March 22, 2010

US Military The Vanguard in Refractive Surgery Research and Implementation

Category: LASIK

More than 312,000 laser refractive procedures performed in the U.S. Air Force, Army and Navy have provided invaluable insight about laser refractive surgery to both military and civilian communities.

Since the first military laser study began in 1993 and the U.S. Department of Defense adopted laser refractive surgery in 2000, military laser refractive cases have demonstrated safety, efficacy and excellent visual results when performed in appropriate patients.

Military refractive cases have also provided accurate and large sample data that can be extrapolated to the general population.

“The studies that we perform here at the Naval Medical Center San Diego are viewed by civilian ophthalmologists all over the world as a benchmark of refractive surgery research because the studies are unbiased, they’re fair, they’re balanced,” U.S. Navy Capt. David J. Tanzer, MD, said. “We’re looking at safety and efficacy of [military] war fighters, so we want to ensure that these procedures are safe. … The extrapolation of the data that we accumulate here influences how civilian surgeons perform refractive surgery all over the world.”

U.S. Navy Capt. David J. Tanzer, MD, performing LASIK on a patient, says that unbiased military studies of the procedure are a benchmark of refractive surgery research.

Known as a “force enhancer” or “force extender” in military parlance, refractive surgery is considered a life-saving procedure in all branches of the U.S. military. It has also helped to alter the paradigm of military medicine, according to Steven C. Schallhorn, MD.

“Refractive surgery has been revolutionary in the military,” Dr. Schallhorn said. “Nothing short of revolutionary, as far as what it can offer active duty members. Put simply, it can enhance battlefield safety and improve the performance of our military personnel.”

Refractive surgery in military

When laser refractive surgery was approved by the U.S. Food and Drug Administration, it was not permitted for enlisting military service members, but a system of waivers now allows for the procedure. The Air Force was the first military branch to waive both PRK and LASIK for all personnel, including LASIK for aviators.

The Navy and Marines Corps waive PRK and LASIK for military personnel, but not for aviators. However, those on active naval flight duty can have successful PRK procedures waived, and LASIK can be performed if service members enroll in the ongoing LASIK aviator study at the Naval Medical Center San Diego.

In the Army, both PRK and LASIK are waived for most service personnel. LASIK is performed in the Army; however, surface ablation, such as PRK and LASEK, is the preferred procedure to be performed on combat-bound soldiers and others in special operations.

Laser refractive surgery for active military personnel is now supported by the Department of Defense and top military commanders. There are six active laser refractive centers in the Air Force, 10 such centers in the Army and seven in the Navy.

Military laser refractive surgery is voluntary and based on FDA guidelines for patient selection. Patients are carefully screened and provided a detailed informed consent before refractive surgery, the same as with civilian populations.

All branches of the military adhere to specific standardized clinical guidelines for screening, examining and performing refractive surgery and following patients postoperatively. Outcomes of numerous clinical trials conducted in the military have served to hone this process to improve the outcomes of treatment performed on military members.

The most common laser procedure performed in all branches of the military is PRK, while LASIK has been gaining in popularity in recent years. In some Army laser refractive centers, up to 30% of procedures are LASIK, and at the Naval Medical Center San Diego, more LASIK procedures are performed than PRK, at a rate of 2-to-1, according to Dr. Tanzer.

Key study results

Quality of vision after refractive surgery was one of the most important factors first examined by military studies, Dr. Schallhorn said. Military research has studied thousands of patients and found excellent results even among large subject sets.

At the Naval Medical Center San Diego alone, more than 45 studies have been conducted, 15 of those with investigational device exemption from the FDA. An ongoing study there is examining 300 aviators on active flight duty — including 100 pilots — who are undergoing wavefront-guided LASIK with a femtosecond laser. So far, 175 aviators have undergone refractive surgery, Dr. Tanzer said, and approximately 50 of those are in control of an aircraft.

The study is examining the safety and efficacy of the procedure for potential approval in naval aviators, he said.

Results have shown that at 2 weeks, all aviators have 20/20 or better uncorrected vision. Of those, 96% are 20/16 and 75% are 20/12.

“The data that we have received thus far from this study is unbelievably good. It’s the best that I’ve ever seen reported or presented anywhere in the world,” Dr. Tanzer said. “Our nearsighted aviators are eligible to return to flight status by 2 weeks following refractive surgery now.”

Military studies have investigated topics such as patient-reported outcomes after surgery, contrast sensitivity, high-altitude conditions and LASIK flap exposure in high wind blasts. Studies that have investigated different laser platforms and technology without bias have also improved outcomes, Dr. Schallhorn said.

The extensive military refractive surgical experience has shown that patient selection is key to best outcomes, Dr. Reilly said. Rigorous preop screening is vital.

In addition, best postoperative results are achieved if patients use eye drops and sunglasses as directed, he said.

