Short-term changes in Bruch's membrane opening-based morphometrics during the first week after trabeculectomy.

PURPOSE: To evaluate the dynamics of Bruch's membrane opening-based morphometrics of the optic nerve head (ONH) using spectral-domain optical coherence tomography (SD-OCT) during the first week after glaucoma surgery by trabeculectomy with mitomycin C. METHODS: Prospective, longitudinal analysis of 25 eyes of 25 patients treated by trabeculectomy. Twenty-four eyes had evaluable postoperative SD-OCT examinations. Bruch's membrane opening minimum rim width (BMO-MRW) and peripapillary retinal nerve fiber layer (RNFL) thickness were analyzed at baseline before surgery, 1 day, 2 to 3 days, and 1 week after surgery. Changes compared to baseline were correlated to intraocular pressure (IOP). RESULTS: One day after surgery, the mean BMO-MRW changed by + 26.17 µm, p = 0.001 (mean IOP reduction by 17.01 mmHg). This increase persisted on day 2-3 with a mean increase of BMO-MRW of + 25.33 µm, p = 0.001 (mean IOP reduction by 20.46 mmHg) and by week 1 with a mean BMO-MRW increase of + 33.17 µm, p < 0.001 (mean IOP reduction by 22.55 mmHg). The increase in BMO-MRW correlated significantly with the reduction of IOP on day 1 (Spearman's rho ρ = 0.656, p = 0.003) and d2-3 (Spearman's rho ρ = 0.479, p = 0.038). There was no statistically significant correlation found between the IOP and the increase in BMO-MRW in week 1. RNFL thickness showed no significant changes at day 1 as well as days 2-3 (p ≥ 0.078, respectively). It showed a small but significant increase in week 1 by 3.94 µm, p = 0.015. CONCLUSIONS: Structural reversal of disc cupping in BMO-MRW occurs as early as 1 day after trabeculectomy and correlates to the extent of the IOP reduction. During the whole first week after surgery, a strong increase in BMO-MRW can be noted. The changes in BMO-based parameters need to be considered when evaluating patients' longitudinal follow-up.

Determinants of lamina cribrosa depth in healthy Asian eyes: the Singapore Epidemiology Eye Study.

AIM: To investigate the determinants of lamina cribrosa depth (LCD) in healthy eyes of Chinese and Indian Singaporean adults. METHODS: The optic nerve head (ONH) of the right eye of 1396 subjects (628 Chinese and 768 Indian subjects) was imaged with optical coherence tomography (OCT, Spectralis, Heidelberg, Germany). LCD was defined as the distance from the Bruch's membrane opening (LCD-BMO) or the peripapillary sclera (LCD-PPS) reference plane to the laminar surface. A linear regression model was used to evaluate the relationship between the LCD and its determinants. RESULTS: Both LCDs were significantly different between the two races (LCD-BMO: 421.95 (95% CI 365.32 to 491.79) µm in Chinese vs 430.39 (367.46-509.81) µm in Indians, p=0.021; and LCD-PPS: 353.34 (300.98-421.45) µm in Chinese vs 376.76 (313.39-459.78) µm in Indians, p<0.001). In the multivariable regression analysis, the LCD-PPS of the whole cohort was independently associated with females (ß=-31.93, p<0.001), Indians subjects (ß=21.39, p=0.004) (Chinese as the reference), axial length (Axl) (ß=-6.68, p=0.032), retinal nerve fibre layer thickness (RNFL) (ß=0.71, p=0.019), choroidal thickness (ChT) (ß=0.41, p<0.001), vertical cup disc ratio (VCDR) (ß=24.42, p<0.001) and disc size (ß=-60.75, p=0.001). For every 1 year older in age, the LCD-PPS was deeper on average by 1.95 µm in Chinese subjects (p=0.01) but there was no association in Indians subjects (p=0.851). CONCLUSIONS: The LCD was influenced by age, gender, race, Axl, RNFL, ChT, VCDR and disc size. This normative LCD database may facilitate a more accurate assessment of ONH cupping using OCT in Asian populations.

Bruch's Membrane Opening Minimum Rim Width Provides Objective Differentiation between Glaucoma and Nonglaucomatous Optic Neuropathies.

