Quantitative evaluation of retinal microvasculature and retrobulbar vessels after intravenous chemotherapy for retinoblastoma

Backgroud To evaluate the changes in retinal microvasculature and retrobulbar blood flow, using optical coherence tomography angiography (OCTA) and Color Doppler imaging (CDI) after intravenous chemotherapy (IVC) in patients with retinoblastoma (RB). Methods This was a retrospective comparative case control series involving 30 patients. Ten bilateral RB patients that had a preserved eye with extramacular tumours (group I), 10 unilateral RB treated with IVC that had a normal fellow study eye (group II), and 10 age-matched healthy controls. The macular retinal thickness, foveal avascular zone (FAZ) area, and the macular and peripapillary retinal vessel densities (RVD) were measured. The peak systolic and end diastolic velocities of the ophthalmic, central retinal and posterior ciliary arteries were determined. A comparison among the three groups was conducted. Results Between the three cohorts, OCTA revealed no significant difference in FAZ area, superficial foveal and parafoveal RVD, deep parafoveal RVD and peripapillary RVD, (P > 0.05). By contrast, the mean deep foveal RVD, the full, inner and outer foveal and the parafoveal retinal thickness were significantly lower in group I compared with the controls, (P = 0.0329, 0.0153, 0.0311 0.0352, 0.0215). No significant difference in the blood flow velocities occurred in the retrobulbar circulation (P > 0.05). Conclusions In patients with retinoblastoma, OCTA did not detect significant changes of retinal thickness and vessel density in the eyes treated with IVC, but a slight reduction in retinal thickness and the deep foveal RVD seemed to occur in bilateral RB eyes. The retrobulbar blood flow parameters showed no measurable changes.

Quantitative Evaluation of Retinal Microvasculature and Retrobulbar Vessels After Intravenous Chemotherapy for Retinoblastoma

Backgroud : To evaluate the changes in retinal microvasculature and retrobulbar blood flow, using optical coherence tomography angiography (OCTA) and Color Doppler imaging (CDI) after intravenous chemotherapy (IVC) in patients with retinoblastoma (RB). Methods This was a retrospective comparative case control series involving 30 patients. Ten bilateral RB patients that had a preserved eye with extramacular tumours (group I), 10 unilateral RB treated with IVC that had a normal fellow study eye (group II), and 10 age-matched healthy controls. The macular retinal thickness, foveal avascular zone (FAZ) area, and the macular and peripapillary retinal vessel densities (RVD) were measured. The peak systolic and end diastolic velocities of the ophthalmic, central retinal and posterior ciliary arteries were determined. A comparison among the three groups was conducted. Results Between the three cohorts, OCTA revealed no significant difference in FAZ area, superficial foveal and parafoveal RVD, deep parafoveal RVD and peripapillary RVD, (P ༞ 0.05). By contrast, the mean deep foveal RVD, the full, inner and outer foveal and the parafoveal retinal thickness were significantly lower in group I compared with the controls, (P = 0.046, 0.020, 0.041, 0.044, 0.028). No significant difference in the blood flow velocities occurred in the retrobulbar circulation (P ༞ 0.05). Conclusions In patients with retinoblastoma, OCTA did not detect significant changes of retinal thickness and vessel density in the eyes treated with IVC, but a slight reduction in retinal thickness and the deep foveal RVD seemed to occur in bilateral RB eyes. The retrobulbar blood flow parameters showed no measurable changes.

Ocular Blood Flow Abnormalities and Their Correlation with Body Mass Index in Obese Patients

PurposeTo evaluate the effects of obesity on ocular blood flow including choroidal thickness and retrobulbar blood flow values in comparison with healthy subjectsMethodsThe 102 eyes of 102 female patients were included in this prospective study.Color Doppler ultrasonography (CDU) was used to evaluate the retrobulber vessels.Choroidal thickness was measured by using the optical coherence tomography (OCT). ResultsThere was a significant difference in IOP values within the groups with the highest values in group 3 and the lowest in group 1.There was also a positive correlation between BMI and IOP. The CT was found to be statistically significantly lower in group 2 and group 3 than in the control group at all measurement points. The choroidal thickness was also statistically significantly lower in group 3 than in group 2 at the subfoveal, nasal 500 µm, and the temporal 500 and 1000 µm measurement points.The mean CRA PSV and EDV values were lower in group 2 and group 3 than in group 1, while group 3 had the lowest mean CRA PSV value among the groups. When compared to group 1, the OA EDV value was lower only in group 3 while the OA PSV value was statistically significantly lower in group 3 than in both group 2 and group 1. There was no significant difference between the groups in terms of RI and PI.ConclusionsObesity can create a predisposition to ocular pathologies both by increasing the IOP and decreasing the retrobulbar and choroidal blood flow.

