The sentinel clot sign is a useful CT finding for the evaluation of probable anatomic sites of hemorrhage.
On CT, acute clotted hemorrhage typically has high attenuation (45 to 80 HU), whereas surrounding areas of acute non-clotted hemorrhage or more chronic hemorrhage have either lower attenuation (25 to 45 HU) or fluid attenuation (0 to 20 HU).
This is the basis for the sentinel clot sign, areas of higher attenuation are likely to represent more acute clotted hemorrhage, and are therefore more likely to indicate the anatomic sites of hemorrhage.
- 1. Orwig D, Federle MP. Localized clotted blood as evidence of visceral trauma on CT: the sentinel clot sign. AJR Am J Roentgenol. 1989;153 (4): 747-9. doi:10.2214/ajr.153.4.747 - Pubmed citation
- 2. Dähnert WF. Radiology Review Manual. Lippincott Williams & Wilkins. (2011) ISBN:1609139437. Read it at Google Books - Find it at Amazon
- 3. Haaga JR, Boll D. CT and MRI of the whole body. Mosby. (2009) ISBN:0323053750. Read it at Google Books - Find it at Amazon