Immune Analysis Using Vitreous Optical Coherence Tomography Imaging in Rats with Steroid-Induced Glaucoma.

Glaucoma is a multifactorial pathology involving the immune system. The subclinical immune response plays a homeostatic role in healthy situations, but in pathological situations, it produces imbalances. Optical coherence tomography detects immune cells in the vitreous as hyperreflective opacities and these are subsequently characterised by computational analysis. This study monitors the changes in immunity in the vitreous in two steroid-induced glaucoma (SIG) animal models created with drug delivery systems (microspheres loaded with dexamethasone and dexamethasone/fibronectin), comparing both sexes and healthy controls over six months. SIG eyes tended to present greater intensity and a higher number of vitreous opacities (p < 0.05), with dynamic fluctuations in the percentage of isolated cells (10 µm2), non-activated cells (10-50 µm2), activated cells (50-250 µm2) and cell complexes (>250 µm2). Both SIG models presented an anti-inflammatory profile, with non-activated cells being the largest population in this study. However, smaller opacities (isolated cells) seemed to be the first responder to noxa since they were the most rounded (recruitment), coinciding with peak intraocular pressure increase, and showed the highest mean Intensity (intracellular machinery), even in the contralateral eye, and a major change in orientation (motility). Studying the features of hyperreflective opacities in the vitreous using OCT could be a useful biomarker of glaucoma.

Corrigendum to "Laponite for biomedical applications: An ophthalmological perspective" [Mater. Today Bio 24 (2024) 100935].

[This corrects the article DOI: 10.1016/j.mtbio.2023.100935.].

Chronic Glaucoma Induced in Rats by a Single Injection of Fibronectin-Loaded PLGA Microspheres: IOP-Dependent and IOP-Independent Neurodegeneration.

To evaluate a new animal model of chronic glaucoma induced using a single injection of fibronectin-loaded biodegradable PLGA microspheres (Ms) to test prolonged therapies. 30 rats received a single injection of fibronectin-PLGA-Ms suspension (MsF) in the right eye, 10 received non-loaded PLGA-Ms suspension (Control), and 17 were non-injected (Healthy). Follow-up was performed (24 weeks), evaluating intraocular pressure (IOP), optical coherence tomography (OCT), histology and electroretinography. The right eyes underwent a progressive increase in IOP, but only induced cohorts reached hypertensive values. The three cohorts presented a progressive decrease in ganglion cell layer (GCL) thickness, corroborating physiological age-related loss of ganglion cells. Injected cohorts (MsF > Control) presented greater final GCL thickness. Histological exams explain this paradox: the MsF cohort showed lower ganglion cell counts but higher astrogliosis and immune response. A sequential trend of functional damage was recorded using scotopic electroretinography (MsF > Control > Healthy). It seems to be a function-structure correlation: in significant astrogliosis, early functional damage can be detected by electroretinography, and structural damage can be detected by histological exams but not by OCT. Males presented higher IOP and retinal and GCL thicknesses and lower electroretinography. A minimally invasive chronic glaucoma model was induced by a single injection of biodegradable Ms.

Mimicking chronic glaucoma over 6 months with a single intracameral injection of dexamethasone/fibronectin-loaded PLGA microspheres.

