Microvasculature of the mouse eye: Scanning electron microscopy of vascular corrosion casts

Purpose

For drug safety assessment, ophthalmic fundus examination is of diagnostic importance in experimental animals. Interim blood samples are usually collected from the orbital venous sinus in the mouse. This report characterizes the angioarchitecture of the mouse eye.

Methods

In 10 mice, the microvasculature of the eyes of was investigated using scanning electron micrographs of corrosion casts.

Results

The mouse eye was characterized as having a rich vasculature with many thick retinal arteries and a well-developed orbital venous sinus. The eye receives its primary blood supply from the external ophthalmic artery, which is divided into three branches: the central retinal artery, as well as the medial and lateral long posterior ciliary arteries. The central retinal artery is divided into 8-9 radiating retinal arteries. The mouse has an orbital venous sinus around the orbit rather than a well-developed orbital venous plexus in the retrobulbar space as is in the rat. The orbital venous sinus is formed by the episcleral veins, the ophthalmic vein, the superior palpebral vein, inferior palpebral vein and numerous anastomotic veins among these veins.

Conclusions

The mouse ocular vasculature is quite similar to that of rats. It is recommended that the best location for insertion of a capillary tube for collecting blood is in the lateral canthus around the eye where the sinus is larger and is most readily accessible. Functional significance of the vascular patterns of the eye is discussed.