SOCT Copernicus Research Articles

Detection of subretinal and intraretinal fluids in optopol SD‐OCT using transfer learning

Aims/Purpose: The detection of subretinal fluid (SRF) and intraretinal fluid (IRF) in optical coherence tomography (OCT) images plays a crucial role in the diagnosis and treatment of certain eye diseases. In this study, we investigated the performance of a Transfer Learning artificial intelligence (AI) technique, which we used to perform the model adaptation from the domain of Heidelberg OCT images to Optopol devices.Methods: A data set of 133 Optopol OCT images. 69 images indicating subretinal or intraretinal fluid and 64 fluid‐free images, were analysed. The AI algorithm that was initially trained on OCT images from Heidelberg device was fine‐tuned to perform the biomarker segmentation in Optopol (Revo NX, SOCT Copernicus REVO, REVO FC) OCT images. Manual assessments by the medical experts were used to evaluate the algorithm's performance.Results: Our findings demonstrate the promising performance of the domain‐adapted model. in detecting SRF and IRF, when initially trained on OCT images from a different device. The algorithm achieved an accuracy of 80% while classifying the presence versus absence of the fluids on the balanced test data set.Conclusions: The study demonstrates a successful application of a transfer learning technique for detection of subretinal and intraretinal fluids in OCT images acquired with the Optopol devices, indicating its potential for enhancing eye diagnostics. Further studies utilizing larger data sets, further biomarkers and diverse OCT devices are warranted to validate the algorithm's robustness and generalizability.

Study of interactions between CFH gene polymorphism and retinal pigment epithelium phenotype in age-related macular degeneration

Annotation. AMD (age-related macular degeneration) is one of the leading causes of blindness in the world, associated with the formation of extracellular deposits called drusen in the macula, i.e. in the central part of the retina. These drusen contain cellular debris and proteins, including components of the complement system, such as the regulator CFH (complement factor H). Complement dysregulation is believed to play a major role in the development of AMD. CFH acts through its ability to recognize polyanionic structures (eg, sulfated GAGs (glycosaminoglycans)) found in host tissues, and thus CFH inactivates any complement system (C3b) that is deposited. Importantly, the common CFH (Y402H) polymorphism was strongly associated with an increased risk of AMD. Recent studies have shown that the disease-associated allotype 402H interacts more poorly (compared to 402Y) with binding sites in the macula (eg, Bruch's membrane), where GAGs (glycosaminoglycans), heparan sulfate, and dermatan sulfate play a major role in mediating the interaction with CFH. Decreased binding of the 402H allotype may lead to complement dysregulation, leading to chronic local inflammation that may contribute to drusen accumulation and thus the initiation, development, and progression of AMD. That is why the goal of our study was to highlight the effect of the rs1061170 polymorphism of the CFH gene on the occurrence and development of age-related macular degeneration and to clarify the intensity of this pathological effect. The study group consisted of 291 people suffering from AMD (89 – with the “dry” form, 97 – with the “wet” form), the comparison group – 105 people without a history of ophthalmic pathology of the corresponding age. Optical coherence tomography (SOCT Copernicus “Optopol”) of the macular area of the retina was used in the study. We used the parameter ILM-RPE (internal limiting membrane-retinal pigmented epithelium). DNA was isolated from the biological material obtained by the buccal scraping method using the Bio-Rad Chelex ® 100 kit. Polymerase chain reaction was used to detect the rs1061170 polymorphism of the CFH gene. Statistical processing of the obtained results was carried out using Statistica 10 (StatSoft, Inc., USA) and SPSS 23.0 programs. The following were used: Hardy-Weinberg equilibrium (Hardy–Weinberg); Kruskal-Wallis test ANOVA by Ranks and Friedman ANOVA and Kendall Coeff. of Concordance; H-criterion; indicators of the odds ratio (OR; Odds Ratio – OR) and 95% probable interval (±95% CI; Confidence limit for means Interval – CI); used the method of analysis of operating characteristic curves (ROC – Receiver Operating Characteristic curve analysis); used special formulas using 2x2 tables. Our results confirm the high prognostic significance of the rs1061170 polymorphism of the CFH gene on the development and progression of AMD in the Ukrainian population. Indicators of specificity and sensitivity of SNP genotypes are ambiguous.

