The medical assistant's role in eye examinations

As a medical assistant, you may be involved in assisting with the examination, diagnostic procedures, and treatments. Having an understanding of what will be required of you during those processes will help you provide the best possible care for your patients and be the best assistant for your provider. The following sections describe your role.

Assisting with the examination and diagnostic procedures of the eye

In a primary care department, the examination of the eye is a screening examination. If the provider suspects that there may be an issue with a patient’s eyes, the patient will likely be sent to an ophthalmologist for further evaluation and treatment. There are several screening diagnostic procedures that a medical assistant can administer when directed to do so by the provider. The following sections discuss how the medical assistant is involved in the examination and diagnostic procedures of the eye.

Assisting with the examination of the eye

A complete examination of the eye is technical and requires expensive equipment and the expertise of an ophthalmologist or optometrist. However, a primary care provider performs some basic examinations and treatments of the eye. The ophthalmoscope is used to examine the interior of the eye. It projects a bright, narrow beam of light through the lens and illuminates the interior parts of the eye and retina. It is helpful for detecting disorders of the eyes and certain systemic disorders, such as capillary changes that occur with diabetes mellitus.

The eyelids are examined for edema, which may be the result of nephrosis, heart failure, allergy, or thyroid deficiency. Blepharoptosis, also called ptosis, is drooping of the upper eyelid that can be caused by a disorder of the third cranial nerve, muscular weakness as seen in muscular dystrophy, or myasthenia gravis.

The pupils of the eyes are normally round and equal. Normal pupils constrict rapidly in response to light. This is demonstrated by shining a bright, pinpoint light into one eye from the side of the patient’s head. The pupil of an illuminated eye constricts, and the pupil of the other eye constricts equally. This test is called light and accommodation (L&A). The eyes of an older patient do not accommodate as well as those of a younger person. Each eye is checked this way. The patient is then asked to look at the provider’s finger as it is moved directly toward the patient’s nose to check for eye coordination. If the pupils are equal and round, respond normally to light, and adjust and focus on objects at different distances in a reasonable length of time, the provider charts the acronym PERRLA (which stands for “pupils, equal, round, reactive to, light [and], accommodation”).

PERRLA P Pupils E Equal R Round R Reactive to L Light (and) A Accommodation

Special techniques used in the ophthalmologist’s office include examinations performed with a slit lamp biomicroscope. This device is used to view fine details in the anterior segments of the eye. It may be used to view a foreign body because it gives a well-illuminated and highly magnified view of the area. For this examination, the provider first orders the administration of a mydriatic eye A patient with exophthalmia (abnormal protrusion of the eye, possibly resulting from an overactive thyroid or a tumor behind the eyeball) is checked with an exophthalmometer. This instrument measures how far the eye protrudes beyond the edge of the eye socket and helps determine the level of tissue swelling and enlargement behind the eye.

Distance visual acuity

Determining distance visual acuity frequently is part of a complete physical examination. It is widely used in schools and industry and is the best single test available for vision screening. Many cases of myopia, astigmatism, and hyperopia have been detected with this routine test. The chart most commonly used is the Snellen alphabetical chart. This chart displays various letters of the alphabet, which the patient must identify in ever smaller font sizes. Patients with limited knowledge of the English alphabet can be tested with the E chart. In addition, a chart that uses pictures and symbols is available. This chart is used for young children or individuals who do not know the alphabet. To avoid patient confusion over the E chart or the symbol chart, the medical assistant should review the charts with patients first to make sure they know how to demonstrate the E visualized or the meaning of each picture or symbol. The symbol on the top line of the chart can be read at 200 feet by people with normal vision. In each of the succeeding rows, from the top down, the size of the symbols is reduced so that a person with normal vision can see them at distances of 100, 70, 50, 40, 30, and 20 feet consecutively.

The patient must not be allowed to study the chart before taking the test. The room or hall should be long enough that the 20-foot distance can be marked off accurately and without interruptions from patient and staff traffic. The chart should be hung at the patient’s eye level and illuminated with maximum light, without glare on the chart. Most adults do not need the standard Snellen chart explained, but if the E chart is used, an explanation must be given as to how the E’s are to be read. The patient may point up or down or right or left toward the part of the letter that is open. If the E chart is to be used for a child, practice with an index card with a large E drawn on it before the child is tested. Turn the card in different directions to simulate the position of the “fingers” of the E on the chart and give children the opportunity to demonstrate the direction of the E fingers by pointing their own fingers in the same direction.

Because this is a gross screening of distance visual acuity, the eyes are typically tested with corrective lenses; therefore, the patient should not remove glasses or contact lenses unless the provider requests it. Indicate in the patient’s health record whether the assessment was done with or without corrective lenses. Record the results of each eye separately and as fractions. The numerator (top number) is the distance of the patient from the chart (always 20 feet), and the denominator (bottom number) is the lowest line read satisfactorily by the patient. For example, if the patient reads the 20 line at 20 feet, the fraction 20/20 is recorded for that eye. The last line the patient can read without squinting or straining and with no more than two mistakes is the line recorded in the patient’s record for that eye. The medical assistant should document the outcomes of the test, specifying the results for each eye and both eyes. The Joint Commission no longer recommends using medical abbreviations for the eyes and ears because they are frequently confused or misinterpreted; therefore, the medical assistant must now document right eye, left eye, and both eyes.