Changes of blood flow in macular zone of patients with diabetic retinopathy at different stages evaluated by optical coherence tomography angiography.

PURPOSE: To evaluate changes in macular blood flow in patients with various stages of diabetic retinopathy (DR) by optical coherence tomography angiography (OCTA). MATERIALS AND METHODS: The data of 94 patients (122 eyes) with type 2 diabetes mellitus admitted from January 2018 to May 2021 were recorded, including 31 patients (42 eyes) with no DR (NDR group), 33 patients (40 eyes) with mild non-proliferative DR (mild NPDR group) and 30 patients (40 eyes) with moderate NPDR (moderate NPDR group). Forty healthy patients (40 eyes) who were examined during the same period were selected as control group. The blood flow densities at the superficial capillary plexus (SCP), deep capillary plexus (DCP) and 300µm-wide region near the foveal avascular zone (FAZ) (FD300), FAZ area, FAZ perimeter and acircularity index (AI) were compared. Correlations of blood flow densities at the SCP, DCP and FD300, FAZ area, FAZ perimeter and AI with the severity of DR were investigated by multivariate regression analysis. A receiver operating characteristic (ROC) curve was plotted to analyze the predictive efficacy of the OCTA indices for early DR. RESULTS: Blood flow densities at the SCP, DCP and FD300 significantly decreased, while FAZ perimeter and AI increased in the NDR and DR groups compared with those of the control group (P<0.05). Blood flow densities at the SCP, DCP and FD300 of the DR group were lower than those of the NDR group, but the FAZ perimeter and AI of the former were larger (P<0.05). Blood flow densities at the SCP, DCP and FD300 in the macular zone of DR patients declined with increasing DR stage, while FAZ perimeter and AI increased (P<0.05), without collinearity among the variables. The area under the curve of FD300 for predicting early DR was highest (0.804), with a sensitivity and specificity of 84.13% and 67.19%, respectively. AI with a cut-off value of 1.05 showed the optimal specificity (87.84%) and sensitivity (73.62%) for predicting early DR. CONCLUSIONS: The flow density at FD300 declines, while FAZ perimeter and AI increase in the macular zone of patients with early DR. These three OCTA indicators show close associations with DR stage, and can function as predictors of early DR.

Macular microvascular changes in resolved central serous chorioretinopaty using spectral-domain optical coherence tomography angiography.

PURPOSE: The purpose of this study was to evaluate microvascular changes in the retina and choriocapillaris in central serous chorioretinopathy (CSCR) patients with resolved serous detachment using optical coherence tomography angiography (OCTA). METHOD: 49 eyes of 46 patients with CSCR were included in the study. 32 eyes of 16 age-matched controls were included in the control group. Fundus photography, fluorescein angiography, spectral-domain optical coherence tomography and OCTA were used. Choriocapillaris (CC) flow area, foveal avascular zone (FAZ), parafoveal vascular density of superficial and deep capillary plexus of the acute and chronic CSCR groups were compared with the values of the control group. Contrary to previous studies, OCTA data were obtained at a time when there was no serous detachment. This was because we aimed at minimizing erroneous measurements that might arise due to serous detachment. RESULTS: 1- The acute CSCR patients (1.705±0.292mm2) were found to have lower choriocapillaris (CC) flow area compared to the control group (2.155±0.069mm2). (P<0.001). Lower CC flow area was found in the chronic CSCR patients (1.774±0.216mm2) compared to the control group (2.155±0.069mm2) (P<0.001). 2- Chronic CSCR patients (49.27%±3.84) had a lower parafoveal density in the superficial capillary plexus compared to the control group (52.25%±2.85) (P<0.05). 3- No statistically significant difference was found between the acute CSCR group (55.07%±6.29) and chronic CSCR group (52.65%±5.18) in terms of parafoveal density in the deep capillary plexus when individually compared to the control group (53.34%±2.7). 4-A positive correlation was found between the parafoveal density in the deep capillary plexus and central foveal thickness (CFT) in the chronic CSCR group (r=0.382) (P˂0.05) 5- No statistically significant difference was found in the FAZ of the acute CSCR group (0.258±0.054mm2) and chronic CSCR group (0.342±0.124mm2) when individually compared to the control group (0.311±0.1mm2). The largest mean FAZ area was found in the chronic CSCR group. CONCLUSION: Our study showed that the pathogenesis of CSCR is characterized by choriocapillaris and retinal microvascular changes.

[Disc-fovea angle adjustment for peripallary retinal nerve fiber layer analysis by a spectral domain optical coherence tomography. Preliminary study]. / Analyse des fibres nerveuses rétiniennes péripapillaires ajustée selon l'angle papillo-maculaire en tomographie par cohérence optique en domaine spectral. Étude préliminaire.

