The Influence of Myopia on the Foveal Avascular Zone and Density of Blood Vessels of the Macula-An OCTA Study.

Background and Objectives: Myopia is the most common refractive eye anomaly with a prevalence that is constantly increasing. High myopia is associated with numerous complications that can lead to permanent vision loss. It is believed that the basis of these complications lies in changes in the microvasculature of the retina caused by an increase in the longitudinal axis of the eye. Materials and Methods: Optical coherence tomography angiography (OCTA) was used to analyze differences in macular zone vascular and perfusion density and foveal avascular zone (FAZ) parameters in myopic subjects. The following OCTA parameters were analyzed: the vessel and perfusion density of retinal blood vessels in the superficial plexus; the area, perimeter, and index of circularity of the foveal avascular zone (FAZ); and foveal and ganglion cell complex (GCC) thickness. Results: Subjects with low myopia did not show statistically significant differences compared to the control for any of the analyzed parameters. Groups with moderate and high myopia showed a significant decrease in vessel and perfusion density in the parafoveal and the entire 3 × 3 mm analyzed field. Foveal vessel and perfusion densities in the myopic groups were similar to those of the control regardless of the degree of myopia. The area and perimeter of the FAZ, as well as foveal and mean GCC thickness, did not differ significantly no matter the degree of myopia, while the index of circularity was lower in highly myopic subjects. The minimal thickness of the GCC was also lower in the high myopia group. Conclusions: High and moderate myopia led to a loss of blood vessels in the macular region. Perfusion and vascular densities were preserved in the foveal region and were not affected by different degrees of myopia. The FAZ was not significantly larger in myopic subjects, but its circularity was lower in subjects with high myopia.

Influence of Multiple Anti-VEGF Injections on Retinal Nerve Fiber Layer and Ganglion Cell-Inner Plexiform Layer Thickness in Patients with Exudative Age-Related Macular Degeneration.

Backgrounds and Objectives: To analyze the influence of multiple anti-VEGF intravitreal injections for exudative age-related macular degeneration on the thickness of peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell-inner plexiform layer (GC + IPL) using spectral domain optical coherence tomography (SD-OCT). Materials and Methods: A prospective interventional study of consecutive patients treated with intravitreal bevacizumab (IVB) was performed. Average and sectorial values of RNFL and GC + IPL thickness were recorded using Cirrus SD-OCT at 0, 6, 12, and 24 months. Patients suffering from any ocular disease that could affect RNFL or GC + IPL thickness were excluded. Results: A total of 135 patients (70 women and 65 men, aged 65 ± 15 years) were included. The average number of injections per patient was 12.4 ± 2.4. Average RNFL and GC + IPL thickness prior to the first injection (87.6 ± 12.2 and 47.2 ± 15.5 respectively), and after 24-month follow-up (86.2 ± 12.6 and 46.7 ± 11.9 respectively) did not differ significantly (p > 0.05). There was a significant decrease in GC2, GC5 segments, and minimum GC + IPL thickness. Conclusion: Repeated anti-VEGF treatment did not cause significant changes in the thickness of RNFL and GC + IPL layers over a period of 24 months. The detected decrease in GC2 and GC5 sectors, as well as in minimum GC + IPL thickness, could be a sign of ganglion cell damage induced by the treatment or could occur during the natural course of the disease.

The Determination of Type 2 Diabetes Mellitus's Impact on the Density of Retinal Blood Vessels and the Choriocapillaris: Optical Coherence Tomography Angiography Study.

Optical coherence tomography angiography (OCTA) was used to analyze the alterations in the density of retinal blood vessels and the choriocapillaris (VD) in patients suffering from type 2 diabetes mellitus (T2DM). One hundred sixty-six eyes of 83 patients (43 of whom were men and 40 women, with a mean age of 58.59 ± 14.04) with T2DM and without diabetic retinopathy were examined for the purpose of conducting the observational prospective study. The control group (CG) consisted of 66 eyes in 33 healthy subjects (15 male and 18 female, with a mean age of 55.12 ± 12.70). The measurement regions of vessel density (VD) included the deep capillary plexus (DCP), the superficial capillary plexus (SCP), and the choriocapillaris. The results indicate considerable differences in the VD of the DCP and SCP when comparing the control group with the study groups (p < 0.001). In comparison with the control group (p < 0.001), there was a statistically significant reduction in the VD of the choriocapillaris in the study group. Furthermore, patients with T2DM showed a significantly decreased VD concerning the control in different macular regions. Thickness in several macular regions in the study group significantly decreased compared to the ones in the control group. OCTA was used to gather relevant information about the vascular changes which occurred in T2DM patients, assessed through the quantitative analysis of the blood flow in the retina and choriocapillaris.

