Optical coherence tomography and optical coherence tomography angiography findings in optic nerve hypoplasia and their relationships with visual acuity.

This study aimed to quantitatively assess the thickness of the peripapillary retinal nerve fiber layer (pRNFL) thickness, as well as the microvascular alterations in the macula and peripapillary regions, in optic nerve hypoplasia (ONH) patients compared to normal controls. This was achieved through the utilization of spectral-domain optical coherence tomography (SD-OCT) and optical coherence tomography angiography (OCTA), with a specific focus on elucidating the association between these structural alterations and visual acuity. We included a total of 17 eyes of 12 ONH patients, and 34 eyes of age-matched 34 healthy controls. The pRNFL thickness was quantified using SD-OCT, while OCTA facilitated the visualization and measurement of the microvascular structure images of the superficial retinal capillary plexus (SRCP), deep retinal capillary plexus (DRCP), and radial peripapillary capillary (RPC) segment in the macula and peripapillary area. pRNFL thickness was measured for eight sectors (superior, temporal, inferior, nasal, superotemporal, superonasal, inferotemporal, and inferonasal). SRCP, DRCP, and RPC were measured for four sectors (superior, temporal, inferior, and nasal). Age, gender, and spherical equivalent refractive errors were statistically adjusted for the analysis. Associations of structural parameters with visual acuity in ONH patients were analyzed using Spearman correlation analysis. pRNFL thickness was significantly thinner in ONH patients than in controls for all sectors. Vessel densities of temporal and nasal sectors in DRCP were significantly higher in ONH patients, but vessel densities of the inferior sector in RPC were significantly lower than those in controls. For all sectors, pRNFL thickness was strongly associated with visual acuity in ONH patients. ONH patients showed significant pRNFL thinning and microvascular alterations compared to controls, and pRNFL thickness was strongly associated with visual function. OCT and OCTA are useful tools for evaluating optic disc hypoplasia and its functional status.

Co-assessment of OCT-A and choroidal vascularity index data in multiple sclerosis patients.

OBJECTIVE: To evaluate optical coherence tomography-angiography (OCT-A) findings and choroidal vascular index (CVI) in patients with multiple sclerosis (MS). METHODS: 113 patients, including multiple sclerosis patients with optic neuritis attack (MSON+) and no optic neuritis attack (MSON-) and healthy control group (HCG), participated in this cross-sectional study. OCT-A images of all patients were taken and CVI was calculated. RESULTS: Superior flow (SF), deep flow (DF), foveal, and parafoveal superior vascular density (sVD) were decreased in the MSON+ group compared to HCG (p < 0.05). Optic disk flow (ODF) and optic disk head density (ONHD) values decreased in the MS group (p < 0.05). CVI was decreased in the MSON+ group compared to HCG (p < 0.05). There is a correlation between CVI and foveal and parafoveal sVD. CONCLUSION: Non-invasive diagnostic tools such as OCT-A and CVI can be used for early diagnosis and follow-up of microvascular pathologies in inflammatory diseases such as MS.

Changes of retinal vessel density in low to moderate myopic eyes with orthokeratology evaluated by optical coherence tomography angiography.

