As femtosecond laser use increases for different indications, the need for precision in all aspects of surgery will also grow.
New testing and diagnostic devices have the potential to improve outcomes, especially in implantation of premium IOLs with the advent of femtosecond laser-assisted cataract surgery, according to a surgeon.
Surgeons will likely become more comfortable offering surgical treatment modalities such as toric and multifocal IOLs and performing some astigmatic incisions intraoperatively, H. Burkhard Dick, MD, OSN Europe Edition Associate Editor, said.
“Currently we have new, interesting devices. For example, the SMI Surgery Guidance technology and the keratoscope from Mastel,” Dr. Dick said. “We have new devices that definitely allow you to at least have the potential to improve outcomes. The partial coherence interferometry for IOL power determination — Zeiss IOLMaster, Haag-Streit Lenstar — in Germany is a general tool. I would say that everybody uses it.”
The Pentacam HR Scheimpflug camera (Oculus) or a similar topography device is crucial for premium IOL implantation, he added.
H. Burkhard Dick
“I think these are the minor steps to further improvement and greater acceptance of premium IOLs,” Dr. Dick said. The topic is especially important now with recent innovations in femtosecond cataract surgery, including the ability for greater precision in terms of depth, architecture, angulation, length and placement of the incision. The intrastromal cut also reduces risk of surface issues such as infections and foreign body sensation.
“This is one of the top stories currently because people are very interested in this topic. They see the need to offer [technology] that everyone is willing to approve and, especially in Germany, you can now offer this and you are paid for premium IOLs, so that means that we’ll definitely improve the interest,” Dr. Dick said.
Greater acceptance of premium IOLs will also enable surgeons to gain experience with the implants and improve outcomes.
“More and more surgeons will feel comfortable if they improve their surgical outcomes, and with the use of the new modalities, this will definitely further enhance the outcome,” Dr. Dick said.
Toric IOL alignment
New devices for toric IOL alignment offer a good example of technological improvements in diagnostics and testing. The SMI Surgery Pilot seems promising in this field, Dr. Dick said. The tool provides a real-time registration and tracking overlay intraoperatively via the microscope and eliminates the need for manual marking, according to the company’s website.
Intraoperative use of a self-illuminated intraoperative LED ring keratoscope (Illuminating Surgical Keratoscope, Mastel Precision) with fixation light to align a multifocal toric IOL to the target axis and line of sight.
Image: Dick HB
Dr. Dick has performed more than 400 implantations using the device.
The device can integrate topographic information as well as measured data into the surgical guidance tool as high-definition photographs showing vessels and pigment, including the line of sight. With this tool, the paracentesis, main incision and target capsulotomy size as well as the true corneal steepest meridian can be projected on a high-resolution image that is similar to a biomorphometric photograph.
“Interestingly, there is a camera integrated in the light path of the operating microscope, so the picture of the eye is captured continuously by the surgical guidance tool and it is tracking the eye, irrespective of if the eye is moving because of the topical anesthesia or if you zoom in or out — it’s tracked immediately. This includes the capsulotomy, which is then displayed into the light path so the surgeon can see it and perform the capsulorrhexis accordingly,” he said.
The device also displays the target axis.
“The interesting thing also for me … was that even if you apply a peribulbar or retrobulbar anesthesia and have a distinct conjunctival bleeding, it still tracks. That means we don’t need to have a marker. It just displays what we want, where you have to place the incision,” Dr. Dick said.
The device increases safety by ensuring that the correct eye is operated. It is also easy to use and should be a helpful tool in the surgeon’s armamentarium, he said.
Another example of the new technology is the illuminated keratoscope (Mastel Precision), an affordable device using LED lights that is placed underneath the microscope and aids in centration of toric and multifocal IOLs.
“In the middle there is a blinking light, and under topical anesthesia the patient is asked to look at the blinking light, and by the reflex on the cornea you see directly where the line of sight placement is on the cornea,” Dr. Dick said. “I had cases where I thought the multifocal lens was placed perfectly centered. As a matter of fact, when I looked where the patient was looking, I saw the patient was looking at the paracentral ring, and with a little movement to the center, it was perfectly centered.”
The reflection of the LED lights on the back side of the IOL guides placement by showing the implant’s relation to the toric mark when the IOL is placed in the correct position.
“For me, it’s the cheapest way to, without any need of marks, help aligning the IOL at the corresponding axis,” Dr. Dick said. “It’s very valuable.”
While the current offerings are promising, the various diagnostic and testing technologies could benefit from being merged into a single system, Dr. Dick said. The devices make a significant impact in their separate tasks but together could offer greater synergy. When the surgeon requires data that span several devices, sterility and other issues can pose problems.
“I think for the future, it will be an important task for the companies to first provide the surgeon [more integrated] information, because I’m convinced that by using these devices and these helpful means we will further improve surgery,” Dr. Dick said.
By enabling improvement in surgical outcomes, the new devices may increase the potential of premium IOL surgery.
“If you offer premium IOLs, the patient expects super outcomes, and the results are already good. But if you compare it to LASIK or other procedures in terms of predictability and refractive outcome, there’s still the need to improve because we are not as good as we would like to be, and I think these [devices] will definitely help,” Dr. Dick said. – by Erin L. Boyle
For more information:
- H. Burkhard Dick, MD, can be reached at Center for Vision Science, Ruhr University Eye Hospital, In der Schornau 23 – 25, DE-44892 Bochum, Germany; +49-234-2993101; fax: +49-234-2993109; email: email@example.com.
- Disclosure: Dr. Dick is a consultant for OptiMedica.