Ultra-Rapid Microwave/Variable Pressure-Induced Histoprocessing: Description of a New Tissue Processor

We describe a new method of ultra-rapid histoprocessing that reduces the processing times for needle and endoscopic biopsies to 30 min and that of other surgical biopsy tissue blocks of up to 4 mm thick to 120 min. The MicroMED U R M Histoprocessor, which combines microwave irradiation with precise computer control of power, time, temperature, vacuum, and pressure, when used with a 1-step dehydrating/clearing reagent, consistently produces rapidly processed tissues with optimal cytomorphology and improved tissue sectioning properties. Staining properties are excellent with no deleterious effects on routine staining, histochemistry, or immunohistochemistry. This new processing technique represents a major change from conventional tissue processing and eliminates the use of hazardous reagents such as xylene. The ease of application and speed of this technique can significantly reduce turnaround times in diagnostic laboratories. (The J Histotechnol 21:219–224, 1998)