Repeatability and agreement of white-to-white measurements between slit-scanning tomography, infrared biometry, dual rotating Scheimpflug camera/Placido disc tomography, and swept source anterior segment optical coherence tomography

Purpose To assess the agreement and repeatability of horizontal visible iris diameter (HVID) or white-to-white (WTW) measurements between four imaging modalities; combination slit scanning elevation/Placido tomography, infrared biometry, dual rotating scheimpflug camera/Placido tomography, and swept source anterior segment optical coherence tomography (AS-OCT). Methods A prospective study of 35 right eyes of healthy volunteers were evaluated using the Orbscan IIz, IOL Master 700, Galilei G2, and DRI Triton OCT devices. The inter-device agreement and repeatability of HVID/WTW measurements for each device were analysed. Results Mean HVID/WTW values obtained by the Orbscan IIz, IOL Master 700, Galilei G2 and DRI Triton OCT were 11.77 ± 0.40 mm, 12.40 ± 0.43 mm, 12.25 ± 0.42 mm, and 12.42 ± 0.47 mm, respectively. All pairwise comparisons revealed statistically significant differences in mean HVID/WTW measurements (p = <0.01) except for the IOL Master 700—DRI OCT Triton pair (p = 0.56). Mean differences showed that the DRI Triton OCT produced the highest HVID/WTW values, followed by the IOL Master 700, Galilei G2 and Orbscan IIz, respectively. The limits of agreement were large on all device pairs. There was high repeatability for all devices (ICC ≥ 0.980). The highest repeatability was seen in the Galilei G2 (ICC = 0.995) and lowest in the Orbscan IIz (ICC = 0.980). Conclusions The four devices exhibit high repeatability, but should not be used interchangeably for HVID/WTW measurements in clinical practice.

Download Full-text

Assessment of corneal thickness measurement using swept-source Fourier-domain anterior segment optical coherence tomography and Scheimpflug camera

Journal of Cataract & Refractive Surgery ◽

10.1016/j.jcrs.2012.05.004 ◽

2012 ◽

Vol 38 (7) ◽

pp. 1305-1306 ◽

Cited By ~ 2

Author(s):

Jinhai Huang ◽

Yifan Feng ◽

Qinmei Wang ◽

Konrad Pesudovs

Keyword(s):

Optical Coherence Tomography ◽

Corneal Thickness ◽

Anterior Segment ◽

Thickness Measurement ◽

Fourier Domain ◽

Optical Coherence ◽

Swept Source ◽

Scheimpflug Camera

Download Full-text

Displacement between anterior chamber width obtained by swept-source anterior segment optical coherence tomography and white-to-white distance

PLoS ONE ◽

10.1371/journal.pone.0251990 ◽

2021 ◽

Vol 16 (5) ◽

pp. e0251990

Author(s):

Teerajet Taechameekietichai ◽

Anwell Nguyen ◽

Sunee Chansangpetch ◽

Shan C. Lin

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Intraclass Correlation ◽

Anterior Segment ◽

Mean Difference ◽

Optical Coherence ◽

Limits Of Agreement ◽

Swept Source ◽

The Mean ◽

The Relationship

Purpose To determine the relationship between the external limbal location, represented by white-to-white (WTW) distance, and the actual angle location, represented by spur-to-spur (STS) and angle-to-angle (ATA) distances. Methods 166 eyes from 166 participants were imaged using CASIA2 anterior chamber optical coherence tomography (AS-OCT) and LenStar LS 900 optical biometer. The horizontal ATA and STS were measured using the swept-source Fourier-domain AS-OCT (CASIA2). The horizontal WTW was automatically measured using LenStar. The displacement lengths (DL) between WTW-STS and WTW-ATA were calculated. Bland-Altman plots and intraclass correlation were performed. Results The study showed that WTW has a positive correlation with STS (ICC = 0.82, p<0.001) and ATA (ICC = 0.82, p<0.001). The Bland-Altman analysis demonstrated that the mean difference of WTW-STS is 0.10 mm (95% CI 0.06 to 0.14 mm) with limits of agreement of -0.42 to 0.63 mm between WTW and STS, and the mean difference of WTW-ATA is 0.10 mm (95% CI 0.06 to 0.15 mm) with limits of agreement of -0.48 to 0.64 mm between WTW and ATA. Linear regression with adjustment showed that a WTW value greater than 12.07 mm is associated with a greater DL (WTW-STS DL ß 0.18, p = 0.003; WTW-ATA DL ß 0.14, p = 0.03). Conclusions Greater WTW was significantly associated with higher displacement of WTW from the two distances representing anterior chamber width. External limbal location may not accurately represent the actual angle location in eyes with larger WTW.

