3D-FVS: construction and application of three-dimensional fundus vascular structure model based on single image features

BACKGROUND

Fundus microvasculature may be visually observed by ophthalmoscope and has been widely used in clinical practice. Due to the limitations of available equipment and technology, most studies only utilized the two-dimensional planar features of the fundus microvasculature.

METHODS

This study proposed a novel method for establishing the three-dimensional fundus vascular structure model and generating hemodynamic characteristics based on a single image. Firstly, the fundus vascular are segmented through our proposed network framework. Then, the length and width of vascular segments and the relationship among the adjacent segments are collected to construct the three-dimensional vascular structure model. Finally, the hemodynamic model is generated based on the vascular structure model, and highly correlated hemodynamic features are selected to diagnose the ophthalmic diseases.

RESULTS

In fundus vascular segmentation, the proposed network framework obtained 98.63% and 97.52% on Area Under Curve (AUC) and accuracy respectively. In diagnosis, the high correlation features extracted based on the proposed method achieved 95% on accuracy.

CONCLUSIONS

This study demonstrated that hemodynamic features filtered by relevance were essential for diagnosing retinal diseases. Additionally, the method proposed also outperformed the existing models on the levels of retina vessel segmentation. In conclusion, the proposed method may represent a novel way to diagnose retinal related diseases, which can analysis two-dimensional fundus pictures by extracting heterogeneous three-dimensional features.

Impact of cigarette smoking on fluorescence lifetime of ocular fundus

Cigarette smoking is known to adversely affect cellular metabolism and is a risk factor for various retinal diseases. Fluorescence lifetime imaging ophthalmoscopy (FLIO) has the potential to detect metabolic changes in the ocular fundus. Aim of this study was to analyze the influence of cigarette smoking on fluorescence lifetime (FLT) of healthy eyes using FLIO. Twenty-six non-smokers and 28 smokers aged between 20 and 37 years without systemic and ocular diseases were investigated by FLIO (excitation: 473 nm, emission: short spectral channel (SSC) 498-560 nm, long spectral channel (LSC) 560-720 nm). The FLT at the ETDRS grid regions were analyzed and compared. In SSC, the mean FLT (τ_m) of smokers was significantly longer in the ETDRS inner ring region, whereas the τ_m in LSC was significantly shorter in the outer ring. For the long component (τ₂), smokers with pack year < 7.11 showed significantly shorter τ₂ in SSC than non-smokers and the smokers with pack year ≥ 7.11. There were no significant differences in retinal thickness. The lack of obvious structural differences implies that the observed FLT changes are likely related to smoking-induced metabolic changes. These results suggest that FLIO may be useful in assessing retinal conditions related to lifestyle and systemic metabolic status.

IMI-The Dynamic Choroid: New Insights, Challenges, and Potential Significance for Human Myopia

The choroid is the richly vascular layer of the eye located between the sclera and Bruch's membrane. Early studies in animals, as well as more recent studies in humans, have demonstrated that the choroid is a dynamic, multifunctional structure, with its thickness directly and indirectly subject to modulation by a variety of physiologic and visual stimuli. In this review, the anatomy and function of the choroid are summarized and links between the choroid, eye growth regulation, and myopia, as demonstrated in animal models, discussed. Methods for quantifying choroidal thickness in the human eye and associated challenges are described, the literature examining choroidal changes in response to various visual stimuli and refractive error-related differences are summarized, and the potential implications of the latter for myopia are considered. This review also allowed for the reexamination of the hypothesis that short-term changes in choroidal thickness induced by pharmacologic, optical, or environmental stimuli are predictive of future long-term changes in axial elongation, and the speculation that short-term choroidal thickening can be used as a biomarker of treatment efficacy for myopia control therapies, with the general conclusion that current evidence is not sufficient.

