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Fluorescein Angiograms (fluorescein + angiogram)
Selected AbstractsFurther survey of Australian ophthalmologist's diabetic retinopathy management: did practice adhere to National Health and Medical Research Council guidelines?CLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 6 2010Joshua Yuen MPH Abstract Background:, To compare the self-reported management of diabetic retinopathy by Australian ophthalmologists with the 1997 National Health and Medical Research Council (NHMRC) guidelines. Methods:, Self-reported cross-sectional survey of patterns of practice. Questionnaires were sent to all Australian ophthalmologists, comprising questions regarding professional details, diabetic retinopathy screening attitudes/practices and specific hypothetical management scenarios. Data were analysed using Chi-squared and adjusted logistic regression. Result:, 480 of the 751 (64%) eligible Australian ophthalmologists participated. The majority (80%, n = 376) reported they consistently reviewed patient's glycaemic control, but only 55% and 41% regularly reviewed blood pressure and serum cholesterol control, respectively. Ophthalmologists generally adhered to NHMRC-recommended screening intervals, although only 38% agreed with the guidelines relating to screening of pre-pubertal diabetic patients. Fluorescein angiogram was used more than recommended, especially for mild non-proliferative diabetic retinopathy where 45% of respondents used this investigation. Practice duration >15 years was associated with more regular fluorescein angiogram use (OR = 3.74; 95% CI: 2.53,5.53, P < 0.001). In the clinical scenarios where clinically significant macular oedema was concurrently present with cataract or proliferative diabetic retinopathy, >26% referred to retinal subspecialists for management; 85% of the remaining ophthalmologists performed macular laser first. Respondents with practice duration >15 years were 7.8 times (P = 0.001) more likely to perform cataract surgery first. Conclusion:, Diabetic retinopathy management guidelines were generally well followed by Australian ophthalmologists. However, areas of practice variation existed including frequent use of fluorescein angiogram. Significant proportion of practitioners referred diabetic patients to retinal subspecialists, who were more likely to adhere to guideline recommendations. Ophthalmologists with greater experience (>15 years) were more likely to employ practices differing from NHMRC recommendations. [source] Analysis of mean retinal transit time from fluorescein angiography in human eyes: normal values and reproducibilityACTA OPHTHALMOLOGICA, Issue 6 2002G. Bjärnhall ABSTRACT. Objective:, To evaluate three different techniques to quantify retinal blood flow transit times in normal human eyes from fluorescein angiograms. Subjects and Methods:, Fluorescein angiograms were recorded on two different occasions in 18 normal individuals with a scanning laser ophthalmoscope. The angiograms were digitized (5 frames per second) and the images were aligned. Mean transit times (MTT) were analysed with a newly developed technique based on an impulse-response analysis (MTTIR) and again with the conventional technique (MTTSLOPE). Arterio-venous passage times (AVP) were also calculated. Results:, At the first determination, mean values (SD) for MTTIR, MTTSLOPE, and AVP were 3.22 (0.78), 4.88 (1.86), and 1.46 (0.57) seconds, respectively. Detection of an increase of 25% with a power of 80% requires groups of 12, 86 and 17 individuals for the three techniques, respectively. Conclusions:, Mean transit time is a well-defined physiological parameter. The technique based on impulse-response analysis allows for analysis of even badly defined dye curves. We found this technique to be superior to the conventional technique in terms of reproducibility. [source] Clinical and Histological Aspects of CNV Formation: Studies in an Animal ModelACTA OPHTHALMOLOGICA, Issue thesis2 2008Nathan Lassota MD Abstract. The purpose of the present thesis was to develop an animal model of CNV in order to study the early formation of CNV and to test the effects of an anti-angiogenic treatment. Porcine eyes were chosen as a substrate for CNV induction, since they are similar to human eyes in terms of both macroscopic and microscopic morphology. However, a major difference is that pigs lack a fovea; instead they have a visual streak, with a relatively stable and high concentration of cones. By surgical perforation of Bruch's membrane we were able to induce formation of CNV membranes. The morphology and cellular composition of these membranes varied with the surgical technique employed. When RPE cells were locally removed at the time of perforation, the resulting CNV was thinner, contained fewer blood vessels and was less prone to leak on fluorescein angiography than when RPE cells were left intact at induction. The neuroretina overlying the perforation site was not damaged by any of the surgical techniques, thus allowing the subsequent retinal damage to be ascribed to the actual process of