Ground glass opacification on CT

Associate Editor-In-Chief:

Overview
Ground glass opacification (GGO) is seen as increased opacification of lung without obscuration of the bronchial and vascular markings. Ground glass opacification can represent partially filled alveoli, active inflammation, or fine fibrosis below the resolution of CT images.

Differential Diagnosis

 * Alveolar proteinosis
 * Acute chest syndrome
 * Acute lung transplant rejection
 * Adult respiratory distress syndrome (ARDS)
 * Acute interstitial pneumonitis
 * Bleeding: Pulmonary hemorrhage. Etiologies of pulmonary hemorrhage include:
 * Goodpasture's syndrome
 * Wegener's granulomatosis
 * Systemic Lupus Erythematosus
 * Vasculitis
 * Anticoagulation
 * Blunt or penetrating trauma


 * Bronchiolitis obliterans oganizing pneumonia (BOOP)
 * Bronchiolitis-associated interstitial lung disease
 * Bronchoalveolar lavage
 * CMV (Herpes simplex and pneumocystits)
 * Contusion
 * Cancer (Bronchoalveolar cell carcinoma)
 * Drug toxicity
 * Desquamative interstitial pneumonitis
 * Extrinsic allergic alveolitis
 * Eosinophilic pneumonia
 * Edema
 * Fibrosis
 * Granulomatous disease (Sarcoidosis)
 * Infection (Pneumocystis carinii pneumonia)