PURPOSE: A challenging clinical scenario is distinguishing between normal tension glaucoma (NTG) and non-glaucomatous optic neuropathies (NGON). The key to the assessment remains identifying the presence of optic nerve head cupping. Recent optical coherence tomography (OCT) measurements now allow objective assessment of cupping by minimum rim width at Bruch's membrane opening (MRW-BMO). This study assessed the hypothesis that the MRW-BMO measurement quantifies cupping and therefore can differentiate between NTG and NGON. DESIGN: Diagnostic evaluation with area under the curve. METHODS: Setting: multicenter tertiary hospitals and outpatient clinics. PATIENT POPULATION: 81 eyes of 81 patients were enrolled, 27 with NTG and 54 with NGON, including ischemic optic neuropathy, previous optic neuritis, and compressive and inherited optic neuropathies. All NGON patients with intraocular pressure >21 mm Hg, narrow drainage angles, or a family history of glaucoma were excluded. Observational procedure: optic disc OCT images were obtained of both the retinal nerve fiber layer thickness and the MRW-BMO. MAIN OUTCOME MEASUREMENTS: the utility of the MRW-BMO in differentiating GON from NGON was assessed using the area under the curve (AUC) estimated from a logistic regression model. RESULTS: The 5-fold cross-validated AUC for glaucoma versus nonglaucoma from logistic regression models using MRW-BMO values from all sectors was 0.95 (95% confidence interval: 0.86-1.00). CONCLUSIONS: The measurement of MRW-BMO effectively differentiates between NTG and NGON with a high level of sensitivity and specificity. Incorporating this measurement into routine glaucoma assessment may provide a robust method of assisting clinicians to improve diagnosis and therefore treatment of optic nerve diseases.

Dynamics of structural reversal in Bruch's membrane opening-based morphometrics after glaucoma drainage device surgery.

PURPOSE: Structural reversal of disc cupping is a known phenomenon after trabeculectomy. The aim of this retrospective, longitudinal, cross-sectional analysis was to evaluate the postoperative dynamics of Bruch's membrane opening-based morphometrics of the optic nerve head following glaucoma drainage device surgery. METHODS: Forty-three eyes, treated by glaucoma drainage device surgery, were included in the study. Individual changes in the spectral domain optic coherence tomography (SD-OCT) parameters Bruch's membrane opening minimum rim width (BMO-MRW), Bruch's membrane opening minimum rim area (BMO-MRA) and peripapillary retinal nerve fiber layer (RNFL) thickness as well as mean defect in 30-2 perimetry were analyzed. Changes were correlated to postoperative intraocular pressure levels over time. Available follow-up visits were aggregated and grouped into a short-term follow-up (20 to 180 days after surgery), a midterm follow-up (181 to 360 days after surgery) and a long-term follow-up (more than 360 days after surgery). RESULTS: In short-term follow-up, BMO-MRW and BMO-MRA increased significantly (p <= 0.034). This increase correlated negatively with the intraocular pressure at the time of the follow-up (Pearson's rho = - 0.49; p = 0.039). From 6 months after surgery on, there was no statistically significant change in BMO-MRW and BMO-MRA (p >= 0.207). RNFL thickness and mean defect of 30-2 perimetry showed no significant changes after GDD implantation (p >= 0.189). CONCLUSIONS: Lowering of intraocular pressure by glaucoma drainage device surgery leads to an increase of Bruch's membrane opening based parameters in the first 6 months after surgery. These changes have to be taken into account when evaluating patients' longitudinal follow-up after glaucoma drainage device implantation.

Interactions of the choroid, Bruch's membrane, retinal pigment epithelium, and neurosensory retina collaborate to form the outer blood-retinal-barrier.

The three interacting components of the outer blood-retinal barrier are the retinal pigment epithelium (RPE), choriocapillaris, and Bruch's membrane, the extracellular matrix that lies between them. Although previously reviewed independently, this review integrates these components into a more wholistic view of the barrier and discusses reconstitution models to explore the interactions among them. After updating our understanding of each component's contribution to barrier function, we discuss recent efforts to examine how the components interact. Recent studies demonstrate that claudin-19 regulates multiple aspects of RPE's barrier function and identifies a barrier function whereby mutations of claudin-19 affect retinal development. Co-culture approaches to reconstitute components of the outer blood-retinal barrier are beginning to reveal two-way interactions between the RPE and choriocapillaris. These interactions affect barrier function and the composition of the intervening Bruch's membrane. Normal or disease models of Bruch's membrane, reconstituted with healthy or diseased RPE, demonstrate adverse effects of diseased matrix on RPE metabolism. A stumbling block for reconstitution studies is the substrates typically used to culture cells are inadequate substitutes for Bruch's membrane. Together with human stem cells, the alternative substrates that have been designed offer an opportunity to engineer second-generation culture models of the outer blood-retinal barrier.