AIM: To explore the effect of orthokeratology (OK) fitting on retinal vessel density in low to moderate myopia adolescents by using optical coherence tomography angiography. METHODS: Children aged 10 to 14y with a cycloplegic spherical equivalent refraction of -0.50 diopter (D) to -5.00 D and astigmatism with more than -1.50 D were recruited. The enrolled adolescents were divided into OK group and spectacle group. During regular follow-up, adolescents were measured respectively at pre-wear, 1, 3, and 6mo after treatment. The follow-up included uncorrected distance visual acuity (UDVA), axial length (AL), superficial capillary plexus density (SCPD), deep capillary plexus density (DCPD), central retinal thickness (CRT), foveal avascular zone area (FAZ-A), foveal avascular zone perimeter (FAZ-P) and foveal vessel density in a 300-µm-wide region around foveal avascular zone (FD-300). The collected data were analyzed using statistical methods. RESULTS: By one month, SCPD significantly increased in the fovea and superior retina, and DCPD significantly increased inferiorly in OK group compared to spectacle group (P<0.05). By three months, there were significant increases in SCPD in the fovea and inferior retina, and DCPD in the parafovea, superior, and inferior retina in OK group (P<0.05), while the increase in SCPD and DCPD in the fovea were observed by six months (P<0.05). The FD-300 significantly increased at every follow-up in OK group compared to spectacle group (P<0.05). No significant differences in the CRT, FAZ-A and FAZ-P and FD-300 were observed between two groups (P>0.05). OK group showed a significant improvement in UDVA after wearing OK, compared to spectacle group (P<0.01), while the AL did not show a significant difference between two groups (P>0.05). CONCLUSION: Short-term OK worn can increase local retinal vessel density in adolescents with low-to-moderate myopia.

Evaluation of retinal microvascular network in patients with systemic sclerosis: An optical cohorence tomography angiography study.

PURPOSE: To investigate the long-term effect of systemic sclerosis on the optic disk and retinal capillary network and to see whether the drugs used in the treatment of SSc affected optical coherence tomography angiography (OCTA) parameters. MATERIALS AND METHODS: This cross-sectional case-control study included 40 systemic sclerosis patients and 40 healthy individuals. We included only one eye of each patient in the study. Macular layers and angiography scanning were performed with a Zeiss Cirrus 5000 OCTA system. Such values as macular thickness, retinal nerve fiber layer (RNFL), ganglion cell inner plexiform layer (GC-IPL) were obtained. For central vessel and perfusion density (VD, PD), central 6 mm were obtained and were evaluated by dividing it into 3 groups as inner, outer, and full. The FAZ was evaluated through 3 parameters: area, perimeter, circularity index. RESULTS: Statistically significant difference was found between the groups in terms of the mean and foveal macular thickness values (p=0.008, p=0.033). Significant differences were also found between the two groups in terms of the VD and PD parameters in all regions except for 1 mm center (p<0.05). There were no significant differences in RNFL and GC-IPL values between two groups. Also, a positive correlation was observed between parapapillary perfusion density values and RNFL and GC-IPL thicknesses in SSc group. When the subgroups were compared in terms of vasodilator drug use, the subgroup using vasodilators was seen to have higher mean RNFL and inferior RNFL thicknesses (p=0.045 and p=0.035, respectively). In addition, there was a significant positive correlation between parapapillary VD and RNFL values in the SSc subgroup treated with vasodilators. CONCLUSIONS: The results of this study demonstrate microvascular loss in individuals with systemic sclerosis, compared with healthy subjects. Also, it has been determined that OCTA is an important test for screening retinal and optic disk microvascular changes over time in cases of systemic sclerosis and may be used to evaluate the response to vasodilator drugs used in the treatment of SSc disease.

Investigation of Retinal Vascular Parameters and Choroidal Vascular Index in Patients Developing Hyphema After Unilateral Blunt Trauma.

BACKGROUND: To evaluate retinal and choroidal vascular changes in cases with hyphema after blunt ocular trauma that did not cause globe rupture or any retinal pathology. METHODS: This cross-sectional study included 29 patients who developed hyphema after unilateral blunt ocular trauma (BOT). The other healthy eyes of the same patients were evaluated as the control group. Optical coherence tomography-angiography (OCT-A) was used for imaging. In addition, choroidal parameters were compared by calculating the choroidal vascular index (CVI) and using choroidal thickness measurements by two independent researchers. RESULTS: Superior and deep flow values were significantly decreased in the traumatic hyphema group compared to the control group (p<0.05). Parafoveal deep vascular density (parafoveal dVD) values were decreased in traumatized eyes compared to control eyes (p=0.000). Vascular density values were similar other than that. In addition, there was a significant decrease in optic disc blood flow (ODF) and optic nerve head density (ONHD) values compared to the control group (p<0.05). In addition, no significant difference was observed between the groups in terms of mean CVI values (p>0.05). CONCLUSION: Non-invasive diagnostic tools such as OCTA and EDI-OCT can be used to detect and monitor early changes in retinal and choroidal microvascular flow in cases of traumatic hyphema.

