The retina is a neurosensory tissue for visual function. Since a substantial amount of oxygen is needed for visual function, the retina is known as one of the highest oxygen demanding tissues in the body1. The retina is susceptible to vascular diseases as oxygen is delivered through blood vessels. Various types of vascular diseases, such as diabetic retinopathy and retinal blood vessel (veins or arteries) occlusion, can induce retinal ischemia. To investigate pathological mechanisms of retinal ischemia, reproducible and clinically relevant experimental models of retinal ischemia are considered necessary. Middle cerebral artery occlusion (MCAO) by insertion of an intraluminal filament is the most generally utilized method for the development of in vivo rodent models of experimental cerebral ischemia2,3. Due to the proximity of the ophthalmic artery (OpA) to MCA, MCAO models are also used simultaneously to understand the pathophysiology of retinal ischemia4,5,6. To induce cerebral ischemia along with retinal ischemia, long filaments are typically inserted through incision of the common carotid artery (CCA) or the external carotid artery (ECA). These methods are difficult to perform, require a long time to complete the surgery (over 60 minutes for one mouse), and lead to high variabilities in the outcomes after the surgery7. It remains important to develop a better model to improve these concerns.
In this study, we simply used short transient bilateral CCA occlusion (tBCCAO) with needles and a clamp to induce retinal ischemia in mice and analyzed typical results of ischemic injuries in the retina. In this video, we will give a demonstration of the tBCCAO procedure.