Why does light become painful?
There are a lot of endings of the trigeminal nerve in the anterior parts of the eye. When the cornea or iris is irritated, any constriction of the pupil in response to light increases the pain - hence the pain and the desire to close the eyes. The second mechanism is central: with migraine and some neurological conditions, the excitability of the pathways connecting the retina with the pain centers of the brain increases, and ordinary light is perceived as excessive. The third option is excess light falling on the retina: with a dilated pupil after drops, with a light iris, albinism, and also after cataract removal, while the eye adapts.
- Irritation of the trigeminal nerve endings in the cornea and iris
- Spasm and painful constriction of the pupil
- Increased excitability of the visual pathways in migraine
- Excessive light exposure with a dilated pupil
- Light iris and lack of pigment
Ocular causes
The most common cause is dry eye syndrome: an unstable tear film leaves the cornea unprotected, resulting in pain, a gritty sensation, and sensitivity to light. Corneal erosion following injury from a branch, nail, or lens edge causes severe photophobia with profuse lacrimation. Inflammation of the iris and choroid causes pain, redness around the iris and severe intolerance to light. An ultraviolet burn after welding without a mask or snow in the mountains manifests itself in a few hours with severe pain. Conjunctivitis and keratitis associated with wearing lenses are also common culprits.
- Dry eye syndrome
- Corneal erosion and foreign body
- Keratitis, including due to contact lenses
- Uveitis and iritis
- Ultraviolet eye burn
- Conjunctivitis
- Acute attack of glaucoma
Neurological and general causes
Migraine is accompanied by photophobia in most patients, and sensitivity to light may persist between attacks. Concussion and the consequences of traumatic brain injury often manifest as long-term intolerance to bright light and screens. A dangerous situation is the combination of photophobia with high fever, intense headache, vomiting and neck tension: these are signs of meningitis, which require emergency help. Photophobia occurs with herpes zoster affecting the eye area, with thyroid ophthalmopathy, and as a side effect of a number of medications.
- Migraine
- Concussion and PTSD
- Meningitis and subarachnoid hemorrhage
- Herpes zoster affecting the eye
- Side effects of medications that dilate the pupil
- Anxiety and depressive disorders
- Working in front of a screen for long periods of time without interruptions
Survey
The ophthalmologist assesses visual acuity, examines the anterior segment of the eye at a slit lamp and stains the cornea with fluorescein - this allows you to see erosions and damage that are invisible to the naked eye. Intraocular pressure is measured and the fundus is examined. If the eye is not changed, and photophobia is persistent, an examination by a neurologist is needed to clarify the nature of the headache, the circumstances of the symptom’s appearance and previous injuries. If inflammation of the meninges is suspected, an examination is carried out in a hospital as an emergency.
- Slit lamp examination with corneal staining
- Visual acuity test
- Measuring intraocular pressure
- Fundus examination
- Consultation with a neurologist if the eye picture is normal
- Urgent examination for suspected meningitis
What to do and how to treat it
Treatment is directed to the cause. For dry eyes, moisturizing drops without preservatives are prescribed, screen time is adjusted, and the air is humidified. Corneal erosion heals in a few days under the protection of medications prescribed by a doctor; You cannot wear lenses at this time. Inflammatory eye diseases are treated with drops strictly as prescribed - independent use of hormonal drops is dangerous. For migraines, they work with a neurologist to prevent attacks. Dark glasses are appropriate outdoors, but wearing them constantly indoors increases sensitivity to light and is not recommended.
- Moisturizing drops without preservatives for dryness
- Temporary refusal of contact lenses
- Treatment of inflammation as prescribed by an ophthalmologist
- Sunglasses outdoors, but not all the time indoors
- Interruptions in screen work, decreased brightness
- Prevention of migraine attacks with a neurologist
- Safety glasses when welding and bright sun in the mountains
