Choroidal Blood Flow In Patients Research Articles

Choroidal Changes in Blood Flow in Patients with Intermediate AMD after Oral Dietary Supplement Based on Astaxanthin, Bromelain, Vitamin D3, Folic Acid, Lutein, and Antioxidants.

Background and Objectives: The aim of this study was to investigate the impact of oral administration of the combination of astaxanthin (AXT), lutein, folic acid, vitamin D3, and bromelain with antioxidants on choroidal blood flow in patients with age-related intermediate macular degeneration (AMD). Materials and Methods: Patients affected by intermediate AMD and treated with daily oral nutritional supplement with AXT, bromelain, vitamin D3, folic acid, lutein, and antioxidants for a period of at least 6 months were included in this retrospective study. A control group homogenous for age and sex was also included in the analysis. All participants underwent a complete ophthalmologic examination, spectral domain optical coherence tomography (SD-OCT), and optical coherence tomography angiography (OCTA) evaluation. Outcome measures were choroidal thickness (CHT) and choriocapillary vessel density (CCVD) after six months of AXT assumption. Results: CCVD values showed statistically significant difference between cases and controls at baseline (p < 0.001) and in the cases during follow-up (p < 0.001). The CHT measurements showed statistically significant difference between cases and controls (p = 0.002) and in the cases during follow-up (p < 0.001). Conclusions: The combined use of structural OCT and OCTA allows for a detailed analysis in vivo of perfusion parameters of the choriocapillaris and choroid and evaluation of changes of choroidal blood flow after oral nutritional supplements that affect blood flow velocity.

Long-term changes of choroidal blood flow velocity in Vogt-Koyanagi-Harada disease.

To evaluate changes in choroidal blood flow in patients with Vogt-Koyanagi-Harada (VKH) disease after initiation of corticosteroid treatment. Fourteen patients (10 men and 4 women) with acute VKH disease followed for 2years were retrospectively reviewed; only right eyes were included in the analysis. Mean blur rate (MBR) in the macula was measured by laser speckle flowgraphy (LSFG) and central choroidal thickness (CCT) was measured by optical coherence tomography (OCT), both prior to treatment and over 2years after initiation of corticosteroid treatment. Of 14 patients included in this study, 13 received initial treatment consisting of intravenous corticosteroid pulse therapy and one patient was treated using bilateral sub-Tenon injections of triamcinolone acetonide. Mean percentage change in MBR was significantly increased after initiation of treatment compared to pretreatment values (P < 0.001). Mean CCTs were significantly decreased after initiation of treatment, compared to pretreatment thicknesses (P < 0.001). There was no significant change in either MBR change or CCT at 1month after initiation of treatment through 2years of follow-up. The mean MBR percentage change was significantly higher in eyes with sunset glow fundus (SGF) compared to eyes without SGF at 1year. With initiation of corticosteroid treatment in VKH disease patients, choroidal blood flow improved and was maintained for 2years. However, the presence of SGF should be taken into consideration when interpreting MBR results in VKH disease patients.

Changes in choroidal blood flow in patients with macular hole after surgery

IntroductionA macular hole (MH) is a defect that occurs in the retina and involves all layers. In this study, we aimed to investigate the preoperative and postoperative choriocapillaris blood flow (CBF) changes in patients with MH and the role of CBF in the pathogenesis of the disease using optical coherence tomography angiography (OCTA). Material methodThis is a retrospective study examining eyes with MH. The study included 25 operated eyes of 25 patients and contralateral eyes of 18 patients. CBF and subfoveal choroidal thickness were examined using the OCTA images of the patients before surgery and at the first, third and sixth months after surgery. ResultsThe mean CBF value of the patients was 1.57±0.20 mm² preoperatively, 1.94±0.13 mm² at the postoperative first month, 1.98±0.12 mm² at the third month, and 2.00±0.10 mm² at the sixth month. The increases in the CBF values between the preoperative period and the postoperative measurements were statistically significant (p<0.0001 for all). In the preoperative period, the CBF value of the contralateral eyes was 2.07±0.10 mm². The preoperative CBF value of the contralateral eyes was higher compared to that of the eyes with MH (p<0.0001). There was no significant difference between the preoperative CBF value of the contralateral eyes and the postoperative sixth-month value of the eyes with MH (p = 0.065). ConclusionThe preoperative and postoperative third-month CBF values of the eyes with MH were found to be lower than those of the contralateral eyes, but there was no difference between the postoperative sixth-month CBF value of the eyes with MH and the preoperative CBF value of the contralateral eyes. We consider that the eyes with MH achieve similar CBF values to the contralateral eyes in an average of six months after successful surgery.

