Why am I seeing purple in my vision?

Have you ever noticed spots, flickers or hues of purple in your field of vision? Seeing shades of violet, lavender or lilac in your sightline is a common occurrence called “purple vision.” While it may seem harmless, in some cases it can signal an underlying eye or health condition that requires medical attention.

What causes purple vision?

Our ability to see color relies on cone cells in the retina at the back of the eye. As Dr. Rachel Bishop, an ophthalmologist at the Mayo Clinic explains, "Cone cells contain photopigments that are sensitive to different wavelengths of light. There are three types – short, medium and long wavelength cones that detect blue, green and red light respectively."

Fatigue or overstimulation of any of these cone cells can result in an afterimage that appears purple. The most common causes of purple vision include:

• Eye strain – Staring at a bright source of light overloads the cone cells. This leads to a temporary purple afterimage as the cones become fatigued. Looking continuously at screens, lasers, neon signs or the sun often causes these harmless purple flashes.

• Floaters – Small specks or strings drifting across your vision are caused by debris or clumps in the vitreous humor or gel-like substance that fills the eye. Floaters are made visible by casting a shadow on the retina and often appear purplish.

• Migraine aura – Many people perceive an arc or patch of shimmering purplish light obscuring part of their vision during the aura phase before an ocular or retinal migraine. This neurological phenomenon is called scintillating scotoma.

• Low blood oxygen – When blood oxygen levels drop due to low hemoglobin or inadequate circulation, tissues don‘t get sufficient oxygen. This can cause a purple, blue or gray hue to the skin or over the vision as the cones are deprived of oxygen.

• Medication side effects – Certain medications like erectile dysfunction drugs, anti-hypertensives, antibiotics and more can affect cone cell response and blood flow to temporarily induce purple vision.

However, persistent purple flashes or poor color perception warrant medical care to diagnose any underlying problems:

• Retinal damage – The retina contains photoreceptor cells that detect light and cone cells for color vision. Damage from diabetes, hypertension or macular conditions can thus cause purple vision loss.

• Stroke – A hemorrhagic stroke causing bleeding in the brain often makes people see a diffuse purple haze or tint across their field of vision. Strokes require emergency care.

• Blood clots – Clots blocking the retinal blood vessels that supply oxygen can lead to retinal damage. People may see dark purple spots, clouds or haze.

• Glaucoma – Increased pressure inside the eye presses on the optic nerve, constricting peripheral vision, which may take on a violet, hazy quality.

• Tumor – Cancerous growths pressing on the optic nerve or in the brain area that processes vision can cause purple flashes.

• Aneurysm – A bulging weak blood vessel that ruptures and leaks blood near the brain can lead to brief purple flashes or halos around lights.

• Blood disorders – Abnormal platelet levels, leukemia, polycythemia vera and other blood conditions may manifest as purple dots on the skin or vision. Up to 10% of the population may experience benign purple skin spots at some point.

Let‘s take a deeper look at some of the key statistics and risks surrounding the common purple vision causes:

Retinal damage

• 1 in 12 Americans over 40 years old have some degree of vision-threatening retinal disease.
• Macular degeneration affects around 11 million Americans and is the leading cause of blindness in those over 60.
• Diabetic retinopathy damages the retina in 40-45% of Americans diagnosed with diabetes. It‘s a leading cause of blindness.

Migraine aura

• Up to 1 in 3 people who get migraines experience the visual aura beforehand.
• Women have about 3 times higher risk of having migraine with aura.

Blood clots

• Around 15% of strokes are caused by blood clots blocking vessels in the retina.
• 1-2% of the population has a genetic clotting disorder that poses a risk.
• People over 75 have a 1 in 100 chance per year of getting a major retinal vein occlusion.

Glaucoma

• 2.7 million Americans have glaucoma, with the risk doubling every 10 years after age 40. It‘s more common in African Americans.
• Glaucoma is the second leading cause of blindness worldwide.
• Half of people with glaucoma are not aware they have the condition.

When should you see a doctor?

Consult an ophthalmologist promptly if you notice:

• New floaters or flashes of light that appear suddenly, increase, and persist. Floaters warrant urgent care if accompanied by light flashes which signal retina damage.

• Purple haze, smoke or loss of clarity in central or peripheral vision, especially if it arises suddenly.

• Veil or curtain obstructing any part of vision, with straight edges or colored fringe. This may indicate a retinal detachment.

• Halos or rainbows around lights.

• Dark blurry patches or decreased vision after blinking.

• Difficulty differentiating colors like purple and blue.

Seek emergency care if purple vision occurs with:

• Sudden severe headache, eye pain, dizziness, muscle weakness or numbness.

• Nausea and vomiting.

• Head injury or trauma.

• Loss of coordination or balance.

Such neurological symptoms accompanying purple flashes can indicate a stroke, aneurysm, blood clot or seizure – critical conditions requiring rapid treatment.

