Al-Farhan Haya M, Almutairi Reem N
King Saud University, College of Applied Medical Sciences, Department of Optometry and Vision Sciences, Riyadh, Kingdom of Saudi Arabia.
Clin Ophthalmol. 2013;7:141-7. doi: 10.2147/OPTH.S39463. Epub 2013 Jan 16.
To compare the precision of anterior chamber angle (ACA) and anterior chamber depth (ACD) measurements taken with ultrasound biomicroscopy (UBM) and the Artemis-2 Very High Frequency Ultrasound Scanner (VHFUS) in normal subjects.
Prospective study.
We randomly selected one eye from each of 59 normal subjects in this study. Two subjects dropped out of the study; the associated data were excluded from analysis. ACA and ACD measurements were obtained using the VHFUS and the UBM. The results were compared statistically using repeated-measures analysis of variance for the intraobserver repeatability, unpaired t-test, and limits of agreement.
The average ACA values for the UBM and the VHFUS (±standard deviation) were 41.83° ± 5.03° and 33.36° ± 6.03°, respectively. The average ACD values were 2.96 ± 0.34 mm and 2.87 ± 0.31 mm. The intraobserver repeatability analysis of variance P-values for ACA and ACD measurements using UBM were 0.10 and 0.68, respectively; for the Artemis-2 VHFUS, the respective values were 0.68 and 0.09. The difference in ACA measurements was statistically significant (t = 8.41; P < 0.0001), while the difference in ACD values was not (t = 1.51; P < 0.13). The mean ACA difference was 8.50° ± 2.50°, and the limits of agreement were +13.30° to -3.60°. The mean ACD difference was 0.09 ± 0.27 mm, and the limits of agreement ranged from 0.61 mm to -0.43 mm. The mean difference percentage of ACD was 3.1% for both instruments.
In case of the ACD, both instruments can be used interchangeably; however, with the ACA instruments, they cannot be used interchangeably.
比较超声生物显微镜（UBM）和Artemis - 2甚高频超声扫描仪（VHFUS）在正常受试者中测量前房角（ACA）和前房深度（ACD）的精度。
前瞻性研究。
本研究中我们从59名正常受试者中随机选取一只眼睛。两名受试者退出研究；相关数据被排除在分析之外。使用VHFUS和UBM获得ACA和ACD测量值。使用重复测量方差分析进行观察者内重复性、非配对t检验和一致性界限分析，对结果进行统计学比较。
UBM和VHFUS的平均ACA值（±标准差）分别为41.83°±5.03°和33.36°±6.03°。平均ACD值分别为2.96±0.34mm和2.87±0.31mm。使用UBM测量ACA和ACD的观察者内重复性方差分析P值分别为0.10和0.68；对于Artemis - 2 VHFUS，相应的值分别为0.68和0.09。ACA测量值的差异具有统计学意义（t = 8.41；P < 0.0001），而ACD值的差异无统计学意义（t = 1.51；P < 0.13）。平均ACA差异为8.50°±2.50°，一致性界限为+13.30°至 - 3.60°。平均ACD差异为0.09±0.27mm，一致性界限范围为0.61mm至 - 0.43mm。两种仪器的ACD平均差异百分比均为3.1%。
对于ACD，两种仪器可互换使用；然而，对于ACA测量仪器，它们不能互换使用。