Increased choroidal blood flow and choroidal thickness in patients with hypertensive chorioretinopathy.

To investigate the alterations of central choroidal thickness (CCT) and macular choroidal blood flow in patients with hypertensive chorioretinopathy treated with antihypertensive agents. In retrospective observational case series, ten eyes of 9 patients with hypertensive chorioretinopathy were enrolled (5 men and 4 women; 43.1 ± 19.6years of age). CCT and mean blur rate (MBR) had been observed during follow-up using enhanced depth imaging optical coherence tomography and laser speckle flowgraphy, respectively. With the medication for hypertension, serous retinal detachment (SRD) disappeared in all the eyes (mean period, 57.8 ± 50.4days), and the mean blood pressure decreased (122.7 ± 13.0mmHg and 93.4 ± 13.2mmHg at the initial visit and at the day of subretinal fluid absorption, respectively; P < 0.01). The mean logMAR value of best corrected visual acuity showed a tendency toward improvement with the resolution of SRD (0.15 ± 0.30 and 0.08 ± 0.28, P = 0.15). The average MBR significantly decreased when SRD was absorbed (11.4 ± 4.5 and 7.7 ± 2.2, P < 0.01). Similarly, the mean values of CCT decreased (473.2 ± 218.0μm and 325.7 ± 112.0μm, P < 0.01). The changing rates of CCT and MBR showed a significant positive correlation (P < 0.01, R = 0.88). The current study demonstrated a novel finding that choroidal blood flow velocity and thickness concurrently increased in the acute phase of hypertensive chorioretinopathy, suggesting the role of choroidal hyperperfusion in the pathogenesis of hypertensive chorioretinopathy.

Central Serous Chorioretinopathy from the Point of View of OCT-Angiography. Part 1. Chorioretinal Blood Flow Changes

Numerous recent studies indicate that the key mechanism for the development of central serous chorioretinopathy (CSR) is damage to retinal pigment epithelium (RPE). At the same time, the reports appeared in recent years indicate that an equally important link in pathogenesis is the disturbances of the choroidal blood flow. Thus, the introduction into clinical practice of optical coherence tomography in the angiography (OCTA) mode made it possible to visualize the retinal and choroidal vessels taking into account their segmentation, which opens up prospects for studying chorioretinal blood flow in the CSR.Purpose:to reveal the regularities of the change in the choroidal blood flow in patients with SCR according to the OCTA data, to assess their informativeness and role in the pathogenesis of the disease.Patients and methods:26 patients with SCR aged 35–54 years were examined. To assess the chorioretinal blood flow, optical coherence tomography of the retina is included in the angiography mode in the scope of the diagnostic examination.Results and discussion:It has been revealed that the number of large vessels in the immediate vicinity of the RPE is increasing in SCR, i.e. the vessels move towards the retina in the direction of the least resistance. Disturbance of the hierarchy of the vasculature is an important fact, allowing to speak about pronounced hemodynamic disorders. Disturbance of the topography of large-caliber vessels is accompanied by the formation of a characteristic vascular pattern. The revealed predominance of the reticular pattern of large vessels in patients with CSR is more likely due to the presence of a significant number of bifurcations and anastomoses, as well as an increase in the proportion of crossed vessels. This may be accompanied by an increase in total vascular resistance. Consequently, the hydraulic resistance can increase at these sites, a turbulent blood flow occurs and the permeability of the vascular wall increases. Correspondence between changes in RPE and choriocapillaries was established. Taking into account that the RPE detachments from 450 to 780 (on average 515 ± 72.3) μm, revealed in the projection of the altered choriocapillaries, have comparable sizes with the value of one vascular lobe (515 × 450) μm, one can speak of a local lesion of choriocapillaries and RPE within one arteriocentric lobules.Conclusions:The revealed changes in regional blood flow are progressive and can be used as classification and prognostic criteria for choroidal dysfunction.