CNV formation. Using this animal model allowed us to directly map histological findings onto fluorescein angiograms and thereby perform meaningful correlations between histopathologic and photographic features. Such correlations have been hampered in human subjects, since human eyes are not enucleated as a consequence of CNV and are therefore only available for post-mortem studies. In such studies there often is a considerable time-gap between the death of the patient and the latest available fluorescein angiogram, thereby allowing macular pathology to evolve in the interim. Histological examination of the porcine membranes demonstrated that they were composed of RPE cells, glial cells, macrophages, endothelial cells, collagen and smooth muscle fibres, which are the same cellular and fibrillar elements that dominate human CNV membranes. The porcine model was applied to test the effects, in a randomized and masked fashion, of intravitreally injected bevacizumab. Bevacizumab, a pan VEGF A antibody, was found to reduce both the proliferation of endothelial cells in CNV membranes and the propensity to leak in fluorescein angiograms. Immunohistochemically, bevacizumab was detected in the inner limiting membrane, in retinal blood vessels and binding uniformly to the entire CNV membrane without any cellular predisposition. Based on the above findings we believe that the porcine CNV model shows a bearing to human disease and therefore might be used as a tool to obtain improved treatments for this debilitating condition. [source] Further survey of Australian ophthalmologist's diabetic retinopathy management: did practice adhere to National Health and Medical Research Council guidelines?CLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 6 2010Joshua Yuen MPH Abstract Background:, To compare the self-reported management of diabetic retinopathy by Australian ophthalmologists with the 1997 National Health and Medical Research Council (NHMRC) guidelines. Methods:, Self-reported cross-sectional survey of patterns of practice. Questionnaires were sent to all Australian ophthalmologists, comprising questions regarding professional details, diabetic retinopathy screening attitudes/practices and specific hypothetical management scenarios. Data were analysed using Chi-squared and adjusted logistic regression. Result:, 480 of the 751 (64%) eligible Australian ophthalmologists participated. The majority (80%, n = 376) reported they consistently reviewed patient's glycaemic control, but only 55% and 41% regularly reviewed blood pressure and serum cholesterol control, respectively. Ophthalmologists generally adhered to NHMRC-recommended screening intervals, although only 38% agreed with the guidelines relating to screening of pre-pubertal diabetic patients. Fluorescein angiogram was used more than recommended, especially for mild non-proliferative diabetic retinopathy where 45% of respondents used this investigation. Practice duration >15 years was associated with more regular fluorescein angiogram use (OR = 3.74; 95% CI: 2.53,5.53, P < 0.001). In the clinical scenarios where clinically significant macular oedema was concurrently present with cataract or proliferative diabetic retinopathy, >26% referred to retinal subspecialists for management; 85% of the remaining ophthalmologists performed macular laser first. Respondents with practice duration >15 years were 7.8 times (P = 0.001) more likely to perform cataract surgery first. Conclusion:, Diabetic retinopathy management guidelines were generally well followed by Australian ophthalmologists. However, areas of practice variation existed including frequent use of fluorescein angiogram. Significant proportion of practitioners referred diabetic patients to retinal subspecialists, who were more likely to adhere to guideline recommendations. Ophthalmologists with greater experience (>15 years) were more likely to employ practices differing from NHMRC recommendations. [source] Visual outcomes following vitrectomy and peeling of epiretinal membraneCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 4 2005James G Wong MMed Abstract Background:, Visual outcomes of patients following vitrectomy and peeling of visually significant epiretinal membranes were assessed to determine the influence of specific perioperative factors and surgical complications on final visual acuity and functional vision. Methods:, In an unmatched, consecutive surgical series, vitrectomy and membrane peeling were performed on 125 eyes of 123 patients with visually significant macular epiretinal membranes. Patients were followed for 6,36 months. Visual outcome measures included postoperative logMAR visual acuity, change in visual acuity and functional vision tasks evaluated by questionnaire. Perioperative factors including duration of symptoms, preoperative visual acuity, aetiology, membrane type and leakage on fundal fluorescein angiogram were correlated with final visual outcomes. Results:, Visual acuity improved by a mean of 0.31 ± 0.21 units (three lines of vision). In 104 cases (83%), visual acuity improved in patients by two lines or