Article Date: 5/1/2010

Retinal Care: The New Frontier
retina

Retinal Care: The New Frontier

For your practice to survive and thrive, you must embrace retinal care. Your colleagues tell you how.

FRANK CELIA, Contributing editor

Taking the leap into retinal care can be a daunting prospect. After all, retinal conditions are numerous and often worsen with great speed. For example, a third of patients who have undiagnosed macular edema will lose 15 letters of vision in just three years.1 But as is the case with other age-related eye diseases, such as glaucoma, you must do it if you want your practice to survive and thrive. The reason: Baby boomers, who comprise most of the population, are now seniors who are increasingly presenting with retinal disease.

Consider this: Six million patients remain unaware they have diabetes, a condition whose ocular manifestations often herald its discovery. Also, forecasters expect the incidence of age-related macular degeneration (AMD) to grow from 9.1 million this year to 17.8 million in 2050.2

So how, specifically, can you successfully make the leap into retinal care? By following the advice of your colleagues who've done it:

Refresh your knowledge

In principle, any optometry school graduate should be qualified to evaluate, diagnose and co-manage retinal diseases. But as a practical matter, you may want to update this skill set before advancing on the posterior segment.

Short of enrollment in a residency program — which may not be feasible for you if you run a busy practice and have a family — several other avenues exist for refreshing your education.

For instance, you can acquire retinal care knowledge by participating in the Optometric Retina Society (ORS), which offers credentialing; the American Academy of Optometry (AAO), which affords a retina diplomate credential; and the American Optometric Association, according to optometrists Diana L. Shechtman, an associate professor of optometry at Nova Southeastern University College of Optometry, and Andrew S. Gurwood, professor of clinical sciences at The Pennsylvania College of Optometry at Salus University in Elkins Park, Pa., and attending staff member at Albert Einstein Medical Center Department of Ophthalmology in Philadelphia.

Also, state optometric associations often sponsor courses in posterior segment disease, as do many optometry colleges and optometric trade shows.

Further, you should seek an O.D. or M.D. who spends a great deal of time on retinal patients, as they can show you how to identify subtle pathology in its early stages — a key element of optometric retina care, says optometrist Jeffry D. Gerson, of Shawnee, Kan.

“It's really important to have a good relationship with your referral physicians,” he says. “I find that they are often willing to let you come in and spend the day in their office, maybe once a month or on an as-requested basis, just to get experience, hands-on seeing and learning.”

Arm yourself with technology

To diagnose and evaluate retinal disease, your practice should contain scleral depressors, ophthalmoscopes, a slit lamp and condensing lenses. Other technology to consider: a digital fundus camera, imaging instruments, macular pigment optical density (MPOD) devices and preferential hyperacuity perimetry (PHP) instruments, your colleagues say.

A dilated fundus examination employing non-contact slit lamp lenses and binocular indirect ophthalmoscopy (BIO) is considered standard for all patients, as a large percentage of retinal disease patients will be asymptomatic. (See “Specific Tips For Achieving Retinal Disease Diagnosis,” below.)

Optometrist Steven G. Ferrucci, chief of optometry at the Sepulveda VA Ambulatory Care Center and Nursing Home and associate professor at the Southern California College of Optometry, in Fullerton, Calif. recommends you use digital condensing lenses.

“They provide superb evaluation of the fundus, while minimizing internal reflections. I have several of these lenses and am impressed by the clarity of the image, which is far superior to the 90D or 78D lenses I used while in school,” he says. “I find the digital wide field lens is great for an overall view of the fundus, and both the digital high magnification and digital 1.0 lenses are great for evaluating pathology in finer detail, with better stereopsis and increased clarity and resolution without reflections.”

Although no major eyecare professional organizations have endorsed digital cameras, imaging instruments, MPOD devices or PHP instruments as standard of care, many optometrists increasingly see them as de facto necessities.

