Case #30: Man in his 60s from Yokohama, Kanagawa (blended vision: extended depth of focus multifocal lens TECNIS Symfony)

He had had cataract surgery on his right eye with a multifocal lens at a university hospital, and was referred to us wishing to have the left eye done. The right eye had been operated on the previous year with the bifocal TECNIS Multifocal with a +4 D add (for near at about 30 cm). Uncorrected vision was very good at 1.5 distance / 1.0 near, and he was satisfied, especially that he could see things at hand well, but intermediate distances of about 1 m were a little blurry. He also does photography, so, although it is a different type of multifocal lens, we proposed TECNIS Symfony for the left eye, which has little loss of contrast sensitivity and sees well from intermediate to distance. Symfony is a diffractive multifocal lens on the same platform as the right eye's TECNIS Multifocal, but it is an extended depth of focus lens rather than bifocal.
Briefly, their characteristics are: "bifocal lenses give good near vision but are weak at intermediate distances and tend to reduce contrast sensitivity," and "extended depth of focus lenses are weak at near but good from intermediate to distance, with fewer halos and glare and little loss of contrast sensitivity." Using different types of multifocal lenses in the two eyes like this, so that each lens compensates for the other's weak points, is called blended vision, and reports of its use at meetings have increased in recent years.
When we explained these characteristics, he too wished for Symfony in the left eye; the surgery was completed without problems, and he was very satisfied with good postoperative uncorrected vision of 1.2 distance / 0.9 near. When we asked after surgery which eye felt better, he said the left eye with Symfony saw more clearly. This time it was blended vision with Symfony and a bifocal with a +4 D add, but another patient comparing it with a +3.25 D add (for near at about 40 cm) also said Symfony saw better. This is probably because Symfony has a small light energy loss of 8% (18% for TECNIS Multifocal) and good contrast sensitivity.
Modern medicine has no lens that sees everything from far to near, but we will propose lens choices that make use of each multifocal lens's characteristics to come as close as possible to your wishes, so please feel free to consult us.