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The 'ring sign': is it a reliable indicator for cerebral spinal fluid?

D J Dula1, W Fales

  • 1Department of Emergency Medicine, Geisinger Medical Center, Danville, Pennsylvania.

Annals of Emergency Medicine
|April 1, 1993
PubMed
Summary

The ring sign reliably detects cerebrospinal fluid (CSF) when mixed with blood, forming a halo. However, this blood-fluid ring test is not exclusive to CSF, as other fluids also produce the sign.

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