Evaluation of Automated Segmentation Algorithm for Macular Volumetric Measurements of Eight Individual Retinal Layer Thickness

Background: We evaluated the performance of an automated algorithm available on a clinical OCT (Canon-HS100) for macular volumetric measurements of eight individual retinal layers. Methods and Analysis: Two consecutive three-dimensional scans were acquired on 29 subjects with healthy retinas. Thickness measurements were obtained from eight individual retinal layers in nine macular sectors based on Early Treatment Diabetic Retinopathy Study (ETDRS) protocol. The repeatability was evaluated using the within-subject standard deviation from which the repeatability limits (Rlimit) and coefficient of variation (CoV) were calculated. Results: The repeatability metrics varied among different layers and sectors. The variation among the sectors was larger in two of the outer layers (plexiform and nuclear layer) and the retinal nerve fiber layer. For the other five layers, the repeatability limit was less than 5µm and CoV was less than 7.5% in all nine ETDRS sectors. Conclusions: The repeatability of the OCT-HS100 to measure eight individual retinal layers is good in general. Nevertheless, the repeatability is not homogeneous among different layers and sectors. This needs to be taken into account while designing clinical measurement protocols.

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Multicenter reliability of semiautomatic retinal layer segmentation using OCT

Neurology Neuroimmunology & Neuroinflammation ◽

10.1212/nxi.0000000000000449 ◽

2018 ◽

Vol 5 (3) ◽

pp. e449 ◽

Cited By ~ 47

Author(s):

Timm Oberwahrenbrock ◽

Ghislaine L. Traber ◽

Sebastian Lukas ◽

Iñigo Gabilondo ◽

Rachel Nolan ◽

...

Keyword(s):

Spatial Distribution ◽

Outer Nuclear Layer ◽

Intraclass Correlation ◽

Plexiform Layer ◽

Retinal Layer ◽

Inner Plexiform Layer ◽

Automated Segmentation ◽

Fiber Layer ◽

Retinal Layers ◽

Manual Correction

ObjectiveTo evaluate the inter-rater reliability of semiautomated segmentation of spectral domain optical coherence tomography (OCT) macular volume scans.MethodsMacular OCT volume scans of left eyes from 17 subjects (8 patients with MS and 9 healthy controls) were automatically segmented by Heidelberg Eye Explorer (v1.9.3.0) beta-software (Spectralis Viewing Module v6.0.0.7), followed by manual correction by 5 experienced operators from 5 different academic centers. The mean thicknesses within a 6-mm area around the fovea were computed for the retinal nerve fiber layer, ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer, outer plexiform layer (OPL), and outer nuclear layer (ONL). Intraclass correlation coefficients (ICCs) were calculated for mean layer thickness values. Spatial distribution of ICC values for the segmented volume scans was investigated using heat maps.ResultsAgreement between raters was good (ICC > 0.84) for all retinal layers, particularly inner retinal layers showed excellent agreement across raters (ICC > 0.96). Spatial distribution of ICC showed highest values in the perimacular area, whereas the ICCs were poorer for the foveola and the more peripheral macular area. The automated segmentation of the OPL and ONL required the most correction and showed the least agreement, whereas differences were less prominent for the remaining layers.ConclusionsAutomated segmentation with manual correction of macular OCT scans is highly reliable when performed by experienced raters and can thus be applied in multicenter settings. Reliability can be improved by restricting analysis to the perimacular area and compound segmentation of GCL and IPL.

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Analysis of the Changes in Retinal Thickness in Eyes Undergoing Vitrectomy with Silicone Oil Tamponade

Journal of the Korean Ophthalmological Society ◽

10.3341/jkos.2021.62.7.969 ◽

2021 ◽

Vol 62 (7) ◽

pp. 969-975

Author(s):

Jae Hyun Kim ◽

Yo Sep Yoon ◽

Je Moon Woo ◽

Jung Kee Min

Keyword(s):

