Health problems you didn’t know could be detected by an eye exam (e.g. cancer)

Fact checked by Nick BlackmerFact checked by Nick Blackmer

Key findings

• Annual eye examinations can detect eye diseases and vision problems.

• Your eyes and vision may be affected by other health problems.

• An eye exam can also tell you about other health problems that may be present.

An annual examination by an optician helps Eye of course, but the appointment involves much more than just checking your vision. During an eye exam, the doctor examines various parts of your eyes, which can also provide clues about the health of the rest of your body.

“A comprehensive medical eye exam can often give us clues as to what is going on in a person’s body,” Dr. Mina Massaro-Giordano, co-director of the Penn Dry Eye & Ocular Surface Center and professor of clinical ophthalmology at the University of Pennsylvania, told Verywell.

What else can an eye exam tell you besides your eye health? Here’s what experts think.

Related: What to expect during a routine eye exam

Health problems that can be detected through eye exams and that have nothing to do with the eyes

Eye exams not only help identify problems with your eye health, but they can also uncover a number of health problems. “Sometimes people don’t know they have these conditions,” Massaro-Giordano said.

Here are just some of the diseases and conditions that can be detected during an eye examination:

• Aneurysm

• Brain tumors

• Cancer of the blood, tissue or skin

• diabetes

• Heart disease

• High blood pressure

• High cholesterol

• Lupus

• Lyme disease

• multiple sclerosis

• Rheumatoid arthritis

• Sexually transmitted infections

• stroke

• Thyroid disease

• Vascular disease

“Parts of the eyes – the retina and optic nerve – are a direct extension of the central nervous system and the only place in the body where blood vessels can be seen without breaking the skin,” Ann Morrison, OD, PhD, assistant professor of optometry at Ohio State University College of Optometry, told Verywell. “Because ophthalmologists can see these structures directly, diseases affecting the central nervous system or vascular system are sometimes first detected in the eyes.”

“Diabetes is a pretty common problem that we see,” Michelle Holmes, OD, an optometrist at the Pacific Neuroscience Institute in Santa Monica, California, told Verywell, adding that high blood pressure, high cholesterol and “anything related to cardiovascular disease” can also have signs that can be detected during an eye exam.

Even in patients who already know they have a particular disease, an eye exam can provide valuable insight into how serious the disease or disorder is, Holmes said. “For example, if I see signs of diabetes in the eye, that may mean the disease may not be well controlled,” she said.

What happens during an eye examination?

“To prepare for an eye exam, you don’t need to do anything except bring your glasses (if you wear glasses) and a list of all your medications,” Quiros said.

Every practice is different, but in general you can expect a similar process wherever you go for an eye exam.

“First, an ophthalmologist will review your medical history and evaluate any eye or vision symptoms you may have,” Morrison said.

The doctor will then perform a series of tests. Peter Quiros, a neuro-ophthalmologist at the UCLA Stein Eye Institute, told Verywell that the tests may check the following aspects of your vision:

• Visual acuity (testing your ability to read an eye chart from a distance and up close)

• Refraction (checking whether you need a corrective lens)

• Peripheral vision (seeing colors, movements and shapes outside your central vision)

• Intraocular pressure

• Pupils (to look for signs of neurological disease)

• Eye movement and alignment (to check for double vision)

• Positioning of the eyelids

• Front of the eye

• Lens in the eye

• Optic nerve (transmits visual information to the brain)

• Retina (the light-sensitive tissue layer at the back of the eye)

“The doctor will then check your glasses and/or contact lens prescription – this is the part of the exam that addresses the question ‘Which is better, 1 or 2?'” Morrison said.

During the exam, you may also see some tools, including an eye chart, an autorefractometer (a device that measures how light passes through the eye), a penlight, and a slit lamp (a magnifying microscope with a bright light).

Your doctor may need to dilate your pupils during the exam, and the effects of the drops may last for several hours. In that case, “you should probably have someone with you who can drive you home,” Zarbin said. If that’s not an option, you may need to stay in your doctor’s waiting room until your eyes return to normal.

Quiros recommends that you bring sunglasses to your appointment, as dilation can make your pupils sensitive to light.

Related: What is an eye exam for diabetes

How often do you need an eye exam?

The frequency of an eye exam “depends on your age and overall health,” Marco Zarbin, MD, PhD, chief of the department of ophthalmology and visual sciences at Rutgers New Jersey Medical School, told Verywell. The American Academy of Ophthalmology (AAO) recommends the following:

• Ages 20–39: One eye examination in the twenties and two examinations in the thirties

• Age 40–54: An eye examination at age 40, with follow-up examinations every two to four years

• Age 55–64: Examinations every one to three years

• From age 65: examinations every one to two years

However, age isn’t the only factor – your overall health also determines how often you need to have your eyes checked. People with vision problems or underlying conditions like diabetes may need to be checked more often, according to Zarbin.

Related topics: What an eye exam can reveal

“Regular eye exams are critical to detecting problems early and maintaining eye health,” Holmes said. But it’s not always easy to get eye care if you don’t have insurance or your plan doesn’t cover vision care.

If you need an eye exam but don’t have insurance, Quiros recommends learning about EyeCare America, an AAO-sponsored program that helps people access eye care and resources.

What this means for you

Regular eye exams aren’t just helpful for checking your vision—they can also detect signs of other health problems. The recommended frequency of the exam depends on your age and overall health. If you’re worried about paying because you don’t have health insurance for your eyes, there are resources that can help.

Read more: What is the difference between an optometrist and an ophthalmologist?

Read the original article on Verywell Health.