Macular Perfusion Research Articles

Analysis of macular blood flow changes in thyroid associated ophthalmopathy

BackgroundTo evaluate the changes in macular superficial retinal vessel density and their relation with visual acuity in thyroid-associated ophthalmopathy (TAO) patients with different severity.MethodsThis cross-sectional observational study included 70 TAO patients and 70 healthy controls. Only data from the right eyes were analyzed. TAO patients were divided into 7 subgroups according to the NOSPECS score. Foveal avascular zone (FAZ), vascular density (VD), and perfusion density (PD) of macular 1 mm diameter and 6 mm diameter areas were measured by optical coherence tomography angiography (OCTA).ResultsIn TAO patients, significant increases were found in macular and foveal vascular densities (FVD) and perfusion densities (FPD) while a significant decrease was found in the FAZ area when compared with the control group (p < 0.05). Spearman correlation analysis and multiple linear regression analysis showed that TAO severity grade was negatively correlated with FVD (β = -1.150, p = 0.032), FPD (β = -0.024, p = 0.042), MVD (β = -0.583, p = 0.020) and MPD (β = -0.011, p = 0.010). Clinical activity score (CAS) score showed positive correlation with FVD (β = 0.794, p = 0.035) and FPD(β = 0.017, p = 0.041). FVD (β = -0.009, p = 0.033), MVD(β = -0.034, p < 0.001), FPD(β = -0.416, p = 0.039) and MPD(β = -2.428, p < 0.001) all showed negative correlation with best corrected visual acuity (BCVA).ConclusionsThere was an overall increase in superficial macular blood flow in TAO patients compared with healthy controls and the blood flow decreased as TAO got worse. Superficial macular flow density was negatively correlated with BCVA.

Macular and peripapillary microvascular changes in open angle glaucoma and ocular hypertension: A longitudinal study using optical coherence tomography angiography (OCT‐A)

AbstractPurpose: To investigate prospectively macular and peripapillary microvascular changes in patients with glaucoma and ocular hypertension.Methods: A 12‐month prospective longitudinal study was performed with 124 open‐angle‐glaucoma‐eyes (GE), 111 ocular‐hypertension‐eyes (OHE) and 98 gender and age matched control‐eyes (CE). Glaucomatous progression was defined as a decrease of ≥5 μm in average or ≥7 μm in a sector of RNFL thickness. OMAG OCT microangiography (Angioplex, HD OCT, Cirrus 5000, Zeiss) was used to analyse optic disc and macular regions. The statistical analysis was performed using Mann–Whitney‐Test with the SPSS version 23.0 statistical package (SPSS Inc., IL).Results: Among OHE and GE groups, 21.7% of eyes showed progression, being the decrease of Peripapillary Flux Index (PFI), Macular Vessel Density (MVD) and Macular Capillary Perfusion Density (MPD) greater (−0.0067; −0.696 mm/mm2 and −1.56%) compared to non‐progressive eyes (+0.0038; 0.527 mm/mm2 and 1.55%) being the nasal and inferior sectors for PFI, and the superior and temporal sectors for both MVD and MPD, the ones that showed greater differences [p = 0.015 and p &lt; 0.001 for the last two]. Furthermore, Peripapillary Perfusion Density (PPD) showed non‐significant greater decrease (−0.347) compared to non‐progressive eyes (−0.324) [p = 0.775]. Characteristics as increased vertical cup to disc ratio (CDV) (0.64 vs. 0.57), elevated intraocular pressure (IOP) (18.25 vs. 15.40 mmHg), thinner central corneal thickness (CCT) (520.18 vs. 541.67 μm) and lower ocular perfusion pressure (OPP) (47.81 vs. 48.95 mmHg) were significantly different in those progressive OHE and GE [p &lt; 0.05 for all]. Nevertheless, minimum ganglion cell layer thickness (GCLM) was only significantly lower in progressive GE (58.51 vs. 73.98 μm) [p = 0.036].Conclusions: Data showed that when glaucomatous progression took place, stronger microvascular changes occurred in the macular and peripapillary areas, as greater decrease of MVD, MPD and PFI, especially in superior and temporal sectors for the macular area, and in nasal and inferior sectors for the peripapillary area. Nevertheless, further research with larger population and larger follow‐up is needed to obtain stronger results.

