Fixation techniques for fine needle aspiration biopsy smears prepared off site.

摘要

OBJECTIVE: To identify a simple, cost-effective, reliable fixation method for fine needle aspiration biopsy (FNAB) yielding a specimen suitable for mail transport. STUDY DESIGN: Smears prepared from 59 FNABs of surgical specimens were fixed by continuous fixation in 95% ethanol, spray fixation, air drying, ethanol fixation for either 5 minutes or 4 hours followed by spray fixation, or fixation in 95% ethanol for either 30 minutes or 4 hours followed by air drying. Fixation was graded as unsatisfactory, suboptimal, average, good or excellent. RESULTS: Of smears continuously fixed in ethanol, 96.6% were graded as excellent. Of smears fixed in ethanol followed by spray fixation, 93.2% were excellent irrespective of fixation time; 64.4% of spray-fixed smears were excellent and 27.1% good. Of air dried smears, 93.2% were unsatisfactory or suboptimal; 83.0% of smears fixed in ethanol for 30 minutes and 74.6% of smears fixed for 4 hours prior to air drying were unsatisfactory or suboptimal. CONCLUSION: Fixation of smears in 95% ethanol followed by spray fixation produces excellent results, comparable to those with continuous fixation in ethanol. Spray fixation is generally good but not consistently excellent. Air drying or fixation in ethanol followed by air drying yields unsatisfactory or suboptimal results in most cases.