Comparison of composite and segmental methods for acquiring optical axial length with swept-source optical coherence tomography

Purpose: To investigate the morphologic features and identify the risk factors of myopic choroidal neovascularization (CNV).Methods: Eighty-eight eyes of 69 consecutive patients with myopic CNV were included in this study. About 109 eyes of 78 pathologic myopia patients without myopic CNV were randomly selected as the control group. Morphologic features and parameters including scleral thickness (ST), choroidal thickness (CT), posterior staphyloma height and the presence of scleral perforating vessels were obtained and measured by swept-source optical coherence tomography (SS-OCT). Binary logistic regression analysis was performed to identify the risk factors for myopic CNV.Results: Patients with myopic CNV had relatively shorter axial length (P < 0.001) and thicker sclera (P < 0.001) compared to those without. After adjusting age, gender and axial length, thick sclera (OR = 1.333, P < 0.001 per 10-μm increase) and thin choroid (OR = 0.509, P < 0.001 per 10-μm increase) were associated with the presence of myopic CNV. Scleral perforating vessels were detected in the area of myopic CNV in 78.67% of the subjects.Conclusions: A relatively thicker sclera and a thinner choroid are the biological indicators for myopic CNV on SS-OCT. Scleral perforating vessels may also play a pivotal role in the formation of myopic CNV.

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Evaluation of axial length measurement using enhanced retina visualization mode of the swept-source optical coherence tomography biometer in dense cataract

Ophthalmic Research ◽

10.1159/000515054 ◽

2021 ◽

Author(s):

Akeno Tamaoki ◽

Takashi Kojima ◽

Asato Hasegawa ◽

Mana Yamamoto ◽

Tatsushi Kaga ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Axial Length ◽

Preoperative Evaluation ◽

Case Series ◽

Rank Test ◽

P Value ◽

Optical Coherence ◽

Acquisition Rate ◽

Swept Source ◽

Standard Mode

Introduction: It has been reported that even using the swept-source optical coherence biometer, it is challenging to measure the axial length (AL) in cases with advanced cataracts. The enhanced retina visualization (ERV) mode, which is equipped with OCTB1 (ARGOS), shifts the peak of measurement sensitivity to the retina side so that the AL can be measured even if the light energy is attenuated. The aim of the present study was to evaluate the accuracy and efficacy of the ERV mode in measuring the AL of dense cataracts. Methods: This was a single-center retrospective observational case series conducted in Japan. We included 213 eyes of 213 consecutive patients with advanced cataracts who underwent preoperative evaluation. The AL was measured before and after surgery using two swept-source (SS) optical coherence tomography biometers (OCTB1, OCTB2; IOLMaster 700). Cases in which OCTB1 the standard mode failed to measure AL, OCTB1 with the ERV mode was used instead. Primary outcome measures were the acquisition rate and the AL measurement accuracy using the ERV mode. The Chi-square test, the Kruskal-Wallis test, and the Wilcoxon signed-rank test were used to compare the acquisition rate, differences between pre- and post-operative AL values, respectively. In the ERV subgroup, Bland-Altman plots were used to compare the pre- and post-operative AL values measured using OCTB1-ERV mode. A p-value of less than 5% was considered statistically significant. Results: The AL acquisition rate was not significantly different between OCTB1 with the standard mode and OCTB2. The AL of 65 eyes (30.5%) could not be measured using OCTB1 with the standard mode. Conversely, the AL of 51 of these eyes (78.5%) was successfully measured using OCTB1 with the ERV mode. In these 51 eyes, a difference of ≤0.2 mm and of ≤0.1 mm between pre- and post-operative AL measurements was observed in 40 (78.4%) and 30 eyes (58.8%), respectively. The Bland-Altman plot found no systematic error between pre- and post-operative AL values measured using the ERV mode. Conclusion: In patients with dense cataracts, AL measurement using the standard mode of an SS-OCT biometer is challenging. Furthermore, the ERV mode could be promising for AL measurement in such cases.