Long‐term follow up of macular perfusion evaluated by optical coherence tomography angiography after rhegmatogenous retinal detachment surgery

AbstractPurpose: To investigate macular microvascular changes using OCTA in patients one‐year after a successful RDD surgery.Methods: Cross‐sectional study including RRD treated using PPV ± SB and SF6 tamponade. Eyes were divided related to their macular status previous surgery and depending on the surgical technique used. All the subjects underwent complete ophthalmological examinations including a 3x3 OCTA protocol using DRI‐Triton swept source (SS)‐OCT with a minimum 12 months follow‐up after the surgery. Retinal capillary plexuses and CC vessel density (VD) were studied. FAZ area and diameters were measured. Results were compared with the unaffected contralateral eye.Results: Sixty eyes of 57 patients with RRD were included. Mean age was 59.14 ± 9.52 years. PPV was performed in 68.3% of the eyes, associated to SB in 31.6%. The macula was affected in 38.3% of the eyes and unaffected in 61.7%. RRD macula‐off had lower VA than the contralateral eyes. No differences were observed in VD between RRD macula‐on eyes regardless of the surgical technique performed. However, one year after surgery, we observed a significantly increased VD in the central area of macula‐off RRD eyes treated with PPV + SB in both retinal plexuses and in the SCP of RRD treated with PPV compared to the fellow eyes. All the macula‐off treated eyes had a diminished VD for both SCP and DCP in the superior quadrant and in PPV + SB we also found a diminution in the inferior quadrant for the SCP. In the inferior quadrant, we only found a diminution in the SCP flow in macula‐off treated with PPV + SB. We found changes at the CC level in the temporal quadrant of the macular‐off treated with PPV + SB. We did not observe differences in FAZ area between any groups. FAZ horizontal and vertical diameters were statistically smaller in patients with macula‐off RRD.Conclusion: Macular vascularity remains almost unchanged in patients one year after successful RRD surgery, despite the surgical technique (VPP vs VPP + SB). Vascular changes are not remarkable in neither macula‐on not macula‐off RDD. We found an increase in VD in the central area of the retinal capillary plexus in patients after macula‐off RDD associated to a diminution in VD of both superior and inferior quadrants of the retinal plexuses suggesting changes in vascularization after macula‐off RRD surgery.

Changes in Macular Perfusion afterTrabeculotomy Operation in Primary Open Angle Glaucoma by Optical Coherence Tomography Angiography

Changes in Macular Perfusion afterTrabeculotomy Operation in Primary Open Angle Glaucoma by Optical Coherence Tomography Angiography

A moderate dosage of coffee causes acute retinal capillary perfusion decrease in healthy young individuals

Aim:Caffeinated beverages are very popular across populations and cultures, but quantitative evidence of the acute effects of moderate coffee doses on retinal perfusion is sparse and contradicting. Thus, the aim of this randomized, cross-over and parallel-group design study was to investigate whether moderate consumption of coffee alters macular retinal capillary perfusion in young healthy individuals.Methods:Twenty-seven young healthy individuals were recruited for this study. Acute changes in retinal microvasculature were assessed using spectral-domain optical coherence tomography angiography (SD-OCTA) at baseline, 0.5 h, and 2 h after intake of coffee, or water. Meanwhile, cerebral blood flow (CBF) and retina-choroid blood flow were evaluated in a parallel-group design (4 participants each in coffee or water group) using magnetic resonance imaging (MRI) with pseudo-continuous arterial spin labeling sequences.Results:Two hours after coffee intake, blood caffeine concentration increased from 0 to 5.05 ± 1.36 µg/mL. Coffee caused a significant decrease in retinal vessel diameter index (VDI) (19.05 ± 0.24 versus [vs] 19.13 ± 0.26; p < 0.001) and CBF in the frontal lobe (77.47 ± 15.21 mL/100 mL/min vs. 84.13 ± 15.55 mL/100 mL/min; p < 0.05) 2 h after intake. However, it significantly increased retina-choroid blood flow after 0.5 and 2 h (163.18 ± 61.07 mL/100 mL/min vs. 132.68 ± 70.47 mL/100 mL/min, p < 0.001, and 161.21 ± 47.95 vs. 132.68 ± 70.47; p < 0.001, respectively).Conclusion:This is the first study to demonstrate the acute effects of daily dose coffee consumption on retinal capillary perfusion using SD-OCTA combinate with blood flow MRI. The findings imply that although moderate coffee intake caused a significant increase in retina-choroid blood flow, there was a significant acute decrease both in macular retinal capillary perfusion and CBF.