Применение препарата «Визкью» в лечении экссудативной формы вмд на примере клинического случая

Purpose. To evaluate the effectiveness of treating a patient with exudative form of age-related macular degeneration (AMD) by intravitreal injection of the medicine “Vizk'yu”. Material and methods. The results of the injection of medicine “Vizk'yu” were analyzed. To assess the effectiveness of the medicine, the patient underwent visometry and optical coherence tomography (OCT) using the Optopol SOCT Copernicus device. Results. Patient R., male, 61 years old, diagnosed with exudative AMD in the right eye received a treatment in the form of an intravitreal injection of “Lucentis” into the right eye from December 12, 2020, the initial tomography data are shown in fig. 1. Patient received three loading injections, then the treatment was continued in a proactive mode. From December 2020 to January 2022 he received 7 injections of “Lucentis”. In the course of treatment, an insufficient effect in the suppression of neovascularization was revealed (November 23, 2021), which was expressed in the presence of subretinal fluid and intraretinal fluid, which is shown in the results of OCT in fig. 2. In connection with this, it was decided to transfer the patient from “Lucentis” therapy to “Vizk'yu” therapy. “Vizk'yu” therapy was started on January 11, 2022 with monthly boot injections. So far, 3 injections have been made. After changing the therapy, there is a positive trend (fig. 4–5), which is expressed in a significant decrease in the amount of intraretinal and subretinal fluids, as well as in the stabilization of visual acuity (fig. 3). Conclusion. The use of “Vizk'yu” on a patient with exudative form of AMD led to an improvement in the morphological state of the retina, to resorption of subretinal and intraretinal fluids, contributed to a persistent decrease in the retinal thickness in fovea, and also stabilized visual acuity. Keywords: “Vizk'yu”, “Lucentis”, age-related macular degeneration, macular edema, OCT.

Morphometric parameters of the optic disc and peripapillary retina in children in cases of congenital pathology

Purpose: to study the nature of changes in morphological parameters of the children’s optic disc and peripapillary retina in cases of congenital pathology.Material and methods. 45 children aged 5–17 (the median age was 9.5 years) with congenital pathology of the optic disc (optic disc drusen — 15 eyes, myelinated nerve fibers — 10, optic disc coloboma — 10 and hypoplasia — 10 eyes) were tested for morphological parameters of the optic disc — the disc area, the area and volume of the neuroretinal rim and the thickness of retinal nerve fiber layer (RNFL) — using optical coherence tomography (OCT, SOCT Copernicus HR). The control group included 15 healthy children (15 eyes) of the same age group.Results. The analysis of the mean values of morphometric parameters of the optic disc and peripapillary retina revealed statistically significant changes of morphometric indicators of the optic disc compared to the norm and their specificity for each type of congenital pathology were identified. Children with optic disc drusen showed an increased optic disc area, increased area and volume of the neuroretinal rim, and thicker RNFL. In cases of myelinated nerve fibers, the area of the optic disc and the area and volume of the neuroretinal rim were increased, too: however, the increased thickness of RNFL was observed in only half of the cases. All children with optic disc coloboma showed a reliable increase of optic disc area, reliable drop in neuroretinal rim area and volume, and statistically insignificant increase of RNFL thickness.Conclusion. Morphometric features of the optic disc revealed for individual pathologies (myelinated fibers, drusen, coloboma, hypoplasia) revealed by OCT allow one to predict the development of clinical and functional disturbances in children with congenital optic nerve abnormalities.

Normal Reference Ranges of Optical Coherence Tomography Parameters in Children.

