No abstract

Background This study aimed to evaluate consecutive measurements of biometric parameters, age, and refraction in a cohort of Turkish primary school-age children and to assess the correlation between biometric changes and refraction. Methodology The study population was seven and 12-year-old children (n = 197). The retrieved data consisted of three consecutive measurements with a one-year interval for each subject. Data from one eye (right) were used. Age, gender, body mass index, spherical equivalent (SE), axial length (AL), anterior chamber depth (ACD), central corneal thickness (CCT), keratometry (K), and lens thickness (LT) were analyzed. The onset and final data were retrieved from the database in 2013 and 2016, respectively. Statistically, logistic and Cox regression models of all parameters were analyzed, and the significance level was set at 5%. Results The median of the onset and final SE values were -0.00 D (0.00-0.00) and 0.50 D (0.19-1.00), respectively. The onset AL (hazard ratio (HR) = 5.82, 95% confidence interval (CI) = 3.45-9.76, β = 1.76, p < 0.001), K mean (HR = 2.28, 95% CI = 1.67-3.11, β = 0.82, p < 0.001), and age (HR = 0.77, 95% CI = 0.59-0.99, β = -0.26, p = 0.046) were correlated with myopia progression. To calculate the estimated SE, the onset data were included in the logistic regression model. The onset SE (β = 0.916, p < 0.001), AL (β = -0.451, p < 0.001), ACD (β = 0.430, p = 0.005), and K (β = -0.172, p < 0.001) were correlated with the mean final SE. An equation was generated using the regression model analysis. Conclusions The onset parameters of SE, AL, ACD, and K were confirmed to correlate with the final SE values in the proposed model. To confirm the use of the refractive calculator, a cross-validation analysis is needed to estimate three-year subsequent refractive error among seven and 12-year-old children.

Bu çalışmanın amacı TRK-2P cihazı (Topcon Medical Systems Inc., Oakland NJ) ile elde edilen keratometri ve kornea kalınlık değerlerini, Pentacam-HR cihazı (Oculus; Optikgeräte GmbH, Wetzlar, Almanya) ile elde edilen ön kornea keratometrisi ve pakimetri değerleri ile karşılaştırmaktır. Veri tabanlarımızda her iki cihazın tam kayıtlarına sahip olan hastalar bu gözlemsel çalışmaya dahil edildi. On iki hastanın keratokonus tanılı yirmi üç gözü ve herhangi bir göz sorunu olmayan on altı hastanın otuz iki gözü çalışmaya dahil edildi (kontrol). Keratometri ve santral kornea kalınlığı (SKK) çıktıları TRK-2P ve Pentacam-HR ile elde edilmiştir. Ortalama ön kornea keratometrisi ve pakimetri verilerinin tutarlılığı, sınıf içi korelasyon katsayısı (ICC) kullanılarak ilişkilendirildi. Ortalamalar paired t-testi kullanılarak istatistiksel olarak analiz edildi (α=0.05). Ortalama keratometri TRK-2P ve Pentacam-HR kontrollerde 42.64 D±2.02 ve 42.79 D±1.95 iken keratokonusta 47.64 D±5.24 ve 47.16 D±4.65 idi. Keratometri verilerindeki ortalama farklılıklar kontroller için 0.14 D ve keratokonus için 0.48 D idi (p&lt;0.001). TRK-2P ve Pentacam-HR ortalama SKK değerleri sırasıyla kontrollerde 560,27±42,18 µm ve 537,63±36 µm iken keratokonus hastaları için sırasıyla 489,67±45,13 µm ve 470,22±38,14 µm idi. SKK verilerindeki ortalama farklar kontroller için 22.63 µm ve keratokonus için 19.44 µm idi (p&lt;0.001). Kontrol ve keratokonus grupları için iki cihaz arasındaki ICC değerleri sırasıyla keratometri için 0,987 ve 0,983, SKK için 0,998 ve 0.994 idi (p&lt;0.001). Çalışmamızın sonuçları, TRK-2P, normal ve patolojik kornealarda tutarlı sonuç çıktıları üretir. Ayrıca, TRK-2P, yüksek güvenilirliğe sahip referans bir cihazla ilişkilendirildiğinde güvenilir bir araçtır. Ancak keratokonus progresyonunun izlenmesi açısından bu enstrümanlar birbirinin yerine geçebilecek alternatifler olamaz.

Aim To evaluate consecutive measurements of the biometric parameters, age, and refraction error in a Turkish population at primary school age. Materials and Methods A total of 197 children aged between 7-12 years were included. The data of three consecutive measurements of children, who were examined at least once a year for three years using both cycloplegic auto-refractometry and optical biometry, were used in this retrospective study. Spherical equivalent <-0.50D was considered to be myopic; >+0.75D was considered to be hypermetropic. Age, gender, body mass index, spherical equivalent, axial length, anterior chamber depth, central corneal thickness, keratometry, and lens thickness were analyzed. The onset data obtained in 2013 whereas, the final data were from 2015. Logistic and Cox regression analyses were performed (p<0.05). Results The mean of the onset and the final spherical equivalents were 0.19D (0.56), and 0.08D (0.80), respectively. The myopia prevalence was increased among refractive errors in observation periods (univariable analysis p=0.029; multivariable analysis p=0.017). The onset axial length (HR:4.55, 95%CI:2.87-7.24, p<0.001), keratometry (HR:2.04, 95%CI:1.55-2.67, p<0.001) and age (HR:0.73, 95%CI: 0.57-0.92, p=0.009) correlated myopia progression. To calculate the estimated spherical equivalent, the onset data were included in the logistic regression model. The onset data of spherical equivalent (β=0.916, p<0.001), axial length (β=-0.451, p<0.001), anterior chamber depth (β=0.430, p=0.005) and keratometry (β=-0.172, p<0.001) were found to be significantly associated with the mean SE at the final data. Conclusions To calculate the estimated spherical equivalent following three years, an equation was proposed. The estimated refractive error of children can be calculated by using the proposed equation with the associated onset optical parameters.