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Is Your Practice Ready for Age-Related Eye Disease?

Follow these six tips to prepare your practice for the imminent influx of glaucoma, cataract, diabetic retinopathy and age-related macular degeneration patients.

JOSEPH J. PIZZIMENTI, O.D., F.A.A.O., Ft. Lauderdale, Fla.

Our nation's baby boomers have entered their senior years. Couple this with the fact that the prevalence of several eye diseases increase with age, and it becomes obvious that the combination of these two factors will soon result in a dramatic increase in vision impairment and loss due to age-related eye diseases. Therefore, to meet these patients' needs and ensure the financial strength of your practice, you must prepare your practice for a large stream of glaucoma, cataract, diabetic retinopathy and age-related macular degeneration (AMD) patients.

Here are six tips that will enable you to do this.

1 Hone your diagnostic skills

To properly diagnose and manage glaucoma, you must be adept at performing standard testing, such as gonioscopy, optic nerve and nerve fiber examination. In addition, you must be skilled at interpreting the results of this standard testing. Other mandatory diagnostic equipment for the proper management of glaucoma: a threshold perimeter and pachymeter.

Direct ophthalmoscopy enables you to see the living retina and optic nerve. It's quick and easy to perform, with good examiner control and 25X magnification. Further, its' red-free filter enables you to detect lens opacities, retinal microaneurysms, small hemorrhages and vitreous opacities.

Because the use of a contact or non-contact fundus lens in conjunction with a slit lamp is an excellent way to evaluate the central, mid-peripheral and peripheral retina as well as the optic disc and nerve fiber layer, you must be adept at performing and interpreting the results of fundus biomicroscopy. In addition, a fundus camera is essential for any practitioner who's serious about glaucoma and retinal disease management, as it enables you to track disease progression and the effectiveness of your prescribed treatment through time. Ultra Wide-field Retinal Imaging technology (Optos), for instance, provides a 200° digitally enhanced panoramic image of the retina.

Finally, no posterior segment examination is complete without binocular indirect ophthalmoscopy through a maximally dilated pupil. To yield useful information about clinical entities, such as retinal breaks, you must be skilled at scleral indentation, which enables you to view the peripheral retina in profile.

It's important to remember, however, that new technology is also available to aid in the detection and management of age-related eye diseases and may be worth your while. (See “How to Evaluate New Technology For Your Practice,” below.)

To hone your examination and diagnostic skills, attend state, regional and national continuing education meetings, which offer procedure- and technology-related workshops. Also, keep in mind that colleges of optometry hold periodic, comprehensive ocular disease symposia in a lecture/lab format. So, you should look into attending these meetings as well.

2 Effectively comanage patients

Cataract, glaucoma, diabetic retinopathy and AMD patients often require surgical intervention and sub-specialty consultation. As a result, you must establish relationships with the appropriate providers, such as a retinal surgeon, to ensure the patient receives optimum care. That being said, remember that it's your job to provide the pre- and postoperative care and work in conjunction with the sub-specialist, should complications, such as posterior capsule opacity, occur.

You should comanage patients who have systemic conditions, such as diabetes, with the appropriate primary care provider (i.e. internist, cardiologist, endocrinologist).

Also, consider expanding your comanagement network to include pharmacists and nutritionists/dieticians, who are valuable members of the healthcare team and can greatly aid in the care of such patients.

For example, a top-notch clinical pharmacist can counsel your senior and/or elderly patients on drug interactions and side effects.

Meanwhile, nutritionists and dieticians can place your patients on personalized diets and also provide valuable education on the use of beneficial vitamins, herbs and supplements.

3 Utilize scanning laser technology

Scanning laser technology has ushered in a new paradigm of care for patients who have age-related ocular conditions. Indeed, the increased use of scanning lasers has reduced the necessity for the more invasive angiography. For example, optical coherence tomography (OCT) has all but replaced angiography in the evaluation of post-surgical cystoid macular edema. Other medical indications for scanning lasers include suspicion for choroidal neovascularization (CNV), lamellar and full-thickness macular defects and glaucomatous nerve fiber damage.

Because retinal thickness measurements and qualitative studies with scanning lasers enable you to identify and track structural changes that result from glaucoma, AMD, diabetic retinopathy, vitreo-macular traction syndrome, epiretinal membranes, macular holes and various “edematous” retinopathies, you should consider employing the scanning laser technologies in your practice.¹

To begin with, OCT enables cross-sectional posterior segment imaging and quantitative analysis. “Spectral domain” OCT technology, also known as Fourier domain, high definition or 3D-OCT, uses a spectrometer in conjunction with a stationary reference mirror to provide retinal thickness measurements. The lack of the device's moving parts facilitates exceptional image acquisition speed that ranges from 27,000 to 40,000. This “spectral domain” technology produces high-resolution 2D and 3D images that help you distinguish between subtle pathological changes, such as nerve fiber layer thinning, intraretinal fluid and vitreoretinal traction, and normal anatomic variations, such as optic pits and posterior vitreous detachment. As a result, OCT has enhanced our ability to diagnose and manage glaucoma and myriad retinal conditions, and it has revolutionized the evaluation of the vitreoretinal interface.