To measure the macular thickness, macular volume and peripapillary retinal nerve fiber layer (RNFL) in healthy Caucasian chil-dren using spectral domain optical coherence tomography (SDOCT) and analyze the correlation of these values with age, refraction, and biometric measurements. In this cross-sectional study, we recruited 270 healthy children (150 female and 120 male) aged 6 to 17 years with no ocular abnormalities. All children underwent a detailed eye examination. The measurements were obtained using a SDOCT device (SOCT Copernicus REVO). Main outcome measures were macular thickness, macular volume and RNFL thickness. Their correlations with age, refractive error, anterior chamber depth (ACD) and axial length (AL) was analyzed. Right eyes of all subjects were selected for analysis. In this study group (mean age 10.70±2.82 years), the average peripapillary RNFL thickness was 117.11±9.15 μm, the central macular thickness was 232.10±15.81 μm, the average macular thickness was 286.70±9.82 μm, and the average macular volume was 8.01±0.28 mm³. The average values for the biometric data were: axial length - 23.16±0.94 mm, anterior chamber depth - 3.64±0.26 mm, the spherical equivalent (SE) value - +0.81±0.58 diopter. Central macular thickness, inner macular thickness (superior, inferior, nasal, temporal quadrants) values, total macular thickness and macular volume were significantly higher in males than in females. We found a positive correlation between central macular thickness, inner nasal macular thickness, outer inferior macular thickness values, and age. Also, we found a significant correlation between the average macular thickness values and the average macular volume values (p<0.0001). RNFL measurements did not correlate with age (p=0.199). Almost all macular parameters were consistently positively cor-related with SE. A significant correlation was also found between the central macular thickness, inner inferior macular thickness, inner nasal macular thickness and the ACD. We found a significant correlation between the average macular thickness, macular volume, inner superior macular thickness, outer macular thickness (superior, inferior, nasal, temporal quadrants) values and the AL. This study found normal reference ranges for RNFL and macular parameters measured by SOCT Copernicus REVO in healthy Caucasian children aged 6-17 years. This normative values could be very useful in early diagnosing and monitoring of optic neuropathy, glaucoma and macular diseases in childhood.

Optical coherence tomography in preclinical diagnosis of optic nerve disk changes after chemotherapy in children with retinoblastoma

Purpose . Using optical coherence tomography (OCT), determine the preclinical changes in optic nerve head (ONH) after chemotherapy in children with retinoblastoma (RB). Material and methods . 38 patients (76 eyes) were examined and treated: 15 girls, 23 boys with RB averagely aged 21.0 ± 1.5 months. Of these, 58 affected eyes before treatment belonged to groups А (3), В (16), С (33), D (3), and Е (3). All tumor nodes were located on the fundus outside the optic disk. The examination of these eyes was carried out on an optical coherent tomograph SOCT Copernicus 4.2 (Poland). The 58 eyes were first tested before treatment, then after 3 or 4 courses of systemic chemotherapy (CT), once again after 6 courses of systemic CT and 1–3 courses of superselective intraarterial CT and 4–9 courses of intravitreal CT. 15 healthy children (30 eyes) of the corresponding age were examined as a control. Results . After 3 courses of systemic CT, OCT determined optic neuropathy with edema in 46.6 %. Morphometric data included parapapillary retinal cystic cavities, elevation of the contour of the optic disc towards the vitreous, increased rim volume (to 0.87 ± 0.12 mm 3 ) and average thickness of the nerve fiber layer increased to 0.39 ± 0.06 mm (p &lt; 0.01). After combined chemotherapy we revealed the thinning of the peripapillary choroid (to 80.0 ± 3.2 μm) with no retinal edema in 34.5 %, a reduction of rim volume to 0.34 ± 0.2 mm 3 and the layer of nerve fibers to 0.02 ± 0.01 mm (p &lt; 0.01). These changes are evidences of optic nerve disc atrophy. Conclusion . OCT is an informative method of examining the optic disc in children with RB at different stages of treatment, which identifies signs of edema and symptoms of atrophy more often (respectively, by 15.6 % and 17.3 %). Preclinical diagnostics of optic disc pathology with the help of OCT allows predicting visual functions in children with RB at its early stages and developing a differentiated approach to the choice of RB treatment.

Macular Morphology in Patients with Retinopathy of Prematurity

Purpose: To investigate macular morphology by spectral domain optical coherence tomography (SDOCT) in children with history of the retinopathy of prematurity (ROP). Materials and methods: In this cross-sectional study we included 35 eyes of 18 patients, aged 4 to 8 years, with history of ROP. Twenty-one eyes had received treatment for type 1 pre-threshold ROP. The others showed spontaneous regression of the disease. A 7 × 7-mm retinal area was sampled using a 3-dimensional scanning protocol with high-resolution spectral domain optical coherence tomography (SOCT Copernicus REVO). The central foveal thickness, mean macular thickness, macular volume and foveal depression were measured. The macular anatomy and the foveal contour were examined. Results: The mean birth weight was 1338.29 ± 324.05 grams. Mean gestational age at birth was 29.37 ± 2.07 weeks. Twenty-one eyes were treated with laser or cryotherapy. All of them showed regression of the disease. The mean best corrected visual acuity was 20/28. The average central foveal thickness was 262.26 ± 37.39, with 68.57% of preterm > 240 μm and 22.86% > 220 μm. In all eyes, the foveal contour is abnormal. A foveal depression was absent in 25 eyes (71%). Conclusion: In the majority of children with a history of ROP, we found changes in macular morphology, including retention of inner retinal layers and absent foveal depression. In our study foveal hypoplasia was associated with good functional outcome.

