Recover Clear Vision at Far and Near
In our busy, multi-tasking world, we want to — need to — see perfectly at many different distances. We all read, use cell phones, tablet devices, desktop computers. We read newspapers, magazines, books, and the tiny print on prescription medication bottles when necessary. We enjoy athletic pursuits and sports, most of which benefit from exceptional vision at far distance. When we drive, we want to see freeway signs hundreds of yards away, and our dashboard, and occasionally check email or texts on our phones (OK, when we’re stopped, or parked, officer :->).
So as good as monofocal IOLs may be, they’re not close to a perfect solution. We still have not developed the perfect, adjustable-focus IOL to replace the natural young human lens, but multifocal IOLs add a whole set of features and benefits that are not possible with monofocal IOLs.
Multifocal IOLs work by having concentric zones of different focus, alternating far and near. This affords very good distance and reading clarity. These lenses do need to optically split the incoming light into two points of focus, so they do cause some reduction in contrast sensitivity (fine detail detection in low light). And the concentric rings do cause a bit of halo to be perceived around point sources of light at night such as headlights, taillights and street lights. The overwhelming majority of people that have had multifocal IOLs implanted are extremely happy with their overall visual function, and don’t mind these imperfections, which they perceive to be minor. Whether you will be an optimal candidate for multifocal IOL care will be assessed and discussed at your comprehensive cataract and IOL consultation.
The Tecnis Multifocal IOL is designed to afford very good focus at both distance and near. Nearly 9 out of 10 patients are able to enjoy a glasses-free vision after they receive the Tecnis Multifocal IOL.
The Tecnis Multifocal has its multifocal optic on the rear lens surface. By comparison, The ReSTOR (see below) is designed with its multifocal optic on the front IOL surface.
The ReSTOR lens has a design similar to single-focus lenses. The difference is that the center section of the front optical surface has concentric rings of differing focus, alternating for distance and near, as shown in images at right and below. Outside the zone of alternating rings, sharp distance vision is provided by the peripheral portion of the lens, like the upper part of a bifocal. The very center of the lens is tuned for near clarity, like the reading portion of a bifocal. The multiple concentric rings effect a much broader range of focus than a monofocal IOL, through both refractive and diffractive optics.
The ReSTOR lens incorporates aspheric optics for optimized distance viewing, and night driving clarity; and has an effective “add” (reading range correction) that is well-suited to common near vision tasks.
With any combination of a particular product (like a lens implant) and a service (like lens implantation surgery and refractive services) there is a wide range of information available. Some of the information is accurate, some is inaccurate, and some is anecdotal. The anecdotal category is typically difficult to evaluate.
Dr. David Wallace is a highly skilled lens implant surgeon. He has treated many Los Angeles cataract patients. He has treated many cataract patients, as well as those seeking clear lens replacements.