IMPAIRED DARK ADAPTATION ASSOCIATED WITH A DISEASED BRUCH MEMBRANE IN PSEUDOXANTHOMA ELASTICUM.

PURPOSE: To characterize dark adaptation in patients with pseudoxanthoma elasticum, a systemic disease leading to calcification of elastic tissue including the Bruch membrane. METHODS: In this prospective case-control study, dark adaptation thresholds were measured using a Goldmann-Weekers dark adaptometer. Additional assessments included best-corrected visual acuity testing, contrast sensitivity, low luminance deficit, and vision-related quality of life. RESULTS: Dark adaptation thresholds were significantly higher, and adaptation periods were prolonged in patients with pseudoxanthoma elasticum (n = 35; 33 with 2 ABCC6 mutations) compared with controls (n = 35). The time to adapt 4 log units (20.6 ± 8.6 vs. 8.0 ± 1.3 minutes) and the mean dark adaptation threshold after 15 minutes (3.5 ± 1.1 vs. 1.8 ± 0.2 log units) were significantly different between patients and controls (both P < 0.001). Low luminance deficits (12.3 ± 6.4 vs. 6.1 ± 4.3 ETDRS letters), contrast sensitivity (1.4 ± 0.3 vs. 1.9 ± 0.1), and low luminance-related quality of life (LLQ score: 1,286 ± 355 vs. 2,167 ± 68) were also significantly worse in patients with pseudoxanthoma elasticum (all, P < 0.001). Two patients were treated with high-dose vitamin A which partially reversed impaired dark adaptation. CONCLUSION: Patients with pseudoxanthoma elasticum often have impaired dark adaptation. Positive effects of vitamin A supplementation may indicate restricted retinal access of vitamin A through the Bruch membrane as one possible underlying pathogenic factor.

On the origin of proteins in human drusen: The meet, greet and stick hypothesis.

Retinal drusen formation is not only a clinical hallmark for the development of age-related macular degeneration (AMD) but also for other disorders, such as Alzheimer's disease and renal diseases. The initiation and growth of drusen is poorly understood. Attention has focused on lipids and minerals, but relatively little is known about the origin of drusen-associated proteins and how they are retained in the space between the basal lamina of the retinal pigment epithelium and the inner collagenous layer space (sub-RPE-BL space). While some authors suggested that drusen proteins are mainly derived from cellular debris from processed photoreceptor outer segments and the RPE, others suggest a choroidal cell or blood origin. Here, we reviewed and supplemented the existing literature on the molecular composition of the retina/choroid complex, to gain a more complete understanding of the sources of proteins in drusen. These "drusenomics" studies showed that a considerable proportion of currently identified drusen proteins is uniquely originating from the blood. A smaller, but still large fraction of drusen proteins comes from both blood and/or RPE. Only a small proportion of drusen proteins is uniquely derived from the photoreceptors or choroid. We next evaluated how drusen components may "meet, greet and stick" to each other and/or to structures like hydroxyapatite spherules to form macroscopic deposits in the sub-RPE-BL space. Finally, we discuss implications of our findings with respect to the previously proposed homology between drusenogenesis in AMD and plaque formation in atherosclerosis.

Impact of ab-interno trabeculectomy on Bruch's membrane opening-based morphometry of the optic nerve head for glaucoma progression analysis.