Depression, anxiety and stress in Saudi migraine patients using DASS-21: local population-based cross-sectional survey

Background: Psychiatric comorbidity is common among migraineurs, such as anxiety and depression. This type of comorbidity contributed to migraine chronicity, management efficacy, and increasing the risk for other comorbidities. This study designed to estimate the prevalence of depression, anxiety, and stress (DAS) symptoms among Saudi migraine patients using the validated instrument (DASS-21) and considering socio-demographic factors and individual differences that affect migraine progression and prognosis.Design/methods: Cross-sectional, self-administered, web-based-questionnaire distributed among Saudi Arabia general population. Only migraine patients with clinical diagnosis allowed to complete the survey.Results: A total of 247 migraine patients participated and they are predominantly females, with ages between 16 and 45 years, Saudi nationals, married, non-smokers but do not exercise regularly. About 73.3% met the abnormal score in anxiety on DASS-21, as well as 70.9% in depression and 72.3% in stress. Four statistically significant correlations with DAS were identified. Migraine patients who are smoking have a higher prevalence of depression and stress (p < 0.05). Those who do not exercise regularly have a higher prevalence only for depression (p = 0.03). A higher prevalence of all emotional states was found in patients with more than one co-morbidity and patients with a clinical diagnosis of depression and anxiety disorders (p < 0.02). The sensitivity of DASS-21 for depression and anxiety are 96.9% and 93.3%, respectively.Conclusions: Both smoking cessation and exercise to prevent migraine attacks deserve a clinical trial. A holistic approach is needed to decrease psychiatry-related disability and promote management outcomes in migraineurs. Using DASS-21 for migraine patients as a routine screening instrument is valuable to prevent psychiatric comorbidity.

Acute effects of coffee consumption on the microcirculation of macula and optic nerve head

Purpose: This study aimed to evaluate the acute changes in retinal vasculature following coffee consumption. Methods: This is an interventional case series. The subjects were 22 healthy young adults. They were asked to rest in a silent room for 15 min; then, their heart rate, blood pressure, and arterial oxygen saturation pressure were measured with a single patient monitoring system. Optical coherence tomography (OCT) and OCT angiography (OCT-A) imaging of the disc and macula were performed for both eyes of the subjects. These measurements were repeated 45 min after drinking a cup of 450 ml of coffee containing a standard dose of 130 mg of caffeine. Macular and optic nerve head neurovasculature changes were assessed. Results: The results of our study did not show a significant change in peripapillary retinal nerve fiber layer thickness and neural structural and vascular parameters of the optic nerve head. Although assessments of macular vasculature showed a significant decrement in superficial (p = 0.01) and deep vessel density (p = 0.05) at parafovea, vessel densities (VDs) at the fovea, and deep capillary plexus at perifovea showed no significant change. Conclusion: Consuming one cup of coffee (150 mg caffeine) statistically changes central foveal thickness and parafoveal blood flow but likely does not have a clinical impact in healthy young adults.

Effects of Smoking on Optic Nerve Head Microvasculature Density in Glaucoma

PRCIS

Decreased superficial whole image capillary density was observed in open angle glaucoma (OAG) patients with high smoking intensity.

PURPOSE

To investigate the effects of smoking on optic nerve head capillary density measured by optical coherence tomography angiography in patients with OAG.

METHODS

In this retrospective cross-sectional study, perimetric and preperimetric glaucoma patients enrolled in the Diagnostic Innovations in Glaucoma Study (DIGS) with optical coherence tomography angiography follow-up were included. Univariable and multivariable linear mixed analysis were performed to determine the effects of different variables on the superficial whole image capillary density.

RESULTS

A total of 432 eyes of 271 glaucoma patients comprising 63 preperimetric (106 eyes) and 208 perimetric OAG (326 eyes) were included. A history of tobacco consumption was reported in 105 (38.8%). Among smokers, mean (95% confidence interval) smoking intensity was 12.8 (10.2, 15.5) pack-years. After adjusting for age, glaucoma severity and other confounders, each 10 pack-year increase in smoking intensity (95% confidence interval) was associated with -0.54 (-1.06, -0.02) % lower whole image capillary density ( P =0.041).

CONCLUSIONS

Smoking intensity is associated with reduced optic nerve vessel density in glaucoma.

