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A Preview of ARVO
Research abstracts point to increased innovation.
BY JERRY HELZNER, SENIOR EDITOR

Ophthalmologists are quickly gaining the reputation as the mavericks of medicine because of their willingness to use drugs and devices off-label in the interests of improving patient care. Their thirst for innovation and investigation is reflected in the research abstracts for the upcoming Association for Research in Vision and Ophthalmology (ARVO) meeting, scheduled to begin April 30.

With literally thousands of excellent research papers and posters due to be presented at ARVO, Ophthalmology Management editors have looked through hundreds of abstracts in an effort to highlight 11 that are particularly timely or compelling. This was no easy task, given the
overall high quality of this year's research. Clearly, areas of current interest include innovative use of presbyopia-
correcting lenses, comparisons of refractive surgery procedures, ideas for dealing with so-called floppy-iris syndrome in cataract surgery and progress in treatments for wet AMD. This article will highlight research in those areas, plus other research of interest to ophthalmologists. 

Several research papers discuss the use of Avastin to treat retinal diseases.

Visual Function in Multifocals

Frank A. Bucci, M.D., of Wilkes Barre, Pa., measured near and intermediate visual function in cataract and refractive lens exchange (RLE) patients receiving multifocal lenses. One group of 56 patients received bilateral ReSTOR (Alcon, Fort Worth, Texas), while another group of 30 patients received the ReZoom (Advanced Medical Optics, Santa Ana, Calif.) in the nondominant eye and the ReSTOR lens in the dominant eye.

Near vision was not a source of complaints in either group. However, Dr. Bucci found that 13 of the 56 patients who received bilateral ReSTOR volunteered complaints concerning intermediate vision. None of the 30 patients who received ReZoom and ReSTOR complained about intermediate vision. Of the 13 patients who complained about intermediate vision with bilateral ReSTOR, 10 were RLE patients and all were under 60 years of age.

Dr. Bucci concluded the combination of ReZoom and ReSTOR "appears to effectively mitigate voluntary intermediate vision complaints" that were observed in bilateral ReSTOR patients. He also concluded that the probability of intermediate vision complaints in patients receiving bilateral ReSTOR appears to increase with decreasing age, and is greatest in RLE patients under the age of 60.

NSAID Use and Multifocals

Eric D. Donnenfeld, M.D., North Rockville, N.Y., Kerry Solomon, M.D., Charleston, S.C., and Y. Ralph Chu, M.D., Edina, Minn., evaluated the effect of a topical NSAID on visual quality for patients who received multifocal IOLs.

They evaluated the effect of ketorolac tromethamine 0.4% (Acular LS, Allergan) four times a day for 3 days preop and 3 weeks postop vs. placebo in 50 patients bilaterally implanted with the ReSTOR IOL. Comprehensive measurements were taken at 2 weeks and following the second-eye implantation. Patients also filled out lifestyle and vision questionnaires following second-eye implantation.

At 2 weeks following second-eye implantation, patients receiving the NSAID had statistically significant better UCVA, BCVA and contrast sensitivity than the placebo group. The questionnaire responses supported greater patient satisfaction in the group receiving the NSAID. The researchers concluded that preoperative and postoperative use of the NSAID significantly improved visual outcomes in patients bilaterally implanted with the ReSTOR IOL.

Aspheric IOL vs. Standard IOL

A study comparing visual results of flaps cut by the Hansatome microkeratome and IntraLase showed only minor differences.

A team of researchers from Centre hospitalo-universitaire, Besancon, France, conducted a prospective study to compare quality of vision outcomes in 40 patients following cataract surgery. Twenty patients received bilateral implantation of the Alcon Aspheric IOL (SW60AT) while the other 20 were bilaterally implanted with the Alcon standard (SN60AT).

No surgery complications were noted in either group and, as expected, visual acuity improved in both groups. However, a statistically significant difference was found for the Z400 aberration, with an RMS=0,01 with SW60AT vs. an RMS=0,15 with SN60AT. There was no statistically significant difference in contrast between the two lenses.

