I had the pleasure of attending the Envision Conference in San Antonio last week. This was my first time attending this multidisciplinary low vision conference, but will hopefully not be my last.

It was a great joy to see so many people devoted to serving the vision impaired community. Especially enlightening to me was the large number of occupational therapists currently involved in delivering low vision therapy. This began in 2005 with changes in Medicare billing regulations that opened the door to the delivery of low vision services by occupational therapist.

Another specialty that was well-represented at the conference were orientation and mobility (O&M) specialists. These professionals help people with visual impairments learn to travel independently, including training them to use assistive devices such as handheld telescopes, white canes, service animals, or GPS systems. Unfortunately, these professionals are not currently able to bill Medicare for their services.

During the ongoing Medicare low vision demonstration project in select U.S. States, O&M specialists are be able to provide medically necessary services and these services are reimbursable by Medicare. However, this project is scheduled to conclude in 2011, and at that time the U.S. Office of Management and Budget (OMB) will make a determination as to whether or not to expand Medicare coverage for low vision services nationally.

It is certainly our hope that OMB will make the right decision and recognize the valuable and medically necessary services that O&M specialists provide.

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Good visual outcomes can be achieved without surgery in patients with choroidal neovascularization (CNV) that develop vitreomacular traction (VMT), according to a new study.

Adhesion between the retina and vitreous occurs regularly in patients with AMD and may cause traction in eyes with CNV. In addition, it has been suggested that these tractional forces may then impede the effectiveness of anti-VEGF treatment.

In this retrospective case series, 7 eyes of 7 patients with VMT were monitored with optical coherence tomography (OCT). The mean age at presentation was 74 years. The etiology of CNV was wet AMD in five eyes (72%), angioid streaks in one eye (14%) and pathological myopia in one eye (14%). Lucentis was used in four eyes (57%) and Avastin in three (43%) for active CNV. The mean follow-up was 11 months.

None of the eyes in this study received surgery for VMT, nor were there any cases of spontaneous resolution of VMT. Visual acuity was stabilized or improved in five of the seven eyes (71%) with anti-VEGF therapy. Visual acuity results across the whole group were gain of three or more lines of Snellen visual acuity in two eyes (28%), gain of less than three lines in three eyes (42%), no change in visual acuity in one eye (14%) and loss of up to three lines in one eye (14%). There were no eyes losing more than three lines of Snellen visual acuity. In four eyes with pre-existing VMT, visual acuity improved in three with anti-VEGF therapy. In three eyes that developed VMT after anti-VEGF therapy was initiated, visual acuity improved in two.

The researchers conclude that most eyes improved visual acuity with anti-VEGF therapy for combined CNV and VMT. Despite the often dramatic features of VMT on OCT, vitreoretinal surgery was not required in this series.

WHAT IT MEANS TO YOU: There is good evidence that the vitreous plays an important role in the onset and progression of AMD. A recent study found that surgical removal of the vitreous decreased the rate progression of AMD. This study finds that patients can benefit from anti-VEGF therapy despite OCT evidence of vitreomacular traction. This is not really very surprising. More interesting would be a study that compares outcomes of patients undergoing anti-VEGF therapy for CNV that undergo vitreoretinal surgery for VMT with patients that do not have surgery.

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Patients that do well on long-term anti-VEGF therapy are those who show a good response to the first three treatments, according to research presented at the 2010 Euretina meeting in Paris.

Unfortunately, not all AMD patients on anti-VEGF therapy experience an improvement in vision, and there is currently no way of predicting which patients will respond well and which will deteriorate despite treatment.

In a retrospective study, potential prognostic factors were evaluated, including baseline best corrected visual acuity, type and size of choroidal neovascularization (CNV) evaluated by fluorescein angiography, central retinal thickness, and amount of subretinal fluid. Response to the 3 monthly injections of the loading phase was also evaluated.

"We found that the best prognostic factor is the response to the first three treatments. Patients with improved BCVA and absent signs of leakage at the time of the third injection had the greatest improvement in [visual acuity], the largest decrease in retinal thickness and needed less re-treatment," Dr Frank D. Verbraak said.

WHAT IT MEANS TO YOU: We expect patient's vision to improve on anti-VEGF therapy. In the MARINA and ANCHOR trials of Lucentis for neovascular AMD, there was an average improvement of 7.2 letters and 11.3 letters, respectively. Unfortunately, not all patients improve, and some patients may even get worse despite treatment. It is not entirely clear why some patients do more poorly than others, and it is not possible at the present time to predict which patients will be non-responders. However, this study indicates that the patient's response to the first 3 injections are a valuable indicator of how they will do long-term.

