Changes in choroidal tissue post-supplementation with vitamin D in pediatric patients who are deficient in vitamin D.

PURPOSE: To quantitatively assess the choroidal structural parameters of patients in the pediatric age group who were deficient in vitamin D [Vit-D] pre- and post-treatment. DESIGN: Prospective, case-control study. METHODS: Choroidal structural parameters, including the choroidal thickness (CT) at five points, total choroidal area (TA), luminal choroidal area (LA), stromal choroidal area (SA), and choroidal vascular index (CVI), in patients in the pediatric age group who were deficient in Vit-D, in Group 1, and those who were not, in Group 2, were compared. The patients were divided into 3 different groups according to how deficient in Vit-D they were. This was re-evaluated after treatment. RESULTS: Group 1 consisted of 83 patients and group 2 consisted of 85 patients. CT at all five points, and the TA, SA, LA, and CVI, were lower in Group 1. And for all of these, a significant increase was seen post-treatment. While a significant increase was observed in all of the values in the group with the most severe deficiency in Vit-D, significant changes were observed in the TA, LA, SA, and CVI values in the group that was mildly deficient in Vit-D. There was no significant post-treatment value in the CT values (except for the Temporal 1500 CT [P = 0.012]). CONCLUSION: Decreases in the CT, TA, LA, SA, and CVI were among the structural changes that were seen to occur in the pediatric patient group that was deficient in Vit-D. Moreover, thinning of the choroid and a decrease in the CVI were the most significant in the group with the greatest Vit-D deficiency.

The effect of hyperbaric oxygen therapy on retina, choroidal thickness, and choroidal vascularity index.

PURPOSE: To determine the acute and cumulative effect of hyperbaric oxygen therapy (HBOT) on retina and choroid tissue in healthy eyes. MATERIAL AND METHODS: Thirty-five subjects who were planned to undergo HBOT for non-ophthalmologic indications comprised the population of this prospective study. Central macular thickness (CMT), retinal nerve fiber layer (RNFL), and choroidal thickness (CT) (3 points: subfoveal area, 500 µm nasal and fovea temporal) were measured using spectral-domain optical coherence tomography (SD-OCT) before HBOT and half an hour after the 1st and 20th sessions of HBOT. The subfoveal choroidal area was segmented using ImageJ software with the binarization technique on enhanced depth imaging (EDI) OCT images. Choroidal area (CA), luminal area (LA), and stromal area (SA) were calculated. Choroidal vascularity index (CVI) was determined as the ratio between LA and CA. RESULTS: The right eyes of 35 patients aged between 22 and 59 years were enrolled in the study. The mean CMT values of the patients were 259.36 ± 22.31 µm, 256.94 ± 22.72 µm, and 254.58 ± 23.02 µm before HBOT, after the 1st session, and after the 20th session, respectively. The change in CMT values before and after HBOT was statistically significant (p=0.001). When the patients' RNFL, CT, CA, SA, LA, and CVI changes before and after the HBOT were examined, no statistically significant difference was found (p>0.05). CONCLUSIONS: Our study jointly evaluates the effect of HBOT on the vascular and stromal components of the choroid and macula in healthy eyes. Due to its thinning effect on the macula, it can be preferred as an adjunctive and facilitating treatment option in addition to current treatments in patients with macular edema due to retinal vascular disorders.

Dietary ω-3 polyunsaturated fatty acids are protective for myopia.

Myopia is a leading cause of visual impairment and blindness worldwide. However, a safe and accessible approach for myopia control and prevention is currently unavailable. Here, we investigated the therapeutic effect of dietary supplements of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) on myopia progression in animal models and on decreases in choroidal blood perfusion (ChBP) caused by near work, a risk factor for myopia in young adults. We demonstrated that daily gavage of ω-3 PUFAs (300 mg docosahexaenoic acid [DHA] plus 60 mg eicosapentaenoic acid [EPA]) significantly attenuated the development of form deprivation myopia in guinea pigs and mice, as well as of lens-induced myopia in guinea pigs. Peribulbar injections of DHA also inhibited myopia progression in form-deprived guinea pigs. The suppression of myopia in guinea pigs was accompanied by inhibition of the "ChBP reduction-scleral hypoxia cascade." Additionally, treatment with DHA or EPA antagonized hypoxia-induced myofibroblast transdifferentiation in cultured human scleral fibroblasts. In human subjects, oral administration of ω-3 PUFAs partially alleviated the near-work-induced decreases in ChBP. Therefore, evidence from these animal and human studies suggests ω-3 PUFAs are potential and readily available candidates for myopia control.

