Ocular IVS2, Product Manual

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25
Technique – OLIV-WFNA, OLIV-EQNA
The lens may be held on the eye by an assistant using the
Landers Lens Handle (OLIV-H) or by suturing one of the
Landers Lens Rings to the sclera.
After a suitable wetting agent is placed on the cornea, the
lens is placed on the cornea.
Many surgeons do not use an inverted image contact lens until the anterior third of the vitreous has been
removed and a deeper image of the vitreous cannot be obtained with normal microscope observation.
Turn off the coaxial and oblique illumination of the microscope, since this may lead to reflections from
the contact lens surfaces. Check the positions of instruments repeatedly before and during the operation,
as it is very difficult to recognize the patient’s crystalline lens through a contact lens.
In order to focus the microscope, set it to its lowest magnification and then raise the microscope head
away from the patient’s eye. It is suggested that one work at the lowest magnification. Most surgeons
reduce magnification after they become familiar with the IVS so they may achieve more field of view.
Be sure the lens is seated well on the cornea. If the assistant has a poor image and you find the image
good (or vice versa), it is possible only one observation beam path of the microscope is receiving and
transmitting a good image. Slightly shifting the lens will correct the problem
You can bring the pars plana into view by tilting the contact lens a little or by shifting it horizontally.
Some lenses possess large depth of field. The concavity of the fundus then appears slightly flattened,
especially toward the periphery. It is also possible that the anterior parts of intraocular instruments will at
first appear somewhat thicker and slight bent or curved.
Keep endo-illumination as far as possible from the retina and increase illumination at its tip. This utilizes
the wide-angle effect of the Wide Field Lens to its fullest. Light intensity at the retina will be somewhat
reduced due to the distance from the retina.
Fluid/gas exchanges, fluid/silicone exchanges and gas/silicone exchanges can be easily be optically
monitored even in phakic eye with the Wide Field Lens.