“Photo documentation of retinal pathologies is the best way to capture, preserve and follow lesions during the period of diagnosis and recovery,” says Dr. Gurwood. “Once captured, a lesion can be studied at length without inconveniencing the patient, and easily shared online with colleagues who might provide further insight.”

He adds that imaging instruments, such as spectral domain optical coherence tomographers (SD-OCTs), are important for the detection and evaluation of retinal disease as well:

“The new optical coherence technologies permit clinicians to obtain three-dimensional high resolution images of the retina and to a lesser degree, choroidal tissues. Since the only other methods of examining these structures with greater detail is by either extensively looking at them with funduscopic contact lenses or indirect ophthalmoscopy or using the more invasive fluorescein or indocyanine green angiographic techniques, these painless and risk-free image capture systems offer a distinct advantage,” he says. “Further, once captured by the instrument, the digital images can be manipulated in a number of different ways to both educate patients and yield more information. The stored images permit limitless analyzation and can be compared against new images for objective, quantitative signs of improvement or worsening.” Dr. Gurwood says another advantage the technology provides is that you can share the images electronically with colleagues or experts to get their opinions.

MPOD devices allow for the functional and structural testing of suspected or established AMD patients, as they assess risk and monitor progression. A low MPOD may be associated with an increased risk for AMD.3 These devices — QuantifEYE (Zeavision) and MacuScope Scope (Marco) — employ a technique called heterochromatic flicker photometry (HFP), which screens for low MPOD. Both use flickering blue and green light targets to yield an MPOD measurement in density units (du).

“I often use this device to validate the use of certain nutritional supplementation in some AMD patients and track its benefits over time,” says Dr. Shechtman.

For practitioners without much faith in patient compliance to Amsler grids, a PHP instrument is the answer, as it detects early conversion from non-exudative (“dry”) AMD to the neo-vascular (“wet”) form of the disease, says Dr. Shechtman. The patient uses a touch screen to identify flashing dots that have a deviating signal on distinct areas of the macula. Two such devices, the Foresee PHP (Reichert) and the PreView PHP (Carl Zeiss), are available.

“I do find [these instruments] useful in evaluating the conversion of intermediate dry AMD to wet AMD,” she says. “I find it to be a reliable test of function in patients who have AMD. I typically use the data in conjunction with other tests like OCT and a comprehensive eye exam to help with diagnosis and a proper management plan.”

Specific Tips For Achieving Retinal Disease Diagnosis

1. Recline the patient. During BIO, recline the patient to a horizontal position, as doing so allows for better access to peripheral retinal views, says Dr. Gerson. Also, perform scleral indentation when necessary.

2. Locate the center of the macula. Do this during the fundus examination and on a digital photograph to enable you to identify subtle diabetic macular edema, says Dr. Semes.
“If I can see good topography and good definition, that is a little reassuring,” he says. “But if I'm at all suspicious — and that would be if the patient has had diabetes for a long time and there is a change in vision — then at the slit lamp I'm going to pass a very fine beam from the disc across the macula, looking for any thickening or distortion. That is typically a monocular clue, which will then cause me to look stereoscopically for any areas of elevation or thickening.”

3. Don't forget the vitreous. “The vitreous is the most under-examined tissue in the eye because everyone focuses on the lens or the retina,” says optometrist Joseph J. Pizzimenti, of Fort Lauderdale, Fla. “However, evaluation of the vitreous can enable you to identify red blood cells or pigment cells, which can be a sign of conditions like retinal break or detachment.”

Investigate nutritional supplements

With the widespread acceptance of the results of the 2001 Age-Related Eye Disease Study (AREDS), nutritional treatment for AMD patients has become more common. The keystone AREDS data reveal that high intake of antioxidants and zinc lowered the risk of AMD disease progression by 25% in patients who had intermediate or advanced disease.4 Since then, other studies have shown the benefits of lutein, zeaxanthin and omega-3 fatty acids on AMD.

