What To Expect From An Eye Exam
A full eye exam has many components.
We have a few tips for you to prepare for your eye exam. Be prepared to give a full medical history. Drs. Switch and Rasansky are medical doctors and, although it may not be intuitive, many medical conditions including Diabetes, Hypertension, Autoimmune Disease as well as many others affect the eyes.
Make sure to bring in your current eyeglasses and a list of any medications you currently take.
A full eye exam requires the patient’s pupils to be dilated with eye drops. This allows Drs. Switch and Rasansky to evaluate your entire eye. Dilating eye drops may cause your vision to be blurry for several hours. This affects some people more than others, and although many people feel fine driving after their exam, so me may be more comfortable bringing along a family member or friend who can drive you home.
- Visual Acuity (VA). A subjective assessment of your vision is called a Visual Acuity test, or VA. Vision is tested using a standardized eye chart at a specific distance and lighting. The Visual Acuity is recorded as a fraction of the distance over the letter size. Normal vision is recorded as 20/20. Please see the section on Normal vision for further information.
- The External Slit Lamp Exam. This portion of the exam involves the structures surrounding the eye and the front portion of the eyeball. The following structures are evaluated: The eyelids, lashes, conjunctiva, iris, cornea, lens and anterior chamber. This exam takes place using a slit lamp biomicrosope and may be supplemented by a Gonioscopy lens if glaucoma is suspected.
- Confrontational Visual Fields. This test is used to detect evaluate the patients peripheral vision. Defects in the visual fields may signal the need for further evaluation for conditions such as glaucoma, retinal detachment and or possible neurological problems.
- Pupil Reflex Tests. This test uses a small light to test the reflex of the pupil and its ability to constrict and dilate. Abnormalities of this test may signal a problem with the optic nerve or brain.
- Ocular Motor Test. In this test, the function of each of the seven eye muscles is tested its ability to conscript and work simultaneously with its fellow muscles in the other eye. Abnormal results may indicate a cranial nerve problem or other pathology of the muscle itself.
- Rotations, Versions, Divergence and Convergence. In this test, the eye’s ability to track a moving object will be tests vertically, horizontally and rotationally. Each eye is tested individually and then together. Your eyes will be tested for proper alignment and ability to focus on a target at distance and near.
- Depth perception and Color Vision. Tests the analysis of depth perception and color perception is often tested on children. This test is not commonly tested on adults unless evaluating for specific problems (medication toxicity) or for specific career fields such as pilots.
- Ophthalmoscopy. This test allows the examiner to evaluate the internal structures of the eye. This is the only non-invasive test that allows a physician to see the inside of the human body and evaluate the vascular structures and vessels. This test may serve as to detect early disease damage from diabetes, hypertension and other disease affecting the whole body. This test is preformed using a direct and indirect ophthalmoscope. Both use a light source and sets of magnification lenses to view the back of the eye through the dilated (open) pupil. For this test, the patient should be dilated using eye drops. By dilating the pupil, the physician is able to see the full retina, which cannot be seen through an undilated pupil.
- Tonometry. This test is used as the initial screening for glaucoma. The pressure of the eye is tested using one of two instruments. Both require the instillation of a numbing eye drop. Dr. Switch uses instruments that do not utilize the “air puff” and offer superior accuracy. Elevated eye pressure is a sign of Glaucoma.
- Keratometry and Topography. The curvature of the cornea is measured using a simple automated test. Irregularity of the corneal curvature is known as Astigmatism.
- Auto-refractometry and Subjective Refraction. Refraction is a measurement of the eyes ability to focus light. The first test is an automated computerized estimate of your glasses prescription. The subjective refraction allows your glasses prescription to be refined using your input. The examiner will flash different lenses in front of your eye and you will be asked to pick between the choices until you determine which is the most clear.
- IOL Master Measurements. This test is used for patients who are considering cataract surgery. The results of this test give the surgeon the specific measurements of the eye. Using these measurements, the surgeon is able to determine the appropriate lens power for cataract surgery.