Color Doppler imaging of ocular hemodynamic changes in Behçet disease and uveitis patients with different etiologies

Assessment of Blood Flow Velocity in Retinal Vasculitis Using the Retinal Function Imager-A Pilot Study

Background: This pilot study aimed to evaluate the Retinal Function Imager (RFI) for visualizing retinal vasculature and assessment of blood flow characteristics in patients with retinal vasculitis. The RFI is a non-invasive imaging device measuring the blood flow velocity (BFV) in secondary and tertiary retinal vessels using hemoglobin as an intrinsic motion-contrast agent. Methods: To test the feasibility of the RFI for patients with retinal vasculitis, capillary perfusion maps (nCPMs) were generated from 15 eyes of eight patients (five females; mean age: 49 ± 12 years) with a mean uveitis duration of 74 ± 85 months. Five of these patients had birdshot chorioretinopathy, and three had primarily non-occlusive venous retinal vasculitis of unknown origin. To reflect that the BFV may be more reduced in patients with prolonged disease, patients were classified into a short-term (uveitis duration: 8-15 months) and a long-term uveitis group (uveitis duration: 60-264 months). Data were compared with healthy controls (16 eyes of 11 patients; mean age 45 ± 12 years; 8 females). Results: The mean BFV in the controls was 3.79 ± 0.50 mm/s in the retinal arteries and 2.35 ± 0.44 mm/s in the retinal veins, which was significantly higher compared to the retinal vasculitis group. Patients revealed an arterial BFV of 2.75 ± 0.74 mm/s (p < 0.001) and a venous BFV of 1.75 ± 0.51 mm/s (p = 0.016). In the short-term group, a trend towards a decreased venular and arteriolar BFV was seen, while a significant reduction was observed in the long-term group. The patients' microvasculature anatomy revealed by the nCPMs appeared unevenly distributed and a lower number of blood vessels were seen, along with a lower degree of complexity of their branching patterns, when compared with controls. Conclusions: This study demonstrated a reduction in venular and arteriolar BFVs in patients with retinal vasculitis. BFV alterations were already observed in early disease stages and became more pronounced in progressed disease. Additionally, we showed that retinal microvasculature changes may be observed by nCPMs. Retinal imaging with the RFI may serve as a diagnostic and quantifying tool in retinal vasculitis.

Retinal microvasculature features in patients with Behcet's disease: a systematic review and meta-analysis

This meta-analysis aimed to analyze retinal microvasculature features in eyes with Behçet's disease (BD) using optical coherence tomography angiography (OCTA). Electronic databases, including PubMed, Web of Science, Embase, and Cochrane Library, were comprehensively searched for published studies comparing retinal microvasculature characteristics between eyes with BD and controls. Continuous variables were calculated using the mean difference (MD) with 95% confidence interval (CI). Review Manager software (version 5.30) was used to conduct statistical analysis. A total of 13 eligible studies involving 599 eyes with BD and 622 control eyes were included in the meta-analysis. The pooled results showed that the macular whole enface superficial and deep vessel density (VD) values measured by OCTA were significantly lower in eyes with BD than in control eyes (superficial VD: MD = - 3.05, P < 0.00001; deep VD: MD = - 4.05, P = 0.0004). The foveal superficial and deep VD values were also significantly lower in the BD group than in the control group (superficial VD: MD = - 1.50, P = 0.009; deep VD: MD = - 4.25, -  = 0.03). Similarly, the analysis revealed a significant reduction in the parafoveal superficial and deep VD in eyes with BD than in control eyes (superficial VD: MD =  - 3.68, P < 0.00001; deep VD: MD = - 4.95, P = 0.0007). In addition, the superficial and deep foveal avascular zones (FAZs) were significantly larger in patients with BD than in controls (superficial FAZ: MD = 0.06, P = 0.02; deep FAZ: MD = 0.12, P = 0.03). The present meta-analysis found that macular whole enface VD, foveal VD, and parafoveal VD were lower in eyes with BD, and the FAZ was larger in patients with BD. The findings suggest that OCTA can assist clinicians in diagnosing and monitoring the status of patients with BD.