Studies of the retinal microcirculation using human donor eyes and high-resolution clinical imaging: Insights gained to guide future research in diabetic retinopathy.

The microcirculation plays a key role in delivering oxygen to and removing metabolic wastes from energy-intensive retinal neurons. Microvascular changes are a hallmark feature of diabetic retinopathy (DR), a major cause of irreversible vision loss globally. Early investigators have performed landmark studies characterising the pathologic manifestations of DR. Previous works have collectively informed us of the clinical stages of DR and the retinal manifestations associated with devastating vision loss. Since these reports, major advancements in histologic techniques coupled with three-dimensional image processing has facilitated a deeper understanding of the structural characteristics in the healthy and diseased retinal circulation. Furthermore, breakthroughs in high-resolution retinal imaging have facilitated clinical translation of histologic knowledge to detect and monitor progression of microcirculatory disturbances with greater precision. Isolated perfusion techniques have been applied to human donor eyes to further our understanding of the cytoarchitectural characteristics of the normal human retinal circulation as well as provide novel insights into the pathophysiology of DR. Histology has been used to validate emerging in vivo retinal imaging techniques such as optical coherence tomography angiography. This report provides an overview of our research on the human retinal microcirculation in the context of the current ophthalmic literature. We commence by proposing a standardised histologic lexicon for characterising the human retinal microcirculation and subsequently discuss the pathophysiologic mechanisms underlying key manifestations of DR, with a focus on microaneurysms and retinal ischaemia. The advantages and limitations of current retinal imaging modalities as determined using histologic validation are also presented. We conclude with an overview of the implications of our research and provide a perspective on future directions in DR research.

Evaluation of ocular microvascular characteristics in smokers and patients with chronic obstructive pulmonary disease using an optical coherence tomography angiography.

PURPOSE: To investigate retinal microvascular changes in patients with chronic obstructive pulmonary disease (COPD) using optical coherence tomography angiography (OCTA) and to compare these values with those of smokers and healthy non-smokers. METHODS: This study was performed on 38 eyes of 38 patients with COPD, 30 eyes of 30 smokers, and 31 eyes of 31 healthy non-smokers. Foveal avascular zone (FAZ) area, superficial (SCP) and deep (DCP) capillary plexus (whole image, fovea, parafovea, and perifovea) and radial peripapillary capillary (RPC) vessel densities (whole image, peripapillary, and inside disc) were evaluated via OCTA device (Optovue, Fremont, CA, USA). The forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) ratio and FEV1 values of patients with COPD were recorded. RESULTS: There were statistically similar values in smoking pack-years between the smoker and COPD groups (p = 0.059). Entire SCP and DCP vessel densities were significantly different among the all groups (p < 0.05); for these parameters, the control group had the highest and the COPD group had the lowest vessel density values. Significantly decreased RPC vessel densities in all regions were detected in the COPD group compared with the other groups. Multiple regression analysis showed significant positive correlations between the FEV1 and the SCP, DCP, and RPC vessel densities (for all, p < 0.05). CONCLUSIONS: This study detected lower vessel densities in patients with COPD than in smokers and healthy controls and reported decreased vessel density measurements with increasing COPD severity. COPD patients with or without a history of smoking may benefit from higher prioritization in terms of ophthalmic screening to prevent ocular complications.

Reduced contrast sensitivity function correlated with superficial retinal capillary plexus impairment in early stage of dysthyroid optic neuropathy.

