Knowledge Base › Troubleshooting Atlas › Frozen section
Ice-crystal artifact (frozen section)
Also known as: freezing artefact, Swiss-cheese holes
What it looks like
Clear holes/vacuoles and a lacy, distorted architecture in the frozen section.
Where it usually appears: Slow freezing, water-rich tissue, or a warm cryostat.
Likely causes
- Too-slow freezing allowing large ice crystals to form
- Water-rich tissue
- Cryostat/chuck not cold enough
- Refreezing thawed tissue
Immediate checks
- Freeze rapidly (cold chuck, freezing spray or fast-freeze bar)
- Confirm cryostat temperature is adequately low
- Blot excess fluid before freezing
Corrective action
- Re-freeze a fresh piece rapidly
- Trim to a smaller piece for faster freezing
Preventive action
- Use rapid-freezing methods
- Keep the cryostat at temperature and serviced
- Avoid thaw-refreeze cycles
This atlas is for educational purposes for laboratory professionals. It does not replace your institutional SOPs, manufacturer instructions, validated protocols or pathologist judgment. Adapt any action to your laboratory and equipment.
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