To preserve your vision and ensure eye health, get a comprehensive dilated eye exam on a regular schedule. Aside from eye health due to genetics or aging, regular eye exams can keep your eye care professional abreast of your other medical conditions and it’s a great precaution to take to ensure your medications aren’t affecting your eyes adversely. Eye exams are painless. During an exam, an ophthalmologist will examine your eyes to see if you have any issues — whether common or rare — while also examining for diseases of the eye. Some eye diseases do not have any early symptoms, so regular care is integral to avoid these conditions.

A dilated eye exam differs from a basic eye exam done when you seek glasses or contact lenses. The purpose of a comprehensive dilated eye exam is to catch any eye diseases while they’re still in the early stages, therefore protecting your eyesight in the long run.

A comprehensive dilated eye exam includes the following:

Visual Acuity Test—This is the test most people think of about the eye doctor. During it, the patient is asked to read an eye chart and the responses will measure how well you see at various distances. Depending on the outcome, this test leads to a measurement for eyeglasses.

Slit Lamp Exam–Using a specialized microscope, the ophthalmologist gains the opportunity to view the front and back of your eye under significant magnification. The purpose is to find any small or large issues on the eye’s surface.

Tonometry—Glaucoma may be detected using tonometry. This test measures eye pressure, and if eye pressure is high, that could signal glaucoma.

Dilation—Drops are squirted into the eye and work to dilate, or widen, the pupils. Once the pupils are dilated, the eye doctor is able to more easily see into the retina using a special magnifying lens. The retina exam will tell the eye doctor if there is any damage or other eye problems, such as diabetic or hypertensive retinopathy, retinal detachment, retinal diseases, or macular degeneration. The dilation also allows the eye doctor to cehck for optic nerve damage. Optic nerve damage happens when a person has glaucoma, multiple sclerosis, stroke, diabetes, or other neurological issues.

Additional tests could also be included in the exam, including:

Visual Field Test – Data collected from this test looks at peripheral (side) vision and your field of view. It tells your eye doctor if you have damage to your field of vision, including glaucoma, strokes, brain tumors and other neurologic conditions.

Fundus Photograpghy – The doctor takes a photo of your retina and/or optic nerve to compare to future exams, therefore evaluating for damage.

Ocular Ultrasound (B-scan) – If cataracts or blood are in the eye, this ultrasound could be used to see any microscopic or large retinal structural damages. It also helps the eye doctor see different types of masses or visualize and quantitate floaters.

Anterior Chamber Scans (ACS) – This type of ultrasound gives the eye doctor an understanding of your risk or likelihood for developing a painful and rapid form of glaucoma. It also helps the doctor see and evaluate iris tumors and irregularities.

Specular Microscopy – This is a photo taken of the innermost layer of your cornea. It helps your eye doctor determine any genetic or acquired diseases of the cornea. If you have cataracts, this photo allows the ophthalmologist to customize your cataract surgery, as well as let you understand the potential corneal risks. This step is integral for those who may be a medical candidate for LASIK or other laser vision correction surgeries.

External Photography – A photograph of the surface of your eye or eyelids to compare during follow-up exams and evaluating for ocular surface changes or eyelid conditions, such as pterygium, chalazion, stye, and tumors.

Scanning Laser Tomography – This rapid photograph uses colored lights that microscopically evaluates the structure of the optic nerve and/or retina. The eye doctor can determine any structural defects or swelling of your optic nerve and/or retina, and provides an opportunity for future appointment comparison. This photo is especially important when the eye doctor monitors for the progression of glaucoma, diabetic or hypertensive eye diseases and other retinal diseases.

Corneal Topography – This photo quickly maps any structural issues in the cornea created from corneal infection, genetic or acquired corneal diseases.

Axial Scan (A-scan) –  This is a measurement of the size of your eye. This helps the eye doctor understand which type and size of implant to surgically adhere during cataract surgery.

Color Vision Test – This test determines if a patient has issues with color vision due to genetic color blindness, optic nerve diseases, or medications taken for other issues. The eye doctor will ask you to look at a set of color plates and describe what you see.

Stereo Vision Test – Determines if a person has any deficits in their 3D vision. 3D vision issues are attributed to strabismus (crossed or turned eye), eye muscle conditions, or lazy eye.

Sensorymotor Test – When eyes are misaligned, this test is used to test the neurologic and motor skills to determine the causes and extent of misalignment.