Deep Capillary Plexus Vessel Density Research Articles

Retinochoroidal vascular plexuses in patients with iron deficiency anaemia

ABSTRACT Clinical relevance Optical coherence tomography angiography (OCT-A) may enable the identification of alteration in the retinochoroidal microvasculature in patients with iron deficiency anaemia. Background To investigate the presence of macular microvascular alterations in females with IDA by using OCT-A. Methods This is a cross-sectional comparative study. Forty patients with IDA and 35 age-matched healthy women underwent a complete ophthalmologic examination and OCT-A imaging. Foveal avascular zone parameters and the vessel density in the superficial (SCP) and deep capillary plexus (DCP) were calculated using automated software. All measurements were compared between groups. Correlations between the OCT-A metrics and haematological laboratory parameters were evaluated. Results Compared to healthy subjects, IDA patients revealed significantly decreased vessel density of the SCP in all parafoveal quadrants (p < 0.05). In contrast, vessel density analysis in DCP has shown no statistically significant difference in all parafoveal quadrants (p > 0.05). Although foveal vessel density in both SCP and DCP were higher in the IDA group, only the foveal vessel density in DCP was significantly higher than controls (p = 0.001). The mean values of the foveal avascular zone area and perimeter and choriocapillaris flow area were significantly lower in the IDA group (p < 0.05). The parafoveal vessel density in SCP, foveal avascular zone area, and choriocapillaris flow area were positively correlated with haematological parameters including haemoglobin, haematocrit, mean corpuscular haemoglobin, and mean corpuscular volume (p < 0.01). Conclusion Patients with IDA had decreased parafoveal vessel density in the SCP, but not the DCP. Foveal avascular zone metrics and choriocapillaris flow area measurements were significantly lower in IDA.

Retinal and Optic Disc Vascular Changes in Patients Using Long-Term Tadalafil: A Prospective Non-Randomized Matched-Pair Study.

Retinal, choroidal and optic disc vascularity has never been evaluated in patients taking PDE5is long-term. The aim of our study was to evaluate the neurostructural and vascular changes after long-term use of tadalafil, using spectral domain (SD)-optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). In the present clinical trial, 27 patients who have been taking tadalafil 20 mg on alternate days (OAD) for at least 6 months (Group A) were enrolled. The matched group consisted of 27 healthy men (Group B). Both groups of patients underwent SD-OCT to study ganglion cell complex (GCC), retinal nerve fiber layer (RNFL) and choroidal thickness and OCTA for the evaluation of superficial capillary plexus (SCP), deep capillary plexus (DCP), choriocapillaris (CC) and radial peripapillary capillary (RPC). A reduction in SCP, DCP and RPC vessel density was found in patients using tadalafil long-term. Retinal and optic disc toxicity may be detected using modifications of capillary vessel density. Further studies are needed to investigate the possibility of a causal association.

Superficial and Deep Macula Vessel Density in Healthy, Glaucoma Suspect, and Glaucoma Eyes.

Macular superficial capillary plexus (SCP) vessel density is more informative than deep capillary plexus (DCP) vessel density for the detection of glaucoma. The purpose of this study was to characterize optical coherence tomography angiography macular SCP and projection-resolved DCP vessel densities and compare their diagnostic accuracies with ganglion cell complex (GCC) thickness in healthy, glaucoma suspect, and glaucoma eyes. Sixty-eight eyes of 44 healthy subjects, 26 eyes of 16 preperimetric glaucoma suspects, and 161 eyes of 124 glaucoma patients from the Diagnostics Innovations in Glaucoma Study with good quality high-density 6×6 mm2 macula optical coherence tomography angiography images were included. The diagnostic accuracy of SCP vessel density, projection-resolved DCP vessel density and GCC thickness were compared among groups. Mean whole image vessel density (wiVD; % of area occupied by vessels containing flowing blood) in the SCP layer was highest in healthy eyes (49.7%), followed by glaucoma suspect eyes (46.0%), and glaucoma eyes (40.9%) (P<0.001). Mean wiVD in the DCP layer was similar in healthy (50.6%), glaucoma suspect (47.3%), and glaucoma eyes (45.7%) (P=0.925). Diagnostic accuracy of both GCC thickness and SCP wiVD was significantly higher than DCP wiVD for classifying healthy and glaucoma eyes [adjusted area under the receiver operating characteristic curve (95% confidence interval): GCC=0.86 (0.72, 0.94), SCP=0.80 (0.66, 0.91) and DCP=0.44 (0.30, 0.57)] (P<0.001). SCP vessel densities have better diagnostic accuracy for detecting glaucoma than DCP vessel densities. Although the diagnostic accuracy of the macula SCP is relatively modest, it is more informative than the DCP.

