Caption figure 1:
3-D OCT projection of an fs laser membrane cut (symbolic laser focus in red).
The membrane in
blue is only 300 µm from the prepared porcine retina in brown.
Individual images
from the middle show the geometry. Illustration: LZH
(September 17, 2015) Several
laser-based operations are already established for correcting defective vision.
However, this highly precise and yet gentle method cannot be used yet for
presbyopia and for adhesions on the retina. In the project IKARUS the Laser
Zentrum Hannover e.V. (LZH) and four project partners have combined femtosecond
laser technology with optical coherence tomography (OCT) as well as adaptive
optics, to expand the range of laser surgery.
In the established femtosecond laser-assisted in situ
keratomileusis (fs LASIK), the cornea is cut open using the laser to
subsequently correct the defective vision. In order to treat presbyopia
however, the tissue has to be cut deeper. The scientists at the LZH and their
industrial partners use an fs laser for precisely cutting the lens, creating
slip planes and thus making the lens more flexible.
Cutting the eye lens
with the laser, without damage
This treatment becomes only possible through an effective
visualization of the eye tissue. For this, the Image Guided Laser Surgery Group
of the Biomedical Optics Department of the LZH has adapted an OCT imaging unit
from the ROWIAK GmbH. With this and a special software it is possible to image
the cutting of the eye as well as the laser beam delivery during the operation.
Within the project cuts into the eye have already been done without damaging
neither the front nor the rear part of the lens capsule. In current clinical
studies, the ROWIAK GmbH is further examining this process.