INTRODUCTION: Circumpapillary retinal nerve fiber layer (cpRNFL) analysis by spectral domain optical coherence tomography (SD-OCT) has become essential for the assessment of glaucoma patients. The foveal projection is conventionally below the disc plane, creating an angle with the horizontal meridian, the disc-fovea angle. The purpose of this study is to evaluate the role of adjustment of cpRNFL analysis based on this angle. MATERIALS AND METHODS: This study concerns 40 control eyes and 55 eyes affected with and followed for primary open angle glaucoma (POAG). After precise localization of the optic disc center and the axis connecting it to the center of the fovea, a circular peripapillary scan is performed with Spectralis OCT (Heidelberg Engineering, Germany). The mean thickness in each of six papillary sectors and the global mean thickness of the cpRNFL were evaluated. The ROC (receiver operating characteristic) analysis evaluated the diagnostic capabilities of the various sectors before and after adjustment of the analysis for the disc-fovea angle. RESULTS: The disc-fovea angle was not different between the two groups (-7.0 ± 1.2° for controls vs. -6.6 ± 1.2° for POAG, P=0.70). There is a significant variance of this angle in both groups (the angle varies in the control group between -22.5° to +1.8° and in the POAG group between -18° to +2.4°). The global mean and inferior temporal (IT) thickness of the cpRNFL show the best diagnostic performance. Adjustment for disc-fovea angle does not increase the diagnostic accuracy of the various sectors analyzed. Although there is an increase in the area under the curve for the IT sector after adjustment, it is not statistically significant (0.910 ± 0.056 vs. 0.936 ± 0.045, P=0.06). CONCLUSIONS: There is a significant variation in disc-fovea angle. In this study, accounting for it does not significantly improve the diagnostic capabilities of cpRNFL in patients with POAG.

[Interest of optical coherence tomography performed immediately before intravitreal injection of anti-VEGF in exudative AMD]. / Intérêt de la tomographie à cohérence optique réalisée immédiatement avant injection intra-vitréenne d'anti-VEGF sur récidive exsudative dans la DMLA.

INTRODUCTION: Two or three systematic intravitreal injections (IVT) may be prescribed in a PRN approach to treat an exudative recurrence of neovascular age-related macular degeneration (AMD), according to the phenotype. Optical coherence tomography (OCT) may be performed immediately before the 2nd or the 3rd scheduled IVT, making it possible to cancel the procedure in the absence of exudation. The aim of the study was to evaluate the usefulness of this OCT examination and to assess the percentage of IVT cancelled, in order to evaluate a potential medico-economic benefit. METHODS: Monocentric retrospective study, in which were included 292 consecutive eyes with exudative recurrence of AMD, for which 2 or 3 IVT were scheduled between January 1st and April 30th, 2014. All patients received a first systematic IVT in the seven days following the diagnosis. Then, on the days of the 2nd and 3rd scheduled IVT, each patient had a visual acuity measurement and a Spectral domain-OCT (Spectralis, HRA Heidelberg Engineering). This measurement allowed for the IVT to be either performed as scheduled or cancelled. Both ranibizumab and aflibercept were used. A Chi(2) test was used to compare the qualitative variables and an adjusted Wilcoxon test for the quantitative values. RESULTS: Two hundred and ninety-two consecutive eyes were included; 172 in the "2 scheduled IVT" group (group A) and 120 in the "3 scheduled IVT" group (group B). At the first follow-up, 37.6% of scheduled IVT were cancelled after the OCT (44.1% in group A and 28.3% in group B). At the second follow-up, 33.3% of IVT were cancelled in group B. Overall, 150/412 (36.4%) IVT were avoided in this series. Presence of serous retinal detachment, retinal edema and increased central macular thickness were statistically correlated with confirmation of the scheduled IVT at the two follow-ups (P<0.001, P<0.001 and P=0.002, respectively). A savings of 429.80 € per patient was calculated during this short period of follow-up. CONCLUSION: An average non-injection rate of 36.4% of scheduled IVT was found in this protocol of management of recurrences with OCT performed the day of IVT. This protocol allowed to avoid unnecessary IVT one-third of the time and appeared highly cost-effective.

Calcification of a hydrophilic acrylic intraocular lens: case report with laboratory analysis.

We analyzed a single-piece plate-type hydrophilic acrylic posterior chamber intraocular lens (IOL) that was explanted due to a progressive loss of vision, which occurred 6 years after uncomplicated phacoemulsification. Gross and light microscopy, as well as anterior segment optical coherence tomography (OCT) revealed granular deposits below the IOL surface. Light scattering, as measured with Scheimpflug photography and densitometry analyses was found to be increased; spectrophotometry demonstrated a decrease in the light transmittance of the explanted lens. The granular deposits within the IOL material were found to be composed of calcium by histochemical methods (alizarin red and Von Kossa stains). To our knowledge this is the only report of calcification of this IOL design.