We have been lucky enough to be one of the first sites to perform refractive laser-assisted cataract surgery (ReLACS) with the LenSx laser at Vance Thompson Vision in Sioux Falls, S.D., where I practice. Straight out of the box, I found this to be an impressive technology that was an improvement over standard cataract surgery, particularly the ability to perform astigmatic keratotomies and beautiful, perfectly-centered and round capsulorhexes. As I stepped on the pedal to begin my first ReLACS procedure, I felt like I was operating sometime in the future; the quality of the imagery and the precision of the laser was incredible. Based upon my initial experience with ReLACS, which I describe in this article, I can say confidently that the hype surrounding ReLACS is justified and the technology is an improvement over manual cataract extraction. Dr. Berdahl also videotaped one of his first ReLACS cases.
First four cases
My first ReLACS patient was a family friend in her 70s with 2.5 D of astigmatism who was hoping to decrease her need for glasses, wanted a monofocal lens and was interested in having laser-assisted surgery.
As we started the procedure, she lay underneath the laser, looking at the fixation light. The docking system was applied effortlessly. The parameters were adjusted on the laser to position the astigmatic keratectomy (AK) in the main corneal wound so that the laser was more than 1 mm away. The AK was calculated for a 9-mm optical zone. After using the real-time OCT image to determine the proper plane of the capsulorhexis, in addition to the sectioning of the lens, the treatment was confirmed and finalized. Approximately one minute later, the treatment was complete.
The patient was then brought to the operating room and the paracentesis was opened. Intracameral lidocaine and viscoelastic were instilled. The main wound was opened, and the capsulotomy was removed. The lens divided easily and was removed. The remainder of the cataract surgery was typical. Afterward, I opened up the AK and was impressed to see, using the ORange intraoperative aberometer (WaveTec Vision, Aliso Viejo, Calif.), how the astigmatism had decreased to about 0.3 D. Prior to opening the AK, I had measured the astigmatism at about 2.25 D.
On postoperative day one, the patient had 20/30 UCVA, with very little corneal edema. At postoperative week one, she was seeing 20/25 uncorrected with 0.5D of astigmatism. Her refraction was the same at three weeks.
We placed the ReSTOR 3.0 multifocal lens in the second patient, a 62 year old with 1.5 D of astigmatism. This case proceeded just like the first, since the laser took the most critical steps of surgery out of my hands and completed them with impressive precision. The surgery went beautifully. Vision on postoperative day one was 20/25 uncorrected, with J2 near vision and minimal astigmatism. The patient was 20/20 J2 at three weeks.
I did not perform the lens sectioning for the third case, a 47 year old with a posterior polar cataract, because I was worried that if the patient had a posterior capsule congenital defect, any pressure induced by bubbles in the lens could cause a premature blowout of the posterior capsule. I just used the laser to create the wounds in a capsulorhexis. The patient did not have a significant astigmatism that required correction. The laser again performed beautifully at correcting the capsulorhexis and the clear cornea wounds. Fortunately, the posterior cataract was not completely fused with the capsule. After the lens was removed, I was able to rub the posterior plaque off of the capsule, and the Tecnis multifocal lens was placed in the capsular bag. I was impressed with how well-centered the lens was, with the ideal ½-millimeter overlap around the optic.
The fourth case, which I had expected to be the most challenging so far, was a 14-year-old patient with a traumatic cataract. He had been hit in the eye with a pellet from a soft air gun two years earlier. He did not have any phacodonesis preoperatively but had developed a 2+ posterior subcapsular cataract. Because his other eye was emmetropic and pediatric capsules are challenging to deal with, I felt that he could benefit from a laser-created capsulotomy. I was worried about whether the suction from the laser would be too difficult for him and if he would be able to hold still through the procedure. Much to my relief, he did well and felt that the pressure induced by the laser was minimal. In this case, I performed only the capsulotomy, which was created perfectly, because the patient had very little astigmatism and I wanted to limit the amount of time he was underneath the laser.
When I brought him into the operating room, it appeared initially that the capsulotomy might be decentered. But upon further inspection, I found that it was perfectly centered on the visual axis and that the patient had an asymmetrically dilated pupil, which gave the impression of a decentered capsulotomy. The capsulotomy was removed easily within the eye, and very little phacoemulsification energy was used to remove the lens. The Tecnis multifocal lens was centered nicely in the eye.
On postoperative day one, the patient was 20/30 J1. At one week, he was 20/20 -1 with J1 vision and had noticed a dramatic improvement in the quality of his vision. At three weeks, he was 20/20 J1.
Promise of greater precision
The LenSx laser performed well despite the challenging nature of these initial cases. I was happy with the minimal amount of residual astigmatism that the patients had on postoperative day one and how quiet their eyes were. The patients were pleased with their vision, and the incisions were completely sealed on the first day.
As I discuss ReLACS with patients, they intuitively seem to grasp the concept of having the laser carry out the most critical portions of cataract surgery, which were previously performed manually. They understand that creating a 5 ½-mm perfectly round capsulorhexis by hand isn't 100 percent reproducible even in the most experienced hands. We have been very careful not to overpromise the capabilities of the laser, yet patients naturally seem to feel that this would be the best procedure for their eyes.
It is clear to me that laser cataract surgery will bring an unprecedented level of precision to one of the most common surgeries performed in the United States. As patients are increasingly demanding greater spectacle independence and specific refractive outcomes, I believe that ReLACS will become an indispensable part of the cataract surgeon's armamentarium.
I am not sure how this technology could evolve to a higher level, but I am confident that it will. I am particularly excited about the melding of refractive and cataract surgery and how multiple technologies, such as the ORange intraoperative aberrometer, ReLACS and improved IOLs, will come together to improve the refractive outcomes of our patients.
Dr. Berdahl has no financial interests related to this topic.