This is our clinic's second Clareon Vivity case. We had planned to publish it a little sooner, but after surgery negative dysphotopsia (ND), one of the photic phenomena, occurred, and resolving it took time, which delayed publication.
She first visited us in October 2022 for consultation about cataract surgery. She had been referred by an acquaintance who had surgery at our clinic and wished for the same TECNIS Eyhance. She works as a conductor and reads scores, and also drives often, including at night, so she wanted to see as clearly as possible.
She had cataracts consisting mainly of dense cortical opacity, worse in the right eye, and corrected vision had fallen in line with her symptoms, so at her request she booked surgery for the end of January; we decided to determine the lens type and target distance during testing, centered on her preferred Eyhance.
Her score distance is about 70 cm, and she also wanted to see the faces of the orchestra members and the audience. With Eyhance aimed at 1.3 m (about −0.75 D), the 0.5 D add would, by calculation, reliably give vision to 1/(0.75 + 0.5) = 80 cm. At this refraction, however, seeing the expressions of distant members or the audience seemed difficult, and to fulfill her wishes with Eyhance, mini-monovision of about 0.75 D seemed essential.
When she came for the final visit just before surgery in January 2023, we told her the above and explained that Clareon Vivity, with an add of about 1.5 D, three times that of Eyhance, and halos and glare equivalent to a monofocal lens, would more likely give her the result she wanted. According to information at the time, early use of Vivity seemed likely to become possible in April, and when we told her so, she asked, if possible, to postpone surgery until then and have it with Vivity. Since it was an ordinary, non-urgent cataract, we rescheduled surgery for April as she wished.
With a 1.5 D add, even aiming exactly for distance, 1/1.5 = 67 cm can by calculation be seen reliably, so score distance is reliably covered. Her eyes were standard mildly myopic eyes with axial lengths in the 24 mm range, and her vision had originally been relatively good, so for the right eye we chose a lens targeting about −0.20 D, just short of becoming hyperopic. It was an ordinary age-related cataract without special features, so the cloudy lens was removed smoothly; we performed intraoperative wavefront aberrometry with the ORA system, which confirmed results almost the same as the preoperative formulas, so we inserted the lens of the planned power, and the surgery was completed without problems. Postoperative refraction was −0.125 D (1-month value), almost exactly on target, and uncorrected vision in the right eye improved to 1.5p distance / 0.7 near; she was satisfied with results matching the specifications.
Her wish to see at distance and at score distance had already been met, so for the left eye she wished for a target slightly toward near. Shifting too far toward near would cause light spreading from defocus when driving at night, making it harder to benefit from Vivity, so we operated with a somewhat conservative target of −0.42 D. Here too, postoperative refraction was on target at −0.375 D (1-month value), and she was satisfied with uncorrected vision of 1.5p distance / 0.8 near.
In the questionnaire at one month after surgery, she complained of being bothered by a dark crescent-shaped shadow on the temporal side of the left eye, so-called negative dysphotopsia (ND), thought to be due to the shadow of the edge of the intraocular lens; we decided to wait for it to resolve on its own and observed her. ND is by no means unusual for the first day to several days after surgery, and usually resolves spontaneously within about a month. Its exact cause is unknown, but it is thought to arise when, depending on how light enters the gap between the iris plane and the lens plane, the shadow of the lens edge is cast on the retina; it is classified as negative dysphotopsia when seen as dark and positive dysphotopsia when seen as bright. It is rarely a clinical problem and is usually just observed (the patient simply gets used to it), but reported treatments include exchanging for a larger lens so that light reaches the edge less, fixing the lens on top of the capsular bag (sulcus fixation) rather than inside it to reduce the gap between iris and lens, inserting another lens such as an add-on lens, and enlarging the anterior capsulotomy margin with a laser. In fact, I myself had never encountered ND severe enough to require an exchange. Recent reports also show that fixing the lens with its haptics horizontal significantly reduces ND, and our clinic fixes lenses horizontally unless there is a special reason, yet she still developed severe ND.
More than two months after surgery, the ND in her left eye still had not improved at all, and she said it was always visible and very bothersome, so we presented three options: (1) wait a little longer; (2) remove the Vivity and exchange it for a large 7 mm monofocal lens (ordinary lenses, including Vivity, are 6 mm); or (3) try reverse optic capture (ROC), moving only the Vivity's optic out of the capsular bag. Her symptoms were strong and intolerable, so she wanted something other than (1); since (2) could still be done if (3) did not resolve the problem, rather than removing the Vivity, she agreed to try (3), ROC, first.