To create a chronic glaucoma animal model by a single intracameral injection of biodegradable poly lactic-co-glycolic acid (PLGA) microspheres (Ms) co-loaded with dexamethasone and fibronectin (MsDexaFibro). MsDexaFibro were prepared by a water-in-oil-in-water emulsion method including dexamethasone in the organic phase and fibronectin in the inner aqueous phase. To create the chronic glaucoma model, an interventionist and longitudinal animal study was performed using forty-five Long Evans rats (4-week-old). Rats received a single intracameral injection of MsDexafibro suspension (10%w/v) in the right eye. Ophthalmological parameters such as clinical signs, intraocular pressure (IOP), neuro-retinal functionality by electroretinography (ERG), retinal structural analysis by optical coherence tomography (OCT), and histology were evaluated up to six months. According to the results obtained, the model proposed was able to induce IOP increasing in both eyes over the study, higher in the injected eyes up to 6 weeks (p < 0.05), while preserving the ocular surface. OCT quantified progressive neuro-retinal degeneration (mainly in the retinal nerve fiber layer) in both eyes but higher in the injected eye. Ganglion cell functionality decreased in injected eyes, thus smaller amplitudes in PhNR were detected by ERG. In conclusion, a new chronic glaucoma animal model was created by a single injection of MsDexaFibro very similar to open-angle glaucoma occurring in humans. This model would impact in different fields such as ophthalmology, allowing long period of study of this pathology; pharmacology, evaluating the neuroprotective activity of active compounds; and pharmaceutical technology, allowing the correct evaluation of the efficacy of long-term sustained ocular drug delivery systems.

Toric intraocular lens implantation vs femtosecond laser-assisted arcuate keratotomy for correction of moderate astigmatism in cataract surgery.

PURPOSE: To compare toric intraocular lens (TIOL) implantation and femtosecond laser-assisted arcuate keratotomy (FSAK) during phacoemulsification surgery in correction of moderate astigmatism. SETTING: Clinical research study. DESIGN: Prospective randomized comparison study. METHODS: Patients with age-related cataract and moderate preoperative corneal astigmatism of 1.25 to 3.0 diopters (D) were randomized into a TIOL implantation group and an FSAK group with symmetrical paired corneal arcuate keratotomies. The preoperative evaluation included corrected distance visual acuity (CDVA), corneal topography, autokeratometry, and ocular biometry. Postoperative examinations were performed at 1 month and 3 months and included CDVA and uncorrected distance visual acuity, manifest refraction, autokeratometry, and corneal topography. Vector analysis of astigmatic changes was performed using the Alpins vector method. RESULTS: This study comprised 75 eyes from 67 patients. The mean residual refractive astigmatism at 3 months was -0.63 ± 0.55 D in the TIOL group and -0.90 ± 0.53 D in the FSAK group ( P = .037) and was ≤1.00 D in 32 eyes (84%) and 25 eyes (64%), respectively. There were no statistically significant differences between the 2 groups in difference vector, angle of error, magnitude error, or correction index in the 3-month follow-up. The index of success was 0.32 ± 0.33 D in the TIOL group and 0.48 ± 0.29 D in the FSAK group ( P = .029). CONCLUSIONS: TIOL implantation showed better results in correcting moderate astigmatism. Despite this, FSAK is shown to be a safe technique for reducing astigmatism.

Ocular related emergencies in Spain during the COVID-19 pandemic, a multicenter study.

PURPOSE: To evaluate ophthalmological emergencies (OE) during the COVID-19 pandemic comparing them with the same period of the previous year. METHODS: Retrospective observational study of all OE visits in four tertiary hospitals in Spain comparing data from March 16th to April 30th, 2020 (COVID-19 period) and the same period of 2019 (pre-COVID-19 period). Severity of the conditions was assessed following Channa et al. publication. Data on demographics, diagnosis and treatments were collected from Electronic Medical Records. RESULTS: During lockdown, OE significantly declined by 75.18%, from 7,730 registered in the pre-COVID-19 period to 1,928 attended during the COVID-19 period (p < 0.001). In 2019, 23.86% of visits were classified as emergent, 59.50% as non-emergent, and 16.65% could not be determined. In 2020, the percentage of emergent visits increased up to 29.77%, non-emergent visits significantly decreased to 52.92% (p < 0.001), and 17.31% of the visits were classified as "could not determine". During the pandemic, people aged between 45 and 65 years old represented the largest attending group (37.89%), compared to 2019, where patients over 65 years were the majority (39.80%). In 2019, most frequent diagnosis was unspecified acute conjunctivitis (11.59%), followed by vitreous degeneration (6.47%), and punctate keratitis (5.86%). During the COVID-19 period, vitreous degeneration was the first cause for consultation (9.28%), followed by unspecified acute conjunctivitis (5.63%) and punctate keratitis (5.85%). CONCLUSIONS: OE visits dropped significantly during the pandemic in Spain (75.18%), although more than half were classified as non-urgent conditions, indicating a lack of understanding of the really emergent ocular pathologies among population.