DYSFUNCTIONAL AUTONOMIC REGULATION OF THE CHOROID IN CENTRAL SEROUS CHORIORETINOPATHY.

To study the effect of changing perfusion pressures on retinal and choroidal structure in central serous chorioretinopathy (CSC). This prospective observational case series included seven healthy volunteers (14 eyes) and seven patients (14 eyes) with CSC. Each patient underwent spectral domain optical coherence tomography with enhanced depth imaging in the upright (sitting) and supine positions. Image segmentation focused on central macular thickness, subretinal fluid, total macular volume, choroidal thickness, and choriocapillaris thickness. Blood pressure and heart rate were measured in the upright and supine positions. Choriocapillaris thickness was thicker in CSC participants (34.23 μm; range, 30.9-36.5 μm) compared with healthy controls (13.96 μm; range, 7.15-23.87 μm) (P ≤ 0.001). The choroid was similarly thicker in CSC participants (371.4 μm; range, 200.2-459.4 μm) compared with healthy controls (231.4 μm; range 161.8-287.5 μm) (P ≤ 0.001). Choroidal thickness increased in patients with CSC when transitioning from upright (371.4 μm) to supine (377.8 μm) (P ≤ 0.01). By contrast, there was an 11.97% decrease in choroid thickness in normal controls when transitioning from upright (231.4 μm) to supine (203.9 μm). There were no significant hemodynamic changes. We demonstrated that choroidal thickness increased in response to increased perfusion pressures in patients with CSC and not in normal controls. These findings likely represent an autonomic dysregulation of choroidal blood flow in patients with CSC.

Morphometric and hemodynamic features of the age-related macular degeneration course in combined pathology: age-related macular degeneration in association with glaucoma

Purpose. To determine the characteristics of anatomical retinal changes and of the choroidal blood flow in patients with combined pathology: age-related macular degeneration (AMD) and primary open-angle glaucoma (POAG). Materials and methods. We investigated two study groups (SG): SG1 - AMD in association with POAG, 113 patients; SG2 - AMD without glaucomatous nerve damage , 92 patients; mean age - 71.9 ± 9.3 years. Measurements of the neuro-sensory retina (NSR) thickness and of the ganglion cells complex (GCC) thickness by optical coherence tomography (OCT) in manual regimen (42 eyes in SG1, 38 eyes in SG2) and the estimation of choroidal blood flow (HBF) by ultrasonography (18 eyes in SG1, 38 eyes in SG2) were performed in two areas: area I - 4 mm laterally to the optic nerve head; area II - 4 mm medially to the optic nerve head. Results. The GCC thickness in patients with combined pathology (SG1) was significantly lower than in patients with AMD (IG2) in the areas I and II; the thickness index of the GCC was significantly reduced in SG1 in areas I and II, whereas in SG2 this index was increased. Significant differences of HBF in areas I and II in SG1 were found, as well as reduced peak systolic flow velocity, the time-averaged maximum velocity of blood flow, maximum end-diastolic flow velocity, as compared with SG2. The index of peripheral resistance was reduced in SG1 in area I and increased in area II, whereas in SG2 it was increased in area I and reduced in area II. Conclusion. In patients with combined pathology - AMD and POAG - NSR thickness was reduced due to the thinning of the ganglion cell layer and the formation of an ischemic pattern of choroidal blood flow in the macula and medially to the optic nerve head.