ИЗМЕНЕНИЯ УГЛОВЫХ ХАРАКТЕРИСТИК ДИСКА ЗРИТЕЛЬНОГО НЕРВА У ПАЦИЕНТОВ С ПРОГРЕССИРУЮЩЕЙ МИОПИЕЙ ПО ДАННЫМ СПЕКТРАЛЬНОЙ ОПТИЧЕСКОЙ КОГЕРЕНТНОЙ ТОМОГРАФИИ

В статье представлены данные об изменениях угловых характеристик диска зрительного нерва (ДЗН) при прогрессирующей миопии. Под наблюдением находились пациенты, которые были разделены на группы: I-я группа − 25 пациентов (50 глаз) с медленными темпами прогрессирования миопии (до 1.0 дптр. за год); II-я группа − 25 пациентов (50 глаз) с быстрыми темпами прогрессирования миопии (более 1.0 дптр. за год); III-я группа − 20 здоровых детей (40 глаз) с эмметропией. Морфологический анализ ДЗН и перипапиллярной области сетчатки проведен методом спектральной оптической когерентной томографии (СОКТ) на аппарате «Soct Copernicus Optopol» по стандартному протоколу. Угловые характеристики ДЗН определяли по величине угла между линиями, проведенными от края ДЗН к наиболее глубокой точке физиологической экскавации ДЗН на всех сканограммах, полученных в режиме «Asterisk scanning program» с последующим вычислением средней величины угла. Статистическую обработку полученных данных проводили с использованием дисперсионного анализа и критерия Ньюмена–Кейлса.В результате проведенных исследований установлено, что на фоне отсутствия достоверных изменений показателей стандартной морфометрии ДЗН выявлены изменения угловых характеристик, а именно: уменьшение угловой характеристики ДЗН у детей с быстрым прогрессированием миопии до 127°±2,8, в то время как при эмметропии и при медленно прогрессирующей миопии этот показатель составляет 152°±2,9 и 150°±3,1 (р&lt;0,05), что может свидетельствовать о склонности данной категории пациентов к формированию деформаций ДЗН.

Analysis of Ganglion Cell Complex and Retinal Nerve Fiber Layer Thickness in Glaucoma Diagnosis.

The aim was to compare retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thicknesses in patients with primary open angle glaucoma (POAG), ocular hypertension (OH) and healthy subjects, and to investigate the role of GCC parameters in glaucoma diagnosis. Eighty-one patients were divided into four groups according to Hodapp-Parrish-Anderson classification: 26 OH, 22 early POAG, 10 moderate to advanced POAG, and 23 healthy subjects. All patients underwent RNFL and GCC thickness measurement using SOCT Copernicus HR. All RNFL and GCC parameters were significantly lower in POAG than in OH and healthy subjects, especially Average RNFL, RNFL Superior and Inferior, GCC Average, and GGC Inferior. Of all RNFL parameters, the highest area under the receiver operating characteristic curve (AUC) was recorded for Average RNFL, 0.906. GCC Average, and GCC Superior and Inferior had the overall highest AUCs (0.957, 0.955 and 0.946, respectively) with 100% specificity. The RNFL Average and Inferior and GCC Average, Superior and Inferior were identified as the main predictors for development of glaucoma (p=0.015 and p=0.014 vs. p=0.002, p=0.002 and p=0.003, respectively). In conclusion, GCC parameters showed a slightly better glaucoma discriminating ability and were found to be better predictors for development of glaucoma as compared with RNFL.

