Boyden's triad in the left lung: an interesting phenomenon.

OBJECTIVES: Boyden's triad of the right lung was first proposed in 2021. Here, we report 5 cases of this malformation found in the left lung. METHODS: A total of 5280 patients with pulmonary lesions underwent three-dimensional computed tomography bronchography and angiography between January 2019 and January 2021, prior to surgery; 5 cases of this malformation were identified in the left lung. Bronchovascular patterns were analysed in each patient. RESULTS: The incidence rate of Boyden's triad in the left lung was 0.1%. This malformation was further divided into B3 on B4+5 type and B3 on B4 type. In B3 on B4+5 type, B3 was shifted downwards on the common trunk of B4+5, and A3 arose from the common trunk of A4+5 running alongside B3. In B3 on B4 type, B3 was shifted downwards on B4. A4 and A5 appeared separately. A3 arose from A4, running alongside B3; A5 arose from the common trunk of A8 - 10, and there was also an extraordinary 'posterior vein' (V. post): V1+2c. The incidence of V. post was 0.17%. An additional 'fissure' lies longitudinally between S1+2 and S3+4+5, nearly perpendicular to the oblique fissure, dividing the upper lobe into 'two lobes'. CONCLUSIONS: The B3 downwards-shifting malformation can be found on both lungs, and this is the first description of Boyden's triad in the left lung; it appears to be much rarer than that in the right lung, with some accompanying unique variations.

Thoracoscopic Anatomic Left Lower Lobe S6b Subsegmentectomy.

Although thoracoscopic lung segmentectomy has made significant achievements, there is little known about how to perform subsegmentectomy, which can also acquire a safe margin for curability but with more pulmonary volume reserved. This report presents the surgical procedure for subsegmental anatomic resection of left lower lobe subsegment 6b guided by the simulation of bronchovascular branching through the use of 3-dimensional computed tomographic bronchography and angiography.

Boyden's triad: the past, present and future.

OBJECTIVES: The B3 downwards-shifting malformation was first proposed by Boyden in 1950. Here, we report 14 cases of this malformation in the right lung and the first case of segmentectomy for this malformation. METHODS: All patients with pulmonary lesions underwent three-dimensional computed tomography bronchography and angiography (3D-CTBA) between January 2019 and January 2020, prior to surgery. A consecutive 2356 patients were included, and 14 cases of this malformation were identified; bronchovascular patterns were analysed in each patient. RESULTS: The incidence of this malformation was 0.6%. It was further divided into 3 types: over downwards-shift, partial downwards-shift and normal downwards-shift. The normal downwards-shift type was the most common (8/14), where B3 shifted downwards completely to merge with B4 + 5. In the partial downwards-shift (5/14), only part of the B3 shifted. In the over downwards-shift type (1/14), both B3 and B1b shifted downwards. A bifurcated right upper lobe （RUL) bronchus (B1 defective) was observed in 3 cases. The incidence of V1a, V1b, V2a, V2b, V2c, V3a, V3b and V3c was 100% (14/14). The incidence rates of A1, A3a and A3b were 100% (14/14). The incidence of A2 rec and A2 asc was 92.9% (13/14) and 71.4% (10/14), respectively. CONCLUSIONS: The B3 downwards-shifting malformation or 'Boyden's triad' is a rare anomaly. Anatomical exploration of this malformation is important for surgery.

Modified left subsuperior segmentectomy via 2-cm uniportal video-assisted thoracoscopic surgery.

Independent subsuperior segmentectomy (S*) via uniportal video-assisted thoracoscopic surgery (VATS) has rarely been reported. We describe our modified technique of performing simplified left subsuperior segmentectomy for a lung nodule, via 2-cm uniportal VATS. The uniportal approach was different from the traditional approach made by blunt separation into the thorax without electrocautery. Our modified technique minimizes damage to the intercostal nerves and muscles. We also simplified the subsuperior segmentectomy procedure according to the findings of three-dimensional (3D) computed tomography angiography and bronchography. Combining these two techniques achieves a new more minimally invasive method for subsuperior segmentectomy.