Choroidal blood flow and choroidal thickness

AbstractA progressive decrease of the choroidal blood flow related to macular degeneration was observed with glaucoma and aging. Abnormal regulation of the choroidal blood flow in patients suffering from neovascular AMD or Diabétic microangiopathy was also reported. Recent clinical studies have shown a decrease of the choroidal thicknessof in high myopia, AMD or in retinal dystrophies and increased choroidal thickness in central serous chorioretinopathy. Continuous real time Laser Doppler Flowmetry (LDF) has been used in humans for the evaluation of the subfoveal choroidal circulation and the investigation of the regulatory processes of the choroidal blood flow in response to various physiological stimuli, such as increase and decrease of the ocular perfusion pressure. The correlation of the subfoveal choroidal blood flow with the anatomical changes of the choroidal circulation, as observed by enhanced depth imaging optical coherence tomography(EDI‐OCT), was investigated in healthy volonteeres. No significant correlation was found between the subfoveal choroidal thickness and the choroidal blood flow. However, decreased subfoveal choroidal thickness was associated with decreased refractive error and axial length.

Choroidal circulation measurements by laser Doppler flux metry

AbstractContinuous real time Laser Doppler Flowmetry (LDF), has been used in humans, for the evaluation of the subfoveal choroidal circulation and the investigation of the regulatory processes of the choroidal blood flow in response to various physiological stimuli, as increases and decreases of the ocular perfusion pressure. A progressive decrease of the choroidal blood flow was observed with the aging and the progession of the age related macular degeneration. Abnormal regulation of the choroidal blood flow in patients suffering with neovascular AMD or Diabétic microangiopathy were also reported. The correlation of the subfoveal choroidal blood flow with the anatomical changes of the choroidal circulation as observed by OCT are under investigation.

This issue of ACTA, printed and electronic

This issue of <i>ACTA</i>, printed and electronic

This issue of Acta, printed and electronic

This issue of Acta, printed and electronic

Choroidal hemodynamic in myopic patients with and without primary open‐angle glaucoma

To investigate the change in subfoveal choroidal blood flow in patients with glaucoma and to assess the effect of myopia, as one of the vascular risk factors for glaucoma on this flow. Subfoveal choroidal blood flow in groups of 12 myopic and glaucomatous eyes has been investigated by means of the laser Doppler flowmetry (LDF), comparing the results with those of 17 myopic eyes without glaucoma, 34 non-myopic glaucomatous eyes and of 50 control eyes. The subfoveal choroidal LDF parameters, that is, blood velocity (ChBVel), volume (ChBVol), and flow (ChBF), as well as the vascular resistance were studied in each group. Statistical analysis was performed by means of anova and t-test according to the Bonferroni procedure for multiple comparisons. Pearson correlation was used to establish the correlations between the hemodynamic parameters and the degree of myopia in dioptres. All LDF parameters (ChBVel, ChBVol and ChBF) were significantly reduced in glaucomatous patients (1.3 ± 0.4, 0.14 ± 0.06 and 4 ± 2 respectively) and myopic patients with primary open-angle glaucoma (POAG) (1.3 ± 0.4, 0.08 ± 0.04 and 2 ± 0.7 respectively) and without POAG (1.2 ± 0.3, 0.11 ± 0.08 and 2 ± 1 respectively) in comparison with age-matched controls (1.5 ± 0.4, 0.27 ± 0.1 and 8 ± 2 respectively). On the other hand, the choroidal vascular resistance (Rm) was increased in the previously described studied patients groups (16 ± 7, 26 ± 9 and 24 ± 9 respectively) compared with controls (7 ± 2). The LDF parameters did not differ significantly between myopic subjects without and with POAG (p = 0.09, p = 0.09, p = 0.2, p = 0.08 and p = 0.9 respectively). Compared to patients with emmetropic glaucomatous, significant reduction in the ChBVol and ChBF and increased Rm were recorded in patients with glaucomatous myopia (p = 0.05, p = 0.04 and p = 0.04 respectively). Pearson correlation demonstrated a significant correlation between the degree of myopia in dioptres and the ChBF (p = 0.012). The subfoveal choroidal LDF parameters were reduced in patients with POAG and myopia. Theses alterations are more in glaucomatous patients with myopia in comparison with age-matched glaucomatous patients without myopia. These data suggest that the impaired choroidal circulation caused by myopia might be an important additional risk factor involved in the glaucomatous damaging process.

