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Updated: May 20, 2026

Time-Resolved, Dynamic Computed Tomography Angiography for Characterization of Aortic Endoleaks and Treatment Guidance via 2D-3D Fusion-Imaging
Published on: December 9, 2021
[Atoll sign: A CT finding with clinical impact]
Marie Verstraeten1,2, Dieter Stevens1
1Universitair Ziekenhuis Gent, afd. Longziekten, Gent, België.
Abstract:
A 48-year-old woman with metastatic cervical cancer treated with pembrolizumab and bevacizumab developed drug-induced organizing pneumonia characterized by the atoll sign on chest CT: rounded ground-glass opacities with a peripheral consolidation ring. Discontinuation of therapy led to complete radiological resolution and significant improvement in DLCO.
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Effects of EDTA on End-Point Detection Methods
In the visual method, metal-ion indicators (metallochromic dyes), which have distinct colors in their free and complex forms, are added to the mixture to signal the titration's end point. They form stable complexes with metal ions, but these complexes are weaker than the corresponding metal–EDTA complexes. As a result, EDTA...

