For spherical prescriptions, or with corneal astigmatism less than 1.
Toroidal RGPs are useful when there is lenticular astigmatism present, or when there is a high degree of corneal astigmatism.
We note that the new product from Abbott Labs is superior to conventional IOLs since it has the ability to correct the loss of focus due to pre-existing corneal astigmatism
of one diopter or greater.
d The eye has predominantly lenticular astigmatism and little corneal astigmatism
This will typically occur when corneal astigmatism is greater than 2.
Final acuity should be good, due to the fact that the corneal astigmatism is neutralised by the tear lens.
In addition, most soft multifocal contact lenses do not correct corneal astigmatism
RGP lenses provide excellent visual qualities, particularly for regular or irregular corneal astigmatism, along with patients who possess high amounts of refractive error.
Keratometry will also reveal the amount of corneal astigmatism and any corneal distortion present.
c) The level of corneal astigmatism
depends on the extent of the causative condition
For spherical prescriptions or with corneal astigmatism
less than 1.
They are aimed at the correction of normal ametropia, corneal astigmatism
, presbyopia, keratoconus and ectasia, and post-surgical corneas such as post-graft and post-refractive surgery.