The researchers concluded that conventional IOLs produce a positive spherical aberration because of their convex anterior face, whereas aspheric IOLs have the same power over the entire face of the lens and do not induce spherical aberration. Thus, the aspheric lens produces a slightly better quality of vision than the standard lens.

LASEK vs. LASIK

In what the researchers termed the largest comparative study to date in the literature, a team of ophthalmologists from the U.S. Air Force Warfighter Refractive Surgery Center, Lackland Air Force Base, San Antonio, Texas, performed LASIK on 324 myopic patients with an average manifest spherical equivalent of -4.26 D and LASEK on 331 myopic patients with an average manifest spherical equivalent of -4.69 D. The VISX Star laser platform (Advanced Medical Optics, Santa Ana, Calif.) was used for all procedures.

Patients were followed for 12 months. At the end of this period, the LASEK group had an average UCVA of 20/19.3 and the LASIK group had an average UCVA of 20/20.6. However, the LASIK group had average BSCVA of 20/16.5 and the LASEK group had average BSCVA of 20/17.6.

The complication rate was 0 for the LASEK group. The LASIK group had two patients who required additional treatment for diffuse lamellar keratitis.

The researchers concluded that both types of surgeries are attractive options for the correction of myopia.

IntraLase vs. Microkeratome

Sanjay V. Patel, M.D. and a team from the Mayo Clinic in Rochester, Minn., performed LASIK for myopia or myopic astigmatism on 20 patients. For each patient, the flap for one eye was cut with a Hansatome microkeratome (Bausch & Lomb, Rochester, N.Y.) and the flap for the second eye was cut with the IntraLase FS (IntraLase Corp., Irvine, Calif.).

Visual results were measured comprehensively at 1, 3 and 6 months following surgery. Patients were also asked if they preferred the vision in either eye.

Researchers found corneal backscatter higher in the IntraLase eye at 6 months, but no difference in high-contrast visual acuity and contrast sensitivity. At 3 months following surgery, seven patients preferred the microkeratome eye, five patients preferred the IntraLase eye and eight had no preference. Researchers concluded that there was no significant difference in vision perceived by patients between the two flap-cutting methods.

Atropine for IFIS

In an interesting small study, Rick E. Bendel, M.D., of the Mayo Clinic, Jacksonville, Fla., was confronted with two cataract surgery patients who had not revealed they were taking Flomax (Boehringer-Ingelheim) prior to surgery. Flomax is commonly prescribed to facilitate urine flow in patients with enlarged prostate glands.

Flomax use can cause Intraoperative Floppy Iris Syndrome (IFIS) in cataract surgery patients, which usually requires the use of iris retractors, pupil-expansion rings or a viscoelastic technique to complete the surgery.

When IFIS suddenly presented in the first eye of each patient, Dr. Bendel used iris retractors to complete the surgery. For the second eye, both patients were treated with atropine 1% 10 days prior to surgery in an attempt to stabilize the iris.

Dr. Bendel reported that the second surgeries in both patients were completed without incident and without the use of iris retractors. Dilation remained greater than 4 mm.

The research concluded that the use of atropine may reduce surgical difficulty and save time and expense for patients at-risk for IFIS.

Detecting Glaucoma Damage

A team of researchers from Hospital Miguel Servet, Zaragoza, Spain, tested the HRT II (Heidelberg Instrument, Vista, Calif.) the Stratus OCT (Carl Zeiss Meditec, Dublin, Calif.) and the GDxVCC (Carl Zeiss Meditec) to determine how well these three instruments could detect structural differences between a healthy eye and a glaucomatous eye. The study involved 66 healthy subjects along with 74 already-diagnosed glaucomatous patients. All of the subjects underwent complete ophthalmic examinations, including HRT II, OCT and GDxVCC evaluations.

The researchers concluded that structural parameters assessed by the devices are useful to discriminate glaucomatous damage, showing no significant difference among the best parameters of HRT II, OCT or GDxVCC.

