The loss of confidence in bimanual microincision surgery over the years has caused many surgeons to seek an alternative approach that balances the advantages of minimally invasive cataract surgery with the safety of a sleeved tip. The hunt is also still on for a multifocal lens that offers good vision across all distances, coupled with a low incidence of side effects.

In short...

Ultimately, every cataract surgeon is looking for a safe method of performing microincision cataract surgery (MICS) and they are also seeking a lens that offers patients spectacle independence, good contrast sensitivity and as few side effects as possible. Dr Detlev Breyer, owner and surgeon at ZeitzBreyer-Augenheilkunde an den Schadow Arkaden in Dusseldorf, Germany, thinks he's found the answer.

"I began to lose confidence in multifocal IOL technology because of the pupil dependence associated with these lenses, light loss between near and distance points, increased likelihood of decentrations, and low spectacle independence. That was until I attended an Acri.Tec symposium two years ago," said Dr Breyer. He continued, "My suspicions were confirmed by my American colleagues, when an ASCRS survey in 2003 based on practice styles and preferences showed a significant loss of interest in multifocal lens technology between 1989, when 15% of surgeons reported having no interest in multifocal lenses, and 2002 when this had risen to 36%."

Finding the right lens

Figure 1: Acri.LISA Toric 466TD.

Dr Breyer conceded that multifocal lenses afforded several advantages, however, he felt that the disadvantages outweighed the positives. His confidence has, however, been renewed by Acri.Tec's Acri.Smart IOLs. In particular, the newest member of the family, the non-astigmatism inducing MICS IOL Acri.LISA Toric 466TD (Figure 1) represents a new concept in IOL design.

LISA is an acronym for light intensity distribution in 65% far and 35% near (L); independent from pupil size (I); smooth refractive/diffractive surface profile (S); and aberration corrected (optimized aspheric optic) (A).

"Having heard several presentations about this lens, I felt confident that this was different. This IOL was shown to provide good distance and near visual acuity and better intermediate acuity than any other multifocal I had seen. Its use was also associated with less night haloes, better spectacle independence and excellent patient satisfaction rates, " noted Dr Breyer.

When speaking generally of multifocal lens implantation, Dr Breyer advised that surgeons still err on the side of caution. "If you are considering implanting a multifocal IOL, it is essential that thorough biometry and postoperative refraction analysis be performed. The correct IOL needs to be selected that suits the patient's lifestyle and there must be a good level of understanding on the patient's part as to what this procedure entails. The patient needs to know what to expect of their vision postoperatively and they must be aware that their vision may take some time to reach peak levels because of neuronal adaptation," insisted Dr Breyer.

He referred to an award-winning study that was presented by Dr Hakan Kaymak at the 2007 ASCRS congress, which examined visual quality post multifocal IOL implantation. The study showed that vision gradually improved over a period of several months, however, this period of neuronal adaptation could be significantly shortened if a computer-based visual training programme was implemented over a two-week period.