Gursoy Huseyin, Sahin Afsun, Basmak Hikmet, Ozer Ahmet, Yildirim Nilgun, Colak Ertugrul
Department of Ophthalmology, Eskişehir Osmangazi University Medical Faculty, Eskişehir, Turkey.
Optom Vis Sci. 2011 Aug;88(8):912-9. doi: 10.1097/OPX.0b013e31821cc4d6.
To compare the central corneal thickness (CCT), axial length (AL), anterior chamber depth (ACD), and lens thickness (LT) measured with Lenstar with those obtained with ultrasound pachymetry and A-scan contact ultrasound (ASU) in children.
ODs of 565 school children were included. All measurements were obtained 30 min after instilling 1% tropicamide. For each instrument, three consecutive measurements per each child were performed. Initially, examiner 1 performed measurements with Lenstar to obtain CCT, AL, ACD, and LT. Later, examiner 2 performed measurements with corneal pachymetry to obtain CCT. Finally, ASU was used by examiner 2 to obtain AL, ACD, and LT. Four parameters obtained with Lenstar were compared with those obtained with pachymetry and ASU using Pearson correlation coefficients (r) and Bland-Altman analyses.
Lenstar measurements were obtained in 557 of 565 subjects(mean age; 10.48 ± 2.11 years, mean spherical equivalent of the ODs; +0.47 ± 1.18 diopters) whereas ASU and pachymetry could be performed in 530 of 565. Four hundred seventy-nine subjects were statistically assessed after 41 subjects were extracted as outliers from 530 subjects in whom all instruments could be performed. Mean difference between pachymetry and Lenstar was 13.20 ± 13.13 μm [95% confidence interval (CI): 12.01 to 14.37]. Mean difference between ASU and Lenstar was -0.72 ± 0.35 mm (95% CI: -0.75 to -0.69) for AL, -0.27 ± 0.32 mm (95% CI: -0.30 to -0.24) for ACD, and 0.24 ± 0.28 mm (95% CI: 0.22 to 0.27) for LT. R values were 0.912 (p < 0.001), 0.904 (p < 0.001), 0.487 (p < 0.001), 0.369 (p < 0.001) for CCT, AL, ACD, and LT respectively.
AL and ACD were found to be greater with Lenstar, whereas CCT and LT measures were smaller. It is concluded that there was agreement between instruments for CCT and ACD, because the small differences between measures were clinically insignificant. AL and LT values cannot be used interchangeably. If these differences are considered, Lenstar can replace ASU and pachymetry for the majority of children.
比较使用Lenstar测量的儿童中央角膜厚度（CCT）、眼轴长度（AL）、前房深度（ACD）和晶状体厚度（LT）与使用超声测厚法和A超接触式超声（ASU）测量的结果。
纳入565名在校儿童的右眼。所有测量均在滴入1%托吡卡胺30分钟后进行。对于每种仪器，对每个儿童进行连续三次测量。最初，检查者1使用Lenstar进行测量以获得CCT、AL、ACD和LT。随后，检查者2使用角膜测厚仪进行测量以获得CCT。最后，检查者2使用ASU获得AL、ACD和LT。使用Pearson相关系数（r）和Bland-Altman分析将Lenstar获得的四个参数与测厚法和ASU获得的参数进行比较。
565名受试者中的557名（平均年龄；10.48±2.11岁，右眼平均等效球镜度数；+0.47±1.18屈光度）获得了Lenstar测量值，而565名中的530名可以进行ASU和测厚法测量。在从530名可以使用所有仪器的受试者中提取41名作为异常值后，对479名受试者进行了统计学评估。测厚法与Lenstar之间的平均差异为13.20±13.13μm[95%置信区间（CI）：12.01至14.37]。ASU与Lenstar之间的平均差异为：AL为-0.72±0.35mm（95%CI：-0.75至-0.69），ACD为-0.27±0.32mm（95%CI：-0.30至-0.24），LT为0.24±0.28mm（95%CI：0.22至0.27）。CCT、AL、ACD和LT的r值分别为0.912（p<0.001）、0.904（p<0.001）、0.487（p<0.001）、0.369（p<0.001）。
发现Lenstar测量的AL和ACD更大，而CCT和LT测量值更小。得出结论，CCT和ACD的测量仪器之间存在一致性，因为测量之间的小差异在临床上无显著意义。AL和LT值不能互换使用。如果考虑这些差异，Lenstar可以替代ASU和测厚法用于大多数儿童。