Quantitative Evaluation of the Retinal Vascular Parameters With OCTA in Patients With Behçet Disease Without Ocular Involvement

BACKGROUND AND OBJECTIVE

To evaluate the optical coherence tomography angiography (OCTA) features of patients with Behçet disease (BD) without ocular involvement.

PATIENTS AND METHODS

Twenty-three patients with BD without ocular involvement and 29 healthy age/sex-matched control subjects were involved. The authors measured foveal avascular zone (FAZ) area, vessel density in the parafoveal region, and flow area (fovea-centered 3-mm radius area) in the superficial and deep capillary plexuses evaluated by OCTA.

RESULTS

FAZ area was significantly larger in eyes with BD in both the superficial and deep capillary plexuses (0.331 vs. 0.240 mm² [P = .004] and 0.352 vs. 0.257 mm² [P = .003], respectively). Although mean capillary vessel density in parafoveal region and mean flow area were lower in eyes with BD for both superficial and deep capillary plexuses, these findings were not statistically significant.

CONCLUSION

Microvascular changes in macular region can be identified in patients with BD without ocular manifestation. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:31-34.].

Evaluation of retrobulbar blood flow and choroidal thickness in patients with rheumatoid arthritis

PURPOSE

To evaluate whether retrobulbar blood flow and choroidal thickness (CT) are affected in patients with rheumatoid arthritis (RA), and the relationship between these values.

METHODS

We evaluated 40 eyes of 20 RA patients and 40 eyes of 20 healthy controls. The enhanced depth imaging optical coherence tomography, color Doppler imaging, was held. Statistical analysis was performed.

RESULTS

Peak systolic velocity (PSV) of ophthalmic (OA) and central retinal artery (CRA) were significantly higher in RA. No significant difference was observed when end-diastolic velocity (EDV) of OA and CRA was compared between the groups. The resistivity index (RI) of OA and CRA was higher in RA. Perifoveal/subfoveal CT was lower in RA. Negative correlation was detected between the RI of OA and the perifoveal CT, and a positive correlation was detected between RI of CRA and CT.

CONCLUSIONS

Ocular hemodynamics is effected by RA and can exaggerate ocular complications of various vascular diseases such as diabetes mellitus, hypertension, retinal vascular occlusions.

Evaluation of resistive index using color Doppler imaging of orbital arteries in geriatric patients with hypertension

Background and Aim:

Resistive index (RI) is an indirect measurement of blood flow resistance that can be used to evaluate vascular damage in ophthalmologic disease. The purpose of this study was to evaluate the association between RI values of orbital arteries using the color Doppler imaging (CDI) in geriatric hypertensive patients with or without retinopathy.

Setting and Design:

Designed as a cross-sectional study.

Materials and Methods:

We evaluated 60 geriatric patients with hypertension (Group 1) and 30 healthy subjects (Group 2). Further, the patients with hypertension were grouped into two: Group 1a consisted of patients with retinopathy (n = 30), and group 1b consisted of patients without retinopathy (n = 30). The mean RI values of ophthalmic artery (OA), central retinal artery (CRA), and posterior ciliary artery (PCA) were measured using CDI.

Results:

Compared to group 2, group 1 had significantly higher mean resistive index of PCA levels (P = 0.017), whereas there were no statistical difference in mean resistive indexes of OA and CRA (both P > 0.05). Besides, there were no statistical difference in mean resistive indexes of OA, CRA, and PCA between the group 1a and group 1b (P > 0.05 for all). Mean resistive indexes of OA, CRA, and PCA were significantly correlated with the duration of hypertension (r = 0.268, P = 0.038; r = 0.315, P = 0.014; r = 0.324, P = 0.012, respectively).