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Avastin is more effective than photodynamic therapy (PDT) for the treatment of subfoveal choroidal neovascularization (CNV) secondary to multifocal choroiditis (MC).

Multifocal choroiditis (MC) is a chronic inflammatory disease that most frequently occurs in women in the third to fifth decade of life. Visual prognosis in patients affected by MC is generally good except for patients developing macular complications, such as foveal inflammatory scarring, cystoid macular edema, epiretinal membrane, and CNV. Corticosteroid and immunosuppressant therapy have been reported to be beneficial in controlling the inflammation related to MC, but safety and side effects are still debated.

In this study, 27 patients with subfoveal CNV associated with MC were included in the study. After randomization, patients receiving PDT were treated with a standard full-fluence PDT protocol, whereas patients receiving intravitreal Avastin injection were re-treated as needed after a 3 month induction period.

Thirteen and 14 patients were randomized to PDT and Avastin treatment, respectively. At the 12-month examination, 5 of 14 eyes treated with Avastin and 0 of 13 eyes treated with PDT experienced a BCVA gain of greater than 3 lines. Twelve eyes in the Avastin group and 6 eyes in the PDT group gained more than 1 line. The central macular thickness showed a progressive reduction in both subgroups without a significant difference compared with the baseline values.

In an attempt to assess the most beneficial treatment option for subfoveal MC-related CNV, this study compared Avastin and PDT. The results show that Avastin is superior to PDT in improving the mean BCVA during a 12-month follow-up. As previously reported, PDT can lead to a stabilization of visual acuity with limited functional improvement.

The investigators conclude that greater beneficial effects can be achieved using Avastin rather than PDT for the treatment of subfoveal CNV secondary to MC.

WHAT IT MEANS TO YOU: MC affects younger people than AMD. In the current study, the average patient age was 39 years. This suggests that if anti-VEGF therapy is the treatment of choice for MC, then these patients may need to undergo intravitreal injections for many decades. This is a serious problem from a safety, convenience and a cost standpoint. In the current study, patients were examined monthly and received an average of about 4 Avastin injections over the 12 month follow-up period. It is unclear whether more or fewer injections would be required over longer follow-up. Clearly, a treatment that would destroy the neovascular membrane and remove the stimulus for recurrence is needed. Perhaps combining Avastin with other treatment modalities, such as reduced-fluence PDT or steroids would decrease the need for re-treatment.

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VEGF antagonists, such as Avastin (bevacizumab) and Lucentis (ranibizumab), impair the barrier function of cultured retinal pigment epithelium (RPE) cells, according to a new study.

Several adverse incidents are related to anti-VEGF therapy, such as RPE tear and intraocular inflammation. The mechanisms of these adverse drug effects are still a matter of speculation.

Tight junctions between RPE cells function as the outer blood-retinal barrier, which restricts diffusion between the retina and choroid. It is possible that anti-VEGF treatment disturbs the barrier, perhaps by influencing RPE permeability.

In this study, RPE cells from pig eyes were cultured in a laboratory. The cells were exposed to Avastin or Lucentis. Transepithelial flux of FITC-dextran wwas investigated at different points in time. The influence of the addition of a steroid (triamcinolone acetonide, TA) was investigated.

The researchers found that Avasatin and Lucentis induce increased permeability of cultured retinal pigment epithelium, with a stronger and longer lasting effect seen with Avastin, suggesting that these drugs might decrease RPE barrier function. In general, the effect seen with Avastin was more profound than with Lucentis.

The researchers speculate that anti-VEGF treatment increases the natural risk for RPE tears. Several potential mechanisms have been proposed, including rapid resorption of the sub-RPE fluid and contraction of the CNV. Additionally, the disturbance of RPE barrier function, as suggested in this study, might be one of the participating mechanisms.

TA stabilized RPE permeability indicating that TA has a protective effect on RPE junctions. It is conceivable that TA might reduce the rate of RPE tear induced by anti-VEGF drugs.

The investigators conclude that Avastin and Lucentis may decrease RPE barrier function, with Avastin exhibiting a prolonged and more profound effect. Combination therapy with TA may be beneficial.

WHAT IT MEANS TO YOU: This study finds that both Avastin and Lucentis impairs a critical function of the RPE, restricting the flow of material from the choroid into the retina. The impairment was greater and longer lasting with Avastin than with Lucentis. The clinical significance of this finding is unclear, but the researchers suggest that it may be related to the development of RPE tears following anti-VEGF therapy. Such a relation needs to be confirmed by future research. In any event, this study is yet another indication that long-term dependence on anti-VEGF therapy is less than ideal, and treatments directed at the eradication of choroidal neovascularization are needed.