Automatic method of analysis of OCT images in assessing the severity degree of glaucoma and the visual field loss

IntroductionIn many practical aspects of ophthalmology, it is necessary to assess the severity degree of glaucoma in cases where, for various reasons, it is impossible to perform a visual field test - static perimetry. These are cases in which the visual field test result is not reliable, e.g. advanced AMD (Age-related Macular Degeneration). In these cases, there is a need to determine the severity of glaucoma, mainly on the basis of optic nerve head (ONH) and retinal nerve fibre layer (RNFL) structure. OCT is one of the diagnostic methods capable of analysing changes in both, ONH and RNFL in glaucoma.Material and methodOCT images of the eye fundus of 55 patients (110 eyes) were obtained from the SOCT Copernicus (Optopol Tech. SA, Zawiercie, Poland). The authors proposed a new method for automatic determination of the RNFL (retinal nerve fibre layer) and other parameters using: mathematical morphology and profiled segmentation based on morphometric information of the eye fundus. A quantitative ratio of the quality of the optic disk and RNFL – BGA (biomorphological glaucoma advancement) was also proposed. The obtained results were compared with the results obtained from a static perimeter.ResultsCorrelations between the known parameters of the optic disk as well as those suggested by the authors and the results obtained from static perimetry were calculated. The result of correlation with the static perimetry was 0.78 for the existing methods of image analysis and 0.86 for the proposed method. Practical usefulness of the proposed ratio BGA and the impact of the three most important features on the result were assessed. The following results of correlation for the three proposed classes were obtained: cup/disk diameter 0.84, disk diameter 0.97 and the RNFL 1.0. Thus, analysis of the supposed visual field result in the case of glaucoma is possible based only on OCT images of the eye fundus.ConclusionsThe calculations and analyses performed with the proposed algorithm and BGA ratio confirm that it is possible to calculate supposed mean defect (MD) of the visual field test based on OCT images of the eye fundus.

Automatic analysis of selected choroidal diseases in OCT images of the eye fundus

IntroductionThis paper describes a method for automatic analysis of the choroid in OCT images of the eye fundus in ophthalmology. The problem of vascular lesions occurs e.g. in a large population of patients having diabetes or macular degeneration. Their correct diagnosis and quantitative assessment of the treatment progress are a critical part of the eye fundus diagnosis.Material and methodThe study analysed about 1’000 OCT images acquired using SOCT Copernicus (Optopol Tech. SA, Zawiercie, Poland). The proposed algorithm for image analysis enabled to analyse the texture of the choroid portion located beneath the RPE (Retinal Pigment Epithelium) layer. The analysis was performed using the profiled algorithm based on morphological analysis and texture analysis and a classifier in the form of decision trees.ResultsThe location of the centres of gravity of individual objects present in the image beneath the RPE layer proved to be important in the evaluation of different types of images. In addition, the value of the standard deviation and the number of objects in a scene were equally important. These features enabled classification of three different forms of the choroid that were related to retinal pathology: diabetic edema (the classification gave accuracy ACC1 = 0.73), ischemia of the inner retinal layers (ACC2 = 0.83) and scarring fibro vascular tissue (ACC3 = 0.69). For the cut decision tree the results were as follows: ACC1 = 0.76, ACC2 = 0.81, ACC3 = 0.68.ConclusionsThe created decision tree enabled to obtain satisfactory results of the classification of three types of choroidal imaging. In addition, it was shown that for the assumed characteristics and the developed classifier, the location of B-scan does not significantly affect the results. The image analysis method for texture analysis presented in the paper confirmed its usefulness in choroid imaging. Currently the application is further studied in the Clinical Department of Ophthalmology in the District Railway Hospital in Katowice, Medical University of Silesia, Poland.

Methods of measuring the iridocorneal angle in tomographic images of the anterior segment of the eye

IntroductionThis paper presents the problem of automatic measurement of the iridocorneal angle in tomographic images of the anterior segment of the eye. It includes the results of the comparison of well-known methods for measuring the iridocorneal angle with new methods, proposed in this paper. All these methods concern tomographic image analysis and processing.Material and methodIn total, approximately 100’000 tomographic images (from about 6’000 patients) were analysed. They were obtained using two devices: SOCT Copernicus (Optopol Tech. SA, Zawiercie, Poland) and Visante OCT (Carl Zeiss Meditec, Inc, Dublin, California, USA). The patients, aged 12 to 78 years with varying degrees of the iridocorneal angle pathology, were from the region of Silesia, Poland. The images were in DICOM or RAW formats and analysed in the software developed by the authors for the purposes of this study.ResultsThe results indicate that the measurement method proposed by the authors, which is based on the calculation of the minimum distance between the iris and the cornea in the adopted area, is the most accurate. For this method sensitivity was 0.88, specificity 0.89 and the area under the Receiver Operating Characteristic curve (AUC) was 0.88. The other known methods for measuring the iridocorneal angle gave worse results, that is, for example, for the measurement of the distance between the iris and the cornea AUC = 0.87, sensitivity = 0.86 and specificity = 0.71. For another well-known method of measuring the iridocorneal angle AUC = 0.77, sensitivity = 0.82 and specificity = 0.61.ConclusionsThe study proved that the proposed method of measuring the minimum distance between the iris and the cornea within the adopted area is the most effective in the classification of the iridocorneal angle in patients with a high degree of pathology of all the compared measurement methods based on tomographic images. However, it requires fully automated measurement.

