lungs

Normal

Overview of the Anatomy of the Lungs
Ashley Davidoff MD TheCommonVein.net
lungs-0739
Overview of the Anatomy of the Lungs with a Focus on the Bronchioles 
Ashley Davidoff MD TheCommonVein.net lungs-0740nL01bronchioloes
Overview of the Anatomy of the Lungs Large Airways and Small Airways
Ashley Davidoff MD TheCommonVein.net lungs-0740nL
Small Airways
 Ashley Davidoff MD TheCommonVein.net lungs-0744
Small Airways
 Ashley Davidoff MD TheCommonVein.net lungs-0749
Histology of the terminal bronchiole 
Ashley Davidoff MD TheCommonVein.net lungs-0746
Histology of the respiratory bronchiole
Ashley Davidoff MD TheCommonVein.net lungs-0747
The Acinus, The Duct, and the Artery

Ashley Davidoff MD TheCommonVein.net lungs-0034

Artistic 3D Rendering Anatomy of the Distal Airways.
The lobular (most distal of the subsegmental airways give rise to the terminal bronchiole which give rise to the membranous airways. These include in order, the respiratory bronchiole, alveolar ducts and alveolar sacs
Ashley Davidoff TheCommonvein.net lungs-0007
Histology of the Large and Medium Sized Airways
Airways are lined by a pseudostratified ciliated columnar epithelium interspersed with mucus secreting goblet cells
Ashley Davidoff
TheCommonVein.net lungs-00674b01-lo res
As the medium sized airways progress to to the small airways they lose many of the goblet cells, become a simple epithelium and remain ciliated
Ashley Davidoff
TheCommonVein.net
lungs-00675-lo-res
As the terminal bronchial transitions to the respiratory bronchial the mucosa becomes non ciliated and cuboidal
Ashley Davidoff
TheCommonVein.net lungs-00676
Small Airways
The diagram shows the small airways of the lung  ie airways less than 2mm in size including the terminal bronchiole (tb), respiratory bronchiole (rb), alveolar ducts (ad) and alveolar sacs (as)  The terminal bronchiole is relatively thick walled  and it is  last duct of the conducting system of the airways. The respiratory bronchiole (rb) enters the secondary lobule and is the first duct to have gas exchange capability. There can be 3 orders of rb’s, and they branch into alveolar ducts, which branch in turn to alveolar sacs until they reach the alveoli, which is the final destination.
Ashley Davidoff MD TheCommonVein.net  lungs-0032-low res
The Acinus,
The Duct, and the Artery
The pulmonary arteriole accompanies the airway as it carries oxygen from the trachea to the alveoli. They part ways at the alveoli where the pulmonary venule then takes the oxygenated blood from capillary network around the alveoli back to the left atrium.
The intimate relationship of the airways and the pulmonary artery and their close approximation in size, is helpful in radiology, firstly to identify theese structures and secondly to define disease such as heart failure and bronchiectasis.
The acinus as shown in this image is defined as a unit of lung consisting of a single first order respiratory bronchiole that subtending a cluster of alveoli reminiscent of a bunch of grapes or berries (acinus in Latin means berry) .  The lobular bronchiole (lb) branches into the terminal bronchiole (tb), which then branches into the first order respiratory bronchiole (rb).  Subsequent branching  after the respiratory bronchiole,  includes in order, the  alveolar duct (ad), alveolar sac (as), and then finally the berry like alveoli.
Courtesy Ashley Davidoff 2019
lungs-0033-low res
The Acinus
The acinus is defined as a unit of lung consisting of a single first order respiratory bronchiole that subtending a cluster of alveoli reminiscent of a bunch of grapes or berries (acinus in Latin means berry) .  The lobular bronchiole (lb) branches into the terminal bronchiole (tb), which then branches into the first order respiratory bronchiole (rb).  Subsequent branching  after the respiratory bronchiole,  includes in order, the  alveolar duct (ad), alveolar sac (as), and then finally the berry like alveoli.
Courtesy Ashley Davidoff 2019
lungs-0030-low res
The diagram shows the structure of the airways and alveoli at the level of the secondary lobule. The terminal bronchiole (tb- pink) enters the secondary lobule and terminates in the respiratory bronchiole (rb purple) which lies in the center of the the secondary lobule (centrilobular). It gives rise to alveolar duct (ad yellow)which gives rise to the alveolar sac (as, teal blue. Finally the as terminates in the alveoli (a white)
Courtesy Ashley Davidoff MD
lungs-0028-low res
Artistic 3D Rendering Anatomy of the Distal Airways.
The lobular (most distal of the subsegmental airways give rise to the terminal bronchiole which give rise to the membranous airways. These include in order, the respiratory bronchiole, alveolar ducts and alveolar sacs
Ashley Davidoff TheCommonvein.net lungs-0007
Artistic 3D Rendering Anatomy of the Distal Airways.
The lobular (most distal of the subsegmental airways give rise to the terminal bronchiole which give rise to the membranous airways. These include in order, the respiratory bronchiole, alveolar ducts and alveolar sacs
Ashley Davidoff TheCommonvein.net lungs-0004
The Acinus with a lobular bronchiole, terminal bronchioles, respiratory bronchioles and alveoli. (alveolar duct and alveolar sacs are not shown)
Ashley Davidoff The CommonVein.net lungs-0002
A normal bronchiole 
Ashley Davidoff MD TheCommonVein.net lungs-0721

