Although light sensitivity and photophobia is a neurological symptom at its core, we also know it has a significant effect on the eyes. This makes eye-related disorders, like glaucoma, equally vulnerable to the onset of light sensitivity. In this post, we explain how people with glaucoma experience this issue differently when compared with other conditions.
The Effect of Light Sensitivity on Glaucoma
There are multiple types of glaucoma, but all of them generally cause dysfunction within the optic nerve. This can result in symptoms such as:1
- Loss of peripheral vision
- Tunnel vision
- Eye pain or tenderness around the eye
- Red eye
- Visual changes (seeing rings around lights or blurred vision)
- Nausea and vomiting
In addition, the optic nerve plays a central role in the development of photophobia because of its connection with the brain. So it should come as no surprise that patients with glaucoma can feel an intense aversion to light, often as an early warning sign. The question of whether it will actually cause light sensitivity for you is hard to answer, but it is estimated to impact between 15-50% of those with glaucoma.2,3
One of the biggest side effects of glaucoma-related photophobia is glare sensitivity that can be worsened by sunlight as well as fluorescents, LED or other artificial light. This makes it difficult for patients to perform normal activities of living such as driving at night and going outside. Experts have even suggested that problems with glare and reflection may be one of the earliest indicators of disease progression. Curiously, individuals have also reported “seeing too much light” which may be a sign of excessive brightness and photophobic discomfort.2
Adjusting to Light & Dark Environments
Light exposure also negatively impacts the way glaucoma patients visually adapt to their environments. A recent study showed that swift changes in brightness contributed to a lower contrast sensitivity for glaucomatous eyes versus healthy eyes; this ultimately reduced visual focus and brought on other symptoms.4 This may be one reason why those with the condition often complain that their eyes struggle to adjust after going from a dark to a bright environment or vice versa.
Blue Light Sensitivity
It has been well established that certain wavelengths or colors of light activate sensitive cells in the eye, which can contribute to the strong reactions from a photophobic person. Similarly, those with glaucoma may also have visual difficulties when exposed to this type of light—in particular blue light. In fact, glaucomatous pupils that were in an advanced or severe stage of impairment were more sluggish to recover after exposure to blue light.5 This could possibly explain why those with glaucoma have difficulty staring at computer or smartphones screens as a result of the high percentage of blue light from those sources.
Amazingly, it’s even been suggested that light exposure, especially to shortwave blue light, may contribute to the worsening of glaucoma because of retinal cell death!6
Another unique occurrence of photophobia happens with children who develop congenital or infantile glaucoma, usually within a year of being born. This specific type also leads to increased pressure within the eye, which causes the eyes to enlarge and thus triggers issues like sensitivity to light and excessive tearing.
Glaucoma, Migraine and Light Sensitivity
Given that an increase in ocular pressure is a common feature of glaucoma which influences the optic nerve, patients can experience headache as a symptom. Migraine has also been connected to glaucoma, although it is unlikely be a direct cause. Still, it might affect up to one-fifth of patients and even that number may be under-reported. Researchers have also noted that the risk for migraine is noticeably higher for those with normal tension or normal pressure glaucoma as well as a those with a family history of the eye disorder.7,8
Of course, the onset of migraine with glaucoma brings with it all the possible symptoms of a chronic headache disorder including light sensitivity. In fact, as we have often cited, photophobia is the second leading symptom of migraine after head pain. (P.S. If you're interested in reading more stats and facts about photophobia, click here.
Treating Light Sensitivity from Glaucoma
Glaucoma can be a serious disease with long-term consequences; the first step is to receive a proper diagnosis as early as possible from a medical professional. He or she may recommend specific medications, laser treatment or eye surgery to improve glaucomatous symptoms and delay its progression. Unfortunately, these options may also unintentionally worsen light sensitivity too, although the chances are small.
If your photophobia persists, you can consider trying precision-tinted eyewear that filters those wavelengths of light that cause problems for glaucomatous eyes. These glaucoma glasses can make a big difference in how you process light! You can also try a few other expert recommendations from our team by clicking below.
1National Eye Institute. Facts About Glaucoma. 2015 Sept. Retrieved from https://nei.nih.gov/health/glaucoma/glaucoma_facts.
2Hu CX, Zangalli C, Hsieh M, et al. What do patients with glaucoma see? Visual symptoms reported by patients with glaucoma. Am J Med Sci. 2014;348(5):403-9.
3Tidake P, Sharma S. Clinical profile and management of primary open-angle glaucoma patients above 40 years: A rural hospital-based study. Journal of Datta Meghe Institute of Medical Sciences University. 2017; 12(1): 1-6.
4Bierings RAJM, Kuiper M, van Berkel CM, Overkempe T, Jansonius NM. Foveal light and dark adaptation in patients with glaucoma and healthy subjects: A case-control study. PLoS One. 2018;13(3):e0193663. Published 2018 Mar 6. doi:10.1371/journal.pone.0193663.
5Rukmini AV, Milea D, Baskaran M, How AC, Perera SA, Aung T, Gooley JJ. Pupillary Responses to High-Irradiance Blue Light Correlate with Glaucoma Severity. Ophthalmology. 2015 Sep;122(9):1777-85. doi: 10.1016/j.ophtha.2015.06.002.
6Osborne NN, Lascaratos G, Bron AJ, Chidlow G, Wood JP. A hypothesis to suggest that light is a risk factor in glaucoma and the mitochondrial optic neuropathies. Br J Ophthalmol. 2006;90(2):237-41.
7Cursiefen C, Wisse M, Cursiefen S, Jünemann A, Martus P, Korth M. Migraine and tension headache in high-pressure and normal-pressure glaucoma. Am J Ophthalmol. 2000 Jan;129(1):102-4.
8Gramer G, Weber BH, Gramer E. Migraine and Vasospasm in Glaucoma: Age-Related Evaluation of 2027 Patients With Glaucoma or Ocular Hypertension. Invest Ophthalmol Vis Sci. 2015 Dec;56(13):7999-8007. doi: 10.1167/iovs.15-17274.