BACKGROUND: To assess the accuracy of contrast sensitivity function (CSF) in detecting dysthyroid optic neuropathy (DON) at an early stage in thyroid-associated ophthalmopathy (TAO) patients and to examine potential factors that may be linked to early visual impairments in these individuals. METHODS: A total of 81 TAO patients (50 non-DON and 31 DON), and 24 control subjects participated in the study. CSF was measured with the quick CSF (qCSF) method. Optical coherence tomography angiography (OCTA) images of the ganglion cell complex layer (GCCL), superficial and deep retinal capillary plexuses (SRCP and DRCP) in a 3 mm diameter area around the macula were evaluated. RESULTS: Compared with the controls, the area under the log contrast sensitivity function (AULCSF) and SRCP density were significantly reduced in non-DON and DON patients (all P < 0.05). The GCCL thickness of the DON patients was thinner than that of the controls and non-DON patients (all P < 0.05). The AULCSF was significantly correlated with spherical equivalent refractive error, muscle index, SRCP density and GCCL thickness in TAO patients, respectively (all P < 0.05). However, stepwise multi-regression analysis showed that the AULCSF was only significantly correlated with SRCP density (P < 0.001). Receiver operating characteristic curve analysis showed that the AULCSF produced the most accurate discrimination between non-DON and DON patients from the controls (AUC = 0.831, 0.987, respectively; all P < 0.001). CONCLUSIONS: CSF change in the early stage of DON is related to SRCP density. It can be an early indicator of visual impairments associated with DON in TAO patients.

[The role of optical coherence tomography angiography in the assessment of retinal microcirculation in thrombotic microangiopathy associated with malignant arterial hypertension]. / Rol' opticheskoi kogerentnoi tomografii s funktsiei angiografii v otsenke retinal'noi mikrotsirkulyatsii pri tromboticheskoi mikroangiopatii, assotsiirovannoi so zlokachestvennoi arterial'noi gipertenziei.

Optical coherence tomography angiography (OCT-A) allows detailed assessment of the state of local blood flow in various systemic ischemic diseases, which include thrombotic microangiopathy (TMA) associated with malignant arterial hypertension (MAH). PURPOSE: To evaluate retinal microcirculation using OCT-A imaging data in the group of patients with TMA associated with MAH. MATERIAL AND METHODS: The study consisted of a qualitative and quantitative analysis of OCT-A data from 7 patients (14 eyes) with TMA associated with MAH and verified by renal biopsy. The control group included 7 healthy individuals (14 eyes). The following parameters were analyzed: area size of the foveal avascular zone FAZ, mm, vessel density (VD, %) and vessel skeleton density (VSD, %). The indicators were measured separately in the deep and superficial vascular plexuses and divided by localization into: the total density of the entire measured area, central density, density by quadrants (superior, inferior, nasal and temporal). All quadrants were subdivided into inner (corresponding to parafovea) and outer (corresponding to perifovea). RESULTS: Local foci of vascular attenuation of the deep retinal capillary plexus, pathological tortuosity of blood vessels in the deep and superficial retinal capillary plexuses were found in 100% of study group patients. Per-quadrant analysis of OCT-A finding in the macular zone revealed a statistically significant decrease in VD of the deep retinal capillary plexus (p<0.05). A direct correlation was found between glomerular filtration rate and the VD index in the outer inferior (r=0.567; p=0.034) and inner temporal quadrants (r=0.613; p=0.020) of the deep retinal capillary plexus, as well as the level of hemoglobin in blood serum and VD in inner temporal quadrant of the deep vascular plexus (r=0.596; p=0.025). CONCLUSION: Changes revealed with OCT-A are the symptoms of TMA in MAH patients spreading to the retinal microvasculature, mainly at the level of the deep retinal capillary plexus.

Age- and sex-related differences in the retinal capillary plexus in healthy Chinese adults.

