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Is
the demand for laser-based refractive surgery at its limit or will
it continue to grow? Will improved lenticular methods eventually
replace Lasik? Sean Henahan asks the experts.
GERMAN surgeon Burkhard Dick MD predicted that excimer laser corneal ablation would continue to be the most frequently performed refractive procedure in this decade. The immediate future will involve exploring wavefront technology to optimise visual results and minimise complications. He notes that, until recently, achieving an uncorrected visual acuity of 20/20 after refractive surgery was considered a success. But it is now clear that 20/20 does not represent perfect vision because many young healthy adults have visual acuities of 20/15 to 20/12. Moreover, a 20/20 result may not reflect the image degradation that can occur after conventional laser treatment. “We can expect to see a number of advances in laser refractive surgery. First, we can expect to provide a higher quality of vision with less glare and halo effects. Correcting vision beyond 20/20 is already becoming a reality. Finally, we will be able to offer correction of refractive errors and aberrations in eyes that previously underwent less-than-optimal refractive procedures - the correction of irregular astigmatism, for example,” Dr Dick told EuroTimes. On a practical level, he predicted that laser technology would continue to improve, along with more compact machines, homogeneous beam profile, lower maintenance costs, accurate eye tracking and customised ablation with optimised ablation profiles for standard treatments. “Wavefront technology in conjunction with corneal topography will not revolutionise refractive surgery but will provide an additional useful tool for achieving improved surgical results. The exaggerated pronouncements in previous years about wavefront-guided ablations will be replaced by realistic assessments and goals.” Looking further ahead, Dr Dick said a better understanding of the biological response of the cornea to laser treatment might allow modulation of the wound healing response for more precise correction. He observed that it is also possible in the longer term that technological progress coupled with economic factors might cause a shift towards lenticular refractive surgery rather than corneal surgery. “The closer we reach the excellence of some of the corneal procedures, the more possible it is that lenticular surgery may even overcome and bypass some of the corneal procedures we now think of as state of the art.” Jorge Alió MD, PhD concurred that improvement in Lasik treatment algorithms, including the correction of high order aberrations, would improve patient outcomes. He predicted that technological improvements would lead to expanding applications for complementary approaches to refractive surgery. “There is indeed a need to expand indications of refractive surgery. In my opinion, additive surgery will have an important place in our future. Additive surgery will be available both with human corneal material and biomaterials. I also expect that refractive surgery will be combined with other corneal refractive procedures, such as deep anterior or posterior lamellar keratoplasty.” In the short term, Dr Alió believes that the demand for Lasik in Europe is stable and will remain so. He predicted that the demand for the procedure will be influenced by the economic situation of the region. “The big boom we had some years ago has passed. Most of those who compulsively demanded refractive surgery have undergone surgery. The demands of patients now are much more rational, less influenced by publicity and commercial development of laser centres and more clinically rather than commercially oriented. “I do not foresee a big role for the commercial development of Lasik centres. There is no question that Lasik now is a market issue and will follow in some degree the laws of the market.” US surgeon Douglas Koch MD expects to see continued growth in demand for refractive surgical procedures, both corneal and lenticular. He predicted that growth in Lasik would occur as wavefront technology is introduced and further improved. “In the next five years, we will develop greater accuracy in both the diagnostic and therapeutic realms. Diagnostically, we will become much more precise in quantifying and characterising ocular aberrations. “This will occur through improvement in aberrometers and in the methodology for interpreting data from them. Surgical accuracy will continue to improve as we gain additional knowledge about tissue interaction and as laser delivery systems improve through improved centration and tracking mechanisms.” Nonetheless, Dr Koch also believes lenticular surgery will become increasingly popular in the presbyopic patients as improved multifocal IOL designs are introduced. Lenticular surgery will also benefit from the introduction of technology such as implantable devices that release antibiotics, thereby minimising the risk of endophthalmitis. The incidence of postoperative cystoid macular oedema will also be reduced by the release of corticosteroids. This growth will be augmented by continued improvement in cataract surgical technology, ultimately leading to the removal of cataracts through a tiny capsulorhexis. Current President of the ASCRS, Marguerite McDonald MD, also believes that wavefront-guided excimer laser surgery will continue to have a key place in treating myopia and higher degrees of hyperopia. She predicts that lenticular approaches, including refractive lens exchange and phakic IOLs will gain market share, representing up to a third of the total refractive cases. Dr McDonald is currently conducting ongoing studies with the recently FDA-approved conductive keratoplasty (CK) procedure. She predicts that CK will become very popular for the treatment of hyperopia and presbyopia because it is quick, safe and effective. “The refractive market has been somewhat moribund, but CK is helping to revive it. This procedure is bringing in an older, more risk-averse and affluent patient who is less affected by the downturn in the economy. They like the bladeless, laser-less aspect of CK. This in turn is bringing in more laser patients, as the children and younger work associates of these happy patients come into the office.” Philippe Sourdille MD, Director of the Sourdille Eye Clinic in Nantes, France also believes Lasik and Lasek will account for a significant amount of refractive operations for some time to come. He predicted that refractive implants would play an increasing role, with indications for both ametropia and presbyopia. He expects corneal rings will continue to be used in special situations such as keratoconus but does not expect corneal inlays or intra-scleral surgery with segments or incisions will stand the test of time. One of the most significant improvements will have to be in corneal tissue healing control. Less aggressive laser treatments with femtosecond lasers are likely to replace all other lasers approaches, Dr Sourdille said. And he advised that we should be more more precise in our preoperative and postoperative evaluations. The development of refined ultrasonography, and consecutive investments, will be very helpful, he said. “The refractive area will be influenced by legal problems. We can expect to see more lawsuits, more regulation and good practice rules. This will change the current scene, especially in Europe. Communication with the patient about refractive surgery will assume growing importance and we will have to become really professional. “Our preoperative and postoperative evaluations will be more and more important and sophisticated. Investments on the evaluation side will have to be a very significant part of any refractive surgery budget,” Dr Sourdille said. Marie-José Tassignon MD, President-elect of the ESCRS, stresses that the future of ophthalmic surgery also depends on governments that understand the importance of the field and are ready to support ongoing research. “The 21st century is a new era in ophthalmology. Progress in refractive surgery is based on the ongoing progress and development of new technologies to better understand visual function. We are no longer limited to only the monitoring of ocular transparency and detection of illness or recognition of ocular pathology. Now we are gaining a better understanding of the quality of vision.” She said that ophthalmology should no longer be an isolated discipline in medicine, but rather form a broad coalition with related fields such as physics. Governmental financial support is the key for that dramatic evolution to continue, she stressed. “We are currently in a very fragile economic situation and in a new type of war. How far this war will go remains unknown. In case of economic recession, the government will reduce financial input in research and this is a real threat to the field.” Burkhard
Dick MD, University of Mainz, Germany |
