It should not be confused with the air crescent sign which is seen in recovering angioinvasive aspergillosis 4. The air crescent sign heralds improvement in the condition.
In practice, it is likely that the term Monod sign will receive blank stares. The air around the mycetoma is often crescent-shaped and hence, the term air crescent sign is used interchangeably by many to refer to both pathological processes.
History and etymology
The sign was first described by G D Pesle and Olivier Monod in 1954 6.
- 1. Roig J, Aguilar X, Maestre J, Domingo C, Morera J. Pulmonary mass and air meniscus sign in a 19-year-old man. Chest. 1991; 100(2): 562-3. doi:10.1378/chest.100.2.562 [pubmed citation]
- 2. Takahashi N, Kawashima A, Stroehlein KB, Oldham SA. Mycetoma of the lung in a cavity that developed from a gunshot wound. AJR Am J Roentgenol. 1999; 172(2): 369-71. AJR Am J Roentgenol [pubmed citation]
- 3. Thompson BH, Stanford W, Galvin JR, Kurihara Y. Varied radiologic appearances of pulmonary aspergillosis. Radiographics. 1995; 15(6): 1273-84. Radiographics [pubmed citation]
- 4. Imaging of pulmonary infections. editors, Nestor L. MÃ¼ller, TomÃ¡s Franquet, Kyung Soo Lee; associate editor, C. Isabela S. Silva. Philadelphia : Lippincott Williams & Wilkins, c2007. ISBN: 078177232X
- 5. Abramson S. The air crescent sign. Radiology. 2001;218 (1): 230-2. doi:10.1148/radiology.218.1.r01ja19230 - Pubmed citation
- 6. PESLE G, O MONOD. CHEST Journal. 1954;25 (2): . doi:10.1378/chest.25.2.172