Influence of Sex on Neuroretinal Degeneration: Six-Month Follow-Up in Rats With Chronic Glaucoma.

Purpose: To evaluate differences by sex in the neuroretina of rats with chronic glaucoma over 24 weeks of follow-up, and to assess by sex the influence on neurodegeneration of different methods of inducing ocular hypertension. Methods: Forty-six Long-Evans rats-18 males and 28 females-with induced chronic glaucoma were analyzed. Glaucoma was achieved via 2 models: repeatedly sclerosing the episcleral veins (9 male/14 female) or by injecting poly(lactic-co-glycolic acid) microspheres measuring 20 to 10 µm (Ms20/10) into the anterior chamber (9 male/14 female). The IOP was measured weekly by tonometer; neuroretinal function was recorded by dark/light-adapted electroretinography at baseline and weeks 12 and 24; and structure was analyzed by optical coherence tomography using the retina posterior pole, retinal nerve fiber layer and ganglion cell layer protocols at baseline and weeks 8, 12, 18, and 24. Results: Males showed statistically significant (P < 0.05) higher IOP in both chronic glaucoma models, and greater differences were found in the episcleral model at earlier stages. Males with episclerally induced glaucoma showed a statistically higher increase in retinal thickness in optical coherence tomography recordings than females and also when comparing Ms20/10 at 12 weeks. Males showed a higher percentage of retinal nerve fiber layer thickness loss in both models. Ganglion cell layer thickness loss was only detected in the Ms20/10 model. Males exhibited worse dark/light-adapted functionality in chronic glaucoma models, which worsened in the episcleral sclerosis model at 12 weeks, than females. Conclusions: Female rats with chronic glaucoma experienced lower IOP and structural loss and better neuroretinal functionality than males. Sex and the ocular hypertension-inducing method influenced neuroretinal degeneration.

Influence of Chronic Ocular Hypertension on Emmetropia: Refractive, Structural and Functional Study in Two Rat Models.

Chronic ocular hypertension (OHT) influences on refraction in youth and causes glaucoma in adulthood. However, the origin of the responsible mechanism is unclear. This study analyzes the effect of mild-moderate chronic OHT on refraction and neuroretina (structure and function) in young-adult Long-Evans rats using optical coherence tomography and electroretinography over 24 weeks. Data from 260 eyes were retrospectively analyzed in two cohorts: an ocular normotension (ONT) cohort (<20 mmHg) and an OHT cohort (>20 mmHg), in which OHT was induced either by sclerosing the episcleral veins (ES group) or by injecting microspheres into the anterior chamber. A trend toward emmetropia was found in both cohorts over time, though it was more pronounced in the OHT cohort (p < 0.001), especially in the ES group (p = 0.001) and males. IOP and refraction were negatively correlated at week 24 (p = 0.010). The OHT cohort showed early thickening in outer retinal sectors (p < 0.050) and the retinal nerve fiber layer, which later thinned. Electroretinography demonstrated early supranormal amplitudes and faster latencies that later declined. Chronic OHT accelerates emmetropia in Long-Evans rat eyes towards slowly progressive myopia, with an initial increase in structure and function that reversed over time.

Ganglion Cell and Retinal Nerve Fiver Layers Correlated with Time Disease of Bipolar Disorder Using 64 Cell Grid OCT Tool.