Repeatability and Reproducibility of 4.5 by 4.5 mm Peripapillary Optical Coherence Tomography Angiography Scans in Glaucoma and Nonglaucoma Eyes

PRCIS

Peripapillary vessel parameters from optical coherence tomography angiography (OCTA) 4.5×4.5 mm scans in nonglaucomatous and glaucomatous eyes showed high repeatability and reproducibility, with higher reliability for commercially developed OCTA parameters compared with custom OCTA parameters.

PURPOSE

The purpose of this study was to assess intrasession repeatability versus intersession reproducibility of peripapillary vessel parameters from 4.5×4.5 mm OCTA scans in nonglaucomatous eyes and glaucomatous eyes.

MATERIALS AND METHODS

In a longitudinal study, peripapillary OCTA scans were quantified using research-oriented custom quantification software that calculated vessel area density (VAD) and flux and clinic-oriented commercially developed software (Cirrus 11.0) that calculated perfusion density (PD) and flux index (FI). Intrasession repeatability and intersession reproducibility were evaluated using within-eye coefficient of variation (CVW) and intraclass correlation coefficient (ICC).

RESULTS

With 127 nonglaucomatous eyes, intrasession CVW for VAD, PD, flux, and FI were 1.900%, 1.174%, 2.787%, and 1.425%, respectively. The intersession CVW were 2.039%, 1.606%, 4.053%, and 2.798%, respectively. Intrasession ICC ranged from 0.903 to 0.956, and intersession ICC ranged from 0.850 to 0.896. Among 144 glaucomatous eyes, intrasession CVW for VAD, PD, flux, and FI were: 3.841%, 1.493%, 5.009%, and 2.432%, respectively. The intersession CVW were 4.991%, 2.155%, 6.360%, and 3.458%, respectively. Intrasession ICC ranged from 0.956 to 0.969, and intersession ICC ranged from 0.918 to 0.964.

CONCLUSIONS

Among nonglaucomatous and glaucomatous eyes, the majority of peripapillary OCTA vessel parameters from 4.5×4.5 mm scans had greater intrasession repeatability than intersession reproducibility. There was a greater agreement for the commercially developed quantification parameters than for their custom quantification counterparts.

Intrasession Repeatability and Intersession Reproducibility of Macular Vessel Parameters on Optical Coherence Tomography Angiography in Glaucomatous and Non-Glaucomatous Eyes

PURPOSE

Using optical coherence tomography angiography (OCTA), this study compared intrasession repeatability versus intersession reproducibility of macular vessel parameters in glaucoma and non-glaucoma subjects.

METHODS

6x6 mm² macular OCTA scans (Cirrus HD-OCT 5000) were acquired from glaucomatous and non-glaucomatous subjects as part of an observational, longitudinal study. Vessel area density (VAD) and vessel skeleton density (VSD) were calculated using research-based quantification software while perfusion density (PD_Z) and vessel density (VD_Z) were calculated using commercially developed software (Cirrus 11.0, Carl Zeiss Meditec). Intrasession repeatability and intersession reproducibility were determined using within-eye standard deviation (S_W), within-eye coefficient of repeatability (CR_W), within-eye coefficient of variation (CV_W), and intraclass correlation coefficients (ICC).

RESULTS

The intrasession repeatability and intersession reproducibility for macular OCTA parameters were similar to one another for both non-glaucomatous and glaucomatous eyes. Intrasession CV_W from the non-glaucoma group (n = 73) was 1.097% for VAD, 1.007% for VSD, 2.980% for PD_Z, and 2.714% for VDZ. Intersession CV_W from the non-glaucoma group (n = 55) was 1.389% for VAD, 1.279% for VSD, 2.935% for PD_Z, and 2.695% for VD_Z. Intrasession CV_W from the glaucoma group (n = 59) was 1.189% for VAD, 0.970% for VSD, 3.827% for PD_Z, and 3.542% for VD_Z. Intersession CV_W from the glaucoma group (n = 45) was 1.412% for VAD, 1.132% for VSD, 3.915% for PD_Z, and 3.654% for VD_Z. Non-glaucomatous intrasession ICC ranged from 0.711 to 0.824, non-glaucomatous intersession ICC ranged from 0.649 to 0.762, glaucomatous intrasession ICC ranged from 0.710 to 0.853, and glaucomatous intersession ICC ranged from 0.661 to 0.827.

