Straight-eye amblyopia with monocular hyperopia. Age 4.
This 4-year-old presented without previous spectacle correction and had complaints of blurred vision in the right eye. At the time of the initial examination, acuities with correction were OD 20/100, OS 20/20, stereo acuity distance 360”. There was no evidence of strabismus. Because of the age of the child, and the condition itself, it was difficult to get accurate motor fusion limits. An iseikonic correction of 0% was prescribed using the SHAW lens software. The patient was instructed to wear the SHAW lenses full-time and patching was not employed. At the one-month follow-up visit, the acuity was OD 20/32, OS 20/20, stereo acuity 80”. At the 6-month follow-up, visual acuity was OD 20/20, OS 20/20, stereo acuity 40”.
This case illustrates how the wearing of spectacle correction in anisometropic amblyopia provides amelioration of refractive amblyopia without the need for patching. Further, as amblyopia decreased, the quality of binocular vision improved. Classic clinical thinking would suggest that spectacles have improved the quality of the image in the right eye, leading to the amelioration of the amblyopia. However, recent evidence points to a path where it is the restoration of the binocular vision that actually improves the amblyopia.
This patient’s parents ordered an additional pair of spectacles from an online optical supplier. The young patient put them on and then just took them off, saying, “I can’t wear those.” The refractive prescription was correct and the PD was supplied as requested. However, these traditional lenses failed to correct the static and dynamic components of the anisometropia, making the glasses unwearable.
Note the improvement in the zone of binocular vision comfort in addition to the elimination of static aniseikonia and the dramatic reduction of dynamic aniseikonia. Keep in mind that children are even less willing to try to “get used to it” than adults are.