“The majority of the military does a lot of surface ablation, and the problems with corneal haze can really be significant if our patients aren’t educated well about how to avoid haze formation,” Dr. Reilly said.

Military results, civilian populations

Military refractive surgery demonstrates how military medicine has helped contribute to the civilian population. Dr. Reilly noted that military medicine developed the yellow fever vaccine, addressed anti-malarial and parasitic infections, and now, with refractive surgery, has changed vision enhancement.

“In the world of refractive surgery, we’ve been really trying to help advance the science and help the whole ophthalmic community understand better what’s the role of refractive surgery and what’s possible with refractive surgery,” he said. “It really is a very synergistic relationship between the military and the civilian community when it comes to refractive surgery.”

Dr. Barnes said that even though PRK is considered a more painful procedure than LASIK, Army personnel have rated pain from the procedure on a scale of 0 to 10 as a “2” at 1 day after surgery. Service members do not have a higher threshold for pain than civilians, Dr. Barnes said, and will tell physicians when they are unhappy with surgical results.

“Soldiers are like a slice of the civilian community as that is where they come from; there are tough people who wouldn’t complain at anything and there are others who seem not to tolerate almost any irritant,” he said.

In addition, almost uniformly, most military patients consider their postoperative refractive results outstanding. While there are those who occasionally complain, he said, “we have not had to discharge anybody from the Army due to a poor result or complication of refractive surgery.”

The nonmilitary community has sought out military commentary on refractive surgery. In 2008, Dr. Tanzer and Dr. Barnes spoke at an FDA Ophthalmic Device Panel meeting that examined the use of LASIK. The panel reviewed topics such as procedure safety and patient satisfaction after there were syndicated reports of patient depression and suicide after LASIK.

Dr. Tanzer presented Navy results and the military perspective on laser refractive surgery, while Dr. Barnes, who had PRK in the military before he became an ophthalmologist, spoke about LASIK and excellent patient satisfaction results. He also presented studies in military populations that have shown refractive surgery is a safe and effective procedure.

“We [military ophthalmologists] make no money if we do no laser cases at all, if we do a thousand laser cases; we make the exact same amount of money. It is of zero dollar interest to us. In fact, our life would be easier for us if we didn’t do it. We’d have less work to do. But our population is so clearly in favor of this, so happy with this and wants this, and says it’s a need for them,” Dr. Barnes said. “It’s pretty strong, being able to say things from that perspective.”

Although the Army mainly performs PRK, he said he appealed to the FDA to not discontinue the use of LASIK for military personnel because of the growing number of LASIK done in their centers.

“These soldiers, these sailors, these marines, these airmen, they are doing jobs that are now more secure,” he said. “This changes their lives. In some cases, it’s a difference between life and death.”– by Erin L. Boyle

References:

  • Hammond MD, Madigan WP Jr, Bower KS. Refractive surgery in the United States Army, 2000-2003. Ophthalmology. 2005;112(2):184-190.
  • Rabin J. Refractive surgery in the military. Tri-Service Vision Conservation and Readiness Program Web site. http://chppm-www.apgea.army.mil/doem/vision/army/RF_surgery/refsurginmil.ppt. Accessed Feb. 24, 2009.
  • Schallhorn SC, Blanton CL, Kaupp SE, et al. Preliminary results of photorefractive keratectomy in active-duty United States Navy personnel. Ophthalmology. 1996;103(1):5-22.
  • Col. Scott D. Barnes, MD, is stationed at Womack Army Medical Center, Fort Bragg, NC 28310. He can be reached at COL Scott Barnes, Dept. of Ophthalmology-WAMC, Fort Bragg, NC 28310; 910-907-7921; e-mail: scott.d.barnes@us.army.mil.
  • Lt. Col. Charles D. Reilly, MD, can be reached at 59 SSS/SGO2E, Wilford Hall USAF Medical Center, Lackland AFB, 2200 Bergquest Drive, Suite 1, San Antonio, TX 78236-5300; 210-292-2010; fax: 210-292-2313; e-mail: charles.reilly@lackland.af.mil.
  • Steven C. Schallhorn, MD, can be reached at scschallhorn@yahoo.com.
  • Capt. David J. Tanzer, MD, can be reached at Naval Medical Center San Diego, 34800 Bob Wilson Drive, San Diego, CA 92135; 619-532-6700; e-mail: david.tanzer@med.navy.mil.

March 8, 2010

Visian Implantable Collamer Lens provides U.S. Bobsled Pilot with the vision to lead his Team to first Olympic Gold in 62 Years.