Effect of isometric exercise on choroidal blood flow in patients with age-related macular degeneration

AimWe compared the regulatory responses induced by isometric exercise in control subjects and patients with age-related macular degeneration (AMD) to investigate choroidal vascular regulation in AMD.MethodsSeventeen eyes of 17 patients...

Influence of change in body position on choroidal blood flow in patients with obstructive sleep apnea syndrome

Abstract Purpose Obstructive sleep apnea syndrome (OSA) has been reported to be associated with ischemic and glaucomatous optic neuropathy (especially normal tension glaucoma). OSA per se is able to generate hypertension, atherosclerosis and autonomic dysfunction, all conditions possibly interacting with ocular vascular regulation. The aim of our study was to characterize the choroidal vascular reactivity to change in body position in OSA patients, as compared with matched healthy control subjects. Methods Eighteen newly diagnosed OSA patients were included in this prospective study. Control subjects were matched with OSA patients for body mass index (BMI), gender and age. At the screening visit, each subject underwent a general exam, cardiovascular, neurologic and ophthalmological examinations, and overnight polysomnography. The LDF instrument used in this study to measure subfoveal choroidal blood flow (ChBF), ChBVel , velocity (kHz); and volume, ChBVol (in arbitrary units, AU) Vascular choroidal reactivity was tested during the change in body position from the sitting to the supine position (10 min). Results OSA patients exhibited a similar choroidal reactivity during change in body position than controls with increased ChBVel (+15%), decreased ChBVol (‐11.6%), and unchanged ChBF. IOP increased by 14.2% in the supine position whereas ocular perfusion pressure remained stable. Conclusion This prospective comparative study showed for the first time unimpaired choroidal vascular reactivity in otherwise healthy OSA patients. This suggests OSA patients, without comorbidities, has long‐term adaptive mechanisms active in ocular microcirculation.

Choroidal blood flow and retinal ganglion cell function in early glaucoma

Abstract Purpose To assess subfoveal choroidal blood flow in patients with early manifest glaucoma (EMG) and to compare blood flow with functional measures of retinal ganglion cell (RGC) integrity. Methods Subfoveal choroidal blood flow was determined by confocal, real‐time laser Doppler flowmetry in 25 EMG patients (&lt;‐6 dB Humphrey mean deviation, age range: 42‐64 years, visual acuity: 0.8‐1.0) and in 20 age‐matched controls. All patients had a therapeutically (topical beta‐blockers with or without a prostaglandin) controlled intraocular pressure (IOP &lt;20 mmHg). Subfoveal choroidal blood volume (ChBVol), velocity (ChBVel) and flow (ChBF) were determined as the average of three 60 sec recordings with changes in the DC &lt; 10% between the recordings (DC measures the intensity of the light scattered by the tissue and red blood cells in the illuminated volume). In all patients and controls pattern electroretinograms (PERGs) were recorded according to a standardized protocol. Results In EMG patients, average ChBVel and ChBF were reduced by 31 and 35%, respectively (p &lt;0.01) compared to control values. No significant difference in ChBVol was found between the two groups. PERG amplitudes were reduced by 40% (p &lt;0.01) in EMG patients compared to controls. No correlation was found between anyone of the choroidal flow parameters and PERG data or IOP values. Conclusion The results suggest a significant alteration of subfoveal choroidal hemodynamics in EMG patients, involving both ChBVel and ChBF. These changes do not appear to be associated with the severity of functional retinal ganglion cell loss. Our findings may have implications for the pathophysiology of early glaucomatous damage and its treatment.