Long-Term Follow-Up of Macular Perfusion Evaluated by Optical Coherence Tomography Angiography after Rhegmatogenous Retinal Detachment Surgery.

The goal of this study was to investigate macular microvascular changes using optical coherence tomography angiography (OCTA) at one year after successful rhegmatogenous retinal detachment (RRD) surgery. We performed a cross-section study including RRD treated by pars plana vitrectomy (PPV) with or without scleral buckling and SF6 tamponade. After 12 months, DRI-Triton SS-OCTA was performed. Superficial and deep retinal capillary plexuses (SCP and DCP), choriocapillaris (CC) vessel density (VD), and foveal avascular zone (FAZ) morphology were analyzed. Results were compared with the unaffected contralateral eye. Sixty eyes were included. We observed an increase in VD in the central area of both the SCP and DCP in macula-off eyes treated with PPV + SB and in the SCP of macula-off eyes treated with PPV. Macula-off eyes had a diminished VD for both plexuses in the superior quadrant and in the SCP inferior quadrant in those treated with PPV + SB. The CC flow was diminished in the temporal quadrant of macular-off eyes treated with PPV + SB. Healthy eyes presented higher diameter values than macula-off eyes treated with PPV + SB. FAZ horizontal and vertical diameters were smaller in patients with macula-off RRD vs. macula-on RRD and control groups. Macular vascularity remains almost unchanged one year after successful RRD surgery, irrespective of the surgical technique or prior macular status.

Three Monthly Injections Versus One Initial Injection of Ranibizumab for the Treatment of Macular Edema Secondary to Branch Retinal Vein Occlusion: 12-Month Results of a Prospective Randomized Study.

To compare three monthly injections versus one initial injection of intravitreal ranibizumab (IVR) followed by pro re nata (PRN) dosing to treat macular edema secondary to branch retinal vein occlusion (BRVO). Seventy-four patients were randomized (1:1) to the 3+ PRN or 1+ PRN groups. Patients underwent monthly evaluations and additional IVR injections were administered if the retreatment criteria were met. The functional and anatomical outcomes were recorded. The factors associated with the improvement in best-corrected visual acuity (BCVA) were analyzed. Sixty-nine patients (93.2%) completed the study. At 12months, the mean gain in BCVA was 12.9 letters in the 3 + PRN group and 14.3 letters in the 1 + PRN group, which was not significant (P = 0.59). The mean reduction in central macular thickness was 297.8μm in the 3 + PRN group and 300.2μm in the 1 + PRN group (P = 0.96). The macular vascular density changes of the superficial and deep capillary plexuses were not significantly different between the two groups (P = 0.99 and 0.70, respectively). The mean number of IVR injections was 5.0 in the 3 + PRN group and 4.2 in the 1 + PRN group (P = 0.17). The incidence of retinal neovascularization was similar in both groups (P = 0.67). The baseline BCVA, but not the treatment regimen, was significantly associated with the change in BCVA (P < 0.01). Significant gains in BCVA and maintenance of macular perfusion were achieved in BRVO eyes treated with the 3 + PRN or 1 + PRN regimens. Baseline BCVA was a prognostic factor for the visual improvement. A prospective randomized controlled trial to compare the 1 + PRN and 3 + PRN regimen in the treatment of macular edema secondary to branch retinal vein occlusion (ChiCTR2000038086).

Long-Term Functional Hyperemia after Uncomplicated Phacoemulsification: Benefits beyond Restoring Vision.

The purpose of the study was to investigate the long-term effects of uncomplicated phacoemulsification on macular perfusion using optical coherence tomography angiography (OCTA) in healthy aging subjects. OCTA was performed before phacoemulsification and 1 week, 1 month, 3 months, and 6 months after. Superficial vascular complex (formed of nerve fiber layer vascular plexus and superficial vascular plexus), deep vascular complex (formed of intermediate capillary plexus and deep capillary plexus), as well as choriocapillaris (CC) and large choroidal blood vessels were recorded. Significant changes of vascular parameters in 95 eyes of 95 patients reached plateau 1 week after surgery and remained stable up to 6 months, occurring in all retinal layers but not in choroid and CC. Statistically significant increases in retinal vessels area, vessels percentage area, total number of junctions, junctions density, and total and average vessels length were found, followed by the total number of end points and mean lacunarity decline, proving an increase in blood supply. The study confirmed that uncomplicated phacoemulsification leads to a long-term increase in macular retinal perfusion. The results might ease the decision regarding timing for cataract surgery as long-term perfusion benefits can be achieved. Furthermore, study results provide a normative database of retinal and choroidal vasculature in healthy aging patients.

