Knowledge Base › Troubleshooting Atlas › Tissue processing
Under-clearing
Also known as: incomplete clearing, cloudy on infiltration
What it looks like
Poor wax infiltration and soft blocks because alcohol was not fully replaced by clearant before wax.
Where it usually appears: Short clearing steps, exhausted clearant, or fatty tissue.
Likely causes
- Insufficient clearing time
- Exhausted or diluted clearing agent
- Residual water/alcohol from incomplete dehydration
- Fatty tissue needing more clearing
Immediate checks
- Check clearant rotation and change overdue stations
- Confirm dehydration was complete
- Extend clearing for fatty tissue
Corrective action
- Reprocess affected tissue through fresh clearant and wax
Preventive action
- Maintain clearant change schedule
- Ensure full dehydration first
- Longer schedule for fatty/dense tissue
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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