Slawomir Teper

Anterior segment imaging: Fourier-domain optical coherence tomography versus time-domain optical coherence tomography.

PURPOSE: To compare anterior segment measurements and morphology of 2 optical coherence tomography (OCT) systems. SETTING: Department of Ophthalmology, District Railway Hospital, and the Nursing Department and Social Medical Issues, Health Care Division, Silesian Medical University, Katowice, Poland. METHODS: In normal eyes and in eyes with corneal and trabecular–iris angle disorders, the central corneal thickness (CCT), trabecular–iris angle, and angle‐opening distance at the nasal and temporal angles were measured 3 times during 1 visit using the Visante time‐domain OCT system and the RTVue‐100 Fourier‐domain corneal anterior module OCT system. Anterior segment morphology was assessed and compared. RESULTS: Fifty‐four eyes were evaluated. The mean values (±SD) by time‐domain OCT and Fourier‐domain OCT were, respectively, automatic CCT, 535 ± 33.07 μm and 538 ± 31.82 μm; manual CCT, 545 ± 30.91 μm and 542 ± 30.57 μm; nasal trabecular–iris angle, 34.7 ± 9.5 degrees and 35.2 ± 8.9 degrees; temporal trabecular–iris angle, 35.3 ± 8.5 degrees and 35.5 ± 9 degrees; nasal angle‐opening distance, 435 ± 95 μm and 444 ± 98 μm; and temporal angle‐opening distance, 443 ± 103 μm and 452 ± 99 μm. There was no significant difference between mean values, and they were highly correlated. On morphologic analysis, time‐domain OCT had lower resolution; however, all anterior chamber structures were visible on 1 image. Fourier‐domain OCT provided precise information about small areas of the anterior chamber. CONCLUSION: Fourier‐domain OCT provided accurate anterior eye segment measurements that agreed with those obtained with time‐domain OCT.

Fully automatic algorithm for the analysis of vessels in the angiographic image of the eye fundus

BackgroundThe available scientific literature contains descriptions of manual, semi-automated and automated methods for analysing angiographic images. The presented algorithms segment vessels calculating their tortuosity or number in a given area. We describe a statistical analysis of the inclination of the vessels in the fundus as related to their distance from the center of the optic disc.MethodsThe paper presents an automated method for analysing vessels which are found in angiographic images of the eye using a Matlab implemented algorithm. It performs filtration and convolution operations with suggested masks. The result is an image containing information on the location of vessels and their inclination angle in relation to the center of the optic disc. This is a new approach to the analysis of vessels whose usefulness has been confirmed in the diagnosis of hypertension.ResultsThe proposed algorithm analyzed and processed the images of the eye fundus using a classifier in the form of decision trees. It enabled the proper classification of healthy patients and those with hypertension. The result is a very good separation of healthy subjects from the hypertensive ones: sensitivity - 83%, specificity - 100%, accuracy - 96%. This confirms a practical usefulness of the proposed method.ConclusionsThis paper presents an algorithm for the automatic analysis of morphological parameters of the fundus vessels. Such an analysis is performed during fluorescein angiography of the eye. The presented algorithm automatically calculates the global statistical features connected with both tortuosity of vessels and their total area or their number.

Optical coherence angiography: A review.

Background: Retinal vascular diseases are one of the most common causes of blindness in the developed world. Optical Coherence Tomography Angiography (OCT-A) is a new noninvasive method that uses several algorithms to detect blood movement. This enables the creation of high-resolution vascular images with contrast depicting motionless tissue. Methods: This review presents the results of articles relevant to age-related macular degeneration (AMD), diabetic retinopathy (DR), and OCT-A. The OCT-A technique can successfully be used in the diagnosis of neovascularization, retinal vein occlusion (RVO) and retinal artery occlusion (RAO), vessel abnormalities and even anterior segment neovascularization. OCT-A can also be applied to compute data such as vessel density, and flow index in both superficial and deep plexuses. Results: Many studies have compared fluorescein angiography with OCT-A. Other studies have reported differences in vascular density in AMD patients and have compared them with people having healthy eyes. Although OCT-A offers rapid picture acquisition, high repeatability and resolution, it also has many drawbacks. The most common are: motion artifacts, projections from overlying vessels and limited field of view. An interesting new application is the possibility to assess changes during antivascular endothelial growth factor (anti-VEGF) therapy. Another function of OCT-A is the possible application in the study of choriocapillaries in many fields of ocular pathology. Conclusion: OCT-A is a new promising method that allows the visualization of the retinal vascular network and the counting of blood flow parameters. This technique provides reliable images useful in clinical routines.