Download Full-text

Comparison of a New Swept-Source Anterior Segment Optical Coherence Tomography and a Scheimpflug Camera for Measurement of Corneal Curvature

Cornea ◽

10.1097/ico.0000000000002280 ◽

2020 ◽

Vol 39 (7) ◽

pp. 818-822 ◽

Cited By ~ 3

Author(s):

Ting Zhang ◽

Yijing Zhou ◽

Charlotte Aimee Young ◽

Aiming Chen ◽

Guangming Jin ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Anterior Segment ◽

Optical Coherence ◽

Corneal Curvature ◽

Swept Source ◽

Scheimpflug Camera

Download Full-text

Repeatability of automated measurements by a new anterior segment optical coherence tomographer and biometer and agreement with standard devices

Scientific Reports ◽

10.1038/s41598-020-79674-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Domenico Schiano-Lomoriello ◽

Kenneth J. Hoffer ◽

Irene Abicca ◽

Giacomo Savini

Keyword(s):

Intraclass Correlation ◽

Anterior Segment ◽

Consecutive Series ◽

Optical Coherence ◽

Limits Of Agreement ◽

Automated Measurements ◽

Deviation Coefficient ◽

Corneal Diameter ◽

High Repeatability ◽

Good Agreement

AbstractWe assess repeatability of automatic measurements of a new anterior segment optical coherence tomographer and biometer (ANTERION) and their agreement with those provided by an anterior segment-optical coherence tomography device combined with Placido-disk corneal topography (MS-39) and a validated optical biometer (IOLMaster 500). A consecutive series of patients underwent three measurements with ANTERION and one with MS-39. A subgroup of patients underwent biometry also with IOLMaster 500. Repeatability was assessed by means of within-subject standard deviation, coefficient of variation (COV), and intraclass correlation coefficient (ICC). Agreement was investigated with the 95% limits of agreement. Paired t-test and Wilcoxon matched-pairs test were performed to compare the measurements of the different devices. Repeatability of ANTERION measurements was high, with ICC > 0.98 for all parameters except astigmatism (0.963); all parameters apart from those related to astigmatism revealed a COV < 1%. Repeatability of astigmatism improved when only eyes whose keratometric astigmatism was higher than 1.0 D were investigated. Most measurements by ANTERION and MS-39 showed good agreement. No significant differences were found between measurements by ANTERION and IOLMaster, but for corneal diameter. ANTERION revealed high repeatability of automatic measurements and good agreement with both MS-39 and IOLMaster for most parameters.

Download Full-text

Objective quantification of lens nuclear opacities using swept-source anterior segment optical coherence tomography

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2020-318334 ◽

2021 ◽

pp. bjophthalmol-2020-318334

Author(s):

Wei Wang ◽

Jiaqing Zhang ◽

Xiaoxun Gu ◽

Xiaoting Ruan ◽

Xiaoyun Chen ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Visual Acuity ◽

Anterior Segment ◽

Training Dataset ◽

Dissipated Energy ◽

Nuclear Density ◽

Optical Coherence ◽

Nuclear Cataract ◽

Swept Source ◽

Ultrasonic Time

Background/aimsThe primary objective is to quantify the lens nuclear opacity using swept-source anterior segment optical coherence tomography (SS-ASOCT) and to evaluate its correlations with Lens Opacities Classification System III (LOCS-III) system and surgical parameters. The secondary objective is to assess the diagnostic performance for hard nuclear cataract.MethodsThis cross-sectional study included 1222 patients eligible for cataract surgery (1222 eyes). The latest SS-ASOCT (CASIA-2) was used to obtain high-resolution lens images, and the average nuclear density (AND) and maximum nuclear density (MND) were measured by a custom ImageJ software. Spearman’s correlations analysis was used to assess associations of AND/MND with LOCS-III nuclear scores, visual acuity and surgical parameters. The subjects were then split randomly (9:1) into the training dataset and validating dataset. Receiver operating characteristic curves and calibration curves were constructed for the classification on hard nuclear cataract.ResultsThe AND and MND from SS-ASOCT images were significantly correlated with nuclear colour scores (AND: r=0.716; MND: r=0.660; p<0.001) and nuclear opalescence scores (AND: r=0.712; MND: r=0.655; p<0.001). The AND by SS-ASOCT images had the highest values of Spearman’s r for preoperative corrected distance visual acuity (r=0.3131), total ultrasonic time (r=0.3481) and cumulative dissipated energy (r=0.4265). The nuclear density had good performance in classifying hard nuclear cataract, with area under the curves of 0.859 (0.831–0.886) for AND and 0.796 (0.768–0.823) for MND.ConclusionObjective and quantitative evaluation of the lens nuclear density using SS-ASOCT images enable accurate diagnosis of hard nuclear cataract.

Download Full-text