Changes in Choroidal Component Ratio and Circulation After Coffee Intake in Healthy Subjects.

Purpose: The effects of coffee intake on the ratio of stromal and luminal components in the choroid and the underlying mechanism remain unclear. This prospective cross-sectional study aimed to explore how coffee intake affects the choroidal component ratio and circulation. Methods: Forty-nine right eyes of healthy adult volunteers were evaluated as the coffee intake group. Thirty-two right eyes of healthy volunteers served as the control group. The participants consumed 185 mL of coffee or water, respectively, and the systemic hemodynamics, enhanced-depth imaging optical coherence tomographic (EDI-OCT) images, and foveal mean blur rate (MBR), an indicator of blood flow velocity, were recorded at baseline and after coffee or water intake. The EDI-OCT images were binarized using ImageJ software, and subfoveal choroidal thickness (SCT) and whole, luminal, and stromal choroidal areas were calculated. Results: In the coffee intake group, significant decreases in SCT and luminal area peaked at 60 minutes after intake (both P < 0.001), whereas a significant increase in MBR peaked at 30 minutes (P < 0.001). No significant stromal area fluctuations were observed. SCT and luminal area fluctuations exhibited a significant positive correlation (r = 0.978, P < 0.001). Significant negative correlations of luminal area fluctuations with MBR fluctuations were observed by stepwise regression analysis (r = -0.220, P < 0.001). The control group exhibited no significant fluctuations. Conclusions: Coffee-induced choroidal thinning may result mainly from a reduction in the choroidal vessel lumen, and this vessel lumen reduction correlated with an increased choroidal blood flow velocity after coffee intake. These coffee-induced changes in choroidal component ratio and circulation should be considered when evaluating choroids.

Chebulagic acid and Chebulinic acid inhibit TGF-ß1 induced fibrotic changes in the chorio-retinal endothelial cells by inhibiting ERK phosphorylation.

PURPOSE: Diabetic retinopathy (DR) is characterized by pro-inflammatory, pro-angiogenic and pro-fibrotic environment during the various stages of the disease progression. Basement membrane changes in the retina and formation of fibrovascular membrane are characteristically seen in DR. In the present study the effect of Alcoholic (AlE) extracts of Triphala an ayurvedic herbal formulation and its chief compounds, Chebulagic (CA), Chebulinic (CI) and Gallic acid (GA) were evaluated for TGFß1-induced anti-fibrotic activity in choroid-retinal endothelial cells (RF/6A). METHOD: RF/6A cells were treated with TGFß1 alone or co-treated with AlE, CA, CI or GA. The mRNA and protein expression of fibrotic markers (αSMA, CTGF) were assessed by qPCR and western blot/ELISA. Functional changes were assessed using proliferation assay and migration assay. To deduce the mechanism of action, downstream signaling was assessed by western blot analysis along with in silico docking studies. RESULT: AlE (50 µg/ml) CA and CI at 10 µM reduced the expression of pro-fibrotic genes (αSMA and CTGF) induced by TGFß1, by inhibiting ERK phosphorylation. GA did not inhibit TGFß1 mediated changes in RF/6A cells. In silico experiments shows that CA and CI has favourable binding energy to bind with TGFß receptor and inhibit the downstream signaling, while GA did not. CONCLUSION: Hence this study identifies Triphala and its chief compounds CA and CI as potential adjuvants in the management of DR.

Changes in choriocapillaris and retinal morphology after laser photocoagulation by OCT angiography: A case report.