more, with 20 cases (16%) having unchanged acuity and one case (1%) having worse acuity. Ninety-three per cent of interviewed cases reported improvement in functional vision, especially reduction of distortion. Cataract was observed in 52 cases (52% of phakic eyes) postoperatively compared with 19 cases (19%) preoperatively. Postoperative visual acuity correlated with preoperative visual acuity. Patients with worse preoperative vision recorded greater visual improvement following surgery. No other perioperative factors were found to have a prognostic value in this study. Conclusion:, Epiretinal membrane peeling improves vision in the majority of patients with significant symptoms, even if preoperative visual acuity is not substantially reduced. Surgery improves functional vision including metamorphopsia not measurable by visual acuity, and thus assessment of functional vision should be included in surgical case planning. [source] Clinical and histological findings after intravitreal injection of bevacizumab (Avastin®) in a porcine model of choroidal neovascularizationACTA OPHTHALMOLOGICA, Issue 3 2010Nathan Lassota Abstract. Purpose:, To examine the effect of intravitreally injected bevacizumab (Avastin®) on the histological and angiographic morphology of choroidal neovascularization (CNV) in a masked and placebo-controlled animal study. Methods:, Choroidal neovascularization was induced surgically in 11 porcine eyes by perforating Bruch's membrane with a retinal perforator. After closure of the ports used for the vitrectomy, which was performed to facilitate the Bruch's membrane rupture, 0.05 ml of either bevacizumab or Ringer-Lactat (placebo) was injected into the vitreous cavity. Eyes were enucleated after 14 days. Fundus photographs and fluorescein angiograms (FAs) were obtained immediately prior to enucleation. Sections of formalin- and paraffin-embedded eyes were examined by light microscopy and by immunohistochemical staining. Results:, Placebo-injected eyes exhibited the highest propensity to leak, with five of six eyes leaking on FA, whereas only one of five bevacizumab-injected eyes exhibited leakage. On histological examination, all 11 eyes contained CNV membranes of similar size, regardless of treatment. The number of vascular endothelial cells was significantly reduced (p = 0.03) in CNV membranes from eyes that had been injected with bevacizumab when compared with CNV membranes from placebo-injected eyes. There was a trend towards more retinal pigment epithelium cells (p = 0.16) and fewer glial fibres (p = 0.08) in membranes from bevacizumab-treated eyes compared with placebo-treated eyes. Bevacizumab was identified immunohistochemically in the inner limiting membrane (ILM) and to a lesser degree in the remaining retina. Strong staining was also detected in both retinal blood vessels and entire CNV membranes with no cellular predisposition. Vascular endothelial growth factor expression was found in the CNV membranes, in the ILM, in the ganglion cell layer, in Müller cells throughout the neuroretina and in retinal blood vessels. Conclusions:, Bevacizumab significantly reduced the proliferation of vascular endothelial cells in CNV membranes and showed a strong trend towards a reduction of leakage from these membranes. After a single injection, bevacizumab did not exhibit a size reducing effect on CNV, but it was still present in the membranes 14 days after intravitreal injection. [source] Global angiographic scoring system for inflammatory diseasesACTA OPHTHALMOLOGICA, Issue 2009M KHAIRALLAH Purpose Fundus fluorescein and indocyanine green angiography are essential imaging techniques in the appraisal of posterior segment inflammation. A combined fluorescein and indocyanine green angiographic scoring system has been developed in order to provide semi-quantitative data for follow-up of disease progression, monitoring response to treatment, and comparison between clinical studies. We tested interobserver variations in the semi-quantitative scoring of dual fluorescein/indocyanine green angiograms. Methods Four observers scored 32 dual fluorescein and indocyanine green angiograms. Spearman rank correlation was used to analyze correlation between scores assigned to each angiographic sign. We used the Kappa statistics to test agreement between pairs of observers in comparative total fluorescein and indocyanine green angiographic scores. Results We found a significant correlation between pairs of observers in scores assigned to each fluorescein angiographic sign and the total score of fluorescein angiograms. A significant correlation was found only between 2 separate pairs of observers in scores assigned to early stromal vessel hyperfluoresence on indocyanine green angiography. However, a significant correlation was found in other indocyanine green angiographic signs and the total score of indocyanine green angiograms. There was a good agreement between observers in comparative fluorescein , indocyanine green angiographic total scores. Conclusion Further experience with the scoring system, especially with the indocyanine green angiographic