MATERIALS AND METHODS: Twenty-five eyes of 25 patients with bipolar disorder and 74 eyes of 74 healthy controls underwent retinal measurements of retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) thickness. Measurements were obtained using the Spectralis-OCT device with the new Posterior Pole protocol which assesses the macular area by analyzing retinal thickness in a grid of 64 (8*8) cells. RESULTS: Significant differences (p < 0.05) in RNFL and GCL thickness were found between BD patients and healthy controls, in parafoveal and perifoveal cells respectively. Significant inverse correlations were found between RNFL and GCL thinning at their thickest location and the duration of bipolar disorder. Several predictive variables were observed with a binary logistic regression for the presence/absence of BD: cell 1.3 RNFL (p = 0.028) and GCL in cells 7.8 (p = 0.012), 2.7 (p = 0.043) and 1.3 (p = 0.047). CONCLUSION: Posterior Pole OCT protocol is a useful tool to assess changes in the inner retinal layers in bipolar disorder. These observed changes, especially those affecting the GCL, may be associated with disease evolution and may be predictive of the presence of the disease. OCT data could potentially be a useful tool for clinicians to diagnose and monitor BD patients.

Physiological changes in retinal layers thicknesses measured with swept source optical coherence tomography.

PURPOSE: To evaluate the physiological changes related with age of all retinal layers thickness measurements in macular and peripapillary areas in healthy eyes. METHODS: Wide protocol scan (with a field of view of 12x9 cm) from Triton SS-OCT instrument (Topcon Corporation, Japan) was performed 463 heathy eyes from 463 healthy controls. This protocol allows to measure the thickness of the following layers: Retina, Retinal nerve fiber layer (RNFL), Ganglion cell layer (GCL +), GCL++ and choroid. In those layers, mean thickness was compared in four groups of ages: Group 1 (71 healthy subjects aged between 20 and 34 years); Group 2 (65 individuals aged 35-49 years), Group 3 (230 healthy controls aged 50-64 years) and Group 4 (97 healthy subjects aged 65-79 years). RESULTS: The most significant thinning of all retinal layers occurs particularly in the transition from group 2 to group 3, especially in temporal superior quadrant at RNFL, GCL++ and retinal layers (p≤0.001), and temporal superior, temporal inferior, and temporal half in choroid layer (p<0.001). Curiously group 2 when compared with group 1 presents a significant thickening of RNFL in temporal superior quadrant (p = 0.001), inferior (p<0.001) and temporal (p = 0.001) halves, and also in nasal half in choroid layer (p = 0.001). CONCLUSIONS: Excepting the RNFL, which shows a thickening until the third decade of life, the rest of the layers seem to have a physiological progressive thinning.

Reproducibility of retinal and choroidal measurements using swept-source optical coherence tomography in patients with Parkinson's disease / Reprodutibilidade das medições da retina e da coroideia utilizando a tomografia de coerência ótica Swept-Source em pacientes com a doença de Parkinson

ABSTRACT Purpose: To assess the reproducibility of retinal and choroidal measurements in the macular and peripapillary areas using swept-source optical coherence tomography in patients with Parkinson's disease. Methods: A total of 63 eyes of 63 patients with idiopathic Parkinson's disease were evaluated using a three-dimensional protocol of swept-source optical coherence tomography. The following layers were analyzed: full retinal thickness, retinal nerve fiber layer, ganglion cell layer, and choroid. The coefficient of variation was calculated for every measurement. Results: In the macular area, the mean coefficients of variation of retinal thickness, ganglion cell layer + thickness, and choroidal thickness were 0.40%, 0.84%, and 2.09%, respectively. Regarding the peripapillary area, the mean coefficient of variation of the retinal nerve fiber layer thickness was 2.78. The inferior quadrant showed the highest reproducibility (coefficient of variation= 1.62%), whereas the superonasal sector showed the lowest reproducibility (coefficient of variation= 8.76%). Conclusions: Swept-source optical coherence tomography provides highly reproducible measurements of retinal and choroidal thickness in both the macular and peripapillary areas. The reproducibility is higher in measurements of retinal thickness versus choroidal thickness.