RATIONALE: Earlier studies have shown that laser photocoagulation treatments are associated with good long-term visual acuity in most patients with severe nonproliferative diabetic retinopathy (S-NPDR). Histopathologic studies of autopsied eyes have demonstrated defects in the choriocapillaris beneath the retinal laser lesions secondary to photocoagulation for S-NPDR. These lesions have been observed to expand centrifugally over time especially in the posterior pole, and the atrophy of the retinal pigment epithelium (RPE) can be significantly enlarged. There are, however, limited studies detailing the in vivo changes that occur in the RPE and choriocapillaris following laser photocoagulation. PATIENT CONCERNS: A 46-year-old woman presented with visual disturbances in both eyes. DIAGNOSES: Fundus examinations showed many retinal hemorrhages and soft exudates in the four quadrants due to S-NPDR. INTERVENTIONS: Laser photocoagulations with a 532-nm wavelength argon laser with power of 170 to 230 mW and spot size of 200 µm were performed to treat the S-NPDR. The changes in the choriocapillaris and retinal vasculature were followed by optical coherence tomography (OCT) angiography. OUTCOMES: The choriocapillaris beneath the laser spots was disrupted from 1 hour following the photocoagulation but it was restored at week 2. The choriocapillaris appeared almost normal at some laser spots, but they were still some spots that were altered at 1 year. The outer retina and RPE were disrupted beneath the laser spots at 1 year. On the contrary, there were no visible retinal vascular changes in the superficial and deep plexuses of retinal vasculature determined by OCT angiography with manual and automated segmentation. LESSONS: The choriocapillaris in human eyes can recover after laser photocoagulation although the outer retina and RPE remain disrupted and do not recover.

Stereological Method in Optical Coherence Tomography for In Vivo Evaluation of Laser-Induced Choroidal Neovascularization.

BACKGROUND AND OBJECTIVE: To evaluate a stereological method in optical coherence tomography (OCT) as an in vivo volume measurement of laser-induced choroidal neovascularization (L-CNV) lesion size. PATIENTS AND METHODS: Laser photocoagulation was applied in rats to rupture Bruch's membrane and induce L-CNV. In vivo OCT images of neovascular lesions were acquired with a spectral-domain OCT system at days 0, 3, 7, 10, and 14 after laser surgery. A stereological image-processing method was used to calculate lesion volumes from the OCT images. Rats were euthanized at day 14, and confocal microscopy was used to obtain accurate volume measurements of the lesions ex vivo. Lesion sizes calculated from OCT and confocal were compared. RESULTS: In vivo assessment by OCT allowed three distinct stages of L-CNV to be visualized: the initial early reaction, neovascular proliferation, and regression. At day 14, correlations between OCT and confocal lesion volumes showed a positive association (Pearson's r = 0.50, P < .01). Except for the largest lesions, volumes measured by OCT were statistically similar to those measured by the confocal gold standard (P = .90). CONCLUSION: The stereological approach used to measure neovascular lesion volume from OCT images offers an accurate means to track L-CNV lesion size in vivo. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:e65-e74.].

Targeted Intraceptor Nanoparticle for Neovascular Macular Degeneration: Preclinical Dose Optimization and Toxicology Assessment.

Neovascular age-related macular degeneration (AMD) is treated with anti-VEGF intravitreal injections, which can cause geographic atrophy, infection, and retinal fibrosis. To minimize these toxicities, we developed a nanoparticle delivery system for recombinant Flt23k intraceptor plasmid (RGD.Flt23k.NP) to suppress VEGF intracellularly within choroidal neovascular (CNV) lesions in a laser-induced CNV mouse model through intravenous administration. In the current study, we examined the efficacy and safety of RGD.Flt23k.NP in mice. The effect of various doses was determined using fluorescein angiography and optical coherence tomography to evaluate CNV leakage and volume. Efficacy was determined by the rate of inhibition of CNV volume at 2 weeks post-treatment. RGD.Flt23k.NP had peak efficacy at a dose range of 30-60 µg pFlt23k/mouse. Using the lower dose (30 µg pFlt23k/mouse), RGD.Flt23k.NP safety was determined both in single-dose groups and in repeat-dose (three times) groups by measuring body weight, organ weight, hemoglobin levels, complement C3 levels, and histological changes in vital organs. Neither toxicity nor inflammation from RGD.Flt23k.NP was detected. No side effect was detected on visual function. Thus, systemic RGD.Flt23k.NP may be an alternative to standard intravitreal anti-VEGF therapy for the treatment of neovascular AMD.

Anti-angiogenic effect of ALS-L1023, an extract of Melissa officinalis L., on experimental choroidal neovascularization in mice.

