Fresnel prism use among orthoptists

Abstract

Purpose: To better understand current uses of Fresnel prisms.

Methods: A seventeen-question survey was completed by members of the American Association of Certified Orthoptists (AACO).

Results: Surveys were emailed to 211 orthoptists with a 36% response rate (n = 76). Prisms are used preoperatively to determine the surgical angle for 72% of respondents, 94% use prisms for postoperative misalignment. Prisms are used for incomitant deviations by up to 96% of respondents. The greatest patient objection to Fresnel use is reduced vision and distortion, not diplopia out of primary position. Of orthoptists surveyed, 99% use Fresnel prisms for near-distance disparity, 36% splitting prisms for upper and lower segments, and 40% encourage separate spectacles for near and distance. When deciding to grind prism, 66% wait more than one month. Ninety-nine percent of orthoptists use Fresnel prisms with adults, 67% use them with children. When correcting vertical and horizontal deviations, 70% of orthoptists rotate a prism over one lens.

Conclusion: Fresnel prisms have a wide use among North American certified orthoptists, including use with pediatric patients. Incomitance is not a contraindication to Fresnel use. Orthoptists prefer rotating one prism to bilateral Fresnel prisms.

Keywords: Fresnel prism; diplopia; orthoptist; strabismus.