Objective Optical Function Evaluation in a Child with Crystalline Lens Dislocation Using a Point Spread Function Analysis System

Abstract

Abstract: : Purpose: To objectively estimate the optical function in a child with crystalline lens dislocation using a new point spread function (PSF) analyzer. Methods: Bilateral visual function in a 6–year–old boy with lens dislocation associated with Marfan’s syndrome was evaluated by PSF analysis. Double–pass PSFs were obtained and the optical status was objectively analyzed. The retinal images were simulated and evaluated objectively by convoluting the PSFs to Landolt’s ring images. Results: The subjective best–corrected visual acuities (BCVAs) were 30/20 (20/15 × sph. –2.00 D, cyl. –2.50 D, ax. 160°) in the right eye and 20/50 (20/30 × sph. –2.75 D, cyl. –5.00 D, ax. 55°) in the left eye. Autorefractometry showed 3.75 D of astigmatism in the right eye; the left eye was unmeasurable. Using PSF analysis, the anterior and posterior focal lines in the left eye were identified objectively and the estimated astigmatism was calculated as 9.0 D. Simulated retinal images of Landolt’s rings were synthesized, and it was theorized that astigmatic correction should substantially improve optical function. After prescribing glasses based on PSF analysis data, the BCVA improved to 20/22. In the right eye, although the presumed amount of astigmatism was less than in the left eye, asymmetrical components of aberration were recognized in the aerial images and simulated retinal images that seemed uncorrectable with spectacles. Conclusions: In eyes with lens dislocation, marked oblique astigmatism occurred according to the degree of the dislocation. The PSF analysis system can objectively evaluate the characteristics of the optical function in pediatric eyes in which subjective examinations are difficult to perform.

Keywords: infant vision • astigmatism • clinical (human) or epidemiologic studies: systems/equipment/techniques