Reliability and validity of digital assessment of perifoveal capillary network measurement using high-resolution imaging

Faria, Jacqueline M. Lopes de; Duarte, Diego Andreazzi; Chavez, Roger Fredy Larico; Arthur, Angélica Moises; Arthur, Rangel; Iano, Yuzo

doi:10.1136/bjophthalmol-2013-304100

Cited by 15 publications

(8 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…18,28,30,31 The measurement procedure of retinal microcirculation using the RFI system has been described in detail previously. 18,31–33 RFI applies a stroboscopic light source and a high-resolution digital camera to rapidly take a series of retinal images.…”

Section: Methodsmentioning

confidence: 99%

Retinal Microvascular Network and Microcirculation Assessments in High Myopia

Jiang

et al. 2017

American Journal of Ophthalmology

190

162

View full text Add to dashboard Cite

Purpose To investigate the changes of the retinal microvascular network and microcirculation in high myopia. Design A cross-sectional, matched, comparative clinical study. Participants Twenty eyes of twenty subjects with non-pathological high myopia (28 ± 5 Years) with a refractive error of −6.31 ± 1.23 Diopters (mean ± standard deviation) and twenty eyes of twenty age- and gender-matched control subjects (30 ± 6 years) with a refractive error of −1.40 ± 1.00 Diopters were recruited. Methods Optical coherence tomography angiography (OCTA) was used to image the retinal microvascular network, which was later quantified by fractal analysis (box counting, Dbox, representing vessel density) in both superficial and deep vascular plexuses. The retinal function imager (RFI) was used to image the retinal microvessel blood flow velocity (BFV). The BFV and microvascular density in the myopia group were corrected for ocular magnification using Bennett’s formula. Results The density of both superficial and deep microvascular plexuses was significantly decreased in the myopia group in comparison to the controls (P < 0.05). The decrease of the microvessel density of the annular zone (0.6 – 2.5 mm), measured as Dbox, was 2.1% and 2.9% in superficial and deep vascular plexuses, respectively. The microvessel density reached a plateau from 0.5 mm to 1.25 mm from the fovea in both groups, but that in myopic group was about 3% lower than the control group. No significant differences were detected between the groups in retinal microvascular BFV in either arterioles or venules (P > 0.05). Microvascular densities in both superficial (r = −0.45, P = 0.047) and deep (r = −0.54, P = 0.01) vascular plexuses were negatively correlated with the axial lengths in the myopic eye. No correlations were observed between BFV and vessel density (P > 0.05). Conclusions Retinal microvascular decrease was observed in the high myopia subjects, whereas the retinal microvessel BFV remained unchanged. The retinal microvascular network alteration may be attributed to ocular elongation that occurs with the progression of myopia. The novel quantitative analyses of the retinal microvasculature may help to characterize the underlying pathophysiology of myopia and enable early detection and prevention of myopic retinopathy.

show abstract

Section: Methodsmentioning

confidence: 99%

Retinal Microvascular Network and Microcirculation Assessments in High Myopia

Jiang

et al. 2017

American Journal of Ophthalmology

190

162

View full text Add to dashboard Cite

show abstract

“…These new imaging modalities include optical coherence tomography angiography (OCT-A), ultrahigh-resolution optical coherence tomography with adaptive optics (UHR-AO-OCT), 1 dual-conjugate adaptive optics 11 and retinal function imager (RFI). 21 Among them, OCT-A has been introduced in daily clinical practice and has the potential to be an alternative to FA for several retinal vasculopathies. OCT-A is based on motion contrast instead of injecting an intravenous contrast dye to generate angiograms of the fundus comparable qualitatively and quantitatively to the FA, the current gold standard.…”

Section: Discussionmentioning

confidence: 99%

Assessment of a Novel Semi-Automated Algorithm for the Quantification of the Parafoveal Capillary Network

Kapsala¹,

Pallikaris²,

Tsilimbaris³

2023

OPTH

View full text Add to dashboard Cite

Introduction We present a novel semi-automated computerized method for the detection and quantification of parafoveal capillary network (PCN) in fluorescein angiography (FA) images. Material and Methods An algorithm detecting the superficial parafoveal capillary bed in high-resolution grayscale FA images and creating a one-pixel-wide PCN skeleton was developed using MatLab software. In addition to PCN detection, capillary density and branch point density in two circular areas centered on the center of the foveal avascular zone of 500μm and 750μm radius was calculated by the algorithm. Three consecutive FA images with distinguishable PCN from 56 eyes from 56 subjects were used for analysis. Both manual and semi-automated detection of the PCN and branch points was performed and compared. Three different intensity thresholds were used for the PCN detection to optimize the method defined as mean(I)+0.05*SD(I), mean(I) and mean(I)-0.05*SD(I), where I is the grayscale intensity of each image and SD the standard deviation. Limits of agreement (LoA), intraclass correlation coefficient (ICC) and Pearson’s correlation coefficient (r) were calculated. Results Using mean(I)-0.05*SD(I) as threshold the average difference in PCN density between semi-automated and manual method was 0.197 (0.316) deg −1 at 500μm radius and 0.409 (0.562) deg −1 at 750μm radius. The LoA were −0.421 to 0.817 and −0.693 to 1.510 deg −1 , respectively. The average difference of branch point density between semi-automated and manual method was zero for both areas; LoA were −0.001 to 0.002 and −0.001 to 0.001 branch points/degrees 2 , respectively. The other two intensity thresholds provided wider LoA for both metrics. The semi-automated algorithm showed great repeatability (ICC>0.91 in the 500μm radius and ICC>0.84 in the 750μm radius) for both metrics. Conclusion This semi-automated algorithm seems to provide readings in agreement with those of manual capillary tracing in FA. Larger prospective studies are needed to confirm the utility of the algorithm in clinical practice.

show abstract

“…This correlation might be partially due to the fact that a thicker retina has more metabolic needs and accordingly a smaller FAZ. 20 , 21 Unfortunately, we have not included thickness map in the current study.…”

Section: Discussionmentioning

confidence: 99%

Macular and Optic Nerve Microvascular Alteration in Relation to Axial Length, by Optical Coherence Tomography Angiography (OCTA)

Youssef¹,

Sadek²,

Hatata³

2022

OPTH

View full text Add to dashboard Cite

Reliability and validity of digital assessment of perifoveal capillary network measurement using high-resolution imaging

Abstract: The reliability of PCN measurement is reproducible and could be used as a new tool to quantify the capillary perfusion network of the macular area.

Cited by 15 publications

References 14 publications

Retinal Microvascular Network and Microcirculation Assessments in High Myopia

Retinal Microvascular Network and Microcirculation Assessments in High Myopia

Assessment of a Novel Semi-Automated Algorithm for the Quantification of the Parafoveal Capillary Network

Macular and Optic Nerve Microvascular Alteration in Relation to Axial Length, by Optical Coherence Tomography Angiography (OCTA)

Contact Info

Product

Resources

About