CATARACT/ IOL

Nuclear cataract lens usually responsible for HOAs

Internal optics in eyes with nuclear cataracts caused higher-order aberrations (HOAs) more often than not, according to a study in the December issue of the Journal of Cataract & Refractive Surgery.

Myoung Joon Kim, M.D., University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea, and colleagues used a visual function analyzer that combines ray-tracing aberrometry and corneal topography to measure wavefront aberrations in 33 eyes of 20 patients who had nuclear cataracts.

Dr. Kim reported that the wavefront maps of the entire eye were similar to those of the internal optics. The average root mean square (RMS) of HOAs in the entire eye and in the internal optics was 1.59 microns and 2.13 microns, respectively, with an optical zone of 6.5 mm.

The predominant HOA in the entire eye and the internal optics was coma; the mean RMS of coma was 0.98 microns in the entire eye and 1.28 microns in the internal optics. The spherical aberration of the internal optics correlated negatively with the grade of nuclear cataract (r = −0.450, P=0.009).

So the researchers concluded that most HOAs in eyes with nuclear cataracts were due to the internal optics, with coma being the predominant HOA. Dr. Kim added that these findings may explain the subjective symptoms in patients with nuclear cataract.

Reported by: EyeWorld News Services