Reproducibility of macular perfusion parameters in non-proliferative diabetic retinopathy patients by two different OCTA sweep modes.

To assess the reproducibility of macular perfusion parameters in non-proliferative diabetic retinopathy (NPDR) patients measured by different examiners and two different sweep modes of optical coherence tomography angiography (OCTA). Ninety-eight (98 eyes) patients with NPDR were included in this study. All participates were performed three times using Cirrus OCTA with Angiography 3×3 mm2 and 6×6 mm2 sweep mode by two examiners. The macular foveal avascular zone (FAZ) and vessel density (VD) in the superficial retinal layer (SRL) were measured. The reproducibility of the measurements was evaluated with intraclass correlation coefficients (ICC) and coefficient of variation (CoV). The intra-mode ICCs of Angiography 3×3 mm2 and 6×6 mm2 sweep mode were 0.957 to 0.959 and 0.964 to 0.977, respectively; and the inter-mode ICCs were 0.962 to 0.970. The intra-examiner ICCs of macular perfusion parameters were >0.950; and the inter-examiner ICCs were 0.928 to 0.969. All CoVs were <1.0%. Cirrus OCTA can measure macular perfusion parameters in NPDR patients with excellent reproducibility. The measurements of FAZ and VD in the SRL determined by Angiography 3×3 mm2 and 6×6 mm2 sweep mode are highly consistent and both sweep modes are suitable for macular perfusion parameters measurement.

In vivo assessment of associations between photoreceptors structure and macular perfusion in type 1 diabetes

PurposeTo explore the potential relationships between macular vascular network and different adaptive optics (AO) metrics in patients with type 1 diabetes mellitus (DM1) with no signs (NoDR) or mild non-proliferative...

Multi-Center Repeatability of Macular Capillary Perfusion Density Using Optical Coherence Tomography Angiography.

Background/AimsThis study was to determine the test–retest repeatability in quantifying macular capillary perfusion density (CPD, expressed as fractal dimension) using optical coherence tomography angiography (OCTA) in a multi-center setting.MethodsOCTA data were obtained in self-reported healthy subjects from Bascom Palmer Eye Institute at the University of Miami (UM, N = 18) and the University of Pennsylvania (UPenn, N = 22). The right eye of each subject was imaged twice at the first visit and then again at an interval of one week to assess intra-visit and inter-visit repeatability. The macular area of the OCTA-derived capillary perfusion density (OCTA-CPD) was analyzed by custom-made image processing and fractal analysis software. Fractal analysis was performed on the skeletonized microvascular network to yield OCTA-CPD by box-counting to the fractal dimension (Dbox) in the superficial vascular plexus (SVP). Repeatability was assessed by three measures: within-subject standard deviation (Sw), coefficient of variation (CoV) of repeated measures, and intraclass correlation coefficient (ICC).ResultsOCTA-CPD from both sites (UM and UPENN) showed good to excellent intra-visit repeatability, as demonstrated by the Sw ≤0.004, CoVs ≤0.23%, and ICCs ≥0.61. Similarly, both sites had good to excellent inter-visit repeatability, as shown by the Sw ≤0.005, CoVs ≤0.28%, and ICCs ≥0.61. The Bland-Altman plots of the intra-visit and inter-visit measurements showed excellent agreements between the paired measurements with minimal biases.ConclusionOur data showed that comparable high repeatability of OCTA-CPD can be achieved in both research sites using the same device, scan protocol, and image analysis.

