hyperresponsiveness to cold air hyperventilation, exercise, and drugs like propranalol and methoxamine seem to be able to distinguish patients with COPD from those with asthma, whereas hyperresponsiveness to stimuli like adenosine 5-monophosphate (AMP) and hypertonic saline seem unable to do so. The relationship of airway responsiveness to indirect stimuli and airway inflammation has received little study. The clinical relevance of hyperresponsiveness to an indirect challenge, including the impact on the natural history, relation to types of bronchitis, baseline airway calibre, and response to treatment need to be studied. 相似文献
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Geoffrey R. Ferril Henry P. Barham Jeremy D. Prager 《International journal of pediatric otorhinolaryngology》2014
1p36 deletion syndrome comprises a phenotypic presentation that includes central nervous system, cardiac, and craniofacial anomalies. There has been no report of associated airway anomalies with this syndrome. We present here a case report and literature review. Prenatally, amniocentesis for chromosomal analysis was performed on our patient, with results consistent with 1p36 deletion syndrome. Respiratory distress and unsuccessful attempts at intubation prompted transfer to Children's Hospital of Colorado. Microlaryngoscopy was subsequently performed, revealing a persistent buccopharyngeal membrane and unidentifiable larynx. Emergent tracheostomy was then performed to secure the airway. Airway anomalies may be associated with 1p36 deletion syndrome. 相似文献
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Julio E. González-Aguirre Claudia Paola Rivera-Uribe Erick Joel Rendón-Ramírez Rogelio Cañamar-Lomas Juan Antonio Serna-Rodríguez Roberto Mercado-Longoría 《Archivos de bronconeumologia》2019,55(4):195-200
Introduction
Invasive respiratory support is a cornerstone of Critical Care Medicine, however, protocols for withdrawal of mechanical ventilation are still far from perfect. Failure to extubation occurs in up to 20% of patients, despite a successful spontaneous breathing trial (SBT).Methods
We prospectively included ventilated patients admitted to medical and surgical intensive care unit in a university hospital in northern Mexico. At the end of a successful SBT, we measured diaphragmatic shortening fraction (DSF) by the formula: diaphragmatic thickness at the end of inspiration – diaphragmatic thickness at the end of expiration/diaphragmatic thickness at the end of expiration × 100, and the presence of B-lines in five regions of the right and left lung. The primary objective was to determine whether analysis of DSF combined with pulmonary ultrasound improves prediction of extubation failure.Results
Eighty-two patients were included, 24 (29.2%) failed to extubation. At univariate analysis, DSF (Youden's J: >30% [sensibility and specificity 62 and 50%, respectively]) and number of B-lines regions (Youden's J: >1 zone [sensibility and specificity 66 and 92%, respectively]) were significant related to extubation failure (area under the curve 0.66 [0.52–0.80] and 0.81 [0.70–0.93], respectively). At the binomial logistic regression, only the number of B-lines regions remains significantly related to extubation failure (OR 5.91 [2.33–14.98], P < .001).Conclusion
In patients with a successfully SBT, the absence of B-lines significantly decreases the probability of extubation failure. Diaphragmatic shortening fraction analysis does not add predictive power over the use of pulmonary ultrasound. 相似文献69.
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