perfusion density
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2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Dulce Milagros Razo Blanco-Hernández ◽  
Selma Alin Somilleda-Ventura ◽  
Rebeca Chávez-Herrera ◽  
María Guadalupe Colas-Calvere ◽  
Virgilio Lima-Gómez

AbstractVessel and perfusion densities may decrease before diabetic retinopathy appears; it is unknown whether these changes affect the contribution of vessel density to perfusion density. This was a non-experimental, comparative, prospective, cross-sectional study in non-diabetic subjects (group 1) and diabetics without retinopathy (group 2). Vessel and perfusion densities in the superficial capillary plexus were compared between groups at the center, inner, and full regions and by field (superior, temporal, inferior, nasal) using optical coherence tomography angiography. Coefficients of determination (R2) between vessel and perfusion densities were calculated to find the contribution of larger retinal vessels to perfusion density. Percent differences were used to evaluate the contribution of these vessels to perfusion density in a regression model. There were 62 participants, 31 eyes by group; vessel and perfusion densities as well as the coefficients of determination between them were lower in group 2, especially in the nasal field (R2 0.85 vs. 0.71), which showed a higher contribution of larger retinal vessels to perfusion density. The regression model adjusted to a quadratic equation. In diabetics without retinopathy the contribution of vessel density to perfusion density may decrease; a low vessel density may increase the contribution of larger retinal vessels to perfusion density.


PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258479
Author(s):  
Kee Sup Park ◽  
Hyung Bin Lim ◽  
Yong Il Shin ◽  
Gi Seok Park ◽  
Woo Hyuk Lee ◽  
...  

Objective To investigate the effects of axial length (AL) on the peripapillary microvascular density acquired from optical coherence tomography angiography (OCTA). Methods Retrospective observational study. A total of 111 eyes from 111 normal healthy subjects were examined. The subjects were divided into three groups according to the AL: Group 1 (AL: < 24.0 mm; 35 eyes), Group 2 (AL: 24.0–25.99 mm; 37 eyes), and Group 3 (AL: ≥ 26 mm; 39 eyes). Peripapillary OCTA images were acquired using 6× 6 mm angiography scans, and vessel density (VD) and perfusion density (PD) of the superficial capillary plexus were calculated automatically. VD and PD were compared among the three groups according to the distance from the optic disc (inner and outer rings). Linear regression analyses were also performed to identify clinical factors associated with average VD. Results The average ALs of Groups 1–3 were 23.33± 0.57, 25.05± 0.60, and 27.42± 0.82, respectively. Average VD (P = 0.009) and PD (P = 0.029) in the inner ring increased with increasing AL. However, average VD (P < 0.001) and PD (P < 0.001) in the outer ring decreased with AL increased; the same trends were found for the full areas (VD, p<0.001; PD, p = 0.001). Average VDs in the inner and outer rings were not associated (P = 0.938). Conclusions Peripapillary VD and PD were significantly associated with AL. Depending on the distance from the disc, peripapillary VDs and PDs of the inner and outer rings were differentially affected by AL. Physicians should therefore consider the effects of AL in the analyses of peripapillary microvasculature.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Enrico Borrelli ◽  
Domenico Grosso ◽  
Mariacristina Parravano ◽  
Eliana Costanzo ◽  
Maria Brambati ◽  
...  

AbstractThe aim of this study was to measure macular perfusion in patients with type 1 diabetes and no signs of diabetic retinopathy (DR) using volume rendered three-dimensional (3D) optical coherence tomography angiography (OCTA). We collected data from 35 patients with diabetes and no DR who had OCTA obtained. An additional control group of 35 eyes from 35 healthy subjects was included for comparison. OCTA volume data were processed with a previously presented algorithm in order to obtain the 3D vascular volume and 3D perfusion density. In order to weigh the contribution of different plexuses’ impairment to volume rendered vascular perfusion, OCTA en face images were binarized in order to obtain two-dimensional (2D) perfusion density metrics. Mean ± SD age was 27.2 ± 10.2 years [range 19–64 years] in the diabetic group and 31.0 ± 11.4 years [range 19–61 years] in the control group (p = 0.145). The 3D vascular volume was 0.27 ± 0.05 mm3 in the diabetic group and 0.29 ± 0.04 mm3 in the control group (p = 0.020). The 3D perfusion density was 9.3 ± 1.6% and 10.3 ± 1.6% in diabetic patients and controls, respectively (p = 0.005). Using a 2D visualization, the perfusion density was lower in diabetic patients, but only at the deep vascular complex (DVC) level (38.9 ± 3.7% in diabetes and 41.0 ± 3.1% in controls, p = 0.001), while no differences were detected at the superficial capillary plexus (SCP) level (34.4 ± 3.1% and 34.3 ± 3.8% in the diabetic and healthy subjects, respectively, p = 0.899). In conclusion, eyes without signs of DR of patients with diabetes have a reduced volume rendered macular perfusion compared to control healthy eyes.


QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Karim Ahmed Hussein Ibrahim ◽  
Ahmed Abd Al Aleem Mohamed

Abstract Background Anterior ischemic optic neuropathy (AION) is divided into arteritic anterior ischemic optic neuropathy (AAION) which accounts for 15% and Nonarteritic anterior ischemic optic neuropathy (NAION) which accounts for 85% of cases. Non-arteritic anterior ischemic optic neuropathy (NAION) is an ischemic change involves the 1 mm thickness of the optic nerve head (optic disc). It affects around 10 cases per 100,000 per year in the age group over 50. Objective To assess the optical coherence tomography angiography peripapillary area pattern in diagnosed non-arteritic acute ischemic optic neuropathy patients within a period from one week to 3 weeks during (acute stage while the disc is still edematous) of acute painless diminution of vision. Patients and Methods We enrolled 20 patients in cases group and 10 patients in control group were enrolled to assess the OCTA peripapillary area pattern in diagnosed NAAION patients within a period from one week to 3 weeks during (acute stage while the disc is still edematous) of acute painless diminution of vision compared to the pattern seen in the normal control group OCTA, FFA and VF (centralized 30-2 SITA strategy) were done to the cases group. But FFA and VF were excluded in the control group. Results The results of our study show statistically significant difference found between the two studied groups regarding central circle perfusion density, middle circle perfusion density (superior, inferior and nasal) and outer circle perfusion density (superior and temporal) while no statistically significant difference found between them regarding middle circle (temporal) and outer circle (inferior and nasal). Conclusion So according to this study in cases of NAION (acute stage), we can depend on perfusion density within the middle and outer circle of Early Treatment Diabetic Retinopathy Study (ETDRS) grid put on the disc and peripapillary area. As, these are the areas affected by decreased perfusion density. While, there is increased perfusion density within the central and middle circles, which could be due to, diffuse disc edema.


2021 ◽  
Vol 4 (2) ◽  
pp. 119
Author(s):  
Sindi Dwijayanti ◽  
Irawati Irfani ◽  
Susanti Natalya Sirait ◽  
Elsa Gustianty ◽  
Erwin Iskandar ◽  
...  

Introduction: Impaired blood flow is an early sign of retinal dysfunction in diabetes. Impaired blood flow of the radial peripapillary capillaries can affect the Retinal Nerve Fiber Layer (RNFL) or ganglion cell function. Methods: This was an analytic cross-sectional study in February-April 2019 at Bandung. The subjects of this study were 41 people (79 eyes) divided into two groups, group A (healthy subjects) 19 people (37 eyes) and group B (DM type 2 without diabetic retinopathy) 22 people (42 eyes). Peripapillary retinal perfusion was assesed using OCT Angiography and RNFL thickness was assesed using OCT. Pearson or Spearman correlation statistics test was used to analyze the result. P value ≤0.05 was consiedered significant. Results: There was a decrease in peripapillary retinal perfusion density in the inferior quadrant (P = 0.003) and flux index throughout the peripapillary retinal quadrant (P = 0.0001) but an increase in RNFL thickness in the peripapillary temporal quadrant (P = 0.012) compared to control grup. Positive correlation was found between peripapillary retinal perfusion density and RNFL thickness globally (r = 0.480, P = 0.001), superior quadrant (r = 0.436, P = 0.004), and inferior quadrant (r = 0.608, P = 0.000). A positive correlation was also found between the peripapillary flux and RNFL thickness globally (r = 0.517, P = 0.000), superior quadrant (r = 0.630, P = 0.000), and inferior quadrant (r = 0.519, P = 0.000). Conclusions: There was a relationship between peripapillary retinal perfusion and RNFL thickness in DM patients without diabetic retinopathy. Keywords: Peripapillary perfusion, RNFL thickness, Diabetes.


