Multiplanar and two-dimensional imaging of central airway stenting with multidetector computed tomography

Clinical Approach to Central Airway Obstruction in Adult Patients: Perioperative Focus on Causes and Management Including Tracheobronchial Stenting

Central airway obstruction (CAO) is a life-threatening condition associated with poor prognosis. Therapeutic bronchoscopy along with systemic therapies significantly improve survival and quality of life in patients with symptomatic benign and malignant CAO. Endoluminal therapies and tracheobronchial stenting may be used, and a multidisciplinary approach is essential for holistic management of CAO. Perioperative planning and evaluation, as well as attention to intraoperative and postoperative management are key to optimal outcomes. This review provides an overview of the etiology and clinical approach to CAO, perioperative considerations for endoluminal therapies and tracheobronchial stenting, perioperative evaluation and preparation for therapeutic bronchoscopy, and management of operative and postoperative challenges in CAO.

Tumor-Related Factors Affecting the Success of Interventional Bronchoscopy in Malignant Airway Obstructions

BACKGROUND

It is difficult to select patients who will benefit from endobronchial treatment (ET) in malignant central airway obstruction (MCAO). We aimed to determine the tumor-related factors that affect the success of MCAO treatment.

METHODS

ETs for MCAO between March 2019 and June 2021 were analyzed retrospectively. The relationships between the success of the procedure and the percentage of endoluminal obstruction, tumor size, and type of lesion were evaluated.

RESULTS

Totally, 220 ETs were administered to 205 patients. Treatment was significantly more successful for the patients with pure endobronchial lesions than those with mixed lesions. The success rate was significantly lower when the tumor size was greater than 54.5 mm and the degree of endoluminal stenosis exceeded 92%; the area under the curve was 0.734 (0.625-0.842; P=0.001) and 0.733 (0.597- 0.870; P=0.001), respectively. There was no difference in the procedural success between lung cancer and extrathoracic malignancies and tumor treatment before the procedure.

CONCLUSION

Mixed lesions, tumor size over 54.5 mm, and a degree of stenosis over 92% are risk factors for unsuccessful endoluminal obstruction procedures. These parameters should be considered when selecting patients for ET interventions.

COMPARISON OF FLUOROSCOPY AND COMPUTED TOMOGRAPHY FOR TRACHEAL LUMEN DIAMETER MEASUREMENT AND DETERMINATION OF INTRALUMINAL STENT SIZE IN HEALTHY DOGS

Tracheal collapse is a progressive airway disease that can ultimately result in complete airway obstruction. Intraluminal tracheal stents are a minimally invasive and viable treatment for tracheal collapse once the disease becomes refractory to medical management. Intraluminal stent size is chosen based on the maximum measured tracheal diameter during maximum inflation. The purpose of this prospective, cross-sectional study was to compare tracheal lumen diameter measurements and subsequent selected stent size using both fluoroscopy and CT and to evaluate inter- and intraobserver variability of the measurements. Seventeen healthy Beagles were anesthetized and imaged with fluoroscopy and CT with positive pressure ventilation to 20 cm H2 O. Fluoroscopic and CT maximum tracheal diameters were measured by three readers. Three individual measurements were made at eight predetermined tracheal sites for dorsoventral (height) and laterolateral (width) dimensions. Tracheal diameters and stent sizes (based on the maximum tracheal diameter + 10%) were analyzed using a linear mixed model. CT tracheal lumen diameters were larger compared to fluoroscopy at all locations (P-value < 0.0001). When comparing modalities, fluoroscopic and CT stent sizes were statistically different. Greater overall variation in tracheal diameter measurement (height or width) existed for fluoroscopy compared to CT, both within and among observers. The greater tracheal diameter measured with CT and lower measurement variability has clinical significance, as this may be the imaging modality of choice for appropriate stent selection to minimize complications in veterinary patients.

Is there a correlation between right bronchus length and diameter with age?

OBJECTIVE

Right main bronchial anatomy knowledge is essential to guide endoscopic stent placement in modern era. The aim is to describe right bronchial anatomy, cross-area and its relation with the right pulmonary artery and patient's age.

METHODS

One hundred thirty four cadaveric specimens were studied after approval by the Research and Ethics Committee at the University of São Paulo Medical School and Medical Forensic Institute of São Paulo. All necropsies were performed in natura after 24 hours of death and patients with previous pulmonary disease were excluded. Landmarks to start measurement were the first tracheal ring, vertex of carina, first right bronchial ring, and right pulmonary artery area over the right main bronchus. After mobilization, the specimens were measured using a caliper and measurement of distances was recorded in centimeters at landmarks points. All the measures (distances, cross sectional area and planes) were performed by three independent observers and recorded as mean, standard error and ranges. Student t test was used to compare means and linear regression was applied to correlate the measurements.

RESULTS

From 134 specimens studied, 34 were excluded (10 with previous history of pulmonary diseases, surgery or deformities and 24 of female gender). Linear regression showed proportionality between tracheal length and right bronchus length; with the area at first tracheal ring and carina and also between the cross sectional area at these points. Linear regression analysis between tracheal length and age (R=0.593 P<0.005), right bronchus length and age (R=0.523, P<0.005), area of contact between right bronchus and right pulmonary artery and age (R=0.35, P<0.005).

CONCLUSIONS

We can conclude that large airways grow progressively with increasing age in male gender. There was a direct correlation between age and tracheal length; as has age and right bronchus length. There was a direct correlation between age and the area of the right bronchus covered by the right pulmonary artery.