Straight Outta PVC

WHAT IS an auto refraction?

An autorefractor is an instrument that can give an estimate of a patient’s current glasses prescription. This test can only be run once the patient has removed any glasses or contact lenses that they normally wear. Patients are asked to focus on an image while the OA maneuvers the instrument around to each eye, and once it is in the correct place, the machine automatically completes the measurement. This measurement is an objective (not requiring a patient response) measurement of the patient’s prescription, in contrast to the subjective measurement of their prescription obtained when the doctor refracts a patient using the phoropter. It is fairly common that a patient might find the objective measurement blurry, which is why the doctor uses the objective measurement only as a starting place, then refines it through subjective testing until arriving at the patient’s new, finalized glasses prescription. Because the autorefractor doesn’t require patient response, it can be extra helpful in eye exams for small children or for people with special needs who may have trouble sitting calmly during an extended exam or verbally describing their vision problems.

Side Note: in addition to giving an estimate of a patient’s glasses prescription, the autorefractor also completes keratometry (a measurement of the curvature of the cornea) which is useful for fitting contact lenses. The instrument can be adjusted to complete the autorefraction, keratometry, or both. These options can be cycled through using the button on the upper left corner of the screen.

HOW TO Complete an auto refraction

To turn on/off: flip the switch on the right side of the instrument (this is done at the beginning of the day and then left on until close).

1. Have the patient remove glasses (if they are wearing contacts then the test will have to be postponed)

2. Have the patient place chin in the center of the chinrest and rest forehead against the head rest; adjust the chinrest and height of the table as needed. Instruct the patient to focus on the house/barn at the end of the long white fence (in Lewis Center they will be focusing on a hot-air balloon).

3. Center the instrument in front of the patient’s right eye. Rotate the stick right to raise the instrument and left to lower the instrument as needed.

4. Slowly move the instrument forward or backward to bring the patient’s eye roughly into focus. Once you are close, the screen will start to give you prompts, << O >> move out; >> O <<.move in).

5. Once focused, the instrument will automatically take 3 measurements.

6. Move to test the left eye, repeat steps 3-5.

7. The instrument will automatically print the results when 3 measurements per eye are recorded (in Lewis Center you will need to press the print button on the bottom left of the screen to get the reading to record onto the card).

8. Wipe headrest with alcohol

How to record an auto refraction into the chart

After obtaining readings from each eye, the auto refractor will print out the test results (see example below). The printout should have a measurement of the patient’s glasses prescription in bold for each eye as well as a PD (pupillary distance) reading. If keratometry was selected to be completed, keratometry readings will also be at the bottom of the print out.

To enter this information into the patient record, open up the chart for the day and go to the WorkUp tab. On this tab, in the lower right corner, you will find the refraction/visual analysis table. The auto refraction will go in this table. To add an entry, click on the three dot ellipsis in the upper left corner of the table and select ADD.

This will open up a new window where the measurement of the patient’s glasses prescription for each eye as well as the PD measurement can be entered. Under Type at the bottom of the window, enter Autorefractor. Once everything has been entered, click the save button in the upper right corner of the window.

The autorefraction entry is then added to the table.

Here is a video that shows how to enter an autorefraction entry.

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