Silicone Oil ◽

Three Dimensional ◽

Plexiform Layer ◽

Retinal Layer ◽

Inner Plexiform Layer ◽

Fiber Layer ◽

Swept Source ◽

Before And After ◽

Silicone Oil Tamponade ◽

Thickness Measurements

Purpose: To investigate changes in the retinal layer thickness in rhegmatogenous retinal detachment (RRD) and intraocular foreign body (IOFB) patients undergoing successful pars plana vitrectomy (PPV) with silicone oil tamponade. Methods: This retrospective study included 28 eyes of 28 patients (RRD: 24 patients; IOFB: 4 patients) that were successfully repaired with PPV with silicone oil tamponade. The thickness measurements of the total retina, retinal nerve fiber layer (RNFL), and ganglion cell-inner plexiform layer (GC-IPL) were performed with swept-source optical coherence tomography in nine Early Treatment Diabetic Retinopathy Study subfields, using the wide three-dimensional mode before and after silicone oil tamponade removal. The measurements were compared and differences were analyzed with respect to normal fellow eyes. Results: The RNFL and GC-IPL thickness measurements decreased remarkably as the silicone oil tamponade period progressed, compared with the thickness of the total retinal layer. The average thicknesses of the total retina, RNFL, and GC-IPL were significantly greater in eyes in which the silicone oil had been removed than in those in which the silicone oil remained. Conclusions: Silicone oil tamponade can change the thickness of the retina layer. The longer the silicone oil is tamponaded, the more significant the reduction in thickness of the inner retinal layer.

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Agreement of different OCT scan directions for individual retinal-layer thickness measurements in multiple sclerosis subjects with prior unilateral optic neuritis

Scientific Reports ◽

10.1038/s41598-021-04611-y ◽

2022 ◽

Vol 12 (1) ◽

Author(s):

Alberto Domínguez-Vicent ◽

Maria Nilsson ◽

Rune Brautaset ◽

Abinaya Priya Venkataraman

Keyword(s):

Multiple Sclerosis ◽

Optic Neuritis ◽

Layer Thickness ◽

Retinal Layer ◽

Healthy Controls ◽

Fiber Layer ◽

Individual Layer ◽

History Of ◽

The Individual ◽

Thickness Measurements

AbstractThe similarities between horizontal and vertical Optical Coherence Tomography (OCT) scans for the individual retinal layer thickness measurements in the macula was evaluated. Two volumetric scans (B-scans oriented horizontally and vertically) were performed in 64 multiple sclerosis subjects with history of unilateral optic neuritis and 64 healthy controls. The agreement between the thickness measurements with horizontal and vertical OCT scans was evaluated in 3 groups of eyes: healthy controls, eyes with history of optic neuritis and the fellow eyes. The mean difference in individual layer thickness between the scans was smaller than the instrument’s axial resolution in all 3 groups. The limit of agreement (LoA) varied among the different layers and sectors analyzed and this trend was similar in all the groups. For the inner retinal layers (retinal nerve fiber layer to inner nuclear layer), the inner macular sectors had a larger LoA compared to the corresponding outer sectors. In the outer plexiform and nuclear layers, the central and inner sectors (except inner temporal) had LoA larger than the other sectors and layers. The larger LoA seen for different layers and sectors suggests that the scan direction must be same for the follow-up OCT measurements and in clinical studies.

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The effect of longstanding silicone oil on retina choroid and optic nerve in eyes with retinal detachment: an optical coherence tomography study

BMC Ophthalmology ◽

10.1186/s12886-021-02239-0 ◽

2022 ◽

Vol 22 (1) ◽

Author(s):

Umut Karaca ◽

Murat Kucukevcilioglu ◽

Ali Hakan Durukan ◽

Dorukcan Akincioglu

Keyword(s):

Retinal Detachment ◽

Nerve Fiber ◽

Silicone Oil ◽

Automatic Segmentation ◽

Retinal Layer ◽

Inner Plexiform Layer ◽

Fiber Layer ◽

Nerve Fiber Layer ◽

Retinal Layers ◽

Significant Difference

Abstract Background The study aims to evaluate peripapillary retinal nerve fiber layer thickness (RNFL-T), central macular thickness (MT), choroidal thickness (CT), and thickness of each retinal layer after automatic segmentation in patients who underwent retinal detachment (RD) repair with longstanding silicone oil tamponade. Methods We enrolled 33 patients who underwent complicated primary rhegmatogenous RD surgery and followed up with a long-term silicone tamponade were included in this retrospective comparative (case–control) study. RNFL-T, CT, and thickness of each retinal layer after automatic segmentation analysis were measured after the longstanding silicone removal surgery. Results The mean silicone oil removal time was 15.1 ± 15.2 (7–70) months. The overall average thickness of the RNFL was 90.7 ± 13.6 μm in the operated eyes and 118.3 ± 35.6 μm in the sound eyes, with a statistically significant difference. The overall average central MT was 186.3 ± 57.7 μm and was significantly lower in the operated eyes than in the sound eyes. Inner retinal layers of the study group showed a significant thinning in the nerve fiber layer, ganglion cell layer, inner plexiform layer, and inner nuclear layer as compared to that of the sound eyes. The subfoveal CT was 213.7 ± 86.6 μm in the study eyes and 217.7 ± 115.5 μm in the control eyes. There was no significant difference between the study eyes and controls. Conclusion The effects of silicone oil on the retina remain uncertain; however, morphological results in our study have shown direct or indirect silicone oil–induced toxicity, especially in the inner retinal layers.