In a historic moment for the United States bobsled team, Steven Holcomb piloted bobsled USA-1 to the Olympic gold medal in the four-man event, ending a 62-year Olympic medal drought for the American. Holcomb’s heroic mastery of the treacherous track is made even more significant by the fact that not long ago, he had 20/500 vision — “profound visual impairment” caused by keratoconus– that very nearly ended his bobsledding career. Contact lenses could no longer provide the level of visual acuity required for Holcomb to compete. Finally, with the help of U.S. bobsled coach Brian Shimer, he was deemed a good candidate for the Visian ICL. Holcomb said. “I couldn’t wear contacts the day of the surgery, so they literally had to walk me around the room. And then they did it, I got up, and just like that, I was 20/20. It’s incredible. I call it an eye-opening experience.”


September 29, 2009

Selective Laser Trabeculoplasty (SLT)

Glaucoma occurs when there is an increase of fluid production or a decrease in fluid drainage within the front part of the eye. Over time, as the pressure within the eye remains elevated or peaks at different times of the day, the optic nerve fibers are destroyed and peripheral (side) vision is lost. If not treated adequately, an elevated pressure can also cause irreversible loss of central vision.

Aqueous humor flows out of the eye through the Trabecular Meshwork near the outer edge of the iris. Over time, in certain individuals with glaucoma, that trabecular meshwork becomes blocked and the pressure within the eye increases. Treatment of open angle glaucoma is aimed at lowering the pressure within the eye by either decreasing the production of aqueous humor or helping it escape from the eye. There are medications to help with this process as well as surgical treatments.

Selective Laser Trabeculoplasty-SLT does not rely on medicines. Instead, it uses an advanced laser system to target specific melanin containing cells within the Trabecular Meshwork. As a result of SLT, your body’s own healing response helps lower the pressure within your eye.

Laser surgery has become an increasingly popular treatment to control eye pressure prior to consideration of glaucoma filtration surgery or prior to adding several medications to control the intraocular pressure. Selective Laser Trabeculoplasty (SLT) is an advanced form of laser treatment for open-angle glaucoma. SLT uses short pulses of low energy laser light to target melanin-containing cells in a network of tiny drainage channels, within the Trabecular Meshwork. The objective of the surgery is to increase fluid draining out of the eye, reducing the intra-ocular pressure that can cause damage to the optic nerve and loss of vision.

The selective technique is much less traumatic to the eye than the older method called Argon Laser Trabeculoplasty (ALT), which had been the standard laser procedure in the past. ALT can cause tissue destruction and scarring of healthy cells in the Trabecular Meshwork structure. SLT reduces intra-ocular pressure without this risk. SLT can be used to effectively treat some patients who could not benefit from ALT. This includes patients who have already been treated with ALT.

More importantly, this procedure may be used instead of, or in addition to glaucoma medications as a means to control the intraocular eye pressure in many individuals.

SLT is for those:

  • who have been diagnosed with open angle glaucoma
  • whose doctor has determined that SLT is appropriate for controlling their intra-ocular pressure
  • who would rather not have to use any (or additional) medications to control their eye pressure

SLT is:

Safe: SLT is not associated with the side-effects of some medications.

Selective: SLT treats only the specific melanin containing cells in your eye.

Smart: SLT stimulates the body’s natural mechanisms to enhance outflow in the eye.

Sensible: SLT is reimbursed by Medicare and other insurance companies to reduce the costs of medications over time.

What to expect on procedure day:

Your treatment will be performed in your doctor’s office in an examination room equipped with a laser attached to a special microscope, similar to the one used for your eye examinations. SLT does not require a surgery center. Once you have been checked in and settled comfortably, eye drops will be used to numb your eye; no injections or needles are used.

Your doctor will hold up a special lens to your eye which allows him to focus the laser onto the meshwork drain inside your eye. You may see flashes of bright green or red light. The laser selectively targets melanin-containing cells, resulting in increased fluid outflow. You will not feel any pain during the procedure. The entire procedure takes only a few minutes.Your eye pressure will be checked again one to two weeks after your procedure. If there is any soreness, you may use an eye drop for comfort. The full pressure-lowering effect of this procedure may take up to 8 weeks; however, your doctor can oftentimes tell at two weeks if you are a good responder. Usually, there are no activity restrictions following this procedure and you may resume your normal activities immediately.

Realistic Expectations

The effect of the surgery may wear off over several years; however, it may be repeated without ill effects. Serious complications with SLT are extremely rare, but like any surgical procedure, there may be some risks. Going to a specialist experienced in SLT can help minimize the risks and increase the chances of success. Here at Peninsula Laser Eye Medical Group, we specialize in lasers for treating conditions within the eye.

If you and your doctor decide that SLT is an option for you, you will be given additional information about the procedure that will allow you to make an informed decision about whether to proceed. Be sure you have all your questions answered to your satisfaction. If you would like more information about this procedure you can make an appointment or contact the office for additional information.


