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Purpose: To investigate the alterations of central choroidal thickness (CCT) and macular choroidal blood flow in patients with hypertensive chorioretinopathy treated with antihypertensive agents. Methods: In retrospective observational case series, ten eyes of 9 patients with hypertensive chorioretinopathy were enrolled (5 men and 4 women; 43.1 ± 19.6 years 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. Results: With the medication for hypertension, serous retinal detachment (SRD) disappeared in all the eyes (mean period, 57.8 ± 50.4 days), and the mean blood pressure decreased (122.7 ± 13.0 mmHg and 93.4 ± 13.2 mmHg 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 ± 218.0 μm and 325.7 ± 112.0 μm, P < 0.01). The changing rates of CCT and MBR showed a significant positive correlation (P < 0.01, R = 0.88). Conclusion: 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. [ABSTRACT FROM AUTHOR]

Purpose: On the basis of angiographic features, it is suggested that choroidal circulation disturbance may be involved in the pathogenesis of multiple evanescent white dot syndrome (MEWDS). The aim of this study is to quantitatively evaluate changes in choroidal circulation hemodynamics using laser speckle flowgraphy (LSFG) in patients with MEWDS. Methods: Twelve eyes of 12 patients with MEWDS and 12 unaffected fellow eyes as controls were included. The macular mean blur rate (MBR), a quantitative index of relative blood flow velocity in the choroid, was measured by LSFG. Sequential changes in the average MBR values at the macula with granular changes and the lesion area with white dots were analysed. Moreover, correlations between the MRR changing rate and initial visual functions were examined. Results: Visual functions significantly improved 3 months after initial visit with accompanying improvements in outer retinal morphology. When compared with the baseline measurements, the MBR significantly increased at the macula of the affected eyes by 20.2 % and 13.0 % at 1 and 3 months respectively ( P < 0.01 for both), while no significant change was detected in fellow eyes. Similarly, the MBR increased at the lesion area by 17.8 % and 12.0 % at 1 and 3 months respectively ( P < 0.05 for both). Notably, the macular MBR elevation at 1 month was negatively correlated with both initial best-corrected visual acuity and the average threshold at the macula on Humphrey perimetry at baseline ( R = −0.76, P = 0.003; R = −0.60, P = 0.03, respectively), suggesting a close link between initially reduced choroidal blood flow and functional abnormalities at the onset of MEWDS. Conclusions: These results, in concert with angiographic findings, are likely to reinforce the concept of choroidal circulation impairment as a predisposing factor for MEWDS. [ABSTRACT FROM AUTHOR]

It is unclear whether exhaustive dynamic exercise increases ocular blood flow, although we have reported that submaximal exercise increases ocular blood flow. We hypothesized that ocular blood flow decreases at exhaustion, since exhaustion causes hyperventilation, which induces a reduction in PaCO. To test this hypothesis, ocular blood flow, blood pressure, and respiratory measurements were made in 12 healthy male subjects during cycle ergometer exercise at 75% of maximal heart rate, until exhaustion. Blood flows in the retinal and choroidal vasculature (RCV), the superior temporal retinal arteriole (STRA), and the superior nasal retinal arteriole (SNRA) were measured with the aid of laser-speckle flowgraphy every 3 min during the exercise. The conductance index (CI) in the ocular vasculature was calculated by dividing the blood flow by the mean arterial pressure (MAP). The mean arterial partial pressure of CO ( PaCO) was estimated from tidal volume and end-tidal CO partial pressure. MAP significantly increased from the resting baseline throughout the exercise, while PaCO was significantly decreased at exhaustion and during the recovery period. By 6 min after the onset of exercise, blood flow velocity in the RCV significantly increased by 32 ± 6% (mean ± SD) from the resting baseline value. At exhaustion, blood flow velocity in the RCV did not differ significantly from the resting baseline value, and the STRA blood flow was significantly decreased by 13 ± 4%. The CIs in the RCV, STRA, and SNRA were significantly decreased compared to baseline at exhaustion. These findings suggest that ocular blood flow is increased by submaximal exercise, whereas it is suppressed by the hypocapnia associated with exhaustion. [ABSTRACT FROM AUTHOR]

Background: Birdshot chorioretinopathy, acute posterior multifocal placoid pigment epitheliopathy, and retinal pigment epithelial detachment have been reported as rare manifestations associated with sarcoidosis, suggesting that ocular sarcoidosis may affect the choroidal circulation. We report a case of ocular sarcoidosis representing a choroidal circulatory disturbance without the appearance of retinal lesions or loss of retinal function. Case: A 20-year-old woman was referred with blurred vision in the left eye. Inflammatory change in the anterior segment of the eye was noted with multiple nodules on the iris. Observations: Hematological examination revealed elevated lysozyme levels. Bilateral hilar lymphadenopathy was noted on chest X-ray. Specimens obtained by transbronchial lung biopsy revealed granuloma with Langhans giant cells, which led to the diagnosis of sarcoidosis. The eye was treated with topical steroid. The symptoms and the inflammatory change in the anterior segment disappeared within 10 days. However, despite the normal appearance of the ocular fundus, fluorescein angiography revealed multiple puncta of hyperfluorescence. In indocyanine green angiography, a filling delay was noted in the area corresponding to the punctate lesions. Static visual field testing and multifocal electroretinography showed no significant changes. At the last visit, 15 months after the left eye became asymptomatic, the choroidal lesions had disappeared with no residual alteration of the funduscopic appearance or visual function. Conclusions: This case indicates that choroidal circulatory disturbance can underlie ocular sarcoidosis even in the absence of funduscopically detectable lesions and loss of visual function. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effects of felodipine, a calcium channelblocker, on ocular circulation. Methods: In a double blind, randomized,crossover design, 10 volunteers received placebo or felodipine on 2 separatedays. Bidirectional laser Doppler velocimetry (BLDV), laser Doppler flowmetry(LDF), and monochromatic fundus photography (MFP) were employed to assessretinal, choroidal, and optic nerve rim circulatory parameters. Measurements wereobtained at baseline, 1.5, and 3 hours after dosing. Blood pressure, intraocularpressure (IOP), and heart rate were monitored, and perfusion pressure (PP) wascalculated. Results: In comparison to placebo, significant average percentagedecreases in diastolic blood pressure (BPd; p = 0.001), mean blood pressure (BPm;p = 0.003), and perfusion pressure (PP; p = 0.003) were observed 1.5 hours following felodipine. No significant differences were observed following placebo. Retinal, choroidal and optic nerve rim circulatory parameters showed no significant changes after placebo or felodipine. A significant positive correlation between BPd and optic nerve velocity (ONvel) was observed 3 hours following felodipine (R = +0.654; p = 0.040). In contrast, no significant correlation between BPd and ONvel was noted (R = +0.198; p = 0.583) following placebo. Conclusions: No significant change in retinal, optic nerve rim, or foveolar choroidal blood flow were observed, a factor that may be important in the treatment of systemic hypertension in patients with glaucoma. Abbreviations:BLDV – Bidirectional laser Doppler velocimetry;BPd – diastolic blood pressure;BPm – mean blood pressure;BPs – systolic blood pressure;CHflow – choroidal flow;CHvel – choroidal velocity;CHvol – choroidal volume;D – vessel diameter;LDF – Laser Doppler flowmetry;MFP – monochromatic fundus photography;ONflow – optic nerve flow;ONvel – optic nerve velocity;ONvol – optic nerve volume;PP – perfusion pressure;Q – retinal volumetric blood flow rate;Vmax – maximum velocity of whole blood;Vmean – mean velocity of whole blood. [ABSTRACT FROM AUTHOR]