PURPOSE: To analyze the longitudinal change in Bruch's membrane opening minimal rim width (BMO-MRW) and circumpapillary retinal nerve fiber layer (RNFL) thickness using spectral domain optical coherence tomography (SD-OCT) after glaucoma surgery via ab-interno trabeculectomy in adult glaucoma patients. METHODS: Retrospective audit of 65 eyes of 65 participants undergoing ab-interno trabeculectomy using electroablation of the trabecular meshwork. In 53 eyes, surgery was combined with phacoemulsification and posterior chamber lens implantation. Pre- and postoperative SD-OCT examinations of the optic nerve head (ONH), intraocular pressure (IOP), and visual field data were analyzed. Longitudinal change in morphometric SD-OCT parameters of the ONH was compared and correlated to change in IOP and visual field function. RESULTS: BMO-MRW increased significantly between baseline (BL) and follow-up (FU) within the first 6 months after surgery (BL = 167.85 ± 90 µm; FU = 175.59 ± 89 µm; p = 0.034). This increase correlated with postoperative lowering of IOP (rho = - 0.41; p = 0.016). Nine months after surgery (range, 7-12 months), there was no significant change in BMO-MRW (BL = 196.79 ± 79; FU = 196.47 ± 85 µm; p = 0.95), while in later follow-up, a decrease of BMO-MRW was found (BL = 175.18 ± 78; FU = 168.65 ± 72; p = 0.05). RNFL thickness was unchanged in early (p > 0.16) and significantly decreased in later follow-up (p = 0.009). Mean deviation (MD) of visual field function did not show a significant change before and after surgery. CONCLUSION: Electroablative ab-interno trabeculectomy leads to a significant transient mild increase in BMO-MRW. This increase was shown to correlate with IOP lowering. Significant loss of BMO-MRW in later follow-up may reflect insufficient IOP reduction by surgery. The parameters RNFL thickness and MD seem less impacted directly by surgery.

Structural Reversal of Disc Cupping After Trabeculectomy Alters Bruch Membrane Opening-Based Parameters to Assess Neuroretinal Rim.

OBJECTIVE: To assess the impact of trabeculectomy for glaucoma on morphometric neuroretinal parameters of the optic nerve head (ONH) using spectral-domain optical coherence tomography (SD-OCT). DESIGN: Retrospective, interventional case series. METHODS: Participants: Eighty-eight eyes of 88 patients who underwent trabeculectomy with mitomycin C in 2016. INTERVENTION: All patients underwent trabeculectomy in 1 eye (study eye) and had evaluable SD-OCT examinations of the ONH to measure neuroretinal tissue before and at least at 1 of the 3-, 6-, and 12-month follow-up time points after surgery. MAIN OUTCOME MEASURES: Longitudinal change in Bruch membrane opening minimum rim width (BMO-MRW), Bruch membrane opening minimum rim area (BMO-MRA), peripapillary retinal nerve fiber layer (RNFL) thickness, intraocular pressure (IOP), and mean deviation in perimetry. RESULTS: In study eyes, BMO-MRW significantly increased postsurgically comparing baseline and follow-up examinations at 3 months (P = .012), at 6 months (P = .007), and at 1 year (P = .010) after trabeculectomy. The increase in BMO-MRW 6 months after surgery correlated with IOP reduction (r = 0.48; P = .001). BMO-MRA showed an equal increase (P ≤ .034). RNFL thickness remained stable between baseline and follow-up at 3, 6, and 12 months and showed a moderate loss after 18 months (P = .021) of follow-up. CONCLUSIONS: Structural reversal of disc cupping after trabeculectomy markedly influences Bruch membrane opening-based parameters for up to more than 1 year. Improvement in morphometry seems to correlate with the reduction of IOP while visual field function appears not to be influenced. In longitudinal follow-up of glaucoma patients by SD-OCT, evaluation of BMO-based parameters necessitates to reflect bias caused by surgery.

Optimization of an Image-Guided Laser-Induced Choroidal Neovascularization Model in Mice.

The mouse model of laser-induced choroidal neovascularization (CNV) has been used in studies of the exudative form of age-related macular degeneration using both the conventional slit lamp and a new image-guided laser system. A standardized protocol is needed for consistent results using this model, which has been lacking. We optimized details of laser-induced CNV using the image-guided laser photocoagulation system. Four lesions with similar size were consistently applied per eye at approximately double the disc diameter away from the optic nerve, using different laser power levels, and mice of various ages and genders. After 7 days, the mice were sacrificed and retinal pigment epithelium/choroid/sclera was flat-mounted, stained with Isolectin B4, and imaged. Quantification of the area of the laser-induced lesions was performed using an established and constant threshold. Exclusion criteria are described that were necessary for reliable data analysis of the laser-induced CNV lesions. The CNV lesion area was proportional to the laser power levels. Mice at 12-16 weeks of age developed more severe CNV than those at 6-8 weeks of age, and the gender difference was only significant in mice at 12-16 weeks of age, but not in those at 6-8 weeks of age. Dietary intake of omega-3 long-chain polyunsaturated fatty acid reduced laser-induced CNV in mice. Taken together, laser-induced CNV lesions can be easily and consistently applied using the image-guided laser platform. Mice at 6-8 weeks of age are ideal for the laser-induced CNV model.