August 17, 2009

Glaucoma awareness month – don’t get blindsided

Category: Glaucoma

dr-dan-beersMore than 66.8 million people are visually impaired by glaucoma worldwide and the disease has blinded 6.7 million people, according to the National Glaucoma Research, a program of the American Health Assistance Foundation. The foundation is committed to funding research and getting the word out about glaucoma – January is National Glaucoma Awareness Month.

People of all ages – from babies to senior citizens – are at risk for this incurable disease, which is a group of diseases that affect the optic nerve and can cause blindness without any warning or symptoms. It is not curable and any vision lost cannot be regained. Glaucoma is the leading cause of preventable blindness.

The only way to combat glaucoma is to be aware of it, according to ophthalmologist Dr. Dan Beers of the Peninsula Laser Eye Medical Group. Early detection by an ophthalmologist can prevent blindness, he said, adding that he strongly suggests annual eye exams.

Three million Americans have glaucoma, but only half of them know it. “If you wait until you are having problems seeing, it could be too late,” Beers said.

A well-trained ophthalmologist should be able to detect early stages of glaucoma through careful examination of the optic nerve, the bundle of nerve fibers that carries information from the eye to the brain, he said.

Once the disease is detected, its progression can be slowed dramatically through the use of prescription eyedrops or laser procedures that reduce the amount of swelling in the optic nerve.

Beers said if he notices anything unusual about the optic nerve, he immediately uses Heidelberg Retinal Tomography (HRT) for further testing. The HRT is the best instrument available to analyze the optic nerve in three dimensions.

“It takes a three-dimensional view to find early loss in optic nerve tissue,”
Beers said.  For more information, visit www.ahaf.org/glaucoma.


April 26, 2009

The Eyes Have It

Category: LASIK

Two local doctors perform LASIK surgery to correct nearsightedness

Some people may be able to eliminate their need for eyeglasses with a 15-minute laser surgery at Peninsula Eye Physicians and Surgeons in Mountain View.

“Got a minute? Get Lasik!” states a brochure for Drs. Mark Volpicelli and Daniel Beers, who use a laser procedure called LASIK (Laser in-Situ Keratomileusis) to correct certain refractive vision problems.

“We both had (the procedure). He did mine, I did his,” said Volpicelli, a Los Altos resident who graduated from medical school at the University of California at San Diego.

The two doctors met at an ophthalmology conference in 1995 and started practicing together soon after.

The office moved to its current location at 1174 Castro St. three years ago.

Volpicelli and Beers said the capabilities of laser surgery have expanded exponentially in recent years. They can treat nearsightedness, farsightedness and astigmatism. Volpicelli said more than 1,100,000 in the United States have undergone LASIK, and he and Beers see between 500 and 750 patients each year.

“The chance of seeing 20/20 or 20/25 … is about 80 percent,” Beers said. Volpicelli said 98 to 99 percent can pass their driver’s license test, which requires 20/40 vision, without glasses after LASIK.

“The results are so good, there’s a lot of word of mouth,” said Beers, who lives in Mountain View.

Recently Beers performed LASIK on Margie Sanchez, whose husband already had had the procedure. A friend was coming the next day to have LASIK as well.

During her LASIK procedure, Sanchez reclined in a chair while Beers put several sets of drops in her eye. He wore tan socks and no shoes, as the laser is operated with foot pedals. After the eyedrops sank in, Beers had Sanchez focus on a flashing red dot as he used a device called a microkeratome to cut a protective flap in her cornea. There is just a “little pressure sensation, not a sharp pain,” Beers said.

Sanchez looked comfortable as the laser reshaped her cornea, the part of the procedure that allows her to stop needing glasses. After a few minutes, Beers replaced the flap, and Sanchez said things were already in better focus.

About 10 minutes later, Sanchez walked out the door with her husband. He happily told Beers he had recently put on his old glasses but couldn’t see with them since his LASIK procedure.

Volpicelli said results are almost immediate. “Most patients drive to their appointment the next day,” he said.

LASIK costs about $4,800 for two eyes, and usually isn’t covered by insurance, which considers the surgery to be cosmetic. Volpicelli said about 95 percent of patients pay for their own procedure, but Peninsula Eye Physicians offers financing programs.

The cost includes surgery, pre-operation exams, medication, follow-up exams for a year and enhancement procedures if necessary.

“Patients think (their uncorrected vision) is debilitating enough to take care of it,” Volpicelli said.

The doctors offer a free clinical screening to determine if a candidate can undergo treatment. The screening involves making a topographical map of the eye to look for peaks or valleys in the cornea that render the patient ineligible. A patient also must be over 18 and not pregnant to have LASIK.

Beers said he became interested in eyes during his rotation in ophthalmology during medical school at the University of California at San Francisco. He said he enjoyed working with his hands and doing the math involved. “It was the right mix for me,” he said.

His colleague, Volpicelli, said “I went into ophthalmology for a couple of reasons.” His father, who was a physician, recommended the field, and it also has an interesting blend of “medicine, infectious diseases and a chance to fix things,” Volpicelli said. There is “precision, surgery, good results and minimal pain for the patients.”