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.

Phenotype-genotype correlation in patients with Schnyder corneal dystrophy.

Purpose: The aim of this study was to analyze the corneal morphology features and define mutations in the UbiA prenyltransferase domain–containing 1 (UBIAD1) gene in patients with Schnyder corneal dystrophy from a Polish population. Methods: Five affected and 15 unaffected members originating from 3 families with Schnyder corneal dystrophy were included in the study. Phenotype analysis consisted of visual acuity, slit-lamp biomicroscopy with photography, time domain optical coherence tomography, spectral domain optical coherence tomography, and confocal microscopy. Three patients underwent a penetrating keratoplasty. Corneal buttons obtained from the penetrating keratoplasty were processed for light microscopy. Results: A novel mutation I245N of the UBIAD1 gene was revealed in 1 proband and associated with the phenotype without central corneal opacities. The analysis of the other patients showed the N102S mutation. In vivo corneal morphology analysis using optical coherence tomography and confocal microscopy confirmed the presence of multiple crystalline corneal deposits in all affected corneas. The histological examination revealed multiple empty widenings of the corneal lamellae that could represent lipids removed from the specimen. Conclusions: N102S may also be a mutation hotspot in the Polish population, as in other previously reported populations. Corneal crystals formed a characteristic pattern on optical coherence tomography scans.

A69S and R38X ARMS2 and Y402H CFH gene polymorphisms as risk factors for neovascular age-related macular degeneration in Poland - a brief report.

Summary Background The wet form of age-related macular degeneration (ARMD) is a leading cause of irreversible blindness in Caucasians. Our purpose was to assess influence of gene polymorphisms A69S (rs10490924) and R38X (rs2736911) ARMS2 and Y402 (rs1061170) CFH on wet ARMD risk in a Polish population. Material/Methods 130 unrelated patients (90 with wet ARMD and 40 controls) took part in the study. Dry blood was used for DNA isolation. PCR amplification and gene sequencing were performed. In subjects with R38X and A69S, SNP gene cloning was used to exclude the possible combined variant. Results Homozygous Y402H and A69S conferred a significance risk of wet ARMD in Poland: Y402H odds ratio (OR) was 5.57 (95% confidence interval: 1.58–19.6), p=0.002; and A69S OR was 7.72 (95% confidence interval: 1.73–34.36), p=0.001. R38X is probably more common in healthy subjects: OR was 0.45 (95% confidence interval: 0.19–1.05), p=0.053. Conclusions The etiologic role in ARMD of A69S ARMS2 and Y402H CFH gene variants were confirmed in a Polish population for the first time. R38X variant of ARMS2 seems to be protective from wet ARMD.

Photodynamic therapy in VEGF inhibition non-responders—Pharmacogenetic study in age-related macular degeneration assessed with swept-source optical coherence tomography

BACKGROUND Treatment of neovascular age-related macular degeneration (nAMD) remains a major challenge in ophthalmology. It is essential to determine which of VEGF inhibition non-responders can benefit from photodynamic therapy (PDT). As AMD is strongly related to gene polymorphisms, genetic factors can modify efficacy of treatment. Swept-source optical coherence tomography (SS-OCT) gives exceptional insight into the retina and choroid. SS-OCT usefulness needs to be evaluated in nAMD patients. METHODS Prospective 6-month study included consecutive 110 patients (110 eyes) with predominantly classic neovascular AMD treated with photodynamic therapy. Only non-responders to anti-VEGF were included in the study. Greatest linear dimension (GLD) of the lesion, best corrected visual acuity (BCVA), central subfield macular thickness (CSMT) and central choroidal thickness were assessed and compared between CFH and ARMS2 genotype groups. Success rate was the main endpoint. It was defined as not active CNV in the center of the fovea and no worsening in BCVA. Multiple regression was used to assess gene polymorphisms influence on PDT results. Wilcoxon tests were performed to determine significance of changes from baseline values. RESULTS Following genotype frequencies were obtained-CFH CC 35 patients (31.8%), CT 52 (47.3%), TT 23 (20.9%); ARMS2 TT 28 patients (25.4%), GT 43 (39.1%), GG 39 (35.4%) success rate in CC/CT/TT CFH and TT/GT/GG ARMS2 groups were as follows respectively: 22.9%, 28.8%, 30.4% and 28.6%, 25.6%, 28.2%. The differences were not significant with highest odds ratio TT vs. CC CFH 1.57 (95% CI 0.48-5.2, p=0.4). Significant increase in GLD was observed only in CC CFH group. Overall mean following measured parameters were obtained at baseline/day 7/month 3/month 6 (significant changes from baseline are marked with asterisk): GLD-3825±1301μm/3901±1579μm/3861±1463μm/3925±1523μm; CSMT-405±203μm/434±257μm*/321±163μm*/295±157*μm; CCT-235±103μm/278±157*μm/211±113μm*/201±107*μm; BCVA-49.3±12.5/43.2±14.2*/49.6±11.6/48.7±12.2 letters on ETDRS charts. In all patients classic component of the lesion was assessed with SS-OCT with no need to be reaffirmed in FA. Thus FA was used mainly for lesion size calculation. CONCLUSIONS Common genetic factors seem not to influence PDT effectiveness in VEGF inhibitors non-responders. SS-OCT is a valuable tool of nAMD monitoring, especially for choroid assessment. Deterioration of retinal structure and function is observed one week after PDT. It is related to increase in both retinal and choroidal thickness and is accompanied by mild temporary BCVA decrease.

