000 Emphysema Centrilobular

Centrilobular is a term to describe changes that are centered
around the central portion of the secondary pulmonary lobules. It is
commonly associated with diseases that affect the bronchioles and
surrounding lung parenchyma, such as centrilobular emphysema,
respiratory bronchiolitis, and hypersensitivity pneumonitis.
Centrilobular changes are diagnosed through imaging, particularly
high-resolution CT scans, where small nodules or areas of reduced
lung density are observed in a centrilobular distribution

  • Buzz Words
    • Alveolar destruction
    • Loss of elasticity
    • starting in the respiratory bronchiole and progressing toward the proximal and central portion of the secondary lobule

Normal (above)  And Centrilobular Emphysema Starting at the Respiratory Bronchiole

Normal Acinus and Acinus in Emphysema
Image on the left shows normal size and appearance of terminal bronchioles and alveoli. On the right the image shows the effects on the respiratory bronchioles and when severe, on the alveoli as well
Ashley Davidoff MD TheCommonVein.net

Definition

  • Emphysema is an inflammatory disease of the lung
    • characterized
      • alveolar and small vessels destruction with
      • Loss of elasticity
      • starting in the respiratory bronchiole and progressing toward the proximal and central portion of the secondary lobule
    • clinically characterised by
      • shortness of breath, and other respiratory problems.
  • Caused by
    • smoking
  • Results
    • Structurally
      • alveolar wall destruction
        • progressive expansion of the acinus without fibrosis,
      • decreased lung elasticity,
      • architectural  distortion of the capillary bed.\ loss of functioning surface are
    • Clinically
      • presents in middle age and older,
      • as a barrel chested
      • “pink-puffer,
      • breathing often with pursed lips, with
      • insidious and unrelenting dyspnea.
    • Diagnosis
      •  CXR shows
        • hyperinflated lungs, with
        • propensity for the upper lobes,
        • flattened diaphragms and a
        • s carinatum)”barrel chest”
      • CT
        • Swiss Cheese appearance
          • areas of low attenuation correspond to the regions where the alveoli and bronchioles are enlarged due to destruction
          • resemble the appearance of holes or gaps, similar to the holes in Swiss cheese.
      • Lug Function tests
        • reduction in the maximal expiratory flow during forced exhalation. (decreased FEV1)
      • Treatment
        • bronchodilators,
        • diuretics,
        • corticosteroids,
        • antibiotics
        • low-flow oxygen,
        • pulmonary rehabilitation.

Centrilobular Emphysema Dilated Air Spaces Localized around a Bronchovascular Bundle.

Centrilobular Emphysema
This drawing shows a secondary lobule with centrally located dilated airspaces starting with the respiratory bronchiole and extending to the proximal structures including the alveolar ducts, sacs and alveoli
Ashley Davidoff TheCommonVein.net

Alveolar Wall Destruction Localized around a Bronchovascular Bundle.

Histology of Centrilobular Emphysema,
Alveolar wall destruction is localized around a bronchovascular bundle.
Courtesy Yale Rosen MD
Micrograph showing emphysema (left – large empty spaces) and lung tissue with relative preservation of the alveoli (right)
Low magnification micrograph of emphysema. H&E stain. The left of image shows severe emphysema (large empty spaces). The lung tissue on the right of the image has relative preservation of the alveoli. The top of the image is very near the pleural surface.
Courtesy Nephron
Emphysema_Lung_10x
Micrograph of empysema lung showing dialated, large alveoli separated by thin septa. Some septae are ruptured and appear to be floating in the alveloar spaces. Grossly emphysematous lung appears pale and voluminous.
Source DEPARTMENT OF PATHOLOGY, CALICUT MEDICAL COLLEGE

 

Gross Anatomy of Upper Lobe and Apical Centrilobular Emphysematous Changes and Normal Lung Below

Gross Anatomy of Upper Lobe and Apical Centrilobular Emphysematous Changes
Ashley Davidoff MD

Normal Secondary Lobule

Secondary Lobule
The top image (a) shows an anatomic drawing of a secondary lobule of the lung subtended by a lobular bronchiole (lb) and arteriole (pa). The interlobular septum contains the venule (red) lymphatic (yellow) and septum (maroon)
The anatomical specimen of the lung (b) shows normal intralobular parenchyma while image c shows the centrilobular arteriole (navy blue) and centrilobular bronchiole (teal) and interlobular venule (red) and lymphatics (yellow) The interlobular septum is slightly thickened
Ashley Davidoff TheCommonVein.net

