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25. Kongress der DGII 2011
Abstracts DGII 2011
VII.
Wissenschaftliche
Sitzung:
Live-OP-Kurs
54 R
Marie Josée Tassignon (Edegem/Belgien)
"Bag in the lens" and additive multifocal IOL
Todays cataract surgery is no longer simply extraction of the lens content and implantation of a spherical IOL. The surgeons
can now make their choices between more complex optics IOLs which may better meet their patients expectactions. The number
of patients expecting to function without spectacles at all distances after uneventful cataract extraction is steadily
increasing the last years.
This introduction sounds directly borrowed from the marketing and while some surgeons claim a 100 % success, others warn to be very careful in "choosing the patients" who will be ideal candidates for these complex optics IOLs. However, the eligibility criteria remain vague and in case of unsatisfied patients, the surgeons blame this dissatisfaction on poor "brain plasticity". The surgeons who are prudent (realistic) will state that "the patient should be informed preoperatively that there is no absolute guarantee of spectacle freedom". Their message is that patient selection, informed consent and realistic expectations are important for a successful postoperative result. Why do these complex optics introduce new concepts like "brain education", "realistic expectation", and "patient selection"? The 21st century also introduced a new group of IOLs called "premium IOLs". Also this term is vague and comprises aspheric, toric, diffractive, refractive multifocals and accommodating IOLs. The principal limitation of the aspheric IOLs is the lack in full compensation of the corneal curvature. Concerning the toric IOLs, the limitation relies mainly in the precise correction of the corneal astigmatism axis. The diffractive, refractive or combined diffractive-refractive IOLs present an additional degree of difficulty related to pupil dynamics, which is more sensitive for IOL decentration. After cataract surgery the pupil diameter will reduce, at far and at near. The central area of multifocal lenses are located in the geometrical center of the lens. The questions that now raises is whether that geometrical center corresponds to the center of the entrance pupil of the eye once the multifocal IOL is located in the capsular bag. Another question that needs to be addressed is whether PCO will cause active displacement of the IOL over time. The answer is clearly yes.
All the above factors will ultimately bear on patient satisfaction. Geometrical decentration will result in immediate postoperative visual complaints while PCO will cause visual related dysfunction later on. These are all reasons why my preferred approach up till now is to work with a removable additional diffractive/refractive IOL in combination with the bag-in-the-lens, which approach allows me to easily correct postoperative patient's complaints of glare or chromatic aberrations due to possible misalignment issues.
Erschienen in: german medical science
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