The value of the air bronchogram sign on CT image in the identification of different solitary pulmonary consolidation lesions.

The aim of the present study is to investigate the value of air bronchogram sign on computed tomography (CT) image in the differential diagnosis of solitary pulmonary consolidation lesions (SPLs).A total of 105 patients (including 39 cases of lung cancer, 43 cases of tuberculosis, and 23 cases of pneumonia) with SPLs were evaluated for the CT features of air bronchogram sign in this retrospective study. The shape and lumen of the bronchi with air bronchogram sign, the length of the involved bronchus with air bronchogram sign, the length of lesion on the same plane and direction, and the ratio between the length of the involved bronchus and that of the lesion were evaluated.In total, there were 172 segmental and subsegmental bronchi involved. There were 62 segmental and subsegmental bronchi involved among 39 lung cancer cases, 77 segmental and subsegmental bronchi involved among 43 tuberculosis cases, and 33 segmental and subsegmental bronchi involved among 23 pneumonia cases. The shape of the bronchi with air bronchogram sign was significantly different among lung cancer, tuberculosis, and pneumonia (P < .05). The lumen of the bronchi with air bronchogram sign was also significantly different among the 3 SPLs (P < .05). The length of the involved bronchus with air bronchogram sign and the ratio between the length of the involved bronchus and that of the lesion were significantly different between lung cancer and tuberculosis (P < .05), or between lung cancer and pneumonia (P < .05), but not between tuberculosis and pneumonia (P > .05). No significant difference was found in the length of lesion among the 3 SPLs (P > .05).The shape and lumen of the bronchi with air bronchogram sign can be used to distinguish lung cancer, tuberculosis, and pneumonia. The length of the involved bronchus with air bronchogram sign and the ratio between the length of the involved bronchus and that of the lesion can be used to distinguish lung cancer from tuberculosis and pneumonia.

Selective Management of Multiple Bronchopleural Fistulae in a Pediatric Patient on Extracorporeal Membrane Oxygenation: A Multidisciplinary Approach.

INTRODUCTION: This case highlights the successful utilization of a multidisciplinary approach to numerous bilateral bronchopleural fistulae (BPF) using minimally invasive techniques. In this study, we present a previously healthy 14-year-old male hospitalized with 2009 H1N1 influenza and methicillin-resistant Staphylococcus aureus coinfection complicated by severe acute respiratory distress syndrome and multifocal necrotizing pneumonia, with significant lung tissue damage requiring prolonged extracorporeal membrane oxygenation (ECMO) support. METHODS: The development of multiple BPFs precluded lung recruitment necessary to wean from ECMO. Treatment options were very limited and endobronchial valves were considered. However, localizing single airleaks with a fogarty balloon is normally the technique to determine appropriate location to place the valves. With multiple fistulae, this technique would be ineffective. Therefore, the patient was brought to interventional radiology and bronchography was performed for selective fistula mapping. With this precise localization, the multiple fistulae were ultimately controlled using image-guided embolization and the placement of multiple endobronchial valves. The success of this intervention enabled positive pressure ventilator support and rehabilitation required for weaning from ECMO support. CONCLUSION: This case highlights the successful utilization of a multidisciplinary approach to numerous bilateral BPFs using minimally invasive techniques.

Air bronchogram in pleomorphic carcinoma of the lung is associated with favorable prognosis.

BACKGROUND: Pleomorphic carcinoma (PC) of the lung is a rare histological type of lung carcinoma. The association between computed tomography (CT) findings and histology with outcome remains unclear. We examined the relationships between CT features and histopathologic findings, and evaluated the impact of CT features and other clinicopathologic factors on survival. METHODS: Thirty-five consecutive patients with PC of the lung who underwent surgery between October 2010 and December 2015 were enrolled in this study. The 35 tumors were classified with or without air bronchogram in the tumors, and with or without intratumoral ground glass opacity (GGO) on CT. RESULTS: Air bronchogram and GGO were detected in 12 (34.3%) and 5 (14.3%) tumors, respectively. Multivariate analysis revealed that air bronchogram was significantly associated with the presence of adenocarcinoma components with lepidic growth patterns (P = 0.005), and predominance of adenocarcinomas (P = 0.026). GGO was significantly associated with the presence of adenocarcinoma component with lepidic growth pattern (P = 0.010). Air bronchogram was an independent favorable prognostic factor for overall survival, whereas GGO did not have a significant effect on survival. CONCLUSION: Air bronchogram observed in PCs of the lung is strongly related with histological components of the tumor and favorable outcome.