Modulating the Transport Characteristics of Bruch's Membrane With Steroidal Glycosides and its Relevance to Age-Related Macular Degeneration (AMD).

PURPOSE: Beneficial expectations of supplement therapies to increase the transport of nutrients, vitamins, and antioxidants across Bruch's membrane in AMD, by mass action alone, remain inconclusive. Therefore, the potential for targeting the transport pathways themselves to improve bidirectional exchange using amphipathic steroidal glycosides (ginsenosides) has been investigated. METHODS: Bruch's choroid preparations were mounted in modified Ussing chambers and basal levels of hydraulic conductivity (23 donors, age range, 12-89 years) and diffusional transport of FITC-albumin (21 donors, age range, 12-92 years) quantified. Then, following a 24-hour incubation with ginsenoside preparations, the transport parameters were re-evaluated and the resulting data analyzed with respect to aging and modulation by ginsenosides. RESULTS: Basal hydraulic conductivity of Bruch's showed an age-related exponential decline with a half-life of 19 years. Incubation with ginsenosides improved hydraulic conductivity with levels equivalent to donors 19 years younger. Across the age range examined, hydraulic conductivities were increased to 2.05-fold ± 0.38 (P < 0.001) of basal values. Diffusional transport of albumin across Bruch's also showed an age-related exponential decline with a half-life of 18 years. The decay curves were elevated on incubation with ginsenosides and diffusional rates were equivalent to donors 15 years younger. Diffusional rates were elevated 2.01-fold ± 0.49 over basal values (P < 0.001). CONCLUSIONS: Transport characteristics of human Bruch's can be improved by ginsenosides, facilitating the bidirectional exchange of nutrients and waste products across the membrane. With improved transport pathways, the need for supplement therapies becomes redundant. Slowed aging of Bruch's is expected to delay the onset and/or progression of AMD.

Effect of lutein and antioxidant supplementation on VEGF expression, MMP-2 activity, and ultrastructural alterations in apolipoprotein E-deficient mouse.

Oxidative stress is involved in the pathogenesis of several diseases such as atherosclerosis and age-related macular degeneration (AMD). ApoE-deficient mice (apoE(-/-)) are a well-established model of genetic hypercholesterolemia and develop retinal alterations similar to those found in humans with AMD. Thus supplementation with lutein or multivitamin plus lutein and glutathione complex (MV) could prevent the onset of these alterations. ApoE(-/-) mice (n = 40, 3 months old) were treated daily for 3 months with lutein (AE-LUT) or MV (two doses): AE-MV15 (15 mg/kg/day) and AE-MV50 (50 mg/kg/day) and were compared to controls with vehicle (AE-C). Wild-type mice (n = 10) were also used as control (WT-C). ApoE(-/-) mice showed higher retinal lipid peroxidation and increased VEGF expression and MMP-2 activity, associated with ultrastructural alterations such as basal laminar deposits, vacuoles, and an increase in Bruch's membrane thickness. While lutein alone partially prevented the alterations observed in apoE(-/-) mice, MV treatment substantially reduced VEGF levels and MMP-2 activity and ameliorated the retinal morphological alterations. These results suggest that oxidative stress in addition to an increased expression and activity of proangiogenic factors could participate in the onset or development of retinal alterations of apoE(-/-) mice. Moreover, these changes could be prevented by efficient antioxidant treatments.

Tumor-related lipid exudation after plaque radiotherapy of choroidal melanoma: the role of Bruch's membrane rupture.

