AAO Highlights: Lasers for Cataract Surgery, Laser Vision Correction Trends, and More
November 10, 2009
In addition to the highlights previously posted by Dr. Dominque Brooks on this blog, I have obtained some additional interesting excerpts of several talks that were presented during the meetings.
The following excerpts are taken from the Academy Live emails sent out to AAO members during the meetings.
Here are the highlights:
October 23, 2009
Laser technology for cataract surgery
Femtosecond laser technology first captured the attention of refractive surgeons in its role as an alternative to the microkeratome blades used in LASIK. Now, this same technology may change the way cataract surgeons perform anterior capsulotomies. Several companies, including LenSx Lasers, LensAR and OptiMedica, are working on laser technology as an alternative to manual capsulorhexis.
Louis D. Nichamin, MD, discussed initial results from a clinical trial at the APEC Hospital in Mexico City using the LensAR laser system to compare laser capsulotomy to manual capsulorhexis. Fifty-nine eyes of 59 patients underwent the laser capsulotomy, and a control group of 26 contralateral eyes underwent manual capsulorhexis. The mean difference between attempted and achieved capsulotomy diameter was 0.183 + 0.246 mm for the laser group and 0.456 + 0.735 mm for the manual group. Dr. Nichamin said these results indicate laser capsulotomy provides a more accurate and repeatable capsular opening with a more regular shape compared with manual capsulorhexis.
LenSx Lasers has received FDA clearance of its femtosecond laser for anterior capsulotomy during cataract surgery, and Dr. Nichamin said he predicts LensAR’s technology will start human trials in the United States in 2010.
“Without a doubt, laser technology for cataract surgery is a paradigm change for us,” he said. “It has potential not only in creating a perfectly centered and sized capsulotomy, but also making penetrating and nonpenetrating incisions, and in its ability to liquefy the lens.”
The only downside he sees is the cost of the technology. “In this tumultuous economic milieu, where everyone is so concerned on how to pay for medicine, we need to create a delivery model that makes sense,” Dr. Nichamin said. “But this technology is positioned to play an extraordinary role in lens-based surgical operations.”
Dr. Nichamin is a consultant for LensAR Lens Systems.
(Also see Dr. Weitzner’s posting on this subject: Will Femtosecond Laser Technology Revolutionize Cataract Sugery?)
When money and medicine work for a common good
Compelling progress in medical research is often possible only with muscular investment backing, and both of these found enthusiastic supporters at the Ophthalmology Innovation Summit, held yesterday (Thursday) in San Francisco’s historic Palace Hotel. Cochaired by Emmett T. Cunningham Jr., MD, PhD, MPH, and William J. Link, PhD, the Summit brought together over 400 ophthalmologists, researchers, industry leaders and well-informed investors to discuss the latest ideas in ophthalmic drugs and devices—and the financial resources that could bring them to market.
The Summit—which is one of many satellite events this week—began with ophthalmic start-up developers presenting projects in various stages of development, including:
* a fluid-filled IOL that mimics natural accommodation,
* prokinase inhibitors to treat glaucoma,
* antisense agents and eotaxin inhibitors for diabetic macular edema,
* rapamycin-derived mTOR inhibitors for uveitis, AMD and diabetic eye disease,
* epimacular brachytherapy—as well as newly configured external beam radiotherapy—for AMD,
* ciliary neurotrophic factor for dry AMD,
* an antibacterial film to ensure watertight wounds at the close of surgeries,
* a retinal prosthetic platform using a scanning-dependent external camera attached to a retina-embedded electrode.
Executives from larger companies weighed in with criteria that, for them, makes a new idea worthy of investment. These included proof of concept in animal studies as well as some characteristics that will distinguish the drug or device from competitors’ products. None of the individual investors in the audience thought that a slow economy was a bad time, per se, to make investments, and, in fact, several commented that putting assets on the table now will enhance their potential returns when capital starts flowing again.
Wrapping up the Summit, Richard L. Lindstrom, MD, and Mark S. Blumenkranz, MD, each offered thoughts on what the next five years hold for ophthalmology. Dr. Lindstrom said that glaucoma surgeries may become a safe and more effective first-line alternative to medical management in patients who are regularly non-adherent with, or whose disease is refractory to, topical therapies. He also suggested that efforts to prevent cataractogenesis and presbyopia may someday preempt efforts to treat them.
Dr. Blumenkranz said that ophthalmologists are learning what oncologists discovered years ago—combination therapy is often superior to monotherapy. He also noted that virtually all retinal diseases conform to one of four avenues of pathogenesis, and that all four of those are in some part VEGF-dependent.
Dr. Cunningham hopes to make the Summit an annual event.
[Editors note: This meeting was held on October 22nd, and featured 25 startup and early technology company presentations, half on devices, and the remainder on pharmaceutical treatments.]
October 24, 2009
Intraoperative wavefront aberrometer provides real-time data
One of the running themes during Refractive Surgery Subspecialty Day has been the low tolerance for small refractive errors in premium intraocular lens patients, with residual astigmatism a particular challenge. Eric D. Donnenfeld, MD, discussed the role of intraoperative limbal relaxing incisions (LRIs) in addressing this concern.
Karl G. Stonecipher, MD, covered the effectiveness of toric lenses for astigmatism, stressing the need for precise intraoperative identification of the correct lens orientation. Small errors in alignment and stability can reduce effectiveness.
Both speakers pointed to the ORange Intraoperative Wavefront Aberrometer, which can guide surgeon decision-making in real time. The device, which fits on the bottom of the surgical microscope, allows the surgeon to take on-demand wavefront images of the eye, and provides refraction data.
“This technology allows for confirmation of refractive outcomes before leaving the OR,” noted William B. Trattler, MD, who is one of 12 phase 3 investigators. “This device is particularly useful for determining the proper IOL power for a post-refractive patient, fine-tuning the toric IOL axis placement, as well as optimizing LRIs. Indeed, if the LRI is undercorrected, the surgeon is alerted and can perform intraoperative enhancements.”
Drs. Donnenfeld and Trattler are consultants for WaveTec Vision Systems. Dr Stonecipher does not have an interest in WaveTec.
ISRS/AAO survey: Laser vision correction volume down by 15 percent in 2009
The annual survey of ISRS/AAO members showed overall laser vision correction volume was down 15 percent among its members, said Richard J. Duffey, MD, who conducts the annual survey Trends in Refractive Surgery in the United States.
This year’s survey was conducted online for the first time and received a response rate of 19.4 percent.
Among the highlights:
* About 25 percent of refractive surgeons have had some form of modern refractive correction, three or four times greater than that of the general population. The rate is even higher among family members: 36 percent of spouses, 19 percent of children and 57 percent of siblings.
* Femtosecond laser use outstripped microkeratome use for the first time in 2009, with 52 percent of surgeons now using a femtosecond laser.
* VISX excimer laser still dominates the laser market with a 58 percent share, but the WaveLight laser system is on the rise with 28 percent of the market.
* Among premium IOLs, the ReStor is still the most popular, implanted in 9 percent of cataract surgery; the Crystalens, 6 percent, and the Tecnis, 4 percent.
Learn more about Dr. Duffey’s study online www.duffeylaser.com
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