Thoracoscopic Medial-Basal Segment Segmentectomy.

The technical details and anatomic features of medial-basal segment (S7) segmentectomy have not been reported. We report here thoracoscopic S7 segmentectomy and S7a subsegmentectomy and explain the anatomic knowledge necessary to perform S7 segmentectomy, especially the importance of recognizing bronchus (B7) branching patterns before surgery.

Thoracoscopic Subsuperior Segment Segmentectomy.

To date, anatomic subsuperior segment (S∗) segmentectomy has not yet been reported. Herein we report the technical details of thoracoscopic anatomic S∗ segmentectomy and the anatomic features of the S∗.

Analysis of variation in bronchovascular pattern of the right middle and lower lobes of the lung using three-dimensional CT angiography and bronchography.

OBJECTIVES: General thoracic surgeons must be familiar with anatomical variation in the pulmonary vessels and bronchi. Here, we analyzed the bronchovascular pattern of the right middle lobe (RML) and right lower lobe (RLL) of the lung using three-dimensional CT angiography and bronchography (3DCTAB). METHODS: We reviewed the anatomical patterns of the pulmonary vessels and bronchi in 270 patients using 3DCTAB images. RESULTS: The branching patterns of vessels and bronchi of RML and S6 were classified according to the number of stems. The single-stem type was the most common, except in the artery of the RML, for which the two-stem type was the most common. The artery and bronchus of S*, which is an independent segment between S6 and S10, were observed in 20.4% of cases. The branching pattern of A7 (B7) was classified into four types. The A7a (B7a) type was observed in 74.8% of cases, and was the most common. The branching pattern of the artery and bronchus of S8-10 was classified into five and three types, respectively. The A8 and A9 + A10 type, and the B8 and B9 + B10 type, were observed in 68.1 and 80.4% of cases, respectively, and were the most common types. The branching pattern of V8-10 was more complex than that of A8-10 and B8-10. CONCLUSION: We explored the bronchovascular patterns of RML and RLL and their frequencies using a large number of 3DCTAB images. Our data can be used by thoracic surgeons to perform safe and precise lung resections.

Tracheobronchomalacia diagnosed by tracheobronchography in ventilator-dependent infants.

BACKGROUND: Tracheobronchomalacia prevalence in premature infants on prolonged mechanical ventilation is high. OBJECTIVE: To examine the prevalence of tracheobronchomalacia diagnosed by tracheobronchography in ventilator-dependent infants, and describe the demographic, clinical and dynamic airway characteristics of those infants with tracheobronchomalacia. MATERIALS AND METHODS: This retrospective review studies 198 tracheobronchograms performed from 1998 to 2011 in a cohort of 158 ventilator-dependent infants <2 years of age. Dynamic airway assessment during tracheobronchography determined the optimal positive end-expiratory pressure to maintain airway patency at expiration in those infants with tracheobronchomalacia. RESULTS: Tracheobronchograms were performed at a median age of 52 weeks post menstrual age. The primary diagnoses in these infants were bronchopulmonary dysplasia (53%), other causes of chronic lung disease of infancy (28%) and upper airway anomaly (13%). Of those with bronchopulmonary dysplasia, 48% had tracheobronchomalacia. Prematurity (P=0.01) and higher baseline - pre-tracheobronchogram positive end-expiratory pressure (P=0.04) were significantly associated with tracheobronchomalacia. Dynamic airway collapse during tracheobronchography showed statistically significant airway opening at optimal positive end-expiratory pressure (P < 0.001). There were no significant complications noted during and immediately following tracheobronchography. CONCLUSION: The overall prevalence of tracheobronchomalacia in this cohort of ventilator-dependent infants is 40% and in those with bronchopulmonary dysplasia is 48%. Infants born prematurely and requiring high pre-tracheobronchogram positive end-expiratory pressure were likely to have tracheobronchomalacia. Tracheobronchography can be used to safely assess the dynamic function of the airway and can provide the clinician the optimal positive end-expiratory pressure to maintain airway patency.