RESUMO Objetivo: Avaliar a reprodutibilidade das medições da retina e da coroide nas áreas macular e peripapilar utilizando a tomografia de coerência ótica com fonte de varredura pacientes com doença de Parkinson. Métodos: Um total de 63 olhos de 63 pacientes com doença de Parkinson idiopática foram avaliados usando um protocolo 3D de tomografia de coerência ótica de fonte Triton Swept. Foram analisadas as seguintes camadas: espessura retiniana total, camada de fibras nervosas da retina, camada de células ganglionares e coróide. O coeficiente de variação foi calculado para cada medição. Resultados: Na área macular, os coeficientes médios de variação da espessura da retina, da camada de células ganglionares + espessura e da espessura da coróide foram de 0,40%, 0,84% e 2,09%, respectivamente. Em relação à área peripapilar, o coeficiente médio de variação da espessura da camada de fibras nervosas da retina foi de 2,78%. O quadrante inferior apresentou a maior reprodutibilidade (coeficiente de variação= 1,62%), enquanto o setor superonasal apresentou a menor reprodutibilidade (coeficiente de variação= 8,76%). Conclusões: A tomografia de coerência ótica de fonte Triton Swept fornece medições altamente reprodutíveis da espessura da retina e da coroide nas áreas macular e peripapilar. A reprodutibilidade é maior nas medidas da espessura da retina versus a espessura da coróide.

Diagnostic capability of a linear discriminant function applied to a novel Spectralis OCT glaucoma-detection protocol.

BACKGROUND: Bruch membrane opening-minimum rim width (BMO-MRW) assessment offers a new diagnostic use in glaucoma patients of the Glaucoma Module Premium Edition (GMPE) available for the Spectralis optical coherence tomography (OCT) system. The objective of our research was to evaluate the diagnostic benefits of examining BMO-MRW and peripapillary retinal nerve fibre layer (pRNFL) readings acquired with Spectralis OCT to distinguish between healthy and mild glaucoma patients, comparing those readings with the standard pRNFL application. Moreover, we investigated whether using a particular combination of BMO-MRW and pRNFL parameters with a linear discriminant function (LDF) could further enhance glaucoma diagnosis. METHODS: One hundred thirty-six eyes from 136 individuals were incorporated into this observational, prospective cross-sectional study: 68 mild primary open-angle glaucoma (POAG) patients according to the Hodapp-Parrish-Anderson criteria (mean deviation between 0 and - 6 dB) and 68 healthy control subjects selected by Propensity Score Matching. MRW and pRNFL thickness around the disc (diameters: 3.5 mm, 4.1 mm, and 4.7 mm) were obtained using the BMO-MRW protocol, and pRNFL thickness at 3.5 mm was obtained with the standard glaucoma application. The group data were contrasted. One sample was chosen at random to develop the LDF (teaching set: 34 healthy subjects and 34 POAG patients) using a combination of MRW and pRNFL parameters (acquired with the BMO-MRW protocol); the other sample provided a test of how the LDF performed on an independent group (validating set: 34 healthy subjects and 34 POAG patients). The receiver operating curves (ROCs) were plotted for every measurement and contrasted with the proposed LDF. The OCT parameters with the best area under the receiver operating characteristic curve (AUC) were determined. RESULTS: Global MRW and pRNFL thicknesses were significantly thinner in the POAG group (p <  0.001). The BMO-MRW parameters showed good diagnostic accuracy; the largest AUCs reached 0.875 for the LDF and 0.879 for global RNFL thickness using the standard glaucoma application. There were no statistical differences between the AUCs calculated. CONCLUSIONS: BMO-MRW parameters show a strong capability to differentiate between mild glaucoma and control eyes. Our LDF based on the new BMO-MRW OCT protocol did not perform better than isolated parameters.

Mapping choroidal thickness in patients with type 2 diabetes.