BACKGROUND: To assess age- and sex-related changes in the superficial retinal capillary plexus (SCP) and deep retinal capillary plexus (DCP) in healthy Chinese adults. METHODS: In this cross-sectional study, all data were derived from the community-based Jidong Eye Cohort Study. Participants underwent optical coherence tomography angiography (OCTA) and other ocular and systemic examinations. The vessel densities of the whole measured area, parafovea, and four quadrants in the SCP and DCP were measured. RESULTS: We recruited 1036 eyes of 1036 healthy participants; the mean age was 40.4 ± 9.8 years, and 449 (43.3%) participants were males. The SCP and DCP vessel densities in all regions, except for temporal and nasal regions in the SCP, non-linearly decreased with age. The DCP vessel densities began to decrease at approximately 35 years of age, while the SCP vessel densities began to decrease at approximately 40 years of age. The DCP vessel densities decreased more rapidly than the SCP vessel densities at 35-50 years of age. The DCP vessel densities remained stable or slightly decreased after the age of 50 years in females, while those decreased linearly in most regions in males. CONCLUSIONS: The retinal vessel density decreased earlier and more rapidly in the DCP than in the SCP, and the effect of aging on the DCP vessel density was sex-dependent. Our findings suggest that age and sex should be considered when interpreting clinical quantitative OCTA data.

Repeatability and Reproducibility of Retinal Fractal Dimension Measured with Swept-Source Optical Coherence Tomography Angiography in Healthy Eyes: A Proof-of-Concept Study.

The retinal vascular network fractal dimension (FD) could be a promising imaging biomarker. Our objective was to evaluate its repeatability and reproducibility in healthy eyes. A cross-sectional study was undertaken with young, healthy volunteers who had no reported cardiac risk factors or ocular disease history. For each participant, three SS-OCTA images (12 × 12 mm) were acquired using the Plex Elite 9000 (Carl Zeiss Meditec AG, Jena, Germany) by two ophthalmologists. Automated segmentation was obtained from both the superficial and deep capillary plexuses. FD was estimated by box counting. The intraclass correlation coefficients (ICC) were used as measures for repeatability and reproducibility. A total of 43 eyes of healthy volunteers were included. The mean ± standard deviation (SD) age was 30 ± 6.2 years. The results show good repeatability. The ICC was 0.722 (95% CI, 0.541-0.839) in the superficial capillary plexus and 0.828 (95% CI, 0.705-0.903) in the deep capillary plexus. For reproducibility, the ICC was 0.651 (95% CI, 0.439-0.795) and 0.363 (95% CI, 0.073-0.596) at the superficial and deep capillary plexus, respectively. In this study, the FD of the vascular network measured via SS-OCTA showed good repeatability and reproducibility in healthy participants.

Decreased Vessel Density in Retinal Capillary Plexus and Thinner Ganglion Cell Complex Associated With Cognitive Impairment.

Background: To determine the association of the retinal capillary plexus (RCP) and ganglion cell complex (GCC) with cognitive impairment using optical coherence tomography angiography (OCTA). Methods: A cross-sectional, community-based study utilizing data from the participants enrolled between August 2019 and January 2020 in the Jidong Eye Cohort Study. We assessed the vessel density in RCP and GCC thickness using OCTA, and cognitive testing using the Montreal Cognitive Assessment (MoCA). Cognitive impairment in this study was defined as MoCA score < 24. We used multivariable analysis to evaluate the association of RCP and GCC with cognitive impairment after adjusting for confounders. Results: This study analyzed 1555 participants. The mean age of participants was 52.3 (8.4) years, and 861 (55.4%) were women. Cognitive impairment was observed in 268 (17.2%) participants. The adjusted odds ratio (OR) with 95% confidence interval (95% CI) for parafovea vessel density in the deep RCP with cognitive impairment was 1.20 (1.03-1.39). For vessel area and length density surrounding foveal avascular zone with cognitive impairment, the ORs with 95% CIs were 1.23 (1.07-1.41) and 1.30 (1.13-1.49), respectively. For thickness in the superior GCC with cognitive impairment, the OR with 95% CI was 1.16 (1.01-1.32). Conclusion: Lower vessel density in the RCP and thinner GCC were associated with cognitive impairment. Our results suggest that alterations in the RCP and GCC could provide further evidence when assessing the cognitive function and may even be potentially useful biomarkers in the detection of cognitive impairment.