Phenotype and genotype analysis in patients with macular corneal dystrophy

Aim The aim of this study was to analyse corneal morphological organisation and identify mutations in the carbohydrate sulfotransferase 6 gene (CHST6) in patients with macular corneal dystrophy originating in a Polish population. Methods Macular corneal dystrophy was diagnosed in 24 patients based on the slit-lamp exam, confocal microscopy, 1310 nm time domain and 840 nm spectral domain optical coherence tomography. 10 corneal buttons obtained from penetrating keratoplasty were processed for light microscopy. Genetic analysis of the CHST6 gene was performed, followed by a study of the sequencing results. Results Highly reflective, diffuse corneal deposits and a general increase in reflectivity were revealed with optical coherence tomography and confocal microscopy. The deposits extended from the Bowman layer to the Descemet membrane and correlated with the Alcian blue-positive granular-filamentous material into and around the stromal keratocytes confirmed by structural analysis of the corneal buttons. The genetic analysis of the blood samples identified the following mutations and single nucleotide polymorphisms: novel P64L (heterozygous), Y110C (homozygous), R162G and L200R, and M1L (heterozygous and homozygous). Conclusions Genetic mutation heterogeneity was revealed. No phenotype heterogeneity was revealed among patients with in vivo corneal morphology assessment or histological analysis.

Comparative Study of Anterior Eye Segment Measurements with Spectral Swept-Source and Time-Domain Optical Coherence Tomography in Eyes with Corneal Dystrophies

Purpose. To compare anterior eye segment measurements and morphology obtained with two optical coherence tomography systems (TD OCT, SS OCT) in eyes with corneal dystrophies (CDs). Methods. Fifty healthy volunteers (50 eyes) and 54 patients (96 eyes) diagnosed with CD (epithelial basement membrane dystrophy, EBMD = 12 eyes; Thiel-Behnke CD = 6 eyes; lattice CD TGFBI type = 15 eyes; granular CD type 1 = 7 eyes, granular CD type 2 = 2 eyes; macular CD = 23 eyes; and Fuchs endothelial CD = 31 eyes) were recruited for the study. Automated and manual central corneal thickness (aCCT, mCCT), anterior chamber depth (ACD), and nasal and temporal trabecular iris angle (nTIA, tTIA) were measured and compared with Bland-Altman plots. Results. Good agreement between the TD and SS OCT measurements was demonstrated for mCCT and aCCT in normal individuals and for mCCT in the CDs group. The ACD, nTIA, and tTIA measurements differed significantly in both groups. TBCD, LCD, and FECD caused increased CCT. MCD caused significant corneal thinning. FECD affected all analyzed parameters. Conclusions. Better agreement between SS OCT and TD OCT measurements was demonstrated in normal individuals compared to the CDs group. OCT provides comprehensive corneal deposits analysis and demonstrates the association of CD with CCT, ACD, and TIA measurements.

Complications of cataract surgery in patients with BPH treated with alpha 1A-blockers.

The prevalence of benign prostate hyperplasia (BPH) and cataract increases with age. Both diseases may develop concomitantly and may affect almost 50% of elderly men as comorbidities. Cataract is treated surgically and it has been reported that there may be an association between use of alpha-blockers for BPH, particularly alpha1A-adrenergic receptor selective drugs, and complications of cataract surgery known as Intraoperative Floppy Iris Syndrome (IFIS). The article reviews literature published on this topic and provides recommendations on how to reduce incidence of iatrogenic IFIS or its severity and outcomes in patients with BPH.