CONCLUSIONS

Macular OCTA scans can be a useful tool in monitoring the longitudinal progression of glaucoma due to its high repeatability and reproducibility.

Acute effect of pseudoephedrine on macular microcirculation in healthy subjects: an optical coherence tomography angiography study

PURPOSE

To quantitatively evaluate the acute effects of pseudoephedrine on the macular microvasculature using optical coherence tomography angiography (OCTA).

STUDY DESIGN

Randomized placebo-controlled clinical study.

METHODS

In this study, 60 right eyes of 60 healthy subjects were divided into 2 groups. The study group received 60 mg of pseudoephedrine and the control group received a placebo. All participants underwent OCTA at baseline and 1 h after oral intake. Superficial macular flow area, foveal avascular zone (FAZ), superficial macular vessel density, central foveal thickness (CFT) and subfoveal choroidal thickness (SFCT) were analyzed.

RESULTS

Baseline superficial macular flow area, FAZ area, superficial macular vessel density, CFT and SFCT measurements in the study and control groups showed no significant difference (p > 0.05 for all). Oral pseudoephedrine intake caused a significant reduction in superficial macular flow area, FAZ area, superficial macular vessel density and SFCT measurements when compared with baseline (p < 0.05 for all). However, there was no significant difference in CFT after oral pseudoephedrine intake (p > 0.05).

CONCLUSION

Oral pseudoephedrine intake causes a significant decrease in superficial macular blood flow and SFCT. Impairmant of macular microcirculation can be detected noninvasively and quantitavitely by OCTA.

[Optical coherence tomography angiography and cardiovascular diseases. An overview of the current knowledge]

Hintergrund

Kardiovaskuläre Erkrankungen (KVE) sind die Haupttodesursache weltweit. Die Beobachtbarkeit von Veränderungen der retinalen Gefäße im Zusammenhang mit KVE mittels Fundoskopie ist schon seit Langem bekannt. Ein neuartiges Verfahren zur nichtinvasiven und detaillierten Darstellung und Quantifizierung der retinalen und papillären Gefäße stellt die optische Kohärenztomographie-Angiographie (OCT-A) dar. Durch die OCT‑A ist es möglich, Gefäßveränderungen einfach und gut reproduzierbar zu visualisieren, weswegen ihr Einsatz nicht nur auf augenärztliche Fragestellungen beschränkt ist. In den vergangenen Jahren sind einige experimentelle und klinische Studien zur Darstellbarkeit und Quantifizierung von Gefäßveränderungen durch die OCT‑A bei Erkrankungen des kardiovaskulären Spektrums publiziert worden. In der vorliegenden Übersicht werden die wichtigsten Erkenntnisse aus diesen Studien zusammengefasst.

Methoden

Grundlage dieser Arbeit bilden eine umfassende selektive Literaturrecherche und die Darstellung eigener Daten.

Ergebnisse

Mittlerweile liegen zu vielen Erkrankungen des kardiovaskulären Spektrums OCT-A-Studien vor, die verdeutlichen, dass systemische Gefäßerkrankungen mit Veränderungen der retinalen Mikrozirkulation verbunden sind. Mit der OCT‑A können diese Veränderungen visualisiert und reproduzierbar quantifiziert werden. Oftmals ist es möglich, subklinische Veränderungen aufzuzeigen, bevor die zugrunde liegende Erkrankung anderweitig messbare Veränderungen oder für den Patienten merkbare Symptome verursacht.

