Cataract surgeons delved into the various intraocular lens (IOL) options and surgical approaches that do not require capsular support on the second day of the recently held ESCRS Winter Meeting 2022. The session was co-chaired by Prof. Jorge Alio and Prof. David Spalton who announced that he was retiring as session chairperson after over 30 years of serving as such at ESCRS meetings.
The ideal place for an IOL is typically within the capsular bag. But this is not always possible due to lack of capsular support caused by trauma, genetic causes and complicated ocular surgery, among others. This necessitates alternative surgical approaches such as IOL placement in the anterior chamber, scleral fixation and iris fixation.
Anterior Chamber Angle Supported IOLs
According to Dr. Richard Packard from the United Kingdom, anterior chamber (AC) IOL implantation is a simple procedure when there is not adequate capsular support. The Kelman Multiflex design, which dates from 1980, is the standard shape for all ACIOLs now.
He shared insight from a 2016 study that showed that when faced with inadequate capsule support, 58.6% of surgeons would place a primary ACIOL, 29.3% would place a primary scleral-fixated posterior chamber (PC) IOL, and 5.3% would leave the patient aphakic for secondary scleral-fixated PCIOL placement.
“Given that ACIOL use seems popular with 50% of surgeons when there is an inadequate capsule, we need to have devices to measure the white-to-while incision size; an understanding of correct lens sizing (white-to-white plus 1 mm); an adequate IOL bank of three sizes for each IOL power; awareness of the need to recalculate for the correct A constant; miochol to constrict the pupil; sheets lens glide to assist implantation; and cohesive viscoelastic. A vitrector is required to do anterior vitrectomy as needed and make an iridectomy, and triamcinolone is required to expose vitreous as part of the AC cleanup,” he said.
“Although in the past ACIOLs had poor results, the current design has stood the test of time. Results compare favorably with scleral fixation of PCIOLs. In a compromised eye, the implantation technique is straightforward and quick, thus not prolonging an already longer procedure,” he noted.
Iris Clip IOLs
As for Prof. Dr. Sorcha Ni Dhubhghaill from Belgium, the iris claw lens is an excellent IOL to use in the absence of a capsular bag. As her Center performs a lot of complex explantation cases, she likes to offer the iris claw lens as an option to her patients.
She noted that of the 492 explantation cases performed in her center, 28% of them received the iris claw lens, of which 5% were anterior fixation and 23% were posterior fixation. “These were patients with sufficient iris tissue but insufficient capsular bag. Rigid and non-foldable, these lenses are made from polymethylmethacrylate (PMMA), which confers the rigidity needed to hold on to the iris,” she said.
For the iris claw lens power calculation, the A constant needed will be lower for anterior placement and higher for posterior placement. “It would be wise to double-check this before the operation as one can be too stressed during the surgery and choose the wrong lens,” she advised.
“The iris claw lenses are excellent as they are reliable, safe, dependable and technically simple, they have no issues with tilt and are known to be safe in children. But they need large incisions, are made of hard materials, need to have scleral tunnels, and you need to order them beforehand,” she said.
Scleral Fixation With or Without Sutures
Meanwhile, Dr. Mayank Nanavaty from the United Kingdom said that sutured scleral fixation of IOLs is a good option when other types of lenses are contraindicated, as he showed five surgical videos of the procedure.
After that, Dr. Scharioth Gabor from Germany presented surgical videos of sutureless intrascleral PCIOL haptic fixation, which he developed in 2006. The fixation of the haptics in a limbus-parallel scleral tunnel allows exact centration and provides axial stability of the PCIOL to prevent distortion. The technique is independent from iris changes and allows the use of standard PCIOL or special IOLs (multifocal or toric).
The next speaker, Dr. Vladimir Pfeifer from Slovenia, talked about the Yamane technique, a double needle flanged scleral fixation technique that has totally changed the way he approaches and handles IOL procedures.
He noted that the Yamane technique — the grand prize winner at the ASCRS 2016 Film Festival Awards — is a transconjunctival, sutureless approach. The technique involves the externalization of IOL haptics using 30- or 27-gauge needles through two transconjunctival sclerotomies. The haptics of the IOL are carefully laced into the lumen of the needles using intraocular forceps. Then the needles are used to externalize the haptics on the conjunctival surface. Finally, low-temperature cautery is used to make a flange at the end of the haptics before the haptics are pushed into the scleral to fix them in the posterior segment without capsular support.
According to Dr. Pfeifer, important things to take note of when performing this technique are being gentle when handling the haptics, carrying out vitrectomy before IOL implantation, and holding the Eckard forceps in a proper way.
The Carlevale IOL is also designed for sutureless scleral fixation. According to Dr. Mateo Forlini from Italy, this innovative 1-piece foldable IOL has shown good postoperative results and a reduction in surgical complexity.
“With this technique, IOL haptics are externalized and fixated within the sclera by using scleral flaps or limbus-parallel scleral tunnels. With this technique, there are lower risk of complications associated with suture degradation, scleral erosion and multiple passes through the sclera and uvea.
“The specific foldable design results in a low predisposition to optic plate tilt and haptic torsion. However, we need to carefully evaluate the sulcus-to-sulcus distance in long eyes preoperatively because the flexible structure of the IOL could be subjected to excessive stretching,” he noted.
Summing up the session, Chair Prof. Dr. Jorge L. Alio from Spain said: “The important thing when doing scleral fixation, is to have good patient selection, good IOL selection and proper skills, including vitrectomy skills. You need to train yourself.”
“All these techniques work well if they are done by people who are skilled in what they are doing and get good results. The problem is, people do a few (of the techniques), and they either don’t have the right care or enough experience, and they get complications. So, I think people got to choose their technique, watch the videos, learn how to do it and become skilled in it,” added co-chair Dr. David J. Spalton from the United Kingdom.
Editor’s Note: The 26th European Society of Cataract & Refractive Surgeons Winter Meeting (ESCRS Winter Meeting 2022) was held virtually from February 18-20, 2022. Reporting for this story took place during the event.
