[Duet procedure to achieve reversible trifocality].

The functional results and the occurrence of side effects (especially photic phenomena) for multifocal intraocular lenses (IOL) are difficult to predict. Furthermore, in the course of life patients can develop diseases in which a multifocal optic would be a disadvantage. In these cases exchange of the IOL is the only treatment option. Implantation of a monofocal or monofocal toric IOL in the capsular bag and a supplementary trifocal IOL in the ciliary sulcus in a single operation, known as a duet procedure, provides trifocality that can be easily reversed if necessary.