The Application of the Combination of Monte Carlo Optimization Method based QSAR Modeling and Molecular Docking in Drug Design and Development.

In recent years, one of the promising approaches in the QSAR modeling Monte Carlo optimization approach as conformation independent method, has emerged. Monte Carlo optimization has proven to be a valuable tool in chemoinformatics, and this review presents its application in drug discovery and design. In this review, the basic principles and important features of these methods are discussed as well as the advantages of conformation independent optimal descriptors developed from the molecular graph and the Simplified Molecular Input Line Entry System (SMILES) notation compared to commonly used descriptors in QSAR modeling. This review presents the summary of obtained results from Monte Carlo optimization-based QSAR modeling with the further addition of molecular docking studies applied for various pharmacologically important endpoints. SMILES notation based optimal descriptors, defined as molecular fragments, identified as main contributors to the increase/ decrease of biological activity, which are used further to design compounds with targeted activity based on computer calculation, are presented. In this mini-review, research papers in which molecular docking was applied as an additional method to design molecules to validate their activity further, are summarized. These papers present a very good correlation among results obtained from Monte Carlo optimization modeling and molecular docking studies.

Ganglion Cell-Inner Plexiform Layer Thickness in Different Glaucoma Stages Measured by Optical Coherence Tomography.

AIM: To compare ganglion cell (GCL) and inner plexiform layer (IPL) thickness in patients at different stages of primary open-angle glaucoma (POAG), determine their sensitivity and specificity values, and correlate thickness values with mean deviations (MD). METHODS: This prospective, cross- sectional study was conducted in a group of patients with confirmed POAG who were compared to an age- and gender-matched control group. Glaucomatous damage was classified according to the Hodapp-Parrish-Anderson scale: glaucoma stage 1 (early), glaucoma stage 2 (moderate), and glaucoma stage 3 (severe). The average, minimum, and all 6 sectoral (superotemporal, superior, superonasal, inferonasal, inferior, and inferotemporal) GCL + IPL thicknesses were measured and compared between groups. RESULTS: The average GCL + IPL thickness of 154 eyes of 93 patients in glaucoma stages 1, 2, 3, and 94 eyes of 47 persons in the control group were 76.79 ± 8.05, 65.90 ± 7.92, 57.38 ± 10.00, and 86.01 ± 3.68 µm, respectively. There were statistically significant differences in the average, minimum, and all 6 sectoral GCL + IPL values among the groups. The areas under the receiver operating characteristic curve for average and minimum GCL + IPL thickness values were 0.93 and 0.94, respectively, sensitivity 91.5 and 88.3%, and specificity 98.9 and 100%, respectively. Both thickness values showed significant correlations with MD. Each micrometer decrease in the average GCL + IPL thickness was associated with a 0.54-dB loss in MD. CONCLUSION: GCL + IPL layer thickness is a highly specific and sensitive parameter in differentiating glaucomatous from healthy eyes showing progressive damage as glaucoma worsens. Loss of this layer is highly correlated with overall loss of visual field sensitivity.

The Effect of LASIK Procedure on Peripapillary Retinal Nerve Fiber Layer and Macular Ganglion Cell-Inner Plexiform Layer Thickness in Myopic Eyes.

