Often called a cerebrovascular accident or, more bluntly, a “brain attack”, strokes represent a scary medical emergency. They feature symptoms that often develop without warning and that can become lifelong problems. Even so-called ministrokes, or transient ischemic attacks (TIA), pose a serious concern.

Light sensitivity, also known as photophobia, has been identified as a regular symptom of strokes and ministrokes. We explore how people experience this sensitivity to their environment.

Likelihood of Photophobia During and/or After Stroke

With the prevalence of other physical complications, light sensitivity can be overlooked in the catalog of symptoms that occur as part of a stroke or TIA. As a result, we do not currently have a good understanding of how often these sensitivities present themselves during the initial phases. Headache and eye/visual changes both can appear suddenly at the onset of a stroke, and so it is possible that photophobia can accompany those issues too.

Clinical research offers more insight into photophobia in the post-stroke period. Studies have shown that sensitivity to bright light can affect between 5-10% of people with TIA, and women may have a greater risk.¹ Typically, it develops alongside headache and migraine-like symptoms as well, which are reported by as much as one-third of patients.² Among those with headache after a stroke or ministroke, estimates show that 13-30% are likely to deal with painful sensitivity to light.³ These headaches, and related symptoms, may persist for years or even the rest of your life, reinforcing just how damaging a stroke can be.

Researchers have further identified astheno-emotional syndrome (AES) as a common experience in the months and years following a stroke. This grouping of symptoms includes cognitive issues like mental fatigue and memory difficulties along with physical complaints such as light and sound sensitivity. They are often “hidden” symptoms that can have a dramatic impact on daily quality of life for stroke patients.⁴ This is consistent with the feelings of many who live with photophobia—their symptoms are invisible and regularly misunderstood by others, unpredictable depending on the environment, and harmful to their overall wellbeing.

Features of Post-Stroke Sensitivity to Light

There does not appear to be any major differences between a person who develops photophobia after a stroke versus any other light-sensitive condition. It regularly occurs with headache, which often presents as tension-type headache, as well as other sensory sensitivities (namely to sound, also known as phonophobia). It can certainly be experienced as “pain due to light exposure”, in addition to numerous other reactions, such as:

• Headache or migraine attack from light exposure
• Eye symptoms like squinting, eye strain, eye pain, redness
• Avoidance of or lower threshold for bright light
• Anxiousness, panic and other emotional symptoms
• Pattern glare sensitivity, or ocular discomfort when viewing certain visual stimuli

Research has suggested that people who experience a stroke may be more susceptible to “pattern glare,” which is an extension of this general hypersensitivity to their environment. Specifically, they feel discomfort to striped patterns and can therefore endure elevated levels of visual stress, headaches, eye strain, and photophobia.⁵ People with other conditions, namely migraine and epilepsy, have reported similar issues with patterned images and lighting. This may even indicate a different reaction from the brain when compared with the typical migraine and photophobia response.

The same types of light sources can trigger symptoms too—from screens and fluorescent lighting to bright outdoor light. The presence of post-stroke headache and/or migraine symptoms in particular indicates that they are likely less tolerant of bright light and may be negatively activated by specific wavelengths of blue light too, similar to others with photophobia. We hope to see more research in the future to determine exactly how light triggers and light sensitivity after a stroke may differ from other common causes of photophobia.

Other Risk Factors for Photophobia after Stroke

As we mentioned previously, women may have a higher risk for light sensitivity following a stroke or ministroke, but what other risk factors exist?

One of the biggest determinants that can increase the likelihood of post-stroke photophobia is the presence of a comorbid condition. Persistent headache after stroke or TIA is perhaps the most common and has even been declared a “secondary headache” by the International Classification of Headache Disorders. Patients who already have migraine prior to suffering a stroke are at greater risk for developing or having recurring headaches and related symptoms after the attack. There is even evidence that people diagnosed with migraine with aura, particularly women, are generally at greater risk for ischemic stroke—although numerous other factors (including behavioral choices) likely play a key role too. Still, it illustrates the deep connections that photophobia has with migraine and headache disorders and how it can evolve throughout the patient experience. You can be light sensitive prior to having a stroke, and it can continue or change during the recovery phase and long afterward.

In addition to headache and migraine, dry eye disease has been linked to negative outcomes after stroke;⁶ and even though it may yield atypical experiences, we still must account for the large percentage of people who have light sensitivity as a result of dry eye disease.