BACKGROUND: The effect of ALS-L1023, an extract of Melissa officinalis L. (Labiatae; lemon balm) leaves, on experimental choroidal neovascularization (CNV) in mice was evaluated. METHODS: C57BL/6 mice were given either vehicle or ALS-L1023 daily via oral gavage for 3 weeks (days 0-21). CNV was induced by rupturing Bruch's membrane using laser photocoagulation (day 7). Two weeks after laser injury (day 21), the CNV lesions were evaluated by an examination of choroidal flat mounts using fluorescein-labelled dextran, immunofluorescence staining with isolectin B4 and fluorescence angiography. The effects of ALS-L1023 on endothelial cell tube formation and the expression of phosphorylated extracellular signal-regulated kinase 1/2 were evaluated using human umbilical vein endothelial cells. RESULTS: The extent of CNV was reduced by ALS-L1023. Mice treated with 100 and 200 mg/kg/day of the material exhibited 44.3 and 68.1% reductions in the extent of CNV lesions, respectively, compared to the vehicle group (P < 0.001). The size of the isolectin B4-labelled area was also significantly decreased in the ALS-L1023-treated groups (P < 0.001). On fluorescein angiography, ALS-L1023-treated mice exhibited significantly less leakage of fluorescent material than did vehicle-treated mice. ALS-L1023 decreased vascular endothelial growth factor-induced human umbilical vein endothelial cell tube formation in a dose-dependent manner. The expression of phosphorylated extracellular signal-regulated kinase 1/2 was suppressed by ALS-L1023. CONCLUSIONS: The laser-induced CNV in mice can be inhibited by ALS-L1023. Therefore, it may have therapeutic potential for the treatment of diseases involving CNV.

Melissa officinalis extract inhibits laser-induced choroidal neovascularization in a rat model.

PURPOSE: This study investigated the effect of Melissa officinalis extract on laser-induced choroidal neovascularization (CNV) in a rat model. The mechanism by which M. officinalis extract acted was also investigated. METHODS: Experimental CNV was induced by laser photocoagulation in Brown Norway rats. An active fraction of the Melissa leaf extract was orally administered (50 or 100 mg/kg/day) beginning 3 days before laser photocoagulation and ending 14 days after laser photocoagulation. Optical coherence tomography and fluorescein angiography were performed in vivo to evaluate the thickness and leakage of CNV. Choroidal flat mount and histological analysis were conducted to observe the CNV in vitro. Vascular endothelial growth factor (VEGF), matrix metalloproteinase (MMP)-2, and MMP-9 expression were measured in retinal and choroidal-scleral lysates 7 days after laser injury. Moreover, the effect of M. officinalis extract on tertiary-butylhydroperoxide (t-BH)-induced VEGF secretion and mRNA levels of VEGF, MMP-2, and MMP-9 were evaluated in human retinal epithelial cells (ARPE-19) as well as in human umbilical vein endothelial cells (HUVECs). RESULTS: The CNV thickness in M. officinalis-treated rats was significantly lower than in vehicle-treated rats by histological analysis. The CNV thickness was 33.93±7.64 µm in the high-dose group (P<0.001), 44.09±12.01 µm in the low-dose group (P = 0.016), and 51.00±12.37 µm in the control group. The proportion of CNV lesions with clinically significant fluorescein leakage was 9.2% in rats treated with high-dose M. officinalis, which was significantly lower than in control rats (53.4%, P<0.001). The levels of VEGF, MMP-2, and MMP-9 were significantly lower in the high-dose group than in the control group. Meanwhile, M. officinalis extract suppressed t-BH-induced transcription of VEGF and MMP-9 in ARPE-19 cells and HUVECs. CONCLUSIONS: Systemic administration of M. officinalis extract suppressed laser-induced CNV formation in rats. Inhibition of VEGF and MMP-9 via anti-oxidative activity may underlie this effect.

Effect of choroidal blood perfusion and natural convection in vitreous humor during transpupillary thermotherapy (TTT).

During retinal surgical treatment often the gel-like vitreous humor is replaced by aqueous substitutes. A two-dimensional computational model is developed for simulating transpupillary thermotherapy (TTT) process in a human eye under post-retinal treatment. The model accounts for natural convection in vitreous humor and the choroidal blood perfusion. Time dependent and steady state forms of Pennes bio heat transfer and the natural convection governing energy equations are solved using finite volume formulation. The results for steady state and at the end of 60 s of the laser irradiated TTT process show that flow in vitreous humor is significant. The velocity contours indicate strong natural convection on the upper half of the vitreous chamber. Compared with the stationary vitreous case, the peak temperature in retina during TTT, drops by 15 K and 12.5 K due to natural convection flow in the vitreous humor under steady and transient states, respectively. The choroidal blood perfusion also reduces the peak retinal temperature by 6 K and 1.5 K in steady state and transient cases, respectively. The vitreous humor convection enhances heat transfer in the regions adjacent to the laser spot. The temperature rise and the associated thermal damage in the neighboring regions resulting from the flow of vitreous humor is presented.