Diagnostics ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1717
Author(s):  
Fiammetta Catania ◽  
Davide Allegrini ◽  
Alessandra Nembri ◽  
Filippo Confalonieri ◽  
Piero Zollet ◽  
...  

Lamellar macular holes (LMHs) may show morphological and functional deterioration over time, yet no definite prognostic factor for progression has been identified. Since neurovascular retinal unit impairment may take part in neurodegeneration, we compare progressive LMHs to stable ones in optical coherence tomography (OCT) angiography parameters. Methods: OCT B scans of eyes with LMH were analyzed to detect the presence of tissue loss (TL) over time, allowing us to identify a TL group and a stable (ST) group (14 patients each). The best corrected visual acuity (BCVA) at each considered imaging time point was collected. Lastly, patients underwent macular OCT angiography. Results: BCVA at last follow up was significantly reduced in the TL group compared to both the ST group and TL group baseline assessment. SCP foveal vessel density (VD), SCP and deep capillary plexus (DCP) perfusion density (PD) and parafoveal PD were lower in the TL group. Linear correlations between quantitative TL over time and parafoveal PD in SCP and between the speed of TL and BCVA variation during follow up were also detected. Conclusions: TL in LMHs is associated with both OCT angiography modifications and BCVA deterioration over time. We suggest these findings to be a manifestation of foveal Muller cell impairment in progressive LMHs.


2021 ◽  
pp. 112067212110437
Author(s):  
Carmen Plaitano ◽  
Francesca Periti ◽  
Rosanna Guagliano ◽  
Chiara Bertone ◽  
Donatella Barillà ◽  
...  

Purpose: The purpose of the present study was to investigate the perfusion density (PD) of macular superficial (SCP) and deep capillary plexus (DCP), the size of foveal avascular zone (FAZ) and central macular thickness (CMT) in healthy children using optical coherence tomography angiography (OCT-A). Patients and methods: About 206 eyes of 111 children were analyzed. The correlation of gestational age (GA), birth weight (BW), age, sex, refractive errors, and visual acuity (VA) with OCT-A parameters were investigated. Results: The mean PD of the fovea and the mean FAZ area of SCP were 17.1% (DS: 4.26) and 234.47 (DS: 106.39) µm2. The mean PD of the fovea and the mean FAZ area of DCP were 13.5% (DS: 5.23) and 298.32 (DS: 112.37) µm2. Superficial and deep FAZ areas were not correlated with sex, age, BW, refractive errors, or VA. FAZ area of SCP was correlated with foveal PD ( r = −0.76) and with CMT ( r = −0.68). FAZ area of DCP was correlated with foveal’s PD ( r = −0.61). There was no correlation between CMT and refractive errors. Conclusion: OCT-A may provide a non-invasive and reliable approach to evaluate macular perfusion in children. As the FAZ area, PD, and CMT change during the growth period, we performed established a reference range for different ages.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. Parravano ◽  
L. Ziccardi ◽  
E. Borrelli ◽  
E. Costanzo ◽  
S. Frontoni ◽  
...  

AbstractTo study the outer retina morpho-functional characteristics and the choriocapillaris (CC) features in type 1 diabetic (T1D) patients, with and without signs of diabetic retinopathy (NPDR and NoDR). Twenty-five NPDR and 18 NoDR eyes were imaged by Optical Coherence Tomography Angiography. Ellipsoid zone (EZ) “normalized” reflectivity and CC perfusion density parameters, as flow deficits number (FDn), flow deficit average area (FDa) and flow deficit percentage (FD%), were analysed. Multifocal electroretinogram (mfERG) response amplitude densities (RADs) were measured. Mean EZ “normalized” reflectivity, CC FDn and FD% values, were similar (p > 0.05) in both groups, FDa was significant greater (p > 0.05) in NPDR compared with NoDR eyes. MfERG-RADs were similar in both groups. NPDR eyes showed a significant (p < 0.05) linear correlation between RADs and both, CC FDa and FD%. The EZ “normalized” reflectivity was negatively correlated with CC FD% in NoDR eyes. In NPDR T1D eyes a significant relationship between abnormal outer retina functional responses and CC impairment was observed, while in NoDR eyes the photoreceptor reflectivity was correlated to CC abnormalities. The outer retina dysfunction in NPDR correlated to CC drop-out let hypothesize that the outer retinal elements are functionally impaired in proportion to the CC vascular supply deficit.


