Rather than spending inordinate amounts of time doing strictly subjective procedures, most refractionists utilize objective (what we see……something that does not require a response from the patient) testing to streamline the process considerably. In today’s high tech world, most offices now use auto refractors, which are objective machines, but we will describe the most widely used manual objective procedure, the neutralization technique using a retinoscope. I hope you find the material interesting and of use in the office.

Objective Procedures
Refraction is also performed using a variety of objective tests. As mentioned, today, many offices utilize an auto refractor, which can provide a fairly accurate estimation of the refractive error. While an auto refractor is a great machine, we will focus our attention to a much simpler device, the streak retinoscope. The streak retinoscope is a device invented by Jack Copeland around 1920 (Corboy, 1989). While others had defined streak retinoscopy, Copeland’s scope is the basis for all others today.

In streak retinoscopy, the refractionist sweeps across the pupil with the scope, watching the movement of the streak of light from the scope in the eye. If the streak appears to be moving against the direction the scope is moving, minus lenses are employed. If the streak moves with the observer, plus is required. If there is no apparent motion, neutrality has been reached. The streak will vary in different meridians if astigmatism is present. This procedure sounds simple here, and it basically is, but it is difficult to master. It takes time and practice to become proficient. It is also important to remember that when one is scoping, the eye is “chained” to the scope. The refractionist is only about 67 centimeters away from the eye. The focal point measured at that point is on the scope. An extra –1.50 diopters must be added to the retinoscopy finding to move the focal plane into infinity, or the retinoscopy lens on the phoropter may be employed. Again, this topic is difficult to present, and must be seen and done to fully understand.
Once the objective procedure is completed, the subjective refinement procedures described earlier are employed.

The significance of objective procedures is evident with illiterate patients, children, or others who can’t subjectively respond. It is also much faster than a strictly subjective procedure.

Reading Adds
To find the correct reading add is a difficult task. Most refraction errors come from improper add power. We will not attempt to discuss a great deal of theory here, but you should know that a patient can comfortably utilize ½ of their available amplitude of accommodation (the amplitude of accommodation is the reciprocal of the near point). Amplitude diminishes with age. For example, researchers claim we have, at age 10, between 11 and 14 diopters of accommodative amplitude; at age 40, it is between 4.5 and 5.5 (Borish, Vol. 1, 1970, pp. 169-170). It takes +2.50 diopters of accommodation to focus at 16 inches, which is the normal reading distance. If we only have approximately +5.00 available, then it is easy to see why we need bifocals around age 40. Unfortunately, all people are not the same. Some need a +1.00 add at 40, while others prefer a +1.25.

A fairly simple, but effective, way to determine the correct add power is to utilize an Egger’s Chart for near. A rule of thumb that works well states that at age 40, a +1.00 - +1.25 add will be required. Add +0.25 for every 5 years of age. For example, if at age 40, a +1.00 add is required, a +1.25 would be expected at age 45.

Always test subjectively. Ask patients about their reading requirements. Some like to read at 20 inches, others at 14. Computer use should be discussed, and an approximation of the computer screen distance should be formulated. Using the near point rod on the phoropter it is relatively simple to check the range through the reading add. Some compromises may need to be made, or specialty glasses for computer use required. Communication is extremely important in refraction. Discussing the patient’s needs and expectations is the most important thing the beginning refractionist must learn.

Additional Testing Procedures
There are a multitude of functional tests that would be performed at the end of the basic refraction that are beyond the scope of this article. Tests for phorias and tropias may be the topic of the next article on refraction.

Discussions
Refraction is an exciting adjunct to Opticianry. As you can see, it is something you can effectively do with the proper training. There are job opportunities available for Opticians trained in refraction, or Ophthalmic Opticians, as they are known in Europe. I encourage you to take a course in refraction if you have not; and if you have, keep up to date with continuing education seminars. I encourage you to get involved, even if you don’t want to refract. I guarantee you will learn a great deal!

One concern many have about learning refraction is the steep political curve Opticians will have to face to actively utilize this knowledge. In reality, that is far from the truth. Many offices are looking for trained refractionists to practice with the Ophthalmologist or Optometrist. Even beyond that, I have never had a student leave a class that did not become a better Optician based on what they had learned. 
If you can truly understand how those numbers we call a prescription are developed, then you can more effectively assist patients who come back with problems or concerns, and you will save both the OD/MD and patient time and energy. You can help them, and really know what you are doing. Many Opticians claim to be great problem solvers, but in reality only take a stab in the dark. To really know, you must understand the process of refraction.

The Future
People regularly ask if I feel Opticians will ever gain the “right” to refract. Quite frankly, I do not see it as a right, but a skill set, and I believe in the right environment, Opticians can and do refract today, and very successfully I might add. Will we ever gain a license to do so independently? Until we make some major changes, I can emphatically say NO! We must mandate a formal education and additional clinical training prior to undertaking that goal. We must learn more about anatomy and physiology, and believe it or not, optics. But we can, in the right setting now, work with MDs and ODs as mid-level practitioners like Nurse Practitioners and Physician Assistants. We can make their lives easier, and provide our full scope of dispensing services at the same time. 

Conclusion
I hope you have found this article of interest. I am passionate about improving the lives of Opticians all across America, and believe strongly our best days are ahead of us, but only if we all want them to be. It is imperative that we move towards new goals and reach greater heights, and then we will see our profession blossom as never before.

References on request

Warren G. McDonald, PhD
Professor of Health Administration
Reeves School of Business / Methodist University