IOP-Lowering Efficacy

A combined team from Alcon Research and the Little Rock Eye Clinic, Little Rock, Ark., conducted a study of 156 patients with open-angle glaucoma or ocular hypertension to assess the IOP-lowering efficacy of the investigational travaprost 0.004%/timolol 0.5% (Trav/Tim) fixed combination (Alcon) vs. the concomitant administration of Xalatan (Pfizer) and Timolol 0.5% (Xal/Tim)

Patients dosing with Xal/Tim for at least 30 days and with IOP lower than 18 mm Hg at the screening visit continued dosing with open-label Xalatan (PM) and Timolol (AM) once-daily in both eyes for 30 days prior to an examination. Patients with IOPs that remained lower than 18 mmHg at the examination were randomized to receive either Trav/Tim (AM) and placebo (PM) or Xalatan (AM) and Timolol (PM). IOP was then assessed at week 2, week 6 and month 3.

Researchers found that up to 92% of patients in the Trav/Tim group and up to 88% of the patients in the Xal/Tim group maintained clinically relevant IOP response with IOPs lower than 18 mm Hg. ocular hyperemia reported for both groups was similar, 2.5% for Trav/Tim and 2.6% for Xal/Tim. No patients left the study due to adverse events.

The researchers concluded that Trav/Tim fixed combination provides continued adequate IOP control in patients who were previously well-controlled on the unfixed combination Zal/Tim. They also concluded that once-daily dosing likely increases patient compliance.

Avastin/Macugen in Combination

In one of the most timely papers, Mark S. Hughes, M.D., and Delia N. Sang, M.D., Ophthalmic Consultants of Boston and Harvard Medical School, treated five patients with a cross-section of subtypes of wet AMD and a broad range of vision with off-label bevacizumab (Avastin, Genentech) followed by pegaptanib sodium (Macugen, OSI/Eyetech, Pfizer) administered according to label.

The researchers found that patients treated intravitreally with the pan-VEGF Avastin and the selective VEGF blockade Macugen combination demonstrated clinical meaningful responses as determined by a combined assessment of visual acuity (VA), optical coherence tomography (OCT) and flourescein angiography.

The researchers determined that the Avastin/Macugen combination may offer "clinically meaningful outcomes and acceptable safety." They suggested further trials.

Avastin in Diabetic Retinopathy

California Retina Consultants, Santa Barbara, Calif., and Retina Consultants, Sacramento, Calif., conducted a two-practice retrospective study that evaluated the effect of intravitreal Avastin on proliferative diabetic retinopathy (PDR). A total of 30 eyes of 26 patients were evaluated. Patients had been dosed at levels ranging from 12.5 μg to 1.25 mg.

All patients demonstrated reduction or absence of angiographic neovascular leakage after injection, sometimes within 1 day. No significant ocular or systemic side effects were observed. In several patients who received the highest dose (1.25 mg), a "subtle reduction" in leakage was observed in the fellow, untreated eye.

The researchers, led by Robert L. Avery, M.D., concluded that intravitreal Avastin can cause at least short-term regression of retinal and iris neovascularization secondary to PDR. However, observation of biologic effects at 1/100th of the standard dose and effects in the untreated eye "raise concerns of possible systemic effects of this potent agent."

Implantable Miniature Telescope

Henry L. Hudson, M.D., Retina Centers, P.C., Tucson, Ariz., evaluated the safety and efficacy of the Implantable Miniature Telescope (VisionCare Ophthalmic Technologies, Saratoga, Calif.) in 206 patients with severe vision loss due to the effects of AMD. The average age of the patients was 76 and baseline BCVA was 20/316 at distance and 20/250 at near. Patients were implanted monocularly.

At 1-year post-implant, mean BCVA in the implanted eye improved 3.5 lines at distance and 3.2 lines at near from baseline measurements. Patients reported improvement in all subscales of activities of daily life.

During the implantation procedure there were two choroidal hemorrhages and one device dropped into the vitreous. Postoperatively, explants were required in three eyes, two because of device failure and one due to patient dissatisfaction.