Reduced Retinal Microvascular Perfusion in Patients With Stroke Detected by Optical Coherence Tomography Angiography.

Currently there is a shortage of biomarkers for stroke, one of the leading causes of death and disability in aging populations. Retinal vessels offer a unique and accessible “window” to study the microvasculature in vivo. However, the relationship between the retinal microvasculature and stroke is not entirely clear. To investigate the retinal microvascular characteristics in stroke, we recruited patients with stroke and age-matched control subjects from a tertiary hospital in China. The macular vessel density (VD) in the superficial capillary plexus (SCP) and deep capillary plexus (DCP), foveal avascular zone (FAZ) metrics, and optical coherence tomography angiography (OCTA) measured optic disc VD were recorded for analysis. A total of 189 patients with stroke and 195 control subjects were included. After adjusting for sex, visual acuity, systolic and diastolic blood pressure, a history of smoking, levels of hemoglobulin (HbA1c), cholesterol, and high-density lipoprotein (HDL), the macular VD of SCP and DCP in all sectors was decreased in patients with stroke. In the stroke group, the VD around the FAZ and the VD of the optic disk were lower. Logistic regression found the parafovea-superior-hemi VD of DCP > 54.53% [odds ratio (OR): 0.169] as a protective factor of stroke. Using the integration of all OCTA parameters and traditional risk factors, the area under the receiver operating characteristic (AUC) curve of distinguishing patients with stroke was 0.962, with a sensitivity of 0.944 and a specificity of 0.871. Our study demonstrates that the retinal VD is decreased in patients with stroke independently of the traditional risk factors of stroke, which may shed light on the monitoring of stroke using the retinal microvascular parameters.

Evaluation of the direct effects on retinal and choroidal microvascularity of systemic scleroderma

ObjectiveOcular involvement in systemic sclerosis (SSc) has been documented; however it cannot be distinguished from secondary changes due to concomitant hypertension.Therefore, the aim of this prospective cross-sectional study was to demonstrate the direct effects of Ssc on retinal and choroidal microvasculature in patients without hypertension. Methods47 SSc patients and 44 age- and sex-matched healthy control subjects were enrolled in this study. In fundus examination: Increased vascular tortitis, focal or general arteriolar narrowing, arteriovenous notch, severe exudation, microhemorrhage, and pigment epithelial changes in the retina of SSc patients without hypertension were investigated. Patients with at least two of the above findings were considered to have retinopathy After that, patients were divided into two groups according to the presence of retinopathy in this study. Retinal and choroidal microvasculature were evaluated using optical coherence tomography angiography. ResultsThere was a significant decrease in SSc patients with retinopathy in both superficial capillary plexus vessel density (SCP VD) and deep capillary plexus vessel density (DCP VD) compared to the control group. Full avascular zone (FAZ) evaluation tool variables (FAZ area, FAZ perimeter, foveal density) were significantly lower in all Ssc patients than in the healthy control group. It was found that the flow in the 1 mm and 3 mm circular area (Outer Retina 1–3 mm Flow Area) increased significantly in Ssc patients with retinopathy. Choroidal flow (Choriocapillaries 1 mm Flow Area) was statistically lower in Ssc patients with retinopathy. ConclusionsWe have showed an increase in the outer retina 1–3 mm flow area (circular area of the outer retina fold covering the fovea) despite the decrease in vascular density and choroidal thickness in scleroderma patients with retinopathy. Hence, we first demonstrated that Ssc itself may have an effect on retinal and choroidal microvasculature, independent of hypertension.