Morphometrical indices in acquired myopia

AbstractPurpose On an etiology myopia can be congenital and acquired (school myopia), and on character of development – stable and progressing. According to experimental works (Ai L, Li J, Guan H, Wildsoet CF,2009, Nickla DL, Wildsoet CF, Troilo D., 2002) it is known, that the thickness of a retina varies at eyeball growth, and also at defocus change. The probability of myopia growth in each patient remains difficult to predict. The purpose was to reveal differences in patients with acquired myopia and divide them on studied indicesMethods A child of 7‐15 years old (53) with myopia were observed, a criterion of inclusion in research was acquired myopia. Parameters which were studied: visual acuity, refraction, axis length of an eye, accommodation reserves, intraocular pressure, retina layer thickness and peripapillary fiber layer thickness, optic nerve disk indices by optical coherent tomography under standard protocols by SOCT Copernicus, Optopol Technology Sp.z o.o., PolandResults Optimum points of division of acquired myopia on stable and progressing were established by ROC analysis. The discriminate analysis with high reliability has shown, that the progressing form of myopia will be observed in children with average thickness in a zone 3mm more than 246,3mk , with a refraction more than 4,5 dptr and axes more than 25,3mm (Р=0,0001). Fisher's discriminating functions are defined and the equations for definition of the stable and progressing forms of acquired myopia are offered. Effect of classification is 80,3%.Conclusion Results have allowed to offer model of classification for the stable and progressing forms of myopia on morfometric indices, axis length and refraction in patients with acquired myopia

Structural Grading of Foveal Hypoplasia Using Spectral-Domain Optical Coherence Tomography: A Predictor of Visual Acuity?

To characterize and grade the spectrum of foveal hypoplasia based on different stages of arrested development of the fovea. Grading was performed using morphologic findings obtained by ultra high-resolution spectral-domain optical coherence tomography. Best-corrected visual acuity (BCVA) was calculated for different grades. Observational case series. Sixty-nine patients with foveal hypoplasia (albinism, n = 34; PAX6 mutations, n = 10; isolated cases, n = 14; achromatopsia, n = 11) and 65 control subjects were examined. A 7×7-mm retinal area was sampled using a 3-dimensional scanning protocol (743×75, A scans×B scans) with ultra high-resolution spectral-domain optical coherence tomography (SOCT Copernicus HR; 3-μm axial resolution). Gross morphologic abnormalities were documented. B-scans at the fovea were segmented using a longitudinal reflectivity profile. Logarithm of the minimum angle of resolution BCVA was obtained. Grading was based on presence or absence of foveal pit and widening of the outer nuclear layer (ONL) and outer segment (OS) at the fovea. Quantitative measurements were obtained for comparing atypical foveal hypoplasia in achromatopsia. Best-corrected visual acuity was compared with the grade of foveal hypoplasia. Four grades of foveal hypoplasia were distinguished: grade 1, shallow foveal pit, presence of ONL widening, presence of OS lengthening; grade 2, grade 1 but absence of foveal pit; grade 3, grade 2 but absence of OS lengthening; grade 4, grade 3 but absence of ONL widening. There was significant difference in visual acuity (VA) associated with each grade (P<0.0001). Grade 1 was associated with the best VA (median VA, 0.2), whereas grades 2, 3, and 4 were associated with progressively poorer VA with a median VA of 0.44, 0.60, and 0.78, respectively. The atypical features seen with foveal hypoplasia associated with achromatopsia were characterized by decreased retinal and ONL thickness and deeper foveal depth. A structural grading system for foveal hypoplasia was developed based on the stage at which foveal development was arrested, which helps to provide a prognostic indicator for VA and is applicable in a range of disorders associated with foveal hypoplasia. Atypical foveal hypoplasia in achromatopsia shows different characteristics. The author(s) have no proprietary or commercial interest in any materials discussed in this article.