Conclusions:

Our study indicates that RI might be a useful marker for the ocular hemodynamic of retinal vessels, provides morphologic and vascular information in hypertension and hypertensive retinopathy.

Short-term effects of intravitreal triamcinolone acetonide injection on ocular blood flow evaluated with color Doppler ultrasonography

AIM

To evaluate the changes in ocular blood flow with color Doppler ultrasonography (CDU) after intravitreal triamcinolone acetonide (IVTA) injection.

METHODS

A total of 46 patients who underwent IVTA (4 mg/0.1 mL) injection for diabetic macular edema (DME) (n=22), central retinal vein occlusion (CRVO) (n=12) and choroidal neovascular membrane (CNVM) (n=12) were included in the study. Peak systolic velocity (PSV), end diastolic velocity (EDV) and resistivity index (RI) were measured from the ophthalmic artery (OA), the central retinal artery (CRA) and the posterior ciliary artery (PCA) of each patient with CDU before, at the end of the first week and at the end of the first month following IVTA injection.

RESULTS

In the DME group, PSV of OA at the first of the first month (mean±SD) (37.48±10.87 cm/s) increased compared to pre-injection value (31.39±10.84 cm/s) (P=0.048). There was a statistically significant decrease (P=0.049) in PSV of CRA at the end of the first month (7.97±2.67 cm/s) compared to the pre-injection (9.47±3.37 cm/s). There was not any statistically significant difference on the other parameters in the DME group. Also, there was not any statistically significant difference on the ocular blood flow values in the CRVO and CNVM groups.

CONCLUSION

We observed that 4 mg/0.1 mL IVTA increased PSV of OA and decreased PSV of CRA in DME patients and did not have any effect on ocular blood flow values of CRVO and CNVM patients.

Gender differences in ocular blood flow

Gender medicine has been a major focus of research in recent years. The present review focuses on gender differences in the epidemiology of the most frequent ocular diseases that have been found to be associated with impaired ocular blood flow, such as age-related macular degeneration, glaucoma and diabetic retinopathy. Data have accumulated indicating that hormones have an important role in these diseases, since there are major differences in the prevalence and incidence between men and pre- and post-menopausal women. Whether this is related to vascular factors is, however, not entirely clear. Interestingly, the current knowledge about differences in ocular vascular parameters between men and women is sparse. Although little data is available, estrogen, progesterone and testosterone are most likely important regulators of blood flow in the retina and choroid, because they are key regulators of vascular tone in other organs. Estrogen seems to play a protective role since it decreases vascular resistance in large ocular vessels. Some studies indicate that hormone therapy is beneficial for ocular vascular disease in post-menopausal women. This evidence is, however, not sufficient to give any recommendation. Generally, remarkably few data are available on the role of sex hormones on ocular blood flow regulation, a topic that requires more attention in the future.

Color Doppler Imaging of the Orbital Vessels in Ankylosing Spondylitis

PURPOSE

To analyze the hemodynamic features of orbital blood flow velocities using Doppler ultrasonography in ankylosing spondiylitis (AS) patients, as well as to compare these results with those of healthy controls.

METHODS

33 AS patients and 32 healthy controls were consecutively included in the study groups. The same radiologist performed ocular blood flow measurements. Peak systolic velocity (PSV), end diastolic velocity (EDV), and resistive index (RI) were measured in the central retinal artery (CRA), posterior ciliary arteries (PCAs), and ophthalmic artery (OA). Resistive index was used to assess arterial resistance; it was automatically calculated as RI [(PSV-EDV)/PSV].

RESULTS

There were no significant differences in the PSV, EDV, and RI of the OA, CRA, and PCAs between AS patients and controls.

CONCLUSION

This result suggests no possible contributory role of vascular structures in formation of uveitis in AS. We believe that our preliminary results need to be complemented with further studies, particularly including AS patients with uveitis and rheumatic diseases with other ocular involvement.