Association of Serum Uric Acid With Retinal Capillary Plexus.

Background: To determine the association between serum uric acid (SUA) and the retinal capillary plexus (RCP) using optical coherence tomography angiography (OCTA). Methods: This cross-sectional study evaluated data from August 2019 to January 2020 from participants recruited from the Jidong community (Tangshan, Hebei, China). All participants completed detailed anthropometrical measurements, laboratory tests and comprehensive ophthalmic examinations. We assessed the vessel density in RCP using OCTA. We used multivariable analysis to evaluate the sex-specific association between SUA and RCP after adjusting for confounders. Results: A total of 2730 participants were included in this study. The mean age of the participants was 44.0 ± 11.6 years, and 1463 (53.6%) were women. The multivariable ßs and 95% confidence intervals (CIs) of superficial RCP vessel density in the second through fourth SUA quartiles compared with the lowest SUA quartiles were -0.27 (-0.56 - 0.03), -0.30 (-0.60 - 0.01), and -0.46 (-0.78 - -0.14) (P for trend = 0.007) in men. Conclusions: Higher SUA levels were significantly associated with lower RCP vessel density in men. Our findings provide evidence for the detrimental effect of high SUA levels on the retinal microvasculature and imply the importance of modulating SUA to prevent the microvascular alternation especially for men.

Association of cigarette smoking with retinal capillary plexus: an optical coherence tomography angiography study.

PURPOSE: To investigate the association between cigarette smoking and retinal capillary plexus (RCP) using optical coherence tomography angiography (OCTA) and to examine whether potential vascular risk factors could impact their association. METHODS: This is a cross-sectional, community-based study. The Jidong Eye Cohort Study included participants aged ≥18 years in the Jidong community (Tangshan city, northern China) from August 2019 to January 2020. All participants underwent comprehensive ophthalmic examination and completed detailed smoking questionnaires. Retinal vessel density in the superficial and deep RCP was automatically measured using OCTA. RESULTS: Of the 2598 participants included in the study, 2026 (78.0%) never smoked and 572 (22.0%) had a history of smoking (494 [19.0%] current smokers and 78 [3.0%] former smokers). The median (interquartile range) age was 41 (34-52) years for the non-smoking group and 45 (35-54.5) years for the smoking group. Multivariable analysis showed that smoking history is associated with a low deep RCP vessel density in the parafovea (ß, -0.53; 95% confidence interval [CI], -0.82 to -0.24) and four quadrants. Increased smoking pack-years were associated with reduced deep RCP vessel density in the parafovea (p for trend <0.001) and four quadrants. The significant interaction between diabetes and smoking only was found for superficial RCP vessel density in the parafovea (p for interaction = 0.014) and four quadrants except for the temporal quadrants. CONCLUSIONS: Cigarette smoking is an independent risk factor for reduced deep RCP vessel density. Our findings imply the potential detrimental effect of smoking on the occurrence of ocular diseases.

Quantitative analysis of early retinal vascular changes in type 2 diabetic patients without clinical retinopathy by optical coherence tomography angiography.

PURPOSE: To investigate the quantitative differences in optical coherence tomography angiography (OCTA) data between type 2 diabetes patients without clinically detectable diabetic retinopathy (DR) and healthy subjects. METHODS: Thirty-nine patients with type 2 diabetes without DR and 41 age- and sex-matched healthy controls were recruited. The vessel density and foveal avascular zone (FAZ) area in the superficial capillary plexus and deep capillary plexus were measured using Nidek RS-3000 Advance® and compared between patient cohorts. Foveal vessel density (%) and FAZ (%) were also calculated. RESULTS: A significant decrease in vessel density has been observed in the deep capillary plexus of the patients compared to healthy individuals (5.58 ± 0.98 mm2 versus 6.15 ± 0.89 mm2, p < 0.001). However, there were no significant differences in other parameters between cohorts (p > 0.05 in all parameters). Despite the decrease of deep capillary plexus density in the macular region, there was no significant change observed in foveal vessel density (p:0.44). It has also been observed that the duration of diabetes mellitus correlates with vessel density decrease in deep capillary plexus (R:-0.52; p < 0.001). In both groups, all parameters in deep capillary plexus were significantly higher than superficial capillary plexus (p < 0.001 for all parameters). CONCLUSIONS: OCTA can identify quantitative changes in DCP before the manifestation of clinically apparent retinopathy. DCP-VD reduction may be an earlier finding than FAZ enlargement. Despite the reduction of VD, FVD could be preserved for a certain period of time in DM patients.