OBJECTIVE: To determine and compare topographic features of the choroidal thickness (CT) between patients with type 2 diabetes (T2D) and age-matched healthy controls based on swept source-optical coherence tomography (SS-OCT). DESIGN: Cross-sectional study. PARTICIPANTS: 96 T2D patients and 33 healthy individuals aged above 18 years and with an axial length (AL) lower than 26 mm were included. METHODS: A macular 6 × 6 mm cube, comprising 900 200 × 200 µm cubes, was scanned with SS-OCT. The choroid was automatically segmented using the segmentation algorithm. Three-dimensional maps were created to represent the choroid. The scanned area was divided into different zones based on CT, and equivalent zones were compared between groups. RESULTS: Mean age (standard deviation) in the control group was 66.83 (7.3) years, and that of the T2D group was 67.94 (7.9) years (p = 0.48). Both groups were similar regarding AL and spherical equivalent. Overall, CT was significantly thinner in the T2D group; it was 203.78 (53.40) in healthy individuals and 169.98 (63.22) in T2D patients (p = 0.01). Outside the fovea, the mean CT was thicker in the superior hemiretina and decreased inferiorly, temporally, and nasally, with minimum thickness in the most distant points from the fovea. CONCLUSIONS: Choroidal thickness follows an ellipsoid pattern in both nondiabetic and diabetic eyes, with diabetic eyes showing thinner measurements diffusely. Understanding these differences is important for future studies aimed at understanding the pathophysiological underpinnings of diabetic retinopathy.

Reproducibility of retinal and choroidal measurements using swept-source optical coherence tomography in patients with Parkinson's disease.

PURPOSE: To assess the reproducibility of retinal and choroidal measurements in the macular and peripapillary areas using swept-source optical coherence tomography in patients with Parkinson's disease. METHODS: A total of 63 eyes of 63 patients with idiopathic Parkinson's disease were evaluated using a three-dimensional protocol of swept-source optical coherence tomography. The following layers were analyzed: full retinal thickness, retinal nerve fiber layer, ganglion cell layer, and choroid. The coefficient of variation was calculated for every measurement. RESULTS: In the macular area, the mean coefficients of variation of retinal thickness, ganglion cell layer + thickness, and choroidal thickness were 0.40%, 0.84%, and 2.09%, respectively. Regarding the peripapillary area, the mean coefficient of variation of the retinal nerve fiber layer thickness was 2.78. The inferior quadrant showed the highest reproducibility (coefficient of variation= 1.62%), whereas the superonasal sector showed the lowest reproducibility (coefficient of variation= 8.76%). CONCLUSIONS: Swept-source optical coherence tomography provides highly reproducible measurements of retinal and choroidal thickness in both the macular and peripapillary areas. The reproducibility is higher in measurements of retinal thickness versus choroidal thickness.

Comparison of visual and optical quality of monofocal versus multifocal intraocular lenses.

OBJECTIVE: To compare visual quality in patients implanted with Tecnis® monofocal (ZCB00) and multifocal (ZMB00) intraocular lenses taking into account their optical quality measured in vitro with an eye model. METHODS: In total, 122 patients participated in this study: 44 implanted with monofocal and 78 with multifocal intraocular lenses. Measurements of visual acuity and contrast sensitivity were performed. The optical quality of the intraocular lenses was evaluated in three image planes (distance, intermediate and near) using an eye model on a test bench. The metric considered was the area under the curve of the modulation transfer function. RESULTS: Optical quality at the far focus of the monofocal intraocular lens (area under the curve of the modulation transfer function = 66.97) was considerably better than that with the multifocal lens (area under the curve of the modulation transfer function = 32.54). However, no significant differences were observed between groups at the distance-corrected visual acuity. Distance-corrected near vision was better in the multifocal (0.15 ± 0.20 logMAR) than that in the monofocal group (0.43 ± 0.21 logMAR, p < 0.001), which correlated with the better optical quality at near reached by the multifocal intraocular lens (area under the curve of the modulation transfer function = 29.11) in comparison with the monofocal intraocular lens (area under the curve of the modulation transfer function = 5.0). In intermediate vision, visual acuity was 0.28 ± 0.16 logMAR (multifocal) and 0.36 ± 0.14 logMAR (monofocal) with p = 0.014, also in good agreement with the values measured in the optical quality (area under the curve of the modulation transfer function = 10.69 (multifocal) and 8.86 (monofocal)). The contrast sensitivity was similar in almost all frequencies. Pelli-Robson was slightly better in the monofocal (1.73) than in the multifocal group (1.64; p = 0.023). CONCLUSION: Patients implanted with multifocal ZMB00 achieved a distance visual acuity similar to those implanted with monofocal ZCB00, but showed significantly better intermediate and near visual acuity. A correlation was found between intraocular lenses' optical quality and patients' visual acuity. Contrast sensitivity was very similar between the multifocal and monofocal groups.