PURPOSE: To evaluate the effect of applied suction during microkeratome-assisted laser in situ keratomileusis (LASIK) procedure on peripapillary retinal nerve fiber layer (RNFL) thickness as well as macular ganglion cell-inner plexiform layer (GC-IPL) thickness. METHODS: 89 patients (124 eyes) with established myopia range from -3.0 to -8.0 diopters and no associated ocular diseases were included in this study. RNFL and GC-IPL thickness measurements were performed by spectral domain optical coherence tomography (SD OCT) one day before LASIK and at 1 and 6 months postoperatively. RESULTS: Mean RNFL thickness prior to LASIK was 93.86 ± 12.17 µm while the first month and the sixth month postoperatively were 94.01 ± 12.04 µm and 94.46 ± 12.27 µm, respectively. Comparing results, there is no significant difference between baseline, one month, and six months postoperatively for mean RNFL (p > 0.05). Mean GC-IPL thickness was 81.70 ± 7.47 µm preoperatively with no significant difference during the follow-up period (82.03 ± 7.69 µm versus 81.84 ± 7.64 µm; p > 0.05). CONCLUSION: RNFL and GC-IPL complex thickness remained unaffected following LASIK intervention.

Retinal ganglion cell/inner plexiform layer thickness in patients with Parkinson's disease.

Introduction: The aim of the paper was to analyze the changes in the macular ganglion cell layer and inner plexiform layer (GCL-IPL) thickness in patients with Parkinson's disease. Material and methods: The study enrolled 46 patients with established diagnosis of Parkinson's disease and 46 healthy subjects. Both groups were age- and gender-matched. An OCT protocol, namely standardized Ganglion Cell Analysis algorithm was used to measure the thickness of the macular GCL-IPL layer. The average, minimum, and six sectoral (superotemporal, superior, superonasal, inferonasal, inferior, inferotemporal) GCL-IPL thicknesses were measured from the elliptical annulus centered on the fovea. Results: The mean value of the clinical severity of Parkinson's disease was between 2 and 3, according to the Hoehn and Yahr scale. Statistically significant thinning of the GCL-IPL layer was registered in average and minimum GCL-IPL thickness, as well as in the sectoral layer thicknesses in patients with Parkinson's disease in comparison to the controls. There was no correlation between structural changes in the retina and disease duration or severity. A statistically significant difference in thickness between the different stages of the disease was registered only in the inferior sector. Conclusions: Parkinson's disease is accompanied by thinning of the GCL-IPL complex of macula even in the earliest stages. This may indicate a possible retinal dopaminergic neurodegeneration. There is no correlation between duration or severity of Parkinson's disease with thinning of the GCL-IPL complex. .

Foveal Avascular Zone in Normal Tension Glaucoma Measured by Optical Coherence Tomography Angiography.

AIM: To measure diameter of foveal avascular zone (FAZ), FAZ area, and vessel density using Optical Coherence Tomography Angiography (OCT-A) in patients with normal tension glaucoma (NTG) and to establish the possible role of OCT-A in diagnosis and follow-up of patients with NTG. METHODS: Twenty-one eyes of 21 patients with NTG and 30 eyes of 30 healthy subjects underwent complete ophthalmic examination as well as OCT-A on ZEISS AngioPlex. 3 × 3 macula scans were used to measure vertical, horizontal, and maximum diameter of FAZ by two graders. Mean values and interobserver variability were analyzed. Image J was used for analysis of FAZ area and vessel density. RESULTS: Mean vertical diameter (t = 5.58, p < 0.001), horizontal diameter (t = 3.59, p < 0.001), maximum diameter (t = 5.94, p < 0.001), and FAZ area (t = 5.76, p < 0.001) were statistically significantly enlarged in the NTG group compared to those in the control group. Vessel density (t = -5.80, p < 0.001) was statistically significantly decreased in the NTG group compared to that in the control group. CONCLUSION: OCT-A could have an important role in the future in diagnosis of patients with NTG. In patients with NTG, there is larger FAZ area, while the vessel density is reduced in comparison to the control group.

The efficacy of novel therapeutic modalities of isolated ocular vasculitis vs ocular vasculitis as a systemic disease.

