Tumoral and non-tumoral trachea stenoses: evaluation with three-dimensional CT and virtual bronchoscopy

<p>Abstract</p> <p>Background</p> <p>We evaluated the ability of 3D-CT and virtual bronchoscopy to estimate trachea stenosis in comparison to conventional axial CT and fiberoptic bronchoscopy, with a view to assist thoracic surgeons in depicting the anatomical characteristics of tracheal strictures.</p> <p>Methods</p> <p>Spiral CT was performed in 16 patients with suspected tracheal stenoses and in 5 normal subjects. Tracheal stenoses due to an endoluminal neoplasm were detected in 13 patients, whilst post-intubation tracheal stricture was observed in the other 3 patients. Multiplanar reformatting (MPR), volume rendering techniques (VRT) and virtual endoscopy (VE) for trachea evaluation were applied and findings were compared to axial CT and fiberoptic bronchoscopy. The accuracy of the procedure in describing the localization and degree of stenosis was tested by two radiologists in a blinded controlled trial.</p> <p>Results</p> <p>The imaging modalities tested showed the same stenoses as the ones detected by flexible bronchoscopy and achieved accurate and non-invasive morphological characterization of the strictures, as well as additional information about the extraluminal extent of the disease. No statistically significant difference was observed between the bronchoscopic findings and the results of axial CT estimations (P = 1.0). No statistically significant differences were observed between bronchoscopic findings and the MPR, VRT and VE image evaluations (P = 0.705, 0.414 and 0.414 respectively).</p> <p>Conclusion</p> <p>CT and computed generated images may provide a high fidelity, noninvasive and reproducible evaluation of the trachea compared to bronchoscopy. They may play a role in assessment of airway patency distal to high-grade stenoses, and represent a reliable alternative method for patients not amenable to conventional bronchoscopy.</p

Evaluation of tracheal stenosis: comparison between computed tomography virtual tracheobronchoscopy with multiplanar reformatting, flexible tracheofiberoscopy and intra-operative findings

The aim of the study was to evaluate and compare various helical CT display modes [virtual endoscopy (VE)] and multiplanar reformations (MPR), conventional flexible tracheobronchoscopy (FT) and intra-operative (IO) findings in patients with tracheal stenosis and to analyze the advantage of MPR and VE in diagnosis and treatment planning and in postoperative follow-up. Thirty-seven patients with tracheal stenosis underwent standard neck and chest CT followed by MPR and VE. Results were correlated with the results of FT and IO findings. Thirty-three of the 37 stenoses were correctly graded and measured adequately using VE. Complete correlation among CT, fiberoptic tracheoscopy, and surgery of stenosis grading, stenosis length and length of planned resection segment of the trachea was noted between 33 of 37 patients with tracheal stenosis. Correlation between VE and IO was noted in 35 of 37 patients and between FT and VE was noted in 33 of 37 patients with tracheal stenosis. The sensitivity of VE was 94–97%, specificity was 100% with comparison to IO findings. The sensitivity and accuracy of MPR was 86–89% and specificity was 100% with comparison to FT findings. The results of the study indicate that VE is an excellent, consistent, and objective technique. VE with MPR is very useful in diagnostic evaluation and treatment planning in patients with tracheal stenosis

Agreement Among Radiographs, Fluoroscopy and Bronchoscopy in Documentation of Airway Collapse in Dogs.

BackgroundAirway collapse is a common finding in dogs with chronic cough, yet the diagnosis can be difficult to confirm without specialty equipment.HypothesisBronchoscopic documentation of tracheobronchial collapse will show better agreement with fluoroscopic imaging than with standard radiography.AnimalsForty-two dogs prospectively evaluated for chronic cough.MethodsIn this prospective study, three-view thoracic radiographs were obtained followed by fluoroscopy during tidal respiration and fluoroscopy during induction of cough. Digital images were assessed for the presence or absence of collapse at the trachea and each lobar bronchus. Bronchoscopy was performed under general anesthesia for identification of tracheobronchial collapse at each lung segment. Agreement of imaging tests with bronchoscopy was evaluated along with sensitivity and specificity of imaging modalities as compared to bronchoscopy.ResultsAirway collapse was identified in 41/42 dogs via 1 or more testing modalities. Percent agreement between pairs of tests varied between 49 and 87% with poor-moderate agreement at most bronchial sites. Sensitivity for the detection of bronchoscopically identified collapse was highest for radiography at the trachea, left lobar bronchi, and the right middle bronchus, although specificity was relatively low. Detection of airway collapse was increased when fluoroscopy was performed after induction of cough compared to during tidal respiration.ConclusionsRadiography and fluoroscopy are complementary imaging techniques useful in the documentation of bronchial collapse in dogs. Confirming the presence or absence of tracheal or bronchial collapse can require multiple imaging modalities as well as bronchoscopy

Image Registration to Map Endoscopic Video to Computed Tomography for Head and Neck Radiotherapy Patients