Schlussfolgerung

Die OCT‑A ist eine vielversprechende Bildgebungsmethode auf dem Gebiet der KVE in Wissenschaft und klinischer Anwendung. Sie kann zur Diagnostik und Quantifizierung retinaler Gefäßveränderungen eingesetzt werden. Weitere Studien werden zeigen, ob die OCT‑A bei der Einschätzung des individuellen kardiovaskulären Risikoprofils helfen kann.

Migraine-Related Disabilities Among Saudi Migraine Patients and Its Association with Social Factors

Background: Migraine is a complex disorder triggered by an interaction of multiple abnormalities involving genes, blood vessels, and brain structures. It is characterized by throbbing headaches, mostly on one side of the head. It is one of the most common causes of disability, as announced by the Global Burden of the Diseases (GBD). Objectives: We aimed at assessing disabilities in Saudi migraine patients and addressing the relation between migraine-associated disabilities and social factors in Saudi Arabia. Methods: We conducted a web-based survey randomly through social media channels to the general population around Saudi Arabia. Basic personal information, along with a confirmation of the migraine diagnosis, were included in the first part of the questionnaire, and the respondent’s eligibility was determined to complete the survey. Specified questions about the sociodemographic characteristics, migraine attacks and medications, and the items of Migraine Disability Assessment score (MIDAS), were included in the next parts of the survey. Results: Of the 480 total responses, 250 (52.1%) eligible participants were included (mean age of 34.84 ± 10.14 years; 83.2% females). Most of the participants were married (59.6%), had three or more kids (50.7%), had a bachelor’s degree (60.8%), and 52.8% were employed. Only 16.4% of the subjects did regular exercise, and 16.8% were current smokers. No significant association was detected between the MIDAS score and most of the social characteristics, including marital status, number of kids, education level, occupation, and smocking. Conclusions: Most of the migraineurs in Saudi Arabia had a severe disability according to the MIDAS score. Gender, regular exercise, the severity of the disease, and frequency of attack had a statistically significant relationship with migraine-related disabilities. Migraine treatment and prophylaxis were incompetent in decreasing migraine severity and related disabilities in our selected participants.

Intrasession repeatability and intersession reproducibility of peripapillary OCTA vessel parameters in non-glaucomatous and glaucomatous eyes

OBJECTIVE

To compare intrasession repeatability versus intersession reproducibility of the peripapillary vessel parameters using optical microangiography-based optical coherence tomography angiography (OCTA) in non-glaucomatous and glaucomatous eyes.

METHODS

In an observational, longitudinal study, peripapillary OCTA scans were collected to evaluate intrasession repeatability and intersession reproducibility using within-eye coefficient of variation (CV_W) and intraclass correlation coefficient (ICC). Images were quantified using a custom research-oriented quantification software calculating vessel area density (VAD) and flux and a commercially developed, clinic-oriented quantification software (Cirrus 11.0, Carl Zeiss Meditec) calculating perfusion density (PD) and flux index (FI). Effect of signal strength on the reliability of OCTA parameters was also evaluated.

RESULTS

Among 120 non-glaucomatous eyes, intrasession CV_W were 4.2% for VAD, 5.3% for flux, 1.5% for PD and 2.0% for FI. The intersession CV_W were 6.5% for VAD, 8.0% for flux, 2.0% for PD and 3.2% for FI. The intrasession ICC ranged from 0.928 to 0.945, and intersession ICC ranged from 0.811 to 0.866. From 118 glaucomatous eyes, intrasession CV_W was 9.0% for VAD, 10.3% for flux, 1.7% for PD and 2.3% for FI. The intersession CV_W was 12.1% for VAD, 14.2% for flux, 2.3% for PD and 3.5% for FI. The intrasession ICC ranged from 0.904 to 0.972, and intersession ICC ranged from 0.855 to 0.955. Signal strength was significantly positively associated with OCTA vessel parameters (p<0.0001) for both groups.

CONCLUSION

Peripapillary OCTA vessel parameters had greater intrasession repeatability compared to intersession reproducibility in both non-glaucomatous and glaucomatous eyes. The built-in commercially developed quantification software demonstrated greater agreement than the custom research-oriented quantification software.