Flashes of light in your vision, medically known as photopsias, are brief sensations of light appearing without an external source. These can manifest as streaks, sparks, or lightning-like sensations. While concerning, these visual disturbances are common. Understanding their nature helps address potential underlying causes.
Common Benign Causes
Many instances of flashes of light are linked to normal changes within the eye. One frequent cause is Posterior Vitreous Detachment (PVD), involving the vitreous gel, a clear, jelly-like substance filling the eye. As a person ages, this vitreous gel naturally liquefies and shrinks, separating from the retina at the back of the eye. This separation can cause the vitreous to tug on the retina, leading to flashes, often described as streaks of light, noticeable in peripheral vision or darker environments. PVD is a common age-related condition, typically not requiring treatment or causing pain.
Another common benign cause is ocular migraines, also known as retinal migraines or migraine with aura. These flashes are distinct from vitreous issues, often appearing as shimmering, zigzag lines, or geometric patterns. Ocular migraine symptoms usually affect one eye, lasting 5 to 60 minutes. These visual disturbances may or may not be followed by a headache.
Urgent Medical Causes
While many flashes are harmless, some indicate serious conditions requiring immediate attention. A retinal tear occurs when shrinking vitreous gel pulls too strongly on the retina, causing a tissue break. This tearing leads to flashes, often described as lightning streaks or stars. If not addressed, fluid can pass through the tear, potentially leading to a more severe condition.
A retinal detachment is a medical emergency where the retina pulls away from its normal position. This can progress from an untreated retinal tear or occur independently. Flashes can be a precursor or accompanying symptom of retinal detachment. When the retina detaches, it loses oxygen and nutrient supply, leading to permanent vision loss if not treated promptly.
When to Seek Medical Attention
Seek prompt medical attention for certain warning signs associated with flashes. A sudden onset or increase in flash frequency and intensity warrants immediate evaluation. New floaters, especially a shower accompanying flashes, are also concerning.
Other serious indicators include a “curtain” or “veil” sensation in your field of vision, or any peripheral vision loss. Flashes after head or eye trauma, or any sudden, significant vision change, also require urgent assessment by an eye care professional. Timely evaluation can prevent serious vision loss.
Diagnosis and Treatment Approaches
When visiting an eye doctor for flashes, a comprehensive eye exam determines the cause. This typically involves dilating pupils with eye drops for a clear view of the retina. This examination helps identify any tears, detachments, or other retinal issues.
For benign causes like Posterior Vitreous Detachment (PVD), no specific treatment is usually required; the condition is primarily monitored. The flashes and floaters associated with PVD often become less noticeable over a few weeks or months. Ocular migraines are managed like other migraines, often by identifying and avoiding triggers, sometimes with medication.
For urgent conditions, early intervention is important. Retinal tears can be treated with procedures like laser photocoagulation or cryopexy. Laser treatment creates small burns around the tear, forming scars to seal the retina and prevent fluid accumulation. Cryopexy uses a freezing probe to create scar tissue, achieving a similar sealing effect.
Retinal detachment often requires surgical intervention. This may include vitrectomy (removing and replacing the vitreous gel), pneumatic retinopexy (injecting a gas bubble), or scleral buckling (placing a band around the eye). These treatments aim to reattach the retina and prevent permanent vision loss.