Air crescent sign

What is ‘Air crescent sign’?

Air crescent sign appears as a crescent of air surrounding a soft-tissue mass in a pulmonary cavity and can be seen in both plain X-ray and CT scan.

Characteristic of invasive Pulmonary Aspergillosis,

also be seen in

1. cavitating neoplasms,
2. lung abscesses,
3. infections.

Mass in cavity separated from the wall of the cavity by a crescent-shaped airspace; it is known as an ‘air crescent sign.

In aspergilloma, this mass usually moves within the cavity when the patient changes the position and the sign is called a ‘Monod sign’

Air crescent sign

Mass in cavity separated from the wall of the cavity by a crescent-shaped airspace

Differences Between the Air Crescent Sign and the Monod Sign

‘Monod Sign’

In aspergilloma, this mass usually moves within the cavity when the patient changes the position and the sign is called a ‘Monod sign’

Most common presentation in aspergilloma

Haemoptysis secondary to reactive vascular granulation tissue is the most common presentation.

1. For brisk haemoptysis, an angiography and a selective bronchial artery embolisation.
2. Gold standard for treatment – surgical excision remains the gold standard in cases of recurrent haemoptysis,