Corneal densitometry and its correlation with age, pachymetry, corneal curvature, and refraction

• Published in: International ophthalmology Vol. 37; no. 6; pp. 1263 - 1268
• Main Authors: Garzón, Nuria, Poyales, Francisco, Illarramendi, Igor, Mendicute, Javier, Jáñez, Óscar, Caro, Pedro, López, Alfredo, Argüeso, Francisco
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.12.2017; Springer Nature B.V
• Subjects: Adult; Age; Aging - physiology; Annuli; Cornea; Cornea - anatomy & histology; Corneal Pachymetry; Corneal Topography; Correlation coefficient; Correlation coefficients; Curvature; Densitometers; Densitometry; Densitometry - methods; Equivalence; Error analysis; Eye diseases; Female; Humans; Light scattering; Male; Mathematical analysis; Medicine; Medicine & Public Health; Middle Aged; Ophthalmology; Original Paper; Refraction, Ocular - physiology; Statistical analysis; Corneal transparency; Corneal densitometry; Cornea
• ISSN: 0165-5701; 1573-2630
• DOI: 10.1007/s10792-016-0397-y

Purpose To determine normative corneal densitometry values in relation to age, sex, refractive error, corneal thickness, and keratometry, measured using the Oculus Pentacam system. Methods Three hundred and thirty-eight healthy subjects (185 men; 153 women) with no corneal disease underwent an exhaustive ocular examination. Corneal densitometry was expressed in standardized grayscale units (GSU). Results The mean corneal densitometry over the total area was 16.46 ± 1.85 GSU. The Pearson correlation coefficient for total densitometry was r  = 0.542 ( p  < 0.001). Statistically significant differences were found between men and women for the total area ( p  = 0.006), with readings of 16.22 ± 1.54 GSU and 16.60 ± 1.83 GSU, respectively. When the cornea was divided into layers of different depths, a significant correlation was found for all layers and age: r  = 0.447 ( p  < 0.001), r  = 0.563 ( p  < 0.001), and r  = 0.520 ( p  < 0.001) for the anterior, central, and posterior layers, respectively. However, when the cornea was divided into concentric annuli starting from the center of the cornea, densitometry was strongly correlated only with age in the 6–10-mm annulus ( p  < 0.001). Neither mean keratometry nor spherical equivalent was correlated with corneal densitometry in any zone of the cornea ( p  > 0.05). Conclusions This is the first report of normative corneal densitometry values in relation to keratometry, corneal thickness, and spherical equivalent measured with the latest Oculus Pentacam software. Corneal densitometry increases with age, but corneal keratometry and refractive parameters do not affect light scattering in the human cornea.