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Efficacy of Swept-source Optical Coherence Tomography in Axial Length Measurement for Advanced Cataract Patients

Optometry and Vision Science ◽

10.1097/opx.0000000000001491 ◽

2020 ◽

Vol 97 (3) ◽

pp. 186-191

Author(s):

Chareenun Chirapapaisan ◽

Sabong Srivannaboon ◽

Pratuangsri Chonpimai

Keyword(s):

Optical Coherence Tomography ◽

Axial Length ◽

Length Measurement ◽

Optical Coherence ◽

Swept Source ◽

Cataract Patients

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Choroidal thickness measured with swept source optical coherence tomography in posterior staphyloma strongly correlates with axial length and visual acuity

International Journal of Retina and Vitreous ◽

10.1186/s40942-019-0166-y ◽

2019 ◽

Vol 5 (1) ◽

Cited By ~ 4

Author(s):

K. V. Chalam ◽

Kumar Sambhav

Keyword(s):

Optical Coherence Tomography ◽

Visual Acuity ◽

Axial Length ◽

Choroidal Thickness ◽

Optical Coherence ◽

Swept Source ◽

Posterior Staphyloma

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Axial Length Measurement Failure Rates With Biometers Using Swept-Source Optical Coherence Tomography Compared to Partial-Coherence Interferometry and Optical Low-Coherence Interferometry

American Journal of Ophthalmology ◽

10.1016/j.ajo.2016.09.019 ◽

2017 ◽

Vol 173 ◽

pp. 64-69 ◽

Cited By ~ 27

Author(s):

Colm McAlinden ◽

Qinmei Wang ◽

Rongrong Gao ◽

Weiqi Zhao ◽

Ayong Yu ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Axial Length ◽

Length Measurement ◽

Partial Coherence ◽

Optical Coherence ◽

Failure Rates ◽

Swept Source ◽

Partial Coherence Interferometry ◽

Low Coherence ◽

Low Coherence Interferometry

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Correlation of Choroidal Thickness and Volume Measurements with Axial Length and Age Using Swept Source Optical Coherence Tomography and Optical Low-Coherence Reflectometry

BioMed Research International ◽

10.1155/2014/639160 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 31

Author(s):

Janusz Michalewski ◽

Zofia Michalewska ◽

Zofia Nawrocka ◽

Maciej Bednarski ◽

Jerzy Nawrocki

Keyword(s):

Optical Coherence Tomography ◽

Axial Length ◽

Choroidal Thickness ◽

Optical Coherence ◽

Swept Source ◽

Low Coherence ◽

Mapping Software ◽

Volume Measurements ◽

Changes Over Time ◽

Optical Low Coherence Reflectometry

Purpose. To report choroidal thickness and volume in healthy eyes using swept source optical coherence tomography (SS-OCT).Methods. A prospective observational study of 122 patients examined with swept source OCT (DRI-OCT, Topcon, Japan). In each eye, we performed 256 horizontal scans, 12 mm in length and centered on the fovea. We calculated choroidal thickness manually with a built-in caliper and automatically using DRI-OCT mapping software. Choroidal volume was also automatically calculated. We measured axial length with optical low-coherence reflectometry (Lenstar LS 900, Haag-Streit, Switzerland).Results. The choroid has focally increased thickness under the fovea. Choroid was thinnest in the outer nasal quadrant. In stepwise regression analysis, age was estimated as the most significant factor correlating with decreased choroidal thicknessF=23.146, P<0.001followed by axial lengthF=4.902, P=0.03. Refractive error was not statistically significantF=1.16, P=0.28.Conclusions. SS-OCT is the first commercially available system that can automatically create choroidal thickness and volume maps. Choroidal thickness is increased at the fovea and is thinnest nasally. Age and axial length are critical for the estimation of choroidal thickness and volume. Choroidal measurements derived from SS-OCT images have potential value for objectively documenting disease-related choroidal thickness abnormalities and monitoring progressive changes over time.

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