Imaging of small airways diseases

Area of Science:

• Radiology
• Pulmonary Medicine
• Diagnostic Imaging

Background:

• Idiopathic (BOOP) and secondary proliferative bronchiolitis present similar radiographic findings.
• Patchy, peripheral airspace disease is a common radiographic characteristic of both BOOP forms.
• Chest radiography for constrictive bronchiolitis is often nonspecific.

Purpose of the Study:

• To outline the radiographic and CT findings in various forms of bronchiolitis.
• To highlight the diagnostic utility of CT in constrictive bronchiolitis.
• To differentiate respiratory bronchiolitis from idiopathic pulmonary fibrosis (IPF) using imaging.

Main Methods:

• Review of radiographic and CT imaging features of bronchiolitis.
• Correlation of imaging findings with specific bronchiolitis subtypes.
• Comparison of imaging characteristics between different interstitial lung diseases.

Main Results:

• Patchy airspace disease, often peripheral, is seen in idiopathic (BOOP) and secondary proliferative bronchiolitis.
• CT may reveal patchy, lobular hyperlucency, with or without bronchiectasis, in constrictive bronchiolitis.
• HRCT can suggest respiratory bronchiolitis through hazy lung density or centrilobular nodules, distinguishing it from IPF.

Conclusions:

• Radiographic presentation of BOOP can have prognostic implications.
• CT imaging plays a crucial role in diagnosing constrictive bronchiolitis.
• HRCT aids in differentiating respiratory bronchiolitis from IPF based on specific lung density patterns.