Page 45 - The Book Pi in eye

Pi in eye

macula can be studied and documented in detail. It is adept at picking
up details not seen with the naked eye.

Figure 5.8 OCT of the anterior chamber

Calculating the Power of the Synthetic Intraocular Lens
Implant:
Patients that are planning on having lens exchange surgery should
be aware of the importance of examining the power of the cornea and
the length of the eye. The key goal of Prelex is to get great vision
using an ideal lens which focuses images at all distances on the retina.
Basic to this concept is getting the optimum power of the lens for that
eye.
The shape of the cornea, the length of the eye and the final position of the lens
inside the eye dictate the best power of the lens. The more accurate these three
variables are, the better the prediction. The cornea shape is measured
by manual keratometry or automated corneal topography.
Either immersion ultrasound or laser can calculate the length of
the eye. In the ultrasound method, sound waves are used; after a lens
filled with a liquid is placed on the eye. The laser is a non contact
method employing light to calculate the distance. The ultrasound
measures the anatomical and lasers, the visual axis length. In majority
of cases both are similar. Ultrasound is beneficial in cataracts that do
not allow laser light to pass through.
It is highly recommended that any use of the contact lenses be
terminated. For best results, soft contact lenses should be removed 3-
7 days before exam and hard contact lens or gas permeable contacts
(RGP), 3-4 weeks prior.
Effective lens position (ELP) is the exact place that the synthetic
lens is expected to reside. This can vary on surgical techniques and it

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