This patient was referred from the pediatrics department for a contact lens fitting. Pediatrics’ goals were to maximize her vision so she will be more successful with vision therapy for an intermittent left exotropia.
OD: -1.75-6.50 x 005; 20/30; Manual Ks 41.75/46.75
OS: -1.00-8.50 x 180; 20/50; Manual Ks 40.75/47.75
Initially she was fit with bitoric corneal GPs which provided excellent vision; however, she struggled with redness and irritation.
Initial bitoric corneal GPs:
OD: -2.00/-6.00; 41.50/45.75; 8.8 mm; 20/25
OS: -2.00/-6.00; 41.50/46.75; 8.8 mm; 20/40
Figure 12. Prominent impression of the lens and punctate stain upon removal of bitoric GP.
Unfortunately, upon follow-up, the lenses became adherent (See Figure 12). Therefore, she was refit into scleral lenses. Her staining resolved, and she was able to wear the sclerals throughout the school day.
Final scleral GPs:
OD: -5.50; 7.40 mm; 14.3 mm flat edge; 20/25
OS: -4.50; 7.40 mm; 14.3 mm flat edge; 20/25
After vision therapy and a year in the sclerals, best corrected vision improved to 20/20 and 20/25, and her left eye no longer tropes.
The patient presents to the clinic with a desire to improve his vision in his left eye. He is currently wearing spectacles:
OD: -0.50-2.50 x 180; 20/20
OS: +2.00-4.00 x 180; 20/200
OD: -1.50-2.50 x 180; 20/20; SimKs 40.00/43.10
OS: -1.75-6.50 x 175; 20/30; SimKs 40.70/45.30
Cycloplegic evaluation revealed a left prescription of +6.00-7.50 x 170. However, with the full prescription, the patient experienced diplopia at near and OS suppression at distance. Therefore, he was fit with bitoric lenses in hopes of improving his vision, equalizing image size and eliminating diplopia (see Figures 13 and 14).
Figures 13 (top) and 14 (bottom). High regular astigmatism visible on topography with corneal thinning but no posterior ectasia.
An initial pair of diagnostic lenses were applied based upon Mandell-Moore, and after over-refraction the following corneal GPs were ordered:
OD: -0.75/-2.25; 41.00/43.00; 9.2 mm; 20/20
OS: +5.50 back toric; 39.50/44.75; 9.2 mm; 20/25
The diplopia resolved with the new lenses, and the patient reported increased driving confidence, especially at night.
All of these patients experienced vision improvement when they were fit with contact lenses to correct their astigmatism. Based on the patient’s needs, each needed a different type of lens.
For myopia control, toric ortho-k was helpful for Case 1. For his active lifestyle, soft torics provided a better option for Case 2. For Case 3, a scleral was needed to provide appropriate ocular health and vision correction. And for Cases 4 and 5, GP torics optimized vision.
We can easily dispell the myth, “I can’t wear contact lenses because I have astigmatism.” Today’s lenses offer high quality visual options with excellent comfort and efficient empirical fitting.
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