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What is Gas shadow in hea and vessels are seen in and explain in detail?
Robe sign - the presence of a gas shadow within the hea or the greater vessels, seen in cases of fetal death in utero.It is a rare sign caused by postmoem blood degeneration, usually seen 1-2 days after death; and may be seen as early as 12 hours(Ref: Diagnostic Ultrasound by Carol M. Rumack, Stephanie R. Wilson, J. William Charboneau, and Deborah Levine,4thed, page 1090)