Repeatability of Optical Coherence Tomography Angiography Measurements in Patients with Retinal Vein Occlusion.

PurposeTo analyze the repeatability of vessel density (VD) measurements and manual foveal avascular zone (FAZ) measurements using optical coherence tomography angiography (OCTA) in patients with retinal vein occlusion (RVO) without macular edema.MethodsThe study population consisted of patients with RVO and central macular thickness <300 μm. For each subject, measurements were performed twice with a 5-minute interval. The intraclass correlation coefficient (ICC) and coefficient of variation (CV) were calculated to analyze the repeatability of results obtained with the OCTA device. To identify factors related to repeatability, we performed Pearson correlation analyses based on the CV of potential factors.ResultsA total of 48 eyes were included in the study. The ICCs of the VDs in superficial capillary plexus (SCP) and the deep capillary plexus (DCP) were 0.748 and 0.665, respectively, and the CVs of the VDs in SCP and DCP were 9.1% and 12.6%, respectively. The ICCs associated with the FAZ of the superficial layer (SFAZ) and that of the deep layer (DFAZ) were 0.965 and 0.956, respectively, and the CV of the SFAZ and DFAZ were 8.8% and 9.7%, respectively. From Pearson correlation analyses, OCTA quality was significantly correlated with the CV of the VDs of SCP and DCP. However, there were no variables that were significantly correlated with the CV of SFAZ and DFAZ, including OCTA quality.ConclusionsVD measurements in the SCP layer using OCTA exhibited good repeatability, and VD measurements in the DCP layer exhibited relatively low repeatability compared to that of SCP layer measurements in patients with RVO without macular edema after treatment with bevacizumab. Manual measurement of the FAZ area in both SCP and DCP layers resulted in good repeatability. In addition, the repeatability of VD measurements in SCP and DCP layers was correlated with OCTA image quality.

OCT angiography metrics predict intradialytic hypotension episodes in chronic hemodialysis patients: a pilot, prospective study

In chronic hemodialysis (HD) patients, intradialytic hypotension (IDH) is a complication that increases mortality risk. We run a pilot study to analyzing possible relationships between optical coherence tomography angiography (OCT-A) metrics and IDH with the aim of evaluating if OCT-A could represent a useful tool to stratify the hypotensive risk in dialysis patients. A total of 35 eyes (35 patients) were analyzed. OCT-A was performed before and after a single dialysis session. We performed OCT-A 3 × 3 mm and 6 × 6 mm scanning area focused on the fovea centralis. Patients were then followed up to 30 days (10 HD sessions) and a total of 73 IDHs were recorded, with 12 patients (60%) experiencing at least one IDH. Different OCT-A parameters were reduced after dialysis: central choroid thickness (CCT), 6 × 6 mm foveal whole vessel density (VD) of superficial capillary plexus (SPC) and 6 × 6 mm foveal VD of deep capillary plexus (DCP). At logistic regression analysis, IDH was positively associated with baseline foveal VD of SCP and DCP, while an inverse association was found with the choroid. In Kaplan–Meier analyses of patients categorized according to the ROC-derived optimal thresholds, CCT, the 3 × 3 foveal VD of SCP, the 3 × 3 mm and 6 × 6 mm foveal VD of DCP and the 6 × 6 mm foveal VD of SCP were strongly associated with a higher risk of IDH over the 30-days follow-up. In HD patients, a single OCT-A measurement may represent a non-invasive, rapid tool to evaluate the compliance of vascular bed to HD stress and to stratify the risk of IDH in the short term.