Optical coherence tomography reveals retinal thinning in schizophrenia spectrum disorders

BackgroundSchizophrenia spectrum disorders (SSDs) are presumed to be associated with retinal thinning. However, evidence is lacking as to whether these retinal alterations reflect a disease-specific process or are rather a consequence of comorbid diseases or concomitant microvascular impairment.MethodsThe study included 126 eyes of 65 patients with SSDs and 143 eyes of 72 healthy controls. We examined macula and optic disc measures by optical coherence tomography (OCT) and OCT angiography (OCT-A). Additive mixed models were used to assess the impact of SSDs on retinal thickness and perfusion and to explore the association of retinal and clinical disease-related parameters by controlling for several ocular and systemic covariates (age, sex, spherical equivalent, intraocular pressure, body mass index, diabetes, hypertension, smoking status, and OCT signal strength).ResultsOCT revealed significantly lower parafoveal macular, macular ganglion cell–inner plexiform layer (GCIPL), and macular retinal nerve fiber layer (RNFL) thickness and thinner mean and superior peripapillary RNFL in SSDs. In contrast, the applied OCT-A investigations, which included macular and peripapillary perfusion density, macular vessel density, and size of the foveal avascular zone, did not reveal any significant between-group differences. Finally, a longer duration of illness and higher chlorpromazine equivalent doses were associated with lower parafoveal macular and macular RNFL thickness.ConclusionsThis study strengthens the evidence for disease-related retinal thinning in SSDs.

Analysis of Microvascular Abnormalities in Obesity: A Comparative Study with Healthy Subjects Using Swept Source Optical Coherence Tomography Angiography and Adaptive Optics

Purpose: The aim of this study was to analyze retinal microvasculature in obese subjects as compared to a normal-weight population. Methods: In this case-control observational study, swept-source optical coherence tomography angiography (SS-OCTA) and adaptive optics (AO) were performed in eyes of nondiabetic, nonhypertensive, obese patients and in healthy controls. AO was used to calculate the wall-to-lumen ratio (WLR). The foveal avascular zone (FAZ), the macular vessel density, and the macular perfusion density of the superficial and deep capillary plexuses were analyzed in 6 × 6 mm macular OCTA cubes. SS-OCTA was also used to measure the choroidal thickness, the retinal nerve fiber layer (RNFL), and the vascular density of the retinal peripapillary capillary plexus. Results: The obese group included 45 eyes (24 patients), and the control group included 46 eyes (23 subjects). The central macular density and perfusion density were significantly lower in obese patients compared to controls, in the deep retinal layer (0.28 [0.01–0.69] vs. 1.24 [0.82–1.66], p = 0.006 and 0.006 [0.001–0.015] vs. 0.025 [0.016–0.034], p = 0.01), respectively, after adjustment for systolic blood pressure. No differences were found in macular vascular density in other areas, FAZ (circularity, area, perimeter), choroidal thickness, RNFL. WLR was increased in obese patients (0.252 [0.246–0.259] vs. 0.239 [0.231–0.245] in controls, p = 0.016). Conclusion: Obesity was associated with retinal microvascular changes regardless of the presence of diabetes and hypertension. Our findings suggest the presence of infraclinical microvascular changes directly associated with obesity, which can be identified noninvasively through retinal imaging.

Effects of Exercise on Optic Nerve and Macular Perfusion in Glaucoma and Normal Subjects.

Using optical coherence tomography angiography, we found an increase in the blood flow in regional macular without significant changes in the optic disk in patients with glaucoma after a moderate exercise regime. To investigate the effect of moderate exercise on optic nerve and macular perfusion in glaucoma patients. Overall, 25 eyes of 25 patients with primary open angle glaucoma and 22 eyes of 22 normal subjects were included in the glaucoma and control groups, respectively. Foveal avascular zone parameters, whole and regional vessel density (VD) in the superficial layer of macula, VDs in the radial peripapillary capillary layer of the optic nerve head, intraocular pressure, and cardiovascular parameters were measured using optical coherence tomography angiography before, immediately after, and 30 minutes after a 20-minute run at moderate speed. In the glaucoma group, macular superficial VD of the whole image, parafovea, and superior and nasal regions were higher after 30 minutes of rest (44.049±5.704, 47.238±5.741, 48.692±6.648, and 47.852±5.078) than immediately after exercise (43.229±5.867, 46.334±5.984, 47.840±6.895, 46.793±5.238, P <0.05). The VD in the temporal and nasal regions was higher 30 minutes after exercise (45.105±5.512 and 47.852±5.078) than before exercise (44.265±5.803 and 46.750±5.639, P <0.05). The intraocular pressure decreased immediately after exercise (14.20±2.51 and 14.51±2.96mmHg for glaucoma and controls, respectively) but was restored after 30 minutes of rest (15.84±3.57mmHg for glaucoma and 16.50±2.25mmHg for controls) in both groups ( P <0.001). Cardiovascular parameters were similar in both groups. Moderate physical exercise for 20 minutes increased blood flow in the macula region without significant change to the optic nerve and lowered intraocular pressure in glaucoma and normal subjects. The benefit of these findings to glaucoma patients needs further study.

