Article Date: 2/1/2011

The Practice Advantage

The Practice Advantage

Learn how automated refractions can provide a competitive edge.

By Kim Castleberry, OD

“All I want in practice is an unfair advantage”—and that's what I feel 3-D Wave automated refraction affords my practice. If technology integration is the hallmark of our practice, then Wavefront evaluation is at the center of that technology. Marco's 3-D Wave takes me back to the future of eye care; back to the basics of well vision care and forward to the future of medical eye care. Significantly, it accomplishes this with a remarkably small footprint, 12 inches x 21 inches.

Most ECPs are familiar with the 3-D Wave's ability to provide advanced well vision care but less familiar with its impact on medical and surgical management of eye disease. The 3-D Wave is perhaps the most underutilized and misunderstood of all diagnostic technologies. Here, I will discuss the capabilities of the Marco 3-D Wave instrument and how it can increase your scope of practice. The 3-D Wave is not for every OD, but I'm hoping my insights will help you determine if your practice is a good candidate for this technology.

The 3-D Wave collects over 6,840 data points in the eye including 1440 Wavefront measurements. Perhaps most amazing is that this data is collected in one station at one time during the patient visit. These data points fall into four categories.

■ Automated refraction
■ Wavefront analysis
■ Corneal topography
■ Pupillometry

This data can help you provide advanced well vision refractive care. Moreover it can assist in the medical and surgical management of eye disease. Let's take a look at each category.

Automated Refraction

Automated refraction data is collected at the 2.5-mm, 3-mm and 5-mm zones. Wavefront refraction is measured across the entire eye using vector analysis to enhance the sphere, cylinder and axis. The more accurate of this data statistically is identified on the evidence document and transferred into the EHR and/or electronic refractor. At that point, a spherical refinement/verification can be done in about 30 seconds. Infrequently, a cylinder refinement is required with the advanced knowledge of the exact extent and amount of internal and corneal astigmatism. Irregular astigmatism is broken down into its high-order components and available for review as well. Quick comparison to other prescriptions can be done at the click of the button to determine if optical correction will solve the problem, or if surgery or other diagnostic testing is needed.

Mesopic and photopic pupil measurements are captured and coupled with the Wavefront and zonal refraction data at 2.5 mm, 3 and 5 mm, so the optometrist can accurately prescribe for day and night vision conditions.

The power range of the instrument is −20 to +22 diopters of spherical error and 0 to -12 diopters of cylinder. PD's can also be measured with this device and we often use this data when prescribing eyeglasses.

Our 3-D Wave has reduced the amount of refraction time in our office dramatically. Our doctors like the reduced chair time and patients love not having to answer which is better, one or two.

Remember that excess working distance can lead to erroneous data, which is why technicians are trained to check patient position before measurement begins. Furthermore, dirt smudges or debris in the system optics can distort data, so it's critical that the system be kept clean.

The internal OPD map shows optical aberrations behind the surface of the eye.

The OPD map shows all optical aberrations in the eye.

Wavefront Analysis

The 3-D Wave uses Dynamic Skiascopy technology (a scanning infrared slit refractometer) to measure the refractive power and Wavefront analysis of the entire optical system of the eye. Several metrics quantify the high-order distortions to vision:

■ Root mean square (RMS)
■ Zernike coefficients
■ Point spread function (PSF)
■ Total optical path difference (OPD)
■ Internal OPD
■ Total wavefront
■ Higher-order Wavefront

These metrics provides diagnosis and management capability for a wide variety of ocular diseases.

■ Reduced BCVA ICD: 368.8
■ Subjective visual disturbance ICD: 368.1X
■ Lenticular disease ICD: 366.XX
■ IOL complications ICD: 996.53
■ IOL opacity ICD: 366.5

Point spread function shows how the High Order aberrations appear to the patient with trefoil.

Axial map showing corneal wavefront topography.

Eye image showing mesopic and photopic pupils and angle kappa for both.

Corneal Topography

The 3-D Wave contains a Placido Disc Corneal Topography collection system to measure 11 mm of corneal surface. In addition, 19 vertical and 23 horizontal rings, measuring 360 individual points, are utilized to capture 6,840 data points, leaving little to extrapolation. Algorithms allow for axial, instantaneous (tangential), refractive and elevation maps for comprehensive evaluation of the cornea. Moreover, it provides diagnostic care for a wide range of corneal and lid or conjunctival-induced corneal deformities. We've also found the video imaging capability helpful for some cases of eyelid drooping, pterygium and IOL complications.

■ Corneal degenerations ICD: 372.XX
■ Corneal deformities ICD: 372.XX
■ Corneal dystrophies ICD: 372.XX
■ Eyelid induced deformities: 374.XX
■ Pterygium ICD: 372.4X
■ Refractive surgery & complications ICD: V45.XX
■ Contact lens care & CRT ICD: 367.XX

Pupillometry

Video image detection provides mesopic and photopic pupil measurements under moderate and high light conditions. We've found that adding 1-2 mm to the mesopic pupil measurement provides an accurate scotopic pupil measurement for most patients, simulating night time pupillometry. Coupled with known optical zone characteristics of contact lenses, ablation zones, IOLs and cataracts, pupillometry can be a big help in the management of eye disease and vision disorders.

Billing & Coding With the 3-D Wave

No discussion of diagnostic technology is complete without commenting on reimbursement issues. I use the following codes for 3-D Wave procedures but guidelines and carrier policies vary, so always consult a coding expert on reimbursement issues.

99XXX, 92XXX or S062X code for the associated exam

92025 for corneal topography

92285 for external photos for photographic quality images of sufficient quality to be clinically relevant

V278X for premium IOL management (Billed to the patient). Wavefront analysis is a significant portion of my premium IOL evaluation and management fee billed to the patient as part of the premium IOL package. Premium IOLs include toric, accommodative, multifocal and aspheric.

Wavefront Advantage

It has been several decades since automated refractors replaced the retinoscope, making computerized refraction the new standard in eye care. Perhaps it's time to consider a new paradigm to differentiate your practice and increase the scope of care offered to your patients. I'm surprised Wavefront isn't the new standard of care but I suspect that day will soon come. Until then, I will enjoy my unfair advantage.


Dr. Castleberry is CEO of Plano Eye Associates, Plano, Texas. E-mail him at KimCastleberry@planoeye.com.

Optometric Management, Issue: February 2011