Dynamic increase in extracellular ATP accelerates photoreceptor cell apoptosis via ligation of P2RX7 in subretinal hemorrhage.

Photoreceptor degeneration is the most critical cause of visual impairment in age-related macular degeneration (AMD). In neovascular form of AMD, severe photoreceptor loss develops with subretinal hemorrhage due to choroidal neovascularization (CNV), growth of abnormal blood vessels from choroidal circulation. However, the detailed mechanisms of this process remain elusive. Here we demonstrate that neovascular AMD with subretinal hemorrhage accompanies a significant increase in extracellular ATP, and that extracellular ATP initiates neurodegenerative processes through specific ligation of Purinergic receptor P2X, ligand-gated ion channel, 7 (P2RX7; P2X7 receptor). Increased extracellular ATP levels were found in the vitreous samples of AMD patients with subretinal hemorrhage compared to control vitreous samples. Extravascular blood induced a massive release of ATP and photoreceptor cell apoptosis in co-culture with primary retinal cells. Photoreceptor cell apoptosis accompanied mitochondrial apoptotic pathways, namely activation of caspase-9 and translocation of apoptosis-inducing factor (AIF) from mitochondria to nuclei, as well as TUNEL-detectable DNA fragmentation. These hallmarks of photoreceptor cell apoptosis were prevented by brilliant blue G (BBG), a selective P2RX7 antagonist, which is an approved adjuvant in ocular surgery. Finally, in a mouse model of subretinal hemorrhage, photoreceptor cells degenerated through BBG-inhibitable apoptosis, suggesting that ligation of P2RX7 by extracellular ATP may accelerate photoreceptor cell apoptosis in AMD with subretinal hemorrhage. Our results indicate a novel mechanism that could involve neuronal cell death not only in AMD but also in hemorrhagic disorders in the CNS and encourage the potential application of BBG as a neuroprotective therapy.

Pattern of blood vessels in eyes with coloboma.

BACKGROUND: Choroidal coloboma, especially with optic disc involvement affects the blood vessel (BV) pattern in the fundus. AIM: The aim of this study was to report the observations on the pattern of retinal BVs in eyes with fundus coloboma. DESIGN: Retrospective observational study. MATERIALS AND METHODS: Twenty four eyes of 19 patients with fundus coloboma and the disc involvement in the coloboma was classified according to a previous publication. RESULTS: Four varieties of BVs were identified in the area of coloboma - BVs that were continuous with those arising from the optic disc; vessels emanating from the floor of coloboma whose continuity with central retinal artery or its branches could be indirectly established; and those emanating from the floor of coloboma whose continuity with central retinal artery could not be established. In addition, extraocular BVs were visible through the thinned sclera. The retinal BVs often traversed the coloboma to reach the normal retina. The disc itself was found to be small and had no physiological cup (if not colobomatous). CONCLUSIONS: One should be aware of the major BVs transgressing the coloboma while performing relaxing cuts in the intercalary membrane, during the surgery for retinal detachments in eyes with coloboma. Physiological cup is usually absent (when the disc is not colobomatous). Hence, any cupping in such eyes should be viewed with suspicion.

Hyperglycaemia exacerbates choroidal neovascularisation in mice via the oxidative stress-induced activation of STAT3 signalling in RPE cells.