Impact of Silicone Oil Removal on Macular Perfusion.

(1) Background: Silicone oil (SO) can be used as an endotamponade during vitreoretinal surgery for retinal detachment. There is emerging evidence that SO filling of the vitreous cavity and its removal may impact macular perfusion. So far, studies have not focused on choroidal sublayer perfusion, yet. (2) Methods: Optical coherence tomography angiography was applied in 19 patients with SO endotamponade before and four weeks after removal of SO. (3) Results: Perfusion of choriocapillaris increased significantly after SO removal, while perfusion of Haller’s and Sattler’s layer decreased significantly. (4) Conclusions: Removal of SO impacts choroidal perfusion and leads to a perfusion shift within choroidal sublayers. This study underlines that it is worth to conduct larger prospective studies that evaluate the choroidal perfusion and its functional implications in more detail.

Microvascular assessment of macula, choroid, and optic disk in children with unilateral amblyopia using OCT angiography.

To investigate the microvascular changes of macula, choroid, and optic disk in children with unilateral amblyopia. This prospective cross-sectional study involved 39 unilateral amblyopic children and 39 age- and sex-matched heathy participants who served as control. Vessel densities of the superficial and deep capillary plexuses (SCP and DCP), foveal avascular zone (FAZ) area, macular thickness, optic disk vessel density, retinal nerve fiber layer (RNFL) thickness, choriocapillaris vessel density, and subfoveal choroidal thickness were evaluated by OCT angiography (OCTA). Meanwhile, the correlations of microvascular perfusion and structural changes of macula, choroid, and optic disk were analyzed. The vessel density of SCP and DCP in the whole macula in the amblyopic group was significantly lower than that in the control group after adjusting for age, axial length, and spherical equivalents (all P < 0.05). FAZ area, macular thickness, RNFL thickness, and the optic disk vessel density were not statistically different between the amblyopic group and the control group (all P > 0.05). Subfoveal choroidal thickness of amblyopic eyes was significantly higher than that of control eyes(P = 0.032). Choriocapillaris flow void (FV) in the amblyopic group was greater than that in the control group (P = 0.013). Significant differences were observed between the fellow eyes and the control eyes in choriocapillaris FV and subfoveal choroidal thickness (P = 0.011 and P = 0.042, respectively). Foveal SCP and DCP vessel density in all studied eyes were positively correlated with the whole macular thickness, respectively (r = 0.556 and r = 0.627, respectively, both P < 0.001). Whole SCP and DCP vessel density in the amblyopic eyes were negatively correlated with choriocapillaris FV (r = -0.723, P < 0.001; r = -0.512, P = 0.001, respectively). Children with amblyopic eyes have attenuated macular and choriocapillaris perfusion. There is a need for future studies that will investigate the pathophysiology of amblyopia in children by OCTA.

Optical coherence tomography angiography for quantitative microvascular assessment in diabetic retinopathy: inter-device and intra-device agreement and correlation with clinical staging.

To compare acquisitions from single-volume Solix protocol (V1), multi-volume averaged Solix protocol (V4), and AngioVue in patients with diabetic retinopathy (DR) to assess differences in quantitative parameters introduced by high-speed scanning and averaging. Thirty-eight diabetic patients were divided into 4 groups showing either no sign, mild, moderate, or severe DR at fundus examination. For optical coherence tomography angiography (OCTA) acquisitions both AngioVue, Solix V1, and V4 were used on each patient. Outcome measures were macular perfusion density (PD), vessel length density (VLD), and vessel density index (VDI) for both superficial capillary plexus (SCP) and deep capillary plexus (DCP) and flow deficits (FD) in the choriocapillaris (CC). Our study revealed a good agreement in SCP parameters measured with all 3 devices. DCP measurements with Solix V1 showed moderate agreement with V4 and poor agreement with AngioVue measurements. Inter-device agreement in CC-FD assessment was relatively poor considering all 3 devices. The averaging process led to an underestimation of DCP and SCP parameters in all stages of DR (more evident in mild DR). AngioVue measurements compared to Solix V1 led to overestimation of SCP-PD (more pronounced in severe DR patients) and of DCP parameters (more evidently in moderate DR). The regression model derived from Solix V1 parameters was the best for categorization into the different stages. Averaging and high-speed scanning introduce changes in OCTA quantitative parameters in DR. Solix V1 is the most suitable for early diagnosis of DR, while averaged protocol could be the preferred choice in advanced stages of the disease.

