33 results
The fourth pattern includes abnormalities that result in decreased lung attenuation or air-filled lesions.
These include:
- Emphysema
-
on the basis of HRCT ... #Diagnosis #Radiology ... #Pulmonary #CTChest ... Differential #Diagram #Comparison ... #SignetRing #RadiologyAssistant
Upper lung zone preference is seen in:
- Inhaled particles: pneumoconiosis (silica or coal)
- Smoking related diseases
(centrilobular emphysema ... bronchiolitis (RB-ILD ... edema #Diagnosis ... #Radiology #Pulmonary ... #HRCT #ChestCT
Low Attenuation pattern 
1. Lymphangiomyomatosis (LAM): uniform cysts in woman of child-bearing age; no history of
Centrilobular emphysema ... #Clinical #Radiology ... #HRCT #CTChest ... Cystic #Pattern #Comparison ... #Table #RadiologyAssistant
Low Attenuation pattern (2) 
1. Centrilobular emphysema: low attenuation areas without walls. Notice the centrilobular artery
Centrilobular emphysema ... #Clinical #Radiology ... #HRCT #CTChest ... Cystic #Pattern #Comparison ... #Table #RadiologyAssistant
Nodular pattern
1. Hypersensitivity pneumonitis: ill defined centrilobular nodules.
2. Miliary TB: random nodules
3. Sarcoidosis: nodules with perilymphatic
Hypersensitivity pneumonitis: ill ... #Clinical #Radiology ... #HRCT #CTChest ... Nodular #Pattern #Comparison ... #Table #RadiologyAssistant
Differential diagnosis of Langerhans cell histiocytosis.
Nodular LCH:
- Sarcoidosis: perilymphatic distribution.
- Metastases: random distribution.
Cystic LCH:
- LAM: round
Differential diagnosis ... Centrilobular emphysema ... #Radiology #CTChest ... #Differential #Comparison ... #Table #RadiologyAssistant
Basic Interpretation
A structured approach to interpretation of HRCT involves the following questions:
What is the dominant HR-pattern:
reticular
nodular
high
low attenuation (emphysema ... bronchiectasis) #Diagnosis ... #Radiology #Pulmonary ... #HRCT #CTChest ... #RadiologyAssistant
UIP with honeycombing (left) and chronic HP (right)
Differential diagnosis of Hypersensitivity Pneumonitis.
Subacute stage:
- RB-ILD: seen in
centrilobular emphysema ... show very similar HRCT ... #Radiology #CTChest ... #UIP #Comparison ... #RadiologyAssistant
Perilymphatic distribution
Perilymphatic nodules are most commonly seen in sarcoidosis.
They also occur in silicosis, coal-worker's pneumoconiosis and
in differential diagnosis ... #Diagnosis #Radiology ... #Pulmonary #HRCT ... #CTChest #Perilymphatic ... #Differential #RadiologyAssistant
On the left a typical case of panlobular emphysema.
There is uniform destruction of the underlying architecture
the other hand, mild ... difficult to detect on HRCT ... #Clinical #Radiology ... #CTChest #Panlobular ... #RadiologyAssistant