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Inner Retinal Layer and Outer Retinal Layer Findings after Macular Hole Surgery Assessed by means of Optical Coherence Tomography

Journal of Ophthalmology ◽

10.1155/2019/3821479 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 4

Author(s):

Maria Vittoria Cicinelli ◽

Alessandro Marchese ◽

Francesco Bandello ◽

Michele Coppola

Keyword(s):

Optical Coherence Tomography ◽

Macular Hole ◽

Visual Outcome ◽

Clinical Findings ◽

Foveal Avascular Zone ◽

Retinal Layer ◽

Optical Coherence ◽

Fiber Layer ◽

Retinal Layers ◽

Retinal Thinning

Aim. To summarize the spectrum of optical coherence tomography (OCT) and OCT angiography (OCTA) features after full-thickness macular hole (MH) repair surgery. Methods. A PubMed engine search was carried out using the terms “Macular Hole,” “Optical Coherence Tomography,” and “Optical Coherence Tomography Angiography.” All reports published in English up to October 2018, irrespective of their publication status, were included. Tomographic signs analyzed were divided according to the involved portion of the retina in “inner retinal layers” and “external retinal layers.” Despite predominantly involving the inner retinal layers, cystoid macular edema (CME) has been treated as a separate entity. Finally, report on vessel density (VD) changes and the foveal avascular zone (FAZ) area modifications have been included. Results. Different clinical findings can be observed on OCT of patients who underwent MH repair surgery. There is general consent that retinal thinning involving primarily the retinal nerve fiber layer and the ganglion cell layer takes place after surgery. In the postoperative period, the outermost retinal layers get progressively restored. Persistent defects in the ellipsoid zone or in the external limiting membrane correlate with worse postoperative visual outcome. OCTA has globally demonstrated that eyes after MH closure show a reduction in macular and paramacular VD and smaller FAZ areas, compared with control or fellow eyes. Conclusion. Clinicians should be aware of the most common tomographic findings to properly manage each condition. In addition, significant advantages for the postoperative application of OCT and OCTA include noninvasiveness, rapid and simple execution, repeatability, and precise measurements.

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Quantitative Optical Coherence Tomography for Longitudinal Monitoring of Postnatal Retinal Development

10.20944/preprints202201.0139.v1 ◽

2022 ◽

Author(s):

Guangying Ma ◽

Jie Ding ◽

Tae-Hoon Kim ◽

Xincheng Yao

Keyword(s):

Optical Coherence Tomography ◽

Vision System ◽

Retinal Development ◽

Three Dimensional ◽

Plexiform Layer ◽

Retinal Layer ◽

Inner Plexiform Layer ◽

Optical Coherence ◽

Fiber Layer

A better study of the postnatal retinal development is not only essential for the in-depth understanding of the nature of the vision system but also may provide insights for treatment developments of eye conditions, such as retinopathy of premature (ROP). To date, quantitative analysis of postnatal retinal development is primarily limited to endpoint histological examination. This study is to validate in vivo optical coherence tomography (OCT) for longitudinal monitoring of postnatal retinal development in developing mouse eyes. Three-dimensional (3D) frame registration and super averaging were adopted to investigate the fine structure of the retina. Interestingly, a hyporeflective layer (HRL) between the nerve fiber layer (NFL) and inner plexiform layer (IPL) was observed in developing eyes and gradually disappeared with aging. To interpret the observed retinal layer kinetics, a model based on eyeball expansion, cell apoptosis, and retinal structural modification was proposed.