Effects of Pentoxifylline and Alprostadil on Ocular Hemodynamics in Healthy Humans

Alprostadil, a prostaglandin (PG)E(1) analogue and pentoxifylline, an alkylxanthine derivate, have been shown to exert vasodilatory effects in several vascular beds. The purpose of the present study was to investigate the effect of PGE(1) and pentoxifylline on the ocular circulation. A placebo-controlled, double-masked, three-way, crossover study was performed in 15 healthy male subjects. Subjects received pentoxifylline (300 mg), PGE(1) (alprostadil 60 mug), or placebo intravenously over 2 hours on three trial days. Choroidal red blood cell flow was assessed with laser Doppler flowmetry and pulsatile choroidal blood flow with laser interferometric measurement of fundus pulsation amplitude (FPA). Retinal blood cell flow was calculated based on the measurements of maximum erythrocyte velocity in a retinal vein assessed with bidirectional laser Doppler velocimetry, and diameter measurements of retinal vessels were obtained with a retinal vessel analyzer. Pentoxifylline increased FPA by 15.4% +/- 1.1% (P < 0.001 versus placebo and baseline). Alprostadil tended to increase FPA, but this effect did not reach the level of significance (P = 0.07 versus placebo). Choroidal blood flow as measured with laser Doppler flowmetry tended to increase during pentoxifylline and PGE(1) infusion by 8.9% +/- 2.9% (P = 0.062) and 4.5% +/- 6.2% (P = 0.29), respectively, but none of these effects was significant. The drugs under study had no effect on mean red blood cell velocity in retinal veins, on retinal vessel diameters, intraocular pressure, blood pressure, or pulse rate. PGE(1) did not alter the parameters of retinal or choroidal circulation in healthy subjects. Pentoxifylline increased FPA, but did not change choroidal blood flow as measured with laser Doppler flowmetry and did not affect retinal blood flow parameters. Accordingly, neither pentoxifylline nor PGE(1) appears to be suitable to improve ocular blood flow in healthy subjects. Whether long-term treatment with alprostadil would improve choroidal blood flow in patients with vascular disease remains to be established.

Evaluation of pulsatile choroidal blood flow in branch retinal vein occlusion.

The present study was undertaken to compare pulsatile choroidal blood flow in patients with branch retinal vein occlusion (BRVO) with the values in normal controls. The study included male and female patients with manifest BRVO (n=16) and a healthy sex- and age-matched control group (n=36). Fundus pulsation amplitude (FPA) was measured in the fovea by laser interferometry to assess pulsatile choroidal blood flow. The FPA in eyes with BRVO (4.4 microm) was significantly higher than in the fellow eye (3.8 microm; P<0.0005). There was also a significant difference between the affected eye of the patients and the healthy control group (3.3 microm; P<0.0009). The increase in FPA indicates increased choroidal blood flow resulting from some local mechanisms compensating for the decrease in retinal blood flow.

Indocyanine Green Angiography Patterns of Zones of Relative Decreased Choroidal Blood Flow in Patients With Exudative Age-Related Macular Degeneration

To investigate the incidence and patterns of posterior zones of relative decreased choroidal blood flow in patients with exudative age-related macular degeneration. Digital indocyanine green (ICG) angiograms from 100 patients with exudative age-related macular degeneration were reviewed for the presence of posterior zones of relative decreased choroidal blood flow. The patterns of these zones and their location relative to the choroidal neovascular process were noted. Ninety-five percent of the angiograms displayed the presence of either a complete or an incomplete zone of relative choroidal hypoperfusion. The zone was most apparent in the early frames of the angiogram. Five different patterns of relative decreased choroidal blood flow were identified: horizontal (32%), vertical (14%), bipartite (9%), tripartite (31%), and quadripartite (9%). The choroidal neovascular process was located within or at the edge of the zone of relative choroidal hypoperfusion in all cases. Most cases of choroidal neovascularization localize to areas of relative choroidal dye nonfilling on ICG angiography. These patterns of choroidal nonfilling may have implications in the pathogenesis and management of choroidal neovascular membranes in age-related macular degeneration.