When cedarwood oil is used for clearing, it must be followed by which solvent?

• A. Xylene
• B. Ethanol
• C. Water
• D. Isopropanol

Answer: (A)

Cedarwood oil serves as a clearing agent to render tissue transparent, but it isn’t compatible with paraffin by itself. After clearing with cedarwood oil, you need a solvent that can displace the oil and transition the tissue to the paraffin embedding medium. Xylene is the standard choice because it effectively replaces cedarwood oil in the tissue and mixes with paraffin, allowing proper infiltration. Ethanol, water, and isopropanol don’t reliably remove the oil or prepare the tissue for paraffin infiltration, so they aren’t suitable immediately after cedarwood oil.