Repeatability And Reproducibility Of A Swept-source Optical Coherence Tomography Biometer OA-2000 And Detection Rate Studies

Objective:To evaluate the repeatability and reproducibility of swept-source optical coherence tomography biometrics(Tomey OA-2000)for measuring the biological parameters of the eyeball in healthy people and to compare the results of calculating the diopter of IOL with 8 different formulas.Eye biological parameters include axial length(AL),corneal curvature(K),anterior chamber depth(ACD),lens thickness(LT),central corneal thickness(CCT),pupil diameter(CCT),white to white(WTW).IOL diopter calculation formula includes Barrett Universal ?,Haigis standard,Haigis optimized,Hoffer Q,Holladay 1,SRK/T,SRK SHOWA,SRK ?.Methods:A diagnostic test was carried out in 103 healthy eyes.A total of 103 healthy young volunteers who underwent OA-2000 examination in the Department of Ophthalmology of the affiliated Hospital of North Sichuan Medical College from July to September 2018 were evaluated for repeatability and reproducibility.The right eyes were examined.Two examiners used OA-2000 for 3 consecutive measurements.One week later,the first examiner used OA-2000 for 3 consecutive measurements.The measurement of ocular biological parameters including axial length(AL),anterior chamber depth(ACD),corneal curvature(K),lens thickness(LT),central corneal thickness(CCT),pupil diameter(PD),and white to white(WTW).The evaluation of repeatability and reproducibility of each parameter based on within-subject standard deviation(Sw),repeatability limit of standard deviation(2.77Sw),coefficient of variation(Co V),and intra-class correlation coefficient(ICC).The biological parameters measured by the first examiner for 3 times were averaged and substituted into 8 formulas for calculating the diopter of intraocular lenses to calculate the degrees and make a pairwise comparison.Results:Of the ocular biological parameters measured by OA-2000,CoV was less than 2%while ICC was greater than 0.950,except PD and WTW.The repeatability and reproducibility of K,AL and ACD were all good.For K1((?)=2.5 mm and 3.0 mm),the Sw,was less than 0.120 D,the 2.77 Sw less than 0.350 D,the CoV less than 0.293%,and the ICC greater than 0.990;for K2((?)=2.5 mm and 3.0 mm),the Sw was less than 0.175 D,2.77Sw less than 0.485 D,CoV less than 0.396%,and ICC greater than 0.980;for Km((?)=2.5 mm and 3.0 mm),the Sw was less than 0.099 D,2.77 Sw less than 0.275 D,CoV less than 0.227%,and ICC greater than 0.996;the Sw of ACD was less than 0.024 mm,2.77Sw less than 0.066 mm,CoV less than 0.668%,and ICC greater than 0.993;the Sw,of AL was less than 0.014 mm,the 2.77 Sw less than 0.038 mm,the CoV less than 0.057%,and all of the ICCs were 1.000.In a pairwise comparison of the results of the calculation of the refractive power of eight artificial lenses,the Barrett Universal II-Holladayl group(P=0.543,the absolute value of intraocular lens diopter difference?=0.015D);the Barrett universal II-SRK/T group(P=0.126,?=0.083D);the Holaday 1-SRK/T group(P=0.158,?=0.068D);the Haigis optimized-SRK SHOWA group(P=0.082,?=0.019D).There was no significant difference in IOL diopter between the above groups of formulas,and the P values between the other formula groups were all<0.05,and the difference was statistically significant.In the pairwise comparison of the eight formulas,the Barrett Universal ?-Holladayl group had the smallest difference of 0.015D(P=0.543);the Haigis standard-Hoffer Q group had the largest difference of 1.010D(P<0.05).Conclusions:High repeatability and reproducibility were measured when measuring AL,ACD,K(2.5 mm and 3 mm diameter),LT,CCT ocular biological parameters.Among them,AL measurement precision is the highest.Low precision of PD and WTW.In the comparison of the diopter calculated by eight formulas of intraocular lens diopter,P value of Barrett universal ?-Holladayl,Barrett universal ?-SRK/T,Holladayl-SRK/T,Haigis optimized-SRK SHOWA group were all>0.05,and there was no significant difference in IOL diopter.Objective:To compare the detection rate of the axial length of the eyes of cataract patients by Tomey OA-2000 and Carl Zeiss IOLMaster500,and to evaluate the repeatability of OA-2000 in measuring the biological parameters of the eyes of cataract patients.The biological parameters of the eyes include AL,K,ACD,LT,CCT,PD and WTW.Method:This was a cross-sectional study.166 patients(270 eyes)with cataract were enrolled.AL was measured using OA-2000 and IOLMaster500 by the same operator.The data were recorded and the detection rates of AL were compared between the two devices by ?2 test,and the consistency of measurement results between two devices using Bland-Altman analysis.AL was measured by IOLMaster and the results were recorded firstly,followed AL,K,ACD,LT,CCT,PD and WTW data by OA-2000.In-subject standard deviation(Sw),intraclass correlation coefficient(ICC),coefficient of variation(CoV),and 2.77Sw and other statistical indicators were used to evaluate the repeatability of ocular biological parameters in cataract patients with OA-2000.Result:In terms of the detection rate of ocular biological parameters in cataract patients,among the 270 eyes measured,IOLMaster500 failed to detect AL in 37 eyes with a detection rate 86.30%,and OA-2000 failed to detect AL in 8 eyes,with a detection rate of 97.04%.The difference range of the AL measured by the two devices is(0.007±0.129)mm,and the 95%LoA range of AL is 0.01(-0.24?0.26)mm.OA-2000 has good repeatability in measuring ocular biological parameters of cataract patients such as AL,ACD,K(2.5mm and 3mm diameter),LT and CCT,but not PD and WTW.Conclusions:Compared with the partially coherent optical interference biometer IOLMaster500,the swept-source optical coherence tomography biometer OA-2000 has a higher detection rate of AL for cataract patients.The consistency of the two devices for measuring AL is good.OA-2000 has high repeatability for the measurement of AL,ACD,K,LT and CCT biological parameters in cataract patients,while low repeatability for PD and WTW.