Why Toric IOL Marking Methods Still Matter?
by Liz Hillman, Editorial Co-Director
Manual, digital, or a combination of both—toric IOL alignment methods continue to be an important topic.
“Ten years ago, there were predictions that manual marking would disappear, but it’s still widely used,” said Soroosh Behshad, MD, MPH, who uses both manual and digital marking with his toric cases.
The continued relevance of both methods, Dr. Behshad said, stems from the fact that each has distinct advantages and limitations.
Dr. Behshad said he marks the meridians preoperatively using a corneal marker that hooks into his cell phone, then uses the toriCAM app by Graham Barrett, MD, to aid in aligning his marks. In the OR, he has access to a Callisto (Zeiss), which he uses to confirm he is aligning toric IOLs correctly. He noted that having both options enhances his confidence in achieving proper alignment.
Among the key benefits of manual marking, Dr. Behshad said, are its low cost, simplicity, and efficiency. To ensure accuracy with manual marking, Dr. Behshad said he talks his patients through what he’s doing every step of the way because they’re sitting up and haven’t had anesthesia yet. In addition, as a cornea specialist, he said regardless of if you mark manually, digitally, or use both for toric alignment, success in the postoperative period begins with careful preoperative preparation. He said to look at the ocular surface, manage dry eye, pterygium, anterior basement membrane syndrome, and other pathologies that would affect your preop calculations.
Dr. Osher, like Dr. Behshad, uses a “belt and suspenders” approach, as he put it. Dr. Osher said astigmatic correction at the time of cataract surgery dates to the early 1980s when he introduced astigmatic keratotomy combined with phacoemulsification for the reduction of pre-existing astigmatism. This technique, he said, was more art than science. With the invention of the toric IOL in the 1990s by Kimiya Shimizu, MD, astigmatic correction became a science.
Over time, Dr. Osher created a technique called iris fingerprinting to accurately perform manual marking for toric alignment.1 Iris landmarks, unlike blood vessels, don’t change from the preop dilated exam to what surgeons see in surgery. Dr. Osher said he uses a Haag-Streit camera to take a picture of the patient’s iris, and with that photograph, he draws a horizontal line at 0 and 180, followed by the inferior 90-degree mark. “These give me three reliable landmarks to guide me during surgery,” he said. “I hang those photographs on the microscope and keep them beside me throughout the case.”
In surgery, Dr. Osher would make very small, almost imperceptible dots on the conjunctiva with a cautery pen called ThermaDot.
“Once I place my ThermaDot, I know I can align that lens precisely,” In addition to alignment with the manual marks, Dr. Osher uses a circular dial called the Osher-Mendez marker, confirming his correct ThermoDot placement.“I then activate the Callisto system, and 99% of the time, the target meridian matches perfectly,” he said.
Dr. Osher acknowledged peer-reviewed studies that have concluded the results with manual vs. digital markers are similar. However, he noted that even a few degrees off on alignment can affect outcomes. He emphasized that taking a dual approach with precise manual marking confirmed intraoperatively with a digital system requires more time and financial investment—but the result justifies the effort. Dr. Osher said that if the patient is paying out of pocket for a toric lens and with one shot to get placement right in the OR, it’s worth it.
“I’m willing to spend extra time and effort because it satisfies my OCD and supports my belief that we have one chance to give the patient the best vision of their life,” he said.
Having the manual markings, Dr. Osher added, is also a safety net should the digital marking system fail when needed for whatever reason.
“There’s a beauty in this dual approach—a safety net because you never know what might go wrong,” Dr. Osher said, noting that images might not make it into the medical record, digital systems can freeze, and thumb drives can be lost. “I carry every iris fingerprinting image with me in my briefcase every day.”
Both Bryan Lee, MD, JD, and Mitchell Weikert, MD, said they prefer digital marking for their toric IOL cases.
“Digital marking has demonstrated superior accuracy compared to manual marking, and it also streamlines workflow in both the preop area and operating room,”Dr. Lee said. “If you adjust the axis using intraoperative aberrometry, digital markers can easily be repositioned for a final alignment check at the end of surgery.”
The pro of manual marking, Dr. Lee said, is that it is a fallback option if digital images cannot be used, and digital marking is not available 100% of the time. “But whenever it is available, I always use it,” he said.
“There’s a beauty to having this dual approach, a safe approach, because you never know.”
Robert Osher, MDDr. Weikert relies primarily on digital marking and for those where the cost of such a system isn’t an issue, he would say
“digital marking all the way.”“If you’re investing in this technology, make sure it’s economically viable based on how you implement it,” he said.
