Cortical Fusi
Definition
Air-filled spaces within the cortex of the hair shaft, most common near the root end. Their size, shape, and distribution are minor comparison features in forensic microscopy.
- Location
- Cortex of the hair shaft
- Composition
- Air-filled spaces
- Most common near
- Root end
- Forensic role
- Minor comparison feature in hair microscopy
Common questions
Why are cortical fusi only a minor feature rather than a primary identification point?+
Their size, shape, and distribution vary naturally along a single hair and between hairs from the same person, so they lack the consistency needed to individualise a sample and are used only to add weight alongside more stable features.
Can cortical fusi be confused with air bubbles introduced during mounting?+
Yes, mounting medium can trap air bubbles that resemble natural fusi, which is why examiners check the mount preparation and compare against multiple hairs before treating an apparent fusus as a genuine structural feature.
Related terms
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