Six months earlier, a health check-up had suggested cataracts, and another eye clinic diagnosed them. He then first visited us without a referral letter, wishing to have surgery at our clinic.
Nuclear hardness was about 1.0 in both eyes, but he had cortical cataracts with anterior capsule fibrosis; in the left eye the pupillary area was almost completely white, with some dense localized opacity inferiorly, and the glare made it difficult even to keep his eyes open during examination.
In this state, refraction testing cannot be performed accurately either; as shown below, refraction readings came out sometimes hyperopic and sometimes myopic, and could not be trusted at all.
His age and the cataract type made it clear that these were not ordinary age-related cataracts, and when we asked, he said he had a history of trauma from a tennis ball to the left eye in junior high school. There may have been a traumatic element, but the right eye already had similar anterior subcapsular opacity, making it bilateral, so systemic involvement was also possible, though he said he did not have atopic dermatitis. In any case, they did not seem to be ordinary cataracts, so privately I hoped he would choose monofocal lenses to be safe, but he said, "Golf is my hobby and I drive about once a month, but I work in accounting, so I want to see fine print and the computer well," and he wished for multifocal lenses...
Axial length was long in both eyes, over 26 mm, yet he was not highly myopic, only mildly myopic at about −1.5 D. Reviewing the test results, besides the cataract type, the reason the myopia was canceled out was that his corneal power was 41 D, a rather flat cornea (the average is 43 D).
In people like him whose eyes do not have standard proportions, postoperative refractive error is also more likely in lens power calculation, so surgery with multifocal lenses, which require hitting exact distance focus, is quite difficult.
However, saying "my mother had surgery with bifocal lenses," he was firmly set on multifocal lenses. In candidacy testing, corneal higher-order aberrations on the OPD-Scan were low, and there was no obvious glaucoma or macular disease, so, unfortunately(?), we found no reason to avoid multifocal lenses. He wanted to do golf at distance and the computer at work without glasses, and being of above-average height, not small, his desired near distance was not too close, so we proceeded with surgery using Clareon PanOptix, in which he was also interested.
In cataract surgery with such anterior capsule fibrosis, I consider the risk to increase if fibrosis extends onto the line of the anterior capsulotomy, but in his case there happened to be a conveniently fibrosis-free area right around the central 5.5 mm (blue circle above), so we were able to perform the anterior capsulotomy safely under the VERION image-guided system (blue triangle). We strive to make accurate anterior capsulotomies in both size and shape using digital guidance; an advantage of femtosecond laser-assisted cataract surgery (FLACS) is that this step is done by laser, creating a perfectly round capsulotomy. In that respect my manual surgery certainly loses to the laser's precision, but at present this is not thought to lead to differences in postoperative vision.
The inferior opacity was also separated and removed safely without damaging the capsular bag, and to avoid refractive error we performed intraoperative wavefront aberrometry with the ORA system to decide the lens power. Given the flat cornea, even considering the risk of becoming hyperopic, the calculation from preoperative data on the left of the figure below suggested 14.5 D, but the intraoperative wavefront result on the right predicted a postoperative refraction of 0.00 D with 14.5 D. From experience, we judged that this carried a high risk of hyperopia and chose a 15.0 D lens, 0.5 D stronger (predicted postoperative refraction −0.32 D).
Finally, so that the multifocal lens could function properly, we carefully aligned the center of the lens and finished the surgery.
After surgery, the refractive error we had feared did not occur; refraction came out at exactly zero, and he was delighted with very good uncorrected vision of 1.5 distance / 1.2 near. Had we not performed intraoperative wavefront aberrometry with the ORA system, we would probably have used 14.5 D and he would have become hyperopic, so this time the ORA system helped us.
Anterior capsule fibrosis in the right eye was not as advanced as in the left, but preoperative corrected vision had fallen to 0.6, so he wished to proceed with surgery as planned. The right eye had mild against-the-rule corneal astigmatism, so we operated using the toric Clareon PanOptix Toric, and, as with the left eye, used the ORA system for lens power selection and axis adjustment. After surgery he achieved good uncorrected vision of 1.5 distance / 1.2 near, and he was very satisfied that he could see both golf and the small figures at work well without glasses.
Incidentally, several accountants have chosen multifocal lens surgery at our clinic, and for some reason all the men chose PanOptix and the women TECNIS Synergy. I suspect that men, many being active in driving and golf, tend to choose PanOptix because they prioritize distance vision, while women more often choose TECNIS Synergy, perhaps because, owing to height (arm length), their desired near distance is closer than men's, or because they value near distances for things like cooking.
Finally, the changes in the optic disc in the fundus photo above might suggest glaucoma; the figure below shows his OCT results for the nerve fiber layer before and after surgery. Weighing the preoperative results on the left, there are many red areas where the nerve fibers are thinned, and one might judge that, with a glaucoma risk, he was not a candidate for multifocal lenses. But in the postoperative results on the right, the red thinned areas have disappeared and the result is almost normal. The nerve fiber layer cannot recover and thicken after cataract surgery, so the preoperative results mean that OCT's near-infrared signal was attenuated by the dense cataract, measuring worse than the true result. Thus cataracts can make accurate diagnosis of fundus disease difficult and risk preventing appropriate treatment, so we recommend having surgery at the appropriate time rather than putting up with them too long. Also, as for multifocal candidacy, it must of course be judged comprehensively from multiple tests, such as visual field testing, but artifacts of measuring devices like this also seem to need consideration, so if you are unsure about lens choice, please feel free to consult us.
2022.12.18