Peninsula Eye Physicians also do PRK, a procedure that removes the protective flap entirely and allows the cells to grow back in. About 5 to 10 percent of their patients choose this procedure.

For more information, call 961-2585.


May 15, 2005

Avoiding Flap Complications

Laser vision correction has come full circle from its beginnings with surface phototherapeutic keratectomy and PRK. The field advanced to lamellar refractive surgery with LASIK emerging as the dominant procedure. Today, interest in advanced surface ablation has re-emerged with LASEK and other methods.

Surface procedures offer several advantages compared with lamellar methods, particularly because the former avert rare but potentially devastating complications. Creating the permanent LASIK flap has been associated with the induction of higher-order aberrations and decreased corneal sensitivity as well as an increase in dry eye syndrome, striae, diffuse lamellar keratitis, infection, epithelial in-growth, and other intraoperative hurdles. Fortunately, the likelihood of visual loss from LASIK is very small. According to the Eye Surgery Education Council of the ASCRS Foundation, to date, less than 1% of LASIK patients have experienced serious vision-threatening problems.

LASEK, an alternative to LASIK, provides little added benefit due to the cytotoxic effects of alcohol used as a softening solution applied to the ocular surface. Alcohol causes swelling of the cornea and results in discomfort, sensitivity to light, and delayed healing. Clearly, there is a need for procedures that provide the vision correction benefits of LASEK or LASIK but that avoid complications arising from alcohol use or excessive manipulation of the corneal lamellar flap.
—Terrence P. O’Brien, MD

NORWOOD EYECARE EPIKERATOME
Mark Volpicelli, MD
An increasingly popular and rapidly growing technique in refractive surgery is Epi-LASIK. Ioannis Pallikaris, MD, PhD, of Crete, Greece, originally introduced this procedure to ophthalmologists in the US as an alternative to LASEK. The Norwood Epikeratome (Norwood Eyecare, Inc., Duluth, GA) is a fully automated, precision-engineered mechanical separator that does not use a metal blade. The device is unique in that it employs a polymethylmethacrylate plastic separator that mechanically cleaves the lamina densa epithelial basement layer from Bowman’s membrane, thus leaving a glassy smooth Bowman’s layer exposed for ablation (Figure 1). It is ergonomically designed with good “surgeon feel” with two differently sized rings to be used for variously sized eyes, similar to a true microkeratome design used for traditional LASIK.

The Epikeratome system has a well-defined geometry and is made of lightweight titanium, including a posterior applanation separator platform, which allows for reliable and predictable epithelial delamination. Because of its advanced castellation/fenestrations and differently sized rings, it achieves excellent and consistent vacuum, making the accidental loss of suction almost impossible.

EPIKERATOME CANDIDATES

Patients with flat, steep, or thin corneas, older patients whose epithelium has the potential for an “epithelial slide” with LASIK, and patients with basement membrane dystrophies are ideal candidates for Epi-LASIK with the Epikeratome. My colleagues and I are witnessing vision recovery that is faster at 1 month postoperatively compared with our PRK and traditional alcohol-treated LASEK eyes. This is probably due to the more rapid epithelial remodeling afforded by eliminating alcohol in LASEK. In addition, by providing an epithelial bandage contact lens, we can inhibit cytokine release and epithelial growth factor mediators, which may provoke epithelial haze during a more prolonged recovery process. So far, with the Epikeratome device in wavefront-customized ablations, all of our patients have returned to BSCVA by 1 month, and 74% have a UCVA of 20/20 or better at 1 month, with 84% of our patients within ±0.50D of their intended correction.

COMFORT

Of course, when compared to LASIK, Epi-LASIK is less comfortable. In our group’s experience, however, it is less painful than PRK, and it has resulted in little-to-no postoperative haze. We are currently participating in a multicenter prospective clinical trial to further elucidate and determine the optimal pre- and postoperative regimen for patients undergoing Epi-LASIK. Currently, the perfect niche for this device is in patients who might otherwise not be good candidates for LASIK due to the corneal anatomy noted earlier.

THE FUTURE OF Epi-LASIK

For Epi-LASIK to replace LASIK 100%, its slight delay in visual recovery and postoperative comfort issues would have to be resolved. Additional clinical investigations are underway to resolve this issue and to determine the best regimen of adjunctive pharmacotherapy to accelerate the recovery of these patients.

Mark Volpicelli, MD, is in private group practice in Mountain View, California. He states that he holds no financial interest in any product or company mentioned herein. Dr. Volpicelli may be reached at (650) 961-2585; volpeyes@aol.com.