Using air bronchograms on multi-detector CT to predict the invasiveness of small lung adenocarcinoma.

PURPOSE: To investigate the prevalence of multidetector CT (MDCT) air bronchograms and their value in predicting the invasiveness of lung adenocarcinomas. METHODS: MDCT scans of 606 nodules in 582 patients with a lung adenocarcinoma less than 2cm in diameter confirmed by surgery and pathology were reviewed. Air bronchograms were classified into three patterns: type I, bronchus with intact lumen; type II, bronchus with dilated or tortuous lumen; and type III, bronchus with obstructed lumen. RESULTS: Air bronchograms were demonstrated on MDCT in 210 of 606 (34.7%) lung adenocarcinomas with 16.6% (35/211) preinvasive lesions (PL), 30.5% (50/164) minimally invasive adenocarcinoma (MIA), and 54.1% (125/231) invasive adenocarcinoma (IAC) (P=0.000); 18.3% (44/240) pure ground-glass nodules (GGNs), 44.2% (137/310) mixed GGNs, and 51.8% (29/56) solid nodules (P=0.000). Type I was slightly more common in MIA (36/164, 22.0%) than IAC (40/231, 17.3%) and PL (30/211, 14.2%) but without differences among them (P=0.147). Type II (PL: 5/211, 2.4%; MIA: 13/164, 7.9%; IAC: 53/231, 22.9%) and type III (PL: 0/211; MIA: 1/164, 0.6%; IAC: 32/231, 13.9%) were observed more frequently with increasing lung adenocarcinoma invasiveness (both P=0.000). CONCLUSIONS: The prevalence and patterns of air bronchograms on MDCT can predict the invasiveness of small lung adenocarcinomas.

Mosaic Attenuation: Etiology, Methods of Differentiation, and Pitfalls.

Mosaic attenuation is a commonly encountered pattern on computed tomography that is defined as heterogeneous areas of differing lung attenuation. This heterogeneous pattern of attenuation is the result of diverse causes that include diseases of the small airways, pulmonary vasculature, alveoli, and interstitium, alone or in combination. Small airways disease can be a primary disorder, such as respiratory bronchiolitis or constrictive bronchiolitis, or be part of parenchymal lung disease, such as hypersensitivity pneumonitis, or large airways disease, such as bronchiectasis and asthma. Vascular causes resulting in mosaic attenuation are typically chronic thromboembolic pulmonary hypertension, which is characterized by organizing thrombi in the elastic pulmonary arteries, or pulmonary arterial hypertension, a heterogeneous group of diseases affecting the distal pulmonary arterioles. Diffuse ground-glass opacity can result in a mosaic pattern related to a number of processes in acute (eg, infection, pulmonary edema), subacute (eg, organizing pneumonia), or chronic (eg, fibrotic diseases) settings. Imaging clues that can assist the radiologist in pinpointing a diagnosis include evidence of large airway involvement, cardiovascular abnormalities, septal thickening, signs of fibrosis, and demonstration of airtrapping at expiratory imaging.

Regulatory Considerations in the Design and Manufacturing of Implantable 3D-Printed Medical Devices.

Three-dimensional (3D) printing, or additive manufacturing, technology has rapidly penetrated the medical device industry over the past several years, and innovative groups have harnessed it to create devices with unique composition, structure, and customizability. These distinctive capabilities afforded by 3D printing have introduced new regulatory challenges. The customizability of 3D-printed devices introduces new complexities when drafting a design control model for FDA consideration of market approval. The customizability and unique build processes of 3D-printed medical devices pose unique challenges in meeting regulatory standards related to the manufacturing quality assurance. Consistent material powder properties and optimal printing parameters such as build orientation and laser power must be addressed and communicated to the FDA to ensure a quality build. Postprinting considerations unique to 3D-printed devices, such as cleaning, finishing and sterilization are also discussed. In this manuscript we illustrate how such regulatory hurdles can be navigated by discussing our experience with our group's 3D-printed bioresorbable implantable device.

