Comparison of Fixatives for Histologic Evaluation of the Canine Eye

Abstract

We describe several methods for the handling, fixation, and processing of canine eyes, as well as the light microscopic results of these efforts. Fixatives included Zenker and Bouin, 4% formaldehyde-1% glutaraldehyde, and 2% and 6% solutions of glutaraldehyde. In some techniques the globe was injected with fixative; in others, a window was cut into the eye or ocular tissues were dissected and separated to facilitate fixation. Processing included ethyl or isopropyl alcohol dehydration; all eyes were embedded in paraffin. Best overall morphology was seen in specimens fixed in Zenker fluid for 5 to 8 hr and dehydrated initially in isopropyl alcohol. There was superior retinal detail with acceptable morphology of the cornea, iris and lens. Advantages and disadvantages of various techniques and common artifacts are discussed. (The J Histotechnol 14:251, 1991)

Keywords:

• canine eye
• fixation
• ocular tissue
• paraffin sections
• tissue processing