EPILIFT
Terrence P. O’Brien, MD

A new technique employing a customized keratome device separates the epithelium mechanically, delaminates the corneal epithelium precisely, and exposes a smooth Bowman’s membrane layer for standard or customized laser ablation. The Epilift System (Advanced Refractive Technologies, San Clemente, CA) is a fully automated, precision-engineered mechanical tissue separator. It uses a metal blade with a specially designed geometry, including a bar applanator, to reliably achieve epithelial delamination. The Epilift console incorporates a vacuum system, software, and controls for setting tissue cleavage parameters. A dual-motorized handpiece powers the oscillation and translation of the cutting blade across the cleavage plane (Figure 2). A precisely machined separator regulates the depth of the delamination. The system offers a choice of suction rings to meet individual patients’ needs, and it is designed for use with disposable tubing sets.

HOW IT WORKS

The Epilift System was granted 510(k) status by the FDA in September 2004. It cleanly separates the epithelium between the Bowman’s layer and the basement membrane, thus leaving an intact sheet of viable tissue, which is lifted from the cornea in preparation for laser reshaping. Histopathologic studies demonstrate that the device creates a cleavage plane below lamina densa while preserving stratification of the basement membrane portion of the epithelial layer.1 Because the procedure does not involve cutting the cornea or creating a permanent flap, the epithelium can be repositioned to restore integrity to the ocular surface. As with LASEK, visual improvement is relatively rapid, yet slightly longer than with LASIK.

Preliminary experience (personal communication, Professor Chris Lohmann, MD, February 2005) suggests that the Epilift reliably and reproducibly creates epithelial flaps with good integrity and proper dimensions for customized wavefront-guided treatment. However, more research is needed.

SUMMARY

Although LASIK currently dominates and defines refractive surgery from the patient’s perspective, many individuals avoid lamellar procedures due to their small but measurable inherent risk. The Epilift offers certain advantages over PRK and LASEK, especially with respect to flap-related complications, iatrogenic ectasia, and alcohol-induced cytotoxicity. Questions remain about corneal wound healing after Epi-LASIK. Additional clinical investigations are needed to resolve this issue and to determine the best regimen of adjunctive pharmacotherapy to accelerate recovery without haze formation.

Terrence P. O’Brien, MD, is the Tom Clancy Professor of Ophthalmology and Director of Refractive Surgery at the Wilmer Eye Institute of John Hopkins University School of Medicine in Baltimore. He states that he holds no financial interest in any product or company mentioned herein.
Dr. O’Brien may be reached at via fax (410) 583-2842; tobrien@jhmi.edu.

1. Netto MV, Dupps WJ, Rayborn M, et al. Early clinical results and morphologic analysis after automated epithelial flap creation. Paper presented at: The ASCRS/ASOA Symposium on Cataract, IOL and Refractive Surgery; April 16, 2005; Washington, DC.

AMADEUS II
Eric D. Donnenfeld, MD
The Amadeus II microkeratome (Advanced Medical Optics, Inc., Santa Ana, CA) is a nondisposable microkeratome that can create conventional LASIK flaps and also perform Epi-LASIK. The addition of a PMMA Epi-LASIK blade allows this surgical transformation to occur. With the Amadeus II microkeratome, there is no need for surgeons to purchase a separate Epi-LASIK delaminator or to use a disposable microkeratome with reduced mechanical tolerances. Histopathology of the intact epithelial sheet using the Amadeus II reveals the epithelium to be viable and the separation plane to be at the level of the epithelial basement membrane with Bowman’s membrane left intact. Pathologic studies of eyes undergoing Epi-LASIK with the Amadeus II microkeratome prior to corneal transplantation reveal a smooth Bowman’s membrane with a regular cleavage plane and the absence of residual epithelium. This is an ideal surface on which to perform excimer laser wavefront photoablation.

HOW IT WORKS

The Amadeus II is made of titanium and creates a nasal-hinge flap. It has a variable hinge width, translation speed, oscillation speed, flap size, spacer, and suction (Figure 3). The hinge width can vary between 0.4 and 2.0mm. For Epi-LASIK my colleagues and I recommend a wider hinge than for conventional LASIK and have been performing Epi-LASIK with a hinge width of between 1.0 and 1.2mm depending on corneal curvature. The translation speed is decreased to 1.5mm per second and the oscillation speed is slightly increased to 11,000 oscillations per second. The microkeratome comes with four different ring sizes: 8.5, 9.0, 9.5, and 10.0mm. We have found larger ring sizes advantageous and perform most of our cases with the 9.5-mm ring. Finally, we reduce the suction level. The PMMA blade ensures a regular epithelial sheet without incursion into Bowman’s membrane.

CONCLUSION

During the last several years, there has been a significant movement to surface ablation. This trend for a variety of reasons will continue to accelerate. Amadeus II Epi-LASIK offers several advantages compared with PRK and LASEK. There is a more regular epithelial debridement and no alcohol-induced cytotoxicity with this system. Early studies show less pain and photophobia than with PRK. We look forward to further studies on haze formation and the rapidity of visual rehabilitation with Amadeus II Epi-LASIK.