Visual cognitive impairments in children at risk of prenatal alcohol exposure.

AIM: To evaluate the relationship between visoperception and anthropometric features related to prenatal alcohol exposure. METHODS: We compared two cohorts of infants aged between 5 and 18 years. Seventy-nine children, adopted from Eastern Europe, were included in the study group. The control group was formed by age and gender matched children born in Spain. All children underwent a full ophthalmologic assessment and standardised testing of visual cognitive skills. RESULTS: Adoptees presented worse visual motor and visual perceptual outcomes in all skills compared with control subjects, with statistically significant difference in test of visual perceptual skills (TVPS) global centile (50.3 vs 66.8; P = 0.001), spatial relationships (64.6 vs 81.9; P = 0.004) and visual figure-ground (52.1 vs 74.1; P = 0.002) tasks. Face recognition was as well significantly worse in adopted children (42.4 vs 57.1; P = 0.009). Twenty-one adopted children (26.6%) had sentinel finding for foetal alcohol spectrum disorders (FASD). Main facial features related to FASD correlated with visual cognitive outcomes. Of the adopted children, those diagnosed of FASD showed incrementally worse visual perceptual and visual motor outcomes (TVPS global centile = 36.86, P = 0.001; TVAS = 10.38, P = 0.002). CONCLUSION: Children adopted from eastern Europe are at increased risk of visual perceptual disabilities, especially those with sentinel findings of foetal alcohol syndrome disorders.

Swept source optical coherence tomography to early detect multiple sclerosis disease. The use of machine learning techniques.

OBJECTIVE: To compare axonal loss in ganglion cells detected with swept-source optical coherence tomography (SS-OCT) in eyes of patients with multiple sclerosis (MS) versus healthy controls using different machine learning techniques. To analyze the capability of machine learning techniques to improve the detection of retinal nerve fiber layer (RNFL) and the complex Ganglion Cell Layer-Inner plexiform layer (GCL+) damage in patients with multiple sclerosis and to use the SS-OCT as a biomarker to early predict this disease. METHODS: Patients with relapsing-remitting MS (n = 80) and age-matched healthy controls (n = 180) were enrolled. Different protocols from the DRI SS-OCT Triton system were used to obtain the RNFL and GCL+ thicknesses in both eyes. Macular and peripapilar areas were analyzed to detect the zones with higher thickness decrease. The performance of different machine learning techniques (decision trees, multilayer perceptron and support vector machine) for identifying RNFL and GCL+ thickness loss in patients with MS were evaluated. Receiver-operating characteristic (ROC) curves were used to display the ability of the different tests to discriminate between MS and healthy eyes in our population. RESULTS: Machine learning techniques provided an excellent tool to predict MS disease using SS-OCT data. In particular, the decision trees obtained the best prediction (97.24%) using RNFL data in macular area and the area under the ROC curve was 0.995, while the wide protocol which covers an extended area between macula and papilla gave an accuracy of 95.3% with a ROC of 0.998. Moreover, it was obtained that the most significant area of the RNFL to predict MS is the macula just surrounding the fovea. On the other hand, in our study, GCL+ did not contribute to predict MS and the different machine learning techniques performed worse in this layer than in RNFL. CONCLUSIONS: Measurements of RNFL thickness obtained with SS-OCT have an excellent ability to differentiate between healthy controls and patients with MS. Thus, the use of machine learning techniques based on these measures can be a reliable tool to help in MS diagnosis.

