China
Africa
Explore chapters and articles related to this topic
Lung Consilidation, Ground Glass Shadowing, Obstructive Emphysema, Collateral Air-draft, Mucocoeles, patterns of Collapse, Lung Torsion and Herniation.
Published in Fred W Wright, Radiology of the Chest and Related Conditions, 2022
Kohn (1893) described the inter-alveolar pores ('Poren'), but noted that communicating 'holes' had been seen by Luschka in 1863. They were further studied by Loosli (1933), Macklin (1935), Culiner and Reich (1961), Reich and Abouav (1965) and Cordingly (1972). As Culiner and Reich pointed out: "in contra-distinction to the segments of the lobe, the total lobe is an isolated unit with essentially no collateral channel communications with adjacent lobes. Thus, total lobar bronchial obstruction is invariably followed by collapse of the lobe and absence of aeration", whereas "segmental bronchial occlusion may be followed by ventilation of that segment of lung tissue through collateral channels." Since the 'pores of Kohn' are, like bronchi, larger in inspiration and smaller on expiration, there is a partial check valve mechanism in these pathways, and some obstructive emphysema may be present in the lung inflated by collateral air drift. However, the resistance through collateral channels appears to decrease with developing emphysema (Hogg et al., 1969), and may be a mechanism causing partial compensation (Terry et al., 1978).
The Tight-Skin (Tsk) Mutation, Chromosome 2
Published in John P. Sundberg, Handbook of Mouse Mutations with Skin and Hair Abnormalities, 2020
Lungs from Tsk/+ mice had enlargement of alveoli, the presence of focal aggregates of macrophages, lymphocytes, and neutrophils, both within the alveoli and interstitium, thinning of alveolar walls, and formation of bullae and subpleural cysts. Severity varied between individuals. By scanning electron microscopy, lungs had generalized air-space enlargement of bullae and a marked increase in the number and size of the pores of Kohn.9,10 Quantitation of neutrophils by bronchoalveolar lavage demonstrated a significant increase over controls associated with normal proportions of T- and B-lymphocytes. There was no evidence of infection in the lungs.9,11
The Type II Pneumocyte
Published in Jacques R. Bourbon, Pulmonary Surfactant: Biochemical, Functional, Regulatory, and Clinical Concepts, 2019
Type II cells are found alone, among type I pneumocytes, or aggregated in small groups in niches of the alveolar surface, especially in regions where the walls of several adjacent alveoli meet.30 In the adult lung, they are sometimes associated with interalveolar openings (pores of Kohn).10,31,32 Whether they participate in the genesis of these structures is not known.
Device profile of the Zephyr endobronchial valve in heterogenous emphysema: overview of its safety and efficacy
Published in Expert Review of Medical Devices, 2021
Steven R. Verga, Gerard J. Criner
Target lobe selection was based on 50% destruction score [which is based on percentage of voxels < −910 Hounsfield units (HU) on (high resolution computed tomography (HRCT)] along with heterogenous emphysema defined by difference of 15% ≥ destruction score between the targeted and INL (calculated by Myrian quantitative software) [3,15]. ‘Complete’ fissure integrity (based on high HRCT visual score of ≥ 90% fissure completeness) was essential based on post-hoc analysis of VENT trial to identify potential patients that would benefit from BLVR [9]. Fissure integrity was a marker of collateral ventilation (CV), which would result in incomplete bronchial occlusion of target lobe due to alternative pathways of ventilation via pores of Kohn, bronchioloalveolar communications of Lambert and intrabronchiolar pathways of Martin [22]. With only 1 fissure, the left targeted lobe more likely to have no collateral ventilation [14,15,21,23]. Lobar perfusion aided in targeted lobe selection, for upper lobes <8% of total perfusion compared to lower lobe targets with <13% total perfusion [24].