S. Behrendt et al., SANDWICH-LENS INTRAOCULAR IMPLANT - A CON CEPT FOR CORRECTION OF APHAKIA IN INFANTS, Klinische Monatsblatter fur Augenheilkunde, 207(1), 1995, pp. 42-45
Background In the management of congenital cataracts the correction of
aphakia is still an unsatisfactorily solved problem. As far as surgic
al techniques and materials are concerned, the implantation of an IOL
seems to be justified even in younger children; but choosing the refra
ctive power of the lens is somewhat difficult regarding the expected g
rowth of the eye. Materials and methods A new type of IOL is presented
as a solution for this problem. Being composed of a PMMA-fashioned op
tic and haptic it bears a silicone lens which is fastened on top of it
. The supporting lens is made of PMMA (polymethylmethacrylate) with a
biconvex surface with modified J-loops. The diameter of the optic is 6
mm, the overall diameter is 11 mm. The supplementary lens is made of
the same silicone material as used for foldable intraocular lenses. It
s diameter is 4.5 mm. This additional component can be removed from th
e implanted lens so that the needed reduction of refractive power afte
r completed growth of the eye can be performed. The PMMA-fashioned bas
ic component remains in situ just like a conventional posterior chambe
r lens. The lens was examined using scanning-electron microscopy. Im-
and explantation was performed in isolated porcine eyes. Results The h
igh quality of the lens could be demonstrated using scanning-electron
microscopy. The technical feasibility of this concept could be demonst
rated on isolated porcine eyes. Discussion Currently the sandwich lens
is being tested in animal experiments. Our special interest is focuss
ed on biocompatibility, formation of secondary cataract, biological re
actions in the interface and the possibility of atraumatic explantatio
n of the silicone lens.