Quantitative Optical Coherence Tomography Angiography (OCTA) Parameters in a Black Diabetic Population and Correlations with Systemic Diseases.

This is a cross-sectional, prospective study of a population of black diabetic participants without diabetic retinopathy aimed to investigate optical coherence tomography angiography (OCTA) characteristics and correlations with systemic diseases in this population. These parameters could serve as novel biomarkers for microvascular complications; especially in black populations which are more vulnerable to diabetic microvascular complications. Linear mixed models were used to obtain OCTA mean values ± standard deviation and analyze statistical correlations to systemic diseases. Variables showing significance on univariate mixed model analysis were further analyzed with multivariate mixed models. 92 eyes of 52 black adult subjects were included. After multivariate analysis; signal strength intensity (SSI) and heart disease had statistical correlations to superficial capillary plexus vessel density in our population. SSI and smoking status had statistical correlations to deep capillary plexus vessel density in a univariate analysis that persisted in part of the imaging subset in a multivariate analysis. Hyperlipidemia; hypertension; smoking status and pack-years; diabetes duration; creatinine; glomerular filtration rate; total cholesterol; hemoglobin A1C; and albumin-to-creatinine ratio were not significantly associated with any OCTA measurement in multivariate analysis. Our findings suggest that OCTA measures may serve as valuable biomarkers to track systemic vascular functioning in diabetes mellitus in black patients.

Retinal microvasculature impairments in patients with coronary artery disease: An optical coherence tomography angiography study.

To investigate the association between retinal microvasculature and the presence and severity of coronary artery disease (CAD) using optical coherence tomography angiography (OCTA). The cross-sectional study was conducted in Guangdong Provincial People's Hospital, China. Retinal microvasculature parameters were measured by OCTA of the optic disc, including the vessel density (VD) and retinal nerve fibre thickness of the radial peripapillary capillary. In terms of the entire macula, VD of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and foveal density (FD-300) were included. The Gensini score was used to evaluate the severity of coronary artery obstructive lesions in CAD patients. A total of 410 participants (270 CAD patients and 140 controls) were included. Overall, participants showed significantly greater odds of having CAD in the lower versus higher VD for mean SCP, OR = 2.33 (95% CI 1.49-3.65); in the parafoveal SCP, OR = 2.68 (95% CI 1.70-4.23); and in the perifoveal SCP, OR = 2.36 (95% CI 1.49-3.72). Additionally, participants showed significantly greater odds of having CAD in the lower versus higher VD for mean DCP, OR = 4.04 (95% CI 2.53-6.45); in the parafoveal DCP, OR = 4.08 (95% CI 2.54-6.55); and in the perifoveal DCP, OR = 3.88 (95% CI 2.43-6.19). Among CAD patients, lower VD of DCP was associated with significantly greater adjusted Gensini scores (p = 0.004 for mean DCP; p = 0.035 for parafoveal DCP; p = 0.006 for perifoveal DCP). SCP and DCP were found to be associated with the presence of CAD among the whole population, while DCP was found to be associated with Gensini scores in CAD patients. Retinal microvasculature was associated with the presence and severity of coronary artery stenosis in CAD patients.

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

ABSTRACT 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.

Evaluation of vessel density in disorganization of retinal inner layers after resolved diabetic macular edema using optical coherence tomography angiography.