Eric D. Donnenfeld, MD, is a founding partner at Ophthalmic Consultants of Long Island in New York. He is a consultant for Advanced Medical Optics, Inc. Dr. Donnenfeld may be reached at (516) 766-2519; eddoph@aol.com.

MORIA EPI-K
Barrie Soloway, MD, FACS

THE PROCEDURE

In an Epi-LASIK procedure, an epikeratome is utilized to mechanically separate the epithelial layer of the cornea from Bowman’s membrane. The epithelial flap is folded back prior to laser reshaping of the cornea and subsequently returned to its original position.
By creating a viable epithelial flap, the Moria Epi-K (Moria, Antony, France) produces better wound healing, faster visual recovery, and less haze compared with surface ablation procedures such as PRK and LASEK.

THE SYSTEM

The Epi-K System, approved by the FDA in March 2005, has a metal separator with optimal edge geometry for cleaving rather than cutting corneal tissue. Separation occurs along the natural cleavage plane between the basement membrane and Bowman’s layer. To minimize the risk of inadvertently cutting stroma, the separator is encased in a disposable plastic head that contains an applanation plate (Figure 4).

The Epi-K handpiece is specifically calibrated to advance at an appropriate speed for epithelial separation. Two independent motors in the handpiece drive the separator oscillation and advancement of the head.

The Epi-K is driven by the Evolution control unit, which also operates all Moria’s automated (LASIK) microkeratomes. The system includes a low-vacuum option on the reverse pass to minimize overall suction time and maximize patients’ comfort.

CLINICAL STUDIES

The safety and efficacy of Epi-LASIK with the Epi-K have been demonstrated in clinical trials of 530 eyes in 14 centers in nine countries.1 The investigators reported that the device produced excellent epithelial flaps. Visual outcomes were similar to those of other laser vision correction procedures, and there was no significant incidence of haze. Postoperative pain was less and visual recovery faster than that typically associated with PRK or LASEK. Eighty-eight percent of patients at the New York Eye and Ear Infirmary were able to return to work within 3 days of surgery.

SUMMARY

In recent years, refractive surgery has experienced a growing trend toward surface ablation, due to its inherent safety, as well as the prospect of better visual outcomes. This movement has been tempered by the disadvantages of the current surface ablation procedures, PRK and LASEK. Epi-LASIK produces significantly better results than those procedures with regard to wound healing, visual recovery, and haze. Clearly, Epi-LASIK will become the procedure of choice for surface ablation, and most refractive surgeons will want to offer their patients both LASIK and Epi-LASIK.

LASIK is a mature technology with little room for further advancement. Thus, the flap effects inherent in the procedure may not be amenable to significant improvement. Now that we have an effective epikeratome, and as we continue to improve the procedure, it is conceivable that Epi-LASIK may one day become the corneal refractive procedure of choice.

Barrie Soloway, MD, FACS, is Director of Vision Correction at the New York Eye and Ear Infirmary, and Assistant Professor of Ophthalmology at the New York Medical College. He states that he holds no financial interest in any product or company mentioned herein. Dr. Soloway may be reached at (212) 758-3838; bsolowaymd@pol.net.

1. Soloway B, Starr C, Jardim D. Epi-LASIK with the Moria Epi-K worldwide clinical trial results. Paper presented at: The PAACO 2005; April 2005; Dubai, United Arab Emirates.


August 22, 2001

New techniques for cataract surgery

Category: Cataracts

Just 50 years ago, having cataract surgery meant general anesthesia, a five-day stay in the hospital, a high risk of infection and wearing thick corrective glasses for the rest of your life. That’s not the case today.

Cataract surgery has undergone revolutionary changes since then, especially in the past decade. It’s now an outpatient procedure, taking just 20 minutes, done without stitches, usually with just a topical anesthetic.

Doctors implant the corrective lens within the eye. The modern lens implant actually can improve vision by correcting a patient’s nearsightedness, farsightedness and even astigmatism – blurry vision resulting from an irregularly shaped cornea.

“In the 1990s, there’s been a paradigm shift in cataract surgery,” said Mark Volpicelli, a Mountain View ophthalmologist. “Not only can we get rid of the opacity in the eye, we can get rid of the refractive (visual acuity) problem.” Volpicelli said he usually performs about six cataract procedures each Tuesday morning at the El Camino Surgery Center in Mountain View.

Cataracts are the leading cause of vision loss in adults 55 and older. Usually a result of aging, a cataract is a clouding of the eye’s natural lens, the part of the eye responsible for focusing light and producing clear, sharp images. Old cells in the lens die and are replaced with new ones, but over time, the old cells begin to block and diffuse light as it passes through the lens.