Unusual bronchial foreign body.

We present an unusual case of bronchial foreign body in an adult who presented with bronchiectasis more than two decades later. The patient was unaware of his accidental aspiration of the foreign body, and the final diagnosis was made intraoperatively.

A hybrid method for airway segmentation and automated measurement of bronchial wall thickness on CT.

Inflammatory and infectious lung diseases commonly involve bronchial airway structures and morphology, and these abnormalities are often analyzed non-invasively through high resolution computed tomography (CT) scans. Assessing airway wall surfaces and the lumen are of great importance for diagnosing pulmonary diseases. However, obtaining high accuracy from a complete 3-D airway tree structure can be quite challenging. The airway tree structure has spiculated shapes with multiple branches and bifurcation points as opposed to solid single organ or tumor segmentation tasks in other applications, hence, it is complex for manual segmentation as compared with other tasks. For computerized methods, a fundamental challenge in airway tree segmentation is the highly variable intensity levels in the lumen area, which often causes a segmentation method to leak into adjacent lung parenchyma through blurred airway walls or soft boundaries. Moreover, outer wall definition can be difficult due to similar intensities of the airway walls and nearby structures such as vessels. In this paper, we propose a computational framework to accurately quantify airways through (i) a novel hybrid approach for precise segmentation of the lumen, and (ii) two novel methods (a spatially constrained Markov random walk method (pseudo 3-D) and a relative fuzzy connectedness method (3-D)) to estimate the airway wall thickness. We evaluate the performance of our proposed methods in comparison with mostly used algorithms using human chest CT images. Our results demonstrate that, on publicly available data sets and using standard evaluation criteria, the proposed airway segmentation method is accurate and efficient as compared with the state-of-the-art methods, and the airway wall estimation algorithms identified the inner and outer airway surfaces more accurately than the most widely applied methods, namely full width at half maximum and phase congruency.

Bronchus sign on thin-section computed tomography is a powerful predictive factor for successful transbronchial biopsy using endobronchial ultrasound with a guide sheath for small peripheral lung lesions: a retrospective observational study.

BACKGROUND: Recent advances in bronchoscopy, such as transbronchial biopsy (TBB) using endobronchial ultrasonography with a guide sheath (EBUS-GS), have improved the diagnostic yield of small-sized peripheral lung lesions. In some cases, however, it is difficult to obtain adequate biopsy samples for pathological diagnosis. Adequate prediction of the diagnostic accuracy of TBB with EBUS-GS is important before deciding whether bronchoscopy should be performed. METHODS: We retrospectively reviewed 149 consecutive patients who underwent TBB with EBUS-GS for small-sized peripheral lung lesions (≤30 mm in diameter) from April 2012 to March 2013. We conducted an exploratory analysis to identify clinical factors that can predict an accurate diagnosis by TBB with EBUS-GS. All patients underwent thin-section chest computed tomography (CT) scans (0.5-mm slices), and the CT bronchus sign was evaluated before bronchoscopy in a group discussion. The final diagnoses were pathologically or clinically confirmed in all studied patients (malignant lesions, 110 patients; benign lesions, 39 patients). RESULTS: The total diagnostic yield in this study was 72.5% (95% confidence interval: 64.8-79.0%). Lesion size, lesion visibility on chest X-ray, and classification of the CT bronchus sign were factors significantly associated with the definitive biopsy result in the univariate analysis. In the multivariate analysis, only the CT bronchus sign remained as a significant predictive factor for successful bronchoscopic diagnosis. The CT bronchus sign was also significantly associated with the EBUS findings of the lesions. CONCLUSION: Our results suggest that the CT bronchus sign is a powerful predictive factor for successful TBB with EBUS-GS.