Analysis of corneal astigmatism with NIDEK axial length scan in caucasian cataract surgery candidates
Aims and Objectives: The aim of the study was to analyze and quantify the pattern of corneal astigmatism in Caucasian cataract surgery patients using a new optical biometer (axial length [AL] Scan, NIDEK Co., Gamagori, Japan).
Patients and Methods: The datasets of cataract surgery patients acquired between March 1, 2014, and April 15, 2016, were collected and analyzed. The corneal power (flat keratometry, steep keratometry, and mean keratometry), negative cylinder power, and axis of astigmatism were recorded. Keratometry values were optically measured by optical low coherence interferometry (AL‑Scan, NIDEK Co., Ltd.,) before cataract extraction.
Results: The study comprised 1233 eyes of 838 consecutive cataract candidates with a mean age of 66.8 ± 10.7 years (range 40–97 years). The mean keratometry value and corneal astigmatism were 43.69 ± 1.61 D and 0.84 ± 0.70 D, respectively. Corneal astigmatism of 1.00 D or greater was found in 344 eyes (27.9%), and 548 eyes (44.4%) had against‑the‑rule astigmatism. A trend toward decreasing J0 and J45 with age was found by linear regression models. The per‑year increase in age was associated with a J0 and J45 decrease of 0.002 D and 0.001D, respectively.
Conclusion: This study provides the distribution of astigmatism axis and power for cataract patients in age subsets from Turkey.
Keywords: Astigmatism, Cornea, NIDEK axial length‑scan, optical biometer