“What it seems is the AREDS formula should be modified to include some lutein and perhaps some zeaxanthin,” says optometrist Leo Semes, professor of optometry at the University of Alabama-Birmingham. “The discussion I have with patients is that although AREDS showed the greatest benefit for patients who had more advanced AMD, the disease does not just start out at its advanced stage; it begins in its earliest stage, and if that patient is at risk I strongly recommend that supplementation might be valuable. It's up to them, but that's what I recommend.”

He adds that at-risk patients would include anyone older than age 50 who has drusen, pigment changes or a family history of AMD.

“I would begin with 6mg per day of lutein and go to 10mg or even 20mg with higher risk,” he adds. “zea xanthin is typically dosed at 2mg per day.”

One caveat: Ask whether the patient is a smoker prior to prescribing a nutritional supplement, so you can prescribe a supplement that doesn't contain beta-carotene. A post-AREDS finding revealed that high levels of beta-carotene are associated with an increased incidence of lung cancer among heavy smokers.4 (See “Kicking the ‘A’ Out of AMD,” February OM, for the financial benefits of MPOD and nutrition.)

At this point, you're no doubt wondering how making the leap into retinal care will affect office flow and your staff. Changes required tend to be minimal, says Dr. Gerson.

About 5% to 10% of Dr. Gerson's patients have retinal concerns, but they require no special scheduling to maintain office flow, he says. His practice already distinguishes between “routine” and “non-routine” exam follow-up visits, so retina patients simply fall under nonroutine, which allots slightly more time. Dedicating an office day exclusively to retinal patients would require much greater volume, he says, or else be confined to one day a month, a schedule unlikely congenial to patients.

Know when to refer

A good clinician should refer any finding he or she is unsure of, says Dr. Gurwood. Also, many published guidelines can help you, as they delineate treatment thresholds, supporting the conclusions that were made with statistical and mathematical data, he adds.

For example, if you're unsure about thresholds for treating proliferative diabetic retinopathy, Google the Diabetic Retinopathy Study (DRS). Uncertain whether a diabetic macular edema case is clinically significant? Google the Early Treatment of Diabetic Retinopathy Study (ETDRS). Wondering when a diabetic with vitreous hemorrhage requires a vitrectomy? Google the Diabetic Retinopathy Vitrectomy Study (DRVS).

Keep in mind that these are just the National Eye Institute-sponsored studies (much of this information is available at: www.nei.nih.gov). The literature abounds with similar reference guidelines, Dr. Gurwood points out.

Fifteen years ago, optometrists who chose to take on medical eye care likely did so for enhanced professional fulfillment, an expanded income or to offer better treatment than the competition in remote rural areas. Now, however, providing medical care is more a necessity than a choice, as shifting age demographics are driving an overflow of serious ocular disease into your practice. The bottom line: If you haven't done so already, it's time you take the leap into retinal care. OM

  1. Gangnon RE, Davis MD, Hubbard LD, et al. A severity scale for diabetic macular edema developed from ETDRS Data. Invest Ophthalmol Vis Sci. 2008 Nov;49(11):5041-7.
  2. Rein DB, Wittenborn JS, Zhang X, et al. Vision Health Cost-Effectiveness Study Group. Arch Ophthalmol. 2009 Apr;127(4):533-540.
  3. Nolan JM, Stack J, O'Donovan O, et al. Risk factors for age-related maculopathy are associated with a relative lack of macular pigment. Ex Eye Res. 2007 Jan;84(1):61-74.
  4. AREDS Group. A randomized, placebo-controlled clinical trial of highdose supplementation with Vitamin C and E, beta carotene and zinc for AMD and vision loss: AREDS report no. 9. Arch Ophthalmol 2001 Oct;119(10):1439-52.
Mr. Celia is a freelance healthcare writer based in the Philadelphia area.


Optometric Management, Issue: May 2010