Changes in peripapillary choroidal thickness in patients with multiple sclerosis.

PURPOSE: To study peripapillary choroidal thickness (PPCT) around the optic disc and establish zones using a new swept source optical coherence tomography (SS-OCT) device. To evaluate PPCT differences between patients with multiple sclerosis (MS) and age- and sex-matched healthy controls. METHODS: A total of 102 healthy subjects and 51 patients with MS were consecutively recruited. Healthy subjects were divided into teaching (n = 51, used to establish choroidal zones) and validating (n = 51, used to compare measurements with MS patients) populations. An optic disc 6.0 × 6.0-mm three-dimensional scan was obtained using SS-OCT Triton. A 26 × 26 cube-grid centred on the optic disc was generated automatically to measure PPCT. Four choroidal zones were established and used to compare PPCT between healthy controls and patients with MS. RESULTS: Peripapillary choroidal thickness (PPCT) was significantly thinner in patients in all concentric zones (p ≤ 0.0001): 134.02 ± 16.59 µm in MS group versus 171.56 ± 12.43 µm in the control group in zone 2; 182.23 ± 20.52 versus 219.03 ± 17.99 µm, respectively, in zone 3; and 223.52 ± 10.70 versus 259.99 ± 10.29 µm, respectively, in zone 4. The choroidal thinning in the MS group tended to decrease as we distanced from the optic nerve head. Peripapillary choroidal thickness (PPCT) had a similar pattern in controls and MS; it was thicker in the superior region, followed by temporal, nasal and inferior regions. CONCLUSION: Patients with MS showed peripapillary choroidal thinning when compared with healthy subjects in all zones around the optic disc. Peripapillary choroidal tissue shows a concentric pattern, increasing in thickness when increasing the distance from the optic nerve. The new SS-OCT could be useful for evaluating choroidal thinning in clinical practice.

Ability of swept source OCT to detect retinal changes in patients with bipolar disorder.

PURPOSE: To evaluate the ability of swept source optical coherence tomography (SS-OCT) to detect retinal changes in patients with bipolar disorder (BD). METHODS: Twenty-three patients with BD and 23 controls underwent retinal evaluation using SS deep range imaging (DRI) Triton OCT. Full retinal thickness, the ganglion cell layer (GCL), the retinal nerve fiber layer (RNFL), and choroidal thickness were evaluated with automated segmentation software. RESULTS: Patients with BD were shown to have significant thinning of the macular full retinal thickness in the center (p = 0.049), inner temporal (p = 0.045), inner nasal (p = 0.016), and inner inferior (p = 0.016) of the ETDRS areas. The macular GCL layer was reduced in patients compared with controls (average, p = 0.002; superior, p = 0.009; superonasal, p = 0.009; inferonasal, p = 0.003; and inferior, p = 0.009). Peripapillary reduction of full retinal thickness (average, p < 0.001; superotemporal, p < 0.001; superonasal, p = 0.003; nasal, p = 0.005; and inferotemporal, p = 0.033), GCL (nasal, p = 0.025), and RNFL thickness (average, p = 0.002; superotemporal, p < 0.001; and superonasal, p = 0.045) was observed in patients compared with controls. No significant differences were observed in choroidal thickness measurements. CONCLUSIONS: BD patients were shown to have quantifiable thinning of full retinal thickness and the GCL in the macular area, as well as a peripapillary reduction of the RNFL and GCL thickness. The analysis of the retinal sublayers with SS-OCT may be a useful indicator to show degeneration and monitor disease progression in bipolar disorder.