Imaging review of ocular and optic nerve trauma

Traumatic Brain Injury-Related Optic Nerve Damage

Vision disorders are associated with traumatic brain injury (TBI) in 20%-40% of clinical cases and involve a diverse set of potential symptoms that can present acutely or chronically. Due to its structure and position, the optic nerve is vulnerable to multiple forms of primary injury, which can result in traumatic optic neuropathy (TON). Multiple studies have shown that the optic tract may also be injured during TBI, though data regarding the temporospatial resolution of injury to the optic nerve are sparse. We evaluated the time course of optic nerve injury and visual impairments in our closed head impact acceleration mouse model of mild TBI (mTBI) designed to mimic repetitive injuries experienced in the context of sport. Our results show that inflammation and gliosis occur acutely in response to injury. Additionally, indications of optic nerve degeneration and functional loss of vision beginning at 1-month postinjury, and retinal ganglion cell loss at 7 months, revealed that the degeneration is continuous and permanent. Together, this study demonstrated that the optic nerve is vulnerable to damage during mTBI, which can cause TON and vision loss. These findings will be important for clinicians to consider to determine whether optic nerve is injured in the TBI patients with vision problems.

Non-lethal weapon: Injury patterns and imaging correlates for firearm alternatives

Law enforcement officers have adopted the use of non-lethal weapons to mitigate civilian casualties incurred by firearm use over recent years and decades. These weapons include, but are not limited to, TASER, beanbag rifles, pepper spray, tear gas, and Flash-ball guns. Nonetheless, severe injuries and even deaths do occur with use of these weapons, in rare instances. This review aims to comprehensively discuss these cases and associated injuries, as well as their according findings on imaging studies. It will also examine how often injuries occur in situations with non-lethal weapons.

CT Features of Posttraumatic Vision Loss

Clinical evaluation of patients with trauma is challenging, especially in the presence of neurologic injuries. Vision loss after trauma is a harmful and usually overlooked consequence that may be avoided with a prompt and accurate intervention. Head CT is commonly performed in patients with trauma. However, radiologists may be unfamiliar with the CT findings associated with injuries that may affect eyesight. Understanding the visual pathway anatomy and its critical landmarks is paramount for recognizing these findings. This article describes the use of head CT to evaluate the visual pathway to help avoid vision loss in patients with trauma. Injuries are presented in terms of those affecting the globe (rupture, hemorrhage, and lens trauma), optic nerve (direct and indirect traumatic optic neuropathy), orbit (orbital compression syndrome), and vasculature (traumatic carotid-cavernous sinus fistula and posterior cerebral artery injury or ischemia). Techniques for measuring the globe on CT to assess for injury are illustrated. Indications for screening CTA of the head and neck in patients with suspicion for blunt traumatic vascular injury are summarized. Emphasis is placed on the CT findings that warrant an emergency intervention to prevent traumatic visual impairment.