Dry eye syndrome, also known as keratoconjunctivitis sicca, is a common condition that affects millions of people worldwide. It is characterized by a lack of adequate tear production, leading to discomfort, irritation, eye pain, light sensitivity and blurry vision. While the causes of dry eye can vary, recent studies have shed light on a surprising connection between dry eye and brain injury.
Link Between Dry Eye and Other Conditions
Brain injury, whether it be from a traumatic event like a concussion or a more chronic condition like Parkinson’s or Alzheimer’s disease, 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.
Causes of Dry Eye after Brain Injury
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.
Management of Dry Eye
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
ABOUT THE AUTHOR
Dr. Jacqueline Theis, OD, FAAO is an optometrist with residency training in neuro-optometry, who treats patients with visual complaints and double vision due to brain injury and neurological disease. She has written and lectured international about eye and oculomotor problems after brain injury. You can read more about Dr. Theis HERE.