PurposeTo evaluate the retinal vessel density (VD) in the macular region and the foveal avascular zone (FAZ) area using optical coherence tomography angiography (OCTA) in patients with and without disorganization of retinal inner layers (DRILs) after resolution of diabetic macular edema.MethodsThirty-seven eyes of 37 DRIL patients (mean age 63 ± 13.97 years), 30 eyes of 30 no DRIL patients and 35 eyes of 35 controls were enrolled in this study. We evaluated the VD in the macular region of superficial capillary plexus (SCP), deep capillary plexus (DCP) and FAZ area.ResultsDRIL and no DRIL groups showed decreased VD in SCP and DCP (p<0.05) and a larger FAZ area (p<0.001) compared to controls. However, DRIL patients revealed a statistically significant reduction in VD of SCP (p = 0.041) and a greater FAZ area (p<0.001) with respect to no DRIL patients. We found a significant negative correlation between the VD of the foveal SCP (r = -0.414, p = 0.011), foveal DCP (r = -0.358, p = 0.025) and best corrected visual acuity (BCVA) in DRIL group. Moreover there was a significant positive correlation between the FAZ area (r = 0.425, p = 0.034) and BCVA. Therefore, in presence of DRILs lower VD values of SCP and DCP and a larger FAZ area correlated with a worse visual acuity. In no DRILs group, there was a significant negative correlation between the VD of the foveal DCP and BCVA.ConclusionOCTA highlights the role of retinal vascular ischemia in the pathogenesis of DRILs. This parameter could represent an important functional predictive factor in diabetic patients.

Evaluation of retinal vessel density and foveal avascular zone measurements in patients with obstructive sleep apnea syndrome.

To compare retinal capillary plexus vessel densities, choroidal thickness, optic disc vessel densities and foveal avascular zone measurements between normal subjects and subjects with obstructive sleep apnea syndrome (OSAS) using spectral-domain OCT angiography (OCTA). Forty eyes of patients with overall OSAS, 20 eyes of patients with mild-moderate OSAS, 20 eyes of patients with severe OSAS on polysomnography and 21 controls were evaluated with the RTVue-XR Avanti OCTA (Optovue, Inc., Fremont, CA). Superficial and deep retinal capillary plexus vessel densities, choroidal thickness and foveal avascular zone (FAZ) parameters (area, diameter, acircularity index of the FAZ, foveal density-300) were measured for all subjects. Superficial capillary plexus vessel densities of the groups were similar. Deep capillary plexus (DCP) vessel densities of all three OSAS groups decreased in the parafoveal region (< 0.001). In the perifoveal region, DCP vessel densities were decreased in the Overall OSAS group (p = 0.023) and in the Severe OSAS group (p = 0.021), whereas it was similar in the Mild-moderate OSAS group. Choroidal thickness decreased in all three OSAS groups (p < 0.001). All FAZ measurements and foveal density-300 measurements were similar compared to the control group. Our findings indicate that in severe OSAS patients, deep parafoveal, perifoveal vascular densities decrease and the choroid layer becomes thinner. When evaluating a patient with OSAS, it should be kept in mind that there may be eye involvement due to the disease.

Effect of blunt ocular trauma on retinal microvasculature: An optical coherence tomography angiography study.

To evaluate the retinal vascular changes and foveal avascular zone area in patients with unilateral blunt ocular trauma using optical coherence tomography angiography. This retrospective study consisted of 50 traumatized and 50 contralateral sound eyes of the patients with blunt ocular trauma. The foveal avascular zone area, choriocapillaris flow area, foveal, parafoveal, and perifoveal vessel densities in both superficial capillary plexus and deep capillary plexus and central macular thickness were evaluated. There were no significant differences between traumatized and sound eyes in the foveal avascular zone area (p:0.36), choriocapillaris flow area (p:0.43), central macular thickness (p:0.67), and in vessel densities of superficial capillary plexus over all regions (p > 0.05 for all). However, the vessel densities of deep capillary plexus were significantly lower in traumatized eyes (p < 0.05 for all). Optical coherence tomography angiography demonstrated a significant decrease in retinal deep capillary plexus vessel density of the eyes effected by blunt ocular trauma, even with no evident findings on fundus examination or structural spectral domain-optical coherence tomography changes.

Evaluation of Peripapillary and Macular Vascular Flow Changes with OCT-A in Patients with Superficial Optic Disk Drusen.

