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25. Kongress der DGII 2011
Abstracts DGII 2011
VIX.
Wissenschaftliche
Sitzung:
Linsentechnologie und Astigmatismus
69 R
Marie Josée Tassignon (Edegem/Belgien)
Importance of IOL alignment on refractive outcome
Most phakic eyes do not have significant lens tilt or decentration; however, pseudophakic eyes are different. At the moment
of implantation, the IOL may be perfectly centered along the line of sight and assume the physiological tilt of the capsular
bag, which is essentially the best postoperative situation for which any surgeon can hope. But after the IOL is implanted it
comes into contact with residual lens epithelial cells (LECs) on the capsular bag, and a strong immune reaction flares up, causing
the LECs to start proliferating and differentiating.
The visual consequences of this reaction depend greatly on its severity, which can range from a few scattered clusters of LECs
to strong anterior capsular contraction combined with posterior capsule opacification (PCO). The former will not result in significant
visual effects for the patient; the latter will cause displacement of the IOL, resulting in considerable reduction in visual
acuity and contrast sensitivity and an increase in glare effects.
Currently, we are unable to predict how strongly residual LECs will respond to the presence of an IOL. Although certain choices
in lens material and edge designs can help reduce the effects of LEC reaction, an undesired lens dislocation is still a possibility
for any in-the-bag IOL design, causing the lens to move to a suboptimal position and resulting in suboptimal vision
quality.
For this reason, our department introduced the Morcher 89A Bag-in-the-Lens (BIL; Morcher GmbH, Stuttgart, Germany) IOL,
which requires both anterior and posterior capsulorhexes for implantation. The edges of both capsulorhexes are positioned
into a groove between two flat elliptical haptics, much as a bicycle tire is put into the rim of a wheel. This moves the LECs
away from the optical zone to an area where they can do no harm, resulting in a 0 % PCO rate. Moreover, the double rhexis
method causes the BiL to assume the physiological tilt of the capsular bag and to have good postoperative rotational1 and
translational stability.2 This stability recently gave us the confidence to successfully introduce a toric version of the BiL. This
experience suggests that the BiL is an ideal platform to implement many of the innovations described above without having
to worry about undesired postoperative IOL repositioning.
1Rozema JJ, Gobin L, Verbruggen K, Tassignon MJ (2009). Changes in rotation after implantation of a bag-in-the-lens intraocular lens. J Cataract Refract Surg. 35, 1385-1388
2Verbruggen KHM, Rozema JJ, Gobin L, Coeckelbergh T, De Groot V, Tassignon MJ (2007). Intraocular lens centration and visual outcomes after bag-in-the-lens implantation. J Cataract Refract Surg. 33, 1267-1272
Erschienen in: german medical science
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