Aspergilloma, also known as mycetoma or fungus ball, is characterized by a round or oval mass with soft-tissue attenuation within a preexisting lung cavity. The typical computed tomography (CT) aspect of an aspergilloma is a mass separated from the wall of the cavity by an airspace of variable size and shape, resulting in the air crescent sign, also known as the meniscus sign. This CT feature is non-specific and can be simulated by several other entities that result in intracavitary masses. This review describes the main clinical and imaging aspects of the infectious and non-infectious diseases that may present with fungus-ball appearance, including pulmonary hydatid cyst, Rasmussen aneurysm, pulmonary gangrene, intracavitary clot, textiloma, lung cancer, metastasis, and teratoma, focusing on the differential diagnosis.
Air crescent sign Aspergillosis Fungus ball Computed tomography Pulmonary diseases
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The authors declare that they have no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
Knower MT, Kavanagh P, Chin R Jr (2002) Intracavitary hematoma simulating mycetoma formation. J Thorac Imaging 17:84–88CrossRefPubMedGoogle Scholar
Franquet T, Müller NL, Giménez A, Guembe P, de La Torre J, Bagué S (2001) Spectrum of pulmonary aspergillosis: histologic, clinical, and radiologic findings. Radiographics 21:825–837CrossRefPubMedGoogle Scholar
Gazzoni FF, Severo LC, Marchiori E, Guimarães MD, Garcia TS, Irion KL et al (2014) Pulmonary diseases with imaging findings mimicking aspergilloma. Lung 192:347–357CrossRefPubMedGoogle Scholar
Gazzoni FF, Hochhegger B, Severo LC, Marchiori E, Pasqualotto A, Sartori AP et al (2014) High-resolution computed tomographic findings of Aspergillus infection in lung transplant patients. Eur J Radiol 83:79–83CrossRefPubMedGoogle Scholar
Wang W, Gao L, Wang X (2013) Rasmussen’s aneurysm with aspergilloma in old, healed pulmonary tuberculosis. Clin Imaging 37:580–582CrossRefPubMedGoogle Scholar
Castañer E, Gallardo X, Rimola J, Pallardó Y, Mata JM, Perendreu J et al (2006) Congenital and acquired pulmonary artery anomalies in the adult: radiologic overview. Radiographics 26:349–371CrossRefPubMedGoogle Scholar
Park Y, Kim TS, Yi CA, Cho EY, Kim H, Choi YS (2007) Pulmonary cavitary mass containing a mural nodule: differential diagnosis between intracavitary aspergilloma and cavitating lung cancer on contrast-enhanced computed tomography. Clin Radiol 62:227–232CrossRefPubMedGoogle Scholar
Guimaraes MD, Hochhegger B, Santos MK, Santana PR, Júnior Sousa AS et al (2015) Magnetic resonance imaging of the chest in the evaluation of cancer patients: state of the art. Radiol Bras 2015(48):33–42CrossRefGoogle Scholar
Bandoh S, Fujita J, Fukunaga Y, Yokota K, Ueda Y, Okada H et al (1999) Cavitary lung cancer with an aspergilloma-like shadow. Lung Cancer 26:195–198CrossRefPubMedGoogle Scholar
Goto T, Kato R, Maeshima A, Oyamada Y (2010) Cavitary lung cancer with an aspergilloma-like shadow. J Thorac Oncol 5:580–581CrossRefPubMedGoogle Scholar
Seo JB, Im JG, Goo JM, Chung MJ, Kim MY (2001) Atypical pulmonary metastases: spectrum of radiologic findings. Radiographics 21:403–417CrossRefPubMedGoogle Scholar
Watanabe H, Uruma T, Tsunoda T, Tazaki G, Suga A, Nakamura Y et al (2014) Lung metastasis of transitional cell cancer of the urothelium, with fungus ball-like shadows closely resembling aspergilloma: a case report and review of the literature. Oncol Lett 8:95–98CrossRefPubMedPubMedCentralGoogle Scholar
Gaeta M, Volta S, Scribano E, Loria G, Vallone A, Pandolfo I (1996) Air-space pattern in lung metastasis from adenocarcinoma of the GI tract. J Comput Assist Tomogr 20:300–304CrossRefPubMedGoogle Scholar
Barreto MM, Valiante PM, Zanetti G, Boasquevisque CH, Marchiori E (2015) Intrapulmonary mature teratoma mimicking a fungus ball. Lung 193:443–445CrossRefPubMedGoogle Scholar
Giunchi F, Segura JJ (2012) Primary malignant teratoma of lung: report of a case and review of the literature. Int J Surg Pathol 20:523–527CrossRefPubMedGoogle Scholar
Makarawo TP, Finnikin S, Woolley S, Bishay E (2009) Trichoptysis: a hairy presentation of a rare tumour. Interact Cardiovasc Thorac Surg 9:733–735CrossRefPubMedGoogle Scholar
Roig J, Aguilar X, Maestre J, Domingo C, Morera J (1991) Pulmonary mass and air meniscus sign in a 19-year-old man. Chest 100:562–563CrossRefPubMedGoogle Scholar