Dynamic Tracheal Collapse Research Articles

Dynamic tracheal collapse in a wagyu calf with multiple rib fractures after dystocia

A dynamic tracheal collapse caused by multiple rib fractures in a neonatal wagyu calf was diagnosed by radiography, endoscopy and computed tomography. Conservative treatment, consisting of the medical treatment of respiratory inflammation and the reduction of environmental and social stress was initiated. The respiratory signs improved significantly, and the calf was discharged. The condition deteriorated after several weeks without treatment, most likely due to of excessive callus formation of the fractured ribs causing increased reduction in tracheal diameter.

Gender differences in association between expiratory dynamic airway collapse and severity of obstructive sleep apnea

ObjectivesRepetitive unbalances and tensions generated by inspiratory efforts against an obstructive upper airway during sleep predispose the development of expiratory central airway collapse. In addition, structures of the upper airway between men and women have differences and could be the reasons for differences in obstructive sleep apnea (OSA) prevalence between genders. The present study aimed to evaluate the association between parameters of expiratory dynamic tracheal collapse measured using chest multidetector CT and objectively measured OSA severity between men and women.Materials and methodsA total of 901 participants who underwent chest CT and overnight in-home polysomnography from the Korean Genome and Epidemiology Study were cross-sectionally analyzed (women: 46.2%). The participants were divided into three groups based on OSA severity by apnea–hypopnea index (AHI). Multivariate linear regression analysis was performed to determine the effects of central airway collapse after adjustment for cardiovascular-related covariates.ResultsIn a multivariate analysis, percentages of expiratory lumen structure reductions involving area, diameter, and perimeter were associated with AHI (all p values < 0.05) and with OSA severity (moderate-to-severe OSA than no OSA: β = 3.30%, p = 0.03; β = 2.05%, p = 0.02; β = 1.97%, p = 0.02, respectively) in women, whereas men had only a greater percentage of expiratory wall thickness reduction in moderate-to-severe OSA than no OSA (β = 0.72%, p = 0.003). In addition, women with both mild OSA and moderate-to-severe OSA had higher expiratory tracheal collapse than men without OSA, and a moderate effect of sex was observed (p for interaction = 0.007).ConclusionThe expiratory dynamic tracheal collapse was independently associated with severity of OSA in women than in men.Clinical relevance statementDifferences of pharyngeal structures and inherent features of airways by genders may affect the dissimilarities in vulnerability to sleep apnea between men and women.Key Points• The expiratory dynamic tracheal collapse was independently associated with severity of OSA in women than in men.• Women with over mild OSA had higher expiratory tracheal collapse than men without OSA, and moderate effect of sex was observed.• Structural differences of airway may affect differences in susceptibility of sleep apnea between genders.

Quantitative Assessment of Regional Dynamic Airway Collapse in Neonates via Retrospectively Respiratory-Gated 1 H Ultrashort Echo Time MRI.

Neonatal dynamic tracheal collapse (tracheomalacia, TM) is a common and serious comorbidity in infants, particularly those with chronic lung disease of prematurity (bronchopulmonary dysplasia, BPD) or congenital airway or lung-related conditions such as congenital diaphragmatic hernia (CDH), but the underlying pathology, impact on clinical outcomes, and response to therapy are not well understood. There is a pressing clinical need for an accurate, objective, and safe assessment of neonatal TM. To use retrospectively respiratory-gated ultrashort echo-time (UTE) MRI to noninvasively analyze moving tracheal anatomy for regional, quantitative evaluation of dynamic airway collapse in quiet-breathing, nonsedated neonates. Prospective. Twenty-seven neonatal subjects with varying respiratory morbidities (control, BPD, CDH, abnormal polysomnogram). High-resolution 3D radial UTE MRI (0.7 mm isotropic) on 1.5T scanner sited in the neonatal intensive care unit. Images were retrospectively respiratory-gated using the motion-modulated time-course of the k-space center. Tracheal surfaces were generated from segmentations of end-expiration/inspiration images and analyzed geometrically along the tracheal length to calculate percent-change in luminal cross-sectional area (A % ) and ratio of minor-to-major diameters at end-expiration (r D,exp ). Geometric results were compared to clinically available bronchoscopic findings (n = 14). Two-sample t-test. Maximum A % significantly identified subjects with/without a bronchoscopic TM diagnosis (with: 46.9 ± 10.0%; without: 27.0 ± 5.8%; P < 0.001), as did minimum r D,exp (with: 0.346 ± 0.146; without: 0.671 ± 0.218; P = 0.008). Subjects with severe BPD exhibited a far larger range of minimum r D,exp than subjects with mild/moderate BPD or controls (0.631 ± 0.222, 0.782 ± 0.075, and 0.776 ± 0.030, respectively), while minimum r D,exp was reduced in CDH subjects (0.331 ± 0.171) compared with controls (P < 0.001). Respiratory-gated UTE MRI can quantitatively and safely evaluate neonatal dynamic tracheal collapse, as validated with the clinical standard of bronchoscopy, without requiring invasive procedures, anesthesia, or ionizing radiation. 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;49:659-667.

