Scleral lenses

 One of the most recent breakthroughs in contactology has been the introduction of a new generation of scleral lenses: the Misa® lenses by Microlens. This innovative scleral lens system pushed the boundaries in correcting pathological corneas.

·         The application of the Misa® lenses can prevent or postpone surgery.

·         The application of the Misa® lenses can restore the optical system of the eye.

·         The Misa® lenses do not touch the vulnerable cornea and fully respect the integrity of the cornea.

·         The Misa® lenses are very comfortable to wear.

·         The procedure of fitting the scleral lenses is easy and predictable.

Misa® lenses are available in two design types:

·         The full scleral Misa® lens


The unique principle of the Misa® lenses


The Misa® scleral lens rest on the sclera outside of the limbal area. The cornea should be free of touch by vaulting over it. Furthermore, the tear reservoir between the cornea and the contact lens should not be too big: about 0.25 mm. (approximately half the cornea thickness)


In scleral lenses the height of the lens is much more important than the choice of radius. This height is called the sagittal height or the vault height. In Misa® lenses vault height is used.

The vault height is the height difference between the inside top of the lens and the point where the lens lands on the sclera and turns into the scleral zone which is resting on the sclera.

The vault height of a spherical segment is determined by the radius and the diameter of that spherical segment. When the radius of the spherical segment changes, the vault height will also change. In existing scleral lens systems the vault height of the scleral lens is determined by the composition of spherical curves: a steeper radius creates a larger vault height than a flatter radius on the same segment. When a change in radius is necessary to improve the fitting, the vault height is changing as well.


Because of the complex relation between the different curves in existing scleral systems the practitioner has to be very experienced to choose the right composition of curves that:

·         Ensures the exact height

·         Provide the preferred shape which corresponds with the shape of the eye

As a result of this fitting complexity, scleral lenses never became widely used.The innovative Misa® scleral lens system completely changed the fitting procedure:

The fitting procedure is simplified and became predictable and transparent and it is possible to work with smaller lens diameters.

The Misa lens is constructed in a way that when the vault height is determined the scleral aperture diameter, radius and overall lens diameter can be altered independent without affecting the vault height.When changing one of the parameters, the resulting differences in vault height will immediately be compensated by the: Elongation curve.

When changes in the lens theoretically would make the vault height higher or lower, the elongation curve will compensate this in a way that the vault height remains the same.The first step in fitting a Misa® lens is to find the optimal vault height with the trial set. After this, the practitioner is free to choose any radius or landing zone.

Until now the fitting of scleral lenses has been reserved for only a few practitioners with years of experience in order to have a reasonable or good percentage of success.With the introduction of the Misa® scleral lens system the threshold for the application as well as the fitting ofthe lenses has been lowered tremendously. That is the reason why in the meantime thousands of patients are successfully equipped with these lenses, and now enjoy a big improvement in their quality of live.








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