Choroidal neovascularisation (CNV) that occurs as a result of age-related macular degeneration (AMD) causes severe vision loss among elderly patients. The relationship between diabetes and CNV remains controversial. However, oxidative stress plays a critical role in the pathogenesis of both AMD and diabetes. In the present study, we investigated the influence of diabetes on experimentally induced CNV and on the underlying molecular mechanisms of CNV. CNV was induced via photocoagulation in the ocular fundi of mice with streptozotocin-induced diabetes. The effect of diabetes on the severity of CNV was measured. An immunofluorescence technique was used to determine the levels of oxidative DNA damage by anti-8-hydroxy-2-deoxyguanosine (8-OHdG) antibody, the protein expression of phosphorylated signal transducer and activator of transcription 3 (p-STAT3) and vascular endothelial growth factor (VEGF), in mice with CNV. The production of reactive oxygen species (ROS) in retinal pigment epithelial (RPE) cells that had been cultured under high glucose was quantitated using the 2',7'-dichlorofluorescein diacetate (DCFH-DA) method. p-STAT3 expression was examined using Western blot analysis. RT-PCR and ELISA processes were used to detect VEGF expression. Hyperglycaemia exacerbated the development of CNV in mice. Oxidative stress levels and the expression of p-STAT3 and VEGF were highly elevated both in mice and in cultured RPE cells. Treatment with the antioxidant compound N-acetyl-cysteine (NAC) rescued the severity of CNV in diabetic mice. NAC also inhibited the overexpression of p-STAT3 and VEGF in CNV and in RPE cells. The JAK-2/STAT3 pathway inhibitor AG490 blocked VEGF expression but had no effect on the production of ROS in vitro. These results suggest that hyperglycaemia promotes the development of CNV by inducing oxidative stress, which in turn activates STAT3 signalling in RPE cells. Antioxidant supplementation helped attenuate the development of CNV. Thus, our results reveal a potential strategy for the treatment and prevention of diseases involving CNV.

An experimental study of a modified dahuang zhechong pill on the--angiogenesis of RF/6A cells in vitro.

OBJECTIVE: To investigate the effects of a modified Dahuang Zhechong Pill (MDZP) on the angiogenesis of rhesus choroid-retina endothelial (RF/6A) cells and its preliminary mechanism. METHODS: A 3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) method was used to assess the effect of a MDZP on RF/6A cell proliferation induced by vascular endothelial growth factor (VEGF). Transwell inserts were used to assess the effect of the MDZP on RF/6A cell migration. Matrigel was used to assess the effect of the MDZP on the tube formation of RF/ 6A cells. Western blotting and quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) were used to detect the protein and mRNA expression, respectively, of VEGF and matrix metalloproteinase-2 (MMP-2) in RF/6A cells treated with the MDZP. RESULTS: RF/6A cell proliferation induced by VEGF was inhibited by 0.2 mg/mL MDZP. At 0, 12.5, 25 and 50 mg/mL MDZP, the number of cells that migrated through Transwell membranes was 73.33 +/- 4.51, 61.33 +/- 4.04, 28.67 +/- 6.66 and 17.67 +/- 4.16, respectively, and the number of tubes formed in Matrigel was 20.33 +/- 0.58, 13.33 +/- 1.53, 11.00 +/- 1.00 and 1.33 +/- 0.58, respectively. At 100 and 200 mg/mL MDZP, the protein and mRNA expression of VEGF and MMP-2 were inhibited in RF/6A cells. At 400 mg/mL MDZP, the expression of VEGF mRNA and MMP-2 protein were inhibited in RF/6A cells. CONCLUSIONS: MDZP inhibits the angiogenesis of RF/6A cells via the suppression of proliferation, migration and tube formation of RF/6A cells. Inhibition of the protein and mRNA expression of VEGF and MMP-2 in RF/6A cells may be an important mechanism.

Microcirculation patterns in indocyanine green angiography and the results of plaque therapy in choroidal melanoma.