Thoracoscopic posterior tracheopexy for tracheomalacia: A minimally invasive technique

BackgroundTracheomalacia is the most common congenital abnormality of the trachea. Posterior tracheopexy to alleviate posterior intrusion contributing to dynamic tracheal collapse has been reported using thoracotomy or median sternotomy. Here we describe the minimally invasive operative technique of thoracoscopic posterior tracheopexy with bronchoscopic guidance. Operative techniqueAfter preoperative computed tomography and bronchoscopy, a right thoracoscopic approach is utilized. The esophagus is mobilized and the membranous trachea is sutured to the prevertebral fascia under direct bronchoscopic visualization. Immediate improvement in tracheal collapse is noted. No major complications are reported and length of stay is short. Aortopexy may also be required to address anterior vascular compression. ConclusionThoracoscopic posterior tracheopexy is safe and feasible. Further studies with more patients and longer follow-up are needed to assess durability.

Titanium plating system with autologous rib graft sternoplasty in the treatment of thoracic inlet compression

Abstract Narrowing of the thoracic inlet leading to airway compression is a rare and challenging condition in the pediatric population. Reports in the literature have described this variant related to multiple conditions including double crush phenomenon following repair of pectus excavatum, anterior spinal displacement, and straight back syndrome. Underlying genetic conditions such as Marfan's Syndrome and Hurler's Syndrome have also been reported to contribute to clinically significant airway compression independent of dynamic tracheal collapse such as tracheomalacia. The borders of the thoracic inlet are anatomically bound by the body of the first thoracic vertebrae (T1) posteriorly, the posterior surface of the manubrium anteriorly, and the medial aspects of the first ribs on either side laterally. Relief of tracheal compression in this location is complicated by the rigidity of the boney thoracic inlet and limited space for lifting procedures such as anterior aortopexy. Several operative approaches to treat this condition have been described including manubrial/sternal resection, first rib resection, and reconstruction of the thoracic inlet. Described here are three patients where successful reconstruction of the thoracic inlet was achieved using autologous rib graft sternoplasty and a titanium sternal plating system to widen the thoracic inlet and eliminate external compression on the trachea.

Dynamic tracheal collapse associated with disseminated histiocytic sarcoma in a cat

This case report describes an unusual presentation of histiocytic sarcoma in a domestic shorthair cat. Initial investigation revealed a haemodynamically insignificant hypertrophic cardiomyopathy, bronchitis and a mild irregularity of the cervical trachea. The cat's disease progressed over a two-week period. Repeat radiography and tracheoscopy revealed a marked dynamic tracheal collapse associated with a raised plaque-like lesion within the cervical trachea. Subsequent post-mortem examination and histopathology revealed disseminated histiocytic sarcoma involving the trachea and kidneys. This is the first reported case of a histiocytic sarcoma involving the trachea in either dogs or cats.

Pulmonary Edema Secondary to Dynamic Tracheal Collapse

Severe pulmonary edema can be a complication of both intra- and extrathoracic airway obstructions. We describe a unique case of pulmonary edema following expiratory dynamic collapse of the trachea. An 80-year-old woman presented with orthopnea associated with a forcible dry cough for about a week. Physical examination revealed bilateral diffuse lung crepitations. Chest radiography demonstrated bilateral pulmonary edema. However, an echocardiogram demonstrated normal biventricular size and function. Spiral CT of the chest was negative for pulmonary embolism; however, it demonstrated expiratory collapse of the posterior tracheal wall. Dynamic CT of the trachea and bronchoscopy subsequently confirmed such findings. Different cough suppressants and diuretics were tried, but with limited improvement in the patient's respiratory status. A tracheal stent was placed to support the collapsed trachea. Both the clinical and radiologic manifestations of the postobstructive pulmonary edema resolved subsequently. Pulmonary function tests done before and 3 months after stent placement demonstrated an improvement in both FEV1 and FVC. There was no recurrence of patient symptoms 3 years later. Airway obstructions should be considered in the workup of non-cardiogenic pulmonary edema. Tracheal stenting can be effective in the resolution of such edema in select patients.

Surgical management of atypical lateral tracheal collapse in a dog

A FOUR‐year‐old spayed miniature poodle was presented for evaluation because of a chronic cough which had been present from eight weeks of age. The condition had gradually worsened until exercise intolerance, inappetence and abdominal breathing occurred. The dog was thin and weighed only 1.5 kg. Auscultation revealed tachycardia, a normal respiratory rate and wheezing noises ‐ more prominent on inspiration and localised to the cervical portion of the trachea. There was marked inspiratory and expiratory effort. Tracheal sensitivity was moderate and palpation induced a dry hacking cough. Radiography demonstrated mild thickening of the bronchial wall and pulmonary hyperinflation. Expiratory/inspiratory radiographs failed to demonstrate dynamic tracheal collapse. On fluroscopy, substantial changes in tracheal calibre were not apparent. Bronchoscopy was performed and the tracheal lumen was normal up to 12.5 cm from the incisors. At this point, there was lateral tracheal collapse to about 30 per cent. There was dynamic collapse with respiratory effort. The bronchoscope could be passed beyond the narrowing (consisting of five tracheal rings) to a trachea of normal size. No pathogens were found on tracheal lavage. Surgery was undertaken through a midline, ventral approach. Six specially made tracheal ring prostheses were individually inserted around the trachea and inside the recurrent laryngeal nerve. Each prosthesis was sutured in four places to the tracheal ring, to give external support. The dog improved clinically and 11 months after surgery, bronchoscopy was again performed. The trachea was narrowed to approximately 60 per cent but there was no dynamic collapse of the airway. Twenty‐seven months after surgery the dog continued to lead a healthy active life.