Today’s automated subjective refraction systems build office efficiency by allowing delegation and providing the same—or better—data than a manual phoropter.
Over its nearly century-long career, the phoropter has been a symbol of eyecare practice. Indeed, the manifest refraction remains a mainstay of the care we provide, giving us valuable information about the neurological—as well as the optical—component of the visual system. Subjective refraction with the phoropter is, however, one of the least efficient parts of the modern eye examination.
Using automated devices to perform the manifest refraction can greatly streamline the refraction process, increase office throughput and efficiency, simplify data management, and facilitate integration with other diagnostic equipment and electronic health record (EHR) systems. Thoughtfully implemented, these automated subjective refraction devices can be an investment in the eyecare practice of the future.
The subjective refraction process has two parts: data collection and the analysis and decision making based on that data. The training and skill required to use a phoropter has for decades meant that a doctor had to do the data collection as well as the analysis. But automated subjective refraction technologies allow clinicians to speed up and delegate the data collection part of subjective refraction, leaving more time for decision making, patient counseling, and seeing additional patients.
Automated subjective refraction can do more for a practice than simply save time. Anecdotal reports and an increasing number of studies show that automated subjective refraction data is equivalent in accuracy and may be superior in reproducibility to manual subjective refraction. A nationwide, evidence-based study of 180 eyes (for 2013 publication) has documented a differential of less than 0.25 diopters in sphere and cylinder powers between automated and manual subjective refraction.
Reproducibility of results is important for practices in which multiple doctors may see a given patient, especially in the context of cataract or refractive surgery and optometric comanagement. The accuracy and reproducibility of subjective refraction data generated by automated instruments has motivated the US military and many large private refractive surgery centers around the world to embrace these instruments.
Automation also ensures transcription accuracy: by linking to a practice’s EHR system, subjective refraction data can be automatically collected and incorporated into a patient’s record. Once captured, this data is available to other connected instruments in the practice, as well as to the optician.
Some automated subjective refraction systems are combined alongside instruments like aberrometers, keratometers, and lensometers, which provide a wealth of information that can work synergistically with refraction data, creating a more complete and detailed picture of a patient’s vision.
Automated Subjective Refraction in Practice
Automated subjective refractors work on the same principle as traditional phoropters, using patient responses to hone in on the right sphere and cylinder correction for each eye. Some semi-automated subjective refractors are designed to work in a standard 20-foot exam lane; while other systems economize on space and substitute a virtual visual acuity chart. The Marco TRS-5100 is an example of the former system, providing, push-button control of a chart projector as well as the lenses (Figure 1). The Epic-5100 (Marco), on the other hand positions the patient before a table-top device, occupying far less space (Figure 2).
Patients typically begin with either an autorefraction or wavefront aberrometer reading, providing a clear starting point for the subjective refraction. The Epic system can directly incorporate data from an autorefractor, aberrometer, or combination device (eg, the Marco OPD-Scan III). The Epic system also allows clinicians to review wavefront aberrometry data in the context of the manifest refraction, offering the ability to evaluate the impact of higher-order aberrations on the spherocylindrical prescription.
While the physical interaction may change little for patients, the examiner’s questions typically come more quickly with automated subjective refractors, and the comparisons to be made between lenses are fewer. Beginning from autorefractor data, the examiner usually needs only to refine the results with patient input. Fewer “Which is better?” questions can also mean a better patient experience.
Getting Used to Automation
The fundamental similarities between manual and automated phoropters make adaptation to automated devices relatively easy. The systems typically allow clinicians to pre-select certain parameters, such as which tests are to be run, the order in which they are run, and preferred ranges (eg, cylinder refinements in 0.25 D rather than 0.5 D).
I personally became convinced of the technology’s value when we began to compare refractions under photopic and scotopic conditions, using the Epic system. Our practice serves many older patients, and compromised night vision is one of their most common complaints. Now, we are able to measure and address differences in refraction between bright and low-light conditions; and in many cases, when we show patients the difference between their day and night prescriptions, they will themselves suggest a second pair of spectacles for nighttime driving. Even if patients prefer a single pair of spectacles for day and night, we still have the opportunity to optimize lenses for either situation, depending on the patient’s primary visual needs.
While we are able to use information about a patient’s higher-order aberrations to influence our final prescription, we are still limited by the habits of lens manufacturing laboratories. Although automated objective and subjective refraction technologies can yield prescriptions in 0.01 D increments, most lenses are still manufactured in 0.25 D steps.
Incorporating automated subjective refraction into our practice has improved our patients’ experience—and it has undoubtedly improved my experience, as well. Because I delegate the data-gathering portion of the exam to a technician, more of my time is now spent evaluating the refraction data and talking to patients about their lifestyle-related vision needs. By shifting my focus from data collection to data analysis, my days in clinic are more dynamic, enjoyable, and, ultimately, profitable—for patients as well as for the practice.
Clinicians and practice managers preparing to invest in automated subjective refraction can often look forward to significant shifts in space utilization. The Epic refraction system—our practice now has three of them—may enable traditional 20-foot refracting lanes to be rebuilt into multiple smaller examining rooms.
Incorporating this kind of refracting technology not only speeds the process but allows delegation of the data collection portion of the refraction to technicians. Faster refractions done by different members of the staff may give the practice reason to reassess patient flow and even office design. As part of the instrument sale, manufacturers will often visit the practice to assess the arrangement and patient flow and to provide assistance in helping the practice restructure for greater efficiency.
For many practices, the most significant adjustment will come from delegating refraction to technicians. This is a big step for many clinicians, particularly ODs, and while it can be a huge benefit to the practice, delegation should be done thoughtfully. These machines are technically automated, but the operator is still important.
First, care should be taken in staff selection: Using techs who are bright, experienced, and capable and who have COT training or some familiarity with optics and refraction can make for an easier process. It is also important to select those technicians with good patient rapport and handling skills.
In order to make the most of the training time and to cover for potential absences down the road, it is best to arrange a training session that includes multiple technicians. Finally, wherever possible, it is desirable to train at least one technician who has demonstrated a stable career and is likely to stay with the practice.
Investing in the Future
The eyecare practice of the future will almost certainly be heavily digital—as many eyecare practices are today. And for practices that still have not taken the EHR plunge, automating eyecare’s core testing process—the manifest refraction—may be a good place to begin.
When determining whether to invest in an automated refraction system, it is necessary to take a long-range view: There will inevitably be major innovations in this technology, but these are likely to take the form of software updates and upgrades rather than significant hardware overhauls. The purchase of an automated subjective refracting technology should be viewed as the beginning of a long-lasting relationship between practitioner and manufacturer. The equipment manufacturer should be evaluated for its ability to provide advice and training, ongoing support, and software updates—and for its likelihood of being around 5 or 10 years from now.
THE BOTTOM LINE
Automating and delegating the data collection portion of the subjective refraction gives eyecare practitioners more time for clinical decision-making and patient counseling. This will free up time to see more glaucoma patients, diabetics, and emergency patients. Further, automated subjective refraction systems have the potential to yield spectacle prescriptions that are more precise, more versatile, and fully EHR-compatible.
Louis J. Catania, OD, FAAO, practices at Nicolitz Eye Consultants in Jacksonville, FL. He is a paid consultant to Marco. Refractive Eyecare managing editor Jennifer Zweibel assisted in the preparation of this manuscript.