Two approaches may offer a clinically working solution: Although many surgeons report satisfying-to-excellent results with both lenses, thorough clinical studies revealed only limited accommodative power, which is insufficient to achieve spectacle independence in most patients. New accommodating IOL concepts eg, the dual-optic Synchrony [Visiogen, Irvine, Calif] are promising, however, are still under clinical investigation. Implantation of a multifocal IOL is the second approach to achieve spectacle independence in our patients.
This lens was restricted by some drawbacks ie, limited near vision; reduced contrast vision, particularly under mesopic lighting conditions; and photic phenomena including halos and glare. In contrast to the five refractive optical zones of the Array, the diffractive optic design of the E multifocal IOL Pharmacia, Uppsala, Sweden performed better. This prevented the use of this IOL in a greater number of patients.
All of these multifocal IOLs use a diffractive optic design. With application of a diffractive or combined refractive-diffractive optic, the visual performance of these new multifocal IOLs became independent of the pupil size, which was one significant drawback of the Array.
The apodized design of the Restor lens even results in an improved distance vision with increasing pupil size. The introduction of an aspheric lens design is one major advancement in image quality, and it has been proven to increase contrast sensitivity in monofocal lenses.
We compared the Tecnis MF to the Array in 50 patients eyes. Patients also experienced greater spectacle independence with the Tecnis lens Another aim of the AcriLISA system is to reduce the well-known side effects associated with multifocal IOLs, particularly halos, by producing one dominant and one weaker image. Furthermore, smooth steps between the diffractive zones were engineered to reduce glare.
Our investigations showed excellent distance visual acuity and good near vision under photopic lighting conditions with significantly better results tested binocularly Figure 2.
Intermediate visual acuity was also good, as the pseudoaccommodation range was 5. Our results with the Tecnis MF and AcriLISA, two of the new multifocal IOL generation lenses, demonstrated significant improvements in visual function, spectacle independence, and patient satisfaction compared with previous models.
Some reduction of contrast sensitivity and the persistence of photic phenomena remain when compared with monofocal IOLs, but there is less subjective impairment.
Our investigation showed an increase of visual acuity, even between 3 and 6 months after surgery Figure 4. Patient selection is crucial. Excluding patients with high demand for contrast vision, we achieved a high patient satisfaction with these new multifocal IOLs.
Therefore, in patients who want to be independent from spectacles, I prefer multifocal IOLs instead of accommodating lenses due to their uncertain and insufficient efficacy. Professor Mester did not provide financial disclosure information. He may be reached at sek-augen kksulzbach. Early results with the 1CU accommodating intraocular lens. J Cataract Refract Surg. Pilocarpine-induced shift of an accommodating intraocular lens: Changes of the accommodative amplitude and the anterior chamber depth after implantation of an accommodative intraocular lens.
Graefe's Arch Clin Exp Ophthalmol. Reading performance with a refractive multifocal and a diffractive bifocal intraocular lens. Impact of a modified optic design on visual function: I use the Crystalens in patients who desire near and intermediate vision and clarity of distance vision.
Currently, I use all of the refractive lenses that are available in the United States. As they differ in function and have various strengths and weaknesses, all three lenses are useful to me and my colleagues.
The accepted treatment goals for accommodating lenses include three indications: As surgeons, we must juggle all three indications on a case-by-case basis to find the right lens. For example, a patient may have a high degree of nearsightedness or farsightedness but less of a cataract. A younger noncataractous individual would not necessarily receive one of these IOLs.
With multifocal IOLs, the light is split and focused at different points due to the concentric zones. The implantation of the Crystalens is straightforward and it is one of the fastest lenses to implant. The surgery does require need a watertight wound, meticulous cortical clean-up and a precise capsulorhexis, but these are advantages for any cataract surgery.
In some patients, multifocals may provide better near vision. For instance, a patient with only one eye implanted with a Crystalens may not have the same rate of acheiving J1 as another patient with one eye implanted with a multifocal. When you look at binocular vision in patients implanted binocularly, however, the patients may be similar in their abilities to read up close.
This is achieved by providing a bit of monovision in the nondominant eye of the patient with the Crystalens. In fact, according to the FDA clinical trials, a high percentage of patients implanted bilaterally with Crystalens Typically, these results are rapid and actually improve over time. At our practice, we use the Acrysof Restor, the Rezoom, and the Crystalens, and the majority of the feedback has been encouraging.
Our patients who report the smallest amount of negative feedback regarding overall vision, though, have been those who received the Crystalens. In our experience, more patients complain about glare and halos with multifocals than with the Crystalens. Results from FDA trials demonstrated similar findings concerning the increased inducement of glare and halos with multifocals as well. In general, if the patient needs good J1 near vision, my colleagues and I lean toward implanting the Acrysof Restor.
If there has been a rupture in the posterior capsule or a tear in the anterior capsule, or if there is zonular weakness, a multifocal may, again, be a better option. Additionally, the multifocals are the only choice for sulcus implantation. If it is a patient who needs more of a bifocal effect, we look at multifocals. We choose the Crystalens for patients who desire more intermediate vision and the clarity of the distance vision. The Crystalens offers excellent quality of vision and is often our choice for more active patients.
Intermediate vision is important to most patients today considering the high levels of cell phone, computer and PDA usage. Not only does patient selection play a role, but it is necessary to perform careful individual eye assessments.
In certain cases, it may be appropriate to mix accommodating and multifocal IOLs in order to achieve the optimal result.
In contrast, a monofocal lens remains the best solution for some patients. Additionally, Eyeonics is working on various improvements that it will plan to integrate into its Crystalens technology, with the aim of increasing accommodation and further improving the quality of near vision.
With these advancements, accommodating lenses will surely be an option for many surgeons and patients. He states that he has consulted for Eyeonics. Slade may be reached at sgs visiontexas. Advertisement - Issue Continues Below.