Stroke vs Hemiplegic Migraine

Hemiplegic migraine is a particular type of migraine with aura featuring symptoms that mimic a stroke. This includes short-term motor weakness, numbness, or even paralysis (typically on one side). Although it is not actually a stroke and is instead a migraine disorder, its proximity to the experiences of stroke patients make it worth mentioning. Plus, as it is a form of migraine with aura, it also carries the elevated stroke risk that non-hemiplegic migraine with aura does.⁷ And photophobia represents a huge part of the equation.

In fact, this sensitivity to light occurs at the same rate as other migraine types, specifically for 85-90% of patients. Even actual head pain is reported less often when compared with photophobia! Visual aura and other disturbances also present at a staggering rate for those with hemiplegic migraine, only compounding the total visual and neurological impact it can have.

Improving Light Sensitivity after Stroke or TIA

Many of the same therapeutic options for general photophobia can be used to improve these symptoms after stroke. Certainly it is important to get back out into the light, rather than avoid it altogether or wear sunglasses indoors—both of which can intensify photophobia over time and lead to negative social and emotional outcomes. Also, evidence shows that some light, particularly natural light, can help reduce fatigue and depression as well as improve sleep after a stroke.⁸ So complete avoidance should not be an option.

The combination of physical therapy and/or occupational therapy can be effective tools in supporting stroke patients and improving their health and wellbeing in all facets of their life. This includes helping address lingering post-stroke symptoms such as light sensitivity.

More and more physical therapists (PTs) and occupational therapists (OTs) are recommending tools like TheraSpecs therapeutic glasses for light sensitivity and other symptoms triggered by light. With a variety of lens options available, TheraSpecs filter the wavelengths of light associated with different brain responses. For example, they offer a range of FL-41 glasses that cut out 480-520nm light, which research has shown to trigger or aggravate photophobia, migraine, and headaches, and they can help people with stroke-related sensory issues too. In particular, if you are experiencing recurring light-sensitive headaches or migraine attacks with photophobia, TheraSpecs are the best option for relief and protection against harmful blue light.

One TheraSpecs user, whose multiple strokes left her with debilitating migraine episodes, described the glasses as “migraine slayers” that help lessen her triggers and enable more participation in activities. You can read her story here.

TheraSpecs also offers Z-Blue, which blocks an entirely different part of the light spectrum that is associated with hypersensitivity to visibly flashing lights and repeating patterns. This lens option can be a great choice for people without the typical light sensitivity response that leads migraine, headaches, and photophobia, but still find lighting and their environment visually problematic.

Lastly, we always recommend working with your care team to identify the best treatment plan for your needs. Of course, you can always find research-supported treatments for photophobia and home remedies on our blog.

Read More: Photophobia Treatments ➜

References:

¹​​Yu AYX, Penn AM, Lesperance ML, et al. Sex Differences in Presentation and Outcome After an Acute Transient or Minor Neurologic Event. JAMA Neurol. 2019;76(8):962–968. doi:10.1001/jamaneurol.2019.1305

²​​Oliveira FA, Sampaio Rocha‐Filho PA. Headaches attributed to ischemic stroke and transient ischemic attack. Headache: The Journal of Head and Face Pain. 2019;59(3):469-476. doi:10.1111/head.13478.

³​​Harriott AM, Karakaya F, Ayata C. Headache after ischemic stroke. Neurology. 2019;94(1). doi:10.1212/wnl.0000000000008591.

⁴​​Carlsson G, Möller A, Blomstrand C. A qualitative study of the consequences of 'hidden dysfunctions' one year after a mild stroke in persons Disability and Rehabilitation. 2004;26(23):1373-1380. doi:10.1080/09638280400000211.

⁵​​Beasley IG, Davies LN. Susceptibility to pattern glare following stroke. Journal of Neurology. 2012;259(9):1832-1839. doi:10.1007/s00415-012-6418-5.

⁶​​Küçük EB, Küçük E, Kaydok E, Zor KR, Biçer GY. Dry Eye in chronic stroke patients with hemiplegia: A cross-sectional study. Topics in Stroke Rehabilitation. 2020;27(8):630-635. doi:10.1080/10749357.2020.1757347.

⁷​​Eikermann-Haerter K, Hyun Lee J, Yuzawa I, et al. Migraine mutations increase stroke vulnerability by facilitating ischemic depolarizations. Circulation. 2012;125(2):335-345. doi:10.1161/circulationaha.111.045096.

⁸​​West A, Simonsen SA, Jennum P, et al. An exploratory investigation of the effect of naturalistic light on fatigue and subjective sleep quality in stroke patients admitted for rehabilitation: A randomized controlled trial. NeuroRehabilitation. 2019;45(2):187-200. doi:10.3233/nre-192752.

Last updated 20th Mar 2024