The main purpose of this work is to compare the diagnostic accuracy (DA) of chest X ray (CXR), chest computerized tomography (CT)and lung grey scale ultrasonography (US)in evaluation of lung abscess and determine the role of color doppler ultrasound in diagnosis of lung abscess.

Sixteen patients with suspected lung abscess were evaluated by CXR, chest CT, grey scale and colour doppler chest sonography. Chest CT revealed the highest DA (98.5%) with 100% sensitivity, 98.3% specificity, 88.9% PPV and 100% NPV. The specificity, sensitivity, PPV, NPV and DA of chest X ray were 98.3%, 75%, 85.7%, 96.6% and 95.5% respectively. Grey scale US had the least sensitivity (53.3%), specificity was 98.2%, PPV 96.7%, NPV 67.7% and DA 93.1%. CDS showed absent vascularity were observed in 9 lesions (60%), scanty and marked vascularity were equally detected each in 3 lesions (20%) with 66.7% showing THI flow and 33.3% showing MHI flow. The present study revealed that chest CT is considered the most accurate radiological procedure for diagnosis of lung abscess. Although its low sensitivity, grey scale US has a relatively high specificity in diagnosing lung abscess.

Keywords: Lunggrey scale ultrasonography, Lung abscess, Chest X ray, Computed tomography, Color Doppler sonography.

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Bahaa Ibrahim Mohamed

Department of Chest, Minia University, Egypt