Doppler sonography of ocular and carotid arteries in Behçet patients

PURPOSE

To evaluate by Doppler sonography carotid and ocular hemodynamics in Behçet disease with and without ocular involvement.

METHODS

Seventy-six patients with Behçet disease (BD) were separated into three groups: with active uveitis, with inactive uveitis, and without uveitis, and compared with 23 controls. We used duplex Doppler sonography to measure peak systolic (PSV), end-diastolic (EDV), and time-averaged mean (Vmean) blood flow velocity in the ophthalmic, central retinal (CRA), temporal posterior ciliary, nasal posterior ciliary (NPCA), common carotid (CCA), internal carotid (ICA) arteries, and maximum flow velocity (Vmax) in the central retinal veins. We then calculated resistance and pulsatility indexes of all arteries. Comparisons were carried out by two-way ANOVA and Holm-Sidak method.

RESULTS

Only two patients (2.6%) had atherosclerotic plaques, without significant hemodynamic consequence. Patients with uveitis had significantly lower ICA PSV and EDV (p < 0.05), and lower CRA PSV, EDV, and Vmean (p < 0.001) than controls. Patients with active uveitis had lower NPCA PSV and EDV than patients without uveitis or controls (p < 0.01). There were no differences in temporal posterior ciliary, ophthalmic, and CCA PSV, EDV, and in Vmean between groups (p > 0.05). Patients with uveitis had lower central retinal veins Vmax than patients without uveitis and than controls (p < 0.01). Resistance index, pulsatility index of retrobulbar arteries, CCA, and ICA were similar in the four groups (p > 0.05).

CONCLUSIONS

Patients with Behçet disease and ocular involvement have lower CRA, CRV, NPCA, and ICA blood flow velocities than healthy volunteers.

Changes of central retinal artery blood flow and endothelial function in patients with coronary artery disease

PURPOSE

In patients with coronary artery disease (CAD), endothelial function is usually impaired, but the parameters of central retinal artery (CRA) blood flow have not yet been investigated. We designed the study to test the parameters of CRA blood flow and brachial artery flow-mediated dilation (FMD), accompanied by an aim of establishing whether a link may exist between the parameters of CRA blood flow and endothelial function.

METHODS

Twenty-five subjects were diagnosed as CAD by coronary angiography, and 30 control subjects had normal coronary artery. CRA blood flow and brachial artery FMD were measured noninvasively using high-resolution ultrasound.

RESULTS

In patients with CAD, peak systolic velocity (PSV), end diastolic velocity (EDV), and time velocity integral (TVI) of CRA blood flow were significantly lower (8.75 +/- 2.09 vs. 10.15 +/- 2.16 cm/s, 2.55 +/- 0.73 vs. 3.81 +/- 0.90 cm/s, 5.01 +/- 1.32 vs. 6.27 +/- 1.28 cm/s, respectively, p = 0.019, p < 0.01, p < 0.01), conversely, pulsatility index (PI) and resistance index (RI) were significantly higher (1.28 +/- 0.22 vs. 1.01 +/- 0.20, 0.71 +/- 0.06 vs. 0.62 +/- 0.07, respectively, p < 0.01) when compared with those in normal controls. Meanwhile, brachial artery FMD was decreased in CAD patients (3.91 +/- 1.65 vs. 8.78 +/- 2.92, p < 0.01). After controlling for age, gender, heart rate, and blood pressure, the PSV, EDV, TVI, PI or RI in CRA blood flow were associated with the brachial artery FMD (r = 0.182, 0.372, 0.245, -0.320, or -0.367, respectively, p = 0.205, p = 0.008, p = 0.087, p = 0.023, or p = 0.009).

CONCLUSIONS

This study indicates that CRA blood flow is impaired in patients with CAD, and this may partly relate to endothelial dysfunction. Thus, endothelial function is likely to play an important role in the CRA microcirculation.