The eyes have a lot to say about overall health. Don’t ignore these irritating issues

Some common vision problems are nothing to worry about, usually related to aging and normal prescription changes, but the sudden onset of symptoms like blurred or double vision are cause for concern.

Most changes in vision or the look of the eye, whether it’s seeing spots or redness, should prompt a visit to the eye doctor.

Besides the fact we only get one set of eyes, many vision problems are linked to more systemic or serious illnesses. In 2014, 240,000 patients were diagnosed with diabetes in an eye doctor’s office, says Dr. Andrea Thau, president-elect of American Optometric Association.

“The optic nerve is an extension of the brain,” says Thau, a Manhattan-based developmental optometrist and associate clinical professor at the SUNY College of Optometry. “The eye is the only part of the body that you can actually see someone’s arteries and veins without having to cut them open, which is one of the reasons we can find diabetes, hypertension or an impending stroke.”

Optometrists provide the vast majority of eye care in the United States and often help diagnose and manage high blood pressure, autoimmune diseases, stroke and even cancer, adds Dr. Wil McGriff, an assistant professor at Southern College of Optometry who sees patients at its clinic in Memphis, Tenn.

“We’re not just prescribing eyeglasses,” he says. “We can help people identify problems before they become severe or life-altering.”

Here’s a brief look at the seven common vision problems and what they could mean. Your doctor of optometry should evaluate any of these symptoms during a comprehensive eye exam.

1. Blurred Vision

Blurred vision can indicate a number of different eye conditions or diseases ranging from normal to severe. Uncorrected farsightedness (hyperopia), nearsightedness (myopia) or astigmatism can cause blurred vision. It’s usually related to a refractive problem and can be corrected with eyeglasses or surgery, McGriff says.

Blurred vision also may be related to inflammation inside the eye due to infections, injuries or auto-immune disease. It is a key symptom of macular degeneration or cataracts. Multiple sclerosis, Crohn’s disease, uncontrolled diabetes or aneurysms are a few of the many systemic diseases associated with blurred vision.

Sudden onset blurred vision could be a retinal detachment, which requires surgical correction, and needs to be checked out by an optometrist.

“In general, the sudden onset of new visual symptoms warrants a prompt eye examine,” Thau says. “The list is very long and extensive of the things that can cause blurred vision.”

2. Double Vision

If the symptoms are temporary, double vision may be brought on by eye strain, fatigue or alcohol. But sudden onset double vision could be a symptom of stroke, head injury, brain tumor, brain swelling or brain aneurysm.

“Many people have eye coordination problems that can result in double vision at times,” Thau says.

McGriff agrees double vision in adults that comes on suddenly should be evaluated right away.

“If it’s true double vision where you see two images, it’s more of a serious concern and something we take very serious,” he says. “It could be associated with diabetes or a stroke or cataracts. You really can’t tell unless you have an eye exam.”

3. Cloudy Vision

Cloudy vision is usually the result of cataracts, a cloudy or opaque area in the normally clear lens of the eye. Swelling of the cornea due to corneal disease or contact lens complications can also cause it, Thau says.

If the eye becomes cloudy over the course of the day, or it comes and goes, it could be related to dry eye, McGriff says.

“If it’s more persistent, cataracts are a more common cause, and we recommend they have cataract surgery to improve that,” he says.

4. Night Blindness

Night blindness is a common complaint of older drivers, and cataracts, diabetic retinopathy, lack of anti-reflective coating on glasses or other eye conditions can exacerbate difficulty seeing at night. Retinitis pigmentosa is a progressive, genetic eye disease that causes retinal degeneration and decreased night vision.

The most common cause of poor night vision is nearsightedness that is worse at night, according to McGriff.

“The nearsightedness can be addressed with glasses or specific eye drops,” he says. “The more persistent forms of night blindness are genetically determined diseases, which usually require changes in driving behavior and are associated with vision loss.”

It may be as simple as a new eyeglass prescription, but it’s best to talk to your optometrist about your concerns.

5. Tunnel Vision

Some episodes of tunnel vision are shortlived or temporary and may be related to low blood pressure, head injury or migraines, McGriff says.

More often, tunnel vision is associated with diseases of the retina and optic nerve like glaucoma, an irreversible eye disease in which the nerve fibers in the optic nerve become damaged. This can result in vision loss, especially peripheral vision, and occurs due to an increase in intra-ocular pressure.

“Glaucoma is fairly common in the population, but other retinal problems are much less common and rare,” McGriff says. “Those require medical management by an eye doctor and may ultimately require treatment by a low-vision specialist.”

Early signs of glaucoma are usually not noticeable, and early detection and treatment of glaucoma are critical to prevent vision loss, Thau says. Retinitis pigmentosa, an inherited retinal disease, also may cause tunnel vision.

6. Floaters/Spots

If you see a large number of floaters and spots, especially if flashes of light accompany them, you should seek medical attention immediately. It could be a sign of a retinal detachment, which occurs when the light sensing part of the eye pulls away from the underlying support structures to which it is attached.

“This causes symptoms of flashes and floaters and permanent vision loss if it’s not repaired,” McGriff says. “Those are big red flags for eye doctors. Thankfully, it’s relatively uncommon, but it requires pretty rapid surgical repair.”

Floaters and spots appear when tiny pieces of the eye’s gel-like vitreous break loose within the inner back portion of the eye, Thau says. New floaters require a dilated eye examination to rule out a retinal detachment.

For most people, while annoying, floaters do not result in a retinal detachment. Still, it’s better to visit an optometrist and have them checked out.

7. Red Eyes

Red eyes may be more common, but it doesn’t mean it’s a symptom to ignore. Red eyes can have a number of underlying causes, from a minor scratch or abrasion to a reaction to chemicals or an eye infection.

Bacterial infection, viruses or allergies can cause conjunctivitis, an inflammation or infection of the conjunctiva, the thin transparent layer of tissue that lines the inner surface of the eyelid and covers the white part of the eye. An accumulation of blood underneath the conjunctiva can cause the whites of the eyes to appear red. Corneal ulcers, a serious eye infection that affects the cornea, also can cause red eyes, Thau says.

Red eyes may be related to dry eyes or environmental irritants like smoke, dust, dry air or even fatigue, McGriff adds. He says some over-the-counter products such as Visine and Clear Eyes can aggravate symptoms and make the red eye worse.

If it’s due to dry eye, artificial tears (brands like Thera Tears, Systane and GenTeal) can help to lubricate the eye, but a professional should evaluate prolonged or persistent symptoms.