Drug Delivery across Blood-Brain Barrier (IMAGE) Mass Eye and Ear Caption Drugs used to treat a variety of central nervous system diseases may be administered through the nose and diffused through an implanted mucosal graft (A, in red) to gain access to the brain. Under normal circumstances, there are multiple layers within the nose that block the access of pharmaceutical agents from getting to the brain including bone and the dura/arachnoid membrane, which represents part of the blood-brain barrier (B). After endoscopic skull base surgery (C), all of these layers are removed and replaced with a nasal mucosal graft, which is 1,000 times more porous than the native blood-brain barrier. Consequently, these grafts may be used to deliver very large drugs, including proteins, which would otherwise be blocked by the blood-brain barrier. Credit Garyfallia Pagonis and Benjamin S. Bleier, M.D. Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.