Cataracts more typically appear in older adults, mostly those over 65. However, they can also occur as a congenital condition in children, or in younger adults due to diabetes, autoimmune conditions or the use of steroids, Volpicelli said.

Cataracts usually come on slowly, they may not occur in both eyes at once, and the symptoms may be vague. A patient may notice they are having trouble reading or driving at night, or they might be bothered by glare from bright lights. Frequently, someone might not be aware of a vision problem until failing the vision test for a driver’s license renewal. The point at which most ophthalmologists usually recommend surgery – and Medicare or other health insurance is willing to pay – is when a patient’s vision reaches 20/50.

The surgical procedure for cataract removal and lens implantation is painless and quickly completed – about 20 minutes. The patient arrives at the surgery center about an hour prior to the procedure. Topical anesthetic is applied to the affected eye. Looking through a magnifying device, the physician uses a small diamond blade to make an incision just one-eighth of an inch long. In a process called phacoemulsification, an ultrasonic instrument uses sound waves to break the cataract into tiny pieces, which are suctioned out, leaving behind the intact portion of the lens capsule. A soft, foldable lens is then inserted through the incision. Once inside, the lens is unfolded and set into place.

The newest type of lens implant used for vision correction after cataract surgery is called the multifocal lens.

“With the multifocal lens, 40 percent of my patients no longer need glasses,” he said. The multifocal lens can also be implanted in patients in their 40s or 50s, who don’t have cataracts, but are seeking an alternative to glasses or laser vision correction. The multifocal lens implant is designed with concentric rings that allow the patient to see near, far and in between, much like variable lens glasses, but without the distortions. “It’s not a perfect scenario for replacing youth, but (it’s) pretty good.”

After cataract surgery, the patient remains for a short period of observation and then can go home to resume normal activities, such as reading, driving and light work, within a day after the procedure. The majority of patients will experience improvement in their vision the day following surgery.

With faster, less invasive, more sophisticated techniques, cataract surgery has become safer and more effective. “I did surgery on an 80-year-old last year, and on a 101-year-old,” Volpicelli said. “They both did very well.”


October 18, 2000

Getting the Full Picture About Lasik Eye Surgery

Category: LASIK

If your eyes are the windows to the soul, then Lasik eye surgery is becoming an ever-popular way of making the view less blurry.

According to the Federal Trade Commission, since Lasik eye surgery was approved in 1995, laser eye centers have mushroomed from 300 in 1996 to more than 900 centers today. Five years from now, the FTC said, surgeons are expected to perform laser eye surgery on more than 3 million pairs of eyes.

Dr. Dan Beers, who performs Lasik vision correction with the Peninsula Laser Vision Medical Group, located in Mountain View, said, “The key is for potential patients to talk with their doctors about (the doctor’s) level of experience and to speak with a former patient of the doctor they are considering.”

Laser eye surgery is a delicate procedure, Beers said, involving the cornea, “which is responsible for bending light that enters the eye and focusing it on the retina.” In people whose cornea is too steep or too flat, the image becomes blurry, Beers said.

“Laser eye surgery reshapes the cornea,” Beers said, “by using a Microkeratome, or a blade device, to remove a flap from the top of the cornea.” Then, a laser is used to reshape the cornea and the flap is repositioned in place. “This method allows the top layer of cells in the cornea to remain intact, and speeds recovery,” Beers said.

The surgery is out-patient, Beers said, and the patient is asked to rest on the first night, using antibiotic and anti-inflammatory drops every two hours. Beers said that “within 12 hours, the vision should be clear.”

Although Beers said the risks are few, patients should be knowledgeable as to what to expect. For instance, Lasik eye surgery doesn’t always result in 20/20 vision. “Though it is unusual,” Beers said, “the surgery may not provide all patients with as good a vision as they had with glasses or contacts.”

Also, if the patient has large pupils, which dilate excessively late at night, then the patient might “see glares or halos at night, after the surgery,” Beers said. In addition, “in one out of every 1,000 or 2,000 patients, the flap of the cornea is not perfectly cut, and is irregular, at which point (the surgery) cannot proceed,” Beers said.

Of course, as with any surgery, there is a risk of infection, but Beers said that to mitigate this problem, “antibiotic drops are used before, during and after the procedure.”

Ultimately, Beers said, there is a 95 percent success rate for attaining 20/20 vision, which is even higher with a procedure called “enhancement.” The enhancement is used to fine-tune the patient’s vision and involves lifting the flap again six weeks after the original procedure.

Beers said that careful and precise measurements can lower the need for enhancement. Before the surgery, Beers said, “patients should make certain that the doctor is taking the measurements and not a technician.”

Even with all these possible risks and side effects, Beers said, “in the more than 2,000 patients that I have treated, no one has regretted having the procedure done.”

For more information on Lasik eye surgery, call (877) FTC-HELP or visit www.ftc.gov.