Multifocals: Careful pre-op preparation minimises explantation

Careful patient selection and precise biometry will all help minimise the risk of later explantation of multifocal IOLs, Dr Risto Uusitalo of the Helsinki Eye Clinic said.

"There is a stacking effect, where a number of small errors stack up into a large error. That is why it is vital to get precise biometry, and select appropriate patients," explained Dr Uusitalo.

Exclusion criteria include astigmatism greater than 1.0 D, pre-existing ocular pathology, such as very dense cataract where you can't see the fundus properly, and previous refractive procedure. Physical data is not enough, assessing the psychological profile is also vital.

"A teacher once told me, if your patient has more than three pens in his pocket, be careful. They are typically physicians, architects, engineers and artists. They are perfectionists, they have unrealistic expectations and they are less likely to be happy with loss in vision quality," Dr Uusitalo said.

Similarly, professions that depend on the quality of vision should be excluded too, for example truck drivers.

Dr Uusitalo concluded that multifocal IOLs pose some risks that cannot be ignored, these can, however, be reduced and, overall, the benefits outweigh the risk, for the right patient.