scoring, may improve its reproducibility. [source] Clinical and Histological Aspects of CNV Formation: Studies in an Animal ModelACTA OPHTHALMOLOGICA, Issue thesis2 2008Nathan Lassota MD Abstract. The purpose of the present thesis was to develop an animal model of CNV in order to study the early formation of CNV and to test the effects of an anti-angiogenic treatment. Porcine eyes were chosen as a substrate for CNV induction, since they are similar to human eyes in terms of both macroscopic and microscopic morphology. However, a major difference is that pigs lack a fovea; instead they have a visual streak, with a relatively stable and high concentration of cones. By surgical perforation of Bruch's membrane we were able to induce formation of CNV membranes. The morphology and cellular composition of these membranes varied with the surgical technique employed. When RPE cells were locally removed at the time of perforation, the resulting CNV was thinner, contained fewer blood vessels and was less prone to leak on fluorescein angiography than when RPE cells were left intact at induction. The neuroretina overlying the perforation site was not damaged by any of the surgical techniques, thus allowing the subsequent retinal damage to be ascribed to the actual process of CNV formation. Using this animal model allowed us to directly map histological findings onto fluorescein angiograms and thereby perform meaningful correlations between histopathologic and photographic features. Such correlations have been hampered in human subjects, since human eyes are not enucleated as a consequence of CNV and are therefore only available for post-mortem studies. In such studies there often is a considerable time-gap between the death of the patient and the latest available fluorescein angiogram, thereby allowing macular pathology to evolve in the interim. Histological examination of the porcine membranes demonstrated that they were composed of RPE cells, glial cells, macrophages, endothelial cells, collagen and smooth muscle fibres, which are the same cellular and fibrillar elements that dominate human CNV membranes. The porcine model was applied to test the effects, in a randomized and masked fashion, of intravitreally injected bevacizumab. Bevacizumab, a pan VEGF A antibody, was found to reduce both the proliferation of endothelial cells in CNV membranes and the propensity to leak in fluorescein angiograms. Immunohistochemically, bevacizumab was detected in the inner limiting membrane, in retinal blood vessels and binding uniformly to the entire CNV membrane without any cellular predisposition. Based on the above findings we believe that the porcine CNV model shows a bearing to human disease and therefore might be used as a tool to obtain improved treatments for this debilitating condition. [source] Analysis of mean retinal transit time from fluorescein angiography in human eyes: normal values and reproducibilityACTA OPHTHALMOLOGICA, Issue 6 2002G. Bjärnhall ABSTRACT. Objective:, To evaluate three different techniques to quantify retinal blood flow transit times in normal human eyes from fluorescein angiograms. Subjects and Methods:, Fluorescein angiograms were recorded on two different occasions in 18 normal individuals with a scanning laser ophthalmoscope. The angiograms were digitized (5 frames per second) and the images were aligned. Mean transit times (MTT) were analysed with a newly developed technique based on an impulse-response analysis (MTTIR) and again with the conventional technique (MTTSLOPE). Arterio-venous passage times (AVP) were also calculated. Results:, At the first determination, mean values (SD) for MTTIR, MTTSLOPE, and AVP were 3.22 (0.78), 4.88 (1.86), and 1.46 (0.57) seconds, respectively. Detection of an increase of 25% with a power of 80% requires groups of 12, 86 and 17 individuals for the three techniques, respectively. Conclusions:, Mean transit time is a well-defined physiological parameter. The technique based on impulse-response analysis allows for analysis of even badly defined dye curves. We found this technique to be superior to the conventional technique in terms of reproducibility. [source] Retinal manifestations of ophthalmic artery hypoperfusionCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 4 2002Terrence J Ong MBBS Abstract Ophthalmic artery hypoperfusion is a relatively uncommon clinical entity. This study illustrates the posterior segment findings of ophthalmic artery hypoperfusion in a series of nine patients. Colour photographs and relevant fluorescein angiograms highlighting the findings are shown. The retinal manifestations of ophthalmic artery hypoperfusion in this series of patients include midperipheral haemorrhages, dilated retinal veins, optic disk collaterals, optic disk neovascularization, cotton wool spots, grey intraretinal lesions, fundus pallor, optic disk swelling and choroidal infarcts. Recognition of the ophthalmic changes in this condition may lead to detection of carotid artery disease, the surgical and medical treatment of which has important bearing on patient management. [source] | ||||||||||