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A moderate association of high blood pressure with AMD was found in a large population-based study involving several cities in France.

"Blood pressure has been suggested to be implicated in the etiology of ARM; however, epidemiological data are scarce and contradictory in this field," Dr Jean Francois Korobelnik said at the Euretina meeting in Paris.

Most published studies rely on a single measurement of blood pressure, according to Dr. Korobelnik. The main strength of the ALIENOR (antioxydants, lipides essentiels, nutrition et maladies oculaires) study, he said, is that there was a long-term assessment of blood pressure status, which was measured over a 7-year period.

A total of 963 subjects aged 74 years or older were included.

"Hypertension was associated with a moderate increase in the risk for ARM. This association appeared similar across the different types of ARM," Dr. Korobelnik said.

WHAT IT MEANS TO YOU: It has long been recognized that AMD shares many risk factors with cardiovascular disease. Smoking, obesity, and C-reactive protein levels have been associated with both conditions. Recently, a study found that lowering homocysteine levels with a folic acid supplement could prevent the onset of AMD. Homocysteine is strongly associated with heart disease and stroke. Most studies have failed to find an association between blood pressure and AMD, but as noted above, this study closely monitored blood pressure over a 7-year period. It may turn out that following a heart-healthy lifestyle can significantly reduce the risk of developing AMD.

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A device designed for in-home, self-administered testing may find utility in monitoring patients with intermediate AMD. In the ForeseeHome test (Notal Vision), patients are tasked with identifying and marking locations of artificially displaced dots on horizontal or vertical dotted lines. Patients may perceive additional displaced dots if the line is flashed at the spot of a CNV lesion. In this prospective study, abnormal test results were identified in 27 of 32 eyes with CNV and in three of 22 eyes with intermediate CNV, which corresponded to a sensitivity of 84%, a specificity of 86% and an accuracy of 85%. "I think that the device would be most beneficial for patients with non-neovascular AMD who are in need of monitoring," study author Dr. Loewenstein said. Studies are being performed to test the utility of the device in patients treated with an anti-VEGF regimen, either to signal a return of fluid on the macula or to prompt re-treatment. The study was published in the journal Retina.

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The U.S. Food and Drug Administration has granted priority review status to Alimera Sciences' new drug application for its Iluvien intravitreal insert to treat diabetic macular edema (DME), the company announced in a press release. Alimera is currently conducting two pivotal phase 3 trials, known as the FAME Study, to assess the efficacy of both high- and low-dose formulations of Iluvien (sustained release fluocinolone acetonide). The study, which will end later this year, involves 956 DME patients. "If approved, we believe that Iluvien will be the first pharmaceutical in the U.S. indicated to treat this disease, and the first long-term treatment with the potential to be therapeutically effective for up to 36 months," Dan Myers, president and CEO of Alimera, said in the release.

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Information gathered from the peripheral retina may be important for the diagnosis and management of macular disease. In a retrospective analysis of patients using Optos' ultra-widefield retina imaging, 76% had abnormalities in the peripheral retina, or outside the central 30 degrees that would normally be seen with standard autofluorescence. The Optos imaging device offers up to 200 degrees of view within the eye, constituting about 82% of the total retina in a single image. "The clinical significance of these findings requires further investigation but demonstrates the importance of understanding changes in the periphery of the retina," said investigator Dr Srinivas Sadda. Optos has announced that the technology will be used in the AREDS2 study to monitor effectiveness of study treatments. The proprietary technology may also prove useful in helping to define phenotypic expression of retinal pathologies with a genetic link, investigators said.

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Macular edema due to branch or central retinal vein occlusion can be effectively reduced using the Ozurdex dexamethasone intravitreal implant, but early treatment is mandatory, according to data from the multicenter GENEVA study. "Patients who were treated early showed a visual acuity improvement of three or more lines, but treatment delay and [macular edema] progression was associated with a significantly lower likelihood of regaining vision," Dr Paolo Lanzetta said at the Euretina meeting in Paris. "In the sham group, where active treatment was started at 6 months from baseline, the chances of gaining three or more [visual acuity] lines were 70% lower," he said. These findings could potentially represent a paradigm shift in the approach to retinal vein occlusion. Until last year, no early treatment was recognized to alter the visual prognosis of established retinal vein occlusion, and laser photocoagulation was recommended after an observation period between 3 months and 6 months. "We have now proven that there is no rationale in delaying treatment," Dr. Lanzetta said. "As soon as the diagnosis is formulated, patients should receive Ozurdex treatment with no further delay."

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