Petechial Haemorrhages
Definition
Pin-point haemorrhages on the conjunctivae, eyelids, face and behind the ears, caused by venous congestion above the level of obstruction. Prominent in strangulation and incomplete hanging; sparse or absent in complete hanging.
- Common sites
- Conjunctivae, eyelids, face, behind the ears
- Mechanism
- Venous congestion above the point of obstruction
- Strangulation
- Typically prominent
- Complete hanging
- Typically sparse or absent
Common questions
Why do complete and incomplete hanging differ in petechial findings?+
In complete hanging the body's weight often occludes both arterial and venous vessels rapidly, cutting off inflow before congestion builds, whereas in incomplete hanging and manual strangulation venous return is blocked while arterial inflow continues longer, raising capillary pressure and producing more petechiae.
Can petechial haemorrhages alone confirm strangulation as the cause of death?+
No. They are a supporting finding that must be read together with neck dissection findings, ligature or finger-pressure marks, and the overall autopsy picture, since petechiae can occur in several non-homicidal mechanisms of death.
Related terms
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- Hyoid Bone Fracture
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- Ligature Mark
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- Paltauf's Spots
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- Parchmentisation
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