We can discover whether the amblyopia presented by the patient is something that can be corrected with our technology within 12 – 20 weeks. This lens design methodology is indicated to correct straight-eye, refractive amblyopia without the use of patching often within a year, but the indication of whether this treatment will be effective can be discovered at about the 12 week mark after beginning wearing of the SHAW lens.
Refractive or straight eye lazy eye has been traditionally treated by suppressing the vision in one eye (the “good” eye) using either a patch or drops. Frankly, this is just cruel.
Amblyopia is caused by an image in one eye that is not synching with the image in the other eye. With a typical case of anisometropia, the image is focused in one eye and the other eye is defocused, and the brain will tend to ignore the defocused eye.
If the defocused eye requires a prescription different from the other eye’s – which it frequently does – then the image in the “lazy” eye might be larger than the image in the “non-lazy” eye. Now the brain can’t fuse the two images because they are different sizes.
So even though you give the child eye glasses, the treatment is not sufficient because the larger image from the treated eye no longer fuses with the image in the good eye, so suppression starts to occur. This inhibits the improvement we look for in the treatment of amblyopia.
By giving the child SHAW™ lenses, the images are equalized at the retinal level. Sensory fusion can now occur. The patient can integrate the two images more easily. We’ve found through clinical research that the time taken to correct the amblyopia is significantly reduced and, best of all, vision suppression using a patch or drops may not be necessary.
The optometrist refracts the patient as per usual and takes the frame and position of wear measurements.
The OD can either send this information to Shaw Lens or can input the information in the SHAW lens design tool. (In the SHAW lens tool, choose the Amblyopic design method. This will design a SHAW lens to a target value of 0% difference in the horizontal meridian.) Complete order using the SHAW lens design tool.
Assess after 12 weeks of full time wear.
If Best Corrected Visual Acuity has improved, continue full time wear. Assess at 6 months.
If BCVA has not improved, then atropine patch once a week for 6 weeks. If no improvement after that, then this case may not respond to this type of treatment. Other vision therapy can be done concurrently as the doctor recommends.
Please note that a SHAW lens system to address amblyopia is a complicated medical device. The lenses will likely be a different thickness left eye to right eye and one of the lenses could be thick. It’s always best to choose a plastic frame for these patients. Please don’t be surprised that the weaker eye has the thicker lens. That is the way we manage the static aniseikonia.
A new case report was published in Optometry & Vision Development, the official publication of the College of Optometrists in Vision Development, showing how the SHAW lens can be used to treat Amblyopia without patching. CLICK HERE to read the press release and full article.
For additonal case studies of the SHAW lens in the treatment of Amblyopia, CLICK HERE