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Myopia and Regional Variations in Retinal Thickness in Healthy Eyes

Journal of Ophthalmic and Vision Research ◽

10.18502/jovr.v15i2.6735 ◽

2020 ◽

Author(s):

Feryal M. Zereid ◽

Uchechukwu L. Osuagwu

Keyword(s):

Regional Differences ◽

Retinal Thickness ◽

Retinal Layer ◽

Fiber Layer ◽

Foveal Thickness ◽

Spherical Equivalent Refraction ◽

The Mean ◽

Thickness Measurements ◽

Healthy Eyes ◽

Stratus Optical Coherence Tomography

Purpose: To investigate the effects of refraction on retinal thickness measurements at different locations and layers in healthy eyes of Saudi participants. Methods: Thirty-six randomly selected adults aged 27.0 ± 5.7 years who attended a Riyadh hospital from 2016 to 2017 were categorized into three groups: non-myopic (spherical equivalent refraction [SER], +1.00 to –0.50 diopters [D]), low myopic (SER, – 0.75 to –3.00D), and moderate to high myopic (SER ≤ –3.25D). Full, inner, and outer retinal thicknesses were measured at nine locations by spectral-domain stratus optical coherence tomography (Optovue Inc., Fremont, CA, USA) and were compared according to refractive group and sex. Results: The mean SERs for the non-myopia, low myopia, and moderate to high myopia groups were 0.2 ± 0.6, –1.5 ± 0.5, and –7.5 ± 1.9 D, respectively. Refractive error, but not sex, had significant effects on the retinal layer thickness measurements at different locations (P < 0.05). The parafoveal and outer retinal layers were significantly thicker than the perifoveal and inner retina layers in all groups (P < 0.05). The full foveal thickness was higher and the full parafoveal and perifoveal regions were thinner in moderate to high myopic eyes than in the non-myopic eyes (P < 0.05), but were similar to those in the low myopic eyes (P > 0.05). The foveal thicknesses measured in the inner and outer layers of the retina were higher but the thicknesses measured at the inner and outer layers of the parafoveal and perifoveal regions were lower in moderate to high myopic eyes. Conclusion: There were regional differences in the retinal layer thicknesses of healthy Saudi eyes, which was dependent on the central refractions. This is important when interpreting retinal nerve fiber layer thicknesses in myopia and disease management in Saudi participants.

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Epiretinal Membrane Surgery: Structural Retinal Changes Correlate with the Improvement of Visual Function

Journal of Clinical Medicine ◽

10.3390/jcm10010090 ◽

2020 ◽

Vol 10 (1) ◽

pp. 90

Author(s):

Andrea Cacciamani ◽

Pamela Cosimi ◽

Guido Ripandelli ◽

Marta Di Nicola ◽

Fabio Scarinci

Keyword(s):

Visual Acuity ◽

Visual Function ◽

Epiretinal Membrane ◽

Outer Nuclear Layer ◽

Plexiform Layer ◽

Retinal Layer ◽

Inner Plexiform Layer ◽

Fiber Layer ◽

Retinal Layers ◽

Sd Oct

Several parameters have been studied for identifying the visual outcomes after pars plana vitrectomy (PPV) for epiretinal membrane (ERM) peeling. This retrospective study aimed to analyze structural retinal changes with spectral domain-optical coherence tomography (SD-OCT) and their correlations with visual acuity improvement in patients with ERM undergoing PPV. Twenty-one pseudophakic eyes were enrolled in the study. Ophthalmic evaluations included best corrected visual acuity (BCVA) and retinal layer thickness measurements with SD-OCT. The segmentation of the retina was divided into four parts: the inner retinal layer (IRL), composed of an internal limiting membrane, retinal nerve fiber layer, ganglion cell layer, and inner plexiform layer; inner nuclear layer (INL); outer plexiform layer (OPL); and outer nuclear layer (ONL). Correlations between changes in retinal layer thicknesses and BCVA were explored over a 6 month follow-up period. The postoperative thickness decrease of the INL was significantly correlated with thickness changes in all other measured retinal layers (p < 0.001). Non-parametric linear regression showed that postoperative improvement in BCVA was associated with a postoperatively decreased thickness in the IRL (p = 0.021), INL (p = 0.039), and OPL (p = 0.021). In eyes undergoing PPV, postoperative thickness decreases of the IRL, INL, and OPL were correlated with visual acuity improvements. Re-compaction of these retinal layers after relieving ERM-induced traction may be an important factor in postoperative visual function improvement.

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