Case Report: Optical coherence tomography angiography findings in radiation retinopathy.

We reported the observation of a 31-year-old female followed for a nasopharyngeal carcinoma since 2009, treated by locoregional radiotherapy, with a cumulative dose of 75 Gray. The patient presented with a progressive decline in bilateral vision. Ophthalmologic examination revealed bilateral dry eye, posterior subcapsular cataract, radiation retinopathy, and optic neuropathy. The patient presented all ocular complications of radiotherapy. The most severe was radiation retinopathy. Performing optic coherence tomography angiography (OCT-A) earlier could have speeded up the diagnosis and led to a better prognosis. The OCT-A showed more pronounced macular edema in the right eye, and revealed enlargement of the central avascular zone and loss of the deep and superficial retinal vascular network. The patient received three consecutive monthly intravitreal injections of anti-vascular endothelial growth factor. Yet, we noted a non-improved visual acuity. The aim of this case report was to present the contribution of OCT-A in the diagnosis of radiation maculopathy and attribute these changes to ischemia at the level of the retinal vascular network.

OCT retinal angiography features in patients with rheumatoid arthritis: A pilot study.

PURPOSE: To evaluate the superficial (SCP) and deep retinal capillary plexus (DCP) by mean of optical coherence tomography angiography (OCTA) in treatment-naïve patients affected by rheumatoid arthritis (RA). METHODS: Between March 2019 and January 2020, patients with recent diagnosis of "definite RA" based on 2010 Rheumatoid Arthritis Classification Criteria were included in a Prospective, observational single center case-control study carried out at G.B. Bietti Foundation. Data were compared with those of 16 healthy age- and sex-matched subjects. Values of the vessel density (VD) of SCP and DCP, central foveal thickness (CFT), foveal avascular zone (FAZ) were collected by mean of OCTA. Main outcome measure was the VD alteration of SCP and DCP in treatment-naïve RA-patients. RESULTS: No difference in age, sex-distribution, best-corrected visual acuity, CFT was registered between the two groups. OCTA data analysis showed in RA-patients a statistically significant reduction in the VD in the mean global area, inner ring, especially in the superior quadrant of the SCP. A trend of VD reduction was also registered in temporal, nasal, and inferior quadrants, respectively, although it did not reach a statistically significant value. Assessment of VD of DCP and FAZ area did not evidence any difference among the groups. CONCLUSIONS: OCTA allows to highlight the vascular remodeling of the retinal microcirculation in RA-patients, even in early stages of the disease, demonstrating a reduction of VD. Outcomes of the current investigation can provide new insight in the pathogenetic mechanism of RA and extend the potential applications of this diagnostic tool.

Acute Macular Neuroretinopathy in a Patient with Retinal Vascular Tortuosity.