Dr. Weikert mentioned the creation of laser capsulotomy marks via the femtosecond laser. This capability, available on the LENSAR Laser System (LENSAR), eliminates parallax errors associated with some other digital markers.
But just because you have a digital marking system does not mean you’re out of the woods from using manual marking, Dr. Weikert said. “Last week, I had a couple of patients where we couldn’t capture a usable image,” he said. “This could be due to ptosis or alignment challenges that prevent obtaining a complete image for digital use.”
Dr. Weikert also said that with digital markers, you need to make sure you can reconcile what you’re seeing under the
scope with what’s up on the monitor. “Sometimes there’s a slight delay with digital systems,” he said. “I usually mark the eye at the start of surgery when I first get my reference, then I compare that to the monitor image, which tends to be more static and stable than what’s visible through the microscope.”
The discussion of manual and digital marking is still an important one, Dr. Weikert said, especially when you think about it in the context of toric IOL market penetration, which he said is “shockingly low.”
“Toric lens penetration was 8.4%,” Dr. Weikert said, citing 2023 data. That means more than 80% of cataract procedures use non-toric, monofocal IOLs. Why? Some of it is cost and the burden of patient expectations, but part of it may be concern about accurate results. Are [surgeons] worried about aligning the lens? If comfort with alignment is part of the hesitation, improving that comfort may increase adoption.”
ASIA-PACIFIC PERSPECTIVES
Samaresh SRIVASTAVA, MD
Consultant, Raghudeep Eye Hospital
A-16 Shanti Path, Tilak Nagar, Kaipur
samaresh@raghudeepeyeclinic.com
The authors have presented a compelling discussion on the ongoing relevance of toric IOL marking methodology, highlighting an important truth that resonates throughout ophthalmology: the value of manual techniques despite the emergence of automation in every aspect of our ophthalmic practice.
I believe that markerless intraoperative alignment systems are undoubtedly a step forward in improving ease and precision with toric IOLs. Using an automated capture in the preoperative evaluation, followed by seamless transfer of data into the operating room and display on the surgeon’s screen can significantly ease the learning curve for surgeons transitioning to toric IOL implantation. Further, since most of these systems also compensate for cyclotorsion of the eye, a more accurate axis placement may be expected. This technology will also help address Dr. Weikert’s observation about the surprisingly low toric
IOL penetration rate of 8.4%. The reluctance to adopt toric IOLs may in part stem from surgeon uncertainty about accurate alignment.
Dr. Osher’s “belt-and-suspenders” philosophy, which combines the use of preoperative digital photography with intraoperative alignment systems, would indeed enhance precision. However, whether it will be practically feasible, particularly in high volume practices to rely on both methods may be a question.
On the other hand, a large part of the world continues to rely on manual axis marking, both pre- and intraoperatively. I still strongly feel that manual marking, whether free hand, using pendular markers or on the slit lamp, still has a definite role to play even today. Technology comes at a heavy price, and there may be errors or malfunction even with the best technology. However, when viewed through the lens of improved surgeon comfort and potentially increased toric IOL adoption rates, this investment may yield substantial returns both in patient satisfaction and practice growth. Yet, I feel that every surgeon must be conversant with at least one method of manual axis marking.
The discussion illuminates a broader principle in surgical practice: the most robust outcomes often emerge from
layered safety systems rather than reliance on any single technology. As we continue to refine toric IOL implantation
techniques, maintaining this philosophical approach of combining proven manual methods with advancing digital
technologies will likely yield the highest precision and surgeon confidence, ultimately benefiting our patients’
visual outcomes.
Editors’ note: Dr Samaresh Srivastava disclosed no relevant financial interests.
About The Physicians
Soroosh Behshad, MD, MPH | Associate Professor of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, California | sbehshad@hs.uci.edu
Bryan Lee, MD, JD | Altos Eye Physicians, Los Altos, California | bryan@bryanlee.pro
Robert Osher, MD | Professor of Ophthalmology, University of Cincinnati, College of Medicine, Medical Director Emeritus, Cincinnati Eye Institute, Cincinnati, Ohio |
rhosher@cvphealth.com
Mitchell Weikert, MD | Professor, Cullen Eye Institute, Baylor College of Medicine, Houston, Texas | mweikert@bcm.edu
Relevant Disclosures
Behshad: None
Lee: Zeiss
Osher: None
Weikert: Heidelberg, Zeiss
Reference
1. Osher RH. Iris fingerprinting: new method for improving accuracy in toric lens orientation. J Cataract Refract Surg. 2010;36:351–352.
This article originally appeared in the June 2025 issue of EyeWorld. It has been slightly modified and appears here with permission from the ASCRS Ophthalmic Services Corp.
Source: EyeWorld Asia-Pacific | September 2025