ObjectivesThe purpose of this study was to compare the peripapillary and macular vascular flow changes between healthy adults and adult patients with superficial optic disk drusen (ODD), as evaluated by optical coherence tomography angiography (OCT-A).MethodsIn this retrospective study, 44 eyes of 22 patients with superficial ODD followed-up in our neuro-ophthalmology unit and 54 eyes of 27 healthy individuals admitted to our clinic for routine ophthalmological examination were included in the study. The superior, inferior, nasal, and temporal radial peripapillary capillary plexus (RPC) vessel density (VD) values; superior, inferior, nasal, and temporal parafoveal and foveal region superficial capillary plexus (SCP) and deep capillary plexus (DCP) VD values; and choriocapillaris flow (CCF) area and foveal avascular zone area were evaluated by OCT-A.ResultsThere was no statistically significant difference between groups in terms of age and sex. While there was a significant decrease in the temporal RPC VD values in cases with ODD (p=0.02), no significant difference was observed in other quadrants. No significant differences in either parafoveal zone four quadrant, foveal SCP and DCP VD values, or foveal avascular zone measurements were found between groups, while CCF area values were significantly higher in the study group (p=0.012).ConclusionCompared to healthy controls, our results showed a decrease in the RPC temporal quadrant VD values, and an increase in CCF area in cases with superficial ODD. To evaluate the effects of ODD on optic nerve head and macular perfusion, and to understand its underlying mechanisms and secondary complications, longer follow-up studies with larger case series are needed.

The Retinal Vessel Density as a New Vascular Biomarker in Multisystem Involvement in Fabry Disease: An Optical Coherence Tomography Angiography Study.

In this study, we evaluated the possible relationship between the changes in retinal vessel density (VD) by optical coherence tomography angiography (OCTA) and the vascular alterations involving renal, cardiovascular and central nervous systems in patients affected by Fabry disease (FD). In 50 FD patients, the retinal superficial capillary plexus (SCP) and deep capillary plexus (DCP) in macular region were evaluated by OCTA examination. The patients also underwent a brain magnetic resonance imaging scan, renal and echocardiographic examinations with quantification of systolic pulmonary arterial pressure (PAPs) and left atrial volume index (LAVi). The VD of SCP and DCP was inversely related with E/e’ ratio, LAVi, interventricular septal thickness, global longitudinal strain (GLS) and PAPs (p < 0.05). No relationship was found, with a multivariate analysis, between OCTA parameters and kidney function and neuroradiological signs of central nervous system involvement. OCTA could be a new vascular biomarker in FD, revealing a strong correlation between retinal capillary damage and myocardial impairment, possibly preceding both renal dysfunction and cerebrovascular involvement.

Influences of Hypomagnesemia on Optic Nerve and Retinal Vascular Structure Determined Using Optical Coherence Tomography (OCT) Angiography.

ABSTRACT Purpose: To evaluate the effects of low blood magnesium levels on the optic nerve, retina, and retinal vascular structure. Methods: This observational and cross-sectional study was conducted between June 2019 and May 2020 with participants aged 20–39 years, who had a visual acuity of ≥20/20, the axial length of 22–24.5 mm, refractive defect spherical equivalent of ≤±3D, and intraocular pressure of ≤21 mm Hg. All participants had a complaint of twitching in their eyes. The participants with normal serum magnesium levels constituted the control group, and patients with hypomagnesemia constituted the patient group. Updated AngioScan software (Navis ver. 1.8.0.) of Nidek’s RS-3000 Advance system was used to analyze the spectral domain-optical coherence tomography (SD-OCT) and optical coherence tomography-angiography (OCT-A) images. Results: A total of 100 right eyes of 100 individuals was included in the study. The mean retinal nerve fiber layer (RNFL) thickness was 108.52 ± 12.46 μm in the control group, and 97.3 ± 9.7 μm in the hypomagnesemia group (P < .001). In the control group, the global superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel densities (VDs) were 41.92 ± 2.29, and 37.54 ± 3.83, respectively. In the patient group, the global SCP and DCP VDs were 37.66 ± 3.14, and 32.95 ± 5.57, respectively. The SCP and DCP VD percentages were significantly lower in the patient group. The mean foveal avascular zone (FAZ) area, perimeter and circularity index (CI) were 0.32 ± 0.13 mm2, 2.89 ± 0.59 mm, and 0.52 ± 0.09, respectively, for the control group and 0.38 ± 0.11 mm2, 2.99 ± 0.64 mm, and 0.38 ± 0.1, respectively, for the patient group. The FAZ area and perimeter were significantly higher (P = .013 and P = .001) and FAZ CI was significantly lower (P < .001) in the patients with hypomagnesemia. Conclusion: Our study revealed that OCT and OCT-A measurements may be used in the determination of the optic nerve and retinal vascular structure changes in hypomagnesemia.