PURPOSE: To identify the risk factors predictive of development of tumor-related lipid exudation (TRLE) after plaque radiotherapy of posterior uveal melanoma. DESIGN: Case-control study. PARTICIPANTS: Cases included 294 patients with posterior uveal melanoma who had developed TRLE after plaque radiotherapy. Controls included 294 patients with posterior uveal melanoma who had not developed TRLE after plaque radiotherapy. Controls were matched with cases for age, gender, and initial tumor thickness. METHODS: Data were extracted from medical charts containing demographic, clinical, and treatment information. Detailed fundus drawings and color fundus photographs were reviewed for each patient. MAIN OUTCOME MEASURES: Tumor and ocular features of eyes with posterior uveal melanoma treated with plaque radiotherapy. RESULTS: Multivariate analysis identified Bruch's membrane rupture (P<0.001), serous retinal detachment (RD) before radiation (P< or =0.019), closer proximity to the optic disc and foveola (P = 0.004 and 0.013, respectively), greater tumor base (P = 0.035), failure to receive transpupillary thermotherapy (TTT) after radiation (P<0.001), and initial increase of serous RD after radiation (P<0.001) as significant risk factors predictive of development of TRLE after plaque radiotherapy of posterior uveal melanoma. Radiation dose at the tumor base correlated with maximum extent of TRLE (P = 0.003). The mean interval between plaque radiotherapy and onset of TRLE was 14 months (median, 11 months; range, 2-97 months), with 88% of cases developing TRLE within 2 years of radiation. The interval between the onset of TRLE and the first evidence of its regression was a mean of 33 months (median, 38 months; range, 2-194 months). CONCLUSIONS: Our study identified Bruch's membrane rupture as an important factor predisposing to development of TRLE after plaque radiotherapy of posterior uveal melanoma. Other predictive factors included serous RD before radiation, large tumor basal diameter, posterior tumor location, lack of adjunctive TTT, and early increase of serous RD after plaque radiotherapy.

Effect of zeaxanthin and antioxidant supplementation on vascular endothelial growth factor (VEGF) expression in apolipoprotein-E deficient mice.

PURPOSE: Apolipoprotein E(-/-) deficient (apoE(-/-)) mice develop hypercholesterolemia, atherosclerosis, and retinal alterations. We studied the oxidative status and vascular endothelial growth factor (VEGF) expression in murine retinal pigment epithelium-choroid (RPE) and Bruch's membrane (BM) ultrastructure and the effect of zeaxanthin. METHODS: Ten 6-month-old C57BL/6 and 40 apoE(-/-) mice were divided into four groups (n = 10 each) and fed different diets for 12 weeks based on body weight: wild type (WT) and apoE(-/-) (AE-Con) mice standard rodent chow; apoE(-/-) mice (AES) standard rodent chow with ascorbate (800 mg/kg), tocopherol (1053 mg/kg), and zinc (135 mg/kg); and apoE(-/-) mice the last diet plus zeaxanthin with either 0.4 g/kg (AES-Z04) or 4 g/kg feed (AES-Z4). RESULTS: Plasma total cholesterol (TC) and triglycerides (TG) and urine lipid peroxidation (isoprostanes) were measured. VEGF expression was determined in RPE-choroid homogenates. Zeaxanthin uptake was assessed in liver and retina by high-performance liquid chromatography; the retinal ultrastructure was analyzed by electron microscopy. AE-Con mice had higher plasma TC (p < 0.001) and TG (p < 0.001) values than WT mice. AE-Con mice had higher RPE-choroid-VEGF levels than WT mice (p < 0.05), BM thickness (p < 0.001) and presence of basal laminar deposits (BLamD). AES-Z4 resulted in lower urinary isoprostanes (p = 0.054) and lower VEGF expression in the RPE-choroid (p < 0.01). BM in the AES-Z4 animals had less confluent BLamD than AE-Con, AES, or AES-Z04 animals. CONCLUSIONS: We have reported that supplementation with zeaxanthin and antioxidants may delay or reverse alterations in the RPE and deposits in BM, and reduced VEGF expression observed in apoE(-/-) mice.

Lipoprotein particles of intraocular origin in human Bruch membrane: an unusual lipid profile.

PURPOSE: Throughout adulthood, Bruch membrane (BrM) accumulates esterified cholesterol (EC) associated with abundant 60- to 80-nm-diameter lipoprotein-like particles (LLP), putative apolipoprotein B (apoB) lipoproteins secreted by the retinal pigment epithelium (RPE). In the present study, neutral lipid, phospholipids, and retinoid components of human BrM-LLP were assayed. METHODS: Particles isolated from paired choroids of human donors were subjected to comprehensive lipid profiling (preparative liquid chromatography [LC] gas chromatography [GC]), thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), Western blot analysis, and negative stain electron microscopy. Results were compared to plasma lipoproteins isolated from normolipemic volunteers and to conditioned medium from RPE-J cells supplemented with palmitate to induce particle synthesis and secretion. RESULTS: EC was the largest component (32.4+/-7.9 mol%) of BrM-LLP lipids. EC was 11.3-fold more abundant than triglyceride (TG), unlike large apoB lipoproteins in plasma. Of the fatty acids (FA) esterified to cholesterol, linoleate (18:2n6) was the most abundant (41.7+/-4.7 mol%). Retinyl ester (RE) was detectable at picomolar levels in BrM-LLP. Notably scarce in any BrM-LLP lipid class was the photoreceptor-abundant FA docosahexaenoate (DHA, 22:6n3). RPE-J cells synthesized apoB and numerous EC-rich spherical particles. CONCLUSIONS: BrM-LLP composition resembles plasma LDL more than it does photoreceptors. An EC-rich core is possible for newly synthesized lipoproteins as well as those processed in plasma. Abundant EC could contribute to a transport barrier in aging and lesion formation in age-related maculopathy (ARM). Analysis of BrM-LLP composition has revealed new aspects of retinal cholesterol and retinoid homeostasis.