Effect of Intravitreal Injection of Ranibizumab on Macular Perfusion by Optical Coherence Topography Angiography

Effect of Intravitreal Injection of Ranibizumab on Macular Perfusion by Optical Coherence Topography Angiography

Optical Coherence Tomography Angiography to Estimate Early Retinal Blood Flow Changes after Uncomplicated Cataract Surgery.

Background: To investigate macular microvascular changes after uncomplicated phacoemulsification surgery according to the cataract severity grade. Methods: Retrospective, cross-sectional study involving 23 eyes of 23 patients who underwent elective cataract extraction. All patients underwent routine ophthalmologic examination, including optical coherence tomography angiography (OCTA) at baseline (preoperative visit, T0) and seven days postoperatively (T7). OCTA scans were obtained with the spectral domain system Cirrus 5000 (Carl Zeiss Meditec, Inc., Dublin, CA, USA), and 3 mm × 3 mm raster fovea-centered scans were obtained to evaluate the superficial capillary plexus (SCP) vessel density, perfusion density, and foveal avascular zone (FAZ) parameters. Results: SCP perfusion density significantly increased from 28.3 ± 5.73% to 33.74 ± 4.13% after the surgery (p < 0.001). Similarly, SCP vessel density significantly increased from 15.14 ± 3.41 mm−1 to 18.14 ± 2.57 mm−1 after surgery (p < 0.001). The mean preoperative FAZ area significantly increased from 0.27 ± 0.12 mm to 0.24 ± 0.11 mm seven days postoperatively (p = 0.008). When comparing softer and harder cataracts, no significant variations in SCP vessel density, as well as SCP perfusion density parameters and the FAZ area, perimeter, and circularity index, were noted before and after surgery. Conclusions: Macular SPC vessel density and macular SCP perfusion density increase after uncomplicated cataract surgery regardless of the cataract severity.

Early Structural and Vascular Changes after Within-24 Hours Vitrectomy for Recent Onset Rhegmatogenous Retinal Detachment Treatment: A Pilot Study Comparing Bisected Macula and Not Bisected Macula.

Background: In this study we aimed at investigating macular perfusion/anatomical changes in eyes with early onset rhegmatogenous retinal detachment (RRD) after prompt surgery within 24 hours, comparing a bisected macula and not bisected macula RRD. Methods: In this prospective observational study, 14 eyes of 14 patients who underwent within-24 hours vitreoretinal surgery for early onset RRD were enrolled. Patients were further divided into two subgroups: the not bisected macula group (NBM group) and the bisected macula group (BM group). At baseline and 3-month follow up, macular architecture and vessel analysis were assessed using optical coherence tomography angiography (OCTA) imaging. In detail, quantitative and qualitative analyses of the macular area were performed to quantify topographical retinal perfusion changes after surgery, calculating the foveal avascular zone (FAZ), vessel density (VD) and vessel length density (VLD) at the superficial capillary plexus (SCP) and deep capillary plexus (DCP). Results: Most cases (43%) were superotemporal RRD. Primary retinal reattachment was obtained in all cases, without recurrences within 3-month follow up. After surgery, a significant FAZ enlargement was observed at both the SCP and DCP level (p < 0.001; p < 0.05), with a significant effect of time noted between the two time points in the NBM and BM subanalysis (F = 3.68; p < 0.017). An excellent functional outcome was maintained for the whole follow-up. On the other hand, after surgery, perfusion parameters did not change significantly apart from the vessel density of the inferior macular sector at the DCP level (p = 0.03). Conclusions: Our findings suggest that the macular perfusion of eyes with RRD is still preserved if the surgery is performed really promptly, thus highlighting the great importance of a correct timing for surgery. OCTA analysis allows for a better understanding of the pathophysiological mechanisms underneath early vascular microarchitecture modifications of the posterior pole in retinal detachment, differentiating the two types of RRD not completely involving the fovea (BM and NBM).