Diagnostic tests

To determine the cause of purple vision an ophthalmologist may conduct:

• Eye exam – Tests prescription, pupil reaction, peripheral vision and ocular motility. Examines cornea, lens, vitreous humor and retina for damage. Measures eye pressure.

• Visual field test – Measures central and peripheral vision, and detects any loss or blind spots.

• Optical coherence tomography (OCT) – This non-invasive retinal scan uses light waves to capture high-resolution cross-sectional images identifying damage.

• Fundus photography – Specialized camera photographs interior surface of the eye showing retina, optic disc, macula and posterior pole to spot abnormalities.

• Ocular angiography – Sodium fluorescein dye injected into the arm travels to the eye, makes blood vessels visible to highlight leakage indicating damage.

• Electroretinography – Tests retina‘s electrical response to light exposure to evaluate retinal function.

• Color vision test – Identifies inability to detect certain colors, especially red or green in case of color blindness.

• Blood and genetic tests – Complete blood count, platelet levels, clotting time, sickle cell screening and genetic markers of clotting disorders.

Beyond an eye exam, the ophthalmologist may recommend neuroimaging tests like an MRI to check causes like stroke, aneurysm or brain tumor for purple vision accompanied by headache or neurological deficits.

When is purple vision normal?

While chronic purple flashes warrant medical care, brief sparks of purple or violet are usually nothing to worry about when:

• Momentary afterimages from staring at bright lights, screens or lasers. Looking at the sun should always be avoided, though.

• Very transient purple dots or lines that come and go in seconds, especially if blinking makes them disappear. These could just be harmless photopsia.

• Occurring when waking up as retinal cells fire on gaining consciousness.

• During meditation as pineal stimulation causes shades of lavender, purple and indigo. However, very frequent purple flashes in meditation may need evaluation.

• Following strenuous coughing or sneezing which generates vitreous traction on the retina.

• In the periphery due to normal retinal lattice degeneration.

• Floaters that drift away when trying to focus on them. Benign floaters usually appear and disappear rather than being continuous.

• Unassociated with any other symptoms like pain or vision changes.

• Resolves quickly – short lasting purple streaks upon shutting eyes after exposure to bright sunlight is normal.

Tips for relief and prevention

If purple flashes persist and worry you, it‘s advisable to see an ophthalmologist. But for managing transient violet sparks or afterimages try:

• Avoiding screens when seeing more floaters or purple flashes to give eye muscles adequate rest.

• Using lubricating eyedrops as dryness exacerbates debris and inflammation. But avoid redness-relieving drops that constrict blood vessels.

• Wearing sunglasses outdoors and limiting exposure to harsh direct light.

• Taking hourly short breaks during lengthy digital device use.

• Ensuring prescription glasses or contacts are clean and fitted properly. Updates may be needed.

• Treating any underlying health factors like controlling high blood pressure and blood sugar levels.

• Consuming a diet rich in greens, fatty fish, nuts and antioxidants like lutein and zeaxanthin to support eye health.

• Reducing alcohol intake which causes vasodilation and photoreceptor damage when excessive.

• Quitting smoking and recreational drug use that impede ocular blood flow.

• Doing eye exercises like gentle palming, massaging around eye sockets, focusing on finger movement and consciously blinking.

• Relieving anxiety and stress through yoga, mindfulness, therapy and other relaxation techniques.

• Getting 7-9 hours of sleep nightly. Insomnia strains the eyes.

• Seeing an optometrist annually for a comprehensive eye exam to evaluate prescription, eye pressure, and catch any developing problems early.

What causes purple vision in kids?

While adults should schedule an urgent eye exam for new onset purple flashes, children complaining of purple vision generally merit less concern.

According to Pediatric Ophthalmologist Dr. Barry Kran, the most common causes of purple flashes or halos in children are:

• Active imagination – Some kids just have a penchant for the color purple.

• Fatigue – General tiredness or eyestrain from sustained focus on books or screens can cause harmless afterimages.

• Migraine – Children between 5-15 years old can develop migraines with visual auras.

• Medications – Antibiotics or antihistamines may rarely cause temporary color perception changes as a side effect.

• Head injury – Minor knocks on the head can jar the retina.

• Eye rubbing – Excessive rubbing can stimulate photoreceptor cells.

Unless accompanying other symptoms, or occurring very frequently, purple visions in children are unlikely to signal any eye or brain condition warranting intervention beyond rest and eye drops.

The bottom line

While momentary purple flashes are usually nothing concerning,persistent purple fog, spots or vision loss should be evaluated urgently by an ophthalmologist. Purple haze or tint continuous over hours or days suggests blood, vascular or nerve damage requiring prompt treatment. Seek emergency care for purple vision accompanied by severe headache, numbness, dizziness or trauma. With myriad factors implicating the complex visual system, don’t take violet visions lightly. Consult an eye specialist for diagnosis and peace of mind.