Global study reveals burden of AMD on quality of life, health care systems

At the recent pan-European retina meeting, advanced surgical techniques and equipment were presented.

LISBON, Portugal — A five-nation study found that patients with age-related macular degeneration reported substantially worse quality of life and a higher rate of comorbid medical conditions than a control group of elderly patients without AMD.

Daniel Pauleikhoff, MD, said here at the Euretina meeting that patients with AMD also had higher health care utilization rates, significantly worse visual acuity and a twice-greater risk of suffering falls than the control group.

The study was carried out in Canada, France, Germany, Spain and the United Kingdom, and was based on 872 telephone interviews. Of those interviewed, 401 had bilateral AMD. The other 471 age-matched participants did not have AMD.

Patients with AMD had “significantly more comorbid medical conditions (2.5) than the control group (2.2),” Dr. Pauleikhoff said.

Those with AMD also had twice the risk of suffering a fall as the control group (17% vs. 8%). Twenty-nine percent of those with AMD required daily living assistance; 7% of the participants without AMD required daily living assistance.

“Patients [with AMD] reported significantly higher humanist and economic burdens in the activities of daily living compared to control patients,” Dr. Pauleikhoff said.

More presentations from the conference are highlighted in the remainder of this article. These items appeared first on the OSN SuperSite as daily reports from this meeting. Look to the print pages of an upcoming issue for expanded coverage of selected items.

Radial optic neurotomy still a valid CRVO treatment

Physicians should not discount radial optic neurotomy as a treatment for central retinal vein occlusion, said one speaker.

Marcelo Zas, MD, performed a retrospective review of 17 patients with ischemic central retinal vein occlusion who underwent radial optic neurotomy between 2003 and 2005. All patients had vision of 20/400 or worse at baseline, Dr. Zas said.

Each of the patients underwent pars plana vitrectomy, including an extraction of the posterior hyaloid, and a neurotomy on the nasal side to relax the scleral outlet, Dr. Zas told attendees.

He said 13 patients improved their visual acuity to a range of 20/200 to 20/60. “There were no postoperative complications at up to 24 months,” he said.

Of the remaining four patients, three developed anterior segment neovascularization with secondary glaucoma and the fourth developed a rhegmatogenous retinal detachment secondary to pars plana vitrectomy and required a second surgery, Dr. Zas said.

Technique uses dye to find retinal breaks

A novel technique for identifying retinal breaks following rhegmatogenous retinal detachment using trypan blue was introduced during the meeting.

Upon occasion, the surgeon may be unable to locate a patient’s retinal break, said G. William Aylward, MD. When that occurs, the surgeon must “cover all of our options by doing an encircling buckle or 360° laser,” which is not an ideal solution, he said.

In such cases, “subretinal dye has a useful but occasional role in identifying missing retinal breaks during vitrectomy,” Dr. Aylward said.

In his technique, trypan blue is injected into the subretinal space through a 40-gauge cannula.

“In our early cases we used small volumes of dye, but we have found that larger volumes – up to 1 mL – give better staining, particularly in bullous detachments,” Dr. Aylward said. After the dye is initially injected, it forms “a kind of thumbs-up sign,” and Dr. Aylward said he knows he will have a good result from there.

The surgeons must be patient and allow time for the dye to diffuse through the subretinal space, he said. He injects perfluorocarbon liquid to fill the eye and force the fluid peripherally.

The dye will then form “what looks like an arrowhead,” revealing the location of the break, he said.

“More important, it shows where the breaks are not,” Dr. Aylward said

In a small case series of five patients, only the first patient’s retinal break remained unidentified with the modified technique, and Dr. Aylward said the small amount of trypan blue used did not affect the outcome.

Toxicity is not a factor, Dr. Aylward said, because a low concentration (0.15%) is used. The dye is in the eye for a short time and is washed out after identifying the break, he said.

Nd:YLF laser promising for DME

A multicenter pilot study found that neodymium:YLF laser treatment of selected retinal pigment cells is promising for treatment of diabetic macular edema, Peter Hamilton, MD, FRACS, told attendees.

He said the Nd:YLF laser selectively treats retinal pigment epithelial (RPE) cells by creating a thermal reaction within the RPE at between 100° and 160°. The reaction is confined to the RPE, he said.

Selective treatment of RPE “avoids photoreceptor damage and central visual field defects,” Dr. Hamilton said.

The Nd:YLF laser used in the study has a wavelength of 527 nm, pulse duration of 0.2 seconds, spot size of about 200 µm, and pulse rate of 100 Hz, he said.

The laser spots “create minimal collateral damage, allowing the sparing of the photoreceptors,” Dr. Hamilton said. He described results of a phase 1 pilot study performed in London and at three sites in Germany with 20 patients at each site.

The study graded the effectiveness of Nd:YLF laser for treatment of diabetic macular edema based on improvement of visual acuity, reduction of hard exudates, reduction of leakage on fluorescein angiography and reduction of retinal thickness as measured by optical coherence tomography, Dr. Hamilton said.

“At 6 months follow up, 90% of patients (49/55) had better or stable vision,” he reported. “Laser scars were not visible on [angiography] in 17 out of 20 eyes of the London patients.”

For the future, Dr. Hamilton recommended a trial comparing the Nd:YLF treatment to conventional argon laser.

