"It has been my opinion for many years that multifocality in cataract surgery is highly underused," remarked Dr Serge Zaluski (Centre VISIS, Perpignan, France) when describing his initial reasons for performing a study using a multifocal lens in cataract patients presented at this year's ESCRS meeting in Paris.

He continued that the proportion of multifocal lenses implanted in France is a mere 5% or less, which he stated could or should be more than 30% of eyes. "Considering these facts it is important to me to let ophthalmic surgeons know there is a variety of efficient multifocal lenses available," he emphasized.

Deciding on the lens

Figure 1(a): The uncorrected and best-corrected visual acuity results for distance vision.

For years Dr Zaluski had been searching for a multifocal lens that could not only offer his patients good near and distance vision but also intermediate vision. Having seen positive results reported with the Diffractiva Diff-s lens (HumanOptics, Erlangen, Germany) he chose to implant the lens himself in his eligible cataract patients.

Figure 1(b): The mean uncorrected and distance corrected near visual acuity results.

"My opinion is that a 3-piece IOL (with square edged optics) is one of the best choices for 'in the bag stability' and avoiding PCO," said Dr Zaluski. "Moreover, the price of the lens, in France, makes it affordable for many patients."

The Diffractiva Diff-s IOL is a foldable diffractive 3-piece multifocal lens that was CE marked in 2007. It has been made using a hydrophobic MicroSil optic and features a 360º sharp optic edge to prevent PCO, UV inhibitor as well as aspheric anterior surface. It can be injected through a 2.8 mm incision and is available with a blue light filter. "Presently, this lens represents an accomplished model of a diffractive multifocal lens," added Dr Zaluski.

Figure 1(c): The mean uncorrected and distance corrected intermediate visual acuity results.

In Dr Zaluski's opinion silicon is a very good material for use with multifocal IOLs, however, it has not proven to be popular. A 3-piece design is also not as well received as a 1-piece design, especially amongst younger ophthalmologists, because there is a learning curve associated with its implantation.

The study

The aim of the study presented by Dr Zaluski was to determine the visual performance and patient satisfaction with the Diff-s MIOL. There were a total of 129 patients (258 eyes) in the study group with senile bilateral cataract. Patients were not enrolled in the study if their post-op astigmatism was expected to be greater than 1.25 D.

The lens was implanted through a 2.8 mm incision. Follow-up involved examination of the patient's visual acuity at 1–6 months post-op and PCO for the final follow-up session. All the patients were asked to complete a questionnaire 3 months after their operations to determine the level of satisfaction and quality of life improvements afforded by the lens.