ntravitreal injection is a technique used to deliver drugs, viral vectors, or cells directly into the vitreous humor of the eye. The protocol involves anesthetizing the subject (e.g., mouse, rat), positioning it under a microscope, and applying topical antiseptic and anesthetic drops. A fine-gauge needle or microsyringe is then inserted through the sclera at a specific angle to avoid retinal damage. The injection is administered slowly to ensure proper diffusion. After injection, antibiotic drops are applied, and the subject is monitored for potential complications such as inflammation or infection. This method is widely used in ocular research and therapy.