Dry Eye Syndrome is a form of ocular surface disorder affecting millions of people worldwide. Characterized by symptoms like occasional blurry vision, tearing, gritty feeling, and redness, dry eye is a condition that often goes unrecognized but can lead to significant discomfort for sufferers. The condition is marked by inadequate tear production, leading to discomfort, irritation, eye pain, light sensitivity, and blurred vision. While the causes of dry eye may vary and can include increasing age, gender (female), hormonal changes, and inflammatory diseases like thyroid or Sjogren's disease, recent studies have revealed a surprising connection between dry eye and brain injury.
Connection Between Dry Eye and Other Health Issues
Brain injury, whether it be from a traumatic event like a concussion or a more chronic condition neurologic condition like Parkinson’s or Alzheimer’s disease, neurologic dysfunction has been found to have a significant impact on the ocular surface and tear film. In fact patients with a history of traumatic brain injury have a higher rate of dry eye than the general population.1 This connection between the brain and the eyes is a complex and fascinating area of research that is still being explored, and often overlooked by many doctors.
Reasons for Dry Eye following Brain Trauma
One of the main ways brain injury can lead to dry eye is through damage to the autonomic nervous system (ANS). The ANS controls the involuntary functions of the body, including tear production. When the brain is injured, it can disrupt the normal functioning of the ANS, leading to decreased tear production from the lacrimal gland and thus dry eye symptoms. Additionally, damage to parts of the brainstem can also reduce the average blink rate, as can be seen in Parkinson’s disease and Progressive Supranuclear Palsy, further contributing to dry eye disease. Finally, a commonly frustrating condition can occur in brain injury when there is trigeminal nerve damage or trigeminal neuralgia, which can lead to central neuropathic eye pain, a condition where the patient feels eye pain and dry eye symptoms, but the ocular health itself is normal.2
Brain injury can also affect the regulation of inflammation in the body. Inflammation plays a crucial role in the development and progression of dry eye, as it can disrupt the delicate balance of tear production and composition. Studies have shown that brain injury can lead to increased levels of pro-inflammatory cytokines, which can further exacerbate dry eye symptoms.
Furthermore, the medications commonly used to treat brain injuries can also contribute to dry eye. Many of these medications, such as anticholinergics, antidepressants, anticonvulsants, antipsychotics, and antiparkinson drugs3 may have a drying effect on the body and can decrease tear production. This can make dry eye symptoms even more severe for individuals already dealing with the effects of a brain injury.
And of course - sleep matters! Just two nights of disrupted sleep can cause/exacerbate dry eye.
Handling Dry Eye Conditions
So, what can be done to manage dry eye in individuals with brain injuries? Firstly, it is crucial to seek medical attention and receive a proper diagnosis. A comprehensive eye examination can help identify the underlying causes of dry eye and determine the most appropriate treatment plan.
Treatment options for dry eye may include artificial tears, which can help lubricate the eyes and provide relief from dryness, as well as eyelid hygiene like warm compresses and eyelid wipes. To help reduce ocular surface inflammation oral supplementation with omega 3s4 and lutein5 can also help with symptoms of dry eye and glare sensitivity. In more severe cases, prescription medications or procedures may be necessary to address tear production issues. Additionally, lifestyle modifications such as avoiding environmental triggers, using humidifiers, and decreasing autonomic stress can also help manage dry eye symptoms.
The connection between dry eye and brain injury is a complex and multifaceted one. While more research is needed to fully understand the mechanisms at play, it is clear that brain injury can have a significant impact on tear production and ocular health. By recognizing this connection and seeking appropriate treatment, individuals with brain injuries can find relief from dry eye symptoms and potentially improve their overall brain health and quality of life.
References
Lee CJ, Felix ER, Levitt RC, et al. Traumatic brain injury, dry eye and comorbid pain diagnoses in US veterans. Br J Ophthalmol. 2018;102(5):667-673. doi:10.1136/bjophthalmol-2017-310509
Diel RJ, Mehra D, Kardon R, Buse DC, Moulton E, Galor A. Photophobia: shared pathophysiology underlying dry eye disease, migraine and traumatic brain injury leading to central neuroplasticity of the trigeminothalamic pathway. Br J Ophthalmol. 2021;105(6):751-760. doi:10.1136/bjophthalmol-2020-316417
Askeroglu U, Alleyne B, Guyuron B. Pharmaceutical and herbal products that may contribute to dry eyes. Plast Reconstr Surg. 2013;131(1):159-167. doi:10.1097/PRS.0b013e318272a00e
Epitropoulos AT, Donnenfeld ED, Shah ZA, et al. Effect of Oral Re-esterified Omega-3 Nutritional Supplementation on Dry Eyes. Cornea. 2016;35(9):1185-1191. doi:10.1097/ICO.0000000000000940
Jia YP, Sun L, Yu HS, et al. The Pharmacological Effects of Lutein and Zeaxanthin on Visual Disorders and Cognition Diseases. Molecules. 2017;22(4):610. Published 2017 Apr 20. doi:10.3390/molecules22040610