We report a rare case of a young woman with acute macular neuroretinopathy (AMN) in the right eye and concomitant retinal vascular tortuosity in both eyes. A 19-years-old woman presented with a sudden loss of central vision in the right eye. Apart from flu-like infection 2 weeks before the onset of symptoms, she reported overall good health. She used oral contraceptive pills. Multimodal imaging techniques including color fundus photography, fundus autofluorescence, infrared reflectance imaging, fluorescein angiography, swept-source optical coherence tomography (SS-OCT), and visual field assessment were used for the diagnosis of AMN as well as disease monitoring during follow-up. At presentation, ophthalmoscopy revealed a reddish parafoveal lesion, while SS-OCT showed hyper-reflectivity in the outer plexiform and outer nuclear layers with a slightly disrupted inner segment/outer segment junction. All these imaging findings indicated AMN, but the interpretation was slightly difficult due to the presence of tortuous retinal arteries in both eyes. During the disease course, functional and morphological recovery was documented at 1- and 6-month follow-up. However, as the abnormal appearance of the retinal vessels did not change, congenital retinal vascular tortuosity was diagnosed. Since the pathogenesis of AMN has not been fully elucidated, there is currently no effective treatment. Numerous studies have emphasized a vascular origin and the key role of ischemia in AMN. Our rare case suggests that congenital tortuosity of the retinal vessels, although constituting a common finding in healthy individuals, may be involved in the pathophysiology of the disease.

Investigation of Retinal Vascular Changes during Pregnancy Using Optical Coherence Tomography Angiography.

Purpose: To investigate retinal vascular changes in pregnant women using optical coherence tomography angiography (OCTA).Materials and Methods: This prospective, cross-sectional study included 97 pregnant women and age-matched 34 healthy control subjects. The OCTA parameters of one eye (left) of pregnancy group and control group were compared. Besides, the OCTA parameters of three trimesters were compared between themselves and the control group. The foveal avascular zone (FAZ) area and the vessel density percentages of the superficial capillary plexus (SCP), deep capillary plexus (DCP), and radial peripapillary capillary (RPC) of all the groups were evaluated by OCTA.Results: In the pregnancy group, the vessel density of DCP was higher in all regions than the control group except the foveal region, but this difference could not reach statistical significance. On the other hand, the vessel density of SCP in the pregnancy group did not show a manifest change in all regions except the foveal region as in DCP. Although the FAZ area was wider in pregnancy group, this difference was not statistically significant (p:0.661). There was no statistically significant difference observed in vessel density of SCP, DCP, and RPC between the different trimesters and the control group, and none of these data correlated with the gestational week.Conclusion: This study showed retinal vascular changes secondary to pregnancy, especially in the vessel density of DCP. These results can provide information that should be taken into account in the evaluation and investigation of pregnancy-specific retinal vascular pathologies.

Differential patterns of parafoveal and peripapillary vessel density in multiple sclerosis and neuromyelitis optica spectrum disorder.

BACKGROUND: To compare intraocular microvascular alterations between patients with multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) using optical coherence tomography angiography (OCT-A). METHODS: Sixty patients were included in the study, 23 MS patients (36 eyes) and 37 NMOSD patients (47 eyes), all with a history of optic neuritis (ON). All subjects underwent comprehensive ophthalmic examinations, OCT-A, and high-definition-OCT imaging. OCT-A was used to measure the vessel density of the superficial and deep retinal capillary plexus (SRCP and DRCP) in the macular area and the radial peripapillary capillary (RPC) segment. Age, spherical equivalent, and gender were adjusted for in the analyses. RESULTS: Patients with NMOSD showed significantly decreased vessel density of the SRCP (average, p = 0.0007; superior, p = 0.0009; inferior, p = 0.0002) and RPC segment (average, p < 0.0001; superior, p = 0.0004; inferior, p = 0.0052; temporal, p < 0.0001; nasal, p = 0.0001) compared to the MS patients. Parafoveal and peripapillary vessel density was significantly associated with the OCT parameters in both the MS and NMOSD patients. Parafoveal and peripapillary vessel density in the MS patients was significantly associated with visual function, including visual acuity and visual field defects, whereas only peripapillary vessel density was significantly associated with visual function in the NMOSD patients. CONCLUSION: We demonstrated parafoveal and peripapillary vascular alterations between MS and NMOSD patients that varied in degree and pattern. We also found associations between vessel density and structural and functional parameters in MS and NMOSD patients. Further studies are needed to facilitate a greater understanding of the pathogenesis and its association with vascular alterations in these disorders.