11/19/2025
We were kindly referred a patient with high myopia (about -9.00 in each eye) for a contact lens fitting to help improve her vision and stability.
Per the patient, she had successfully worn corneal gas permeable lenses for 40 years, however, over the past few years, she has had more and more issues with the lens stabilizing on her eyes. Based on her topographies, she does have regular astigmatism.
The left eye has more than 2.00 D of corneal astigmatism, so a bitoric corneal gas permeable lens should be considered.
Her main complaints are vision instability and also discomfort with excessive lens movement. Her scleral topography in both eyes showed excessive scleral toricity at over 300um. The diagnostic scleral lenses only went up to 300um, so we had to use the highest ones in the fitting set.
We tried a scleral lens on both eyes today, to see if she liked the comfort and vision.
The right Diagnostic lens had 300um of scleral toricity and the left lens only had 200um of scleral toricity. You can see that the lens moves a lot more in the left eye, therefore, we should order her lens with increase toricity.
She is able to achieve 20/15 vision in each eye with an over-refraction, and she was very happy with the comfort and stability of the lenses.
She was also taking about -1.25 D of cylinder in the left eye, likely due to internal astigmatism from the crystalline lens. We will add an F1 toric to the left lens to account for this. Although the patient would probably do well with a corneal gas permeable lens for each eye, I think the comfort and vision will be excellent in custom scleral lenses. Also, the left eye fit and prescription in a corneal gas permeable lens will be a bit challenging to perfect, and if the lens rotates at all, she will experience blurry vision.
I decided to avoid these potential issues and move on to a scleral design.