2021 ◽  
Vol 15 ◽  
Author(s):  
Ane Murueta-Goyena ◽  
Maitane Barrenechea ◽  
Asier Erramuzpe ◽  
Sara Teijeira-Portas ◽  
Marta Pengo ◽  
...  

BackgroundRetinal microvascular alterations have been previously described in Parkinson’s disease (PD) patients using optical coherence tomography angiography (OCT-A). However, an extensive description of retinal vascular morphological features, their association with PD-related clinical variables and their potential use as diagnostic biomarkers has not been explored.MethodsWe performed a cross-sectional study including 49 PD patients (87 eyes) and 40 controls (73 eyes). Retinal microvasculature was evaluated with Spectralis OCT-A and cognitive status with Montreal Cognitive Assessment. Unified PD Rating Scale and disease duration were recorded in patients. We extracted microvascular parameters from superficial and deep vascular plexuses of the macula, including the area and circularity of foveal avascular zone (FAZ), skeleton density, perfusion density, vessel perimeter index, vessel mean diameter, fractal dimension (FD) and lacunarity using Python and MATLAB. We compared the microvascular parameters between groups and explored their association with thickness of macular layers and clinical outcomes. Data were analyzed with General Estimating Equations (GEE) and adjusted for age, sex, and hypertension. Logistic regression GEE models were fitted to predict diagnosis of PD versus controls from microvascular, demographic, and clinical data. The discrimination ability of models was tested with receiver operating characteristic curves.ResultsFAZ area was significantly smaller in patients compared to controls in superficial and deep plexuses, whereas perfusion density, skeleton density, FD and lacunarity of capillaries were increased in the foveal zone of PD. In the parafovea, microvascular parameters of superficial plexus were associated with ganglion cell-inner plexiform layer thickness, but this was mainly driven by PD with mild cognitive impairment. No such associations were observed in controls. FAZ area was negatively associated with cognition in PD (non-adjusted models). Foveal lacunarity, combined with demographic and clinical confounding factors, yielded an outstanding diagnostic accuracy for discriminating PD patients from controls.ConclusionParkinson’s disease patients displayed foveal microvascular alterations causing an enlargement of the vascular bed surrounding FAZ. Parafoveal microvascular alterations were less pronounced but were related to inner retinal layer thinning. Retinal microvascular abnormalities helped discriminating PD from controls. All this supports OCT-A as a potential non-invasive biomarker to reveal vascular pathophysiology and improve diagnostic accuracy in PD.


2021 ◽  
Vol 14 (6) ◽  
pp. 860-868
Author(s):  
Ze-Bing Li ◽  
◽  
Na Li ◽  
Huan Yu ◽  
Yan-Lin Wu ◽  
...  

AIM: To evaluate the changes in fundus parameters in patients with Alzheimer’s type dementia (ATD) using optical coherence tomography angiography (OCTA), to record flash electroretinograms (ERG) using the RETeval system and to explore changes in retinal function. METHODS: Twenty-nine patients with ATD and 26 age-matched normal subjects were enrolled. All subjects underwent OCTA scans to analyse the superficial retinal vessel parameters in the macular area, including the vessel length density, the vessel perfusion density and the area of foveal avascular zone (FAZ), as well as the choroidal thickness. The differences between the patients with ATD and the normal control group were compared and explored the relevant factors affecting vessel parameters. We also recorded the flash ERGs using the RETeval system and intended to explore changes in retinal function by analysing the ERG image amplitude in patients with ATD. RESULTS: The vessel parameters [Pvessel length density=0.005 and Pvessel perfusion density=0.006) and average choroid thickness (P<0.001) in the macular area of the ATD group was less than the control group. The FAZ area was statistically significantly enlarged in the ATD group (P<0.001). These parameters were correlated with the Mini-Mental State Examination (MMSE) score and the Montreal Cognitive Assessment (MoCA). CONCLUSION: Patients with ATD exhibit decreases in the parameters associated with fundus. In addition, these indicators significantly correlate with the MMSE score and the MoCA score. OCTA may be an adjunct tool with strong potential to track changes in the diagnosis and monitoring the progression of the disease.


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