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Clinical Update Clinical Update Femtosecond Laser Brings New Level of Precision to Cataract Procedures The femtosecond laser has increased the the time the eye is open and eases stress on accuracy of the most common surgical the eye’s internal structures. And with such procedure in the United States, according to accuracy at our disposal, we anticipate the laser the surgeon who was instrumental in bringing will open new avenues of treatment that have the advanced tool to the UCLA Stein Eye never been possible before.” Institute last year. Surgeons at Stein Eye have been using the The Alcon LenSx, now used for precision cataract femtosecond laser to assist with several procedures at the Institute’s outpatient surgical steps of cataract surgery, including corneal center, emits optical pulses at the unimaginably incisions to remove the cataract and manage short duration of a femtosecond––one-millionth astigmatism, lens softening, and making an of one-billionth of a second. opening in the capsular bag. “A femtosecond laser can be thought of as For cataract procedures, the femtosecond laser a microscalpel, incising the cornea and lens system is gently docked to the patient’s eye capsule and breaking up the cataract on a and optical coherence tomography imaging Dr. Kevin Miller uses the Alcon LenSx femtosecond laser microscopic scale with an incredible level is used to map the eye’s internal structures. to assist with several steps of cataract surgery, under of precision,” says Kevin M. Miller, MD, Before the operation, the surgeon programs imaging guidance. The femtosecond laser enables Kolokotrones Chair in Ophthalmology. “With the location and size of the incisions as well physicians in the UCLA Stein Eye Institute’s new outpatient surgical center to operate more efficiently a femtosecond laser, I can operate more as the region of the lens to be softened. After and with increased precision. efficiently and more precisely. The laser reduces continued on page 2 Macular Imaging with Spectral Domain OCT Proving June 2016 JUNE 2016 Vol.25 | No.2 VOL. 25 | NO.2 Beneficial for Glaucoma Patients In This Issue A growing body of evidence points to the The advances over the last decade in SD- benefits of macular imaging with spectral OCTs, which facilitate an assessment of the Femtosecond Laser Brings domain optical coherence tomography layers of the macula through structural and New Level of Precision to (SD-OCT) in glaucoma patients––both for imaging measures, have led to a shift in the Cataract Procedures early detection and for monitoring disease thinking about glaucoma progression. “For progression, according to Kouros Nouri- a long time we believed that the central part Macular Imaging with Spectral Mahdavi, MD, MSc, associate professor of the retina, where the macula is located, Domain OCT Proving Beneficial for of ophthalmology and director of the sustains damage very late in glaucoma. But Glaucoma Patients Glaucoma Imaging Research Laboratory at new evidence has shown that the damage to the UCLA Stein Eye Institute. the retinal ganglion cells in the central part of the retina actually occurs early in the continued on page 2 Femtosecond Laser Brings New Level of Precision to Cataract Procedures continued from cover Macular Imaging with Spectral Domain OCT Proving Beneficial for Glaucoma Patients imaging, the surgeon can make adjustments “The outpatient surgical center’s facilities continued from cover to the location and size of the incisions and are excellent and complement the talents of the region of lens softening. A foot pedal our medical team,” says Bartly J. Mondino, disease,” says Dr. Nouri-Mahdavi. “By using is then depressed, which fires the laser to MD, chairman of the UCLA Department of SD-OCT to measure the mass of ganglion cells create the incisions and lens fragmentation Ophthalmology and director of the Stein Eye in the macula, we can gauge the damage to these pattern. The eye is undocked from the laser, Institute. “Everything about the center was cells at various stages of the disease, making it and the patient is moved under the operating planned with enlightened ideas about patient useful both potentially for detection of early microscope. The surgeon proceeds to remove well-being and medical efficiency.” glaucoma and for identifying deterioration of the cataract and implant the intraocular lens the disease in later stages.” While early detection to complete the surgery. While focusing on patient comfort and the is important for treating and preventing visual most up-to-date surgical equipment, the loss from glaucoma, he notes, the ability to Cataract procedures are already highly successful, center also serves as an incubator for future detect worsening of the disease is critical for Dr. Miller notes, but the femtosecond laser offers advanced applications. To promote teaching monitoring the impact of treatment. an incremental improvement in the precision and training, an adjacent seating gallery allows and reproducibility of the incisions for modifying visiting doctors