Eyeworld

EW NEWS & OPINION 21 ported. "Measuring changes in the radius of curvature of 3 mm/mm Hg, the contact lens sensor gave a highly linear and reproducible output over an IOP range of 15–30 mm Hg in enucleated pig eyes." Intersecting with theragnostics, nanotechnology is beginning to pro- vide customized diagnosis and ther- apy for patients, right down to the amount and location of therapy. One early innovation is a biosensor DNA tied to a magnetic nanoparti- cle. "The antioxidant biosensor could provide a means for clinicians to identify patients likely to need therapy (e.g., babies with retinopa- thy of prematurity who will need laser photocoagulation or other treatment) at a time before clinical manifestations of severe disease are evident," Dr. Zarbin reported. It's also possible to go a step fur- ther in the creation of a diagnostic- therapeutic device that allows any cells that take up the nanoparticle to "treat themselves" in the event of oxidative damage, Dr. Zarbin sug- gested. At the moment, however, nanoparticles have more widespread use as a deliverer of drugs, peptides, and genes. "Nanoparticles are colloidal carrier systems that can improve the efficacy of drug delivery by over- coming diffusion barriers, permit- ting reduced dosing (through more efficient tissue targeting), as well as allowing sustained delivery," Dr. Zarbin noted. "Basic fibroblast growth factor delivery by means of intravitreal nanoparticles has provided sus- tained retinal rescue in Royal Col- lege of Surgeons rats," Dr. Zarbin reported. "Biodegradable (poly)lac- tic-co-glycolic acid (PLGA) micros- pheres loaded with intravitreal glial-derived neurotrophic factor provide sustained ganglion cell pro- tection in rodent models of glau- coma. PLGA has been approved for human use by the U.S. Food and Drug Administration." Molecules are also being used as machines—a fact that will be helpful for prosthetics. "In conditions such as RP, for example, the photoreceptors degen- erate," Dr. Zarbin said. "Despite the fact that rewiring of inner retinal cir- cuits and inner retinal neuronal de- generation occur in association with this degeneration, it is possible to create visually useful percepts by stimulating RGC electrically. Using light-sensitive ion channels rather than electrodes to stimulate RGC provides an alternative approach to retinal cell stimulation. Induced light sensitivity provides the capac- ity for noninvasive neuronal stimu- lation with high spatial resolution." Finally, the application of nan- otechnology in regenerative medi- cine will likely be helpful in ophthalmology as well. "A further advance in regenera- tive ophthalmic medicine would be to replace damaged or dead retinal neurons in patients with chronic retinal detachment, RP, AMD, and allied diseases," noted Dr. Zarbin, al- though he also suggested that neu- ronal replacement is a "nascent" field. "Obstacles to the incorporation of nanotechnology remain: safe manufacturing techniques and unin- tended biological consequences of nanomaterial use," Dr. Zarbin con- cluded. "These obstacles are not in- surmountable, and revolutionary treatments for ophthalmic diseases are expected to result from this bur- geoning field." As an ophthalmologist, Bjorn Johansson, M.D., Linkoping Univer- sity Hospital, Linkoping, Sweden, said that nanotechnology is an in- teresting field, and it complements the direction of ophthalmology be- coming more minimally invasive. "There is always a drive to get smaller," Dr. Johansson said, citing smaller incisions as one example. He seemed particularly inter- ested in theragnostics and the development of "a pharmacological activity at the place where you want it to be." "Instead of injecting the eye, let nanotechnology carry the steroid to the place where we need the ac- tion," Dr. Johansson suggested. He also hopes that nanotechnology paves the way to ridding therapy of side effects and helps modify the surfaces of IOLs. EW Editors' note: Dr. Zarbin has no finan- cial interests related to this study. Dr. Johansson has no financial interests re- lated to his comments. Contact information Johansson: bjorn.johansson@lio.se Zarbin: zarbin@umdnj.edu Dr. Van Meter said it is impor- tant for ophthalmologists to open their wallets to their organizations and PACs. "You have to pay to play," he said. "You need to invest in your PAC. We didn't give enough money to state legislators and we didn't have enough lobbyists paying atten- tion, and look what happened." Even more important than money is time, Dr. Bakewell said. "Ophthalmologists have to be- come politically active because the optometrists use scope of practice as nothing more than a political process," he said. "It incenses me. There is a way that optometrists can become surgeons. It's called medical school and ophthalmic residency, but that's too hard. It's easier just to buy the legislature. It's sad for the patients because those are the folks who are going to be hurt by this measure." The best defense against further scope of practice legislation is a good offense, Dr. Bakewell said. That in- cludes investing money and, more importantly, time. "It's not like you give your legis- lators money and that's a one-time deal," he said. "You have to get to know your legislator and go out to lunch, invite him or her to your of- fice. You have to develop a relation- ship so that the legislator trusts you. When these issues come up, not only have we supported the legisla- tors financially like the optometrists have, but we were there to give them the medical viewpoint of in- creased scope of practice for optome- try." Organized ophthalmology needs to do a better job of pointing out the distinction between the two professions, Dr. Van Meter said. "There are a number of people in the state who probably don't know the difference between an op- tometrist and an ophthalmologist," he said. "The American Academy of Ophthalmology did a poll and showed that 70% of people think optometrists went to medical school, and they didn't." In Oklahoma, Gov. Mary Fallin signed House Bill 1044 into law in April. That new law requires legisla- tive approval of rule changes on fee increases and scope of practice by the optometry board there. A similar independent optometric board now exists in Kentucky and will solely de- cide scope of practice for the profes- sion. Dr. Van Meter noted that the Kentucky bill was nearly identical to the Oklahoma bill in the way it was written, even down to the punctua- tion. He said, "Maybe Kentucky will need to enact a restraint of privilege bill similar to the one Oklahoma has just passed. Kentucky might have to follow Oklahoma's example once again." EW Contact information Bakewell: 520-293-6740, eyemanaz@aol.com Van Meter: 859-275-4001, wsvanmeter@aol.com Lessons continued from page 18 EyeWorld factoid Optometrists are allowed to treat and manage glaucoma in 49 states in the U.S. Massachusetts is the only state in which optometrists cannot prescribe medica- tions used in the therapy of glaucoma Source: The Glaucoma Foundation June 2011

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