What is an Eye Exam?
- An eye exam is a series of tests performed by an ophthalmologist (commonly known as the eye doctor or eye surgeon), an optometrist or an orthoptist to assess the functioning of the eyes and associated structures.
- An eye exam involves checking the eyes for gross abnormalities such as a strabismus or squint and ptosis, a complicated name for droopy eyelid, followed by a more detailed evaluation of vision, functioning of the pupils and extraocular muscles, visual field estimation, measuring pressure within the eyeball and ophthalmoscopic examination after dilating your pupils. A complete eye exam can detect various types of eye disorders and deficiencies in vision.
Everyone needs regular eye exams, particularly if you have a family member with visual problems!Adults should visit an eye doctor at least every two years and annually after age 60. Children need their vision checked at 6 months, 3 years, and before first grade.
What to expect during an Eye Exam?
- An eye exam is a battery of tests to evaluate various eye functions and involves the use of various equipment and charts to assist the examiner in diagnosing your eye problem. A thorough eye exam can take anywhere from half an hour to an hour of your time.
- The examiner might initially examine your eyes, pupil size, pupil reaction, and the surrounding area with a torch light. Subsequently, he might ask you to read various charts to evaluate your near, distant and colour vision. If any abnormality is detected, he further moves on to use various lenses to quantitate the refractive power of your eye and suggest contact lenses and corrective glasses. He might ask you to look in various directions or look through some peculiar equipment to evaluate your visual fields and your eye muscles. A slit lamp examination helps the eye surgeon to find any abnormalities in the cornea, lens and anterior chamber of the eye.
Evaluation of glaucoma is through a special test called tonometry which measures the pressure within the eyeball.
- The eye doctor might consider using some drops to dilate your pupils for examining your retina, the back of your eye that helps you see. It can help detect defects in the retina such as macular degeneration or diabetic retinopathy. This procedure can cause some discomfort and difficulty in seeing near objects for a few hours, until the effect of the medication wears off. This is however needed for proper evaluation of your retina and is a safe procedure.
What does your eye doctor look for during an Eye Exam?
Every test during an eye exam helps the eye doctor to evaluate different aspects of your vision or eye health. The eye surgeon meticulously looks for the following during an eye exam:
- Gross examination: strabismus or squint eye, ptosis or droopy eyelids, infections of the eyelids, conjunctiva or cornea, swellings of the eyelids such as stye or traumatic damage to the eye. He checks the pupillary function using a torch light to rule out Horner’s syndrome or Argyll Robertson pupil.
- Slit-lamp examination: This helps the eye surgeon analyse your cornea, anterior chamber of the eye and your lens. It can detect corneal abrasions, corneal ulcer, infection and inflammation in the anterior chamber of the eye and various types of cataracts.
- Tonometry: By this procedure, an eye doctor knows the pressure within your eyeball helping him to diagnose glaucoma, wherein intraocular pressures are extremely high.
- Visual acuity: Defects in near vision, distant vision, colour vision, and assessment for the need of corrective lenses such as contact lenses, glasses or surgery. It can detect near-sightedness, far-sightedness, presbyopia, amblyopia and colour vision.
- Visual fields: Visual fields are analysed by asking you to look into an instrument and identify location and type of objects on a screen. This helps detect some blind spots in the retina and your visual field integrity.
- Ophthalmoscopy: When an eye surgeon looks into your retina through an ophthalmoscope, he can distinguish a normal retina from diseased retina like macular degeneration, diabetic retinopathy, maculopathy, and retinal detachment. He can also suggest your corrective lens using this method.
- Ultrasound biomicroscopy: This helps to detect your eye dimensions and various corrective lenses required prior to cataract surgery.
- Specialized tests include keratometry, gonioscopy, ocular imaging, ocular computed tomography among various others.
An eye exam thus evaluates various aspects of your eye function and detects any developing eye disease. A regular eye exam potentially detects treatable blinding eye conditions, eye manifestations of other diseases or even helps detect and monitor tumours or other anomalies within the brain.