Learning objectives
The aims of this poster are to make the audience:
Learn to avoid pitfalls when analyzing ground-glass opacities (GGO) on a chest CT scan
Learn distinctive signs that can lead us to the etiology of GGO
Background
GGO are defined by the glossary of the Fleishner society as “hazy increased opacity of lung,
with preservation of bronchial and vascular margins.» (1) It’s a usual finding which has diverse etiologies.
In our daily practice,
many radiologists find difficulties to deal with them and identify semiologic characteristics that may lead to the right diagnosis.
Findings and procedure details
1. How to diagnose Ground Glass opacities?
Focal GGO appear as “hazy increased opacity of lung,
with preservation of bronchial and vascular margins.»(1) (Fig.1).
Diffuse GGO are sometimes more difficult to identify because of the lack of normal parenchyma: In this case,
comparing parenchyma’s density,
to air density in the bronchiole can help us make the diagnosis.
(Fig.
2).
Pay attention to pitfalls!!!
Mind expiratory acquisitions which may lead to wrong diagnosis of GGO (2): It’s important to always check the shape of the trachea....
Conclusion
Etiologies of GGO are diverse but a thorough analysis of patient’s history and CT scan semiology can lead radiologists to the adequate diagnosis.
References
(1): Hansell D,
Bankier A,
MacMahon H,
McLoud T,
Müller N,
Remy J.
Fleischner Society: Glossary of terms for thoracic imaging.
Radiol.
2008;246(3):697-722
(2): Khalil A,
Baunin C,
Beigelman C,
Brauner M,
Carette MF,
Debray MP and al .
Imagerie thoracique de l’adulte et de l’enfant.
2ème edition.
Paris: Elsevier Masson; 2013.
(3): El-Sherief A,
Gilman M,
Healey T,
Tambouret R.,
Shepard JA,
Abbott G.
and al.
Clear Vision Through the Haze: A Practical Approach to Ground-Glass Opacity.
Curr Probl Diagn.
2014:140-58
(4) MacMahon H,...