AIM: To evaluate the efficacy of new therapeutic modalities with the observation period of three years on patients with isolated ocular vasculitis in comparison with ocular vasculitis as a systemic disease. METHODS: The effectiveness of the therapy was assessed based on the changes in visual acuity and degree of ocular inflammation (mild, medium, moderate, severe) with the following parameters: vitreous body cloudiness, blood vessels layering, macula oedema, blood vessels occlusion and new vascularisation RESULTS: New therapeutic modalities resulted in reduction in the number of patients with severe inflammation in the group of isolated ocular vasculitis from 8(13.5%) to 7(12.2%) after three years, while the number of patients with mild inflammation increased from 13(20.7%) to 18 (29.3%) in the same group (p>0.05). The number of patients with severe ocular inflammation in a group of ocular vasculitis as systemic disease increased from 3(16.2%) to 4(21.6%), because of the presence of patients with Behçet's disease. The number of patients with visual acuity less than 0.1 decreased from 11(17%) to 8(13.4%) in a group of patients with ocular vasculitis as systemic disease, which was associated with the presence of Behçet's disease too (p>0.05). CONCLUSIONS: Although the effect of new therapeutic modalities did not result in statistically significant improvement in visual acuity and reducing inflammation, systemic and intravitreal corticosteroids with steroid-sparing immunomodulatory therapy represents effective strategies in forms of isolated ocular vasculitis and ocular vasculitis as systemic disease.

Anticardiolipin antibodies in patients with Behcet's disease.

The aims of this study are to determine anticardiolipin antibodies in patients with Sy Behcet and to determine correlation between the levels of anticardiolipin antibodies in serum in patients with clinic systemic and ocular manifestations. The study was conducted on 11 patients with Behcet disease (group I), and on 11 healthy subjects (group II). Anticardiolipin antibodies -aCL were determined by the standard ELISA method, where 1GPL= 1 microgram/ml IgG aCL and 1 MPL= 1 microgram/ ml IgM, and were considered negative < 10 GPL or MPL, low positive (10-40 GPL and MPL), or high positive (>40 GPL and MPL). In the group of 11 patients with the diagnosis Sy Behcet, 6 of them were (54.5%) with values of anticardiolipin antibodies over 10 positive. In the control group of the healthy examinees aCl were positive in 2 cases (18.2%). There are no statistically significant differences in the presence of systemic clinic characteristics between aCl positive and negative patients. All the patients with SY Behcet in whom anticardiolipn antibodies were found have extremely severe visual damage which is not present in the group of those patients where the values of aCl were low. The difference is statistically significant. The level of anticardiolipin antibodies is increased in the patients with Behcet. There are no statistically significant differences in the presence of systemic clinical characteristics between aCL positive and negative patients. Visual acuity in patients with SY Behcet is statistically significantly much lower in patients who had increased values of aCL.

Ocular manifestation of rheumatoid arthritis-different forms and frequency.

Rheumatoid arthritis (RA) is a systemic inflammatory disease associated with a number of extra-articular organ manifestations. Ocular manifestations involved with RA are keratoconjunctivitis sicca, episcleritis, scleritis , corneal changes, and retinal vasculitus. The etiopathogenesis of this autoimmune disorder is still unknown. Aim of our study was to present different ocular manifestations of RA and their frequency. We have examined 691 patient with the diagnoses of RA. All examined patients were in I or II stage of the disease according to criteria of The American College of Rheumatology. Ophthalmological exam obtained: visual acuity by Snellen sings, biomicroscopy of anterior segment, Schirmer test, tear break-up time (BUT), applanation tonometry and indirect ophthalmoscopy. In all patients with retinal vasculitis fotofundus and in indicated cases fluorescein angiography was preformed. The most common manifestation of ocular involvement was keratoconjunctivitis sicca. Episcleritis was diagnosed in 5.06% patients with RA, while scleritis was present in 2.06% of patients. Diffuse scleritis was present in one patient, while nodular was present in 13 patients. There were no patients with posterior or necrotizing scleritis among examined patients. Sclerosing keratitis was diagnosed in 11 female patients. It is characterized with peripheral thickening and opacification of the stroma adjacent to the site of inflammation. Posterior scleritis or scleromalacia of cornea was not present in our patients, because all of them were in I or II stage of disease. Retinal vasculitis was present in three patients, two male and one female patient (0.45%). Ocular manifestation was present in 27.2% of patients. Women were more affected.