PURPOSE: To determine the effect of radioactive plaque therapy on blood vessel behaviour in choroidal melanomas using indocyanine green (ICG) angiography. MATERIAL AND METHODS: Fifty-five patients with choroidal melanoma were studied. Ruthenium-106 plaques were used in 30 eyes, in 11 the "sandwich method" (Ruthenium-106 plaque with transpupillary thermotherapy), was applied and 14 tumours were treated with Iodine-125. In all cases ICG angiography was performed prior to treatment and 12 months after, and at different time afterwards. Baseline tumour microcirculation patterns (MCPs) were studied prior to treatment and post-treatment blood vessels changes were evaluated. Total follow-up period ranged from 14-22 months (mean: 16 months). RESULTS: Pre-treatment ICG angiography revealed complex MCPs, combining parallel with cross-linking, arcs with branching, loops and networks patterns in 23 (41.8%) and non-complex MCPs, including straight, parallel without cross-linking and arcs without branching patterns in 32 (58.2%) melanomas. Twelve months after treatment, 38 tumours (69.1%) showed a significant changes in their MCPs. The mean ultrasonographic regression rate in tumours with complex MCPs was 57.4% as opposed to 36.2% in the group with non-complex MCPs (p = 0.01). No statistically significant correlation in the height regression rate was found among the various methods of therapy, however a significant difference between the type of therapy and MCPs changes was observed (p < 0.001). Melanomas treated with Ruthenium-106 and TTT demonstrated slight or no MCPs changes, while tumours treated with Ruthenium-106 and Iodine-125 plaques alone showed a significant MCPs changes (p < 0.001). The statistical analysis showed the correlation between the type of baseline MCPs and the degree of their changes after treatment (p < 0.001). Tumours with networks, loops, arcs with branching and parallel with crossing showed an increased regression as compared to other MCPs. Twelve patients whose tumours contained complex MCPs developed metastatic disease. CONCLUSIONS: This study suggests that the response of choroidal melanoma to irradiation is related to MCPs as identified by ICG angiography; the presence of complex MCPs is associated with a high regression rate after plaque therapy and a high risk of development of systemic metastatic disease.

Long-term choroidal vascular changes after iodine brachytherapy versus transpupillary thermotherapy for choroidal melanoma.

PURPOSE: To compare long-term choroidal vascular changes after iodine-125 brachytherapy (IBT) versus transpupillary thermotherapy (TTT) used as primary treatment of small choroidal melanoma. METHODS: Ninety-five small choroidal melanomas were randomized: 49 eyes with TTT and 46 eyes with IBT alone. Fluorescein and indocyanine green angiography (ICGA) were performed at 3-month intervals during the first year, and every 6 months thereafter. RESULTS: Mean follow-up was 56.2 months (range, 24-118 months; SD, 22.6). Tumor regressed in 45 (92%) TTT-treated vs 45 (98%) IBT-treated eyes (p=0.397). Four TTT-treated and one IBT-treated tumor recurred. Occlusion of choriocapillaris was present in all TTT and IBT cases. Closure of medium and large choroidal vessels was observed in 17 (35%) TTT-treated vs 44 (96%) IBT-treated eyes (p<0.001). Choroidal vascular remodeling was detected in 20 (41%) TTT-treated and 16 (35%) IBT-treated eyes (p=0.693). Retinochoroidal anastomosis was present in 4 of the 37 (11%) TTT-treated eyes with patency of medium and large choroidal vessels, but never observed in the IBT-treated eyes, and was associated with tumor recurrence. Among IBT-treated eyes, segments of choroidal vascular wall ICG staining and choroidal aneurysmal changes were detected in 30 (65%) and 7 (15%), respectively. These changes were never detected in TTT-treated cases (p<0.0001 and p=0.015, respectively). CONCLUSIONS: The pattern of tumor choroidal vascular changes following IBT and TTT differs. TTT is less effective in closing all tumor vasculature. The role of long-term choroidal vascular remodeling observed after these two treatments needs longer follow-up.

A placebo-controlled 3-year study of a calcium blocker on visual field and ocular circulation in glaucoma with low-normal pressure.

