Long-Term Anatomical Effects of Increased Intracranial Pressure on Optic Nerve Sheath Dilation

The purpose of this study was to investigate the long-term anatomical effects of mild traumatic brain injury (mTBI) and increased intracranial pressure (ICP) on optic nerve sheath diameter (ONSD) dilation by analyzing optic nerve sheath fibers 30 days after increasing ICP in a swine model. Our lab has previously demonstrated that a patient history of mTBI is associated with ONSD dilation, post Valsalva, that can be visualized on ultrasonography. We investigated the anatomical etiology for ONSD dilation and discovered a statistically significant thinning of fibers connecting the optic nerve and optic nerve sheath immediately after injury. The long-term anatomical effects of these fibers have not been previously studied and may hold important implications about post-traumatic recovery mechanisms.