Product Watch: The LISA lens

Since its introduction, LISA has developed into a strong choice for patients with refractive challenges whether associated with cataract or with a clear lens. The IOL’s name is an acronym that stands for Light distribution (65% far and 35% near), Independence from pupil diameter, Smooth refractive/diffractive surface profile and Aberration-correcting optic. LISA, both in its regular as well as in its toric version, is designed to be used in coaxial or bimanual microincision cataract surgery (Co-MICS or Bi-MICS). The incision size for that procedure has shrunk to 1.5 mm, down to, until only recently, an unimaginably small incision size. This microincision, watertight and generally bloodless, almost guarantees astigmatism neutrality, the prevention of endothelial cell loss and an extremely low risk of postoperative infection.

High astigmatism can be corrected
The AT.LISA toric lens is so far the only toric IOL that can be used for true microincision surgery. Surgeons, some of them using AT.LISA toric for a considerable time now, have noticed the overall stability of the lens once it is put in place — a stability that is vital to the procedure's success in patients with a significant preoperative degree of astigmatism. This rotation stability has recently been demonstrated in a study that found a mean rotation of the IOL platform of only 2° one year after surgery. AT.LISA toric has two completely different surfaces. The aspheric anterior optic is toric for astigmatism correction. AT.LISA toric is calculated individually for every patient to provide the optimal post-operative refractive results. The cylinder correction range is so broad — up to 12 cylindric dioptres — that the IOL is suitable for the vast majority of patients with astigmatism. The aspheric posterior surface of the lens comes with a high-tech diffractive/refractive optic design that covers the entire optical surface for optimal imaging quality, thus providing the premise for excellent post-operative refractive results with a low rate of photic phenomena.

AT.LISA 366D comes with a standard refractive power between 0.0 and +32 dioptres. Its 65/35 light distribution has been proven to greatly reduce halos and glare while at the same time improving intermediate vision — essential for people working with computers. Its efficacy, even for patients with an extraordinary high hyperopia, has, as recently as May 2009, been analysed. In a Spanish study comprising 170 eyes of 85 individuals, those patients achieved a satisfactory full-range of vision comparable with that obtained in patients with low to moderate hyperopia (Fernández-Vega, Am J Ophthalmol, epub ahead of print). A different study, published in November 2008, demonstrated a better intermediate visual acuity in myopic patients than those who received a competitive spherical MIOL, Alcon's AcrySof ReSTOR (Alfonso, J Cataract Refract Surg 34: 1848-1854). Even 'supervision' is nothing exceptional — in a study by Kaymak, published in 2007, the average BCVA of 20 patients who underwent bilateral implantation of AT.LISA reached 1.175 (decimal) (Ophthalmologe 2007;104:1046-51). Another study on 18 patients even demonstrated an uncorrected mean visual acuity of 1.13 (decimal) in 18 patients with bilateral AT.LISA (presented at the DOG meeting 2008 in Berlin, Germany). One patient at the Mainfranken Centre with an AT.LISA 366 had a visual acuity of 2,0 (decimal).

The pseudo-accommodation range that can be achieved with an AT.LISA is up to 5 dioptres. That gives the IOL the potential to satisfy a desire commonly voiced by patients when they decide to have an operation: to lead a life with only a minimal need for glasses or without glasses at all.