We have some rats being sacrificed for access to their brains for immunohistochemsitry. But since they are already being sacrificed, I was wondering how to go about removing their eyes as well for a side project.
Dear Carly,
I study the anatomy of the optic nerve as well as the eye, so I prefer to use small iridectomy scissors (Student Vannas) for rat work. Depending on the age of the animal, the connective tissue surrounding the eyeball and the optic nerve can be pretty tough. The approach is the same as described by Victor, but you can easily run one tip of the scissors along the eyeball and make long cuts. The sclera is very tough, so you usually don't cut through it by mistake. I pinch a bit of the connective tissue up with number 5 forceps in my left hand, clip the little "pleat" that forms in the connective tissue to give access for the scissor blade, keep holding the connective tissue with the forceps at the same point, and then cut both counterclockwise and clockwise from the initial point around the eyeball. Pull on the forceps slightly to retract the eye towards the midline of the head, and then use the tips of the scissors to cut the optic nerve. I find that this method helps keep the optic nerve head intact.
If they are very large rats you may not be able to cut all the way around the eye with the first cuts. That's OK. Just cut as far as you can quickly to expose the nerve, cut through the nerve, and then finish cutting through the connective tissue. Since you always have the forceps in your left hand to hold the connective tissue, this is easy to do.
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