Interstitial |
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Fig. 4.38 Portable CXR done in ICU demonstrating diffuse patchy airspace opacities. Additionally there are the following tubes/lines: ET tube in trachea above carina, feeding tube in stomach, two left chest tubes, PICC line at junction of left brachycephalic and SVC
Fig. 4.39 CT of same patient demonstrating “crazy paving” in RML and RLL (thin arrows on patient’s right) and bronchiectasis within consolidated LLL (wide arrow on patient’s left)
Cells (Malignancy)
Bronchoalveolar cell carcinoma (BAC), Kaposi’s sarcoma, and lymphoma can display as a consolidative pseudo-mass.
Figure 4.40 demonstrate perihilar consolidations in a child with Kaposi’s sarcoma.
Interstitial
Chest X-Rays showing interstitial markings include a large variety of abnormal processes including edema, inflammation, disease, and environmental exposure.
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Fig. 4.40 (a) PA and (b) lateral CXR demonstrating irregular perihilar patchy consolidations partially obliterating vasculature and right heart border in this patient with Kaposi’s sarcoma
a
b
4 Abnormal Lung Patterns
Interstitial |
65 |
Fig. 4.41 End-stage “Honeycomb” lung (Image courtesy of Ed Uthman, M.D.)
Interstitial markings appear on CXR and CT due to changes affecting the interstitium of the lung.
The composition of the pulmonary interstitium includes the:
•Alveolar walls, septi, and the connective tissue surrounding bronchi and vessels (peribronchial and perivascular spaces).
Mechanisms of infiltration include:
•Thickening of lung interstices
•Architectural destruction of interstitium (honeycomb or “end-stage” lung)
Interstitial pattern includes lines, dots, and/or holes (any combination of the three) as opposed to the fluffy opacities seen with consolidation. Keep in mind there can be mixed patterns with consolidation, airway, mass, or vascular. On CT, ground glass is another finding in interstitial pattern.
An example of a disease that would produce an interstitial pattern, in this case, lines and holes (honeycomb pattern). Figure 4.41 is a gross specimen lung from a patient who had end-stage lung disease.