PURPOSE: To study the 3-year effect of oral nilvadipine, a calcium antagonist, on visual field performance and ocular circulation in open-angle glaucoma (OAG) with low-normal intraocular pressure (IOP). DESIGN: A randomized, placebo-controlled, double-masked, single-center trial. PARTICIPANTS: Patients with OAG who were younger than 65 years and had untreated IOP consistently of 16 mmHg or less. INTERVENTION: Oral nilvadipine (2 mg twice daily) or placebo was assigned randomly to patients fulfilling the criteria by the minimization method of balancing the groups according to age, refraction, and the mean deviation (MD) value (Humphrey Perimeter 30-2 SITA Standard Program; Humphrey Instruments, Inc., San Leandro, CA) of the eye with less negative MD. No topical ocular hypotensive drugs were prescribed. Visual field testing was performed every 3 months; fundus examination and IOP, blood pressure, and pulse rate measurements were carried out every month; and quantitative indexes of circulation in the optic disc rim (NB(ONH)) and choroid in the foveal area (NB(fovea)) were determined using the laser speckle method at 0, 3, 6, 12, 18, 24, 30, and 36 months. MAIN OUTCOME MEASURES: The time courses of MD, NB(ONH), and NB(fovea) in the eye with less negative MD. RESULTS: Thirty-three patients were enrolled; 17 were assigned to nilvadipine and 16 were assigned to placebo; 13 in each group completed the study. No significant intergroup difference was seen in age, refraction, or baseline values of any of the parameters. During the 3-year period, the IOP averaged 12.6 mmHg in the nilvadipine group and 12.8 mmHg in the placebo group (P>0.1), and no significant change from baseline or intergroup difference was seen in blood pressure or pulse rate. The estimated slope of change in the MD was less negative in the nilvadipine than in the placebo group (-0.01 vs. -0.27 decibels/year; P = 0.040). The NB(ONH) and NB(fovea) values remained increased compared with baseline for the study period by approximately 30% to 40% only in the nilvadipine group, and the intergroup difference was significant (P = 0.003 for NB(ONH) and P = 0.007 for NB(fovea)). CONCLUSIONS: Nilvadipine (2 mg twice daily) slightly slowed the visual field progression and maintained the optic disc rim, and the posterior choroidal circulation increased over 3 years in patients with OAG with low-normal IOP.

[Choroidal vessels alterations in treated and untreated diabetic rats]. / Alterações vasculares na coróide de ratos diabéticos tratados e não tratados.

PURPOSE: To evaluate the diabetic alterations and the impact of short and long-term medical treatment on them. METHODS: Thirty Wistar rats were divided into 3 groups: control (GC), diabetic (DG), and treated diabetic (TG) and the observations were made 1 month (M1) and 12 months (M2) after diabetes induction. Diabetes was induced by intravenous alloxan (42 mg/kg). The treated group received acarbose orally and insulin by subcutaneous injection. Eyes were prepared for transmission electron microscopy, specifically for ultrastructure of the Bruch membrane and choroidal vessels. RESULTS: Ultrastructural examination of the diabetic rat choroid showed deposits in the Bruch membrane and accumulation of vesicles, glycogen and dense bodies in endothelial cell cytoplasm. The most affected group was that of the diabetics on month 12 (GDM2). The treated diabetics showed the least alterations on month 12 (GTM2). CONCLUSION: Diabetic rats develop degenerative alterations in the Bruch membrane and choroidal vessels. These alterations are more evident in animals submitted to chronic disease, but they are also present in acute disease. Degenerative processes were not avoided with short-term treatment. Long-term treatment inhibited the progress of these processes.

Macular microcirculation blood flow in patients with age related macular degeneration treated with photodynamic therapy and transpupillary thermotherapy.

PURPOSE: To assess the macular retinal and choroidal microcirculation blood flow in patients with exudative age related macular degeneration before and after photodynamic therapy (PDT) or transpupillary thermotherapy (TTT) with Doppler laser scanning (HRF--Heidelberg retinal flowmeter). MATERIAL AND METHODS: Thirty patients with exudative age-related macular degeneration were included in a prospective study. The diagnosis was established based on ophthalmic examination and fluorescein angiography results. In all cases the subfoveal choroidal neovascularization (CNV) was present. Control group consists of the fellow eyes with early stage of AMD (19 eyes) or with disciform scar (11 eyes). In 15 eyes with active CNV PDT was performed and in remaining 15--TTT. In all cases the macular blood flow was measured with Heidelberg retina flowmeter (HRF) before therapy and then 1 week, 4 weeks and 10-12 weeks after treatment. RESULTS: At the baseline examination in a group of eyes with active CNV the mean values of macular blood flow were significantly higher comparing to the fellow eyes and reached respectively: 678.6 +/- 125.0 AU and 298.4 +/- 79.2 AU (p=0.001). Four weeks after treatment all eyes showed the reduction of macular blood flow comparing to the baseline values (p=0.001). Ten to twelve weeks after laser therapy in all cases the increased macular blood flow was detected comparing to the previous examination (p=0.01). During the follow-up period the macular blood flow in the fellow eyes were significantly lower than in treated eyes. CONCLUSIONS: The measurement of macular blood flow using Doppler scanning laser (HRF--Heidelberg retinal flowmeter) may act as a non-invasive and useful diagnostic tool in assessment of CNV activity in patients with exudative age-related degeneration before and after PDT or TTT.