Macular microvasculature differences in patients with macular hole after vitrectomy with internal limiting membrane removal or single-layered temporal inverted flap technique.

To compare the macular microvasculature differences in cases with idiopathic macular hole (MH) after vitrectomy when using internal limiting membrane (ILM) removal or temporal inverted ILM flap technique (IFT). A total of 34 patients were included, of whom 20 were treated vitrectomy with ILM removal (group 1), and 14 were treated with IFT (group 2). The OCTA (RTVue; Optovue, Fremont, CA) parameters, including foveal avascular zone (FAZ), vessel density (VD) ratios in superficial capillary plexus (SCP), and deep capillary plexus (DCP) were evaluated at baseline and 6 months follow-up. The VD measurements in DCP and inner retinal thickness (IRT) in temporal and nasal sectors were compared in subanalyses. There was no significant difference in means of post-operative BCVA and FAZ between the two groups (p = 0.943, p = 0.760). The mean VDs of the DCP was significantly decreased at 6 months postoperatively in both groups (p < 0.001, p < 0.001). The mean post-operative temporal VDs of DCP were similar in the two groups, but the mean post-operative nasal VDs of the DCP was lower in group 1 than in group 2 (p = 0.005 and p = 0.03 for parafovea and perifovea, respectively). The mean temporal IRTs were similar in the two groups, but paranasal and perinasal IRTs were significantly thinner in group 1 than in group 2 (p < 0.001, p < 0.001). The mean post-operative VDs of parafoveal and perifoveal temporal and nasal quadrants in DCP significantly and positively correlated with the IRTs. Single-layered temporal IFT causes fewer VD changes when compared to complete ILM removal, especially in the DCP.

Early vascular modifications after endoscopic endonasal pituitary surgery: The role of OCT-angiography.

PurposeThe aim of the present study is to analyze the changes in retinal vessel density (VD), using Optical Coherence Tomography Angiography (OCT-A), in patients that received endoscopic endonasal approach for the removal of an intra-suprasellar pituitary adenoma compressing optic chiasm.MethodsWe evaluated the VD in Superficial Capillary Plexus (SCP), Deep Capillary Plexus (DCP), Radial Peripapillary Capillary (RPC) and the Foveal Avascular Zone (FAZ) area in a series of fourteen patients (7 males, 7 females, mean age 56 ± 13 years), as compared to healthy controls. We also detected the structural Spectral Domain (SD)-OCT parameters: Ganglion Cell Complex (GCC), Retinal Nerve Fiber Layer (RNFL), visual field parameters (Mean Deviation, Pattern Standard Deviation) and Best Corrected Visual Acuity (BCVA). These measurements were performed prior than surgery and 48 hours after.ResultsThe patients showed a significant decrease in VD of the macular and papillary regions, a significant increase in FAZ area, a significant impairment in SD-OCT, VF parameters and BCVA respect to 14 eyes of 14 healthy controls (p<0.05), at pre-op evaluation. In patients group the VD in SCP, DCP and RPC increased after surgery respect to baseline but the difference turned to be out statistically significant only in RPC (p = 0.003). Also the BCVA (p = 0.040) and the Mean Deviation at visual field (p = 0.015) significantly improved after surgery. While there was a reduction in structural OCT parameters but it was statistically significant only in GCC (p = 0.039). A positive correlation was found between the preoperative VD of the RPC, Mean Deviation, BCVA and the postoperative Mean Deviation (r = 0.426 p = 0.027; r = 0.624 p = 0.001; r = 0.515 p = 0.006).ConclusionOCT-A allows to detect the early changes occurring within 48 hours after surgery showing that the improvement in retinal vessel density could occur before the recovery of the structural OCT parameters and can be a positive predictive factor for the functional recovery.