OCT features of the optic disk parameters and peripapillary nervous fibres layer thickness in children with acquired myopia

Abstract Purpose To reveal morphological and structural peculiarities of retinal nerve fiber layer thickness (RNFLT) and optic nerve parameters in schoolchildren with acquired myopia in dependence of myopia degree. Methods 135 children (270 eyes) of 10‐14 y.o. with bilateral light (86 eyes), moderate (50) and high degree of myopia (42) as well as control group of healthy children (40) were observed. Morphostructural indices (PRNFLTh) in four segments (nasal, temporal, superior, and inferior) and optic disk parameters were investigated by optical coherent tomography SOCT Copernicus, OPTOPOL Tech.Sp.z o.o. applying standard protocols – Retina analysis and Disk analysis. Evaluation of data and comparisons in groups were performed with the help of STATISTICA for Windows 98, a Newman‐Kales criterion was applied. Results Significantly less (p=0,03) peripapillary RNFLT values were found in nasal segments in children with the high degree of myopia as compared to children in control group and with the light degree of myopia. We founded that it depended on Rim Area values. Disk Area (2,08 – 2,16) mm2 was found in 82,7% and above 3,0 mm2 in 17,3% of myopic patients. Disk Area 2,07 ‐ 4,25 mm2 was revealed in myopic patients and 2,08 – 3,11 mm2 in control group. Cup Area was 0,23‐0,54 mm 2 in myopic and 0,38‐1,13 mm2 in healthy children Rim Area 1,2‐3,2 mm2 in myopic and 1,66 – 2,63 mm2 in control group. Cup/Disk ratio 0,19‐1,18 was established in myopic and 0,19 – 1,18 in control group. Conclusion Axial myopia is often accompanied with cone near the optic disk. It is suggested that disk parameters such as – Disk Area and Rim Area can be identified as parameters which can be considered as the signs of myopia progression.

Macular Thickness Measurements in Healthy Eyes Using Six Different Optical Coherence Tomography Instruments

To compare central retinal thickness (CRT) measurements in healthy eyes by different commercially available OCT instruments and to compare the intersession reproducibility of such measurements. Six different OCT instruments (Stratus OCT [Carl Zeiss Meditec, Inc. Dublin, CA], SOCT Copernicus [Reichert/Optopol Technology, Inc., Depew, NY], Spectral OCT/SLO [Opko/OTI, Inc., Miami, FL], RTVue-100 [Optovue Corp., Fremont, CA], Spectralis HRA+OCT [Heidelberg Engineering, Inc., Heidelberg, Germany], and Cirrus HD-OCT [Carl Zeiss Meditec, Inc.]) were used to assess CRT in both eyes of healthy subjects. Measurements were performed in two different sessions on the same day with each of the systems. From these measurements, the mean CRT was calculated. For the assessment of the intersession reproducibility of the instruments, we calculated the coefficient of the variation of test-retest variation. Twenty healthy subjects were included in the study. Compared with the Stratus OCT all spectral OCT instruments showed significantly higher CRTs. The Spectralis HRA+OCT and Cirrus HD-OCT showed similar CRT values but significantly higher values than did all other instruments. The coefficients of variation for repeated measurements was 3.33% for the Stratus OCT, 0.46% for the Spectralis HRA+OCT, 3.09% for the Cirrus HD-OCT, 2.23% for the OCT/SLO, 2.77% for the RTVue-100 OCT, and for the SOCT 3.5%, respectively. discussion. The six OCT systems provided different results for CRT. The measurements with the Stratus OCT showed the lowest thicknesses, whereas those with the Cirrus HD-OCT and Spectralis HRA+OCT yielded the highest ones. These discrepancies can be explained by the differences in the retinal segmentation algorithms used by the various OCT systems. Whereas the Spectralis HRA+OCT and Cirrus HD-OCT include the RPE layer in the retinal segmentation, the other instruments do not. The data imply that the different OCT systems cannot be used interchangeably for the measurement of macular thickness.