Abstract
Purpose: :
To assess the average lens density (ALD) covering 360 degrees and the nuclear lens density (NLD) using the Scheimpflug densitometry and to determine their correlation with best-corrected visual acuity, and lens grading based on the Emery and Little classification.
Methods: :
Fifty three eyes (40 cataract and 13 clear lenses) from 53 subjects (mean 57.3 ± 22.0 years) were included in the study. 360 degrees lens density measurements were performed with Pentacam device (Oculus, Germany), which is comprised of a rotating Scheimpflug camera and short-wavelength slit light. Following lens densitometry metrics were evaluated: NLD at which lens densitometry is greatest on a horizontal cross-section; 3-dimensional (3D), in which a fixed, circular 1.0 mm (NLD 1.0 mm) and 3.0 mm (NLD 3.0 mm) areas of the lens are selected and a mean lens densitometry value given.
Results: :
The densities of the lens in all metrics were increasing with higher grades. The NLD in the Emery Grade 0, 1, 2 and 3 were 7.3 ± 2.0, 12.7 ± 1.7, 16.6 ± 5.7, and 22.8 ± 8.1, respectively. The ALD 1.0 mm in the Emery Grade 0, 1, 2 and 3 were 9.4 ± 1.3, 13.3 ± 1.8, 15.4 ± 2.7, and 17.5 ± 2.5, respectively. The ALD 3.0 mm in the Emery Grade 0, 1, 2 and 3 were 9.1 ± 1.2, 12.3 ± 1.5, 14.0 ± 2.2, and 15.7 ± 1.6, respectively. Also, best-corrected visual acuity significantly correlated with NLD (r = 0.635; p < 0.001), ALD 1.0 mm (r = 0.712; p < 0.001) and ALD 3.0 mm (r = 0.742; p < 0.001). .
Conclusions: :
The 3-D lens densitometry using Pentacam device could be helpful for follow-up of cataracts, and could be a potential tool for prediction of visual acuity in cataract patients, although further studies are needed to clarify the effects of cataracts on visual performance.
Keywords: aging: visual performance • cataract • imaging/image analysis: clinical