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I saw the "atoll sign" - and now I need a tropical vacation
James M Williams1, Philip Hurst2, Prabhakar Shantha Rajiah1
1Department of Radiology, Mayo Clinic, Rochester, MN, USA.
Abstract:
The atoll sign describes ring-shaped opacities surrounding central ground glass attenuation seen on chest CT and was first associated with organizing pneumonia. The name is derived from the Maldives' language, denoting a ring or crescentic-shaped coral reef island surrounding a central lagoon. Although biopsy is usually required for diagnosis, understanding some of the more common pathologies associated with the atoll sign may help narrow a differential and guide management.
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