This is a page of tips and suggestions for problems commonly encountered during frozen section, and we hope that each step will provide valuable reminders of good histology practice and aid in troubleshooting in the event of unacceptable results.
1. Tissue Disruption When Sectioning
| Problem | Solution |
| Nicked blade. | Use a new blade in each sectioning session. |
| Choose an ideal cryostat temperature for the specific tissue. | |
| Wait longer for it to equilibrate at the cryostat temperature if the tissue is too firm for sectioning. |
2. Holes
| Problem | Solution |
| Over-freezing/Under-freezing. | Polish the block with a couple of extra turns of the blade to create friction and warm up block by pressing on it with your finger (5-10 seconds). |
| Make sure the cryostat reached the selected temperature before transferring the tissue, in some cases adding a heat sink to block can help. | |
| Minimize the time between tissue dissection and freezing. After dissection, quickly freeze the tissue. |
3. Ice Crystals
| Problem | Solution |
| Due to slow freezing of tissue. | Freeze tissue faster. The faster the freeze, the smaller the ice crystals and the less damage to tissue. |
| Avoid freezing fatty tissue surrounding the tissue of interest. | |
| Work with smaller tissue - optimally tissue should be 0.5 x 0.5 x 0.3 cm or less. | |
| Do not use tissue larger than the diameter of the chuck. | |
| Dry the surface of the tissue by pressing with gauze before making the block. | |
| After freezing, do not store tissue at -20°C for more than an hour. |
4. Air Bubbles
| Problem | Solution |
| May be trapped under coverslips, which cause the tissue to dry out. | Keep the coverslips in the cryostat. |
| Make sure an appropriate amount of resin is applied. | |
| Gently move air bubbles off the slide with finger or tweezers. | |
| Moving the coverslip up and down can also help to spread the tissue. |