Normal CT

Normal CT of the Upper Lung Fields on Lung Windows
Ashley Davidoff TheCommonVein.net

Centrilobular Emphysema Gross Pathology 

Emphysema
This is an image of an emphysematous lung. Note the larger air spaces where the septae between the alveoli, alveolar sac alveolar ducts and respiratory bronchioles have been broken down (green).
The bronchovascular bundle consisting of the arteriole (navy blue) and bronchiole (teal) subtends the secondary lobule. The pulmonary venule (red) originates from interlobular septa where it is intimately related to the lymphatics. 19932e
Apical Emphysematous Changes
Ashley Davidoff MD 19.jpg

Electron Microscopy

SEM lung with emphysema
David Gregory & Debbie Marshall
Licence: Attribution 4.0 International (CC BY 4.0)

 

CXR Emphysema

Diaphragm in Emphysema
Flattened and Partially Inverted
Ashley Davidoff MD TheCommonvein.net
Diaphragm in Emphysema
Flattened and Partially Inverted
Ashley Davidoff MD TheCommonvein.net
The lateral examination of the chest shows the classical barrel shape to the chest with an increase in the retrosternal air space and flattening of the
#signs in medicine
Ashley Davidoff MD TheCommonVein.net

CT Scan of Centrilobular Emphysema Swiss Cheese

CT Scan of Centrilobular Emphysema
The axial CT of a 66 year old female with moderately severe centrilobular emphysema of the upper lobes. The magnified views show the focal central punctate density of the pulmonary artery indicating the presence of the central bronchovascular bundle (red arrow)
Ashley Davidoff MD The Common Vein.net

Side by Side Normal and Centrilobular Emphysema

Normal and Emphysema
The imaging difference between healthy  lungs (thumbs up) and emphysematous lungs (thumbs down)
Ashley Davidoff MD TheCommonVeein.net  lungs-0071
key words emphysema, CTscan cigarettes smoking

Pathophysiology of Cigarette Smoking on Medium Sized Airways, Small Airways and Alveoli

Pathophysiology of Cigarette Smoking on Medium Sized Airways, Small Airways and Alveoli
Ashley Davidoff  TheCommonVein.net lungs-00683

Structural Effects of Smoking on the Respiratory Bronchiole , Alveolar Ducts and Alveolar Sacs

Structural Effects of Smoking on the 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, vessel destruction 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
Smoking and the Alveolus –
The effect of the proteases and and elastases cause destruction of the alveoli and loss of elasticity, and therefore overall function. The destruction leads to bullous disease
The accumulation of smokers macrophage, and in the case of Langerhans cell histiocytosis leads to space occupation of the alveoli also reducing function
Ashley Davidoff TheCommonVein.net lungs-00687

 

It Starts at the Respiratory Bronchiole

Normal Acinus and Emphysema
Image on the left shows normal size and appearance of terminal bronchioles and alveoli. On the right the image shows the effects on the respiratory bronchioles and when severe, on the alveoli as well
Ashley Davidoff MD
TheCommonVein.net
CT scan of Normal Lungs and Lungs with Centrilobular Emphysema Caused by Cigarette Smoking
Ashley Davidoff Art TheCommonVein.net
Axial view of the upper lobes of a 66year female with centrilobular emphysema shows an expanded lobule with a centrilobular vessel in the middle characteristic of centrilobular emphysema
Ashley Davidoff MD TheCommonvein.net

 

Magnified view of the upper lobes of a 66year female with centrilobular emphysema shows an expanded lobule with a centrilobular vessel in the middle characteristic of centrilobular emphysema
Ashley Davidoff MD TheCommonvein.net

 

Emphysema

  • Centrilobular emphysema  is an
    • obstructive lung disease
    • caused by
      • obstructive bronchiolitis  affecting the
        •  region of the proximal respiratory bronchiole
        • allowing  air  into the secondary lobule but inhibiting
        • exhalation with resultant
        • air trapping and destruction  of lung tissue
    • Destruction of small airways can lead to the formation of large bullae
EMPHYSEMA
Micrograph showing emphysema (left – large empty spaces) and lung tissue with relative preservation of the alveoli (right)
Courtesy Nephron
MORGAGNI
Giovanni Battista Morgagni, who made one of the earliest recorded descriptions of emphysema in 1769
Public Domain

 

References and Links