The purpose of this work was to explore the feasibility of registering endoscopic video to radiotherapy treatment plans for patients with head and neck cancer without physical tracking of the endoscope during the examination. Endoscopy-CT registration would provide a clinical tool that could be used to enhance the treatment planning process and would allow for new methods to study the incidence of radiation-related toxicity. Endoscopic video frames were registered to CT by optimizing virtual endoscope placement to maximize the similarity between the frame and the virtual image. Virtual endoscopic images were rendered using a polygonal mesh created by segmenting the airways of the head and neck with a density threshold. The optical properties of the virtual endoscope were matched to a calibrated model of the real endoscope. A novel registration algorithm was developed that takes advantage of physical constraints on the endoscope to effectively search the airways of the head and neck for the desired virtual endoscope coordinates. This algorithm was tested on rigid phantoms with embedded point markers and protruding bolus material. In these tests, the median registration accuracy was 3.0 mm for point measurements and 3.5 mm for surface measurements. The algorithm was also tested on four endoscopic examinations of three patients, in which it achieved a median registration accuracy of 9.9 mm. The uncertainties caused by the non-rigid anatomy of the head and neck and differences in patient positioning between endoscopic examinations and CT scans were examined by taking repeated measurements after placing the virtual endoscope in surface meshes created from different CT scans. Non-rigid anatomy introduced errors on the order of 1-3 mm. Patient positioning had a larger impact, introducing errors on the order of 3.5-4.5 mm. Endoscopy-CT registration in the head and neck is possible, but large registration errors were found in patients. The uncertainty analyses suggest a lower limit of 3-5 mm. Further development is required to achieve an accuracy suitable for clinical use

The role of posterior aortopexy in the treatment of left mainstem bronchus compression

OBJECTIVES: We reviewed the role of posterior aortopexy for left mainstem bronchus compression in infants and children. METHODS: Eighteen children with respiratory symptoms were enrolled between 2005 and 2015 for surgical decompression of the left mainstem bronchus. The children were managed from diagnosis to follow-up by a dedicated tracheal team. Primary outcomes were the complete relief of symptoms or improvement with respect to preoperative clinical status. RESULTS: The median age was 4 years (0.3-15.4) and the median weight was 13.2 kg (3, 1-40). Symptoms or indications for bronchoscopy included difficult weaning from mechanical ventilation (n = 3, 17%), difficult weaning from tracheotomy (n = 4, 22%), recurrent pneumonia (n = 4, 22%), wheezing (n = 3, 17%), atelectasis (n = 1, 5.5%), bitonal cough (n = 1, 5.5%) and stridor (n = 2, 11%). Associated malformations were present in 88.7%. The diagnosis was made by bronchoscopy and computed tomography. Indication for surgery was the presence of pulsations and reduction in the diameter of the left mainstem bronchus compression of more than 70%. Surgery was performed by left posterolateral thoracotomy. Aortopexy was done under bronchoscopic control. No early or late deaths were observed, nor were reoperations necessary. Residual malacia was observed in 8 children (44%). Median follow-up was 4.1 years (0.1-7.1). At last follow-up, 17/18 (94.4%) children showed adequate airway patency. CONCLUSIONS: The intrathoracic location of the left mainstem bronchus predisposes it to compression. Vascular anomalies represent the most frequent causes. Aortopexy has been advocated as a safe and useful method to relieve the compression, and our results confirmed these findings. Management of these patients is challenging and requires a multidisciplinary team

Virtual Bronchoscopy and 3D Spiral CT Reconstructions in the Management of Patient with Bronchial Cancer – Our Experience with Syngo 3D Postprocessing Software

Multislice helical CT generated virtual bronchoscopy (VB) represents one of the most recent developments in three-dimensional computer aided visualisation techniques. VB allows non-invasive and relatively accurate 3D evaluation of tracheobronchal tree. We performed virtual bronchoscopy and in-space 3D volume analysis on CT-data set acquired from sixty-four-year old male with bronchial cancer in order to demonstrate advantages and disadvantages of these methods in diagnostics and preoperative management of metastatic bronchial cancer. Siemens Somatom Emotion 16 helical CT scanner was used for data acquisition. Data post-processing was done with 3D Syngo 2006G software package from Siemens medical systems. CT scanning of the thorax was performed in heavy smoker with an expansive T4N1M1 malignant process in a superior lobe of the right lung accompanied with large metastatic lesion attached on the right lateral chest wall. Metastatic lesions were also found in vertebral column. In-space 3D analysis followed with virtual bronchoscopy had revealed obstruction of apical branch of superior lobe segmental bronchus. External compression done by tumor to the superior segmental and right main bronchus was found. We concluded that multi-slice CT in connection with VB became a possible non-invasive alternative to bronchoscopy, if tissue samples are not required

Imaging and Endoscopic Diagnosis of Lung Diseases in Small Animals. A Review

Diagnostic imaging plays a fundamental role in the diagnosis of pulmonary diseases. Radiography, ultra-sound, computed tomography, and endoscopy are important tools for achieving a diagnosis. The choice of diagnostic procedure varies according to the patient, the suspected diagnosis and the risk/benefit ratio. Cul-ture, cytology and histology are nearly always necessary to obtain a definitive diagnosis. Several biopsy sam-pling techniques are described. Surgical biopsies are the gold standard for the diagnosis of bronchiolitis or interstitial lung diseases but often not performed due to the high risk. In humans, the introduction of trans -bronchial cryobiopsies has led to excellent results in the study of interstitial lung diseases. (c) 2022 Elsevier Inc. All rights reserved