to observe surgical procedures Dr. Nouri-Mahdavi notes that approximately the patient’s astigmatism and for removing the without scrubbing, while monitors display half of the retinal ganglion cells (RGCs)––the cataract. “It can make a 90-degree turn inside the the same view of the eye the surgeon is seeing cells damaged in glaucoma––are located in the cornea, which we can’t possibly do with a metal through the microscope. A video system macula within 4–5 millimeters of the foveal blade or diamond knife,” Dr. Miller says. “And it captures surgical procedures, which can be center, and these tend to be the last ganglion eliminates surgeon variability by stamping out a distributed as educational tools, reviewed by cells to die. That means that in advanced disease, perfect incision every time.” colleagues at other institutions, and used for when other structural parameters such as those live streaming at conferences. involving the optic nerve head and retinal But the femtosecond laser does more than nerve fiber layer (RNFL) are no longer useful, produce precise repeatable incisions in cataract The facility features the Intraoperative measurements of the macula can still be used to procedures. It also makes a perfectly round Refractive Guidance Systems, including the detect deterioration, he says. and centered opening in the anterior lens Zeiss Callisto Markerless System, the Alcon capsule––the capsulorrhexis. This has benefits Verion Image Guided System, and the Alcon Another important reason to image the macular that go beyond the cosmetic and into the realm Optiwave Refractive Analysis System, all region in glaucoma is that the macula is the only of improving safety, Dr. Miller notes. of which increase the level of precision in part of the retina where the RGCs are present procedures. The Zeiss and Alcon Verion systems in up to 6 to 7 layers, with 30 to 35 percent of In addition, by pre-softening the cataract, track the position and orientation of the eye retinal thickness. “It is much easier to measure the femtosecond laser reduces the amount of during surgery, creating a digital overlay that is where these cells are piled up,” says Dr. Nouri- cumulative dissipated energy needed––thereby linked directly to surgical tools in the operating Mahdavi. “Moreover, there is likely to be low reducing the time spent emulsifying the room. The Alcon Optiwave measures the eye’s measurement variability in the central macula, cataract with ultrasound. This is particularly power, which assists the surgeon in choosing the which is populated by only smaller blood vessels. important for dense-cataract patients, most accurate lens implant. From a technical point of view, the macula is a improving safety by limiting exposure as well fairly flat area, so performing segmentation–– as leading to faster recovery. Looking forward, Dr. Miller believes new lens measuring layers separately––is a reasonably designs will take advantage of the technology’s simple task.” The femtosecond laser is one of many capabilities, including the precisely sized and new tools being used at the Institute’s positioned capsulorrhexis. “Multifocal lenses The OCT technology is such that machines can outpatient surgical center, which opened in have to be perfectly centered on the pupil to now measure individual layers of the macula, February 2015. Located in the Edie & Lew function at their optimum,” he says. “Locking one by one. Dr. Nouri-Mahdavi and colleagues Wasserman Building, the facility includes the lens implant in would ensure quality are investigating whether measuring the six operating rooms, examination areas, and each time. That is just one example of what I ganglion cell layer by itself provides information support facilities devoted to the full range of anticipate will be many new compelling reasons that is more useful than what could be gathered ophthalmic treatment. to use the femtosecond laser in the future.” by using the combined inner layers of the continued on page 3 WWW.JSEI.ORG DIRECT REFERRAL LINE (310) 794-9770 page 2 An example of follow-up macular images on an SD-OCT device. (Left) The macular image showing macular full thickness measurements in an 8 x 8 array centered on the fovea, the macular center. (Center) The baseline and follow-up images are accurately superimposed. (Right) The difference in thickness between the baseline and follow-up image is represented. The red arcuate area demonstrates a localized region where the entire thickness of the macula has thinned out, suggesting progression of glaucoma damage. macula. In addition, many devices now come macular damage is most likely to occur early to be found. A second category of patients for with software that is customized for glaucoma in glaucoma. The axons going to that area tend whom SD-OCT is useful consists of those with analysis, Dr. Nouri-Mahdavi notes. to be those from the inferior macular region, retinal ganglion cell loss in the central region, making this region a prime area of interest for such as highly myopic patients or those with Dr.
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