Manufacturers of these devices: Topcon Medical Systems; Bioptigen; Carl Zeiss Meditec; Optopol; Ophthalmology Technologies, Inc.; OptoVue Corp.; and Heidelberg Engineering. (For a list of device specifications, see issue of the August 2009 OM, or visit www.optometric.com/article.aspx?article=103326.)

Scanning laser polarimetry uses polarized laser light to assess the retinal nerve fiber layer's (RNFL) thickness in the peripapillary area. The GDxVCC (Carl Zeiss Meditec) provides quantitative RNFL analysis for patients who have glaucoma and other optic neuropathies, such as papillitis, anterior ischemic optic neuropathy and optic atrophy.

You may use confocal scanning laser ophthalmoscopy (CSLO) to evaluate the optic nerve and retina. For instance, the HRT 3 scanning laser polarimetry device (Heidelberg) uses proprietary technology to check and align the images, remove images that are of questionable quality and combine image sets into one 3D composite. The result: Detailed optic nerve analysis for glaucoma and reflectance and thickness maps for retinal disease.

Finally, the RTA 5 (Talia/Marco) uses scanning laser biomicroscopy to quantitatively document anatomical changes in optic nerve, retinal and subretinal tissues by measuring thickness variations and topographic changes of the chorioretinal interface. Once the RTA 5 acquires data, it presents it as color-coded 2D and 3D thickness and topography maps, deviation probability maps (from a normative database), numerical values, interactive 3D cut sections and digital fundus images.

4 Add structural/ functional AMD testing

Exudative or “wet” AMD is characterized by CNV, which may be accompanied by lipid exudation, sub-retinal pigment epithelium (RPE) fluid, RPE tears and detachments, retinal edema and hemorrhage. This leads to damage of the neurosensory retina. Irreversible, severe vision loss is frequently linked with fibrovascular “disciform” scar formation, marking the end stage of the disease.

As is the case with glaucoma, to best monitor AMD you must use both functional and structural testing. Quantifying macular pigment optical density (MPOD) in a clinical setting with heterochromatic flicker photometry (HFP) is a structural test for AMD. Low MPOD may be associated with an increased risk for AMD.² Also, many studies have shown that low MPOD may be linked with several other risk factors for AMD, such as smoking, obesity and systemic vascular disease. HFP is a psychophysical technique that uses flickering blue and green light targets to yield an MPOD measurement (in density units). It doesn't depend on pupil dilation, but it does require tester training to yield reliable results. The two instruments currently available for MPOD measurement: QuantifEYE (Zeavision) and Macu Scope (Marco).

Functional deficits may occur simultaneously with, or even prior to, observable AMD structural change(s). For this reason, in addition to structural tests, employ visual function tests. These include logMAR visual acuity, Amsler grid, photostress recovery, contrast sensitivity and/or even electroretinography.

Also, Preferential Hyperacuity Perimetry (Foresee PHP, Notal Vision/Sightpath) enables you to monitor patients who have AMD, as it detects early conversion from non-exudative (“dry”) AMD to the neovascular (“wet”) form of the disease. Specifically, PHP tests the central 14° of visual field. The patient uses a touch screen to identify flashing dots that have a deviating signal on distinct areas of the macula.³

The PHP uses hyperacuity, or Vernier acuity, rather than white light. Hyperacuity is the eye's ability to detect subtle misalignment of an object (relative to other objects) in space, also known as spatial localization. It's 10 times more sensitive than Snellen acuity.³ The device maps hyperacuity visual field defects. Also, the PHP analysis provides reliability indices, including false positive and negative responses. Additionally, the analysis reveals the existence of a corresponding visual field defect zone within the macular area. Finally, it provides you with general recommendations for further disease management. A recent study showed that PHP had an 88% specificity rate in differentiating CNV from the intermediate stage of dry AMD, and an 82% sensitivity rate in accurately detecting newly diagnosed CNV.⁴

5 Educate staff

New technology requires staff acceptance and education. This not only helps the staff educate and operate the technology on patients, but it also enables optometrists who run large practices to confidently delegate testing procedures to skilled staff members. Most manufacturers and distributors provide staff support and initial training. I've discovered that a staff that is empowered with knowledge about why what they do is important is more apt to thrive in a busy, well-equipped practice.

Consider sending select staff members to workshops, which are offered at several state, regional and national continuing education meetings, so they can hone their testing skills.

6 Accurately code for reimbursement

Proper billing and reimbursement can provide data for quality assurance, performance improvement, risk management and research activities. (See “Age-Related Eye Disease Procedure Codes,” below.)

Before you know it, older persons will comprise most of eyecare's patient base. Therefore, you must take the aforementioned steps to ready your practice for glaucoma, cataract, diabetic retinopathy and AMD patients. Not doing so will result in these patients seeking care elsewhere — something that could have major effects on your bottom line. OM

E-mail jen.kirby@wolterskluwer.com for the list of references.

Dr. Pizzimenti is an associate professor at Nova Southeastern University College of Optometry in Ft. Lauderdale, Fla. He is a frequent speaker and writer on age-related eye disease. He is also a Baby Boomer. E-mail him at pizzimen@nova.edu.