Diseases

Chronic Inflammation ? The Basics
I the early phases collagen starts to get laid down resulting in a thick walled bronchiole surrounded by a subacute inflammatory response of cells and resolving fluid. As the fibrotic process advances it gets denser resulting in traction bronchiectasis and bronchiolectasis. The ongoing may eventually constrict the airway and subsequently occlude occlude the airway
Ashley Davidoff MD TheCommonVein.net lungs-0700d
Membranous airways (respiratory bronchiole, alveolar ducts, alveolar sacs)
At the level of the membranous airways the effect is predominantly related to the loss of elasticity, and aberrant accumulation of smoking related macrophages.
The weakening and destruction results in emphysema and the abnormal accumulation of smoking related macrophages relates to DIP
Ashley Davidoff
TheCommonVein.net lungs-00685
Pathophysiology of Cigarette Smoking on Medium Sized Airways
Ashley Davidoff TheCommonVein.net lungs-00684
Pathophysiology of Cigarette Smoking on Medium Sized Airways, Small Airways and Alveoli
Ashley Davidoff
TheCommonVein.net lungs-00683

Amyloid

Amyloid in the Bronchiole
Ashley Davidoff TheCommonVein.net
Amyloid in the Arteriole
Ashley Davidoff TheCommonVein.net
Chronic Inflammation ?
Ashley Davidoff MD TheCommonVein.net lungs-0700d
The wall of the bronchiole breaks down and the cellular infiltrate may undergo necrosis resulting in thick -walled cavities, sometimes round in shape.
Ashley Davidoff MD TheCommonVein.net lungs-0725
The inflammatory response is often aggressive and may infiltrate the surrounding interstitium resulting in a spiculated appearance
Ashley Davidoff MD TheCommonVein.net lungs-0724
As the inflammatory response progresses it has mass effect on the and may eventually occlude the bronchiole becoming a nodule.
Ashley Davidoff MD TheCommonVein.net lungs-0724b
The inflammatory response is often aggressive and may infiltrate the surrounding interstitium resulting in a spiculated appearance. As the inflammatory response progresses it has mass effect on the bronchiole causing the bronchiole to become narrowed.
Ashley Davidoff MD TheCommonVein.net lungs-0723b
As the inflammatory response progresses it has mass effect on the bronchiole causing the bronchiole to become narrowed.
Ashley Davidoff MD TheCommonVein.net lungs-0723
Inflammatory response in the small airways attracts cellular interstitial infiltrates which surround the bronchiole. The diagram shows a bronchiole surrounded by an acute cellular inflammatory response
Ashley Davidoff MD TheCommonVein.net lungs-0722

Granulomatous Disease

Granuloma occludes the lumen of the centrilobular bronchiole and the peri-bronchiole inflammation has receded in this subacute to chronic phase
Ashley Davidoff MD TheCommonVein.net lungs-0731
Granuloma Impinges on the lumen of the centrilobular bronchiole The peri- bronchiole inflammation has receded in this subacute to chronic phase
Ashley Davidoff MD TheCommonVein.net lungs-0729
As the inflammatory response subsides, thin-walled cavities evolve, sometimes bizarre in shape.
Ashley Davidoff MD TheCommonVein.net lungs-0728b
As the inflammatory response subsides, thin-walled cavities evolve.
Ashley Davidoff MD TheCommonVein.net lungs-0728b -hi res
The wall of the bronchiole breaks down and the cellular infiltrate may undergo necrosis resulting in thick -walled cavities, sometimes bizarre in shape.
Ashley Davidoff MD TheCommonVein.net lungs-0726

Small Airway Fibrosis and Luminal Narrowing or Obstruction 
Ashley Davidoff MD TheCommonVein.net lungs-0778

 

Small Airway Fibrosis
Ashley Davidoff MD TheCommonVein.net lungs-0777

Eosinophilic Pneumonia

Advancing Acute Eosinophilic Pneumonia
Ashley Davidoff MD The CommonVein.net  lungs-0763
Eosinophilic Pneumonia
Ashley Davidoff MD The CommonVein.net lungs-0760b
Eosinophilic Pneumonia 
Ashley Davidoff TheCommonVein.net lungs-0757b
Eosinophilic Pneumonia
Ashley Davidoff TheCommonVein.net lungs-0757
Eosinophilic Pneumonia
Ashley Davidoff TheCommonVein.net lungs-0755
Pneumonia
The collage provides a perspective of purulent accumulation in the small airways and the alveoli that results in consolidation. A process that increases the density of the lungs to a net “white” regional density will result in a consolidation and in this case when the fluid is infected it is labelled “pneumonia” The net result on CT is air bronchograms within the non aerated dense lung tissue.
Ashley Davidoff MD TheCommonVein.net lungs-0734
Diseases of the small airways and the alveoli 
Ashley Davidoff MD TheCommonVein.net lungs-0733