Urgent Manual Processing
From time to time it is necessary to prepare a stained section for urgent diagnosis. Usually a frozen or cryostat section is used, but sometimes they are inadequate and a higher quality paraffin section is required.
| Urgent processing | |
| Tissue preparation | |
| Thickness | No more than 1 mm thick. Place directly into Carnoy's fluid. |
| Area | 10 mm × 20 mm. |
| Unfixed tissue | This schedule was often used with fresh tissues when a paraffin section was needed for an urgent diagnosis. |
| Times | All times in processing fluids for this schedule are for tissues 1 mm thick or less. Thicker tissues will not process. |
| Clearing agent | Xylene should be used. |
| Agitation | The gentle agitation, and a degree of warmth, required for this schedule was obtained by using a small container with a secure cap and putting it in a pocket, preferably close to the body. Natural movements and bodily heat were all that was required. |
| Visual control | The tissue should be examined periodically to check progress, particularly when in the clearing agent as poor dehydration will show up as opaque areas. |
| Processing time | This schedule requires about 4-5 hours to complete from tissue selection. The extra time in the first wax is required to bring the container up to temperature. The tissue should be gently blotted at each fluid change (except waxes) to minimise carry over. |