Evaluation of retinal vascular structure after epiretinal membrane surgery by optical coherence tomography angiography.

To evaluate the retinal vascular structure before and after the epiretinal membrane (ERM) surgery by optical coherence tomography angiography (OCTA). Twenty-two eyes with ERM (study eyes) had been evaluated by OCTA for superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density (VD) at foveal and parafoveal regions and foveal avascular zone (FAZ) before and after ERM removal surgery. Twenty-two fellow eyes were selected as control group. Preoperative VD of SCP and DCP were significantly lower in ERM eyes than in controls in both foveal and parafoveal areas (p < 0.05, for all). The difference regressed in SCP (fovea: 18.04 ± 3.1 vs 19.98 ± 18 p = 0.002 and parafovea: 47.33 ± 3.54 vs 49.71 ± 28 p = 0.001), but persisted in DCP (fovea: 17.25 ± 3.52 vs 17.57 ± 4.01 p = 0.856 and parafovea: 50.12 ± 4.35 vs 50.93 ± 3.24 p = 0.791) in study eyes, postoperatively. Superficial and deep FAZ areas were significantly smaller in study eyes than controls. Postoperatively, superficial FAZ area enlarged (0.288 ± 0.10 vs 0.307 ± 0.08 p = 0.012), whereas deep FAZ area did not (0.324 ± 0.09 vs 0.338 ± 0.07 p = 0.435). FAZ area was correlated with the best-corrected visual acuity in ERM eyes. Vascular damage in SCP and DCP was demonstrated by OCTA in eyes with ERM. ERM removal surgery mainly improves superficial changes caused by ERM. Changes in deep retinal flow may be associated with visual outcomes after ERM removal surgery.

Assessment of retinal vessel density in adult-onset foveomacular vitelliform dystrophy by optical coherence tomography angiography

To evaluate retinal thickness, area of foveal avascular zone (FAZ), flow area and flow density of choriocapillaris, vessel density of both superficial capillary plexus (SCP) and deep capillary plexus (DCP) of eyes with adult-onset foveomacular vitelliform dystrophy (AOFVD) using optical coherence tomography angiography (OCT-A) and compare the results with healthy controls. 17 eyes of 14 patients diagnosed with AOFVD and 17 eyes of 17 healthy subjects were enrolled in this study. All patients underwent a complete ophthalmological examination and a 6 x 6 mm macular OCT-A scanning. Quantiative results of retinal thickness, retinal vessel density of SCP and DCP, FAZ area, flow area and flow density of choriocapillaris were analyzed. No statistically significant differences were noted in the vessel density of the SCP, except for the parafoveal nasal sector (P = 0.048). Similarly, no statistically significant differences were observed in the vessel density of the DCP, except for the parafoveal (P = 0.037) and the parafoveal temporal (P = 0.048) sectors. The choriocapillaris flow area and the flow density were significantly lower in the patients with AOFVD than in the healthy controls (P = 0.001 for both). The mean FAZ area and the retinal thickness measurements were comparable in both groups. Patients with AOFVD show vascular abnormalities that can be detected with OCT-A. OCT-A, as a noninvasive imaging modality, could provide a new perspective for understanding the pathophysiology of AOFVD and could also be useful in the follow-up of these patients and in the management of the disease progression.