Intrasession repeatability of optical coherence tomography measures in active neovascular age‐related macular degeneration

Objectives: To determine the repeatability of Stratus optical coherence tomography fast macular thickness map analysis in patients with active neovascular age‐related macular degeneration (nAMD). Methods: Consecutive pairs of scans from 112 eyes of 112 consecutive patients with active nAMD were analyzed. The Bland–Altman coefficient of repeatability (CR) was calculated for each retinal thickness or volume measure. Results: The CR for the central 1 mm macular subfield was 59 μm (18% of retinal thickness) and did not exceed 69 μm in any subfield. There was much poorer repeatability for the center‐point thickness (CPT) measure (CR of 78 μm; 24%). However, in the subgroup of 38 patients with no Stratus software low analysis confidence message on either analysis map, the revised CR (42 μm) for the CPT measure and the A1 subfield (40 μm) were similar. Conclusion: Optical coherence tomography‐derived retinal thickness measurements are subject to measurement variability in patients with active nAMD. The results suggest a change criterion of more than 59 μm in central 1 mm (A1) subfield macular thickness is necessary to distinguish true clinical change from measurement variability in these patients.     

噪声视力表在儿童视力检查中的可重复性分析

目的探讨噪声视力表对儿童视力检查的可重复性及其相关影响因素。方法在门诊首诊患儿中,随机选择无理解障碍及除屈光不正外无其他器质性眼病儿童200例,使用噪声视力表进行噪声视力重复检查。采用配对t检验进行统计学分析。结果两次视力测量之间差异的均数为O.03行,（P=0.515）;两次视力测量结果按性别分组无明显差异（P=1.0,P=0.262）;按年龄分组亦无明显差异（P=0.159,P=0.786）;按屈光不正分组,其中近视组两次视力测量结果有明显差异（P=0.010）。近视儿童视力检查一致性较差,而正视及远视儿童的视力检查一致性较好（P=0.133,P=0.083）。结论结果提示噪声视力表适合儿童视力检查,建议推广使用。     

Crystaleye电脑比色仪测色可重复性研究

目的 考察Crystaleye电脑比色仪测色的可重复性。方法 由4位医生用Crystaleye电脑比色仪测定Vita95比色板的色卡3次。通过计算机读取颜色参数并分析3次测色结果的差异,比较3次测得的L、a、b值和色差ΔE×ab=(ΔL×2+Δa×2+Δb×2)1/2。结果 每位医生3次测得的L、a、b值各自组内比较结果均无统计学差异(P>0.05),各医生间的测量结果存在统计学差异(P<0.05)。3次测色的平均色差ΔE×ab在1 nbs左右,颈部最大色差为2.5 nbs,最小色差为0.15 nbs,体部最大色差为2.16 nbs,最小色差为0.11 nbs,切端最大色差为2.12 nbs,最小色差为0.15 nbs。结论 Crystaleye分光光度比色仪的测色结果具有一定可重复性。?     

Repeatability of Ophtha Top topography and comparison with IOL-Master and LenstarLS900 in cataract patients

AIM: To determine the repeatability of Ophtha Top topography and assess the consistency with intraocular lens (IOL)-Master and LenstarLS900 (Lenstar) in measuring corneal parameters among cataract patients. METHODS: Totally 125 eyes were enrolled. Corneas were successively measured with Ophtha Top, IOL-Master and Lenstar at least three times. The flattest meridian power (Kf), the steepest meridian power (Ks), mean power (Km), J0 and J45 were recorded. Intra-class correlation coefficients (ICCs), the coefficient of variance (COV), within subject standard deviation (Sw), and test-retest repeatability (2.77Sw) were adopted to determine the repeatability. The 95% limit of agreement (95%LOA) and Bland-Altman plots were used to assess comparability. RESULTS: Repeatability of Ophtha Top topography for measuring corneal parameters showed the ICCs were all above 0.93, 2.77Sw was lower than 0.31, and the COV of the Kf and Ks was lower than 0.25. The keratometric readings with Ophtha Top topography were flatter than with the IOL-Master and Lenstar devices, while the Pearson correlation coefficients were over 0.97. The J0 and J45 with Ophtha Top topography were smaller compared with Lenstar and IOL-Master, while was comparable between Lenstar and IOL-Master. CONCLUSION: Ophtha Top topography shows excellent repeatability for measuring corneal parameters. However, differences between the Ophtha TOP topography and Lenstar, IOL-Master both in cornea curvature and the astigmatism should be noted clinically.     

两种光学生物测量仪在中国青少年人群中应用的比较

目的 评估两种光学生物测量仪(Lenstar LS900(R)与SW-9000)对青少年眼球生物测量结果的重复性,并比较两种仪器测量值的一致性.方法 采用前瞻性研究,纳入65例屈光不正患者,分别用SW-9000与Lenstar LS900(R)进行右眼眼球生物测量,应用单因素方差分析评估仪器的可重复性,应用Bland-Altman散点图对两种仪器测量值进行一致性评价.结果 Lenstar LS900(R)测量指标AL、K1、K2、CCT、AD、LT、PD的重复性良好,ICC均大于0.90;WTW略差,但仍大于0.88.SW-9000测量指标AL、K1、K2、CCT的重复性良好,ICC均大于0.9,其余参数重复性较差.将两种仪器重复性均良好的AL、K1、K2、CCT分别进行比较,发现SW-9000所测AL、CCT比Lenstar LS900(R)略长,且差异均有统计学意义(均为P＜0.05);而K1、K2均无明显差异(均为P ＞0.05).此外两种仪器间AL、K1、K2、CCT均存在密切的线性相关(均为r＞0.97,均为P＜0.01).Bland-Altman散点图显示,两种仪器测量指标的95％ LoA分别为AL:-0.057～0.133 mm;K1:-0.456～0.369 D;K2:-0.388～0.549 D;CCT:-3.483～8.016 μm.结论 对于8～18岁青少年人群,Lenstar LS900(R)与SW-9000眼球生物测量指标(包括AL、K1、K2、CCT)均具有良好的重复性,SW-9000与Lenstar LS900(R)测量参数AL、K1、K2、CCT相关性高,且4个参数95％ LoA在临床上可接受,一致性良好.