Study: Only dexamethasone non-toxic to retinal cells

After a comprehensive study of the safety profile of steroids on retinal cells, only dexamethasone was found to be non-toxic.

During the free paper presentations, Baruch Kupperman, MD, PhD, said that while “24-hour exposure of clinically relevant concentrations of triamcinolone, betamethasone and methyl prednisolone were toxic to retinal cells,” dexamethasone was not. No preservatives were found to be toxic either, he said.

Dr. Kupperman used a trypan blue dye assay to measure toxicity. He said the study compared human retinal pigment epithelial cell lines and rat neurosensory retinal cells cultured in a 10% fetal bovine serum medium.

“The data showed triamcinonolone was toxic at 2, 6 and 24 hours,” Dr. Kupperman said. “Dexamethasone showed no signs of toxicity until the highest dose at 24 hours. This was 10 times the amount you would use clinically.”

Betamethasone and methyl prednisolone showed toxicity at 2 hours, he said.

Smaller instrumentation improving vitrectomy

The use of 23- and 25-gauge instrumentation for vitrectomy improves patient comfort and postoperative recovery.

At a scientific session at the Euretina meeting, Stanley Chang, MD, said the advantages of 23- and 25-gauge instrumentation and the improvements made to those vitrectomy systems outweigh their disadvantages.

“I believe 25-gauge primarily offers improvement in comfort and postop recovery,” he said. “The disadvantages are that the cutter is less efficient and there’s an increased cost.”

Among the improvements to the smaller-gauge systems have been the introduction of a xenon light source for improved visualization and of disposable 25-gauge forceps that give the surgeon a larger platform for a firm grasp of tissue, Dr. Chang said.

“I also prefer the new contact lens system, which floats on a layer of Healon GV,” Dr. Chang said. “Earlier versions of 25-gauge systems weren’t very satisfactory, but [with the new system] now we’re using them in straightforward macular surgeries. I use it in 35% of my surgeries.”

Regarding the 23-gauge vitreous cutter, Dr. Chang said, a major advance was the relocation of the port closer to the tip.

“It allows us to get into smaller openings and cling to the membrane,” he said. “The smaller port closer to the tip will allow us to use smaller instruments.”

The 23-gauge also offers improved stiffness compared to the 25-gauge instrumentation, and its flow rates are similar to standard 20-gauge vitrectors, he said.

“In the future I believe we’ll be using 25 gauge for macular surgery and easier cases, and 23 gauge will eventually replace the 25. The improvement of cutters will reduce the need for other instruments,” Dr. Chang said.

Supplementation may improve vision in people with dry AMD

Regular consumption of high-dose antioxidants seems to offer a visual benefit to some patients with dry age-related macular degeneration, said Stuart Richer, OD, PhD, FAAO, who presented results of a clinical trial of daily supplementation with 6 mg to 10 mg of lutein, along with zeaxanthine. He said the supplement could help 100,000 people with dry AMD in America alone.

This recent trial confirmed results from earlier studies that showed “improved visual function in most AMD patients” who were taking the lutein supplement, Dr. Richer said.

“The objective of the Lutein Antioxidant Supplementation Trial was to determine whether nutritional supplementation with the carotenoid lutein or lutein together with antioxidants, vitamins and minerals improves visual function and symptoms in atrophic AMD,” Dr. Richer said.

The study was a prospective, randomized, 12-month trial of 90 patients with atrophic AMD, Dr. Richer said. Patients were separated into three groups, one receiving 10 mg lutein supplementation alone, a second receiving a lutein formulation with broad-spectrum antioxidants and vitamin supplement called Ocupower, and a third receiving a placebo.

At 12 months, visual improvement was 36% in the lutein group and 43% in the lutein and antioxidants group.

“Visual function improved with lutein alone or lutein together with other nutrients in that small and brief study of mid-western U.S. male subjects with atrophic macular degeneration,” Dr. Richer said.

Remembering risk factors for melanoma can save lives

Recalling the basic risk factors for uveal melanoma one learned as a resident may help save lives, according to Carol S.L. Shields, MD. She reminded attendees how to identify those at risk for developing ocular melanoma during the Kreissig Award Lecture she delivered here at the Euretina meeting.

“We have to remember there are five important risk factors, which can be memorized using the simple pneumonic TFSOM -- To Find Small Ocular Melanoma,” Dr. Shields said.

‘T’ stands for thickness, ‘S’ for symptoms, ‘F’ for fluid, ‘O’ for orange pigment and ‘M’ for margin at the optic disc, she explained.

Dr. Shields said patients with nevi who have three or more of those risk factors have a 50% risk of developing melanoma.

“Don’t mistake these small melanomas for nevi,” Dr. Shields said. “Remember the risk factors and you may save a life.”

She noted that nevus growths alone result in an eightfold increased risk for developing metastatic disease.

Dr. Shields touched on the six important choroidal tumors: nevus, melanoma, metastasis, hemangioma, osteoma and retinoblastoma.

As for the risk of ocular nevi developing into melanoma, Dr. Shields said that – while there is conflicting literature on the subject – a study published last month by Tero Kivelä, MD, found that the lifetime risk of someone developing melanoma is estimated at 0.8%.

“This is why it is important for doctors to know the risk factors, she said.

For more information:

• David W. Mullin is Executive Editor of OSN Europe/Asia-Pacific Edition.