[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.

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

OBJETIVO: Conhecer os efeitos do diabetes e o impacto de seu tratamento medicamentoso em curto e longo prazo sobre os vasos da coróide e membrana de Bruch. MÉTODOS: Foram estudados 30 ratos Wistar, divididos em 3 grupos experimentais: grupo controle (GC), grupo diabético (GD) e grupo diabético tratado (GT), estudados 1 mês (momento M1) e 12 meses (momento M2) após o início do experimento. O diabetes foi induzido por aloxana endovenosa, na dose de 42 mg/kg. O GT foi tratado com hipoglicemiante oral (acarbose) e insulina subcutânea. Após o sacrifício, os olhos foram preparados para exame ao microscópio eletrônico de transmissão, interessando a ultra-estrutura da membrana de Bruch e os vasos da coróide. RESULTADOS: O exame ultra-estrutural da coróide dos ratos diabéticos mostrou depósitos na membrana de Bruch, acúmulo de vesículas, glicogênio e corpos densos no citoplasma das células endoteliais. O grupo mais afetado foi de ratos diabéticos de 12 meses (GDM2). Os animais com menor intensidade de alterações foram os ratos tratados por 12 meses (GTM2). CONCLUSÃO: Os ratos diabéticos desenvolveram alterações degenerativas na membrana de Bruch e vasos da coróide. Estas alterações foram mais evidentes nos animais submetidos à doença crônica, mas também ocorreram agudamente. O tratamento a curto prazo não foi capaz de evitar os processos degenerativos. A longo prazo, o tratamento inibiu a progressão destes processos.

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 coroid 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.

[Primary intraocular lymphoma with unusual clinical presentation and poor outcome]. / Primäres intraokuläres Lymphom mit untypischer Klinik und ungünstigem Verlauf.

BACKGROUND: Primary intraocular lymphoma is a distinct subset of primary non-Hodgkin's lymphoma of the CNS. In general, the primary non-Hodgkin's lymphoma of the CNS is rare, accounting for 1 % of all non-Hodgkin's lymphomas and less than 1 % of all intraocular tumors. HISTORY AND SIGNS: A 70-year-old man was hospitalized in June 2002 because of acute loss of vision on his left eye. A severe vitreous hemorrhage was observed. Ultrasound showed solid subretinal lesions at the posterior fundus. Diagnostic vitreous surgery including a biopsy was performed. An intraocular malignant B-cell lymphoma was determined by immunohistochemistry. General screening revealed no further manifestations of the lymphoma. THERAPY AND OUTCOME: The patient initially refused any therapy until a painful secondary neovascular glaucoma with complete loss of visual function developed, thus prompting us to perform an enucleation. The following immunohistochemical examination confirmed the initial diagnosis. A chemotherapy with high-dose methotrexate and leucovorin rescue was initiated. CONCLUSIONS: Primary intraocular lymphoma can present as diffuse uveitis refractory to corticosteroids. Diagnosis can be difficult and is often delayed.

Night blindness in Sorsby's fundus dystrophy reversed by vitamin A.

Sorsby's fundus dystrophy (SFD) is an autosomal dominant retinal degeneration caused by mutations in the tissue inhibitor of metalloproteinases-3 (TIMP3) gene. Mechanisms of the visual loss in SFD, however, remain unknown. In a SFD family with a novel TIMP3 point mutation, we tested a hypothesis that their night blindness is due to a chronic deprivation of vitamin A at the level of the photoreceptors caused by a thickened membrane barrier between the photoreceptor layer and its blood supply. Vitamin A at 50,000 IU/d was administered orally. Within a week, the night blindness disappeared in patients at early stages of disease. Nutritional night blindness is thus part of the pathophysiology of this genetic disease and vitamin A supplementation can lead to dramatic restoration of photoreceptor function.