Reverse optic capture (ROC) is a method of leaving the haptics inside the capsular bag while moving only the lens optic outside (on top of) the capsular bag and fixing it there. Ordinary optic capture, used with zonular weakness or posterior capsule rupture, fixes the haptics of a three-piece lens in the ciliary sulcus outside the bag and places only the optic inside the bag, hence "reverse" for the opposite.
More than two months had passed since surgery, but adhesion between the lens surface and the anterior capsulotomy margin was milder than expected and could be separated safely. In a lens exchange, the haptics would be separated next, but here the haptics stay inside the capsular bag and only the optic is moved outside the bag (onto the anterior capsule), so it is far less stressful than an exchange and can be done through a 1 mm corneal side port alone. In my experience, in lens exchanges, the tips of the haptics of Alcon lenses adhere strongly and are troublesome (perhaps this is why their toric lenses rotate less), but for ROC we want the haptics to stay in the bag, so the haptic tips adhering to the capsular equator actually seemed to help limit power deviation. (Incidentally, with J&J lenses, separating adhesions in the recess at the optic-haptic junction is troublesome.) The figure below is intraoperative. Before ROC, in the in-the-bag state, the blue arrows mark the anterior capsulotomy margin, and both optic and haptics are entirely in the bag; after ROC, the edge of the optic at the yellow arrows lies on top of the anterior capsulotomy, that is, outside the bag. Can you see that the anterior capsulotomy margin is under tension and has become slightly elongated horizontally? Incidentally, ROC itself is impossible if the capsulotomy is larger than the 6.0 mm lens diameter, and if it is too small, the margin is stressed and the risk increases, so I was truly glad that we always use an image-guided system and carefully create a 5.5 mm anterior capsulotomy without cutting corners.
ROC was completed without any problems; it is a simple, short, minimally invasive procedure, so we removed her eye patch on the same day. ROC is reported to improve ND in about 70% of cases, so I was worried, but about three hours after surgery she called to say, "The shadow is gone!" and I was relieved. Not everything was good, however: with ROC the lens moves forward toward the cornea, changing refraction toward myopia, so distance vision falls. With ordinary sulcus fixation, depending on lens power, the myopic shift is about 0.7–0.8 D. With ROC, where the haptics are in the bag, I expected it to be smaller, and in the end the shift was only 0.5 D toward myopia. As a result, uncorrected distance vision fell from 1.2 to 0.9 after ROC and then recovered to 1.0, while near vision improved from 0.8 to 1.2p. Her right eye sees well at 1.5p distance, so in binocular vision there was no loss of distance vision; rather, near vision improved and the ND resolved, and she was delighted with the result. We also told her that the lens could be exchanged for one whose power compensates for the myopic shift from ROC, but fortunately she felt that seeing her smartphone clearly without glasses was a bigger benefit than the loss of distance vision, and did not wish for an exchange.
ND is often handled with "you'll just have to get used to it; let's wait," and in fact it often resolves on its own; I too used to handle it that way. This time, however, the patient told us: "The shadow was really annoying. Troubled by it, I searched the internet a lot, and I think many people are putting up with it on the explanation that it will stop bothering them eventually, so please help people like that." There may have been a better solution, but we have published this as one way of dealing with ND. In particular, if a refractive change can be accepted, as in her case, the multifocal lens's function can be preserved, and, for example, as a rescue for people with a hyperopic shift, this method seems far simpler, quicker, less invasive and more economical than an add-on lens or exchange surgery.
Finally, regarding Vivity: we often see uncorrected vision change during the postoperative course even though objective refraction does not change at all, yet when we ask, most patients seem unaware of it. Vision may change with the proportion of the pupil occupied by the central wavefront-shaping zone, and it may take a little time to get used to. In Case #77, too, near vision in the left eye had improved to 0.9 by two months after surgery, so I feel that, if conditions allow, it may be fine to leave time between the two eyes; we will continue to update.
*Please note that ND is unrelated to Vivity itself; it is mainly caused by structural characteristics of the patient's eye, as described above, and can basically occur with any lens.
2023.7.26