Correlation between retrobulbar blood flow parameters and retinal nerve fiber, ganglion cell and inner plexus layer thickness in myopia

Purpose: To assess the thickness of the retinal nerve fiber layer (RNFL), ganglion cell and inner plexus layer (GCIPL) and blood flow parameters in retrobulbar vessels, and to analyze correlations between these parameters in myopes. Methods: The study included forty myopic and 20 healthy eyes. Standard eye examination was supplemented with OCT of the optic nerve and macula (GCIPL, RNFL, RNFL in each quadrant and rim area of the optic nerve) and color Doppler imaging of retrobulbar arteries [peak systolic and end-diastolic velocities, pulsatile index and resistance index (RI) in the ophthalmic (OA), central retinal (CRA), nasal posterior ciliary and temporal posterior ciliary arteries]. Results: Significant correlations were found between blood flow parameters in the CRA, RNFL and GCIPL thickness, and axial length (AL) and spherical equivalent (SE). There were significant positive correlations between RNFL with PSV and EDV in the CRA and negative correlations between RNFL and RI in the CRA. GCIPL was positively correlated with PSV and EDV in the CRA. The decrease in RA was associated with reduced blood flow velocities in the CRA, TPCA and NPCA. Conclusion: The reduced retrobulbar blood flow in healthy young myopes is correlated with increasing AL and refractive value, and thinning of the RNFL and GCIPL. Reduction of the rim-area of the optic disc is associated with vascular and retinal circulatory disorders. These phenomena indicate the vascular basis of the described changes. To the best of our knowledge, this is the first study which correlates ocular circulation with retinal structure.

The Effect of Anthocyanins on Microcirculation and Retrobulbar Blood Flow in Ocular Pathology

The literature review presents information on positive effects of anthocyanins on functional indices of cardiovascular system, vascular reactivity of main arteries, microcirculation and retrobulbar blood flow. The positive effect of anthocyanins on the reactivity of main arteries was detected using non-invasive ultrasound method for assessment of flow-mediated dilation andendothelial function. Numerous randomised-controlled trials showed the effectiveness of the long-term supplementation with anthocyanins (during 6–24 months) in correction of microcirculation impairment and functional indices of visual system. The increase of plasma endothelin-1 (ET-1) level and the pathological vascular reactivity have been noted in ocular ischemic diseases such as diabetic retinopathy, occlusion of retinal veins and arteries. We registered the normalization of the plasma ET-1 level, significant improvement of blood flow in neuroretinal rim area and peripapillary area of retina without changes in mean indices of intraocular pressure and ocular perfusion pressure in patients with open-angle glaucoma after anthocyanins administration. There was no progression of visual fields defects. The resulting effect of anthocyanins supplementation consists of metabolic regulation of blood flow and flow-dependent vasodilatation due to the influence on vascular endothelium.Anthocyanins also increase the expression of endothelial nitric oxide (NO) synthase, an enzyme that generates powerful endogenous vasodilator NO. Anthocyanins regulate a number of complex immune and inflammatory signaling pathways involved in maintaining vascular functional activity. Positive dynamic of blood flow velocities and normalization of resistance indices in ocular vessels were detected in patients with dry age-related macular degeneration after 2 months anthocyanins supplementation. That indicates the improvement of ocular blood flow circulation and favorable prognosis for retinal dystrophies. The instrumental examination of blood flow in different vascular systems including microcirculation and main arteries are very useful for assessment of the effectiveness of anthocyanin supplementation.

Age-related changes in retrobulbar circulation: a literature review

Introduction The advances in research methods used in ophthalmology allow for an increasingly accurate examination of the eyes, as well as the morphology and function of the vessels. Colour Doppler imaging is still the first-line method for the analysis of parameters of retrobulbar circulation. Therefore, the aim of this work was to present the current state of knowledge about anatomical and functional age-related changes in retrobulbar arteries. Methods A literature search was performed mainly based on the PubMed database. Results The anatomy of retrobulbar arteries, histological background of age-related vascular changes, age-related changes in retrobulbar blood flow in the ophthalmic artery, central retinal artery, short posterior ciliary arteries, and the reference values for the age-dependent retrobulbar circulation parameters measured by colour Doppler imaging are discussed in this review. Conclusion The age of the subject should always be taken into account when interpreting the parameters of retrobulbar blood flow measured by colour Doppler imaging.